Soil quality has emerged as the central concept for examining and integrating relationships and functions among various biological, chemical and physical parameters of soils. Soil quality is important in the context of sustainable land use and management. Paddy soil is anthropic hydromorphic soil, and its evolution and formation are affected greatly by cultivations, irrigation and fertilization. Taihu Lake region is the major distribution area of Chinese paddy soil resource. However, due to irrational irri...