三种温带森林大型土壤动物群落结构的时空动态

Abstract

Soil macro-faunas are important decomposers in ecosystem and play a significant role in nutrient cycling and energy flow. In Maoer Mountain,the soil macro-faunas were investigated in three typical forest types(Korean pine plantation forest,Hard-wood forest and Mongolian oak forest). Our object was to explore the community structure,spatial and temporal dynamic of soil macro-fauna,and its impact factors in temperate forest. Soil samples were collected from the litter layer and the soil layers at depth of 0—10 cm and 10—20 cm. Sampling was carried out continuously from May to October in 2012. A total of 3604 individuals,belonging to 3 Phyla,6 Classes,17 Orders and 50 families were extracted and identified. Among them,the Lumbricidae,Enchytraeidae and Lithobiomorpha were the dominant communities. The results showed that:(1) for horizontal distribution,the decreasing order of individual density and biomass was Korean pine plantation,Hard-wood forest and Mongolian oak. The group number of soil macro-faunas was the largest in Hard-wood forest,and the least in Mongolian oak forest. The Shannon and richness indices of soil macro-faunas were the highest in Mongolian oak forest and the lowest in Korean pine plantation forest,but the trend in the dominance index was opposite.The evenness index was the largest in Mongolian oak forest and the least in Hard-wood forest;(2) for vertical distribution,the individual density,group number,biomass and diversity of soil macro-fauna were significantly affected by the soil layer(P0.001). The individual density distribution appeared significant surface-aggregation,and the maximum biomass of soil macro-fauna was found at depth of 0—10 cm. The group number showed a decrease trend with the increasing layer in Korean pine plantation forest and that of highest value in both Hard-wood forest and Mongolian oak forest occurred at 0—10cm depth,not the litter layer. The Shannon index decreased with the increasing soil depth,while the dominance index appeared the opposite trend;(3) the Shannon and dominance index of soil macro-fauna were significantly different among different months(P0.01). Individual density and group number were higher in May and September than other months,and biomass of soil macro-fauna was the largest in September;(4) the correlation analysis showed that the individual density,group number and biomass of the soil macro-fauna were positively correlated with total organic carbon(P0.05),there was the significantly negative correlation between the Shannon index and soil bulk density(P0.01). It can be conclude that there was obviously spatial and temporal heterogeneity in soil macro-fauna community structure and the total organic carbon was one of the important impact factors.