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根据大气降水转化为地表水、土壤水和地下水平衡的原理,研究它们之间的转化关系及水盐运行规律.结果表明,华北平原水分运动以垂直向排补为主,入渗和灌溉回归补给占84%,人工开采和潜水蒸发排泄达99%;土壤水有效天然补给量占降水量的78%,潜水蒸发是土壤水主要给源,潜水埋深大于2.5m;土壤可溶盐呈积盐—脱盐交替状态,雨量大于25mm时为淋盐,大于300mm时为脱盐.丰水年入海排盐量大于山区下泄盐量,枯水年则处于积盐状态,调控地下水位埋深是防止土壤返盐的关键.
Based on the principle that atmospheric precipitation transforms into surface water, soil water and groundwater balance, the transformation relations between them and the law of water and salt movement are studied.The results show that the vertical movement of water in North China Plain is vertical, and infiltration and irrigation return supply Accounting for 84%, artificially mining and diving evaporative discharge of 99%; effective natural recharge of soil water accounted for 78% of precipitation, the main source of soil water evaporation, soil depth greater than 2.5m; - desalination alternating state, the rainfall is greater than 25mm when the salinity, more than 300mm when the desalination .Flooding year, the amount of salt discharged into the sea is greater than the amount of salt in the mountains, dry years are in salt accumulation, regulation of groundwater depth is to prevent soil The key to salt.