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主要对膜下滴灌后的土壤盐分分布的特征进行了研究,结果表明:在生长期内,位于90 cm深土层内土体的平均含盐量在上升,出现了一定的积盐。在距地表40 cm深的范围内,则存在盐分定向迁移的现象,其积聚的范围主要分布在湿润区的边缘,其程度则取决于土壤质地、每次灌水量大小及气候等多种因素。经过一个灌溉周期后,土壤积盐区的含盐量可达到初始值的一倍左右。这一结论对干旱气候下膜下滴灌区的冬灌具有一定的实际指导作用,灌区应根据土壤含盐量的大小而决策是否需要冬灌,从而达到减少干旱区农业用水量过大的目标。
The characteristics of soil salinity distribution after drip irrigation under film were studied. The results showed that the average salinity of soils located in 90 cm soil layer was rising during the growth period, and a certain amount of salt accumulation appeared. At a depth of 40 cm from the surface, there is a phenomenon of directional salt migration. The extent of its accumulation is mainly on the edge of the wetting area. The extent of the salt accumulation depends on various factors such as the soil texture, the amount of each irrigation and the climate. After an irrigation cycle, the salinity of soil salt area can reach about twice the initial value. This conclusion has some practical guidance for winter irrigation in drip irrigation under arid climate. The irrigated area should decide whether it needs winter irrigation according to the salinity of soil, so as to reduce the agricultural water consumption in arid area.