为了掌握黄河三角洲地区土壤有机质的空间变异,以黄河三角洲典型县域垦利县为研究区,通过土壤采集、分析,利用GIS软件研究其土壤有机质在空间上的变异特征。研究结果表明:研究区土壤有机质含量较低,平均值为11.37 g/kg;变异强度不大,变异系数为27.19%;土壤有机质在垦利县东部分布相对稍高,呈狭长条带状,该处靠近黄河口,有机质存在冲积、淤积;垦利县南边土壤有机质含量较低,该区域属于滩涂、沙地,有机质富集不明显;研究区地形地貌平坦,农田基础设施配套良好,排水能力强,灌溉条件好,水源充分,上述因素空间上较为一致,对土壤有机质的空间变异影响不大;土壤类型、成土母质、地形对土壤有机质也没有显著影响。土壤质地对土壤有机质含量空间变异的影响还需要进一步研究。

The variation of soil organic matter plays an important role in soil fertility evaluation. In this paper, the variability of soil organic matter in space is analyzed by using geographic information system software. Soil samples were collected from Kenli County, a typical district in the Yellow River Delta. Results show that the content of soil organic matter in the study area is low, with an average value of 11.37 g/kg. The coefficient of variation is 27.19%, indicating that the total variance of intensity is not big. Soil organic matter is relatively large in content in the east part of Kenli County and distributes in a narrow strip as the east Kenli is adjacent to the mouth of the Yellow River, resulting in the deposition of soil organic matter; whereas in the south part where land use types are beach and sand, the content of soil organic matter is relatively low, and the accumulation of soil organic matter is not obvious. The study area is located in the downstream of flat river delta with enough farmland infrastructure facilities, strong drainage capacity, good irrigation conditions, as well as abundant water sources, which have little effect on the spatial variance of soil organic matter. Soil type, soil parent material, and topography have no significant effect on soil organic matter in the study area either. The effects of other factors on the spatial variability of soil organic matter content need further research.