通过化学分析方法研究澧阳平原杉龙岗古水稻土和现代水稻土有机无机复合度及结合态腐殖质的组成及空间分布特征.结果表明:随剖面深度的加深有机无机复合量减少,复合度则相反,且埋藏古水稻土复合度>现代耕作土复合度.古水稻土腐殖质结合形态以松结态为主,紧结态其次,稳结态最少,平均含量分别为12.75、4.07和0.42 g/kg,且埋藏古水稻土含量>现代耕作土含量.从剖面空间分布上看,各结合态腐殖质含量变化幅度较大,现代耕作土松结合态含量呈先下降后上升趋势,稳结合态呈下降趋势,紧结合态呈下降后平稳趋势;埋藏古水稻土松结合态含量呈下降趋势,稳结合态缓慢上升趋势,紧结合态呈先下降后上升趋势.%The organic mineral complex degree, humus combined forms and its spatial distribution were studied with the method of sampling outdoor and analytic determination in buried ancient paddy soil of Liyang Plain. The results showed that the amount of organic mineral complex decreased with increase of the depth, however the inverse results was observed on the organic mineral complex degree, while the organic mineral complex degree of buried ancient paddy soil was greater than that of the modern cultivated soil. The loose combined humus was main in ancient paddy soil, the second was tight combined humus, thus was stably combined humus, their content were by 12.75, 4.07 and 0.42 g, respectively, while the content of buried ancient paddy soil was higher than that of the modern cultivated soil. The change of the different combined forms humus content was greater in ancient paddy soil at spatial distribution, the content of loose combined humus decreased with increase the depth in soil profile, however that of the stably combined humus gradually raised, while the trend of the first decline then rise was recorded in tight combined humus in the buried ancient paddy soil. The content of the loose combined humus indicated the trend of first rise and then increased, the stably combined humus gradually decreased, and the tight combined humus showed the change of first downward after the steady in the modern cultivated soil.
展开▼
