| Summary: | Conservation and management of the ecology of natural areas has become a prerequisite for
mining companies in South Africa. Systematic conservation planning provides a useful tool for
land–use planning and impact assessment, particularly in the mining industry. A study was
therefore undertaken to provide sufficient, spatially explicit biodiversity and veld condition
information to aid in the development and establishment of an official conservation plan for the
leased mining area of Impala Platinum. By identifying areas with high plant diversity or
endemism and by assessing veld conditions as well as grazing and browsing capacities,
recommendations could be made towards management strategies and potential future land–use
practices.
The licensed mining area, north of Rustenburg, covers 29334 ha and includes 14 operational
shafts. The area was stratified into three main categories based on landscape types namely:
norite koppies; thornveld and rehabilitated areas. The Braun Blanquet approach was followed to
sample 139 stratified random relevés. Additional computer software packages were used for
capturing, processing and presentation of the phytosociological data (TURBOVEG) as well as a
visual editor for phytosociological tables (MEGATAB). Ordinations were subsequently
performed to confirm the plant communities and illustrate possible environmental gradients,
using multivariate statistic analyses (CANOCO). Four plant communities with two subcommunities
were identified and described in both the norite koppies and thornveld respectively
while three plant communities with three sub–communities were identified in the rehabilitated
areas. Specific environmental factors that influence plant community structure and composition
in the norite koppies were the aspect and percentage of soil surface rockiness while soil types
proved to be the distinguishing factor in the thornveld. The distribution of plant communities in
the rehabilitated areas is mainly due to anthropogenic influences rather than any environmental
factors.
The Fixed Point Monitoring of Vegetation Methodology– FIXMOVE was then used to sample 32
stratified random survey plots in four selected plant communities in order to quantify and
compare veld conditions as well as grazing and browsing capacities. The determination of
landscape functionality served to support these quantitative results. The Landscape Function
Analysis (LFA) method was used for this purpose. Multivariate statistic analyses (CANOCO)
were used to indicate possible degradation gradients between the plant communities.
Conclusions regarding conservation and management units were reached by interpreting the
quantitative data in accordance with the phytosociological results and recommendations could
then be made. All the norite koppies plant communities were recommended as areas for The Fixed Point Monitoring of Vegetation Methodology– FIXMOVE was then used to sample 32
stratified random survey plots in four selected plant communities in order to quantify and
compare veld conditions as well as grazing and browsing capacities. The determination of
landscape functionality served to support these quantitative results. The Landscape Function
Analysis (LFA) method was used for this purpose. Multivariate statistic analyses (CANOCO)
were used to indicate possible degradation gradients between the plant communities.
Conclusions regarding conservation and management units were reached by interpreting the
quantitative data in accordance with the phytosociological results and recommendations could
then be made. All the norite koppies plant communities were recommended as areas for
ii
conservation because of unique and high biodiversity and anthropogenic threats. The Eragrostis
rigidior–Ziziphus mucronata and Acacia caffra–Bothriochloa insculpta Communities in the
thornveld showed the best potential for browsing and grazing practices but were also
recommended for conservation because of their high species diversity and anthropogenic
threats. The high landscape functionality, veld condition and grazing capacity of the Aristida
bipartita–Bothriochloa insculpta Community indicated that the rehabilitation of the opencast
mining areas had been relatively successful at the time of the surveys. Selected parts of the
Indigofera heterotricha–Aristida bipartita Community were also recommended for conservation
and management in the form of controlled and more effective grazing strategies were
recommended for the rest of the thornveld. === Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2011.
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