基于地统计和移动窗口法的坝上地区小尺度土壤盐分空间变异及其影响因素

采用原位测定法测定坝上地区典型河漫滩草地土壤盐分,分析不同深度土壤盐分含量的空间变异规律,并分别通过地统计和移动窗口法定量分析河流和微地形对小尺度土壤盐分空间变异的影响.结果表明:离水体越近,盐分值越大;土层越浅,盐分值越大;表层土壤盐分的变化大于底层;受人为扰动影响,土壤盐分与微地形呈低相关性;在地下水埋深较浅的地区,垄沟对盐分分布的影响相对较小.以移动窗口为基本单元可以使空间格局信息明晰化,为土壤盐分空间变异研究提供新途径.土壤盐渍化治理时要充分考虑水体、地形等因素的影响,对河流沿岸以及地下水埋深较浅的小高地等盐渍化易发区采用生物措施、工程措施及农化措施等方法进行重点防治.本研究结果可为小尺度土壤盐分空间变异影响因素的定量研究提供一定的参考,对坝上草原地区牧场土壤盐渍化问题的防治提供理论依据. 

Geostatistical analysis and moving window method study of spatial variability in soil salinity and influential factors at small scale in the Bashang region

Spatial variability of soil salinity in floodplain grassland in Bashang region was investigated in in situ measurements.River and microtopography effects on soil salinity at small scale were analyzed by geostatistical analysis and moving window method.Soil salinity was found to increase with distance to the river and soil depth.Changes in oil salinity gradients on the surface were found to be greater than at the bottom.For microtopography versus soil salinity the correlation coefficients were randomly distributed at the sampling point due to uncertainty of human interference For those areas with low underground water levels,ditches were found to have less influence on salinity distribution.Moving window method was successfully applied to obtain clear spatial information,and the method provided an alternative choice to study the spatial variability of soil salinity.Considering the water and microtopography,river bank and highland are susceptiblethe prone areas of soil salinity that need focal prevention and cure by biological physical and agro-chemical measures future research based on these results may lead to the prevention of soil stalinization in pastures.