Abundance and diversity of Carabidae (Coleoptera) in different farming systems

Commercial farms were examined in western Canada to assess the impact of two cropping systems (annual-grain and diversified grain-forage) and two input systems (high level and organic) on carabid beetles. Pitfall traps were used to sample beetles over 3 years (1994-1996). Results showed that five species of Carabidae dominated the 51 species captured (Bembidion quadrimaculatum (LeConte), Bembidion obscurellum (Motschulsky), Agonum placidum (Say), Amara littoralis (Mannerheim), Bembidion nitidum (Kirby)). The annual-grain system was found to support greater species diversity than the diversified grain-forage system but there was no significant difference in the mean abundance. There were no significant differences between species diversity or mean abundance in high input versus organic systems. An inventory of carabids associated with specific agricultural production systems in Saskatchewan was developed, based on data collection and evaluation by crop, pest, economic and soil scientists, which are intended to monitor long-term sustainable agricultural production systems.