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Exploring the distribution characteristics of soil sulfur under different environments and its relationship with environmental factors is important for the comprehensive and accurate assessment of soil sulfur status and the soil sulfur cycle in Chongqing farmlands. In this study, we characterized the relationship of total sulfur in Chongqing's farmland soils with soil depth, soil type, topography, land use pattern, soil pH and organic matter using field investigations and indoor analysis. We found that the total sulfur content of surface soil was an average of 262 mg·kg-1, which was the average level of soil sulfur in China. It was higher than the critical value of crop sulfur deficiency of 150 mg·kg-1. In a horizontal direction, the total sulfur content of west and northeast Chongqing was greater than that of the southeast and the middle of Chongqing. In a vertical direction, sulfur was a decreasing feature from top to bottom. The sulfur content reached the highest levels in yellow brown soil and the lowest levels in tidal soil. Under different terrain, the total sulfur content was the highest in the middle mountains, and the lowest in the terraces. In terms of different land use modes, the total sulfur content was highest in uncultivated agricultural land and lowest in dry land. There was a significant negative correlation (PP

A plot experiment was performed to investigate the effects of desulfurized gypsum on heavy metal(Cd, Pb, Zn, Cu) accumulation in soil, speciation, rice absorption and redistribution in purple paddy soil. The results showed that after desulfurated gypsum application, the total amount of Pb in soil increased significantly by 14.00%~68.77%(P-2 desulfurized gypsum application, the total amount of Cd in soil was not significantly different from that of control. With over 4 t·hm-2 application, the total amount of Cd increased significantly by 16.28%~19.94% compared with that of control(PP-2. The contents of Cd and Pb in paddy soils increased, while the contents of Zn and Cu showed no change. The form of Cd and Pb varied to stable state. Cd, Pb, Zn, Cu contents decreased to varying degrees.