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工程以改善水文形态特征为目标。然而，这些项目中有几个没有对生物群产生预期的影响，并且在敏感的底栖无脊椎动物物种重新定居恢复地点方面失败了。一个被广泛接受的假设是底栖无脊椎动物物种的扩散能力限制和控制了恢复河段的再定域，然而，对这一假设的验证却很少。本项目旨在开发和验证底栖无脊椎动物在其水生和陆生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河段的殖民能力。采用分步方法，我们将为两个流域和四种底栖无脊椎动物物种开发基于网格的GIS栖息地和扩散模型，代表不同的扩散机制和生命策略。生境模型可以预测模式种的生境适宜性和空间分布。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屏障对物种扩散影响的“成本”。生境和扩散模型的结果将通过实地调查得到验证。通过个体扩散模型的比较，我们将确定底栖无脊椎动物群落的一般扩散途径。

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.