不同种植年限茶园土壤有机无机复合状况及有机碳分布特征

Soil Organic-mineral Complex Status and Distribution of Organic Carbon in Tea Gardens of Different Planting-year

通过不同种植年限茶园土壤有机无机复合状况以及有机碳的分布变化特征的研究,结果表明,植茶条件下,土壤有机碳含量、重组有机碳含量以及土壤有机无机复合量均高于非茶园对照土壤,并且随着植茶年限的增加而增加。土壤中轻组有机碳增加幅度明显大于重组有机碳,原土复合度下降。随着植茶年限的增加,茶园土壤〉50μm级复合体含量减少,〈2μm复合体含量增加,但茶园土壤有机无机复合体组成仍以〉50μm复合体为主,10-50μm复合体次之,〈2μm复合体含量最低。茶园土壤各粒级复合体有机碳含量均随植茶年限有不同程度增加,其中〈2μm复合体固持的有机碳含量最高,其余粒级中有机碳含量随着粒径变粗而下降。有机碳在各粒级复合体中的分布以及各粒级复合体有机碳占土壤总碳量的比例均表现出2-10μm复合体〉小于2μm复合体〉大于50μm复合体〉10-50μm复合体的趋势。

The soil organic-mineral complex status and distribution of organic carbon in tea garden of different planting-year were studied. The results showed that the content of soil organic carbon,content of heavy soil organic carbon and soil organic-mineral complex quality were all higher than these of control, and they were increasing obviously with planting-year increasing. The growth rate of light organic carbon was more than the growth rate of heavy organic carbon, so that the original soil complex degree was decreased. Following the increment of tea planting-year, the content of 〉50μm organic-mineral complex was decreased, the con- tent of 〈2 μm organic-mineral complex was increased. But the 〉50 μm organic-mineral complex content was still the most in organic-mineral complex components of tea garden soil, and the next was the 10-50 μm organic-mineral complex content, 〈2 μm organic-mineral complex content was the lest. The organic carbon content in each particle diameter of organic-mineral complex was increased in different degree as the planting-year increased. The 〈2μm organic-mineral complex hold most of the organic carbon. The coarser diameter organic-mineral complex, the less organic carbon it held. The trend of distribution of organic carbon content in each organic-mineral complex and the variation of percentage of organic carbon content in each organic-mineral complex to that in soil was 2- 10 μm 〉 less than 2 μm 〉 more than 50 μm〉10-50μm