Bothalia - African Biodiversity & Conservation ISSN: (Online) 2311-9284, (Print) 0006-8241 Page 1 of 10 Original Research Assessing habitat fragmentation of the KwaZulu-Natal Sandstone Sourveld, a threatened ecosystem Authors: Background: The KwaZulu-Natal Sandstone Sourveld (KZN SS) is a grassland ecosystem 1 Rowan Naicker categorised as endangered by the terms of the National Environmental Management: Mathieu Rouget1 Onisimo Mutanga1 Biodiversity Act (Act 10 of 2004). Pressure from urbanisation has led to the remaining areas of the KZN SS being physically fragmented, causing low connectivity levels which have Affiliations: diminished the biological persistence of this ecosystem. 1School of Agricultural, Earth and Environmental Sciences, Objectives: This study aimed to quantify the overall level of habitat fragmentation of the KZN University of KwaZulu-Natal, SS and determine the level of connectivity within the ecosystem, and patches of the KZN SS South Africa occurring in the eThekwini Municipal area. Using graph theory, we compared the effectiveness Research Project no.: of broad-scale and fine-scale data sets in quantifying habitat fragmentation. NRF grant no 84157 Methods: The Conefor Sensinode software, which employs the bases of graph theory, was Corresponding author: chosen to aid in assessing fragmentation levels. The integral index of connectivity (IIC) (values Mathieu Rouget, range from 0 to 1, with 1 highlighting optimal connectivity) was chosen as the best index to
[email protected] determine landscape connectivity. Dates: Results: The KZN SS was shown to be highly fragmented, especially at dispersal distances less Received: 23 May 2016 than 500 m. This resulted in very low connectivity levels, with the highest IIC value recorded Accepted: 19 Sept.