我国东部水蚀区坡耕地土壤质量现状分析

发布时间：2019-01-02 08:35

【摘要】：土壤质量是土地生产力的基础,为探讨我国东部水蚀区坡耕地土壤质量现状,笔者采集36个样点表层0~20 cm土样,测定28项土壤理化指标,利用主成分分析法确定表征土壤质量的关键指标,根据指标隶属度与权重采用加权连乘法计算各采样点的土壤质量指数。结果表明:1)速效磷的变异系数最大,微团聚体体积分数的变异系数最小,绝大部分指标属于中等强度变异,土壤物理指标的变异系数明显小于土壤化学指标。2)黏粒体积分数、粉粒体积分数、微团聚体体积分数、有机质、p H值、Cd、Cr是表征土壤质量的关键指标,Cr隶属度最高,而p H值隶属度最低,Cd隶属度在二级水蚀分区间差异显著。3)36个采样点的土壤质量指数均值为0.64±0.16指数,6个二级水蚀分区间不存在显著差异。36个采样点土壤质量指数属较低、中等、较高和高等级的比例分别为8.33%、38.89%、36.11%、16.67%。总体而言,我国水蚀区坡耕地的土壤质量整体状况良好,但仍需要加强对土壤质量偏低地区的培肥改良。本研究对认识和维系我国东部水蚀区坡耕地土壤质量、分等定级与区划,合理开发利用坡耕地土地资源具有重要意义。
[Abstract]:Soil quality is the basis of land productivity. In order to study the present situation of soil quality in sloping farmland in the east of China, the authors collected soil samples from 36 surface soil samples for 0 ~ 20 cm, and measured 28 soil physical and chemical indexes. The key index of soil quality was determined by principal component analysis, and the soil quality index of each sampling point was calculated by weighted continuous multiplication according to the index membership degree and weight. The results showed that: 1) the coefficient of variation of available phosphorus was the largest, the coefficient of variation of volume fraction of microaggregate was the smallest, and most of the indexes belonged to medium intensity variation. The coefficient of variation of soil physical index was obviously lower than that of soil chemistry index. 2) clay volume fraction, silt volume fraction, microaggregate volume fraction, organic matter, p H value and Cd,Cr were the key indexes to characterize soil quality. The Cr membership degree was the highest, while the pH value was the lowest, and the Cd membership was significantly different in the second level water erosion score. 3) the mean value of soil quality index of 36 sampling points was 0.64 卤0.16. There was no significant difference among the six secondary water erosion subdivisions. The soil quality index of 36 sampling sites was low, medium, and the ratio of higher and higher grade was 8.333.89 and 36.11 and 16.67, respectively. In general, the soil quality of sloping farmland in water erosion area in China is good, but it is still necessary to improve the soil quality in the area with low soil quality. This study is of great significance in understanding and maintaining the soil quality, grading and regionalization of sloping farmland in the east of China, and in the rational development and utilization of sloping land resources.
【作者单位】：北京师范大学地表过程与资源生态国家重点实验室;北京师范大学地理科学学部;
【基金】：国家自然科学基金重点项目“退耕驱动近地表特性变化对侵蚀过程的影响及其动力机制”(41530858);国家自然科学基金创新研究群体项目“地表过程模型与模拟”(41621061)
【分类号】：S151.9

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