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基于土壤质量调查的空间结构及分布规律研究对土地利用规划以及农业区划的制定等工作有重要意义。以成都平原为研究区,利用GIS的空间分析功能结合地统计学方法,以半方差函数、克里格插值为工具对成都平原土壤质量要素在不同尺度与不同方向的空间结构变化进行定量分析,揭示了在区域尺度下土壤质量的空间变异规律。结果表明,各土壤质量要素在结构变异方向、变程等参数上表现出明显差异,说明以成土过程为代表的结构因素以及以人为扰动为代表的随机因素对各质量要素产生了差异化影响,通过计算发现所有土壤要素在不同方向上均存在基台值或变程的差异,且多数指标不同方向空间自相关的距离要比各向同性距离大,表明土壤特性经角度分解后空间自相关性增强。pH值以及对数转换后的物理黏粒含量、速效磷、微团聚度、CEC等指标变异函数曲线符合球状模型,而有机质、容重以及对数转换后的全氮、碱解氮、速效钾、全钾等指标变异函数曲线符合指数模型。有机质、CEC空间分布的均一性较强,在小范围内的变异不显著,整体分布趋向均一;土壤物理性质与pH值分布的均一性较差,在小范围内的变异很强。pH值、有机质、物理黏粒、全钾、速效磷、速效钾在不同尺度上受不同的重要过程控制。在引起空间变异的影响因素方面,有机质、速效钾、全钾的空间变异主要是由随机性因素引起的,而物理黏粒含量、碱解氮、速效磷、全氮、pH值、容重、微团聚度的空间变异主要由结构性因素引起。
Research on spatial structure and distribution based on soil quality survey is of great significance to land use planning and formulation of agricultural zoning. Taking Chengdu Plain as a research area, the spatial analysis function of GIS and geostatistics methods were used to quantitatively analyze the spatial structure changes of soil quality elements in different scales and different directions in Chengdu Plain by means of semi-variance function and Kriging interpolation. The spatial variation of soil quality at the regional scale was revealed. The results showed that all the soil quality elements showed obvious differences in the direction of structural variation and parameters such as the range of variation, indicating that the structural factors represented by soil-forming processes and the random factors represented by man-made disturbances had a differentiated impact on the quality elements The results showed that there were differences in the abutment value or variation in all directions of soil elements in all directions, and the autocorrelation distances of most indexes in different directions were larger than the isotropic distances, indicating that the spatial autocorrelation Sexual enhancement. The curves of pH, logarithm-converted physical clay content, available phosphorus, microaggregation, CEC and other indicators fit the spherical model, and the organic matter, bulk density and log transformed nitrogen, All potassium and other indicators of variation curve in line with the index model. The homogeneity of the spatial distribution of organic matter and CEC is strong, the variation within the small range is insignificant, and the whole distribution tends to be uniform. The homogeneity of soil physical properties and pH distribution is poor, and the variation within the small range is strong. pH, organic matter, physical clay, total potassium, available phosphorus, available potassium in different scales by different important process control. The spatial variation of organic matter, available potassium and total potassium were mainly caused by random factors in the influencing factors of spatial variation. However, the content of physical clay, available nitrogen, available phosphorus, total nitrogen, pH value, bulk density, micro Spatial variability of reunion is mainly caused by structural factors.