Effect of long-term cultivation on soil arthropod community in sandy farmland.

In order to further understand the evolution of soil arthropod diversity in desert area farm land,under similar farming system and fertilizing and irrigation management measures,4 types farmland was closed as sample fields at Horqin sandy area,including no tillage,cultivated for 3 a,10 a and 20 a.Soil arthropods from different types of farmlands were collected to find out effects of long-term farming in desert area farmland on soil arthropod diversity.The results indicated that soil water content,pH,organic carbon and total nitrogen contents in farmland cultivated for 20 a were higher.Soil properties of no tillage farmland,cultivated for 3 a and 10 a were similar.In desert area,the length of cultivation had profound influence on soil environment.All together 216 soil arthropods were collected.They belonged to 3 classes and 10 items.Among them,Acarus and Collembora were superior genus;Corrodentia,Araneida,Coleoptera,and Hymenoptera were common genus.The density of soil arthropods in no tillage farmland was the highest,followed by farmlands cultivated for 10 a and 20 a.The number of individual soil arthropods in faunal cultivated for 3 a was the least.Correlation analysis indicated that soil pH at different tillage time might be the important factor for diversity distribution of soil arthropods.Initial study also showed that in desert area farmland no tillage was favorable for individual soil arthropod to survive.Short period cultivation(10 a) was not favorable for soil arthropod to settle down,but long-term cultivation(20 a) was propitious to improve and maintain soil arthropod diversity,thus facilitating the protection of soil diversity in desert area farmland and management of farmland ecosystem in Horqin sandy land.