南水北调中线水源地河流大型无脊椎动物多样性对人类干扰的响应

Increasing human disturbances have dramatically altered lotic biodiversity both regionally and globally. However, the knowledge about the patterns, processes and mechanisms linked to human-induced intervention driving the multidimensional loss of biodiversity in streams and rivers remains yet limited, particularly in phylogenetic and functional diversity. Here, we address this issue by choosing five rivers representing different levels of human disturbances, located in the source region of the Middle Route of South-North Water Diversion Project, as one-case study. The aims of this study concentrate mainly on the impacts of anthropogenic activities on three aspects (alpha, beta and gamma) of taxonomic, phylogenetic and functional diversity of macroinvertebrates in these rivers. Firstly, we depict the key patterns of taxonomic, phylogenetic and functional diversity between and within the five rivers, and identify their spatial and temporal differences. Secondly, we detect the key driving extrinsic (both naturally- and human-induced environmental variables) and intrinsic factors (representing by spatial factors), integrate them into one proposed framework, and partition their relative contribution to respective diversity patterns (especially patterns of beta diversity). Finally, we will establish the quantitative relationships between macroinvertebrate diversity and the stress of anthropogenic activities based on above studies, to predict and assess the impact of human interventions on species composition, evolutionary history and functional roles of biodiversity. These stereoscopic and multidimentional scientific probes should remarkably rich the knowledge about lotic macroinvertebrate diversity, enhance understanding of the biodiversity alterations involving community phylogenetic and functional traits, and promote in-depth explorating the association between biodiversity loss and ecosystem multifunction. These results can provide important implications for river restoration, landscape assessment, management and conservation planning in the water source region.

日益加剧的人类干扰已显著改变河流生物多样性。而对生物多样性在不同维度上对人类干扰响应的关键过程和机制的认识仍然十分有限，尤其在系统发育和功能多样性方面。项目拟选择南水北调中线水源地的代表性河流，以大型无脊椎动物为研究对象，开展物种、系统发育和功能多样性各自在α、β和γ三个层次对人类干扰的响应研究。首先，在人类干扰梯度下，描述三种维度的α、β和γ多样性在不同河流和干扰强度下的时空差异及水平。其次，甄别出驱动这些格局变化的关键空间因子和环境因子，解析它们各自/联合的作用力大小、方向和水平。最后，在系统把握关键驱动要素的基础上，构建无脊椎动物多样性对人类干扰响应的预测模型，预测和评估人类干扰对无脊椎动物物种组成、进化历史和功能的影响。本研究尝试整合多样性的三个维度来探索人类干扰对无脊椎动物多样性影响的过程和机制，可为水源地河流生物多样性评价、流域系统管理、修复和保护等提供科学支撑。