Nature management experiments in a derelict reedmarsh. I: Effects of winter cutting

Abstract

Lowering of the summer water table, eutrophication and dereliction have caused severe ruderalisation of the reedmarsh in the important Belgian wetland site of the Blankaart. The reed vegetation has become totally overgrown by competitive species such as Urtica dioica, Calystegia sepium and Calamagrostis canescens. Management experiments conducted from 1978 to 1986 have shown that a regime of annual winter cutting can substantially reduce the ruderal and nitrophilous character of the vegetation and increase species diversity. The process is mostly linked to the correlated effects of litter removal. The changes in the vegetation are influenced by the position in the zonation/succession. It is argued that, for complete restoration of the vegetation, efforts should be made to raise the summer water table and to stop eutrophication and silting of the pond.