Motivation

© Charles Erdman/Trout Unlimited

The resilience of landscapes and ecosystems to climate change depends largely on how they react to an extremely fluctuating water supply. The border region between Saxony and the Czech Republic is particularly affected by environmental risks due to flooding and drought (frequent floods, forest dieback, forest fires). Beaver activity can achieve a balancing of the water balance, an increase in biodiversity and thus an increase in regional climate resilience. In addition to the positive effects (e.g. watercourse renaturation, increased retention), however, negative effects (e.g. undermining, unwanted flooding) must also be taken into account, leading to increasing criticism of the reintroduction and population growth of beavers, which were almost extinct in many regions of Europe at the end of the 19th century.
A special characteristic of the beaver is its endeavour to create a favorable habitat by building dams in watercourses. This significantly alters the hydraulic, hydrological and ecological conditions both above and below the dams. Whether and under what conditions these changes are significant for regional surface and groundwater conditions has not yet been sufficiently clarified. As a result, both the municipalities and the water and environmental authorities lack a sound basis for decision-making and argumentation as to whether beaver dams should be left in the watercourse or whether adaptation measures are necessary.