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Earth Stewardship Science Research Institute Fracking in the Karoo: effects on vegetation K. Ellis 1, E.E. Campbell 1, M. De Wit 2 1: Nelson Mandela Metropolitan University, Botany Department, South Campus, Summerstrand, Port Elizabeth 2: Nelson Mandela Metropolitan University, Geology Department, South Campus, Summerstrand, Port Elizabeth Hydraulic fracturing or fracking is an extraction technique that is used to extract gas from rocks of low permeability. A number of companies have been either applied for, or been granted Exploration Rights for fracking in the Karoo. Shell’s application area is in the magisterial districts of Aberdeen, Beaufort-West, Carnarvon, Graaff-Reinet, Middelburg, Murraysburg, Noupoort, Richmond and Victoria-West and covers an area of approximately 30 000 km 2. The objectives of this study are to survey the proposed fracking areas and evaluate the flora of the area, highlighting Species of Conservation Concern. Furthermore, the study will investigate ecophysiological responses of Karoo plants to exposure to fracking fluid, with particular emphasis on phreatophytes. This study forms part of the AEON-ESSRI Baseline Research Program at NMMU that is undertaking a technical evaluation and socio-economic analyses of shale gas in the Eastern Cape. Introduction Study sites Exact locations of study sites will be decided by the Baseline Research Program; potential sites are shown in Figure 2. Although the exploration areas include many of the South African biomes, the most affected will be the Nama-Karoo and Thicket biomes (Figure 2). Figure 2: Biomes included in the shale gas exploration areas Preliminary research indicates a number of Species of Conservation Concern at risk in these areas should fracking go ahead. Both RARE, found in Nama-Karoo, Graaff- Reinet region Methods Vegetation Surveys: The Braun-Blanquet method of assessing total floristic compositions will be used. Cover– abundance values for each species within the plots will be estimated using the modified Braun-Blanquet cover–abundance scale. Brown et al. (2013) suggest a quadrat size of 25-100 m 2 for Nama-Karoo communities and 100-400 m 2 for Albany Thicket. Samples of each species present in a quadrat will be collected, identified and recorded. This element of the study aims to compile a species list for the areas most likely to be affected by fracking and highlight any Species of Conservation Concern (SCC’s). Boscia albitrunca (Burch.) Gilg & Gilg-Ben. Eco-physiological responses to fracking: The results of the vegetation survey will be used to select which species to use for the eco-physiological component of this study. An attempt will be made to include examples of all the major life forms represented in each of the biomes sampled. Boscia albitrunca has already been selected as a representative phreatophyte. Seeds of the selected species will either be wild harvested or bought from a nursery. They will be planted in the greenhouse at NMMU, and treated with a solution containing the most commonly used fracking chemicals (Table 1). Table 1: Chemicals most commonly used in fracking fluid (Ridley, 2011; Peduzzi & Harding Rohr Reis, 2013). Percentage seed germination will be assessed with the radicle emerged >1 mm taken as successful germination (Weiersbye & Witkowski, 2007). The application of fracking fluids to vegetation has been shown to cause severe damage and mortality (Adams, 2011) and effect biomass production (Takaki & Wolf, 2011). Biomass will be measured and mortality rate recorded. The condition (leaf condition, leaf colour, leaf fall) of the cultivated specimens will be visually observed over the study period. Chlorophyll fluorescence can be used as an indicator of a plant’s ability to tolerate environmental stresses (Maxwell & Johnson, 2000). A Plant Efficiency Analyzer will be used to measure stress in the plants treated with fracking fluid. Acknowledgements: Prof. E.E. Campbell & Prof. M. De Wit (Promoters). NMMU, Dormehl-Cunningham Trust, NMMU & Inkaba yeAfrica for funding. References: Adams, M.B. 2011. Land application of hydrofracturing fluids damages a deciduous forest stand in West Virginia. J. Environ. Qual. 40: 1340–1344. Brown, L.R., Du Preez, P.J., Bezuidenhout, H., Bredenkamp, G.J., Mostert, T.H.C. & Collins, N.B. 2013. Guidelines for phytosociological classifications and descriptions of vegetation in southern Africa. Koedoe 55(1), Art. #1103: 1-10. Golder Associates Africa, 2011. Volume 1: Environmental Management Plan, South Western Karoo Basin Gas Exploration Application: Central Precinct. Shell Exploration Company B.V. PASA Reference No. 12/3/220. For submission to the Petroleum Agency of South Africa. Golder Report Number: 12800-10534-29. 243pp. Maxwell, K. & Johnson, G.N. 2000. Chlorophyll fluorescence – a practical guide. Journal of Experimental Botany. Vol. 51, No. 345: 659-668. Peduzzi, P. & Harding Rohr Reis, R. 2013. Gas fracking: can we safely squeeze the rocks? Environmental Development, 2013, vol. 6, p. 86-99. Ridley, M. 2011. The Shale Gas Shock. The Global Warming Policy Foundation Report 2: 34pp. Takaki, S. & Wolf, D.C. 2011. Plant growth in soil amended with drilling mud. Discovery – the student journal of Dale Bumpers College of Agricultural, Food and Life Sciences. Vol. 12: 74-79. Weiersbye, I.M. & Witkowski, E.T.F. 2007. Impacts of acid mine drainage (AMD) on the regeneration potential of highveld phreatophyte plants. In J.J. Bester, A.H.W. Seydack, Vorster, T., Van der Merwe, I.J. and Dzivhani, S. (eds). Multiple Use Management of Natural Forests and Woodlands: Policy Refinements and Scientific Progress IV. Department of Water Affairs and Forestry of South Africa. www.dwaf.gov.za/forestry, pp 224-237. www.botanic.jp/plants-aa/animal.htm http://public.fotki.com/grootscholten/plant- collections/adromischusphotos/fallaxse.html Anisodontea malvastroides (Baker f.) Bates Adromischus fallax Toelken http://www.plantzafrica.com
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