| Based on the thorough investigation,the dynamics of the arthropod communities in chestnut orchard and interaction of the Myzoxcdlis karicola Matsumura with its natural enemies were studied by means of the community analysis,multianalysis and geostatistics. The conclusions were as follows.1. The arthropod communities in chestnut orchard in east Anhui were divided into four sub-communities,which were phytophages,predators,parasitoids and neutralities. The structure and dynamics of the arthropod communities and different sub-communities were analyzed by using a number of community parameters in the chestnut orchard. The results indicated that there were 178 species of arthropod belonging to 101 families in chestnut orchard. The relative abundance of phytophages was 0.93295,the value during April to October was 0.79026-0.96978;in November was the lowest,0.1509. The relative abundance of predators was 0.O4062,the value during April to October was 0.02015-0.19537;in November was the most high,0.84091. The dominant concentration of arthropod communities was 0.25636;it showed that the dominant concentration of sub-communities was phytophages > predators > parasitoids.2. The diversities and evenness of phytophages sub-communities was in consistent with the total community;the tendency during April to November was from low to high,to low,and then,to high again. The diversity and evenness of predator sub-community was mainly steady,but occasionally reduced. The results of diversities and evenness calculated by different methods were not the same. The diversity was a function of species richness,evenness and numbers;the main component affecting diversity was species evenness,which accounted for 53.683% of the variation in diversity. The arthropod communities in chestnut orchard went through a succession that apparently changed from development to prosperity,then to depression. The best temporal partitions in the arthropod total communities were 4.18-5.21,6.23,7.20-8.22,and 10.25-11.17. The result of the best temporal partitions of phytophages sub-community was the same as the total community. The result of the predators sub-community was 4.18-5.21,6.23 and 720-11.17.3. The temporal niche breadth and overlap of Myzoxallis karicola Matsumura and its natural enemies,the vertical spatial breadth and overlap of them in different stage of chestnut growth were analyzed. Myzoxallis karicola Matsumura appeared in all stages of chestnut growth,but its population fluctuation showed two peaks,so mat its niche breadth index was middle. The niche breadth of Coccinellidae natural enemies,especially Chilocorus kuwanae Silvestri was higher,its niche overlap with Myzoxallis karicola Matsumura was also high. The niche breadth of spider natural enemies differed in different stages. The fuzzy neartude of Chrysopidae and Coccinellidae with Myzoxallis karicola Matsumura were high. During all stages of chestnut growth,Chrysopidae and Coccinellidae could follow simultaneously with Myzoxallis karicola Matsumura. The synchronous effect was high between Agelenidae and Myzoxallis karicola Matsumura.4. Investigations on the spatial construction and distribution of Myzoxallis karicola Matsumura and its natural enemies,Chilocorus hnvanae Silvestri,at different period were conducted with geostatisticed. The results indicated that the semivariogram of M karicola Matsumura was described by spherical model from 18 April to 20 July and 23 September,showing an aggregated spatial arrangement,the ranges of spatial dependence were 5.93m,12.10m,10.83m,10.25m and 15.00m respectively,the degrees of spatial dependence were 86.83%,37.24%,58.72%,65.18% and 86.91% respectively. But in some special period,for example,on 22 August and 25 October,the semivariogram of M karicola Matsumura was depicted as linear models,showing random or even arrangement As for Chilocorus kuwanae Silvestri,the models were all spherical ones from 18 April to 25 October,showing an aggregated spatial arrangement,the ranges of spatial dependence were 6.61m~14.94m,the degrees of spat...
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