0°-5° Preferred areas for any built infrastructure, Lowest lowest risk of erosion or instability, lowest 1 sensitivity construction and on-going maintenance costs. Gannaveld and Quartz Gannaveld habitat types are the most vulnerable to soil erosion due to limited soil retention capacity, as a Highest 5 result of sparse vegetation cover and root sensitivity systems. Soils are fine and silty and stones are generally lacking (J. Vlok, pers. comm.). Aquatic ecosystems (Freshwater streams & seepage areas; Rivers & floodplain) are High 4 highly sensitive to erosion, but are adapted sensitivity to periodic flooding. Gravel Arponveld, Apronveld, Ericaceous, Reyers et al. Mesic Proteoid, Quartz Apronveld, (2009) based Subalpine, Valley Thicket with Spekboom Moderate on major and Valley Thicket with Spekboom mosaics 3 sensitivity Soil erodibility habitat types habitat types are more densely vegetated of Vlok et al. and/or quite stony to assist with soil (2005). retention. Arid Proteoid, Mesic Renosterveld mosaic, Waboomveld, Arid Thicket mosaic, Arid Thicket mosaic with Spekboom, Restioid, Low 2 Mesic Renosterveld and Grassy habitat types sensitivity usually have dense root systems and good vegetation cover to retain soil. Asteraceous, Sandolien, Thicket mosaics, Quartz Asbosveld; Arid Renosterveld Mosaics; Scholtzbosveld, Ranteveld and Lowest 1 Kalkveld habitat types generally have a good sensitivity and dense perennial vegetation cover with well-developed root systems that retain soil. Highest Within 200m of perennial river 5 sensitivity 1: 50 000 Rivers NGI Rivers Highest Within 100m of non-perennial river 5 sensitivity Highest Wetland 5 sensitivity Wetlands NFEPA High Within 200m of wetlands 4 sensitivity Biome Rivers and habitat types Highest DRAIN River and Source stream 5 Biodiversity floodplains from (Vlok et sensitivity al. 2005) Conservation Highest Critically Endangered 5 status of sensitivity Vegetation Little Karoo High status Endangered 4 vegetation sensitivity units (Reyers Vulnerable Moderate 3
0°-5° Preferred areas for any built infrastructure, lowest risk of erosion or instability, lowest construction and on-going maintenance costs. Lowest sensitivity 1 Soil erodibility Reyers et al. (2009) based on major habitat types of Vlok et al. (2005). Gannaveld and Quartz Gannaveld habitat types are the most vulnerable to soil erosion due to limited soil retention capacity, as a result of sparse vegetation cover and root systems. Soils are fine and silty and stones are generally lacking (J. Vlok, pers. comm.). Highest sensitivity 5 Aquatic ecosystems (Freshwater streams & seepage areas; Rivers & floodplain) are highly sensitive to erosion, but are adapted to periodic flooding. High sensitivity 4 Gravel Arponveld, Apronveld, Ericaceous, Mesic Proteoid, Quartz Apronveld, Subalpine, Valley Thicket with Spekboom and Valley Thicket with Spekboom mosaics habitat types are more densely vegetated and/or quite stony to assist with soil retention. Moderate sensitivity 3 Arid Proteoid, Mesic Renosterveld mosaic, Waboomveld, Arid Thicket mosaic, Arid Thicket mosaic with Spekboom, Restioid, Mesic Renosterveld and Grassy habitat types usually have dense root systems and good vegetation cover to retain soil. Low sensitivity 2 Asteraceous, Sandolien, Thicket mosaics, Quartz Asbosveld; Arid Renosterveld Mosaics; Scholtzbosveld, Ranteveld and Kalkveld habitat types generally have a good and dense perennial vegetation cover with well-developed root systems that retain soil. Lowest sensitivity 1 Biodiversity Rivers 1: 50 000 NGI Rivers Within 200m of perennial river Highest sensitivity 5 Within 100m of non-perennial river Highest sensitivity 5 Wetlands NFEPA Wetland Highest sensitivity 5 Within 200m of wetlands High sensitivity 4 Rivers and floodplains Biome habitat types from (Vlok et al. 2005) DRAIN River and Source stream Highest sensitivity 5 Vegetation status Conservation status of Little Karoo vegetation units (Reyers Critically Endangered Highest sensitivity 5 Endangered High sensitivity 4 Vulnerable Moderate 3