Biology Department, McGill University, Montréal, Québec, Canada.
Am Nat. 2010 Sep;176(3):289-302. doi: 10.1086/655426.
We add an ecosystem perspective to spatially structured communities subject to colonization-extinction dynamics. We derive a plant-based metaecosystem model to analyze how the spatial flows of the biotic and abiotic forms of a limiting nutrient affect persistence and coexistence. We show that the proportion of patches supporting plants in a region has a considerable impact on local nutrient dynamics. Then we explicitly couple nutrient dynamics to patch dynamics. Our model shows strong feedback between local and regional dynamics mediated by nutrient flows. We find that nutrient flows can have either positive or negative effects on species persistence and coexistence. The essential feature of this local-regional coupling is the net direction of the nutrient flows between occupied and empty patches. A net flow of nutrients from occupied to empty patches leads to indirect facilitative interactions, such as an inferior competitor promoting the persistence of a superior competitor. We show that nutrient flows affect the potential diversity of the metaecosystem and key features of plant community dynamics, such as the shape of the competition-colonization trade-off and successional sequences. Our analysis revealed that integrating ecosystem and spatial dynamics can lead to various indirect interactions that contribute significantly to community organization.
我们从生态系统角度出发，研究了处于定居-灭绝动态下的空间结构群落。我们提出了一个基于植物的元生态系统模型，以分析限制养分的生物和非生物形式的空间流动如何影响持久性和共存。我们表明，一个地区支持植物的斑块比例对当地养分动态有相当大的影响。然后，我们将养分动态明确地与斑块动态联系起来。我们的模型显示，养分流动通过反馈对本地和区域动态产生强烈影响。我们发现，养分流动对物种持久性和共存可能产生积极或消极的影响。这种局部-区域耦合的基本特征是占据斑块和空斑块之间养分流动的净方向。养分从占据斑块流向空斑块会导致间接的促进作用，例如，一个较差的竞争者促进了一个较好的竞争者的持久性。我们表明，养分流动会影响元生态系统的潜在多样性以及植物群落动态的关键特征，例如竞争-定居权衡的形状和演替序列。我们的分析表明，整合生态系统和空间动态可以产生各种间接相互作用，这些相互作用对群落组织有重要贡献。
