Effects of the frequency of grassland utilisation on the composition of vegetation in different grasslands

Abstract

More than 11% of the area of Hungary (1.02 million ha) is under grassland management. A significant proportion of this area is occupied by extensively used fields where fodder is grown. Extensive grassland management does not necessarily exclude multiple harvests within one season. In our experiments, we tested the effect of cutting frequency on the species composition of grassland vegetation.Utilisation frequencies (2, 3, 4 cuttings annually) were simulated by the same method at two sites, without fertiliser applications. The utilisation frequency of 2 cuttings/year was represented by a late first cutting (third decade of June) and an autumn cutting. The utilisation frequency of 3 cuttings/year was represented by vegetation surveys performed in the third decade of May, at the end of July and at the beginning of October. The utilisation frequency of 4 cuttings/year meant surveys in May, at the end of June, the end of July and at the beginning of October.In Mende, on a planted, wet meadow, surveys on vegetation composition mostly yielded less than 10 species. In Bösztör, on a dry, natural pasture, the number of identified species varied between 35-40.From the relative ecological indicators (BORHIDI 1993), the distributions of relative temperature demand (TB), relative nitrogen demand (NB) and social behaviour types (SBT) were analysed.According to the results of the examined 2 years, we may conclude that from the 3 different utilisation frequencies, the treatment with 3 cuttings/year had the most significant beneficial effect on maintaining or establishing a near-natural vegetation. Further research is needed to confirm long time impacts.