闽东南耕地土壤硫素平衡及有效硫丰缺状况研究

Sulphur Balance and Plentiful-lack of Soil Avaivable Sulphur in Southeast of Fujian Province

通过田间试验、土样和雨水、灌溉水采集测定,以及大气硫沉降和土壤硫淋溶流失有关数据收集,研究了闽东南耕地土壤硫素平衡与土壤有效硫丰缺状况。结果表明,早稻-晚稻轮作制和花生-甘薯轮作制每年分别需要91.86,128.67 kg/hm2硫素来满足生长需求,考虑到土壤硫的淋溶和流失以及扣除施肥带入的硫素、大气沉降和灌溉水硫的给源外,早稻-晚稻轮作制需补充22.35 kgS/hm2硫素,花生-甘薯轮作制需补充64.89 kg/hm2硫素,才能维持土壤硫素输入与输出的平衡。178个土壤样品有效硫含量测定结果表明,当前闽东南耕地土壤有效硫平均为26.2mg/kg,其中水田为22.35 mg/kg,旱地则为28.31 mg/kg,低于有效硫临界指标的土样数占总数的69.0%,有效硫含量属于中等级别的只占16.3%,说明硫已成为闽东南耕作土壤的养分限制因子之一。

It was studies sulphur balance and plentiful-lack of soil available sulphur in southeast of Fujian province by farm trials, soil sampled, rainwater and irrigation water collected and tested, and data collected about atmosphere deposition of S and leaching loss of soil S. The results showed that field experiments of main rotation including early ricelater rice rotation and peanut-sweet potato rotation needed 91.86 kg S/ha and 128.67 kg S/ha respectively to meet growth requirement, which needed to add 22.35 and 64.89 kg S/ha respectively to keep sulphur balance except for sulphur input from fertilization, atmospheric deposition and flooding water. It was studied plentiful-lack of soil available sulphur in Fujian province that indicated critical index of available sulphur in rice soil was average 23 mg/kg as well as that in dry soil was average 25 mg/kg. The results showed that average available S was 26.2 mg/kg according to 178 cultivated soil samples of farmland in the southeast of Fujian province, in which average available S of rice soil was 22.35 mg/kg as well as that in dry soil was average 28.31 mg/kg, 45.5% of the total samples was S deficient that S content was lower than 16 mg/kg,69.0% of total soil sample was S deficient or potential deficient that S content was 16 - 25 mg/kg, only 16.3% of total samples was middling, which suggested that S was one of nutrient limiting factor in the southeast of Fujian province farmland.