Damschen Ellen I, Brudvig Lars A, Haddad Nick M, Levey Douglas J, Orrock John L, Tewksbury Joshua J
Department of Biology, Washington University, Campus Box 1137, St. Louis, MO 63130, USA.
Proc Natl Acad Sci U S A. 2008 Dec 9;105(49):19078-83. doi: 10.1073/pnas.0802037105. Epub 2008 Dec 5.
A conceptual model of movement ecology has recently been advanced to explain all movement by considering the interaction of four elements: internal state, motion capacity, navigation capacities, and external factors. We modified this framework to generate predictions for species richness dynamics of fragmented plant communities and tested them in experimental landscapes across a 7-year time series. We found that two external factors, dispersal vectors and habitat features, affected species colonization and recolonization in habitat fragments and their effects varied and depended on motion capacity. Bird-dispersed species richness showed connectivity effects that reached an asymptote over time, but no edge effects, whereas wind-dispersed species richness showed steadily accumulating edge and connectivity effects, with no indication of an asymptote. Unassisted species also showed increasing differences caused by connectivity over time, whereas edges had no effect. Our limited use of proxies for movement ecology (e.g., dispersal mode as a proxy for motion capacity) resulted in moderate predictive power for communities and, in some cases, highlighted the importance of a more complete understanding of movement ecology for predicting how landscape conservation actions affect plant community dynamics.
最近提出了一个运动生态学概念模型，通过考虑内部状态、运动能力、导航能力和外部因素这四个要素的相互作用来解释所有运动。我们修改了这个框架，以生成关于破碎化植物群落物种丰富度动态的预测，并在一个7年时间序列的实验景观中对其进行了测试。我们发现，两个外部因素，即传播媒介和栖息地特征，影响了栖息地片段中的物种定殖和再定殖，它们的影响各不相同，且取决于运动能力。鸟类传播的物种丰富度显示出连通性效应，随着时间的推移达到渐近线，但没有边缘效应，而风传播的物种丰富度显示出边缘和连通性效应稳步累积，没有渐近线的迹象。无辅助传播的物种也显示出随着时间的推移连通性导致的差异增加，而边缘没有影响。我们对运动生态学代理指标的有限使用（例如，以传播方式作为运动能力的代理指标）导致对群落的预测能力中等，并且在某些情况下，突出了更全面理解运动生态学对于预测景观保护行动如何影响植物群落动态的重要性。
