The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China.
The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
Sci Total Environ. 2019 Mar 10;655:1288-1300. doi: 10.1016/j.scitotenv.2018.11.222. Epub 2018 Nov 20.
Examining the relative contribution of local environmental stressors and regional factors in structuring biological communities is essential for biodiversity conservation and environmental assessment, yet their relative roles for different community characterizations remain elusive. Here, we examined the responses of taxonomic and functional structures of stream macroinvertebrate communities to local and regional factors across a human-induced environmental gradient in the Han River Basin, one subtropical biodiversity hotspot in China. Our objectives were: 1) to examine the responses of traditional taxonomic measures and functional traits to anthropogenic disturbances; 2) to compare the relative importance of environmental versus spatial variables and catchment-scale versus reach-scale variables for the two community characterizations. We found that both species and trait compositions performed well in differentiating anthropogenic disturbances, indicating that both taxonomic and functional structures of macroinvertebrate communities were strongly altered by human activities. Particularly, some traits related to life history (e.g., voltinism), resilience and resistance (e.g., adult flying ability) are well suited for predicting changes of communities towards anthropogenic disturbances owing to their mechanistic relationship with environmental gradients. We found that environmental variables played more important roles than spatial effects in structuring both taxonomic and functional facets of macroinvertebrate communities. Environmental filtering was more important in determining functional than taxonomic structure, and the opposite was true for spatial effects. In terms of environmental variables, catchment land-uses played the primary role in determining taxonomic composition, whereas reach-scale variables related to local habitat heterogeneity were more influential for functional structure. Our study highlights the importance of employing metacommunity perspectives and different community characterizations in both theoretical and applied research. For stream bioassessment and management, we argue that the combination of taxonomic and functional characterizations of community should be implemented, as different facets of biological communities responded to different types of anthropogenic disturbances.
研究生物群落结构中局部环境胁迫和区域因素的相对贡献，对于生物多样性保护和环境评估至关重要，但它们对不同群落特征的相对作用仍不清楚。在这里，我们研究了在汉河流域这个中国亚热带生物多样性热点地区的人为环境梯度上，宏观溪流无脊椎动物群落的分类和功能结构对局部和区域因素的响应。我们的目标是：1）研究传统分类测量和功能特征对人为干扰的响应；2）比较环境与空间变量以及集水区尺度与河段尺度变量对这两种群落特征的相对重要性。我们发现，物种和特征组成都很好地区分了人为干扰，表明人为活动强烈改变了无脊椎动物群落的分类和功能结构。特别是，一些与生活史（如多型性）、弹性和抵抗力（如成虫飞行能力）有关的特征，由于与环境梯度的机制关系，非常适合预测社区向人为干扰的变化。我们发现，在构建无脊椎动物群落的分类和功能方面，环境变量比空间效应更为重要。环境过滤在确定功能结构方面比分类结构更为重要，而空间效应则相反。就环境变量而言，集水区土地利用在决定分类组成方面起着主要作用，而与局部生境异质性有关的河段尺度变量对功能结构的影响更大。我们的研究强调了在理论和应用研究中采用集合群落观点和不同群落特征的重要性。对于溪流生物评估和管理，我们认为应该实施群落的分类和功能特征的组合，因为不同的生物群落特征对不同类型的人为干扰有不同的响应。
