同步辐射中能X射线近边吸收谱方法研究不同施肥制度对土壤中硫形态的影响

土壤中硫是继氮、磷、钾之后的第四位重要的营养元素,它的形态转化对农作物生长等有很大的影响。本文利用同步辐射中能X射线近边吸收谱(XANES)方法研究用于长期定位试验的不同施肥制度的潮土,利用实验谱拟合出土壤中硫的不同价态的百分含量。结果表明,还原态,中间价态和高氧化态的硫在土壤中都存在,但主要以高氧化态的形式存在;不同的施肥制度对土壤全硫的含量也有不同的影响,不同氧化态的硫的比例和含量也都发生了变化。

Sulfur speciation in soil under long-term fertilization by XANES

Sulfur is considered to be the forth important nutrient element, and its transformation greatly affects the growth of plants. In this paper, sulfur speciation in different soils is researched. Effects of long-term fertilization in different combinations were studied by sulfur K-edge XANES of the soil samples, and the proportions of S at differ-ent oxidation states were determined by fitting the sulfur K-edge XANES spectra. The results indicate that the soil samples contained all kinds of sulfur states, i.e. the most reduced S, intermediate S and highly oxidized S, with the highly oxidized S being the largest proportion. The contents of total sulfur are different in soils in different long-term fertilizer experiment, and both the rates and contents of different oxidation states change.