The Influence Of Land Use On Plant Species Diversity In The Biosphere Area “Schwäbische Alb”, Southwest Germany

Abstract

The aim of this study was to determine the relations between the intensity of land

use and the characteristics of different habitat types within the grassland

ecosystem in the Biosphere Area “Schwäbische Alb” in Germany. Data has been

collected based on 50 examination plots (4×4 m) of the Biodiversity

Exploratories project. These plots represented different land use types and levels

of intensity which are 1) grazed, ungrazed 2) once, twice, three times mowed, 3)

fertilised, unfertilised. All vascular plants, their ground cover and several

environmental parameters (soil type, solum thickness, inclination and exposition)

were recorded. Biomass was taken (g/0.2 m²) and was examined. Data analyses

were taken from several bivariate and multivariate statistics. The results

indicated that the land use parameters grazing, mowing and fertilisation were the

most important determinants for species richness (species number/16 m²),

evenness, (Shannon) diversity, composition and biomass production. Inclination

was an important environmental factor. DCA showed an overlap between

frequently mowed meadows and mowed pastures due to the similar species

composition. Grazed pastures were clearly separated from all other samples due

to a different species composition, high species richness and a rather low

biomass production. Highest species richness and diversity and lowest biomass

were found in semi-dry grasslands. Traditional used meadows with low mowing

frequency and low or none fertilisation reached high species richness and

diversity and low to intermediate biomass production compared to all other

samples. Through raising the cutting frequency and the degree of fertilisation