中文摘要：

以宁夏银北灌区5个沟水利用点为例,分析评价排水沟水的化学特征、沟水灌溉的盐渍化风险及灌溉后的土壤环境效应。分析表明,暖泉农场排水沟水为重碳酸盐钠型水,其它均为氯化物钠型水。灌溉中后期排水沟水各项盐渍化指标明显小于灌溉初期,除前进农场外,沟水灌溉的盐渍化危害程度较轻。土壤中盐类主要成分为钠、钙的氯化物一硫酸盐;土壤质地对灌后的盐渍化有明显影响,质地较轻的沙壤土不易积盐;长期淹灌种植水稻,地下水位较高,为保持土壤性状良好,宜改为水旱轮作方式。采用与耐盐作物轮作、引山洪水冲洗及实行水旱轮作等,能起到良好的调节水盐改良土壤作用,沟水灌溉的效果比较稳定。

英文摘要：

This paper analyzed the chemical characteristics of drainage water in ditches,saline-alkaline hazard and its impact of drainage reuse on soil in Yinbei irrigation districts,Ningxia.The result showed that the hydro-chemical type of drainage water is CNa at the Nuanquan Farm and ClNa at other four plots.Every alkaline index in drainage water was obviously smaller during the middle-late irrigation than those during the early irrigation.Except for the Qianjin Farm,the saline-alkaline hazard of drainage reuse for irrigation was relatively slight.The dominant soluble salt in soil was Chloride-sulfate bearing sodium and calcium.The soil texture had an obvious impact on soil saline-alkaline after irrigation.The lightly textured soil,such as sandy loam,was not easy to accumulate the salt.In the area where the rice was planted for a long term,the groundwater level was higher and the better choice was to adopt the paddy-upland rotation system in order to maintain the effect of soil improvement.Adopting rotation system with anti-saline crops,soil flushing with fresh water,paddy-upland rotation and so on would play an important role in controlling soil water-salt and improving the soil and the effects of drainage reuse for irrigation were good.