松嫩平原黑土区有机质空间分布特征及影响因素

为研究区域尺度土壤有机质分布特征及其影响因素,以松嫩平原黑土区中部为研究区,利用经典统计学、地统计学和多重分形结合方法,探究土壤有机质分布特征及其变异规律,通过方差分析法明确高程及土地利用类型对有机质含量影响程度。经典统计学分析表明,0～20和20～40 cm土层土壤有机质含量平均值分别为57.896和53.371 g·kg~(-1),处于较高水平,变异系数分别为0.462和0.498,均为中等变异;地统计学分析表明,0～20和20～40 cm土层土壤有机质块金系数分别为0.626和0.712,说明有机质均具有中等相关性,东北至西南方向和北向南方向土壤有机质均逐渐降低,高斯模型为不同土层土壤有机质最佳拟合模型;多重分形分析表明,0～20 cm土层有机质空间变异性略低于20～40 cm土层,低值决定其空间变异性;方差分析表明,高程越高土壤有机质含量越高,不同土地利用类型中有机质含量排序为:林地耕地草地。综合分析得出,有机质低值信息、高程以及土地利用类型对研究区土壤有机质影响较大。

Spatial distribution characteristics and influencing factors of organic matter in black soil region of the Songnen Plain

In order to study the distribution characteristics of soil organic matter and its influencing factors on the regional scale, the distribution characteristics and variation law of soil organic matter were explored by the combination of classical statistics, geostatistics and multifractal in the middle of the black soil region of the Songnen Plain. The degree of influence of elevation and land use types on organic matter content were determined by analysis of variance. The results of classical statistics showed that the average values of soil organic matter content in 0-20 and 20-40 cm soil layer were57.896 and 53.371 g· kg~(-1), which were at a high level. Two layers of soil organic matter content were moderately variable, and the coefficient of variation was 0.462 and 0.498, respectively. The results of geostatistics showed that the gold mass coefficients was 0-20 cm soil layer and 20-40 cm soil layer were 0.626 and 0.712, respectively, indicating that their organic matter had medium correlation. The soil organic matter content of the two layers of soil gradually decreased from northeast to southwest and north to south. The Gaussian model was the best fit model of soil organic matter in different soil layers.Multifractal analysis showed that the spatial variability of 0-20 cm soil layer was slightly lower than that of 20-40 cm soil layer, and the low value determined its spatial variability. Analysis of variance showed that the higher the elevation, the higher the soil organic matter content. The order of organic matter content in different land use types was forest land>cultivated land> grassland. Comprehensive analysis showed that low-value information of organic matter, elevation and land use types had a greater impact on soil organic matter in the study area.