咸水淋洗改良滨海盐渍土的潜力研究

Leaching Potential of Salt Water in Coastal Saline Soils

通过室内土柱模拟试验,研究了不同矿化度咸水对砂壤质滨海盐碱土土壤入渗特征的影响,以及咸水淋洗土壤水盐变化规律和节水潜力。研究结果表明,高矿化度咸水略微降低土壤入渗性能,但当淋洗水矿化度高于15.61g/L时,土壤入渗性能不再继续降低;不同矿化度水处理淋出液矿化度都经历快速下降、较快下降、缓慢下降3个阶段,土壤盐分随咸水淋洗水量的增加先上升,再经历急剧下降、快速下降、缓慢下降,土壤经咸水淋洗后盐分含量明显下降;根据水盐平衡预估咸水淋洗具有较高的节水潜力,5.35g/L和10.36g/L的咸水淋洗节水潜力分别约为48.08%,38.46%,海水淋洗节水潜力最小,约为24.04%。

By leaching small soil column simulation experiments with salt water,the infiltration characteristics and desalination principle of a sandy loam coastal saline soil,and water saving potential with salt water were studied.The results indicated that,the salt water had a light negative effect on soil infiltration characteristics,but infiltration ability no longer decreased when mineralization degree of salt water was above 15.61 g/L.The change of effluent＇s mineralization degree could be characterized by three stages during leaching process： sharp decline rate,fast decline rate and slow decline rate.The salt contents of soil increased firstly,but decreased sharply as effluent flowed out.The final salt contents of soil were clearly below the initial value.The water-saving potential of leaching saline soils with salt water was great,and the water-saving rate with salt water of 5.35 g/L,10.36 g/L and sea water was 48.08%,38.46% and 24.04%,respectively.