吉林省中西部平原区土壤螨类群落结构特征

Characteristics of soil mite community structures in the mid-west plain, Jilin Province

对吉林省中西部平原区进行土壤螨类群落调查,了解该区土壤螨类群落组成、分布及土地利用差异对土壤螨类群落结构的影响。共捕获土壤螨类96属16443只。研究结果显示:土壤螨类群落组成各类群空间分布的广狭与个体数量的多寡在吉林省中西部平原区未呈现出明显的一致性;中部平原区与西部平原区土壤螨类群落组成存在明显差异,气候和土壤差异是主导因素;不同土地利用类型生境螨类群落特征存在一定的差异,农业生产活动减少了土壤螨类类群数和个体密度,使螨类在土壤剖面不同土层间分布更加均匀;同时农业活动也减少了螨类的群落多样性。MGP分析能够反映人类干扰对甲螨群落结构的影响,其中MGPⅠ分析对不同土地利用条件下甲螨群落结构的季节变动更敏感。MI指数显示,农田和居民点的农业生产活动增加了中气门螨类r-选择类群的数量[动物学报51(3):401-412,2005]。

The soil mites in the mid-west plain in Jilin Province were investigated with the emphasis laid on the community structure in relation to the types of land-use i.e. farm garden, farmland, Three-North Forest Shelterbelt, natural secondary forest and natural mowing pasture. The soil mites were extracted through Tullgren extractor and were identified to the genus level with the aid of microscope. A total of 16 443 soil mite individuals was captured and fell into 96 genera. Oppia and Scutaracus were the dominant groups that account for 24.12% of the total individuals. A considerable difference in the numbers of genera and individuals existed between the natural forest and other habitats affected by agricultural practice. The mites distributed evenly in the different layers of soil profile in all the habitats affected directly by humans in both samples collected in July and September. In these habitats affected intensively by agricultural activity during sampling date, more groups and individuals were cut down, and more diversities lost. These results suggest that the types of land use affect the species richness and abundance, and human activity has an impact on the soil mite community. The characteristics of the Oribatida community structures in different habitats were analyzed by using MGP, and Mesostigmata community by MI (Maturity index) while Shannon-Wiener Index was used in analyzing the biodiversity of the mite community. The results also show that MGPⅠ proposed by Aoki is a sensitive parameter to monitor the seasonal fluctuations of Oribatida community, and MI index first used by Ruf could indicate the r-selected groups increase of Mesostigmata community fluenced by agri-activity in farm garden and farmland.