知识与财富的链接
了解污灌土壤微量元素含量空间分布特征是进行土壤环境评价的重要前提。应用地统计学技术对北京东郊污灌区典型地块8种微量元素含量和土壤理化参数进行了空间结构分析。结果显示,元素在迁移过程中趋向于在排污口附近就近富集,各微量元素含量分布的空间差异性较一般非灌溉农业土壤有所增大,且空间结构特征极为相似。同时,由于采样密度和范围的限制,更细微和更大尺度的空间结构特征尚不能得以表述。
The experimental results of geochemical speciation in the soils show that more than 85% of 7Be, 137Cs, 226Cs and 228Cs are bound to organic matter, Fe Mn oxy hydroxide and residual fractions. They can be moved with soil particles and used as tracers for erosion and/or accumulation of soil particles. 7Be geochemical speciation in the soils agrees with its trace for seasonal particle transport. 137Cs geochemical speciation is suitable to trace soil particle accumulation as well as sediment dating. 226Cs and 228Cs are combined in crystalline skeleton of clay minerals and mainly remain as a residue in the soils and very little is bound to the soluble, exchangeable, carbonate fractions. The differentials of 226Cs/ 228Cs activity ratios in different geochemical speciation in the soils can be used as a parameter to trace accumulation and/or erosion of soil particles.
