Department of Entomology, Nanjing Agricultural University, Jiangsu, People's Republic of China.
Jiangsu Provincial Center for Disease Prevention and Control, Jiangsu, People's Republic of China.
Environ Monit Assess. 2018 Feb 20;190(3):152. doi: 10.1007/s10661-018-6516-7.
Key environmental factors and the mechanisms of their influence on the physicochemical habitats and macroinvertebrate communities of streams may vary among ecoregions. We studied the differences in environmental (land use and physicochemical) factors and the mechanisms of their influence on macroinvertebrate assemblages between mountain and lowland ecoregions in central China. We applied generalized linear models to identify key environmental factors that influence macroinvertebrate metrics consisting of taxa richness, Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa, percentages of EPT and intolerant individuals, and the Shannon-Wiener diversity index. Environmental factors and macroinvertebrate metrics significantly differed between the ecoregions. Mountain streams had significantly lower nutrients and %silt, but had twice higher total taxa richness than lowland streams. Watershed land uses were key drivers that influenced the physical habitat in the mountain ecoregion and were the main drivers that influenced both physical and chemical conditions in the lowland ecoregion. Correspondingly, watershed scale land uses, as well as physical and chemical variables, explained more variance in macroinvertebrate metrics than local-scale land uses in both mountain and lowland ecoregions. The overall biological variation was explained better by watershed-scale than by reach-scale land uses, whereas the spatial scale over which land use and physicochemical variables influence streams varied across ecoregions. Our results suggest that better landscape planning should be adopted for watershed management to improve water quality and physical habitat, and thus the conservation and restoration of macroinvertebrate biodiversity.
关键环境因素及其影响溪流理化生栖息地和大型无脊椎动物群落的机制可能因生态区而异。我们研究了中国中部山区和低地生态区之间环境（土地利用和理化）因素的差异及其对大型无脊椎动物组合的影响机制。我们应用广义线性模型来确定影响包括分类丰富度、蜉蝣目、石蝇目和毛翅目（EPT）类群、EPT 和不耐受个体的百分比以及香农-威纳多样性指数在内的大型无脊椎动物指标的关键环境因素。生态区之间的环境因素和大型无脊椎动物指标存在显著差异。山区溪流的养分和泥沙含量明显较低，但总分类丰富度是低地溪流的两倍。流域土地利用是影响山区生态区物理生境的关键驱动因素，也是影响低地生态区物理和化学条件的主要驱动因素。相应地，在山区和低地生态区，流域尺度的土地利用以及理化变量比局部尺度的土地利用对大型无脊椎动物指标的解释方差更大。与局部尺度土地利用相比，流域尺度土地利用对整体生物变异性的解释更好，而土地利用和理化变量影响溪流的空间尺度在生态区之间有所不同。我们的研究结果表明，应采取更好的流域景观规划来进行流域管理，以改善水质和物理生境，从而保护和恢复大型无脊椎动物生物多样性。
