Community structure and dynamics of soil insects in a ragweed habitat

Profile sampling method, macro-group classification method, and statistical method were used to study the community structure and dynamics of soil insects in ragweeds Ambrosia artemisiifolia and A. trifida habitats. Forty-six families of soil insects (adults and larvae were separately counted) belonging to 12 orders were collected. On the level of order, the individual number of Collembola was absolutely dominant (amounting to 80.879% of the total individual number of soil insects),followed by Hymenoptera (8.765%),Coleoptera larvae (3.951%), and Diptera larvae (3.093%), while the rest orders together amounted to 3.312% of the total. Among the 46 families, three families, i.e., Onychiuridae (amounting to 32.756% of the total individual number of soil insects), Tomoceridae (18.869%), and Isotomidae (18.178%), were dominant. The number of individuals and groups of soil insects increased with the proceeding of growth season and attained the maximum value in August. Ragweeds reduced the individual number and commu