Classification and prediction of grassland habitats using ground beetles (Coleoptera, Carabidae)

Abstract

Ground beetle species assemblages were sampled by pitfall trapping from 69 grassland sites in north-east England. A TWINSPAN classification, based on the percentage occurrence of each species in the total catch from each site, identified 10 habitat groups within grasslands. DECORANA ordination was used to examine the relationships between sites. Positions of sites along the first two axes of the ordination were most clearly related to soil characteristics. The third axis was associated with intensity of management. Data from replicated sites fitted well into the same habitat groups. Discriminant analysis showed that habitat groups could be separated on the basis of site management, soil water, soil bulk density and altitude. 62% of sites were assigned to the correct habitat group on a basis of these environmental factors. Seven of 10 new sites were classified into identical habitat groups by a method based on ordination analysis using their ground beetle fauna and by discriminant functions derived from analysis of environmental factors. These results should enable the ground beetle fauna of further sites to be assessed and used quantitatively as indicators of environmental quality and change.