绿洲盐渍土不同开垦期土壤有机碳和无机碳剖面分布特征

摘要

The profile construction of soil organic and inorganic carbon in oasissaline soil during different reclaimed period of Manas Basin in North Tianshan Mountains,Xinjiang were analyzed.The result indicated that content of the organic carbon in the reclaimed soil was higher than that in the unclaimed soil,and soil organic carbon slowly increased with the prolonging of the reclaimed time.The profile of soil inorganic car-bon of the reclaimed 20 a soil and reclaimed 50 a soil changed with a low-high-low rule;while low-high-low rule in reclaimed 30 a soil in inorganic carbon profile distribution.The density of soil organic carbon during different reclaimed period decreased with the soil depth.The density of inorganic carbon continuously in-creased;The distribution rule of organic density in corresponding horizons was follows:reclaimed 20 a soil>reclaimed 30 a soil>reclaimed 50 a soil>unreclaimed soil;The distribution rule of inorganic carbon den-sity:reclaimed 20 a soil>unreclaimed soil >reclaimed 30 a soil>reclaimed 50 a soil.%对比分析了天山北麓玛纳斯河流域不同开垦期绿洲盐渍土壤的有机碳和无机碳剖面分布规律，结果表明，已开垦土壤的有机碳含量高于未开垦土壤，随着开垦时间的延长，土壤有机碳增加趋势减缓。开垦20 a和开垦50 a土壤的无机碳在剖面呈现低-高-低-高的变化规律，开垦30 a土壤的无机碳在剖面中呈现低-高-低的变化规律。不同开垦期土壤有机碳密度随土层深度不断减少，无机碳密度不断增加；对应层位的有机碳密度分布规律为：开垦20 a土壤>开垦30 a土壤>开垦50 a土壤>未开垦土壤；无机碳密度分布规律为：开垦20 a土壤>未开垦土壤>开垦30 a土壤>开垦50 a土壤。