我国几种土壤中腐殖质性质的研究

研究了几种土壤腐殖酸的基本性质,其中包括土壤的腐殖质组成,胡敏酸以及富里酸的元素组成,含氧官能团含量,光密度值与芳化度等,计算了E₄与E₄/E₆比值与上述性质的相关系数。结果表明土壤腐殖质组成和性质与其形成条件有着密切的联系,并且有一定的地带规律性。水稻土中有机质含量增加,HA/FA比值变高,其活性HA显著降低,说明水稻土有利于有机质的积累并改变了腐殖质的组成。E₄、E₄/E₆比值与元素组成,C/H比值,含氧官能团及芳化度之间的相关系数表明E₄除了与C%,O%,酚羟基-O%,醌基-O%呈极显著或显著相关外,还与C/H比值及芳化度呈极显著相关,因此E₄值可作为腐殖物质芳化度的一个指标。

STUDY ON PROPERTIES OF SOME SOIL HUMUS IN CHINA

The results of this study indicated that the composition and properties of soil humus were closely related to their formation conditions,and had zonal regularities.Data obtained showed that the composition of soil humus in virgin soils varied with different soil zones.For geographical distribution from black soil to red earth,the optical density elementary composition,C/H ratio and aromaticity of humic acids in the soils all had certain zonal regularities.According to the results mentioned above,the soil humus substances appear to tend to be simple from the north to the south.As compared with the virgin and dry farming soils,paddy soil had a higher content of organic matter and HA/FA ratio,but a lower content of active humic acid.It indicates that the hydrothermal conditions under rice planting are favourable for the aecumulation of organic matter,and change the composition of soil humus.However,the anaerobic condition of paddy soil is a factor inhibiting the decomposition and condensation of organic matter in soil,which results in the formation of humic substances with smaller molecule and low-degree of humification.Calculation of the correlation coefficients between E₄,E₄/E₆ ratio and elementary composition,C/H ratio,oxygen-containing functional groups and aromaticity show that E₄ value is not only significantly correlated with C%,O%,phenolic-OH-O%,quinone O%,but also with C/H ratio and aromaticity.It is also indicated from these results that E₄ value might be regarded as an index of aromaticity of humic acids.