Abstract: In this study, the energy crop effects of species types (cassava Manihot esculenta and sugarcane Saccharum officinarum), cropping patterns (intercropping and monoculture), and terrain selection (sloping land and flat land) on the soil fauna and corresponding soil environment quality were examined, taking the flat arable land planting with cassava as a reference for the cultivated land continuing operations in Wuming County, Guangxi Province. Planting sugarcane led to the significant decrease in the abundance and diversity of soil fauna and the corresponding soil biological quality, with the decrement of the soil biological quality reached 53% (P=0.032). Intercropping peanut (Arachis hypogaea) had no obvious effects on the abundance and diversity of soil fauna and the soil biological quality, but the biodiversity increased significantly, as compared to cassava monoculture. Terrain selection had obvious effects on the soil fauna. On sloping fields, the abundance of soil fauna, biodiversity, and corresponding biological quality were generally decreased. These results indicated that cassava could be more suitable for long-term cultivation than sugarcane. The negative impacts of cassava cultivation on the soil biodiversity and soil quality could be buffered through the optimization of cropping pattern and terrain selection. It could be predicted that cassava would be selected as a long-term prior energy crop in Guanxi.

Key words: Zostera marina, morphological parameter, morphology adaptability, reproductive strategy.