Effects of Different Habitats of Eupatorium adenophorum Spreng on the Biodiversity Arthropods

The composition and structure of arthropod communities at three different habitats with E.adenophorum Spreng distribution,i.e.wastelands,forests and intervening area between farms and forests,were investigated.The results showed that the numbers of individuals and species of arthropods in the waste land were significantly higher than those in the forests and intervening area between farms and forests.The average number of arthropod individuals in the intervening area between farms and forests was greater than that in the forests,but the average number of arthropod species was similar.The distribution of arthropods in waste land with E.adenophorum Spreng was characterized by predominance of phytophagous insects,which accounted for nearly two thirds of the total numbers of arthropods.In contrast,the distribution ratio of natural enemies and pests was relatively balanced in forests and intervening area between farms and forests covering with E.adenophorum Spreng.The numbers of species and individuals of natural enemies in waste land were smaller than those in the forests and intervening area between farms and forests though there were a large number of phytophagous insects in it.In the forests and intervening area between farms and forests,there were fewer distributing factors in the closed niches and,therefore,greater stability existed in species of phytophagous insects,resulting in a relative balance of natural enemies and pests.