Wetlands are an important part of the landscape as hydrogeomorphological ecosystems. Over the centuries their importance has not received relevant attention; instead they have been treated as wastelands impeding development for maximum economic benefits. Research evidence from different parts of the world has influenced the change of such negative perceptions to an extent that the issue of wetlands' rehabilitation/restoration, conservation and management is firmly on the global agenda and local agendas of various countries, as evidenced by the adoption of the Ramsar Convention in 1971, and the Working for Water and Working for Wetlands programmes of the South African government. The aim of this research was to investigate the hydrological and geomorphological functions of a headwater wetland located in the Featherstone Kloof Catchment near Grahamstown, South Africa. The research was based on the hypotheses that wetlands store sediments, attenuate floods, store water and prolong downstream flows. A literature survey was conducted to gauge the state of knowledge about wetlands, particularly their hydrogeomorphology. An attempt was made to locate the study area within the broad historical and spatial context using a number of methods, including the radiocarbon dating of wetland sediments, the review of relevant literature and the analysis of historical hydroclimatic data. The results revealed that the wetland has existed for approximately 2000 years - as the oldest radiocarbon date obtained was 1850±50 BP. An analysis of more than a century (+120 years) long Grahamstown rainfall series indicated a steady fluctuation of rainfall around the mean, with regular decada1 cycles of wet and dry spells. Years with more rain below average were more common than those with higher rainfall, and storms events were quite common in the III area over the period. The distribution of seasons in the area over a calendar year period was demonstrated through the use of evaporation data. An intensive monitoring of hydrological and geomorphological variables was carried out using a combination of methods. The topography of the instrumented site was determined using a Total Station from reference benchmarks. Hydrological measurements included a nest of forty-eight piezometers for water table monitoring, and streamflow gauges at the upstream and downstream limits of the study site. Soil stratigraphic analysis was carried out through field techniques and laboratory measurements. A survey of wetland sediments was carried out after the main floods events. Data generated were used to analyse relationships between various variables and their role on the functioning of the wetland. The water balance of the wetland was quantified. The results indicated that the wetland was able to perform the cited hydrogeomorphological functions to some extent. For example, one of the key findings of this research is that the wetland was important in sustaining base flows under normal circumstances. However, the wetland did little to attenuate large floods. The results also revealed some important questions that require further research, including the role played by extreme flood events in altering wetland characteristics, the contribution of each water balance component in the hydrological functioning of wetlands, and importance of quantifying sediment budgets of headwater wetlands. The study demonstrated the complex nature of the wetland hydro geomorphology and that certain questions about wetlands require direct field monitoring to be better understood. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in

Despite the fact that wetlands have been understood to be important for a wide range of ecosystem services, wetlands continue to be degraded globally. There has been a growing need to develop biomonitoring tools that reflect the present ecological state of wetlands, but very few attempts have been made in South Africa to achieve this, and those that have attempted this have generally achieved limited success. This study was conducted to develop and test the congruency of four selected biological indicators (dragonflies, frogs, macroinveterbrates and plants) in relation to the assessment of present ecological state using an existing method in South Africa, "WET-Health". WET-Health assessments rely primarily on transformations to a wetland that result from human impacts in both the catchment and the wetland itself. Using the tool, a health score is obtained that is consistent with the Department of Water Affairs (DWA) current "present ecological state” as applied to river health assessment. The study was conducted in agricultural settings of the Midlands of KwaZulu-Natal based on 13 wetlands. The selected wetlands were scored using WET - Health and grouped in four different ecological condition classes (A, B, C and D). Physical characteristics (wetland area, mean depth), biological characteristics (species cover/abundance, presence and species richness), and chemical characteristics (ammonia, pH, sulphate, nitrogen and phosphate) were also recorded in the selected wetlands. Nineteen different species of dragonfly were recorded in this study. The study demonstrated that dragonflies are a promising bioindicator of wetland present ecological state as the dragonfly index was found to be closely correlated with WET- Health scores. Open water bodies within the selected wetlands were the focus of dragonfly sampling, as male dragonflies are territorial and they will patrol or be found around this habitat. Emergent vegetation dominated by sedges formed the focus of macroinvertebrate sampling in this study because greater numbers of macroinvertebrate families were found in this biotope in comparison to open water areas with no emergent vegetation. A total of 47 macroinvertebrate families were recorded in this study, but SASS5 scores based on macroinvetebrates showed no correlation with WET-Health scores. A total of 10 different frog species were recorded in this study. All the species were common frog species found in most parts of the country. Frog species richness and occurrence showed no correlation with WET- Health scores. A total of twenty samples of two meter radius were measured per wetland and sampled for plant species and estimation of cover-abundance of each species per sample. Over 50 different plant species were recorded in this study, and both species accumulation and species richness showed a degree of correlation with WET-Health scores. All the wetlands in class A had generally higher species accumulation rate and species richness compared to the other wetland classes. In addition to testing the congruency of four selected biological indicators with WET- Health, water quality was measured in all the wetlands. Wetlands in class A were associated with improved water quality as the water passes through the wetland. However, wetlands in class C and D did not show consistently improved water quality between the apex and the toe of these wetlands. In some cases the water quality deteriorated as it passed through wetlands in these two classes.

Thesis (MA)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: The Table Mountain Group (TMG) Aquifer System is a regional fractured aquifer system with a large potential as a source of future water supplies in the Western and Eastern Cape. This system is currently under consideration for large-scale water abstraction. Many terrestrial ecosystems, however, are dependent on these groundwater resources for survival. Exploitation of ground water resources at a rate exceeding the rate of natural recharge would result in a lowering of the water table and the drying up of seeps. The main objective of this study was to determine if satellite remote sensing data can be used for the detection of groundwater-dependent wetlands, and secondly, to use multi-temporal imagery for estimating seasonal changes experienced in wetland communities in relation to surrounding vegetation. The Kogelberg Biosphere Reserve, situated approximately 30km to the east of Cape Point in the Western Cape, South Africa, was selected for investigation. To accomplish the objectives, three Landsat 7 ETM+ images (path/row: 175/84) captured on 22 September 2001, 18 May 2002 and 23 September 2002 were acquired. Image fusion of the multispectral bands (30m resolution) with the panchromatic band (15m resolution) provided 15m multispectral images for analysis purposes. Geometric correction, radiometric normalisation and atmospheric corrections was performed in order to ensure pixel-level comparability between images. Once comparability between images was guaranteed, vegetation indices and tasselled cap components were derived to provide threshold values of moisture stress indicators and productivity estimations of wetland communities in relation to surrounding non-wetland communities. Additionally, change vector analysis on these transformations provided the ability to detect and assess the seasonal changes experienced by these communities during an annual cycle. The results of these transformations were combined in a rule-based image classifier in order to assist in estimating the seasonal dependency of observed wetland communities. The ability to use Landsat 7 images and the abovementioned image processing procedures to identify wetland communities with a high probability of groundwater interaction was demonstrated with a high degree of accuracy (78%). It is recommended that future studies concentrate on increasing classification accuracies, while focusing on incorporating these techniques into a remote monitoring system for assessing the impacts of groundwater extraction on the groundwater-dependent wetland communities. / AFRIKAANSE OPSOMMING: Die Tafelberg Groep (TBG) Akwifer is 'n regionale verskuiwingsakwifer sisteem met groot potensiaal as toekomstige waterbron vir die Wes- en Oos-Kaap. Grootskaalse grondwateronttrekking uit hierdie sisteem word tans ondersoek. Baie terrestriële ekosisteme is egter vir oorlewing van grondwaterbronne afhanklik. Grondwaterontginning teen 'n tempo hoër as die natuurlike aanvultempo sal die watertafel laat daal en syfersones laat opdroog. Die hoofdoel van die studie was om te bepaal of satellietbeelde gebruik kan word om grondwater-afhanklike vleilande waar te neem, en om 'n tydsreeks van beelde te gebruik om die seisoenale verandering in vleilandgemeenskappe relatief tot omliggende plantegroei te raam. Die Kogelberg Biosfeer Reservaat, ongeveer 30km oos van Kaappunt, is as studiegebied geïdentifiseer. Drie Landsat 7 beelde (baan/ry: 175/84) van 22 September 2001, 18 Mei 2002 en 23 September 2002 is ontleed. Die Landsat 7 multispektrale bande (30m resolusie) is met behulp van beeld-fusietegnieke met die panchromatiese band (15m resolusie) gekombineer om multispektrale beelde te lewer met 15m grondresolusie. Geometriese korreksie, radiometriese normalisering en atmosferiese korreksie is op elk van die beelde toegepas om beeld-selvlak vergelykings tussen beelde 'n moontlikheid te maak. Met beeldvergelykbaarheid verseker, is plantegroei-indekse en 'tassled cap' transformasies gebruik om afsnywaardes vir vleiland-identifikasie te bereken. Verder is veranderingsvektoranalises op die transformasies bereken om die seisoenale veranderinge oor die jaarsiklus in vleilande te bepaal. Die resultate hiervan is vervat in 'n reël-gebaseerde beeldklassifiseerder waarmee vleilande se seisoenale grondwater afhanklikheid geraam is. Die vermoë om vleilande met 'n hol! waarskynlikheid van grondwater interaksie uit Landsat 7 beelde te identifiseer is met 'n hol! vlak van totale akkuraatheid (78%) gedemonstreer. Die aanbeveling is dat toekomstige studies moet fokus op die verhoging van hierdie klassifikasie akkuraathede. Die tegnieke moet toegespits word op die ontwikkeling van 'n afstandswaarnemingstelsel om die

South Africa is ranked as one of the most mega-biodiverse countries in the world. But as the country faces poverty, unemployment and income inequalities, it is a mammoth task to develop, sustainably use and appreciate this natural capital. Thus, South Africa must find ways to ensure a balance between conservation of biodiversity and the achievement of socio- economic development. But when land is set aside for conservation, in most cases, local communities are on the receiving end of the decision making, with little to no opportunity to be involved. The Colbyn Valley Wetland is different, however. The site provides invaluable ecosystem goods and services to the local residents, as well as being an integral part of the Hartbeesspruit catchment and Roodeplaat dam. It has a history of sustained attempts to convert the site into housing estates, shopping centres or car parking. These attempts have met with unrelenting resistance by the local residents. Contrary to the experiences of other communities in South Africa, Colbyn Valley residents have elected to work together with other stakeholders to ensure the protection of this site. This study documents the processes that the residents undertook to protect the wetland. In this regard, local authorities can learn how to leverage stakeholder engagement to protect other sites. Importantly, the study found that the various stakeholders involved in the preservation of the Colbyn Valley Wetland were driven by different but interwoven interests. Thus, different interests need to be taken into consideration before protected areas adjacent to communities can be proclaimed. For example, the primary stakeholders - local residents who initiated the call to protect the Colbyn Valley Wetland – hold strong beliefs that the wetland must be preserved for ecosystem goods and services that it provides. Secondary stakeholders – the provincial government departments responsible for the management and protection of ecosystems – only acted when pressured by the local residents, despite their legal obligations to protect the site (as it carries so much value to the water provision of the city). The tertiary stakeholders – various voluntary institutions and people – elected to support the conservation effort due to the manner in which the local residents organised themselves and developed a vision for the site. / Environmental Sciences / M. Sc. (Environmental Science)

This study examined the current plant diversity status and the impact of drivers of change on the peat basins of the Kromme River peatland. It was conducted at six sites over sixty one years in the Eastern Cape Province of South Africa. I reviewed the rapid habitat and biodiversity loss of wetlands globally and discussed the distribution of wetlands and specifically peatlands in South Africa. Plant species diversity was assessed using Modified- Whittaker plots. The influence of environmental variables on floristic composition and distribution was investigated using ordination techniques (DCA and CCA). Land use dynamics were assessed by applying GIS techniques on orthorectified aerial images. Six different peat basins were subjectively classified into good, medium and poor condition peat basins. The good condition peat basin (Krugersland) was the most diverse in plant species (4.1 Shannon-Weiner’s index) (p> 0.20; F = 11.04; df = 2), with the highest mean number of plant species (32.5 ± 3.4). This was followed by the medium condition class (Kammiesbos) (26.5 ± 9.0) and poor condition class (Companjesdrift) (22.5 ± 8.9). On average, species composition was not evenly distributed across the peat basins (p> 0.21; F = 0.94; df = 2), since 77.8% of the Shannon-Weiner evenness index obtained were less than one. However, there were variations in plant species richness across six peat basins as confirmed by Oneway ANOVA test (p= 0.0008, F = 1241.6, df = 4). Key environmental variables that influenced plant species distribution and structure were erosion and grazing intensity, potassium, phosphorus, soil pH and calcium. Total species variance accounted for in the first two axes for ground cover and plant height were 40.7% and 56.4% respectively. Alien species (e.g. Acacia mearnsii and Conyza scabrida) were common in degraded peat basins, whereas good condition peat basins supported indigenous species (e.g., Cyperus denudatus, Chrysanthemoides monolifera and Digitaria eriantha). Analysis of aerial images revealed a general progressive decrease in the peatland area between 1942 and 1969 in the good (Krugersland) and poor (Companjesdrift) condition class, with a marginal increase from 1969 to 2003. Peatland area in the good and poor condition class decreased by 5.3% and 8.3% respectively between 1942 and 1969, with a marginal increase of 1.5% and 4.1% respectively from 1969 to 2003. Annual net rate of change in peatland area over the 61 year period was -0.32% (good condition class) and - 0.79% (poor condition class). Transformed lands were impacted by drivers of change such as alien invasives, agricultural activities, erosion and sediment transport. The area under alien invasives increased by 50% between 1942 and 2003, with an annual net rate of change of +0.82 (good condition class) and +1.63% (poor condition class).

The study focused on the role of the local community in the management of wetland. The study was triggered by the lack of participation of the local community in the management of the wetland. It is important to note that wetlands perform a number of ecosystem services, some of which are well recognised, others less so, and are internationally recognised as being one of the most important ecosystems for the conservation of biodiversity. South Africa is a signatory to the international obligations, which makes it a legal responsibility to make sure that wetlands are managed appropriately. It is therefore important for these natural resources to be managed appropriately. Information for generating data was obtained through the assessment of the wetland health and from the investigation of the management of the local community. In order to achieve the objectives of the study, qualitative method was used to gather the necessary data. The findings indicate that the current state of the wetland is severely modified, which means large loss of natural habitat, biota and basic ecosystem functions has occurred. The results also indicate that the community is ill-equipped to manage the resource appropriately. The findings therefore imply that immediate management interventions must be developed to improve the health of the wetland. In improving the state of the wetland, the study recommends, amongst others, that mitigation measures aimed at improving the wetland health and participation of wetland users be promoted. An establishment of a community-driven and multi-stakeholder intervention mechanism to help the community manage and utilise the wetland properly is also recommended. The study concludes by indicating that the community must comply with the environmental legislation and takes a lead in the management of the wetland, for the aim of restoring the functionality and integrity of the wetland. / Environmental Sciences / M. Sc. (Environmental Management)

The study focused on the role of the local community in the management of wetland. The study was triggered by the lack of participation of the local community in the management of the wetland. It is important to note that wetlands perform a number of ecosystem services, some of which are well recognised, others less so, and are internationally recognised as being one of the most important ecosystems for the conservation of biodiversity. South Africa is a signatory to the international obligations, which makes it a legal responsibility to make sure that wetlands are managed appropriately. It is therefore important for these natural resources to be managed appropriately. Information for generating data was obtained through the assessment of the wetland health and from the investigation of the management of the local community. In order to achieve the objectives of the study, qualitative method was used to gather the necessary data. The findings indicate that the current state of the wetland is severely modified, which means large loss of natural habitat, biota and basic ecosystem functions has occurred. The results also indicate that the community is ill-equipped to manage the resource appropriately. The findings therefore imply that immediate management interventions must be developed to improve the health of the wetland. In improving the state of the wetland, the study recommends, amongst others, that mitigation measures aimed at improving the wetland health and participation of wetland users be promoted. An establishment of a community-driven and multi-stakeholder intervention mechanism to help the community manage and utilise the wetland properly is also recommended. The study concludes by indicating that the community must comply with the environmental legislation and takes a lead in the management of the wetland, for the aim of restoring the functionality and integrity of the wetland. / Environmental Sciences / M. Sc. (Environmental Management)