A research report submitted to the Faculty of Science in partial fulfilment of the requirements for the degree of Master of Science. Johannesburg, 31 August 2012. / Unable to load abstract.

Bibliography: pages 162-177. / The seasonal and diurnal patterns of photosynthetic gas exchange and the water relations of seven species of the mediterranean-climate region of South Africa (fynbos) were investigated. The following species, representing the major fynbos elements, were chosen for intensive investigation: Erica plukenetii and Erica hispidula (ericoid element), Thamnochortus lucens and Askidiosperma paniculatum (restioid element), Protea laurifolia and Leucadendron salignum (proteoid element). Metrosideros angustifolia, a shrub of riparian habitats, was also studied.

Vegetation degradation in South Africa has been identified as a serious environmental problem, especially impacting communal areas. This study investigated the spatial distribution of vegetative condition, along with related changes, deterioration and trends, across the communal villages of the central Keiskamma catchment, Eastern Cape Province. The principal hypothesis of this study was that differences in grazing management strategies may explain the variations in vegetation condition within these communal areas. This investigation assessed the status and condition of vegetation in relation to local institutional grazing management systems, in association with factoring in relevant topographical and physical elements. Topographic homogeneity of the study area was tested by extracting topographic parameters from a DEM and performing a Chi squared test. Remote sensing techniques were used to analyse the spatial and temporal variations in vegetation condition between the villages. Landsat TM images, from 1984 and 1999, in conjunction with SPOT imagery of 2011, were used to assess the spatial trends in vegetation. Land use and cover maps were generated, comprising five categories of land cover, viz. intact vegetation; transformed vegetation; degraded vegetation; bare surfaces; and water. The classification of the images was achieved using the supervised object-oriented classification techniques, which aggregates pixels of each class into homogeneous objects. Information regarding existence and functionality of local institutional structures was obtained through structured interview method. Vegetation condition was correlated to grazing management systems, with the logistic regression confirming a significant relationship between vegetation condition and grazing management systems. Analysis of vegetation condition trends revealed a decline in pristine vegetation with an increase in degraded vegetation and exposed soil throughout the villages. However, it was observed that the decrease in pristine vegetation, with the associated increase in degraded vegetation and soil, do not occur evenly among the villages of the central Keiskamma catchment; the communal areas surrounding certain villages exhibited severe degradation of soil and vegetation, while other villages demonstrated less or minimal deterioration in their environs. The topographic homogeneity of the study locale lent credence to the theory that the uneven distribution of vegetation conditions between the villages is not controlled by topographic factors. Analysis of the data, collected through interviews, revealed differences in the functionality of institutional structures between villages. A statistically significant correlation between the vegetative condition and implementation of grazing management systems, supports the postulated concept that the variances in vegetation condition of the central Keiskamma catchment reflect the efficacy or inefficiency of the settlements‘ grazing management systems. Through gathering, analysing and assessing all the data, a conclusion was drawn, which advances that the primary requirement for remedial action in reversing the current decline in vegetation condition is strengthening the local institutional management regimes throughout all villages under study.

Text in Afrikaans, abstract in Afrikaans and English / Lineere plantegroeipatrone bestaande uit afwisselende grasryke mikrotrog- en boomryke- kruinbane wat parallel met die helling georienteer is, kom voor op die voetbang van die Baviaansberg, in die Warmbadgebied, Noordelike Provinsie. Die hoofdoelwitte van die studie was om uit 'n landskapekologiese benadering die verskynsel te probeer verklaar, om die vertikale en horisontale variasie van eienskappe te kwantifiseer en om die impak van die mens daarop te benadruk. Die differensiasie in die Tukulu- en Etoshagrondvorms in onderskeidelik mikrotroe en -kruine is die gevolg van grondprosesse soos illuviasie van klei, loging en ferrolise.Granulometriese analise dui daarop dat die moedermateriaal van gronde van een bron afkomstig is. Kolluviasie en afsetting van moedermateriaal op die voethang was waarskynlik die beginpunt van landskapontwikkeling waar verdeelde oppervlakvloei van water oenskynlik die mikrostrukture geinisieer het. Na aanleiding hiervan het die ontwikkeling van grondverskille en waterregimeverskille tot plantegroeiverskille gelei. Faktore wat die patroon geaksentueer het is termietaktiwiteite, brand en beweiding. / A linear vegetation pattern consists of alternating grassland micro troughs and woody micro crests lanes which were orientated parallel to the slope occurred on the foot slope of the Baviaansberg, in the Warmbaths area, Northern Province. From a landscape ecological approach the principal aims of the study was to explain the phenomenon, to quantify the vertical and horizontal variation of features and to accent the impact of man on it. The differentiation in Tukulu and Etosha forms in micro troughs and micro crests respectively were the effect of several soil processes. Granulometric analyses showed that the parent material of soil was derived from one source. Colluviation and deposit of parent material was probably the starting-point of landscape development where the divided surface flow of water apparently initiated the micro structures. As a result of this the development of soil and water regime differences lead to vegetation differences. / Geography / M. Sc. (Geografie)

A two-year analysis of pollen rain was conducted in the Pretoria-Witwatersrand-Vereeniging district of the Transvaal, South Africa. Poaceae WaS the major component of the pollen assemblage, comprising 52% regionally. Of the total pollen count, 58.8% was non-seasonal and present throughout the year. During the analysis it became apparent that fungal spores dominated the atmospheric content, accounting for 94% of total airspora, considered here to incl ude pollen and fUngal spores.[Abbreviated Abstract. Open document to view full version]. / AC2017

Text in Afrikaans, abstract in Afrikaans and English / Lineere plantegroeipatrone bestaande uit afwisselende grasryke mikrotrog- en boomryke- kruinbane wat parallel met die helling georienteer is, kom voor op die voetbang van die Baviaansberg, in die Warmbadgebied, Noordelike Provinsie. Die hoofdoelwitte van die studie was om uit 'n landskapekologiese benadering die verskynsel te probeer verklaar, om die vertikale en horisontale variasie van eienskappe te kwantifiseer en om die impak van die mens daarop te benadruk. Die differensiasie in die Tukulu- en Etoshagrondvorms in onderskeidelik mikrotroe en -kruine is die gevolg van grondprosesse soos illuviasie van klei, loging en ferrolise.Granulometriese analise dui daarop dat die moedermateriaal van gronde van een bron afkomstig is. Kolluviasie en afsetting van moedermateriaal op die voethang was waarskynlik die beginpunt van landskapontwikkeling waar verdeelde oppervlakvloei van water oenskynlik die mikrostrukture geinisieer het. Na aanleiding hiervan het die ontwikkeling van grondverskille en waterregimeverskille tot plantegroeiverskille gelei. Faktore wat die patroon geaksentueer het is termietaktiwiteite, brand en beweiding. / A linear vegetation pattern consists of alternating grassland micro troughs and woody micro crests lanes which were orientated parallel to the slope occurred on the foot slope of the Baviaansberg, in the Warmbaths area, Northern Province. From a landscape ecological approach the principal aims of the study was to explain the phenomenon, to quantify the vertical and horizontal variation of features and to accent the impact of man on it. The differentiation in Tukulu and Etosha forms in micro troughs and micro crests respectively were the effect of several soil processes. Granulometric analyses showed that the parent material of soil was derived from one source. Colluviation and deposit of parent material was probably the starting-point of landscape development where the divided surface flow of water apparently initiated the micro structures. As a result of this the development of soil and water regime differences lead to vegetation differences. / Geography / M. Sc. (Geografie)

Desertification is the diminution or destruction of the biological potential of land, and can lead ultimately to desert-like conditions. The vegetation of southern Africa is claimed to have altered over the past 100 years and much of the change is attributed to pastoral practice. In recent years however there has been much debate around the issue of the deterioration and loss of productivity of the natural rangelands, specifically those under communal management. It is one thing to claim that the vegetation has changed but quite another to produce data and analyses to show this unequivocally. Furthermore it is generally difficult to determine the nature and extent of change in natural ecosystems, as one does not know what the optimal base-line conditions should be. For this reason emphasis has been placed on developing models of potential or expected vegetation. By comparing a model of potential or expected vegetation with that of the contemporary vegetation, areas that deviate from expectation can be identified, in so doing providing evidence of the direction of change in the rangelands under various management treatments. The objective of this study was to determine shifts in the vegetation under different land-use treatments, by developing a technique to predict the potential vegetation of an area. In order to explore the nature and extent of degradation at the landscape scale a study site was selected where a range of land-use and rangeland management practices could be studied in parallel. The mid-Fish River valley consists of three markedly different units of land management, namely commercial rangelands, communal rangelands and nature conservation areas. The vegetation within the mid-Fish River valley falls within the Thicket biome and consists of three main vegetation types namely, Short Succulent Thicket, Medium Succulent Thicket and Mesic Bushclump Savanna. The creation of this potential vegetation model was dependent on the direct gradient analysis approach of relating the community patterns with environmental variables. To achieve this, floristic information was collected at sites along a topographical-moisture gradient. A Canonical Correspondence Analysis (CCA) between the environmental variables and the plant communities produced a classification from which the conditions normally associated with the major plant communities were predicted. When projected as a digital map, the qualifying sites provided a testable hypothesis of the potential vegetation. The results of this study showed a definite grazing gradient, which reflects a change from a more mesic environment towards a more arid environment with an increase in utilisation pressure. The predictive vegetation model proved to be useful for predicting the occurrence of the valley thicket communities within the Eastern Cape.

From Summary: This is a geographical study of land use in the Eastern Cape Province. The land use pattern, although related closely to the features of the natural environment, is perhaps even more closely related to the spatial variations of the man-made environment, particularly to the disposition of the different racial groups with their different cultures and economies, and to the kaleidoscopic character of the settlement pattern.

Vegetation stress as a form of degradation is a widespread problem in many catchments in the Eastern Cape province. The Keiskamma is one of the catchments where considerable parts of the thicket biome are stressed. This necessitates an assessment of the status of the thicket biome by way of detecting vegetation stress in the area. The underpinnings of vegetation stress are investigated in this study. As a basic method to evaluate the thicket condition, remotely sensed data were acquired. High resolution ASTER imagery for the Keiskamma area at two different dates (2001 and 2005) was used to compute SVI and NDVI as indicators of vegetation stress conditions. A Digital Elevation Model (DEM) was used to derive slope angle and aspect. By way of digitizing from ortho-photo maps, various land-use types were mapped using Arc View GIS. The relationship between land use, terrain, soil erosion and vegetation stress was established. Field based techniques comprising stomatal conductance measurements were used and compared to remotely sensed data. The SVI and NDVI resultant images expressed similarities in areas depicting vegetation stress conditions at both epochs. A strong linear regression between NDVI and stomatal conductance measurements (mmol/m²) serve to confirm that the NDVI is a reliable indicator of vegetation stress condition. Slope angle and aspect were found to have a significant influence on vegetation stress conditions. Similarly variations in soil moisture and soil surface condition have strong implications for vegetation stress. Amongst other land-use types, abandoned lands were found to have the lowest NDVI values implying an association with the worst vegetation stress scenarios. It was concluded that an element of persistent stress conditions exists amongst the thicket vegetation of the Keiskamma catchment. This was mainly due to land use activities in the area.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, May 2016. / Globally, urban areas are the fastest growing land cover with significant numbers of people residing within these urban spaces. The continuous growth and expansion of urban settlements continue to exert unprecedented negative pressure on the natural environment, and green spaces are increasingly disappearing. In most intermediate and secondary cities of developing countries, loss of urban green spaces is partly due to the knowledge gap in urban planning as well as the lack of comprehensive assessment of the challenges and factors contributing to the deteriorations of urban spaces in these cities. In any given urban environment, green spaces of all types are acknowledged for creating valuable economic, social and environmental services. Urban green spaces are fast becoming means to sustainable development due to their extensive multifunctional roles and benefits to different users. This research focusses on critically assessing the relationship that exists between urban greenness and sustainable development in the city of UMhlathuze, KZN, South Africa. It also explores how urban greening is increasingly tied to urban planning and the challenges that urban greening faces in the context of rapidly increasing urbanisation. Results of this study show that there is increasing need to improve green spaces especially for low income groups who cannot afford to travel out of town to experience natural environments. Urban development therefore calls for stakeholders to follow the principles of sustainable development with reference to ecological systems in urban areas, including community green spaces, gardens, biodiversity, native species and urban green infrastructure. If urban greening is properly planned and integrated into urban development and planning policies, it can brings economic, social and environmental benefits to developing world cities. / GR 2016