Aquatic plants–based risk model for assessment of ecological safety of rivers

In order to ensure the ecological safety in river beds, each project affecting it must be subjected to an evaluation in terms of its implementation results on the river habitats. Technical activities in the river beds can cause irreversible changes in their biocenosis. However, due to the lack of a method that allows us to predict these changes, the decisions made by designers and contractors can be evaluated only after completing the investment. Therefore, it is necessary to elaborate a method to evaluate the environmental safety in regulated and maintenanced rivers. This article presents a model that allows us to predict the changes in vascular aquatic plant communities, which result from technical interference in the river bed. The model was elaborated based on the results of the study performed in 2007–2011 in natural and transformed lowland watercourses from Lower Silesia area (Poland). It takes into account the elements of the watercourse bed ecosystem, which significantly affect the magnitude of the changes in plant communities. Based on this model, it is possible to evaluate the level of ecological risk associated with the execution of maintenance and regulatory works.