Impacts of anthropogenic disturbances on plant species diversity in fragmented landscapes

当前的生物多样性危机促进了景观变化对当地物种多样性影响的研究。其中，栖息地的丧失和破碎化已被证明会改变孤立生态系统的物种多样性，并促进外来物种的入侵。景观配置的空间成分已成功地与这些破碎化栖息地中物种多样性的改变联系起来。然而，现代物种多样性能够更好地反映历史景观格局，这可能意味着在没有额外栖息地丧失或破碎化的情况下，孤立栖息地物种组成的进一步变化。在预测生境丧失对当地物种多样性的实际影响时，应同时采用空间和时间尺度。外来物种也被认为是本地物种减少的一个原因。然而，对外来物种的研究大多集中在相关性上，外来物种实际影响的经验证据还很薄弱。我的研究计划的长期目标是促进一般生态学理论的发展，预测人为干扰对破碎景观中物种多样性的影响。我的研究重点是湿地，打算1)测量现在和过去的景观配置对湿地植被的影响，2)实验评估湿地干扰、外来入侵和本地物种减少之间的因果关系。本研究计划在植物生态学和生态系统管理之间的前沿解决关键问题。在一个生物多样性下降的世界里，解决植物多样性如何受到区域和地方进程的影响是一个至关重要的问题。

The current biological diversity crisis has encouraged research on the impact of transformed landscapes on local species diversity. Among others, habitat loss and fragmentation have been shown to modify species diversity of isolated ecosystems and to promote exotic species invasions. Spatial components of landscape configuration have been successfully associated with modified species diversity in these fragmented habitats. However, present-day species diversity could better reflect historical landscape configuration, which could imply further changes in species composition of isolated habitats without additional habitat loss or fragmentation. Both spatial and temporal scales should be used to predict the real impact of habitat loss on local species diversity. Exotic species have also been identified as a causing agent in native species decline. However, studies on exotic species have mostly focused on correlations and empirical evidences of the real impact of exotic species are still weak. The long term objective of my research program is to contribute to the development of general ecological theories predicting the impacts of anthropogenic disturbances on species diversity in fragmented landscapes. My research is focused on wetlands and intends 1) to measure the impact of present and past landscape configuration on wetland vegetation and 2) to assess experimentally the causal link between disturbances, exotic invasion, and native species decline in wetlands. This research program addresses crucial questions at the frontier between plant ecology and ecosystem management. In a world of declining biodiversity, addressing how plant diversity is influenced by both regional and local processes is of critical concern.