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对降水量小于200mm的沙坡头无灌溉条件下人工植被固沙区土壤有机碳和全氮含量变异进行研究。结果表明,流沙在固定过程中,人工植被固沙体系的营建改善了成土环境,促进了生物地球化学循环,使土壤碳、氮的含量和分布规律发生了变化:①固沙区土壤有机碳和全氮含量及C／N均高于流沙区,随土层深度增加土壤有机碳和全氮含量呈逐渐降低趋势,而C／N呈逐渐升高趋势;②不同年限固沙区间土壤有机碳、全氮含量及C／N变异小于土层垂直方向的变异;③不同年限固沙区土层垂直方向土壤有机碳和全氮含量及C／N变异较大,变异主要存在于结皮层及其下土层(0～5cm);④流沙区土壤碳、氮含量及C／N低于固沙区,而且在土层垂直方向上基本无变异。
The variation of soil organic carbon and total nitrogen in artificial sandstone-fixing desertification area under the condition of non-irrigated area with less than 200 mm of precipitation was studied. The results showed that the artificial sand fixation system improved the soil forming environment and promoted the biogeochemical cycle in the fixed process of sand flow, which changed the content and distribution of soil carbon and nitrogen: (1) Soil organic carbon and total The content of nitrogen and C / N were higher than that of quicksand area. With the increase of soil depth, the contents of soil organic carbon and total nitrogen decreased gradually, while the C / N increased gradually. ②The contents of soil organic carbon and total nitrogen The content and C / N variation were less than those in the vertical direction of the soil layer. (3) The variation of soil organic carbon and total nitrogen and C / N in the vertical direction of the soil layer in the different years of sand fixation were large. The variation mainly existed in the crust and its lower soil layer 0 ~ 5cm) .④The soil carbon and nitrogen contents and C / N in the runoff area were lower than those in the sand fixation area, but there was no variation in the vertical direction of the soil layer.