Research On Sulfur Specification And Transformation Of Purple Soil Under Different Fertilizing Measures

As one of the most important and essential elements for crop growth, S plays an important role in agricultural production. In recent years, with the reduction of Sulphur dioxide emissions from various industrial sources, the increasing use of highanalysis-low-S containing fertilizers and high yielding plant varieties, Sulphur deficiency was recognized as a constraint to crop production. In this research, a field experiment established in 1991 on purple soil from Long-term Monitoring Network of Purple Soil were chosen to investigate the effects of long-term application fertilization treatments on sulfur(S) with different forms, aryl sulfatase activity and the population of SRB. The results were listed as follows:(1) The application of mineral and manure fertilizer increased the input of S. The treatment with high amounts of mineral and manures contained higher contents of total S and water-soluble S. The treatment of mineral and manures contained higher contents of adsorbed S.(2) The treatment of mineral and manures contained higher contents of C-bonded S and ester sulfate compared with CK, specifically 1.5NPK+M1>NPK+M1>NPK+M2. The contents of C-bonded S are significantly correlated with total organic C(P<0.05). The main form of organic S in soil are UO-S and it correlated with total S(P<0.01).(3) The aryl sulfatase activity is significantly correlated with population of SRB in soil. The application of mineral and manure increased aryl sulfatase activity and the population of SRB in top soil.(4) The application of mineral and manure fertilizer treatments transformed high level of water-soluble S under anaerobic incubation with light. The velocity rate reached its maximum in 15-18 d and remained more content of water soluble S than other treatments after 30 d.