Abstract:

【Objective】 Evolution of the soil chemical properties in paddy field under long-term application of sulfur-containing and chloride-containing fertilizers was investigated. Its purpose was to provide a theoretical basis for fertilization and sustainable use of soil. 【Method】 Historical soil samples from 33 years long-term field experiment were analyzed. 【Result】The results showed that the soil pH all decreased with years in all treatments of SO42-, Cl-+SO42-and Cl-. The annual decreasing rate of the soil pH reached 0.028 under the treatment of SO42- and that decreased with years significantly. The contents of soil organic matter, total nitrogen, total phosphorus and Olsen-P all increased with years. The annual increasing rates were 0.31, 0.17 and 0.15 g•kg-1 for soil organic matter, 10.6, 3.0 and 11.2 mg•kg-1 for total nitrogen, 22.9, 21.0 and 4.8 mg•kg-1 for total phosphorus, and 1.42, 1.14 and 0.58 mg•kg-1 for Olsen-P in the treatments of SO42-, Cl-+SO42- and Cl-, respectively. Total potassium and exchangeable potassium content in the soil were kept balance under different treatments. 【Conclusion】 A clear advantage in accumulation of the soil organic matter and total phosphorus, and in activation of the soil Olsen-P was observed under long-term application of sulfur-containing fertilizers. Therefore, sulfur-containing fertilizers should be paid more attention to prevent soil acidification in the hilly area of southern China.

Key words: paddy field')">paddy field, long-term fertilization, sulfur-containing fertilizers, chloride-containing fertilizers, soil chemical properties, evolution