Resource and dominant population dynamics of coccinellids in agro forestry farmland in Central Hebei Province
冀中农林复合环境瓢虫资源及优势种种群动态

Most coccinellids are predators, some of which are main natural enemies in farmland. The study is on the distribution dynamics, spatial pattern and habitat selection of coccinellids in crop growing period in the agro forestry system, in central Hebei province of North China. The results show that: firstly, the forest belt, which is the main habitat of coccinellids in the early period of crop growth, is a species pool for coccinellids in crop fields; secondly, Propylea japonica is the dominant species of coccinellids in the field; thirdly, coccinellids have apparent movement among the habitats when the season changes; fourthly, the distribution of coccinellids in the early period of crop growth is uniform or random pattern, and the distribution during the middle and late periods belongs to the pattern of aggregation that is density\|dependent; fifthly, coccinellids are inclined to intercrop fields in the late period of crop growth, indicating that complex habitat will be better placed in adverse conditions.