微尺度下植烟土壤养分的空间变异及分布特征

摘要

为促进烟田土壤养分的精细管理和合理施肥,以武隆烟区为例,采用GIS和地统计学相结合的方法,对其植烟土壤的养分空间变异进行分析.结果表明:除速效磷外,其他土壤肥力要素在整个研究区内均表现出中等变异水平.土壤有机质和速效氮、磷、钾的空间变异函数分别为球状、指数、指数、球状模型,其中,土壤碱解氮和速效钾具有较强空间相关性,而土壤有机质和速效磷具有中等的空间相关性.用普通克里格法对研究区土壤速效养分进行克里格插值的结果表明,速效磷在研究区内普遍缺乏,土壤有机质、碱解氮和速效钾含量中等偏高,且在研究区内表现出明显差异性.%In order to promote accurate management and proper fertilization of tobacco soil, spatial analysis on tobacco soil nutrients was conducted by GIS and geostatistics in the tobacco region of Wulong. The results showed that soil fertility factors were all at moderate levels in the whole research region except available phosphorus. The semivariograms for soil organic matter, and available nitrogen, phosphorus and potassium contents were all well fitted by spherical, exponential, exponential and spherical models. Soil available nitrogen and potassium showed strong spatial correlation, while soil organic matter and available phosphorus showed moderate spatial correlation. Ordinary Kriging method was applied to interpolate soil available elements in the research region. The results showed that available phosphorus was widely deficient in the research region, and the contents of soil organic matter, available nitrogen and potassium were at moderate levels, indicating all apparent discrepancy in the research region.