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土壤交换性阳离子的组成与土壤物理和化学性质密切联系,因而也是土壤改良和合理利用以及土壤类型划分的重要依据之一。目前非石灰性土壤已经有了包括测定交换量和各主要阳离子在内的成熟的系统分析方法。对石灰性土壤来讲,首先要考虑的是交换性钠,因为它标志着土壤的碱化程度。但是土壤碱化程度的划分不是按其绝对含量,而是按其相对含量,也就是按交换性钠占交换性阳离子总量的比例来确定的。此外,交换性镁对土壤碱化及其理化性状的影响也很受人们所重视,同时常需要分析土壤各主要交换性阳离子和交换量。
The composition of soil exchangeable cations is closely related to the physical and chemical properties of soils and thus is also one of the important bases for soil improvement and rational utilization and for the classification of soil types. At present, non-calcareous soils already have established systematic methods of analysis, including the determination of the amount of exchange and the major cations. For calcareous soil, the first consideration is exchangeable sodium because it marks the degree of alkalization of the soil. But the degree of soil alkalization is not divided by its absolute content, but by its relative content, that is, according to exchangeable sodium accounted for the proportion of exchangeable cations to determine. In addition, exchangeable magnesium on soil alkalization and its physical and chemical properties are also very much attention, at the same time often need to analyze the major exchangeable soil cation exchange capacity.