The role of land use, nutrients, and other stressors in shaping benthic invertebrate assemblages in Slovenian rivers

作者：Pavlin Maja^*; Birk Sebastian; Hering Daniel; Urbanic Gorazd

来源：Hydrobiologia, 2011, 678(1): 137-153.

DOI：10.1007/s10750-011-0836-8

• Benthic invertebrates
• Variance partitioning
• Multiple stressors
• Organic pollution
• Eutrophication
• Land use

Studying human impacts on riverine systems is challenging due to the natural diversity and multiple stressors that are co-occurring. The term stressor(s) refers to variable(s) of anthropogenic landscape changes and local abiotic stream conditions that reflect human activities. We compared the effects of different stressors and natural (typology) factors on benthic invertebrate assemblages in Slovenian rivers. A total of 270 river sites located in four European ecoregions were sampled, covering the gradient of human perturbation ranging from (near) natural to highly degraded/polluted. Stressors commonly affecting running waters were grouped into management-relevant stressor-groups: land use (percentage of urban, intensive and non-intensive agricultural, and natural land use in the catchment and sub-catchment), eutrophication (in-stream concentrations of phosphorus and nitrogen compounds) and other stressors (e. g., organic pollution, hydromorphological alteration). We compared the effects of the stressor-groups on invertebrate assemblages using partial Canonical Correspondence Analysis and tested the explanatory power of each stressor-group using typology variables as covariates. Stressors and typology variables showed high independent effects (40-65%) on invertebrate assemblages despite considerable joint effects from land use and typology. Stressors' pure effects accounted for 70%, and interactions among the stressor-groups made up the remaining 30% of the total explained variability. Altogether, this study gives a good perspective on the ability to separate the effects of anthropogenic stressors from natural causes, as well as to separate effects among groups of stressors. Against this background, we advocate stressor-specific analyses to provide or improve guidelines for selecting appropriate measures to enhance the river status.

• 出版日期2011-12