武汉市蔡甸区耕层土壤中植物营养元素有效量和有效度研究

Study on Effective Amount and Availability of Plant Nutrient Elements in Topsoil of Caidian District of Wuhan City

对武汉市蔡甸区70件典型耕层土壤样品研究表明,土壤地质单元、土壤类型及其有机质含量、酸碱度、CEC等理化性质对耕层土壤植物营养元素赋存形态、有效量及有效度有重要影响。耕层土壤中N、P、Ca、Mg、Mo等元素全量是其有效量的重要影响控制因素,有机质增加有利于P、K、Ca、B、Zn等元素的活化,提高其生物有效量。土壤酸碱度对P、Ca、Mg、Fe、Mn、B、Zn和Si有效度有显著影响,该地区土壤酸性越强,P、Ca、Mg、Fe、Mn、B、Zn等元素的有效度越大;土壤碱性越强,Si元素的有效度越大。该地区Ca、B、Mo、Si等元素的有效度与CEC呈正相关,耕层土壤CEC越大,Ca、B、Mo、Si等元素的有效度越大。比较了几种不同地层成因土壤中植物营养元素有效度的高低,在不同土壤类型耕层土壤中P、K、Mg、Fe、Mn、Zn、Si元素的有效量和有效度从大到小依次为水稻土>潮土>草甸土,N元素的有效度从大到小的顺序为潮土>草甸土>水稻土。

The study ol 70 typical topsoil samples in Caidian district ol Wuhan city shows that the soil geological unit, soil type and its organic matter content, pH,CEC and other physical and chemical properties have important influence on the nutrient speciation,eflective amount and availability ol topsoil nutrient elements. The total amount ol N, P, Ca,Mg and Mo in the topsoil is an important controlling factor ol its effective quantity;the increase ol organic matter is beneficial to the activation ol P, K, Ca, B,Zn and other elements, and improves its bioavailability. Soil pH has a significant effect on the availability ol P, Ca, Mg, Fe, Mn, B,Zn and Si. The stronger soil acidity in this area, the greater the availability ol P, Ca, Mg, Fe, Mn, B,Zn and other elements; the stronger the soil alkalinity, the greater the validity ol the Si element is. The validity ol Ca, B, Mo,Si and other elements in the area is positively correlated with CEC,and the greater the CEC ol top-soil ,the more effective the elements such as Ca, B,Mo and Si are. The availability ol plant nutrient elements in different formation soils is compared. In different soil types, the effective quantity and availability ol P, K, Mg, Fe, Mn,Zn and Si in paddy soil are as follows ： paddy soil 〉 moisture soil 〉 meadow soil,and the order ol the effective degree ol N element is：moisture soil 〉 meadow soil 〉 paddy soil.