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土壤盐渍化和次生盐碱化是制约黄河三角洲农业可持续发展的关键障碍因子,了解和评估耕地土壤盐分的时空动态是对其进行科学利用和改良的前提。本文以黄河三角洲滨海盐碱地棉田为研究对象,在降水集中月份前后用EM38-MK2大地电导率仪测量了棉花两个关键生育期土壤根系层0~0.375 m和0~0.75 m剖面的土壤表观电导率,深入分析了棉花根区土壤表观电导率在空间上的分布特征与影响因素。结果表明:1)在降雨前后,黄河三角洲滨海土壤盐分空间变异较大,达到或超过中等变异水平;2)通过对大地电导率进行校正,排除影响其读数的干扰因素影响,大地电导率能快速表征0~0.375 m/0~0.75 m两个关键层次土壤盐分状态,可有效用于滨海棉田的土壤盐渍化的监测和评估;3)结合黄河三角洲地区地形地貌特征、降水蒸发、作物综合长势等因素的区域调查,作者认为在区域尺度上,优化土地利用格局,加强农田基本水利建设;在田间尺度上,加强土地平整和灌排配套等措施是治理和改良滨海盐碱土的基础。
Soil salinization and secondary salinization are the key barriers to agricultural sustainable development in the Yellow River Delta. Understanding and assessing the spatio-temporal dynamics of soil salinity in arable land is a prerequisite for their scientific utilization and improvement. In this paper, the coastal saline-alkali soil cotton field in the Yellow River Delta was selected as the study object. The soil electrical conductivity of 0 ~ 0.375 m and 0 ~ 0.75 m soil profiles in two key growth stages of cotton were measured by EM38-MK2 earth conductivity meter Rate, in-depth analysis of cotton root zone apparent electrical conductivity in the spatial distribution characteristics and influencing factors. The results showed as follows: 1) Before and after rainfall, the spatial variability of salinity in the coastal waters of the Yellow River Delta was large and reached or exceeded the level of medium variation; 2) By correcting the conductivity of the earth and excluding the interference factors that affect its readings, Characterization of soil salinity status at 0 ~ 0.375 m / 0 ~ 0.75 m can effectively be used for the monitoring and assessment of soil salinization in coastal cotton fields. 3) Combining with the topography and topography of the Yellow River Delta, rainfall evaporation, crop general growth And other factors, the author thinks that on the regional scale, optimizing the pattern of land use and strengthening the basic water conservancy construction in farmland; on the field scale, measures such as land leveling and irrigation and drainage coordination are the foundation for the treatment and improvement of coastal saline-alkali soil.