Composition and diversity of spring-active carabid beetle assemblages in relation to soil management in organic wheat fields in Denmark

Summary

Patterns in spring-active carabid assemblages were described in relation to four organic soil management regimes (no soil nutrient addition, undersowing, animal manure, undersowing + manure) in two areas of Denmark. On the island of Zealand, the Flakkebjerg study area had 22 species, 3-10 species/trap, and the species rank of these was the same for all treatments. The dominant species were Pterostichus melanarius, Agonum dorsale, Harpalus rufipes and Calathus fuscipes. At Foulum, Jutland, there were 46 species, 12-15 species/ trap, dominated by P. versicolor, P. melanarius, A. dorsale and Nebria brevicollis. Their rank, however, was not the same for all treatments. There were remarkable differences in the carabid assemblages of the two sites, and manure addition modified the assemblages, more pronouncedly so in the poorer-soil Flakkebjerg site. However, we did not detect clear effects of the studied treatments on carabid species richness, overall abundance or Pterostichus melanarius alone.