黑垆土长期轮作培肥土壤有机质氧化稳定性的研究

以黄土旱塬长期定位试验为研究材料,分析了不同轮作与施肥对土壤有机质的含量及氧化稳定性的影响。在轮作系统引入豆科作物后,有机碳和易氧化有机碳含量增加,且豆科作物茬口的氧化稳定性低于小麦茬口,利于养分的释放和肥力的持续供给。培肥对氧化稳定性的影响表现在:长期不施肥或单施化肥氧化稳定性升高,促进了土壤有机质的老化。有机肥或有机无机配施能明显提高易氧化有机碳的含量,降低有机质的氧化稳定性,提高土壤肥力水平。苜蓿连作土壤剖面Kos的变化显示:随土层深度的增加,氧化稳定性也逐渐增加。

Study of long-term rotation and fertilizations on black loessal soilon the oxidation stability of soil organic matter

Soil samples from the long-time experiment in dry highland of Loess Plateau were used for analysising the effect of fertilization and rotation on the contents and the oxidation stability of soil organic matter. The results showed that leguminous could increase the contents of soil readily oxidizable organic matter and total organic matter, at the same time, the oxidation stability of leguminous was lower than that of wheat, which was benefit to reserve and supply of soil nutrient. The oxidation stability of soil organic matter increased under long-time no fertilization or one chemical fertilizer application, on the country, the contents of soil readily oxidizable organic matter and the level of fertilizer increased under organic and fertilizer, decreasing the oxidation stability. The soil oxidation stability in profile increased with the depth of soil layers on continuous alfalfa cropping.