Selected elements of vascular flora structure under long-term flood conditions in the Warta Mouth National Park, Poland

摘要

Botanists are interested in river valleys because of their continuous transformations. The temporal and spatial dynamics of river ecosystems offer excellent opportunities for the observation of changes in flora and vegetation. Although the majority of European lowland river valleys are under the strong influence of long-term human activity, knowledge about the reaction of flora to hydrological regime changes is limited. The mouth of the Warta river valley is a very good model environment for conducting these kinds of observations. Even though its landscape has been changed by regulation work, some habitats are still close to natural. However, humans use much of the land as semi-natural meadows and pastures. The study was conducted in two hydrologically distinct areas. These areas were created over 200 years ago, during land melioration of the former inland delta covered by riparian forests, willow shrubs and rushes. The first of these areas is a flood reservoir, which collects excess water. The other is a polder, which is protected by a flood embankment. In the analysis of the species richness of local flora, synecological structure and life forms spectrum were taken into consideration. The aim of this study is to reveal differences in the selected elements of vascular flora structure, which occurs in the two aforementioned hydrologically different areas.