Modelling the spatio-temporal dispersal of benthic macroinvertebrates in rivers as a tool for predicting recolonization

越来越多的河流修复项目以改善水文地貌特征为目标。然而，其中几个项目没有对生物群产生预期的影响，在对敏感的底栖无脊椎动物物种恢复的地点进行重新殖民化方面也失败了。一个被广泛接受的假说是，底栖无脊椎动物物种的扩散能力限制和控制了恢复的河段的再定殖化，然而，很少有人对这一假说进行验证。该项目旨在开发和验证底栖无脊椎动物物种在其水生和陆地生命阶段的栖息地和扩散模型，以更好地了解和预测它们在恢复的河段定居的能力。我们将采用循序渐进的方法，为两个流域和四个底栖无脊椎动物物种建立基于网格的地理信息系统栖息地和扩散模型，代表不同的扩散机制和生活策略。栖息地模型将预测模式物种的栖息地适宜性和空间分布。水生和陆地环境中的扩散模型将基于将环境变量转换为描述物种扩散障碍效应的“成本”。栖息地和扩散模型的结果将通过实地调查进行验证。通过对个体扩散模型的比较，确定底栖无脊椎动物群落的一般扩散路径。

An increasing number of river restoration projects targets the improvement of hydromorphological features. Several of these projects, however, have not had the anticipated effects on the biota and failed in terms of recolonization of restored sites by sensitive benthic inver-tebrate species. A widely accepted hypothesis is that dispersal abilities of benthic invertebrate species limit and control recolonization of restored river sections, however, little effort has been spent on the verification of this hypothesis. This project aims at the development and validation of habitat and dispersal models for benthic invertebrate species during their aquatic and terrestrial life stages to better understand and predict their ability to colonize restored river sections. Applying a stepwise approach we will develop grid-based GIS habitat and dispersal models for two catchments and four benthic invertebrate species, representing different dispersal mechanisms and life strategies. The habitat models will predict habitat suitability and spatial distribution of the model species. Models for the dispersal in the aquatic and terrestrial environment will be based on the conversion of environmental variables into “costs” describing the barrier effect on the dispersal of a species. The results of the habitat and dispersal models will be validated by field investigations. Through the comparison of the individual dispersal models we will identify general dispersal pathways for the benthic invertebrate community.