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Vlok 2009. Ecosystem services, land-cover change, and stakeholders: finding a sustainable foothold for a semiarid biodiversity hotspot. Ecology and Society 14(1): 38. [online] ABSTRACT. Land-cover change has been identified as one of the most important drivers of change in ecosystems and their services. However, information on the consequences of land cover change for ecosystem services and human well-being at local scales is largely absent. Where information does exist, the traditional methods used to collate and communicate this information represent a significant obstacle to sustainable ecosystem management. Embedding science in a social process and solving problems together with stakeholders are necessary elements in ensuring that new knowledge results in desired actions, behavior changes, and decisions. We have attempted to address this identified information gap, as well as the way information is gathered, by quantifying the local-scale consequences of land-cover change for ecosystem services in the Little Karoo region, a semiarid biodiversity hotspot in South Africa. Our work is part of a stakeholder-engaged process that aims to answer questions inspired by the beneficiaries and managers of ecosystem services. We mapped and quantified the potential supply of, and changes in, five ecosystem services: production of forage, carbon storage, erosion control, water flow regulation, and tourism. Our results demonstrated substantial (20%-50%) declines across ecosystem services as a result of land-cover change in the Little Karoo. We linked these changes in land-cover to the political and land-use history of the region. We found that the natural features that deliver the Little Karoo's ecosystem services, similar to other semiarid regions, are not being managed in a way that recognizes their constraints and vulnerabilities. There is a resulting decline in ecosystem services, leading to an increase in unemployment and vulnerability to shocks, and narrowing future options. We have proposed a way forward for the region that includes immediate action and restoration, mechanisms to fund this action, the development of future economic activity including tourism and carbon markets, and new ways that the science-stakeholder partnership can foster these changes. Although we acknowledge the radical shifts required, we have highlighted the opportunities provided by the resilience and adaptation potential of semiarid regions, their biodiversity, and their inhabitants.Safriel and his colleagues feeling optimistic about the potential for these social-ecological systems to alleviate the current low levels of human well-being. We remain hopeful that the Little Karoo too can follow this course, but acknowledge that the individual, economic, institutional, and political requirements are significant and wide ranging, and for the most part, are not currently in existence.Responses to this article can be read online at: . 2007. The future of production systems in a globalized world. Frontiers in Ecology and the Environment 5:191-198. ...

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According to the equilibrium theory of island biogeography, insularisation will lead to species loss from habitat remnants. Extinctions will continue untill species number equilibrates at a level appropriate for the size and isolation of the island remnants. We tested whether insularisation leads to species loss by comparing plant species numbers on islands of fynbos shrublands surrounded by Afrotemperate evergreen forest with extensive "mainland" tracts of fynbos. Species area curves for islands and subsamples of mainland had significantly different slopes (z =0.43, z=0.16). Small islands had the fewest species (less than one fifth) relative to mainland samples of similar size. The species area curves intersect at 590 ha so that reserve sizes of this order of magnitude are needed to avoid species losses relative to extensive areas of fynbos.We compared traits of species on islands and mainlands to determine processes most affected by insularisation. Island floras did not differ from the mainland in the mix of dispersal types, pollinator syndromes or proportion of dioecious species. Islands did have significantly fewer species of low stature and significantly more species that survive fire only as seed and not by resprouting. We infer that the main cause of species loss is change in disturbance frequency. Islands have fewer fires and lose species dependent on frequent fires. We predict that island effects could be reduced by judicious fire management of small reserves.