Rethinking biodiversity patterns and processes in stream ecosystems
Rethinking biodiversity patterns and processes in stream ecosystems
复制标题
重新思考河流生态系统中的生物多样性模式和过程
DOI：
10.1002/ecm.1520
复制
发表时间：
2022
影响因子：
6.1
通讯作者：
Spasojevic, Marko J.
中科院分区：
文献类型：
--
作者：
Green, Matthew D.;Anderson, Kurt E.;Herbst, David B.;Spasojevic, Marko J.
群落生态学的一个主要目标是了解负责产生生物多样性模式的过程沿着空间和环境梯度。在河流生态系统中，系统特定的概念框架已经主导了描述生物多样性变化的研究沿着纵向梯度的河流网络。然而，对这些概念框架的支持有好有坏，主要适用于特定的河流生态系统和生物群落，这些框架对驱动生物多样性模式的一般机制的重视程度较低。重新思考溪流生态系统中的生物多样性模式和过程，重点是跨生态系统的总体机制，将提供一个更全面的理解，为什么生物多样性模式不同沿着河流网络。在这项研究中，我们应用生态群落（TEC）的概念框架理论流生态系统的核心生态过程结构社区：扩散，物种形成，生态位选择，生态漂移明确的重点。使用一个独特的案例研究，从高海拔网络连接的湖泊和溪流，我们采样流无脊椎动物群落在塞拉利昂内华达州，加州，美国测试建立流生态框架，并比较它们与TEC框架。从源头向下游移动，局部多样性增加，β多样性减少，这与河流连续体概念和山溪生物多样性的小而强大的框架一致。当地的多样性也结构的距离低于上游湖泊，多样性增加与距离低于上游湖泊，在支持序列不连续的概念。尽管溪流生态框架预测的生物多样性模式得到了一些支持，但没有一个框架得到完全支持，这表明“背景依赖性”。通过将我们的结果框架在TEC下，我们发现物种多样性是由生态位选择结构化的，在环境有利的地点，当地的多样性最高。当地的多样性也是最高的网站与小社区规模，对抗预测的生态漂移的影响。此外，较高的β多样性在源头的扩散和生态位选择的影响，环境恶劣和空间隔离的网站表现出较高的社区变化。总之，我们的研究结果表明，将系统特定的生态框架与TEC相结合，为推断驱动生物多样性模式的机制提供了一种强有力的方法，并为跨生态系统的生物多样性研究的推广提供了一条道路。
A major goal of community ecology is understanding the processes responsible for generating biodiversity patterns along spatial and environmental gradients. In stream ecosystems, system‐specific conceptual frameworks have dominated research describing biodiversity change along longitudinal gradients of river networks. However, support for these conceptual frameworks has been mixed, mainly applicable to specific stream ecosystems and biomes, and these frameworks have placed less emphasis on general mechanisms driving biodiversity patterns. Rethinking biodiversity patterns and processes in stream ecosystems with a focus on the overarching mechanisms common across ecosystems will provide a more holistic understanding of why biodiversity patterns vary along river networks. In this study, we apply the theory of ecological communities (TEC) conceptual framework to stream ecosystems to focus explicitly on the core ecological processes structuring communities: dispersal, speciation, niche selection, and ecological drift. Using a unique case study from high‐elevation networks of connected lakes and streams, we sampled stream invertebrate communities in the Sierra Nevada, California, USA to test established stream ecology frameworks and compared them with the TEC framework. Local diversity increased and β‐diversity decreased moving downstream from the headwaters, consistent with the river continuum concept and the small but mighty framework of mountain stream biodiversity. Local diversity was also structured by distance below upstream lakes, where diversity increased with distance below upstream lakes, in support of the serial discontinuity concept. Despite some support for the biodiversity patterns predicted from the stream ecology frameworks, no single framework was fully supported, suggesting “context dependence.” By framing our results under the TEC, we found that species diversity was structured by niche selection, where local diversity was highest in environmentally favorable sites. Local diversity was also highest in sites with small community sizes, countering the predicted effects of ecological drift. Moreover, higher β‐diversity in the headwaters was influenced by dispersal and niche selection, where environmentally harsh and spatially isolated sites exhibit higher community variation. Taken together our results suggest that combining system‐specific ecological frameworks with the TEC provides a powerful approach for inferring the mechanisms driving biodiversity patterns and provides a path toward generalization of biodiversity research across ecosystems.