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SDG 6

The Ecological Reserve: Towards a common understanding for river management in South Africa
17 April 2007
Stellenbosch University

van Wyk, E;Breen, CM;Roux, DJ;Rogers, KH;Sherwill, T;van Wilgen, BW

The legal requirement for an Ecological Reserve established in South Africa's water law is commonly regarded by stakeholders as being in direct competition with the needs of humans. This has resulted in much debate and varying interpretations of the meaning and purpose of the Ecological Reserve. However, the requirement for water that is allocated to sustain ecosystem functions is directly aligned with options for human use arising from rivers to deliver a suite of ecosystem goods and services to society. In this paper, we propose a conceptual approach to support a more constructive debate around the role and function of the Reserve in the sustainable use and protection of a suite of benefits to society. The approach proposes that debate be structured around managing for a dynamic ecological state in rivers that would in turn achieve the desired (albeit dynamic) mix of goods and services to a wide range of stakeholders. These stakeholders come from widely differing socioeconomic backgrounds, and their needs may be either for the direct use of water and associated resources located within the macro channels of rivers, or for their use in supporting social and economic activity remote from the river. The paper shows how goods and services concepts can provide an approach that contributes to developing a shared understanding that facilitates decisions on water allocations. The implication is that when water allocations can be evaluated comparatively it creates greater awareness of each other's needs and interdependencies and value is attached to a greater diversity of benefits and costs. This in turn allows for opportunities to achieve more equitable recognition and allocation of the resources associated with rivers. The approach assists in making the conceptual link between goods and services that arise from constructed production systems, and those that arise from natural production systems (i.e. ecosystems). Off-site as well as on-site use of river goods and services (the latter being catered for by the Ecological Reserve) can in this way be brought into debate in a way that promotes wider appreciation of society's diverse uses of river resources. In doing so it promotes interest-based participation as intended by legislation.
Gas exchange characteristics, metabolic rate and water loss of the Heelwalker, Karoophasma biedouwensis (Mantophasmatodea : Austrophasmatidae)
19 April 2007
Stellenbosch University

Chown, SL;Marais, E;Picker, MD;Terblanche, JS

This study presents the first physiological information for a member of the wingless Mantophasmatodea, or Heelwalkers. This species shows cyclic gas exchange with no evidence of a Flutter period (more typical of discontinuous gas exchange in insects) and no indication that the spiracles are fully occluded during quiescent metabolism. Standard metabolic rate at 20 degrees C was 21.32 +/- 2.73 mu l CO2 h(-1) (mean +/- S.E.), with a Q(10) (10-25 degrees C) of 1.7. Increases in (VCO2)-C-center dot associated with variation in mass and with trial temperature were modulated by an increase in burst period volume and a decline in cycle frequency. Total water loss rate, determined by infrared gas analysis, was 0.876 +/- 0.08 mg H2O h(-1) (range 0.602-1.577, n = 11) whilst cuticular water loss rate, estimated by linear regression of total water loss rate and metabolic rate, was 0.618 +/- 0.09 mg H2O h(-1) (range 0.341-1.363, n = 11). Respiratory water loss rate was therefore no more than 29% of the total rate of water loss. Both total water loss rate and estimated cuticular water loss rate were significantly repeatable, with intraclass correlation coefficients of 0.745 and 0.553, respectively. (c) D 2006 Elsevier Ltd. All rights reserved.
Perspective: The challenge of ecologically sustainable water management
25 April 2007
Stellenbosch University

Bernhardt, E.;Bunn, S.E.;Hart, D.D.;Malmqvist, B.;Timo-Muotka, T.;Naiman, R.J.;Pringle, C.;Martin Reuss, M.;van Wilgen, B.W.

Sustainable water resource management is constrained by three pervasive myths; that societal and environmental water demands always compete with one another; that technological solutions can solve all water resource management problems; and that environmental solutions to protect and maintain freshwater resources are more expensive and less dependable than technological solutions. We argue that conservation and good stewardship of water resources can go a long way toward meeting societal demands and values. Furthermore, water requirements to sustain ecosystem health and biodiversity in rivers and their associated coastal systems can be well aligned with options for human use and deliver a suite of ecosystem goods and services to society. However, to achieve ecologically sustainable water management, we propose several key issues that must be addressed. The objective of this opinion paper is to stimulate discussion across traditional discipline boundaries with the aim of forging new partnerships and collaborations to meet this pressing challenge of ecologically sustainable water management.
Riparian scrub recovery after clearing of invasive alien trees in headwater streams of the Western Cape, South Africa
25 April 2007
Stellenbosch University

Galatowitsch, S;Richardson, DM

Headwater rivers are the predominant kind of aquatic ecosystem in South Africa's Cape Floristic Region. Invasion by alien woody taxa (especially Acacia longifolia and Acacia mearnsii) have altered these rivers in recent decades, replacing indigenous vegetation and altering ecosystem functioning. Aliens have been systematically cleared in watercourses since 1995 as part of a national program ("Working for Water") to increase water production and improve water quality. Cleared sites are mostly left to recover to their pre-invasion state without additional intervention. We compared the vegetation of seven rivers that vary in their extent of invasion and clearing to identify factors limiting recolonization. Dense invasions cleared 3-6 years before the survey differ in vegetation structure and composition from uninvaded or lightly invaded/cleared riparian reaches in the following ways: (1) diminished extent of indigenous trees in the canopy and increased importance of shrubs or reinvading alien trees, (2) reduced species richness, (3) reduced likelihood of occupancy for more than one-third of common, indigenous species, and (4) reduced incidence of indigenous tree regeneration. Overall, indigenous tree regeneration is very low and not disturbance-triggered which will likely result in slow recovery without additional intervention. We recommend focusing active revegetation on common riparian scrub trees (i.e., Metrosideros angustifolia, Brachylaena neriifolia, Brabejum stellatfolium, and Erica caffra). These species tolerate open habitats favored by alien trees, eventually forming closed canopies required by shade-tolerant species. Accelerating establishment of these small trees is likely critical for shifting cleared riparian corridors from a state that favors alien reinvasion. Effective establishment strategies will need to be developed in the context of hydrologic impairment, since alien-invaded rivers in this region typically have reduced flow. (C) 2004 Elsevier Ltd. All rights reserved.
Invasive alien plants and South African rivers: a proposed approach to the prioritization of control operations
25 May 2007
Stellenbosch University

van Wilgen, BW;Nel, JL;Rouget, M

1. A number of parallel initiatives in South Africa have been addressing the prioritization and management of invasive alien plant species, the prioritization of rivers for the conservation of biodiversity, and broad-scale planning for water resource management. This paper has combined aspects of these approaches to develop a composite index of prioritization of quaternary catchments for alien plant control purposes. 2. We calculated, for each quaternary catchment, a simple composite index that combined estimates of (i) the number of invasive alien plant species present; (ii) the potential number of invasive alien plant species that would be present if they occupied the full range as determined by climatic envelope models; (iii) the degree of habitat loss in rivers; and (iv) the degree of water stress. Each of the four components contributed between one and four to the combined index, which had a range of values between four and 16. 3. We used a geographic information system to map the distribution of priority catchments for invasive alien plant control. Of the 1911 quaternary catchments in South Africa and Lesotho, just over one-third (650) were in the highest priority category with an index of 13 or more. A relatively small proportion (273, or 14%) of the catchments had the maximum scores of 15 or 16. 4. The approach identified priority areas that have not currently been identified as such, and should provide decision makers with an objective and transparent method with which to prioritize areas for the control of invasive alien plants. We anticipate debate about the way in which components of the index are calculated, and the weight given to the different components, and that this will lead to the transparent evolution of the index. Improvements would also come about through the addition of a more comprehensive list of species, and through the addition of further components.
Stakeholder connectedness and participatory water resource management in South Africa
25 October 2010
Stellenbosch University

Sherwill, T.;Arendse, L.;Rogers, K.;Sihlophe, N.;van Wilgen, B.W.;van Wyk, E.;Zeka, S.

Establishment of catchment management agencies (CMAs) is central to South Africa’s new policy vision for achieving decentralised, participatory integrated water resource management. However, CMAs cannot directly engage every individual stakeholder – inputs will need to be channelled via a hierarchical representation system. The issue of ‘connectedness’ is crucial: how do interest groupings interact across and between scales? Research in the Inkomati catchment suggests that current levels of organisation, communication and capacity could result in inequitable, unsustainable participatory decisions. Large imbalances in degree of organisation and negotiating power exist between different sectors and regions. Though some cooperative initiatives exist, there appears to be a greater focus on engaging government or legal processes, contrary to the intentions of the new water policy. Suggested interventions include: capacity building for disadvantaged groups; facilitation of catchment-based fora as vehicles for co-learning and relationship-building; and educating all stakeholders about the new water policy. All must create awareness of benefits of engaging other stakeholders and the future CMA, and thus an imperative for resource users to align themselves towards this goal.
Bias, precision and accuracy in the estimation of cuticular and respiratory water loss: A case study from a highly variablecockroach, Perisphaeria sp.
27 October 2010
Stellenbosch University

Gray, E.M.;Chown, S.L.

We compared the precision, bias and accuracy of two techniques that were recently proposed to estimate the contributions of cuticular and respiratory water loss to total water loss in insects. We performed measurements of VCO2 and VH2O in normoxia, hyperoxia and anoxia using flow through respirometry on single individuals of the highly variable cockroach Perisphaeria sp. to compare estimates of cuticular and respiratory water loss (CWL and RWL) obtained by the VH2O–VCO2 y-intercept method with those obtained by the hyperoxic switch method. Precision was determined by assessing the repeatability of values obtained whereas bias was assessed by comparing the methods’ results to each other and to values for other species found in the literature. We found that CWL was highly repeatable by both methods (R≥0.88) and resulted in similar values to measures of CWL determined during the closed-phase of discontinuous gas exchange (DGE). Repeatability of RWL was much lower (R = 0.40) and significant only in the case of the hyperoxic method. RWL derived from the hyperoxic method is higher (by 0.044 μmol min-1) than that obtained from the method traditionally used for measuring water loss during the closed-phase of DGE, suggesting that in the past RWL may have been underestimated. The very low cuticular permeability of this species (3.88 μg cm-2 h-1 Torr-1) is reasonable given the seasonally hot and dry habitat where it lives. We also tested the hygric hypothesis proposed to account for the evolution of discontinuous gas exchange cycles and found no effect of respiratory pattern on RWL, although the ratio of mean VH2O to VCO2 was higher for continuous patterns compared with discontinuous ones.
Impact of a dam on benthic macroinvertebrates in a small river in a biodiversity hotspot: Cape Floristic Region, South Africa
08 November 2010
Stellenbosch University

Bredenhand, E.;Samways, M.J.

Suitable reservoirs and monitoring methods are needed to manage scarce water supplies in dry countries. We assessed here the impact on aquatic macroinvertebrates of the only dam on the Eerste River, which runs through the heart of a biodiversity hotspot, the Cape Floristic Region, South Africa. The dam and associated activities, were the only forms of disturbance in this otherwise pristine area. We sampled over 20,000 macroinvertebrate individuals and illustrated some categorical effects of the impoundment and its effects on macroinvertebrate assemblages. Macroinvertebrate species diversity below the dam was only half of that in the pristine catchment area above the dam. Furthermore, Ephemeroptera, Plecoptera and Trichoptera diversity and abundance dropped to almost zero as a result of the impoundment. In contrast, the abundance of the Diptera family Chironomidae increased substantially below the dam. These changes in macroinvertebrate diversity mirrored those recorded in biologically less diverse areas, but are of major concern in this biodiversity hotspot with its rich endemic fauna. We conclude that such an impoundment, while important for human welfare, results in a high price being paid in terms of loss of local biodiversity.
Conserving the fishes of the Twee River, Western Cape, South Africa: revisiting the issues
15 November 2010
Stellenbosch University

Marr, S.M.;Sutcliffe, L.M.E.;Day, J.A.;Griffiths, C.L.;Skelton, P.H.

The Twee River catchment contains two endemic fish species — the Twee River redfin and the Twee River galaxias — which are threatened by water abstraction, habitat degradation, and the presence of introduced fishes. Fyke nets were used to determine the current distribution ranges of fish in the catchment to update a 1997 survey and to provide key information for the compilation of a conservation strategy for the Twee River redfin, Barbus erubescens. Population estimates from 1997 placed their total number at 8 400, but population size could not be estimated from the present surveys. A number of small populations of Twee River redfin and Twee River galaxias, which are restricted to two short stretches of tributary rivers, were identified. Their long-term survival remains uncertain. Conservation action, including the eradication of alien fish and the creation of a dedicated sanctuary for the endemic populations, is recommended.
Water stress tolerance of shrubs in Mediterranean-type climate regions: convergence of fynbos and succulent Karoo communities with California shrub communities
22 November 2010
Stellenbosch University

Jacobsen, A.L.;Esler, K.J.;Pratt, R.B.;Ewers, F.W.

Mediterranean-type climate regions are highly biodiverse and predicted to be particularly sensitive to climate change. Shrubs of the mediterranean-type climate region of South Africa are highly threatened, and their response to water stress has been comparatively little studied. Resistance to water stress induced xylem cavitation (P50) and xylem specifi c hydraulic conductivity (Ks) were measured in 15 shrub species from fynbos and succulent karoo communities of South Africa. Species displayed a fivefold variation in cavitation resistance (P50 of −1.9 to −10.3 MPa) with succulent karoo species displaying greater interspecific variability in P50 than fynbos species. Principal components analysis (including P50, minimum seasonal water potential, Ks, and xylem density) showed the response to water stress in fynbos species to be similar to chaparral species from the mediterranean-type climate region of California. The data suggest convergence of community and species-specific water stress “strategies” between these mediterranean-type climate regions with respect to their xylem traits. On the basis of the current study and reported plant death and dieback in these regions, woody species within the fynbos may be more susceptible to climate warming and drying than those within the succulent karoo that appear to be utilizing more diverse xylem strategies in response to water stress.
Effects of thermal acclimation on water loss rate and tolerance in the collembolan Pogonognathellus flavescens
23 November 2010
Stellenbosch University

Leinaas, H.P.;Slabber, S.;Chown, S.L.

A few days of thermal acclimation (to 5°C versus 15°C) may strongly affect tolerance to drought stress in Collembola. To better understand this phenomenon, the effect of acclimation on water loss rate and its consequence for survival in the species Pogonognathellus flavescens Tullberg (Tomoceridae) is investigated. Acclimation does not affect the water content of hydrated animals but animals exposed to 15°C and 76% relative humidity lose water much faster after having been acclimated to 5°C rather than 15°C. Tolerance to water loss is not affected; in both treatment groups, animals survive up to 40% loss of the water content recorded when fully hydrated. The percentage water content of hydrated animals decreases with size, which may explain why the proportion of initial water lost appears to be a better predictor for survival than the amount of remaining water. The proportion of initial water lost per unit time is little influenced by size in animals acclimated to 15°C but increases with decreasing size in the group at 5°C, indicating that acclimation affects a physiological protection against water loss.
Recovery of benthic macroinvertebrate and adult dragonfly assemblages in response to large scale removal of riparian invasive alien trees
27 May 2011
Stellenbosch University

Magoba, R.N.;Samways, M.J.

Invasive alien organisms can impact adversely on indigenous biodiversity, while riparian invasive alien trees (IATs), through shading of the habitat, can be a key threat to stream invertebrates. We ask here whether stream fauna can recover when the key threat of riparian IATs is removed. Specifically, we address whether IAT invasion, and subsequent IAT removal, changes benthic macroinvertebrate and adult dragonfly assemblages, for the worse or for the better respectively. Natural riparian zones were controls. There were statistically significant differences between stream reaches with natural, IAT-infested and IAT-cleared riparian vegetation types, based on several metrics: immature macroinvertebrate taxon richness, average score per macroinvertebrate taxon (ASPT), a macroinvertebrate subset (Ephemeroptera, Plecoptera, Trichoptera and Odonata larvae; EPTO), and adult dragonfly species richness. Reaches with natural vegetation, or cleared of IATs, supported greater relative diversity of macroinvertebrates than reaches shaded by dense IATs. Greatest macroinvertebrate ASPT and EPTO were in reaches bordered by natural vegetation and those bordered by vegetation cleared of IATs, and the lowest where the riparian corridor was IATs. Highest number of adult dragonflies species was along streams cleared of dense IATs. Overall, results showed that removal of a highly invasive, dense canopy of alien trees enables recovery of aquatic biodiversity. As benthic macroinvertebrate scores and adult dragonfly species richness are correlated and additive, their combined use is recommended for river condition assessments.
Effect of alien riparian vegetation and its removal on a highly endemic river macroinvertebrate community
12 December 2011
Stellenbosch University

Samways, M.J.;Sharratt, N.J.;Samaika, J.P.

Invasive alien trees along river banks can reduce indigenous biodiversity, while their removal can restore it. We assessed here family- and specieslevel responses of river benthic macroinvertebrate assemblages to three riparian vegetation types (natural, alien trees, cleared of alien trees) in the Cape Floristic Region biodiversity hotspot. High species beta diversity of this highly endemic fauna meant that between-river, as well as seasonal effects, dominated assemblage patterns. SASS5, a qualitative, rapid bioassessment technique, based on the sensitivity of the families present, was used as a measure of river health and, indirectly, of water quality. SASS indicated a decline in water quality conditions after alien clearing, a likely response to the greater insolation and apparent erosion of cleared banks, resulting in elevated temperatures and suspended solids and lowered oxygen levels. Overall, cleared and natural sites were more similar to each other than to alien sites, suggesting some post-clearing recovery. However, many sensitive, endemic taxa survived in alien invaded sites, and more than in the natural sites. These endemic species made use of shady, cool, highoxygen levels under the alien tree canopy. However, endemics declined in overall abundance in sites cleared of aliens, being replaced by more tolerant, widespread taxa. Clearance of the alien trees opened up the rivers to sunny conditions, which had a major impact on community composition. Vegetation types, oxygen levels and river width were important environmental variables affecting these macroinvertebrate responses. Re-establishment of invertebrate biodiversity matched that of indigenous vegetation, with the most sensitive endemic taxa only recovering after establishment of bushy indigenous and shadeproducing fynbos. Therefore, for biodiversity conservation objectives to be achieved, it is essential that indigenous plants are maintained and encouraged during and after clearing to ensure the recovery of endemic and sensitive taxa.
RS & GIS-based Spatialtemporal Analysis of Ecological Footprint and Biocapacity Pattern of Jinghe River Watershed in China: Does Supply Meet Demand?
23 January 2012
Stellenbosch University

Yue, Dongxia;Ma, Jinhui;Guo, Jianjun;Zhang, Jiajing;Du, Jun;Song, Yajie;Hui, Cang

The Ecological Footprint methodology is a framework that tracks Ecological Footprint (humanity’s demands on the biosphere) by comparing human demand against the regenerative capacity (Biocapacity) of the planet (WWF, 2010) to advance the science of sustainability. As such, the spatiotemporal dynamics of the Ecological Footprint (EF) and Biocapacity (BC) in a given watershed are important topics in the field of sustainability research based on remote sensing (RS) data and geographic information system (GIS) techniques．This paper reports on a case study of the Jinghe River Watershed using improved EF methodology with the help of GIS and high resolution remote sensing data, to quantitatively estimate the relationship between EF demand and BC supply and analyze their spatial distribution patterns at multiple spatial scales for four periods (1986, 1995, 2000 and 2008). We predict the future BC both overall, and of six categories of biological productivity area for the next four decades using the Markov Chain Method．The results showed that the spatial distribution of EF demand and BC supply were significantly uneven in the region, in which the per-capita EF of all counties located in the watershed increased continually from 1986 to 2008, and the EF per person of counties in the middle and lower reaches area was markedly greater than that in the upper reaches over time. On the supply side, the per-capita BC of all counties decreased gradually from 1986 to 2008, and the per-capita BC of counties in the upper reaches area was greater than that in the middle and lower reaches during the period, causing the uneven spatial distribution of Ecological budget-the gap between supply and demand, showed that the Jinghe River Watershed on the whole has begun to be unsustainable since 2008, with each county exhibiting differential temporal patterns. The prediction results showed that the total BC will increase continually from 2020 to 2050, and the BC of six categories will reduce, indicating that unsustainability in the region will escalate. As a whole, The EF demand has exceeded the BC supply, and the gap was widening in the Jinghe Watershed. This paper provided an in-depth portrait of the spatiotemporal dynamics of EF and BC, as well as their interactions with humanity and ecosystems.
Impacts of invasive alien plants on water quality, with particular emphasis on South Africa
19 February 2013
Stellenbosch University

Chamier, J.;Schachtschneider, K.;Le Maitre, D.C.;Ashton, P.J.;van Wilgen, B.W.

We review the current state of knowledge of quantified impacts of invasive alien plants on water quality, with a focus on South Africa. In South Africa, over 200 introduced plant species are regarded as invasive. Many of these species are particularly prominent in riparian ecosystems and their spread results in native species loss, increased biomass and fire intensity and consequent erosion, as well as decreased river flows. Research on the impact of invasive alien plants on water resources has historically focused on water quantity. However, although invasive alien plants also affect the quality of water, this aspect has not been well documented. Alien invasive plants increase evaporation rates, and reduce stream flow and dilution capacity. The biomass inputs of alien invasive plants, especially nitrogen fixers such as Acacia spp., alter nutrient cycles and can elevate nutrient concentrations in groundwater. Alien plant invasions alter the fire regimes in invaded areas by changing the size, distribution and plant chemistry of the biomass. More intense fires increase soil erosion and thereby decrease water quality. In contrast to riparian invasions, aquatic invasive plants have been more extensively studied in South Africa and their impacts on water quality have been relatively well monitored. Water quality in South Africa is rapidly deteriorating, and all factors that influence this deterioration need to be taken into account when formulating actions to address the problem. The changes in water quality brought about by alien plant invasions can exacerbate the already serious water quality problems.
The prioritisation of invasive alien plant control projects using a multi-criteria decision model informed by stakeholder input and spatial data
22 February 2013
Stellenbosch University

Forsyth, G.G.;Le Maitre, D.C.;O'Farrell, P.J.;van Wilgen, B.W.

Invasions by alien plants are a significant threat to the biodiversity and functioning of ecosystems and the services they provide. The South African Working for Water program was established to address this problem. It needs to formulate objective and transparent priorities for clearing in the face of multiple and sometimes conflicting demands. This study used the analytic hierarchy process (a multi-criteria decision support technique) to develop and rank criteria for prioritising alien plant control operations in the Western Cape, South Africa. Stakeholder workshops were held to identify a goal and criteria and to conduct pair-wise comparisons to weight the criteria with respect to invasive alien plant control. The combination of stakeholder input (to develop decision models) with data-driven model solutions enabled us to include many alternatives (water catchments), that would otherwise not have been feasible. The most important criteria included the capacity to maintain gains made through control operations, the potential to enhance water resources and conserve biodiversity, and threats from priority invasive alien plant species. We selected spatial datasets and used them to generate weights that could be used to objectively compare alternatives with respect to agreed criteria. The analysis showed that there are many high priority catchments which are not receiving any funding and low priority catchments which are receiving substantial allocations. Clearly, there is a need for realigning priorities, including directing sufficient funds to the highest priority catchments to provide effective control. This approach provided a tractable, consensus-based solution that can be used to direct clearing operations.
Beneficiaries’ aspirations to permanent employment within the South African Working for Water Programme
26 February 2013
Stellenbosch University

Hough, J.A.;Prozesky, H.

The South African Working for Water (WfW) programme is a short-term public works programme (PWP) focused on clearing invasive alien plants, while training and empowering the marginalised poor to find employment. Furthermore, it aims to develop independent, entrepreneurial contractors who should ‘exit’ from the programme into the broader labour market. However, evidence indicates that many beneficiaries have become financially dependent on this employment, and find it difficult to search for alternatives. Understanding the reasons for this dependence from the perspective of the beneficiaries of this PWP is crucial to align such projects to the actual needs of the beneficiaries, but these have not yet been considered from a sociological perspective. This article reports on data collected, through face-to-face interviews, on WfW beneficiaries’ aspirations to permanent employment in four projects in the Winelands and Overberg districts of the Western Cape. It presents the novel finding that the social structures within projects themselves seem to create a need to remain in the WfW programme. In addition, a misalignment between these projects’ implementation and beneficiaries’ aspirations to financial stability (associated with permanent employment in WfW) is highlighted. The authors argue that WfW should respond to these aspirations, rather than pursue the ostensibly unrealistic aim of creating independent entrepreneurs. Finally, the implications of these findings for PWPs globally, and their concerns regarding the inadvertent creation of beneficiary dependence, are outlined.
Evaluating the cost-effectiveness of invasive alien plant control: A case study from South Africa
27 February 2013
Stellenbosch University

McConnachie, M.;Cowling, R.M.;van Wilgen, B.W.

Conservation projects spend billions of dollars clearing invasive alien plants, yet few studies have measured the cost-effectiveness of doing this, especially over larger spatial and temporal scales, relevant to operational contexts. We evaluated the cost-effectiveness of South Africa’s national invasive alien plant control programme, Working for Water, in reducing invasive alien plant cover in the Krom and Kouga river catchments over 7 years. We assessed change in invasive alien plant cover by comparing post-treatment cover with the first recorded pre-treatment cover across all 740 of the two project’s treatment sites (ranging from 0.03 to 227.6 ha in size). We also used regression analysis to estimate the effect of predictor variables on the cost-effectiveness of invasive alien plant clearing. We found – by dividing the total costs by the change in invasive alien plant cover – that it cost 2.4 times more (1.5 times for the Krom, and 8.6 times for the Kouga project) to clear invaded land than the highest equivalent estimate made elsewhere. At current rates of clearing, it would take 54 and 695 years to clear the catchments, in the Krom and Kouga, respectively, assuming no further spread. If spread is considered, current control efforts are inadequate, and invasions are likely to continue to spread in the catchments. Pre-treatment invasive alien plant cover and treatment costs per hectare had the greatest positive and negative influence, respectively on cost-effectiveness. Our assessment suggests that invasive alien plant control projects urgently need to monitor their cost-effectiveness so that management practices can be adapted to use scarce conservation funds more effectively.
An assessment of a proposal to eradicate non-native fish from priority rivers in the Cape Floristic Region, South Africa
27 February 2013
Stellenbosch University

Marr, S.M.;Impson, N.D.;Tweddle, D.

Non-native fish are considered the most important threat to the survival of the indigenous freshwater fishes in the Cape Floristic Region (CFR). A pilot project to evaluate the use of the piscicide rotenone to eradicate non-native fish from selected reaches in four rivers has been proposed by CapeNature, the conservation authority of the Western Cape province, South Africa. Each river has unique characteristics and challenges to achieving the eradication of non-native fish and the restoration of its indigenous fish assemblage. The proposal is described and the management methods available for reducing the impact of non-native fish on indigenous species are discussed. An environmental impact assessment (EIA) concluded that the project was justified and necessary, the choice of rivers sound, and supported the use of piscicides. The need for the project, the selection of sites and the findings of the EIA are discussed. It is expected that the project will be successful while having minimal impact on other aquatic fauna. The successful completion of the pilot project could help establish methods to eradicate non-native fish from critical biodiversity areas in South Africa. Such projects must, however, be part of a comprehensive conservation management plan to be implemented by conservation agencies in the CFR.
Ecological niche modeling of the invasive potential of Nile tilapia Oreochromis niloticus in African river systems: concerns and implications for the conservation of indigenous congenerics
30 June 2013
Stellenbosch University

Zengeya, T.A.;Robertson, M.P.;Booth, A.J.;Chimimba, C.T.

This study applied ecological niche models to determine the potential invasive range of Nile tilapia, Oreochromis niloticus, with a particular focus on river systems in southern Africa where it is now established and spreading. Computational tools such as niche models are useful in predicting the potential range of invasive species, but there are limitations to their application. In particular, models trained on native records may fail to predict the full extent of an invasion. This failure is often attributed to changes in either the niche of the invading species or the variables used to develop the models. In this study, we therefore evaluated the differences in the predictive power of models trained with different environmental variables, the effect of species range (native vs. introduced) on model performance and assessed whether or not there is evidence suggestive of a niche shift in Nile tilapia following its introduction. Niche models were constructed using Maxent and the degree of niche similarity was assessed using Schoener‘s index. Null models were used to test for significance. Model performance and niche conservatism varied significantly with variable selection and species range. This indicates that the environmental conditions available to Nile tilapia in its native and introduced ranges are not congruent. Nile tilapia exhibited broad invasive potential over most of southern Africa that overlaps the natural range of endemic congenerics. Of particular concern are areas which are free of exotic species but are now vulnerable due to the promotion of fish introductions mainly for aquaculture and sport fishing.
The challenges of alleviating poverty through ecological restoration: Insights from South Africa's "Working for Water" program
11 June 2014
Stellenbosch University

McConnachie, M.M.;Cowling, R.M.;Shackleton, C.M.;Knight, A.T.

Public works programs have been posited as win–win solutions for achieving societal goals for ecological restoration and poverty alleviation. However, little is documented regarding the challenges of implementing such projects. A commonly cited example is South Africa’s invasive alien plant control program “Working for Water” (WfW), which aims to create employment via restoring landscapes invaded with alien plants. Recent studies have raised questions over the effectiveness of this program in achieving both its restoration and poverty alleviation goals. This is the first study that we are aware of that synthesizes the knowledge of managers on both the poverty alleviation and environmental outcomes of a public works project. Herein, we sought to understand the challenges and constraints faced by 23 WfW managers in fulfilling the program’s environmental and poverty alleviation objectives. We found that the challenges most frequently cited by managers related to the capacity and competence of managers and teams, followed by challenges relating to planning and coordination, specifically the challenges of being flexible and adaptive when constrained by operating procedures. In addition, the current focus on maximizing short-term employment was perceived by some as limiting the efficiency and long-term effectiveness of the WfW program in achieving its environmental and social goals. We suggest that improving the conditions and duration of employment could improve the effectiveness of invasive alien plant control and ecological outcomes. We also suggest that WfW measure the impacts of their interventions through an adaptive management approach so that it can learn and adapt to the challenges it faces.
Casuarina cunninghamiana in the Western Cape, South Africa: Determinants of naturalisation and invasion, and options from management
30 July 2014
Stellenbosch University

Potgieter, L.J.;Richardson, D.M.;Wilson, J.R.U.

Alien species that are desirable and commercially important in some parts of the landscape but damaging invaders in other parts present a special challenge for managers, planners, and policy-makers. Casuarina cunninghamiana (Casuarinaceae), native to the eastern and north-eastern coasts of Australia, has been cultivated in South Africa for more than a century. This study explores the invasion ecology of C. cunninghamiana in the south-western part of the Western Cape. We examined differences between naturalized and non-naturalized populations (e.g. the roles of propagule pressure, land use and bioclimatic suitability), assessed invasion risk, and provide recommendations for control. Naturalisation was observed in 81% of the populations surveyed. In climatically suitable areas, propagule pressure and distance to water bodies and water courses were significant predictors of naturalisation — naturalisation was most likely to occur within 100 m from the nearest planted individual and close to water bodies and water courses. The species has also naturalized in regions with suboptimal bioclimatic conditions, but then only very close (b10 m) to planted trees. Based on our findings we recommend: 1) the immediate removal of female trees from within 100 m of water bodies and water courses; 2) all future sales and plantings to be restricted to male plants; and 3) the development of a management strategy (potentially including biological control) to control existing invasions and limit future spread. If these steps are taken, we believe it would be possible to maintain the beneficial uses the species has in some locations without incurring substantial negative impacts in other locations.
Reflections on the history of aquatic science in South Africa with particular reference to the period after 1994
24 March 2015
Stellenbosch University

Roux, D.J.;Breen, C.M.;Carruthers, J.

In this article we reflect on how freshwater research has evolved in South Africa from its beginnings in the early 20th century and how it has altered over time to align with the post-1994 socio-political environment. We situate aquatic science within a research question to explore why aquatic science has developed in the manner it has done, providing some of the broader environment of political change, access to funding, the relevance of particular research themes at different times, and the research agenda of some prominent individual scientists. We do not, therefore, intend merely to itemise what has been achieved over the years. Our intention is to develop an historical context that may help frame research in ways that bridge the cultural divides that persist between the humanities and the sciences. Moreover, although water is crucial to life and livelihoods in a country of scarce water resources, the fields of aquatic study are not generally familiar to the South African public and do not have the high profile they merit. In order to chart important current developments in freshwater research, this article highlights significant aspects of this scientific arena during the earlier part of the 20th century that are pertinent to explaining how and why the current situation, by way of research fields, policy and legislation came into being. The history has been necessitated by, and driven by, regional socio-economic and geopolitical factors as well as developments in the relevant scientific disciplines. After examining how this state of affairs came to be, an overview of the present state of the field is provided.
Value of artificial ponds for aquatic beetle and bug conservation in the Cape Floristic Region biodiversity hotspot
14 April 2015
Stellenbosch University

Apinda Legnouo, E.A.;Samways, M.J.;Simaika, J.P.

1. Freshwater insect species and their host ecosystems are widely threatened. This is particularly so within the agricultural and urban landscapes of Mediterranean-type ecosystems, including those of the Cape Floristic Region (CFR), South Africa. The value of 18 artificial ponds in the CFR was determined for aquatic beetle and bug abundance and species richness, a topic that has been little explored in Africa in general. 2. In total, 17 814 aquatic beetle and bug individuals were sampled, from 94 taxa, representing 37 genera and 57 species. Bugs were much more abundant than beetles, representing 82% of all the individuals collected. The beetle and bug fauna showed high levels of endemism, with 36% restricted to the Western Cape Province. 3. Five distinct groupings based on species abundances were identified, revealing overall high dissimilarities between groups, ranging from 65% to 82%. 4. The associated physico-chemical characteristics of these sites were also investigated. The most important characteristics structuring pond communities were elevation, temperature, pH, pond size and flow regime. For bugs alone, the same variables, except elevation, were important. For beetles, only three variables were found to be most important in explaining community structure: elevation, pH, and flow regime. 5. Artificial ponds in the CFR increase the area of occupancy of these insects, and therefore play a major role in conserving them.
Non-native rainbow trout change the structure of benthic communities in headwater streams of the Cape Floristic Region, South Africa
29 June 2015
Stellenbosch University

Shelton, J.M.;Samways, M.J.;Day, J.A.

Introduced rainbow trout Oncorhynchus mykiss have invaded many headwater streams in the Cape Floristic Region (CFR) and depleted, or eliminated, native fish populations. However, the question of whether trout invasions also have consequences for lower trophic levels in these systems has not been addressed. We used a broad-scale comparative study in the upper Breede River catchment (CFR) to evaluate differences in benthic community structure between sites on headwater streams with and without trout, and thereby infer community-level impacts of trout. There were differences in invertebrate abundance and assemblage composition, and algal biomass, between sites with and without trout. Specifically, the abundance of certain herbivorous invertebrate taxa was higher, and the biomass of benthic algae lower, at sites invaded by trout. This pattern implies that trout have induced a trophic cascade by releasing herbivorous invertebrates from predation, leading to an increase in grazing pressure and a consequent indirect decrease in the biomass of benthic algae; a pattern that contrasts with the majority of studies investigating community-level impacts of introduced trout elsewhere. These findings, together with comparisons of environmental conditions between invaded and uninvaded sites, indicate that trout invasions have changed the structure and function of benthic communities in these streams.
Predatory impact of non-native rainbow trout on endemic fish populations in headwater streams in the Cape Floristic Regian of South Africa
29 June 2015
Stellenbosch University

Shelton, J.M.;Samways, M.J.;Day, J.A.

Non-native rainbow trout Oncorhynchus mykiss have been widely introduced in the Cape Floristic Region (CFR) at the south-western tip of Africa and may pose a serious threat to endemic freshwater fishes in the region. Quantitative information about trout impacts in the CFR is scarce but is urgently needed to guide legislation and management efforts. We used a combination of comparative and experimental approaches to evaluate impacts of introduced trout on native fish populations in headwater streams draining the upper Breede River catchment in the CFR. Fish populations were surveyed, and 19 environmental variables measured, in 24 minimally disturbed streams, half of which had been invaded by trout. The mean densities of native Breede River redfin Pseudobarbus burchelli, Cape kurper Sandelia capensis and Cape galaxias Galaxias zebratus, were 89–97 % lower in invaded streams than in streams without trout. Furthermore, while native fish were present at all 12 sites without trout, they were not recorded at seven of the 12 invaded sites. None of the measured environmental variables differed significantly between sites with and without trout, and distance-based linear models identified trout density as the best predictor of redfin and kurper density, while galaxias density was best predicted by other environmental variables (riparian vegetation, canopy cover, substrate length, site slope). Native fish B40 mm in length were largely absent from invaded streams, but generally abundant in streams without trout, and a field experiment confirmed that trout selectively consume small redfin. Taken together, these findings constitute evidence that trout have depleted the abundance of CFR-endemic fishes through size-selective predation. It is recommended that managers aim to prevent new trout introductions and consider eradicating trout populations where they pose a threat to highly threatened native species.
What drives the use of scientific evidence in decision making? The case of the South African Working for Water program
14 August 2015
Stellenbosch University

Ntshotsho, P.;Prozesky, H.E.;Esler, K.J.;Reyers, B.

Academic scientific literature abounds with critique of natural resource managers for not utilising scientific evidence when making decisions in their day-to-day operations. Little regard is given by the critics to the practical constraints on the use of research findings, as experienced by managers in their work environments. To explore these issues, we conducted a case study of the Working for Water (WfW) program, a government-funded invasive alien plant (IAP) management program that has been operational in South Africa for nearly two decades. We investigated the extent to which decision makers in WfW use scientific evidence to inform their decisions pertaining to the clearing of IAPs and also identified opportunities for, and constraints to, evidence-based practice. Our results indicate that the use of scientific evidence is limited by the fact that the management of natural resources involves much more than science. The social context within which decisions are made, which includes organizational structure, priorities and capacity, plays an important part in the extent to which science informs practice. On the basis of our findings, we highlight the importance of generating evidence in practice through an iterative process of implementation, monitoring, learning and reflection, and subsequent feedback into the planning of restoration projects.
Links between lateral vegetation zones and river flow
02 September 2015
Stellenbosch University

Reinecke, M.K.;Brown, C.A.;Esler, K.J.;King, J.M.;Kleynhans, M.T.;Kidd, M.

Plant species are known to be distributed on river banks in a sequence of community zones from the water’s edge to the outer riparian area. The interplay between flow and landscape is thought to drive the existence of these zones, and specifically, between a lower zone that is inundated most years and an upper zone that is inundated less frequently. There remains no consensus on the number of zones present, what their links to flow might be or whether the same zones occur in different basins. This paper reports on the number and nature of vegetation zones along South African rivers in different geographical areas and their relationship to the flow regime. River bank sites in four climatic areas of South Africa were found to support four vegetation zones (in two groups) despite major differences in vegetation community types, climate and patterns of river flow. The Wet bank and Dry Bank zones were separated at an elevation that correlated well with the 1:2 year flood line. If vegetation zones along rivers can be linked in this generic way to the flow regime of a river, it will strengthen our ability to predict vegetation changes likely to occur with flow modifications.
Hydrological responses of a valley-bottom wetland to land-use/land-cover change in a South African catchment: making a case for wetland restoration
11 September 2015
Stellenbosch University

Rebelo, A.J.;Le Maitre, D.C.;Esler, K.J.;Cowling, R.M.

Valley-bottom wetlands are valuable assets as they provide many ecosystem services to mankind. Despite their value, valley-bottom wetlands are often exploited and land-use/land-cover (LULC) change results in trade-offs in ecosystem services. We coupled physically based hydrological modeling and spatial analysis to examine the effects of LULC change on water-related ecosystem services in the Kromme catchment: an important water-providing catchment for the city of Port Elizabeth. LULC scenarios were constructed to match 5 different decades in the last 50 years to explore the potential effects of restoring the catchment to different historic benchmarks. In the Kromme catchment, valley-bottom wetlands have declined by 84%, driven by key LULC changes: an increase in irrigated land (307 ha) and invasion by alien trees (336 ha). If the wetlands were restored to the relatively pristine extent and condition of the 1950s, riverflow could increase by approximately 1.13 million m3/a, about 6% of the current supply to Port Elizabeth. Wetland restoration would also significantly improve the catchment’s ability to absorb extreme rainfall events, decreasing flood damage. We conclude that in the face of the water scarcity in this region, all ecosystem services, particularly those related to water flow regulation, should be taken into account by decision makers in charge of land zonation. Zonation decisions should not continue to be made on the basis of provisioning ecosystem services alone (i.e. food provision or dam yield). We recommend prioritization of the preservation and restoration of valley-bottom wetlands providing water-related ecosystem services to settlements downstream.
Response of instream animal communities to a short-term extreme event and to longer-term cumulative impacts in a strategic water resource area, South Africa
16 May 2016
Stellenbosch University

Foord, S.H.;Fouche, P.S.O.

Disturbance plays an integral part in generating heterogeneity required for ecosystem persistence, but the increased amplitude and duration of disturbances linked to drivers of global change could result in ecosystem shifts or collapse. Biomonitoring over time provides insights into trajectories of ecosystem change. The responses of two instream animal taxa to two contrasting disturbance events, a major flood event and the long-term cumulative effects of land-use changes, were assessed in 1999–2012 by quantifying variation and change in abundance of functional groups based on flow rate sensitivity, water quality and metrics of ecological condition. All metrics recovered to pre-flood conditions within seven months after the flood event. Similarly, cumulative impacts of land use effected significant decreases in some but not all metrics. Indices that did not change, including SASS total score and ASPT, were the result of insufficient consideration of the decrease in the abundance of sensitive taxa specifically, and the abundance of all taxa in general. The decrease in abundance of sensitive taxa could signal imminent collapse in certain metrics. Evidence is also provided for a shift in the structure of fish assemblages linked to the decrease and loss of taxa sensitive to ecosystem degradation caused by the longer-term impacts of land-use change.
Long-term physical, chemical and biological changes in a small, urban estuary
27 June 2016
Stellenbosch University

Viskich, M.;Griffiths, C.L.;Erasmus, C.;Lamberth, S.

The Diep River estuary, a small estuary in suburban Cape Town, South Africa, has been subject to disturbance for centuries. Several earlier studies have documented conditions in the system, providing baselines against which to measure more recent changes. This study: (i) describes major physical and hydrological changes that have occurred within this estuary; (ii) documents faunistic changes subsequent to earlier biological surveys; and (iii) provides an up-to-date faunal list. Salinity measurements and both invertebrate and fish samples were taken at five stations along the estuary in summer and winter 2014. A census of sandprawn Callichirus kraussi densities was also undertaken to compare with earlier surveys. Developments within the Diep River catchment and estuary have resulted in extensive changes in flow and salinity regimes, causing marked reductions in summer salinity levels, changes in frequency of mouth closure, and deteriorations in water quality. These have resulted in major changes in faunal composition and distribution, including an increase in numbers of non-indigenous species. Surveys in the early 1950s recorded 47 invertebrate species, whereas only 23 were found in 1974. A total of 23 species were again recorded in 2014, but these included several freshwater forms not previously reported, which had entered the system due to lowered salinity values, as well as new alien introductions. Only six of the 69 taxa recorded were reported by all three surveys. There have been substantial declines in sandprawn abundance, from 40 million in 1998 to just over 12 million in 2014. In all, 12 fish species were recorded in the 1950s, nine in 1974, but only five in 2014, including the newly detected invasive mosquito fish Gambusia affinis and the translocated tilapia Tilapia sparrmanii. Thus, only three of the original native fish species remain. Contrary to these losses, the present bird fauna appear to be more abundant and diverse than previously. Regular monitoring is recommended to obtain a clearer understanding of ongoing changes, and major management interventions will be needed if further degradation is to be prevented.
Spatio temporal population dynamics of the invasive diatom Didymosphenia geminate in central-southern Chilean rivers
28 September 2016
Stellenbosch University

Montecino, V.;Molina, X.;Bothwell, M.;Munoz, P.;Carrevedo, M.L.;Salinas, F.;Kumar, S.;Castillo, M.L.;Bizama, G.;Bustamante, R.O.

We document the distribution of Didymosphenia geminata in central-southern Chilean rivers and identify the chemical and physical factors associated with its presence/absence (p/a). Repeated surveys in five successive years provided evidence that D. geminata could be nearing a biogeographic equilibrium in the region. D. geminata databases from extensive biological and environmental surveys in 187 rivers,within ten catchments, south of 38°S commenced in November 2010 and ran through May 2013. In addition, data from two other field surveys were used. The sites evenly distributed latitudinally were climatically characterized. The recent sampling program, following a published species distribution model, was designed to explore D. geminata distribution within thirteen catchments (34°S–48°S). An extensive river survey in 2014 (spring-summer) and in 2015 (autumn) included the p/a, and relative abundance of D. geminata cells in phytobenthos and in the drift. These p/a results showed that the probability of re-encountering D. geminata cells at sites where the species was previously found was significantly highwhile the probability of finding D. geminata cells at sites previously without the species was significantly low. This suggests that the distribution of D. geminata cells among suitable habitats was nearing completion. The relative abundance of D. geminata cells in the phytobenthos versus in the drift indicates seasonality with higher proportion of cells in the phytobenthos during the spring-summer than during the autumn. During the final surveys, principal component analysis of chemical and physical characteristics of rivers showed significant differences between rivers with and without D. geminata. Based on our observations of the distribution of D. geminata cells among rivers with suitable habitat conditions and the fluctuating rate of spread between rivers,we conclude that D. geminata is probably in the ending stage of its spatial demographic expansion in Chile surmounting the different barriers of the invasive process.
Integrating age structured and landscape resistance models to disentangle invasion dynamics of a pond-breeding anuran
14 August 2017
Stellenbosch University

Vimercati, G.;Hui, C.;Davies, S.J.;Measey, G.J.

Modelling population dynamics of invasive species may help to propose effective management countermeasures. Invasion dynamics generally show recursive patterns across species and regions, where initial lag is followed by spread and eventual dominance phases. However, timing and modes of these phases are highly variable, emerging from the interplay between traits of the invader and characteristics of the invaded landscape. Disentangling this interplay is particularly arduous in species with complex life-histories, where an individual passes through different life stages that alter physiology, behaviour and interactions with the environment. Here, we describe an age structured model that can be utilized to simulate population dynamics of invasive pond-breeding anurans. The model follows a spatially structured population approach, each pond representing a discrete habitat patch that exchanges individuals with other similar patches, and simulates change in survival and dispersal behaviour as a function of age.It also integrates dispersal with landscape complexity through landscape resistance modelling to depict functional connectivity across the pond network. Then we apply the model to a case study, the invasion of the guttural toad Sclerophrys gutturalis in Cape Town, first detected in 2000. Age-structured demographic and spatial dynamics of the focal population are reconstructed in a network of 415 ponds embedded in a heterogeneous landscape. Parameterization is conducted through field and laboratory surveys, a liter-ature review and data collected during an ongoing extirpation from 2010. We use the model to explore:i) occurrence and duration of lag phase; ii) whether the spatial spread fits an accelerating or a lineartrend; iii) how simulated dynamics match field observations. Additionally we test model sensitivity to demographic and behavioural traits. We found a lag phase in both demographic and spatial dynamics;however the lag duration of these dynamics does not coincide, where invaders start to spread across thepond network five years before the demographic explosion. Also, we found that the spatial spread fits an accelerating trend that causes complete invasion of the network in six years. Such dynamics noticeably match field observations and confirmed patterns previously detected in other invaders characterized by high dispersal abilities. Sensitivity analysis suggests that it would have been preferable to quantify initial propagule size and post-metamorphic survival in the field; both timing and modes of invasion are par-ticularly sensitive to these parameters. We conclude that the model has potential to forecast amphibian invasion dynamics and test management countermeasures.
Using genetics to prioritise headwater stream fish populations of the Marico barb, Enteromius motebensis Steindachner 1894, for conservation action
14 August 2017
Stellenbosch University

van der Walt, K.-A.;Swartz, E.R.;Woodford, D.;Weyl, O.

South Africa has a relatively large number of threatened freshwater fish species and limited resources to implement conservation programs. Enteromius motebensis was regionally prioritised for action because of its conservation status and flagship status in a nationally important aquatic ecosystem. Genetic diversity of E. motebensis in headwater refugia of the Groot Marico River Catchment was assessed to determine if genetic diversity is important for conservation planning for this species. The results of the genetic analysis indicate that some prioritisation was possible, with two populations showing evidence of recent isolation. Conservation implications: We recommend that at least three populations be prioritised for conservation action to ensure maintenance of most of the remaining genetic diversity of the species.
The ecological integrity of the lower Olifants River, Limpopo province, South Africa: 2009-2015-Part B: Tributaries of the Olifants River
06 October 2017
Stellenbosch University

Marr, S.M.;Mohlala, T.D.;Swemmer, A.

Monitoring on the Lowveld reaches of the Olifants River, Limpopo River System, and its Steelpoort, Blyde, Klaserie and Selati tributaries was initiated in 2009. Analysis of the 2009–2015 data from four Olifants River sites showed deterioration in the river’s ecological condition between where it enters the Lowveld and where it enters the Kruger National Park, with a slight recovery within the Kruger National Park. Physico-chemical, aquatic macroinvertebrate and fish data collected in 2009–2015 at six sites on the Steelpoort, Blyde, Klaserie and Selati tributaries of the Olifants River corroborated the ecological condition of these tributaries. The Selati was the most polluted and was in a critically modified condition, whereas the Klaserie and Steelpoort were in fair condition and the Blyde was in good condition. The Selati appeared to have a significant negative impact on the water quality, macroinvertebrates and fish of the Olifants River within the Kruger National Park.
The ecological integrity of the Lower Olifants River, Limpopo province, South Africa: 2009-2015-Part A: Olifants River main stem
06 October 2017
Stellenbosch University

Marr, S.M.;Mohlala, T.D.;Swemmer, A.

The major rivers of the South African ‘Lowveld’ (low-latitude savanna) suffer numerous impacts from upstream economic activities. Whereas monitoring these rivers is required to detect biodiversity losses, record pollution events and devise mitigation strategies, current monitoring programmes are inadequate. In 2009, the South African Earth Observation Network initiated an intensive long-term research programme on the Lowveld reaches of the Olifants River. Physico-chemical parameters, aquatic macroinvertebrates and fish abundances were recorded at four Lowveld sites in the Olifants River. We review six years of this programme. The results suggest deterioration in the ecological condition of the Olifants River with no discernible improvement through protected areas. Trends could not be detected. The parameters measured, sampling methods and/or sampling frequency might be responsible for the limited trends observed, or alternatively the results simply reflect stable conditions despite on-going pollution. Real time monitoring and an expansion in the parameters monitored would add value to the monitoring programme.
Does restricted access limit management of invasive urban frogs?
19 December 2017
Stellenbosch University

Vimercati, G.;Davies, S.J.;Hui, C.;Measey, J.

Management recommendations that target urban invaders should consider environmental and socio-economic aspects peculiar to the urban landscape. Urbanization often leads to the fragmentation of the invaded landscape into subunits inaccessible to managers (restricted access) or for which detailed information is lacking. Using models to explore impact of these limitations on management success provides a useful approach to propose effective counter measures. Here we deploy a spatially explicit age-structured model applied to a pond network to investigate how restricted access and lack of detailed information may affect management of three invasive anuran species across a peri-urban landscape. The target species, the guttural toad Sclerophrys gutturalis, the African clawed frog Xenopus laevis and the painted reed frog Hyperolius marmoratus, belong to different ecotypes (terrestrial, aquatic and arboreal, respectively) and have different life history traits. We show that restricted property access significantly constrains management success in two of the three species (the guttural toad and the painted reed frog), while lack of detailed information around the invaded landscape impedes successful management in only one species (the guttural toad). The species-dependent response we detected is due to contrasting demographic and spatial invasion dynamics linked to the different anuran ecotypes. Our work highlights the necessity to adopt a context-dependent approach when proposing management recommendations in urban environment.
Achieving the national development agenda and the Sustainable Development Goals(SDGs) through investment in ecological infrastructure: A case study of South Africa
04 April 2018
Stellenbosch University

Cumming, T.L.;Shackleton, R.T.;Forster, J.;Dini, J.;Khan, A.;Gumula, M.;Kubiszewski, I.

Ecological infrastructure (EI) refers to ecosystems that deliver services to society, functioning as a nature-based equivalent of, or complement to, built infrastructure. EI is critical for socio-economic development, supporting a suite of development imperatives at local, national and international scales. This paper presents the myriad of ways that EI supports sustainable development, using South Africa and the South African National Development Plan as a case study, linking to the Sustainable Development Goals on a global level. We show the need for EI across numerous development and sustainability issues, including food security, water provision, and poverty alleviation. A strategic and multi-sectoral approach to EI investment is essential for allocating scarce public and private resources for achieving economic and social-ecological priorities. Opportunities to unlock investment in EI, both internationally and on the national level, are identified. This includes leveraging private sector investment into landscape management and integrating the costs of managing EI into public sectors that benefit directly from ecosystem services, such as the water sector and infrastructure development. Additionally, investing in EI also aligns well with international development and climate change funds. Investment in EI from a range of innovative sources supports global and national development, while complementing other development investments.
Collaborative learning to unlock investments for functional ecological infrastructure: Bridging barriers in social-ecological systems in South Africa
04 April 2018
Stellenbosch University

Angelstam, P.;Barnes, G.;Elbakidze, M.;Marais, C.;Marsh, A.;Polonsky, S.;Richardson, D.M.;Rivers, N.;Shackleton, R.T.;Stafford, W.

Maintenance of functional ecological (or green) infrastructure is threatened by habitat conversion, fragmentation and loss, water scarcity, invasive species, climate change, resource extraction, poor policy implementation and societal inequity. Using South Africa as a case study, our transdisciplinary team identified actions likely to be effective in scaling up research and development projects that support implementation of policy about ecological infrastructure by active adaptive management. Based on expert knowledge at three scales, we analysed South Africa's opportunity to active adaptive management and to unlock investments that enhance functional ecological infrastructure. Barriers included lack of trust among actors, limited collaborative governance and integrated planning, including local partnerships; as well as a poor inclusion of evidence based knowledge based on monitoring of landscape restoration efforts and its social and ecological consequences. Bridges include practicing transdisciplinary knowledge production, enhancing social learning among actors and stakeholders, and advocacy based on improved understanding. We propose a portfolio of place-based actions that could help to facilitate unlocking investments for functional ecological infrastructure by prioritising conservation, management and restoration through integrated cross-scale, collaborative and multi-sector spatial planning. Understanding the structure and dynamics of social-ecological systems, identifying champions, framing key messages for different audiences, and sharing failures and success stories internationally, are crucial requirements to unlock investments.
Quantification of water purification in South African palmiet wetlands
24 January 2019
Stellenbosch University

Rebelo, A.J.;Emsens, W.-J.;Esler, K.J.;Meire, P.

Despite the importance of water purification to society, it is one of the more difficult wetland ecosystem services to quantify. It remains an issue in ecosystem service assessments where rapid estimates are needed, and poor-quality indicators are overused. We attempted to quantify the water purification service of South African palmiet wetlands (valley-bottom peatlands highly threatened by agriculture). First, we used an instantaneous catchment-scale mass balance sampling approach, which compared the fate of various water quality parameters over degraded and pristine sections of palmiet wetlands. We found that pristine palmiet wetlands acted as a sink for water, major cations, anions, dissolved silicon and nutrients, though there was relatively high variation in these trends. There are important limitations to this catchment-scale approach, including the fact that at this large scale there are multiple mechanisms (internal wetland processes as well as external inputs) at work that are impossible to untangle with limited data. Therefore, secondly, we performed a small field-scale field survey of a wetland fragment to corroborate the catchment-scale results. There was a reasonable level of agreement between the results of the two techniques.We conclude that it appears possible to estimate the water purification function of these valley-bottom wetlands using this catchment-scale approach.
The influence of distance to perennial surface water on ant communities in Mopane woodlands, northern Botswana
11 March 2019
Stellenbosch University

Dalerum, F.;Retief, T.A.;Havemann, C.P.;Chimimba, C.T.;van Rensburg, B.J.

Studies of biodiversity along environmental gradients provide information on how ecological communities change in response to biotic and abiotic factors. For instance, distance to water is associated with several factors that shape the structure and the functioning of ecosystems at a range of spatial scales. We investigated the influence of distance to a perennial water source on ant communities in a semi‐arid savanna in northern Botswana. Ant abundance, taxonomic richness, and both alpha and beta diversity were generally higher during the wet than the dry season. However, there were strong seasonal influences on the effects of distance to water, with more pronounced effects during the wet season. While both abundance and beta diversity declined with increasing distances to water during the wet season, there was a contrasting increase in alpha diversity. There was no major effect of distance to water on taxonomic richness during either season. Beta diversity was as high across as along gradients, and we found support for modular rather than nested community structures along gradients. Our study demonstrated that small‐scale gradients in distance to water can influence several aspects of ant communities in semi‐arid savannas. However, our results also point to strong effects of small‐scale environmental variation, for instance associated with vegetation characteristics, soil properties, and plant community structure that are not directly linked to water access.
Impacts of alien plant invasions on water resources and yields from the Western Cape Water Supply System (WCWSS)
10 December 2019
Stellenbosch University

Le Maitre, D.;Gorgens, A.;Howard, G.;Walker, N.

A key motivation for managing invasive alien plant (IAP) species is their impacts on streamflows, which, tor the wetter half of South Africa, are about 970 m(3).ha(-1).a(-1) or 1 444 mill.m(3).a(-1) (2.9% of naturalised mean annual runoff), comparable to forest plantations. However, the implications of these reductions for the reliability of yields from large water supply systems are less well known. The impacts on yields from the WCWSS were modelled under three invasion scenarios: 'Baseline' invasions; increased invasions by 2045 under 'No management; and under 'Effective control' (i.e. minimal invasions). Monthly streamflow reductions (SFRs) by invasions were simulated using the Pitman rainfall-runoff catchment model, with taxonspeci tic mean annual and low-flow SFR factors for dryland (upland) invasions and crop factors for riparian invasions. These streamflow reduction sequences were input into the WCWSS yield model and the model was run in stochastic mode for the three scenarios. The 98% assured total system yields were predicted to be +/- 580 million m(3).a(-1) under 'Effective control', compared with +/- 542 million niLa under 'Baseline' invasions and +/- 450 mill. m(3).a(-1) in 45 years' time with 'No management'. The 'Baseline' invasions already reduce the yield by 38 mill.m(3).a(-1) (two thirds of the capacity of the Wemmershoek Dam) and, in 45 years' time with no clearing, the reductions would increase to 130 mill. m(3).a(-1) (capacity of the Berg River Dam). Therefore I A P-related SFRs can have significant impacts on the yields of large, complex water supply systems. A key reason for this substantial impact on yields is that all the catchments in the WCWSS are invaded, and the invasions are increasing. Invasions also will cost more to clear in the future. So, the best option for all the water-users in the WCWSS is a combined effort to clear the catchments and protect their least expensive source of water.
Reconstruction of the historical distribution ranges of imperilled stream fishes from a global endemic hotspot based on molecular data: Implications for conservation of threatened taxa
27 February 2020
Stellenbosch University

Chakona, A.;Gouws, G.;Kadye, W.T.;Jordaan, M.S.;Swartz, E.R.

Understanding historical distribution patterns of freshwater fishes prior to human impacts is crucial for informing effective strategies for biodiversity conservation. However, incomplete information on species occurrence records, the existence of cryptic species and sensitivity to small sample sizes limit the application of historical records in natural history collections as well as conventional species distribution modelling algorithms to infer past distributions of species. This study used molecular data as an alternative and objective approach to reconstruct the historical distribution ranges of four stream fishes from the Breede River system in the Cape Fold Ecoregion, a global hotspot of imperilled endemic freshwater biodiversity in southern Africa. The study used 249 occurrence records and 208 mitochondrial cytochrome b sequences to reconstruct the potential historical ranges of four taxa: Galaxias sp. 'zebratus nebula', Galaxias sp. 'zebratus Riviersonderend', Pseudobarbus sp. 'burchelli Breede' and Pseudobarbus skeltoni. All four taxa historically had broader distribution ranges across the Breede River system before human impacts, but they have suffered severe attrition as the main-stem populations have been extirpated. The severe decline in the historical ranges of these four taxa is a result of multiple impacts, particularly hydrological modification, habitat degradation and the introduction of non-native species, which are also global challenges for freshwater ecosystems. The approach presented in this study has great potential for reconstructing historical ranges of stream-dwelling taxa from disparate regions where fragmentation has resulted from human-mediated impacts. This information is crucial for identifying appropriate conservation strategies such as river rehabilitation and eradication of non-native species, as well as guiding reintroductions and informing assisted gene flow where these are deemed necessary interventions.
Do salamanders limit the abundance of groundwater invertebrates in subterranean habitats?
05 June 2020
Stellenbosch University

Manenti, R.;Lunghi, E.;Barzaghi, B.;Melotto, A.;Falaschi, M.;Ficetola, G.F.

Several species of surface salamanders exploit underground environments; in Europe, one of the most common is the fire salamander (Salamandra salamandra). In this study, we investigated if fire salamander larvae occurring in groundwater habitats can affect the abundance of some cave-adapted species. We analyzed the data of abundance of three target taxa (genera Niphargus (Amphipoda; Niphargidae), Monolistra (Isopoda; Sphaeromatidae) and Dendrocoelum (Tricladida; Dedrocoelidae)) collected in 386 surveys performed on 117 sites (pools and distinct subterranean stream sectors), within 17 natural and 24 artificial subterranean habitats, between 2012 and 2019. Generalized linear mixed models were used to assess the relationship between target taxa abundance, fire salamander larvae occurrence, and environmental features. The presence of salamander larvae negatively affected the abundance of all the target taxa. Monolistra abundance was positively related with the distance from the cave entrance of the sites and by their surface. Our study revealed that surface salamanders may have a negative effect on the abundance of cave-adapted animals, and highlited the importance of further investigations on the diet and on the top-down effects of salamanders on the subterranean communities.
Water-use characteristics of Palmiet (Prionium serratum), an endemic South African wetland plant
06 November 2020
Stellenbosch University

Rebelo, A.J.;Jarmaln, C.;Esler, K.J.;Cowling, R.M.;Le Maitre, D.C.

Palmiet, Prionium serratum, is an endemic wetland plant which dominates oligotrophic wetlands throughout the Cape Floristic Region, South Africa. Palmiet is often perceived as undesirable by landowners, in part because it is thought to have high water-use, although little is known about the water-use of this important wetland species. We estimated the water-use dynamics of Palmiet at the leaf scale, using stomatal conductance measurements, and at the wetland scale, by modelling evapotranspiration using remote sensing and an energy-balance model. Factors that influenced Palmiet water-use were also considered, and seasonal variations were analysed. The aim was to estimate Palmiet wetland water-use, and to develop a set of crop factors (Kc) for use in hydrological modelling of catchments containing Palmiet wetlands. Results show that Palmiet has a comparatively low stomatal conductance (11–152 mmol∙m-2∙s-1), which was lower in summer than winter, and moderate evapotranspiration for a riparian species (1 220 mm∙a-1 compared to a local reference evapotranspiration of 1 302 mm∙a-1 and A-Pan evaporation of 2 809 mm∙a-1), which was higher in summer (more energy to drive evapotranspiration and higher vapour pressure deficits). Morphological and physiological adaptations to nutrient poverty or periodic drought are suggested theories which may explain the controls on transpiration for Palmiet.
The right of access to adequate water [discussion of Mazibuko v The City of Johannesburg Case no 13865/06]
01 September 2009
North West University

Jansen van Rensburg, Linda

The Constitution of the Republic of South Africa, 1996 guarantees everyone the right to access to adequate water and places an obligation on the state to take reasonable measures, within its available resources, to achieve the progressive realisation of this right. This discussion focuses on the possible implications of the recent High Court case of Mazibuko v The City of Johannesburg case no 13865/06 for socio-economic jurisprudence in South Africa.
Physical and chemical characteristics of thermal springs in the Waterberg area in Limpopo Province, South Africa
02 September 2009
North West University

Van der Walt, Izak J.;Olivier, J.;Van Niekerk, H.J.

The Limpopo Province in South Africa is richly endowed with thermal springs. Some have been developed for recreational, tourism or other purposes, while a number remain completely undeveloped. If the full economic potential of springs can be realised in a sustainable manner, they could make a substantial contribution to the local or even regional economy. The optimal use of a thermal spring is largely dependent upon its physical and chemical characteristics. This article focuses on the temperature and chemical features of 8 selected thermal springs located in the southern (Waterberg) region of the Limpopo Province, namely Warmbaths, Loubad, Vischgat, Die Oog, Rhemardo, Lekkerrus, Libertas and Buffelshoek. All of these springs are of meteoric origin, with water temperatures ranging from 30oC to 52oC. The mineral composition of the thermal waters reflects the geological formations found at the depth of origin. Changes in land use that occurred over the past few decades have apparently had no impact on the physical and chemical properties of the thermal spring waters. This effect may, however, become evident at a later stage due to a time lag in the migration of contaminants. The fluoride concentration of water from seven of the eight springs (all except Loubad) does not conform to domestic water quality guidelines and makes the water unfit for human consumption. Unacceptably high values of mercury were detected at Libertas. It is recommended that strict monitoring of the concentration of fluoride and other potentially harmful elements should be mandatory whenever the thermal spring water is used for bottling, domestic or full-contact recreational purposes.
On the use of diatom-based biological monitoring Part 2: A comparison of the response of SASS 5 and diatom indices to water quality and habitat variation
02 September 2009
North West University

Van Rensburg, Leon;De la Rey, Pieter Arno;Roux, H.;Vosloo, A.

Due to the fact that South Africa is a water-scarce country, integrated water resource management based on sound information is essential. Bio-indicators have provided valuable information for water resource management in recent years and have enjoyed increasing popularity. Bio-indicators especially stepped to the forefront with the realisation that aquatic eco-systems are not only a source of water but also deliver several goods and services, as well as being essential for industrial growth and quality of life of many South Africans. This study aimed to quantitatively test two kinds of biomonitoring tools namely diatom-based (SPI and BDI) and macro-invertebrate based (SASS 5) in order to assess their applicability in South African River systems; and whether any additional information can be gained by using the two tools in tandem. The results showed that diatom indices are affected more by changes in water quality than SASS 5, while SASS 5 displayed a higher dependency on habitat quality, as measured by IHAS, than the diatom indices. It is therefore suggested that the two indices be utilised as complementary indicators for integrated assessment of river health.
A physical environmental management perspective on municipal water supply: proposals for Tlokwe City Council
17 December 2009
North West University

Nealer, Eric;Raga, Kishore

All South Africans, especially, those involved with the development and management of its water resources should be aware that South Africa is generally an arid to semi-arid region, with an average rainfall of approximately 500 mm per annum, compared to a world average of 860mm. Consequently, potable water is a very scarce resource, and is often the biggest prohibiting factor for development of, for example, new residential areas in a town or city. Hence a public service rendering municipality like the Tlokwe (Potchefstroom) City Council will have to, in its quest to manage its potable water supply more effectively, efficiently and economically, take cognisance of aspects such as: · The origin of its potable water; · The nature and extent of the storage and treatment of the potable water; · The manner in which the potable water is distributed to the users and consumers; and · The manner in which the wastewater is collected, treated and managed. The authors of this article are of the opinion that the aforementioned can only be taken care of effectively by incorporating a physical environmental management perspective in its municipal governance.
Using a transdisciplinary approach for environmental crisis research in History
06 August 2010
North West University

Van Eeden, Elize S.

Although it is true that each local area or region possesses its own historiography – and for that matter its own environmental historiography – there should not be much difference in the research methodology, sources and pitfalls or drawbacks of doing environmental history research in labelled environmental crisis areas. This article presents a concise historiography on dealing with environmental crisis in literature is provided. This is followed by a proposed transdisciplinary (TD)-methodological structure that can serve as a guideline to specifically to environmental historians, and perhaps other disciplines in the humanities, that studying local or regional environmental crises. A local environment in South Africa, namely the Far West Rand, serves as an example for conducting TD research that features an environmental crisis. The paper concludes by also, amongst others, suggesting that environmental historians and other environmental experts in a variety of fields and disciplines in South Africa and Africa should form an Environmental Studies Association to support one another, particularly in their efforts to work together in interdisciplinary and transdisciplinary ways with researchers from a broad range of academic fields. This paper therefore serves merely as a debate to open up discussions for refining the perspectives and existing methodologies of research in environmental history.
A short comparative history of wells and toilets in South Africa and Finland
07 January 2011
North West University

Haarhoff, Johannes;Juuti, Petri;Mäki, H

This paper describes the technological development of wells and toilets and the cultural practices related to them in two countries, South Africa and Finland, from the Middle Ages to modern times. Wells and toilets have always been linked to the well-being of humans and they still are the most common technical systems in the service of mankind. They are simple to build, but if they are constructed improperly or stop functioning properly, they may endanger the health of both humans and the environment. The solutions used for getting clean water or for disposal of excrement have always been a matter of life and death for human settlements. Located on opposite sides of the world, the climate and natural resources of South Africa and Finland are very different. However, surprisingly similar solutions, for example wind turbines to pump water, have been used in rural areas. Furthermore, urbanization and industrialization occurred in both countries at approximately the same time in the 19th century, which caused increasing environmental problems in Finnish and South African urban areas. The transition to modern water supply and waste disposal systems was a very demanding process for municipal administrations in both countries.
Aspects of irrigation development in the Netherlands East Indies
07 January 2011
North West University

Ertsen, Maurits W

The ‘Romijn’ discharge measurement structure was developed in the Netherlands East Indies. By the end of the colonial period in the 1930s, it had become the standard structure in irrigation. The Romijn design is not only still the main discharge measurement structure in Indonesia, it is also used in Dutch water management practice and education. The question of continuity is at the heart of concepts such as ‘technological tradition’ or ‘technological regime’, and this continuity links the information embodied in a community of practitioners with the hardware and software the members master. Such communities define accepted modes of technical operation. Engineering education is an important mechanism in preference-guided selection of design solutions, and obtaining an engineering degree is much like passing the preparatory requirements for community membership. When, in 1967, a civil engineering student from Delft Polytechnic presented his final paper for an irrigation design to his supervisors, the first question they asked was why he had not used a Romijn weir as an off-take structure. The Dutch irrigation regime, which consists of the explicit and implicit rules of Dutch irrigation design, is the central subject of this paper. In this paper I shall discuss two related issues: (1) how the Netherlands East Indies irrigation regime developed, and (2) how the (dis)continuities in irrigation education and practice following Indonesian independence can be understood. Naturally, while discussion of these issues, to a certain extent at least, depends on the data available, it also depends on the researcher’s perspective.
Some human actions in the destruction and construction of culture and nature – the Merafong region as a case study
10 January 2011
North West University

Van Eeden, Elize S

For at least the past 180 years the Merafong Municipal region in the Gauteng Province of South Africa, (of which the Wonderfontein Catchment forms a part) has strongly relied on the primary sector for its economic existence and development. In the process some human actions, also related to serious water contamination/pollution, have resulted in phases of constructions1 as well as economic and health destructions. Differences over whose environment and whose nature it is spontaneously developed, with sometimes less friendly outcomes. The ‘end result’ up to 2006 is a complicated scenario experience, similar to that of many other regions or local areas, but also very unique and somewhat frightening. The long term focus of this article is to exchange knowledge2 on the region with the objective to contribute towards creating a sustainable environment by ensuring closer co-operation between the various economic active cultures operating or functioning in the Merafong municipal region. In this article four aspects are covered.
Water and the human culture of appropriation: the Vaal River up to 1956
10 January 2011
North West University

Tempelhoff, J W N

There is discernable evidence of the human presence having historically appropriated the 1300 kilometer long Vaal River of South Africa as it extends itself from the Drakensberg Plateau into the arid Karoo region. This hard-working tributary of the Orange River, which was instrumental as a supply of water to the Witwatersrand, in the era of the region’s gold mines, has been used by humans in a variety of ways. First it was used as a route of communications, then as a borderline demarcating the territorial spaces of states and colonies. Later it was used for purposes of economic development. In the study the objective is to point towards the manner in which humans have influenced the river and its hinterland, particularly from the nineteenth century, up to the 1950s. The process of appropriation, it is argued, has had a different effect when humans laid claim to the river and its environment for social, economic and political purposes.
The Vaal River Barrage, South Africa’s hardest working water way: an historical contemplation
11 January 2011
North West University

Tempelhoff, J.W.N.;Munnik, Victor;Viljoen, Morné

South Africa’s Vaal River is the country’s hardest working rivers. It has been instrumental in securing valuable water supplies in the development of the country’s economic hub – the Gauteng Province. Since the mid-twentieth century there have been increasing indications of water pollution threatening the storage facility of the Vaal River Barrage, built by the water utility, Rand Water, at the start of the twentieth century. Currently, as a result of a variety of factors, untreated wastewater is posing a severe environmental threat in the Vaal River Barrage Catchment area. In the article attention is given to the origins of pollution and recent events that had the effect of mobilising grassroots anger in civil society with the state of affairs. The article forms part of a transdisciplinary research project that is currently conducted at North-West University’s Vaal Triangle campus in Vanderbijlpark.
Hidden benefits of public private partnerships: the case of water pressure management in Sebokeng
12 January 2011
North West University

Mckenzie, R S;Wegelin, W;Mohajaneand, P;Shabalala, S

Many water distribution systems in South Africa are deteriorating due to many years of neglect resulting in a serious maintenance backlog. Recent government legislation has introduced free basic water to all South Africans up to a limit of 6 Kl/month per property which in turn causes certain confusion regarding payment among many residents. These key issues and others have led to serious problems with service delivery specifically in the low income areas where the maintenance has been neglected for more than 30 years in some cases. The potential for support from the Private Sector has been highlighted at the highest levels within government as a possible solution to addressing the existing backlogs despite the fact that there are relatively few successful projects to support this view. This paper presents the results after 30 months of operation of a small scale public private partnership in one of the largest low income areas in South Africa where the Sebokeng/Evaton Pressure Management Project was commissioned in July 2005. The savings both in terms of volume of water saved as well as financial savings to the municipality are impressive and exceed all initial expectations. The most interesting a1spect of the project, however, is not the savings achieved from the installation, but the numerous other additional benefits that have materialised which were not originally anticipated when the project was commissioned. Such benefits, include the identification of many network problems that had been undetected for more than 9 years as well the sudden interest in helping the residents by several government and semi-government organisations. These organisations were unable or unwilling to provide any support to the area prior to the successful Public Private Partnership. The project represents a significant advancement in Public-Private Partnerships (PPP’s) and clearly demonstrates that small scale Public Private Partnerships can be viable despite the general view that this type of project is confined to large scale initiatives due to the effort and expense in developing the PPP type of contract. The paper provides details of the processes involved in setting up and implementing such a project and highlights that the model used by the Project Team to address leakage in Sebokeng and Evaton can be adapted for use in other areas and other applications to improve service delivery throughout South Africa as well as elsewhere in the world where conditions permit. The paper presents the results from the project after the first 30 months of operation and summarises some of the many additional benefits that have arisen from the project.
Water users’ associations from the users’ perspective: local water management at Thabina irrigation scheme, Limpopo, South Africa
13 January 2011
North West University

Orne-Gliemann, Maud

At a time when the South African water department and a circle of water experts in the country are defining their position on water users’ associations (WUAs), this paper looks at people’s actions and perceptions of local water management as a fundamental factor to understanding small farmers’ interactions with these newly established institutions. It presents the preliminary results of a community study conducted at Thabina irrigation scheme, Limpopo, between September 2007 and April 2008. This study offers an original approach to analyzing the scheme’s difficulties and, without providing a representative image of smallholder irrigation schemes in South Africa, it allows for interesting preliminary reflections around small farmers’ perceptions of water management and local water management institutions. The study of perceptions is not new, nor does it belong as an analytical tool to one or other academic discipline. In order to fully grasp this complex and multidimensional object, a transdisciplinary approach is therefore applied and implemented in the field by using an innovative set of methods: interviews, verbal associations and participatory photography. The advantages and difficulties related to the use of a perception and transdisciplinary approach are discussed.
Environmental ethics and crime in the water affairs of the Wonderfontein Spruit Catchment, Gauteng, South Africa
13 January 2011
North West University

Van Eeden, Elize S;Liefferink, M;Tempelhoff, E

This article provides an analysis of the water history regarding the Wonderfontein Spruit Catchment in the former Far West Rand in South Africa. The major scope for discussion is a short analysis of environmental ethics and crime in this area in the past, and how it has affected man and environment as analysed from a 21st Century perspective. The Wonderfontein Spruit Catchment forms part of the present-day Merafong municipal area, formerly Carletonville. Although voices of concern have featured prominently since the 1960s and even earlier, no extraordinary ethical approach towards this environment and its inhabitants is recorded in history. Bibliographic sources of the Wonderfontein Spruit Catchment currently number over 5000 entries. Despite this impressive production resulting from especially research, reports and whistle blowing in the past 55 years, the area was exposed to limited and insufficient ethically inspired actions, that should have had the ingredients to confirm a positive approach by primary role players regarding environmental management.
Privatisation and water governance in Africa: implications of a rights-based approach
13 January 2011
North West University

Olowu, 'Dejo

Early in the post-independence era, the control of water resources in many African states was a task of central planning. Regrettably, water management soon became a miry adventure in most African states largely because of warped planning and implementation. This article examines the phenomenon of private sector involvement in water resources management and seeks to understand the effect of such involvement on the right to water in Africa in the context of the Millennium Development Goals. The article explores the continuing relationship between African governments and non-state actors in the management of water resources in the privatisation age. The article further analyses the role of various national water governance initiatives vis-à-vis the efficient management of water resources and the sharp contradictions in their frameworks from a rights-based perspective. It evaluates the normative frameworks of access to water as a human right in Africa and contends that the human being must be placed at the centre of water discourses in assessing all role actors and their responsibilities. Extrapolating from experiences from various states within and outside Africa, this article advocates a rights-based approach to water issues and its value for the ultimate purpose of humancentred development.
“Crossing over”: appropriate private sector principles, to operate more reliable public sector water services
13 January 2011
North West University

Wall, K

Private sector institutions utilise many different business methods, some of which can selectively be adapted for use by organisations outside the private sector, to the benefit of their service delivery responsibilities. But the best of the appropriate practices from the private sector have often “not crossed over”. The Water Research Commission (WRC) of South Africa, working in collaboration with the Council for Scientific and Industrial Research (CSIR), finds that the concept of franchising, so successfully used by the private sector to deliver many goods and services, if applied to water services operation and maintenance, could alleviate and address many challenges in the management of water services. At the same time, franchising could provide an ideal stimulus to support the development of local enterprises, all within the municipal service delivery environment. Franchisee water service providers, dependent for their livelihood on the success of their business, would have a strong incentive to perform, and would also enjoy the benefit of the franchisor’s expert guidance and quality assurance. Some areas for potential franchising include meter management, billing, plumbing, pressure management, sewer maintenance, and wastewater treatment processes. The help from the franchisor would be of particular value to water services authorities at a distance from the major urban centres. Few of these authorities can afford to employ competent qualified staff, and often non-compliance with the laid down performance standards is a direct consequence of this lack. Significant improvements would soon be seen if the generally under-qualified and under-resourced water services staff could have this ongoing support, mentoring and quality control — or if the authority could enter into partnerships with small local enterprises or NGOs which would, through franchising, enjoy the necessary ongoing support, mentoring and quality control, and would have quick access to expert assistance when they needed it.
Neighbourhood effects and household responses to water supply problems in Nigerian cities
13 January 2011
North West University

Acey, Charisma

Between 1990 and 2004, Nigeria’s urban population jumped to nearly half the national population, while access to improved sources of water in urban areas dropped by nearly 15 per cent during the same period. This paper presents preliminary results on the relationship between water supply, neighbourhood characteristics, and household strategies in response to dissatisfaction with water provision as reported by 389 respondents in 10 neighbourhoods in Lagos and Benin City, Nigeria between October 2007 and February 2008. In this paper, a conceptual model of consumer demand for water is used, based upon Hirschman’s exit, voice and loyalty (EVL) framework. The model explicitly factors in the quality of water provision and variables at the household and neighbourhood levels that could affect perceptions about quality and the strategies that households use to cope with inadequate public services. Preliminary results show that reported household strategies to secure water are affected by community-level factors such as the range, cost, and quality of water supply alternatives, as well as neighbourhood composition. Furthermore, the percentage of urban migrants and households that live in rented flats in a neighbourhood seems to be associated with the use of exit strategies (as opposed to voice) in response to problems with their primary water supply.
Disinfection by-products and extractable organic compounds in South African tap water
14 January 2011
North West University

Nothnagel, C.;Kotte, K.;Pienaar, J.J.;Van Zyl, P.G.;Beukes, J.P.

An important step in urban purification of drinking water is disinfection by e.g. chlorination where potential pathogenic micro-organisms in the water supply are killed. The presence of organic material in natural water leads to the formation of organic byproducts during disinfection. Over 500 of these disinfection by-products (DBPs) have been identified and many more are estimated to form during the disinfection step. Several DBPs such as trihalomethanes (THMs), which is carcinogenic, poses serious health risks to the community. There is very few quantitative data available which realizes the actual levels of these compounds present in drinking water. The levels of four THMs present in drinking water were measured. It included chloroform, bromodichloromethane, chlorodibromomethane and bromoform. Although microbiological parameters are considered to get more attention than disinfection by-products, the measurement of the levels of these compounds in South-African drinking water is essential together with establishing minimum acceptable concentration levels. The target range for total trihalomethanes (TTHMs) established by the US EPA at the end of 2003 is 0-0.08ug/mL. The aim of this paper is to create an awareness of the problem as well as presenting preliminary results obtained with the method of analysis. Preliminary results indicate that urgent attention must be given to the regulation and monitoring of DBPs in South African drinking water.
Black workers, typhoid fever and the construction of the Berg River – Saldanha military water pipeline, 1942 – 1943
14 January 2011
North West University

Visser, G E;Monama, F L

War creates a huge need for labour to support the war efforts of the belligerent parties. In South Africa tens of thousands of ‘non-white’ workers were mobilised during the Second World War to satisfy the Union Defence Force’s (UDF’s) labour needs at home and abroad. This article, firstly, outlines the role of ‘non-white people’, particularly black Africans, in the UDF with special reference to those employed within the Union of South Africa. Secondly, it briefly delineates typhoid fever as an historical thorn in the flesh of military forces up to the early 20th century. It then looks briefly into the incidence of and perceptions on typhoid fever as a killer disease in South Africa on the eve of the Second World War. Against that background, the article investigates the employment of black workers on the construction of the Berg River-Saldanha Bay military water pipeline and the UDF’s response to the threat and subsequent outbreak of typhoid fever amongst the workers at the Berg River intake site in 1943. The article concludes that the public health authorities and UDF were aware of the threat of typhoid fever with regard to the Berg River water scheme, but did not take sufficient precautionary measures, which could have had serious repercussions for the Allied war effort. This incident should serve as a warning to the South African National Defence Force when deploying on peace support operations on the African continent where typhoid fever remains a serious threat next to Hiv/Aids.
Controlling the farmer: colonial and postcolonial irrigation interventions in Africa
14 January 2011
North West University

Ertsen, Maurits W

Aiming at full control over farmer actions was a shared characteristic of colonial irrigation engineering approaches. However, the way control was sought in African irrigation projects was different from Asian colonies. This paper traces the origins of colonial approaches to irrigation development in Africa and the continuities between colonial and post-colonial approaches. The Kano River Project in Nigeria, part of a larger irrigation development program from the late 1960s and early 1970s, serves as a typical example of a post-colonial irrigation system in which engineers drew upon colonial experiences. The Dutch engineers responsible for developing the system applied technologies from the Netherlands East Indies to regulate water flows in the system. At the same time, they engaged in a debate on how to organize farmers in the project to ensure efficient and rational use of water in irrigated farming. They joined project managers in viewing strong control over farmer production – a central feature of African colonial irrigation projects – as key to success. However, given the social conditions in the Kano area, particularly landownership, this strong control proved difficult to realize.
Conceptualisation of the consequences of land use decisions on water resources in the central region of South Africa: an agent based modelling perspective
14 January 2011
North West University

Woyessa, Y E;Welderufael, W A;Kinyua, J D M

Over the past few decades, numerous researchers have improved measurements of land use change through representation of much more complex processes of land use and its impact on water resources. Understanding the causes of land use change has moved from a simplistic representation of a few driving forces to a much more detailed understanding that involves situation-specific interactions among a large number of factors at different spatial and temporal scales using agent-based models. The agentbased perspective is centred on the general nature and rules of land use decision making by individuals and represents the motivations behind decisions and the external factors that influence decisions about land use. In this paper, an attempt is made to conceptualise the social and biophysical interactions as the driving forces that lead to decisions of land use, and its potential impact on water resource, including factors such as interventions and technologies that influence the decision of land use change in rural agricultural areas. The development of the conceptual model was done through a series of meetings and workshops and by visualising the relationships between the different factors, such as biophysical and socio-economic factors, using a brain mapping technique. The resulting conceptual model illustrates the main domains of the environment, the socioeconomic factors, and captures all the factors and their interaction that lead to decision in land use change. The socio-economic factors and their interaction will be captured by the ABM module while the biophysical factors that have direct impact on runoff and stream flow could be handled by the hydrologic module which will then be integrated into the ABM model. This, however, is a primary effort in the development of an ABM within the Modder River Basin system and needs continues refinement for optimum functionality and simulation of the real world.
The tragedy of the water commons: the case of the Lower Orange water management area
14 January 2011
North West University

Gouws, C M

In the human environment there is a tendency to refer to resources, such as land and water which do not specifically belong to any single individual, as the ‘commons’. Garret Hardin wrote his famous paper called: “The Tragedy of the Commons” in which he highlighted the problem inhabitants of the world face regarding the growing population and depletion of natural resources. He proposed that limits must be placed on the liberal use of natural resources, which usually involve some kind of legislation. South Africa, as a semi-arid country, needs to manage the water as a commons to ensure that all inhabitants of the country have access to safe drinking water as instructed by the Constitution of the Republic of South Africa Act No. 108 of 1996 and subsequently preserved in the National Water Act No 36 of 1998. The significance of Hardin’s theory to South Africa becomes evident in the necessity of the mentioned acts, which involve the establishment of Catchment Management Agencies (CMAs) and Water User Associations (WUAs). These institutions must ensure the involvement of all stakeholders and water users to manage the resource optimally. Establishing these institutions, however, proved to be difficult and their efficiency questioned, thus illustrating a “tragedy within the tragedy”. This article considers the case of the Lower Orange Catchment Management Agency and the Upington Islands Water User Association in the //Khara Hais local municipality, to illustrate the thus far failing efforts taken by this region to manage the water resource.
Recent trends in South African water historiography
14 January 2011
North West University

Tempelhoff, J W N

The discipline of water history is relatively young but since the 1990s there has been growing interest in the field. In this article an exposition is provided on the origins of the discipline of water history as a subdivision of environmental history. The discussion then turns to an outline of recent developments in the historiography of water history in South Africa. Attention is also given to the possibility of extending the study of this discipline into a number of allied fields.
The devil is in the detail – an analysis of the DBSA’s ‘Access to Sanitation’ indicator
18 January 2011
North West University

Ingle, M K

When using indicator values to measure change over an interval of time, the general understanding of the factor being analysed may have been modified during the period under review. Altered definitions of ‘urban’, or ‘poverty’, provide common instances of this phenomenon. This article outlines a similar situation with respect to the ‘access to sanitation’ indicator as it features in the Development Bank of Southern Africa’s series of Development Reports. These publications are often referred to as a ready source of useful information. It is shown how an altered understanding of what constituted ‘sanitation’ in South Africa came to influence the relevant indicator values. This change, if not taken into account, could result in planning calculations yielding invalid conclusions. The article deals with the casual use of ready-to-hand indicators by nonspecialist practitioners, and about how easy it is to be misled on occasion.
Water and the public trust doctrine – a South African perspective
19 January 2011
North West University

Van der Schyff, E.;Viljoen, G.

The legal principles concerning rights to water have been changed considerably by the provisions of the National Water Act 36 of 1998. The National Water Act aims to redistribute water rights to previously disadvantaged people and communities by the introduction and application of a public trust doctrine to South African natural resources law. It is proposed that these legislative measures will ensure that water as a natural resource will be used to the benefit of the nation as a whole. However, the practical application of the public trust doctrine needs to be analysed, especially with the view of determining the actual benefits to poor and deprived people.
The role of science in deepening democracy: the case for water in post-Apartheid South Africa
19 January 2011
North West University

Turton, A

South Africa is a water constrained country with a complex history of resource capture and human rights abuses. Science, as practiced by the national science councils, could play a significant role in deepening our democracy. This paper explores two possible paradigms - one where science is divorced from the national constitution, and the other where our science is embedded in the national constitution. The paper argues that the latter approach would make our national science more relevant, but of necessity would embroil it in issues of historic legacy and therefore become “messy”.
Slow-onset disaster and sustainable livelihoods: the Vaal River in the vicinity of Parys
19 January 2011
North West University

Van Riet, G;Tempelhoff, J W N

This article is based on data gathered during a research project commissioned by the Fezile Dabi District Municipality in the northern part of South Africa’s Free State Province. The research team (which included the authors) was asked to investigate allegations of pollution of tap water, as well as sewage from the local wastewater treatment plant flowing into the Vaal River in the town of Parys on the banks of the Vaal River. The authors adopt a sustainable livelihoods approach in analysing data gathered by way of unstructured interviews in and around Parys in June–July 2008. They argue that actual and perceived levels of pollution are eroding various local livelihood assets and it is posited that the situation constitutes an unfolding slow-onset disaster. It is imperative that shocks such as sewerage spills and rumours of polluted potable water are addressed to ensure that these do not become long-term negative trends.
Legal issues concerning mine closure and social responsibility on the West Rand
20 January 2011
North West University

Van Eeden, Elize S;Liefferink, M;Durand, J F

Mining and, especially, gold and uranium mining have played a major role in the economy, history, and demography of South Africa. The contribution of the mines to the economy of South Africa over the past century has been overvalued, while the social injustices and negative environmental impacts that accompanied mining have been underplayed or ignored by the mining houses and government. The environmental situation has worsened significantly over the past few years due to the abandonment and pending closure of most of these mines. A reluctance is perceived on the part of the mining companies, and even government, to take responsibility for the damage caused by pollution, ecological degradation, and impact on human health by mining. Instead, the current informal policy appears to take smaller companies to court on minor environmental injustices to, perhaps, impress the broader public, while one of the biggest environmental concerns is stylishly treated. The inability of government to address the damage by mines effectively is in conflict with the National Water Act, the National Environmental Management Act, the Mineral and Petroleum Resources Act, the National Nuclear Regulator Act, and the Constitution of South Africa. The authors propose a multidisciplinary approach to address water-related environmental injustices on the West Rand and Far West Rand. We also describe the application of the National Environmental Management Act of South Africa (Act No. 107 of 1998) in the Wonderfonteinspruit and Tweelopiespruit Catchments and the current water quality situation.
Parys on the Vaal.
09 January 2012
North West University

Oberholster, A G

• Opsomming: Parys is in 1876 op die plaas Klipspruit aangelê. Die ontdekking van goud op die Witwatersrand in 1886 het baie vir die vooruitgang van die dorp beteken en in 1890 was dit een van die tien grootste dorpe in die OVS. Die Tweede Vryheidsoorlog het egter alle ontwikkeling tot stilstand gedwing. In 1905 is die spoorlyn na Parys voltooi en in 1910 is 'n dam in die Vaalrivier gebou wat die dorp se landboupotensiaal verhoog en watersportgeriewe geskep het. Verskillende nywerhede en sakeondernemings het mettertyd op die dorp gevestig geraak sodat Parys vandag 'n aantreklike en vooruitstrewende dorp met meer as 8 000 Blanke inwoners is.
Innovation opportunities in irrigation technology for using virtual water in 21st century South Africa: reflections from the past to the present.
13 January 2012
North West University

Nyandoro, Mark

• Summary: In 21st century South Africa, new and old technological innovations in agriculture can be employed to protect existing and future water supplies that are increasingly becoming vulnerable to encroaching global warming trends. The purpose of this article is to identify irrigation technology, the impact on irrigative farming of a polluted water environment through mining and other baneful industrial activities in the Republic. It also aims to discuss innovation opportunities in irrigation technology for using virtual water – a concept commonly associated with the Middle East. South Africa possesses arguably the most sophisticated engineering technology in irrigation in southern Africa. In this article, reflections on irrigation from the past to the present will be complemented by a historical focus of the context in which this farming enterprise evolved. A brief historical synopsis of irrigation shows that this activity which became more technologically advanced in the colonial and post-independence eras was also practiced in the pre-colonial period for food security and as an insurance against drought. Irrigation was practised in South Africa before and after the colonisation of the Cape by the Dutch in 1652. Irrigation technology in the seventeenth century tended to lack the sophistication and modernisation of the contemporary world. Innovative improvements became imperative as the state increasingly became more involved in agriculture from the 1920s and 1930s largely as part of a process leading to the evolution of settler irrigation policy which was premised on capital accumulation and the deprivation of Africans of land ownership rights. This policy orientation clearly changed from the advent of independence to the 21st century in favour of a policy that aimed at economically empowering the Black smallholder sector farmers without necessarily neglecting the largescale commercial producers. Irrigation farming is not a novel phenomenon to the region. Since the turn of the new millennium, technological innovation has been prioritised because South Africa is situated in a predominantly hot arid zone of the sub-region. Total evaporation creates endemic water shortages. It is therefore imperative that water resources are well managed in a country which thrives largely on mining, industrial and agricultural pursuits. Due to South Africa’s geophysical location in one of the world’s arid terrains, irrigation has been identified as an essential corollary to dry land farming and other economic endeavours. Nevertheless, in spite of advances that have been made in centre-pivot manufacturing, South Africa has generally tended to ignore cheaper irrigation methodologies such as the drip, terracing and flood systems which seem more suitable and appropriate in arid conditions. It has also ignored the fact that using large volumes of both riparian and imported water from Lesotho to irrigate a crop like maize in the Eastern Free State Province, for example, is not only unviable but it is also unsustainable. A major rethink of how food supply can be boosted on the basis of irrigated agriculture, utilising more advanced and peculiarly suitable technology in hot and arid or water deficient areas is vital. This is more so because industrial demand for water – a large quantity of which is expensively procured or transferred from Lesotho through the Vaal River system - is in direct competition with the demand for water to produce surplus food under irrigation. Most industrial and farming activities in Gauteng, Free State and Mpumalanga provinces, to name a few, are dependent on this water which is under threat of depletion. Given South Africa’s arid conditions, the adoption of the virtual water concept, following the Saudi Arabian experience, would be a possible conservationist measure. This article also argues that because water is limited, mining and air pollution which eventually ends up in the water should be controlled to ensure safe drinking and irrigation water.
Through Livingstone’s eyes: perspectives on water in nineteenth-century Southern Africa (1849-56)
19 January 2012
North West University

Tempelhoff, Johann W N

• Opsomming: David Livingstone (1813–1873) was deel van ‘n merkwaardige geslag ontdekkingsreisigers wat in die negentiende eeu Afrika vir die Engelssprekende wêreld oopgestel het. In Missionary travels and researches in South Africa (1858), ‘n klassieke reisbeskrywing, maak hy onder meer telkens mededelings aan mense in Brittanje en Noord-Amerika in verband met die wyse waarop hy die wateromgewing in suider-Afrika ervaar het terwyl hy op reis was in die streek. Livingstone se waarnemings werp waardevolle lig oor die wyse waarop inheemse gemeenskappe met die wateromgewing omgegaan het. Ook is daar aanduidings van die wyse waarop hulle die beskikbare waterbronne bestuur het. Ook word kennis geneem van Victoriaanse perspektiewe oor water in suider-Afrika.
Municipal engineers and local government in the Transvaal before 1910.
19 January 2012
North West University

Mäki, H

This paper examines the history of the first town engineers in the Transvaal before the Union. It will briefly examine the changes in local government in the Transvaal, focusing on municipal engineers. Examination is made of the selection processes applied in their appointments and the circumstances at the end of their tenures. It explores what was expected of municipal engineers during this period; shows what their position within the municipal structure was; and explains how vague their job description was in relation to their wide field of operation. The development of the engineer’s position in the municipal management hierarchy is interesting. He was an important figure in local government, had specific responsibilities and enjoyed specific powers. It emerges that most early town engineers had training via apprenticeship for the positions they held and that there was added pressure from elected councillors in municipalities who were prone to assiduously monitor how officials were spending public money.
Progress towards legislative transformation: a critical assessment of the 1956 and 1998 water acts regarding municipal water supply.
20 January 2012
North West University

Nealer, Eric J.;Raga, Kishore

• Opsomming: Inwoners van Suid-Afrika behoort deurlopend herinner te word dat hulle ‘n waterarmland bewoon en dat kennis oor die fisiese omgewing en die aard en omvang van effektiewe openbare bestuur van watervoorsiening van strategiese belang is. Die oppervlakte- en grondwater wat in die rivieropvanggebiede saamvloei is hidrologies en geohidrologies verbind deur die hidrologiese kringloop. Laasgenoemde manifesteer in ‘n natuurlike omgewing wat nie net gekenmerk word deur ‘n toestand van wye diversiteit en kompleksiteit nie, maar ook deur die behoefte aan goed gestruktureerde openbare dienslewering op veral die plaaslike regeringsfeer. Teen die einde van April 1994 was die voorsiening van openbare drinkwater en basiese sanitasiedienste aan al die landsinwoners op al die owerheidsfeer- en veral die plaaslike regeringsfeeragendas die hoogste in die openbare diens geskiedenis van Suid-Afrika. Gevolglik is die Regering nie net meer gemoeid met die verskaffing van genoegsame drinkwater alleen nie, maar ook met die fasilitering van die implementering van ‘n holistiese en geïntegreerde benadering aangaande die effektiewe, doeltreffende en ekonomiese bestuur van die ontwikkeling, vervoer, opgaar, behandeling en verspreiding van water. As die enigste bestuurder en bewaarder van die land se waterbronne is die Departement van Waterwese en Bosbou (DWAF) sedert veral die oorgang na ‘n demokratiese bestel in 1994 proaktief in die evaluering van bestaande beleidsdokumente sowel as die voortbring van verbeterde wette en uitvoerbare openbare beleid aangaande waterbestuursaspekte in die land. Dit is ook opmerklik dat primêre nasionale wetgewing aangaande die bestuur van openbare water sedert die 1956 - en die jongste 1998 waterwetgewing transformasie ondergaan het en dat die mees optimale voertuig tot meer effektiewe, doeltreffende en ekonomiese implementering van die nuwe getransformeerde openbare waterverwante wetgewing die 284 munisipaliteite in die land is. Dit is dan ook op hierdie regeringsfeer waar die spreekwoordelike ‘motorkarwiel die teerpad tref’ en die sukses al dan nie, van nuut geïmplementeerde openbare beleid evalueer kan word. Die fokus van die artikel is om vanuit ‘n dissiplinêr geïntegreerde perspektief die toepassing van watergewing in Suid-Afrika op munisipale owerheidsfeer krities in oënskou te neem.
Conflicting perceptions over water distribution in Sibasa-Thohoyandou area: interpreting local narratives.
23 January 2012
North West University

Wuriga, Rabson

The state perceives water as an economic commodity, even if its existing policy treats it as a national resource that should be freely accessed for basic usage. Research suggests many residents of the Sibasa-Thohoyandou area in the Limpopo Province, perceive water as a free natural resource that should not be paid for. As a result of this perception, most of the local residents are not paying for water services. In response to that, the municipality is faced with a cost-recovery problem – hence they restrict water reticulation. Residents concede that paying is a last resort because they are in need of water. Research was conducted on this issue after it surfaced as an apparent problem in the local media. The article explores and attempts to interpret the conflicting narratives on water procurement and distribution in the Sibasa-Thohoyandou area.
Bathing habits in Victorian East London.
10 February 2012
North West University

Tankard, Keith

• Opsomming: Vir die inwoners van Oos-Londen was swem nie slegs 'n sport nie, maar 'n periodieke noodsaaklikheid a.g.v. 'n tekort aan water. Vanaf 1873 het die dorpsbestuur regulasies neergelê om swemure, swemdrag, en veral aparte swemplekke vir mans en dames te bepaal. Hierdie regulasies was te konserwatief en te beperkend vir die inwoners van die kusdorp en hulle het oor 'n tydperk van etlike dekades die regulasies wetlik beveg of bloot geïgnoreer. Eers teen 1906 toe gemengde baaiery toegelaat is op voorwaarde dat mans en dames swemklere dra, is die saak besleg.
Sanitation and health conditions in Windhoek, South West Africa, under South African rule between 1915 and 1939.
05 March 2012
North West University

Kotze, C E

• Opsomming: Sanitasie in Windhoek tussen die wêreldoorloë was primitief en onbevredigend. 'n Emmerstelsel is tot 1932 in die blanke dorp gebruik, toe spoelriolering ingestel is. In die lokasie is oop slote tot 1933 gebruik, waarna kommunale spoelsloottoilette in gebruik geneem is. Ten spyte van die toestande was die dorpsmense gesond. Geen epidemies het in die tydperk as gevolg van sanitasietoestande voorgekom nie. Deur gesondheidsdienste en -geriewe is sake betreklik doeltreffend gehanteer, ten spyte van 'n tekort aan geld en opgeleide personeel. Minder sukses is egter behaal in die bestryding van geslagsiektes onder die swart bevolking.
Graaf-Reinet's water problems.
05 April 2012
North West University

Minnaar, A de V

• Opsomming: Die dorp Graaff-Reinet worstel reeds sedert sy stigting in 1786 met 'n knaende tekort aan water. In hierdie bydrae word die waternood ontleed en aandag geskenk aan onder meer die vroeëre stelsel van oop leivore en "branddamme", asook die tydperk toe waterwerke tot stand gebring is en die munisipaliteit homself bankrot moes verklaar. Deur die bou van die Van Ryneveldpas-dam is gehoop om die waterprobleme op te los. Dog periodieke droogtes het die soutgehalte van die dorp se watervoorraad uitermate verhoog, terwyl die aansprake van oewerboere langs die Sondagsrivier op hul waterregte sake vererger het. Dit het die stadsraad verplig om verskeie ander skemas van watervoorsiening te ondersoek. Hierdie pogings was egter onsuksesvol sodat Graaff-Reinet vandag steeds met die tergende Vraagstuk te kampe het.
Exploring aspects of the water history of the Potchefstroom region and the local management of it.
12 June 2012
North West University

Annandale, Elrista;Nealer, Eric J.

It is by now common knowledge that South Africa is a water scarce country and that the correct public management of its potable water sources such as the transportation of it as well as the purification of the used water is of utmost importance. In the history of South Africa, the supply of potable water and basic sanitation services to all the inhabitants has never been higher on the national, provincial and especially the local government sphere agendas than since the end of April 1994. Even though the Mooi River valley area has always been described as water rich, it might in the near future be described as “water, water everywhere, but not a drop to drink”! The city of Potchefstroom gathers its potable water from surface- and groundwater in the Mooi River Catchment. The water is collected, stored and released from the Boskop Dam from where it is transported in a 12km long open-on-top cement canal to the water purification works of the City. In an ad hoc field visit by the authors, it was discovered that the water canal is broken and being polluted in a variety of ways before it reaches the purification works. Improvement of this inefficient management situation is also currently quite impossible seeing that the Department of Water Affairs’ workforce has declined to a mere 20 people to maintain the whole of the Mooi River valley. The article starts off with a historical water related background of Potchefstroom identifying some historical happenings and developments of importance with reference to the development related to Potchefstroom and especially the source and transport of its potable water. Thereafter the article highlights some important water resources related legislation, which is obviously not being adhered to. Important role-players involved with the public management of the potable water supply for the city residents of Potchefstroom are furthermore identified. Lastly the way forward is addressed and some recommendations on the improvement of the transport of the City’s potable water through the dolomite underlain area are given.
A motivation based typology of open-water swimmers
15 January 2013
North West University

Ellis, Susanna Maria;Kruger, Martinette;Saayman, Melville

People travel to destinations for different reasons and the same applies to sporting events. To fulfil the needs of athletes and ensure that the event remains competitive, it is important to understand the needs of different markets through market segmentation. Reasons for participation (travel motives) were used to identify different market segments at the largest open-water swimming event in the world, the Midmar Mile in South Africa. The survey was conducted during the registration period in February 2010. A total of 461 questionnaires were administered and a factor analysis was conducted. Three motivational factors were identified: socialisation and escape, fun and entertainment and intrinsic achievement. ANOVAs were applied and the results showed that the swimmers did not have homogenous motives for participation. The results confirmed that motives for participating differ according to the sporting event, and that marketers and sport event organisers need to be aware that not all participants are the same. These findings can assist organisers to differentiate between the needs of different markets, and thereby adapt their marketing campaigns accordingly, which would lead to a more competitive and sustainable event.
Characterisation of the inorganic chemistry of surface waters in South Africa
04 February 2013
North West University

Huizenga, Jan Marten

The main purpose of this study was to determine a simple inorganic chemistry index that can be used for all surface waters in South Africa, in order to characterise the inorganic chemistry of surface waters. Water quality data collected up until 1999 from all sample monitoring stations (2 068 monitoring stations, 364 659 samples) in South Africa were transformed into an Excel dataset and subsequently quality screened using the stoichiometric charge balance, after which 196 570 (41%) of the water analyses could be used. Using an inorganic chemistry index (ICI) a more detailed analysis can be performed. The ICI shows that the surface water chemistry in South Africa is dominated by chemical weathering, chloride salinization and sulphate contamination. Based on the importance of these factors, primary catchment areas in South Africa can be subdivided into 3 groups, each with their own characteristic water chemistry. The results of this study allowed the development of a ternary diagram in which the 3 factors are represented. This diagram can be used to investigate the variation of the inorganic water chemistry of South African surface waters in time and space.
An efficiency analysis of basic service provision in South African local government (2006/7 to 2008/9)
07 February 2013
North West University

Van der Westhuizen, G;Dollery, B;Grant, B

The South African local government sector has undergone changes in the post-apartheid era as policy makers have sought to improve basic services provided to disadvantaged local communities. While scholars have considered various dimensions of the reform program, little effort has been directed at evaluating the effectiveness and efficiency dimensions of the changes in service provision, with some notable exceptions (van der Westhuizen and Dollery, 2009; Krugell, et al., 2010). This article seeks to contribute to this literature by evaluating the efficiency with which municipalities have provided (Reconstruction and Development Program) RDP water, RDP sanitation RDP electricity and RDP refuse removal, using Data Envelopment Analysis techniques (DEA) applied to panel data from 2006/2007 to 2008/2009 for 231 local municipalities and 46 district municipalities.
Water procurement and the environment: a comparative history of South Africa’s Nandoni and De Hoop dams 1994 - 2007.
12 February 2013
North West University

Tempelhoff, E;Tempelhoff, Johann W N

Die konstruksie van damme in Suid-Afrika het in onlangse jare uiteenlopende response tot gevolg gehad in die geledere van die omgewingsbewuste lede van die land se burgerlike samelewing. Twee voorbeelde is die De Hoop- en Nandonidam wat onderskeidelik in Mpumalanga en die Limpopoprovinsie geleë is. Hierdie damme oefen albei ‘n bepalende invloed uit op die omgewing in die wêreldbekende Nasionale Krugerwildtuin (NKW). Albei is geleë in die opvanggebied van riviere wat deur die wildtuin vloei. Hierdie damme het ‘n belangrike rol om te speel. Benewens die feit dat hulle, in sommige gevalle, in van die land se mees agtergeblewe streke voorkom, het albei grootliks ten doel om ontwikkeling te stimuleer. Die Suid-Afrikaanse regering het tans ‘n beleidsdoelwit om armoede in die land teen 2015 uit te wis. Hierdie beleid word in samewerking met die sakesektor om die doelwitte wat gestel is by wyse van samewerking te verwesentlik. Omgewingsbewustes het egter die ontwikkeling in sommige kontekste veroordeel. In die artikel word aandag gegee aan ‘n manier waarop die burgerlike samelewing, die regering en die sakesektor saamgewerk het om te onderhandel vir die voorsiening van water in streke wat waterarm is. In die besonder word aandag gegee aan die geskiedenis, sedert 1994, van die beplanning, voorbereiding en uitvoer van damkonstruksieprojekte in die Limpopoprovinsie en Mpumalanga.
Ecosystem services and international water law: towards a more effective determination and implementation of equity?
14 August 2013
North West University

Rieu-Clarke, Alistair;Spray, Christopher

Interest in an ecological- or an ecosystem-centred approach to natural resource management is not new, and in the case of water management has been very well emphasised for many decades. Recently however, a new focus has emerged around the identification and assessment of ecosystem services, and the potential to somehow use valuation of these services as a basis for more effective management of natural and human-linked systems. Despite this growing recognition, attempts to apply such an approach to transboundary watercourses are few and far between. While key principles of international water law, for example, equitable and reasonable utilisation, are not in conflict with an ecosystem services approach; significant challenges remain in its implementation. However, as the methods and tools used to identify ecosystem services improve, it is likely that such an approach will offer an important means by which to reconcile competing interests over shared watercourses in the future.
Use of satellite images to map flood extension around the city of Saint Louis in the Senegal River Estuary
15 August 2013
North West University

Dia, Aliou;Kouame, Jacob Loulou;Rudant, Jean-Paul;Wade, Soulèye

The traditional method of landsat satellite data combination and the gathering of important information made it possible to produce a Geographical Information System to monitor floods in the lower estuary of the Senegal River valley (Sandholt,I., Fog, B. & Fensholt, R., 2001). This technical approach is a powerful tool for combining important information for a better comprehension of the floods and the characterization of surface qualities on the estuary. By way of a multi-temporal approach, the study team established the qualitative and quantitative impact of floods on the various geographical objects, a detailed cartography of the land use and the surfaces flooded in 1998 and 1999. The study undertaken in Saint Louis made it possible to consider surfaces flooded in 1999, and to understand the extent of these floods compared to those of 1998. The constitution of a tool of decision-making aid makes it possible to have information relating to the extent of the flood, the scope of flooded surfaces and to detect the more exposed zones in order to establish a hierarchical map according to the percentage of exposure to the risk of the geographical objects affected by the floods (populations), road infrastructures and tracks, medical and social infrastructures and perimeters of cultures (agriculture).
Resettlement of communities - The case study of Jaguaribara: a resilient community (Northeast of Brazil)
15 August 2013
North West University

Amorim, Isabelle

This paper examines the displacement of the inhabitants of Jaguaribara (Northeast Brazil) who were resettled due to the construction of the “Castanhao”. #e Government planned a new city to shelter the inhabitants from “Old Jaguaribara” that was $ooded due to the over$owing of the dam. #e case of Jaguaribara provides another perspective for analysing the consequences of the resettlement of the community, elucidating - besides the impoverishment risks - the protective factors that came up during the process of resistance against the construction of the dam, in the light of the concept of resilience. In order to capture the various dimensions of this process, qualitative primary data were used as the main source, together with documentation made by NGOs and professionals involved during the process of resistance against the construction of the dam, as well as semi-structured interviews. #e enhancement of resilience in Jaguaribara represented the possibility to transform isolated individuals into a powerful integrated group that could combine forces, catalyse collective gains as well as articulate and defend common interests.
The silent victims of humanitarian crises and livelihood (in)security: a case study among migrants in two Chadian towns
16 August 2013
North West University

Djindil, Syntyche Nakar;De Bruijn, Mirjam

Once a humanitarian disaster receives coverage in the global media, the international community usually mobilises to reduce the most severe consequences. However people in Chad are experiencing endemic crises that are detached from speci!c triggers, and they are not receiving any international assistance to help relieve the hardships they face. "is study involves 111 migrant households from central Chad that, as a result of war and drought, have lost everything and now have to live in squatter areas of N’Djamena and Mongo, facing uncertainty and threats while negotiating their livelihoods. Qualitative and quantitative methods have been combined in this study to reveal the intriguing story of their daily lives in the face of complex and endemic crises. Anthropometric and health data were generated to determine the nutritional status of mothers and their children under !ve. Life histories, in-depth interviews and participatory observation allowed the researchers to capture the negotiation strategies they use to access food and shelter, their experiences of food insecurity and sanitary vulnerability, and the consequences these have on daily life. Results indicate that 62% of households were female headed, there were high rates of acute (40-50%) and chronic (35-40%) malnutrition and 46% of the mothers were underweight and anaemic. Infant mortality rates were also high at 30%-42% and 97% of the children had had incomplete or no vaccinations. No households had access to clean water, sanitation or public-health services. Endemic corruption and abuse by the authorities were identi!ed as major sources of day-to-day insecurity. Theese migrants were not expecting any improvement in their livelihoods in the foreseeable future and saw these miserable conditions as normal.
Together we can do more – environmental consciousness in the South African dam construction sector (1945-1980)
03 September 2013
North West University

Van Vuuren, Lani

For several thousand years societies have diverted and dammed up rivers to meet their increasing water needs. The Industrial Revolution ushered in the modern era of water resource development, which has led to the construction of an estimated 50 000 large dams worldwide. Rising concerns over the state of natural resources following the Second World War resulted in the emergence of public anti-dam lobby groups who used protest and advocacy to place pressure on authorities to cease dam construction activities and improve environmental legislation. While these actions proved successful in many countries this approach has led to conflict between environmental groups and dam authorities. South Africa is highly dependent on dams for stable and regular water supply. The country’s 320 largest dams together store some 66% of the country’s mean annual runoff. In contrast with the global environmental movement, institutionalisation of the environment occurred within the water engineering sector not as a result of outside pressures but due to rising concerns from water engineers themselves. In the absence of strong adversarial environmental non-governmental organisations, improved management of the impact of large dams grew out of early cooperation between department officials and aquatic scientists, especially around the sustainable management of water resources in KwaZulu-Natal, as this article illustrates. This trend towards negotiation and collaboration led to the country’s main developer of large dams, the Department of Water Affairs, instituting voluntary environmental policies from 1980.
Comparative behavioural assessment of an established and a new tigerfish Hydrocynus vittatus population in two man–made lakes in the Limpopo River catchment, Southern Africa
16 October 2013
North West University

Smit, N.J.;O'Brien, G.C.;Bulfin, J.B.;Husted, A.

With the continued establishment of man-made lakes within the natural distribution range of tigerfish in southern Africa, many artificial tigerfish populations now exist in the region. Very little of the behavioural ecology of these artificial but ecologically important populations is known. Letsibogo and Schroda man-made lakes are two such systems in the Limpopo River catchment. Currently, an established population of tigerfish occurs in Schroda, which is proposed to be used to establish another population in Letsibogo. This study evaluates the suitability of Letsibogo for tigerfish and the behavioural ecology implications associated with an artificial population in the lake. The behaviour of a small population of tigerfish relocated from Schroda to Letsibogo was monitored and compared with the behaviour of the established Schroda population. In Letsibogo the tigerfish established behavioural patterns suggesting that it is suitable to maintain a tigerfish population. To conserve the locally threatened tigerfish in the Limpopo catchment, the establishment of populations in man-made lakes such as Letsibogo is recommended. The effect of tigerfish on indigenous fishes in Letsibogo is unknown and should be considered.
Banking customers’ attitudes toward complaining: their likelihood of voicing a complaint and service recovery they consider appropriate
17 October 2013
North West University

Mostert, Pieter Gerhardus;Petzer, Daniel Johannes

This paper measures the attitude of banking customers towards complaining and their likelihood to complain when a service failure is experienced at their current and another bank. Insight is also provided into the service recovery responses customers consider appropriate when a service failure is experienced. The target population included individuals in the Gauteng Province of South Africa who hold a bank account in their personal capacity. An interviewer-administered survey was used to collect data using non-probability quota sampling based upon population group and gender. A demographic profile of respondents, as well as the findings in terms of the aforementioned constructs and related hypotheses is provided. The study found that respondents have a positive attitude towards complaining, and that they are significantly more likely to voice a complaint when experiencing a service failure at their current bank than at another bank. Significant differences also exist with regard to the individual responses respondents consider appropriate when confronted with a hypothetical service failure experienced at their current bank and another bank.
Case study: energy savings for a deep-mine water reticulation system
31 October 2013
North West University

Vosloo, Jan;Liebenberg, Leon;Velleman, Douglas

In deep level mining, water reticulation systems are one of the major consumers of electricity. The refrigeration plants, together with the underground water supply and dewatering systems are integrated to form one complete water reticulation system. This integrated water reticulation system extracts hot water from the mine, cools it down and returns the cold water to the various underground mining levels. As much as 42% of the total energy consumption on a typical deep level gold mine can be ascribed to the water reticulation system. Reducing the overall water demand and therefore electricity costs will depend on climatic conditions, operating strategy, water reservoir capacity, and electricity tariff rates. In this paper, a method is presented to determine the optimum water reticulation strategy for different electricity tariffs. This model minimises the total operating cost of the water reticulation system by a trade-off between the cost involved in providing effective pump control and the savings achieved under a specified electricity tariff. A case study of a typical deep mining operation shows that a reduction of 65% during peak demand and 2% overall electricity reduction is possible by adopting this new control strategy. The corresponding savings in operating cost is 13%. Techniques were developed to integrate, simulate, optimise and control all components of the water reticulation system. This will allow for a quick assessment of the effect of individual components on the complete system. By integrating all these components into a single system, the operation of each component can be assessed and optimally controlled without adversely affecting other operations of the system.
Perceptions of water access in the context of climate change by rural households in the Seke and Murewa districts, Zimbabwe
26 November 2013
North West University

Mudombi, Shakespear;Muchie, Mammo

The objective of the study was to assess perceptions of rural household heads with regard to various aspects of water access and climate change, and to evaluate whether there were significant differences in perceptions of respondents from female-headed and male-headed households. The study is based on a cross-sectional survey of 300 respondents conducted in the Seke and Murewa districts of Zimbabwe in 2011. The analysis included mainly descriptive statistics. The majority of both female-headed and male-headed households relied on rainfall for their crops, rivers were cited as the main water source for their livestock and protected wells supplied water for household use. Households experienced water shortages, which were attributed mainly to reduced rainfall. The general perception was that there would be less water available in future, with a greater proportion of female-headed than male-headed households perceiving such difficulties. However, very few respondents indicated that they would consider emigrating, although female-headed households were more likely to consider emigrating than male-headed households. A considerable number of respondents indicated that they did not have any means to overcome the water shortages. This highlights the need for interventions such as training and empowerment of individuals with regard to sustainable water use and management.
How Pat Metheny came to Carolina in Mpumalanga, South Africa: using music in transdisciplinary water research
29 January 2014
North West University

Tempelhoff, Johann W N

Listening to music can help researchers to comprehend and gain insight into complex problems in transdisciplinary research. This article explains how members of a research group at North-West University in South Africa conducted research on a crisis in the urban settlement of Carolina in Mpumalanga Province when acid mine drainage (AMD) from local coal mining operations was found in the municipal water supply. In grappling with complex issues such as the failure of communication with local stakeholders, the group resorted to using the music of Pat Metheny’s music to come to a better understanding of the crisis.
A comparison of the traditional and simplified methods for water poverty index calculation
15 September 2014
North West University

Van der Vyver, Charles

The aim of this research is to quantify the difference in the water poverty index when calculated with the traditional method, compared to the new and simplified water poverty indices. It is calculated and compared for the three towns that together form the Vaal Triangle region in South Africa. A case study is performed with data that was collected at the household level, all of which is at a high assurance level. Although many functions are available for the calculation of composite indices, the study finds that although the simplified index produced the lowest overall values, the final recommendation regarding which town is most in need of an intervention would have been unchanged. It concludes that the scale at which the data is gathered, the chosen components, and the data sources could all influence these results, and that the method comparisons are critical in ensuring the relevance of the chosen method. Future research should focus on refining the available methods, as well as on documenting the best methods for different scenarios.
Attitudes towards environmental issues: a case of Bophelong Township
08 October 2014
North West University

Maloma, Ismael;Sekatane, Mmapula Brendah

This paper examines the attitudes that the households of Bophelong Township have towards environmental issues in their area. Focus was placed on issues pertaining to air pollution and littering in the Township. The study investigated the attitudes of households as to the causes of pollution and littering in their area. Emphasis was also placed on their attitudes as to who should take the initiative and responsibility for the abatement of the pollution and the cleaning of the area. The results highlight the factors that should be considered when looking at household attitude towards pollution in a South African Township.
Challenges and solutions for Local Economic Development (LED) municipal institutional arrangements. The case of the Northern Free State
17 October 2014
North West University

Meyer, D.F.;Venter, A.

Appropriate municipal institutional structures and arrangements are important for successful local economic development (LED), policy development and implementation. The purpose of this article is to analyse the status quo of the municipal institutional arrangements in the local government sphere. While community involvement is critical, changes are required at the institutional level to ensure effective LED. Successful implementation of development strategies and interventions requires appropriate institutional arrangements in the local sphere. Since 1994, local government in South Africa has been tasked to fulfil a developmental role, which places significant pressure on institutional capacities. Due to a lack of capacity, skills, funding and appropriate policies, local government has achieved limited success with its developmental mandate. The Northern Free State region (also known as Fezile Dabi District Municipality) has been selected as the case study region to test the institutional arrangements for LED at the five municipalities (one district municipality and four local municipalities) within the region. The analysis highlights the effect of the lack of institutional arrangements for LED at the municipal level, and that LED is as yet not well embedded in municipal practice. Furthermore, this article seeks to identify possible solutions for LED with specific reference to municipal institutional arrangements. Although this article does not claim to give definitive solutions to the problem which could cause municipalities to fail in delivering on their developmental mandate, it nevertheless serves as a starting point for seeking sustainable solutions for LED institutional arrangements. It should be noted that the physical and socio-economic conditions of a specific locality have an impact on the preferred LED institutional arrangements. This article also provides solutions to foster local development optimally, such as dynamic local leadership, effective partnership formation, skills training and an integrated approach to LED
Rethinking domestic water resource management: a shift from gender–biased to gender–based approach
19 November 2014
North West University

Vyas-Doorgapersad, S.

Historically, socially and economically, women in many societies have been given the onerous responsibility of travelling long distances, often in unfavourable weather conditions, to carry home containers of water on their heads for drinking and domestic purposes. Women are over-represented in performing these tasks but are under-represented in offering a significant contribution in water management at decision-making levels. This article aims to explore and analyse the definitive transferral of gender responsibility from ‘carrying’ water to ‘carrying responsibility’ for water. The article [qualitative] builds on a literature review, policy regulations and case-studies that reflect transformational reallocation of set tasks and explores the way forward to utilise water as a means of enhancing gender empowerment. The article recommends the use of gender disaggregated data and a close consideration of gender-based and gender-sensitive approaches in defining water policies. Importantly, scope is also left for further investigation of strategies and policies which promote gender empowerment in and through water programmes. The article emphasises the roles of women in water resource management in South Africa as a case study.

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