Profile distribution characteristics of soil fertility properties under different land use patterns in Zhongshan city

Understanding soil fertility status under different land use patterns and finding out limiting factors affecting soil fertility are of great importance for regional soil management and rational soil fertilization. Soil under different land use patterns including paddy field, vegetable field and woodland in Zhongshan city were investigated, soil particle composition, pH, organic matter, N, P, K, cation exchange capacity (CEC) in different soil horizons were analyzed, soil fertility in soil profile and plough/surface horizon were assessed in this paper. The results indicated that clay and silt were high in soil of paddy and vegetable fields, and sand and clay were high in soil of woodland, soil particle composition closely related with parent materials. Soil in plough layer of paddy and vegetable fields had acidification tendency and soil with a sulfic horizon had strong acid. The CEC was the lowest in woodland soil, and was higher in soil of paddy and vegetable fields, human management and parent materials influenced soil CEC. Soil organic matter, N, P decreased with the increase of soil depths, soil available P in plough horizon of vegetable field was very abundant, and soil available N, P and K in woodland were the lowest. Soil organic matter, N, P contents in plough (surface) layer were affected by land uses patterns, and K content was affected by parent materials. Soil management suggestions were put forward according to soil fertility properties in Zhongshan city.