In 2000,the species and diversity of carabids beetle were investigated by pitfall trap in 14 land-use treatments of Dongbeiwang agroecosystem in Beijing.The treatments included woodlots,field margins,wheat/corn fields and vegetable fields with different cultivation measures.Analysis of variance (ANOVA) showed that the irragation,fertilization and straws have no effect on the diversity of carabid community;the number of species and individual number of carabid community in the woodlots,field margins were higher than these in the fields;the field margins had positive effect on the diversity and richness of carabid community in their adjacent field;moderation disturbance was beneficial for higher individual number of carabid community.It is concluded that field margin are necessary to maintain a diverse predatory carabid community in agroecosystem.
