Study On Dynamics Of Soil Fauna Community Of Fixed Sand Dune In The Western Jilin Sandy Land

The sandy land of the western Jilin has the best natural and socio-economic conditions indesert regions of China. But in recent decades, the area is subjected to strong interference andpeople concerns over its future. In this article, five slope positions of fixed sand dune in sandyland of the western Jilin Province that are the middle of south-facing slope, the base ofsouth-facing slope, the top of slope, the middle of north-facing slope, the base of north-facingslope were selected for study on the community characteristics, such as the composition ofsoil fauna community, the diversity dynamics and correlations between soil animals andecological factors. This study is aim at providing the basia of soil fauna for ecosystemrehabilitation and rational use of natural resources.The characteristics of soil fauna community of5habitats, were studied in April, July,October2010. The results showed that we obtained49groups, belonging to2phylas,4classes,16orders and42families. The dominant groups are Oribatida and Actinedida. Andthe common groups are Gamasida, Formicidae, Hypogastruridae, Pseudachorutinae,Psocoptera，Entomobryidae. The both account for92.16%. The remaining41groups are raregroups, accounted for7.84%.Soil moisture and temperature are the main factors of seasonal changes of soil fauna.Due to the different lifehabits of meso-micro soil fauna and soil macro-fauna, there aredifferences in their density and group seasonal variation. DIC index of the base is highest, thetop’s lowest. Moreover, the indexes of south-facing slope are higher than north-facing slope atthe same position. So the habitat of the base is most suitable for live and following is themiddle of slope. And more soil fauna like living in the south-facing slope. But the results ofOne-Way-ANOVA show us that characteristics of communities in5habitats had nosignificant differences. The similarity index of soil fauna communities in the five slopepositions is high. Varing with the season, soil fauna communities have the different levels ofsimilarity in different slope positions. Similarity index is higher in July. The base ofsouth-facing slope, the middle of north-facing slope and the base of north-facing slope reachextremely similar level.Due to the maximum limiting factor changes, vertical distribution of soil animals isdifferent in April, July, October2010. In April, both fauna groups and individuals weredecreasing with the depth of soil layers increasing. In July, due to the differe nt response ofmeso-micro soil fauna and soil macrofauna to soil moisture, vertical distribution of density isdifferent. In October, soil temperature is the main ecological conditions of soil fauna distribution. Because of the different solar radiation, the vertical distribution of soil faunacommunity is different.The results of Pearson correlation show us that, the groups and density of soil faunashowed a positive correlation with the soil total nitrogen, soil total phosphorus, soil organicmatter content, has less relationship with soil pH and soil moisture.