微咸水灌溉对土壤水盐分布的影响

Effect of Brackish Water Irrigation on Soil Water and Salt Distribution

土壤中盐分的变化会对农作物的生长产生影响,拟通过田间试验的方法,以衡水地区为例,研究该地区微咸水灌溉对土壤水盐分布的影响。结果表明:利用该地区地下微咸水对灌区玉米进行灌溉时,受气象因素影响,表层土壤含水率随时间变化较小,随土壤埋深的增加逐渐增大;含水率变化频率随埋深的增加逐渐减小;土壤表层含盐量最高,呈现明显的表层富集现象;在降水及灌溉水的作用下,土壤含盐量下降明显,由初始值2.39 g/kg降至1.40 g/kg;考虑地下水作用,土壤在160 cm处出现盐分富集现象;当土壤水分通量增大时,土壤接受降水补给,洗盐效果明显。

The change of salinity in soil will affect the growth of crops.In this paper,the effect of brackish water irrigation on soil water and salt distribution in Hengshui area was studied by field experiment.The results show that when maize was irrigated with the underground brackish water in this area,the surface soil moisture content changed little with time and increased gradually with the increase of soil depth under the influence of meteorological factors.The change frequency of soil moisture content decreased with the increase of soil depth.The surface layer of soil had the highest salt content,and presented obvious surface enrichment.Under the effect of precipitation and irrigation water,the soil salinity decreased significantly from the initial value of 2.39 g/kg to 1.40 g/kg.With the effect of groundwater,salt enrichment occurred at 160 cm.When the soil water flux increased,the soil was replenished by precipitation,and the effect of salt washing was obvious.