Abstract:
The distribution of surface humus and large and medium-sized soil fauna in evergreen broad-leaved forests (low altitude, L), deciduous evergreen mixed forests (medium altitude, M) and deciduous broad-leaved forests (high altitude, H) was investigated and analyzed along the altitudinal belt of Lushan Mountain, the distribution characteristics of soil humus and soil animals in the vertical natural zone were investigated by using survey data. The humus characters of investigation and analysis include the thickness of each occurrence layer, the thickness of O-A transition layers and aggregates size of A-horizon and organic matter, total carbon content, total phosphorus, total nitrogen, total carbon content and pH value of A layer. Soil fauna characters included the number of biological groups, individual density and diversity index. The results showed that the surface humus of L, M and H natural zones were mainly fine humus (Mull), semi-humus (Moder) and coarse humus (Mor), respectively. A total of 2636 large and medium-sized soil fauna were identified, belonging to 24 orders in 8 classes under 3 phyla, in which the average density was 2245.23 ind m
−2. Among them, the dominant group was Prostigmata, Oribatida, Collembola, and the number of individuals in the dominant groups was 38.87%, 25.36% and 13.37% respectively. The pearson Correlation and CCA analysis showed that the individual density of soil fauna was closely related to soil nutrient content in A-horizon and the number of biological group was highly associated with the thickness of O horizon. The diversity index was closely connected not only to soil pH of A-horizon but also to soil nutrient content in A-horizon and the thickness of O-A transition layer. The overall characteristics of soil fauna distribution are that dominant groups are widely distributed in different humus groups, while the common groups were in close relation with the thickness of OH layer, but the rare groups had an intimate connection with the thickness of OL layer.