弃耕农田土壤分形特征研究—以内蒙古自治区伊金霍洛旗为例

Research on soil fractal feature of abandoned farmland- A case study from Yijinhuoluo County．Inner Mongolia Autonomous Region

摘要: 对内蒙古自治区伊金霍洛旗不同弃耕年限农地土壤颗粒分维数的变化特征研究结果表明，土壤细颗粒含量越少，土壤分维数越低，表征农田沙漠化程度越高。土壤分维数与各粒级颗粒组分间的关系差异较大，分维数与<0.025mm组分的相关关系最大，<0.025mm粒径颗粒组分是农田土壤沙化的重要指示性粒径。土壤有机质和N含量与土壤分维数成指数关系，表明分维数可作为表征农田沙化演变中土壤结构和养分状况以及沙化程度，评价土壤沙化演变的综合性定量指标之一。

Abstract: The changes of soil granularity and its fractal features of the abandoned land in Yijinhuoluo County，Inner Mongolia Autonomous Region in different years were studied．The results show that the soil with less fine particles has less fractal dimension and vice versa．The particle size less than 0．025mm has obvious exponential relation with fractal dimension，reflecting the degree of the land esertification．There also exist remarkable relations among the organic matter，nitrogen of the soil and fractal dimension．Therefore，the soil fractal dimens ion can be used aS an impo rtant and quantitative index indicating the degree of the land desertification and evaluating soil deterioration．