O'Connor T G, Kuyler P
Centre for African Ecology, School of A.P.E.S., University of the Witwatersrand, P.O. WITS 2050, Johannesburg, South Africa.
J Environ Manage. 2009 Jan;90(1):384-95. doi: 10.1016/j.jenvman.2007.10.012. Epub 2007 Dec 21.
South Africa's moist grassland harbours globally significant biodiversity, supplies essential ecosystem services, supports crop and livestock agriculture, forestry and settlement, yet is poorly conserved. Ongoing transformation and limited opportunity for expanding the protected area network require instead that biodiversity conservation is 'mainstreamed' within other land uses. This exercise sought to identify the relative compatibility of 10 land uses (conservation, livestock or game ranching, tourism/recreation, rural settlement, dryland cropping, irrigated cropping, dairy farming, plantation forestry, and urban settlement) with maintaining biodiversity integrity. This was assessed using 46 indicators for biodiversity integrity that covered landscape composition, structure, and functioning. Data was integrated into a single measure per land use through application of the analytic hierarchy process, with supporting information gained from interviews with experts. The rank order of importance amongst indicators was landscape structure, functioning and composition. Consistent differences among land uses for all three categories revealed two clear groupings. Conservation, livestock or game ranching had the lowest impact and retained substantial natural asset, while that for tourism/recreation was intermediate. All other land uses had a severe impact. Impact on biodiversity integrity depended mainly on the extent of transformation and fragmentation, which accounted for the greatest impact on habitats and species, and impairment of landscape functioning. It is suggested that a strategic intervention for maintaining biodiversity integrity of moist grassland is to support livestock or game ranching and limit ongoing urban sprawl.
南非湿润的草原拥有具有全球重要意义的生物多样性,提供重要的生态系统服务,支撑着作物和畜牧农业、林业及定居点,但却未得到良好保护。当前的土地利用转型以及扩大保护区网络的机会有限,这就要求将生物多样性保护在其他土地利用方式中“主流化”。本研究旨在确定10种土地利用方式(保护、畜牧或狩猎牧场经营、旅游/休闲、农村定居点、旱地作物种植、灌溉作物种植、奶牛养殖、人工林、城市定居点)与维护生物多样性完整性之间的相对兼容性。通过使用涵盖景观组成、结构和功能的46个生物多样性完整性指标对此进行评估。通过应用层次分析法,将数据整合为每种土地利用方式的单一衡量指标,并从专家访谈中获取辅助信息。指标中重要性的排序依次为景观结构、功能和组成。所有这三类土地利用方式之间存在一致的差异,形成了两个明显的类别。保护、畜牧或狩猎牧场经营的影响最小,保留了大量自然资产,而旅游/休闲的影响处于中等水平。所有其他土地利用方式都有严重影响。对生物多样性完整性的影响主要取决于土地利用转型和碎片化的程度,这对栖息地和物种的影响最大,同时也损害了景观功能。建议维护湿润草原生物多样性完整性的一项战略干预措施是支持畜牧或狩猎牧场经营,并限制城市的持续扩张。