Vegetation changes at 'Fundu Mare Island' in the Inner Danube Delta near Br?ila (Romania)

摘要

The Lower Danube River System has been heavily affected by human activities. Fundu Mate Island in the Natural Park Small Wetland of Br?ila (Romania) is one of few islands in a nearly natural state and an important nature protection area. About 50% of the area is covered by aquatic and semi-aquatic habitats. The corresponding lakes are usually flooded in spring and their water level reduces during the subsequent months depending on the water level in the Danube. During the last few years a massive willow encroachment has been observed in some formerly open habitats. In the present paper, we report on-going vegetation changes by comparing nature types that have been mapped earlier with recent observations and discuss hydrological and hydro-dynamical factors that may have affected the development. The results suggest that changes in the flow regime of the Danube during the growing season play an important role for the vegetation changes at Fundu Mare Island, together with other factors.