Study On The Soil Fauna Communities Structure Of Degraded Alpine Meadows Under Restoration In The Three River Source Region

This study aims at investigating the effect of artificial restoration measures onmeso-micro soil fauna community as well as the relationship between or amongmeso-micro Soil Fauna,vegetation, the number of soil microbes, microbial biomasscarbon and soil physicochemical factors in the Three River Source Region to providescientific basis on evaluation the efficacy of the Three River Source Region ecologicalrestoration and soil quality management. Meso-micro soil fauna of alpine madows inthis region was studied to analyze its community structure under differentconditions(different established periods or successional stages). Results are asfollows:1. In the study, the number of captured meso-micro soil fauna is9305.All thesesoil fauna belongs to3Phylums10classes26orders,66families,81genera. Thedominant groups are supposed as Nemata, Acaroidea and Oiibatida(this three kindsaccount for62.84%of all);Common taxon are Enchytraeidae, Ixodidae and other11classes which account for30.96%in all; rare taxon have been proved to beEupodoidea, Phlaeothripida, Trichoceridae, and other21classes with the percentageof5.1%;Occasional groups are Giycyphagida, Atypidae, and other12classes with alowest percentage of1.1.%. Dominant groups and common groups are elementary tothe alpine meadow soil Fauna structure but diversity of this area hides behindcommon groups and occasional groups.2. In artificial grassland, with long established, the structure tends to be morecomplicated,stable and diversiform an dvice versa, with short established artificialgrassland, meso-micro soil Fauna community is not stable, biodiversity is lower thanthe natural degradation of grassland, the community is not stable.From the point ofvertical distribution.The distribution of meso-micro soil fauna showed obvioussurface aggregation phenomenon, artificial grass surface aggregation significantlythan the degraded grassland, the degradation degree of grassland surface aggregationsignificantly lighter than the "black soil beach".3. The individual number of meso-micro soil fauna trends to change from seasonto season.The order from max to min should be: Aug.> Sept.>Oct.> Apr.>May>June>July.So does the group number and the order should be July>Aug.> Oct.>June> Sept.>May.> Apr. The most active period of a year should be August.Seasonal variation trend of meso-micro soil fauna is largely affected by the dominantgroups (mainly nematodes and mites).4. Results shows that there are great difference in soil fauna community structureamong15samples: structures are moderate similar or less similar with differentestablished periods; structures also seem to be moderate similar in August, Spetemberand October while the less similar with the other months. 5. The physical and chemical properties of the soil have a different effect on soilfauna, meso-micro soil fauna number and organic matter, total nitrogen, totalpotassium, available nitrogen, phosphorus and potassium water were positivelycorrelated, and negatively correlated with total phosphorus, pH, and the available pwas significantly negative correlated (r=0.569*), meso-micro Soil Fauna groupsnumber and total nitrogen, total phosphorus, total potassium, available nitrogen,available potassium were positively correlated, and organic matter, available p, pH,negatively correlated with water, the number of soil animals, the number of taxa andavailable phosphorus and pH were negatively correlated, the total nitrogen contents ofthe seasonal change of dynamic number and meso-micro soil fauna dynamicsimilarity.Small and medium-sized the number of soil animal and the number oftaxa and aboveground biomass were significantly positively correlate（dr=0.623*）, thenumber of soil animal and hight, coverager, species number were positively correlated,and underground biomass were negative correlated, the ground vegetation restorationin degraded grassland restoration can help the increase of the meso-micro soil faunanumber and diversity. meso-micro soil fauna is negatively correlated with the numberof fungi, bacteria, and actinomycetes were positively correlated, the number of groupsof soil animals, fungi and actinomycetes were positively correlated, and negativelycorrelated with bacteria, three main microbial groups, the distribution ofactinomycetes and closely related to the distribution of meso-micro soil Fauna...