稻-稻-油种植制硫肥效应及硫素平衡研究

研究了稻-稻-油种植制硫肥效应及土壤硫素平衡,结果表明:不同硫肥品种在水稻上的增产效应以硫酸钾最好,硫磺次之;在油菜上以石膏最好,硫磺次之。硫素当季利用率早稻为7 5%,晚稻为10.9%,油菜为29 6%。在不施硫条件下,土壤硫素表现亏缺;在施低量硫条件下(每季作物施硫15kg/hm2)基本上可以保持土壤硫素的平衡;在施中、高量硫条件下,土壤硫素均有不同程度盈余。施用硫肥具有明显的后效,连续两年施用硫肥后,可以隔年或隔季不施。

Effect of Sulphur Fertilizer and Soil Sulphur Nutrient Balance in Rice-Rice-Rapeseed Cropping System

The effect of sulphur fertilizer and soil sulphur nutrient balance in rice-rice-rapeseed cropping system were studied, the results showed that among three sulphur fertilizer varieties, potassium sulphate had the best effect on rice yield, followed by elemental sulphur; while gypsum had the best effect on rapeseed yield, followed by elemental sulphur. Under the condition of applying sulphur fertilizer, the recovery rate of sulphur fertilizer in early rice, late rice and rapeseed was 7.5%, 10.9% and 29.6% respectively. The soil sulphur nutrient was deficient when no sulphur fertilizer was applied, while it was surplus when middle or high rate of sulphur fertilizer was applied. The balance between supply and consumption of soil sulphur nutrient could basically be kept when low rate of sulphur fertilizer (15kg/hm~2 on each crop) was applied. In addition, sulphur fertilizer application had obvious residual effect , after two years' successive sulphur application, it was not necessary for rice-rice-rapeseed cropping system to apply sulphur fertilizer in the next year.