河套灌区节水灌溉对土壤盐分累积规律的模拟研究

在内蒙古河套实施农业节水对引黄灌区水资源可持续利用具有非常重要的意义。通过河套灌区土壤水盐动态的原位监测,并应用水盐运移和作物耦合模型HYDRUS-EPIC对不同灌溉条件下葵花土壤盐分累积规律进行分析。研究结果表明:现状滴灌条件下葵花生育期土壤表层(0~10cm)盐分呈累积趋势,全盐含量分别比传统地面灌溉和等量地面灌高115%和37%;葵花生育期0~100cm增加的全盐量(ΔC)滴灌比传统地面灌溉高305%,比等量地面灌溉低23%,淋洗是灌区滴灌不可或缺的抑盐措施;滴灌条件下葵花的产量比传统地面灌小6.5%;滴灌产量比等量地面灌高11.7%,增产效果明显。

Simulation the Response of Soil Salinity Accumulation to Irrigation Management Practice in Hetao Irrigation District

The implication of agricultural water management practice in Hetao Irrigation district is very important to the middle and lower reach of Yellow River.In this paper,soil water content,salinity and parameters of soil dynamics were analyzed based on the sampling tests at a special area in Hetao.The coupled model of salt transport and crop growth model HYDRUS-EPIC were adopted to analyze soil salinity accumulation of sunflower at different irrigation management practices.The results showed that the salinity of the top soil,e.g.0~10 cm,has the tendency of severe accumulation when drip irrigation is applied.It is around 115% and 37%higher than that of the traditional surface irrigation and surface irrigation with the same amount of water as drip irrigation after the crop grow season.The total amount salt increased at the depth of 0~100 cm in soil for drip irrigation is 305% higher than that of the traditional surface irrigation,while 23% lower than surface irrigation with the same amount of water at the end of crop growth.The yields of sunflower under drip irrigation is 6.5% less than that of the traditional surface irrigation,while 11.7% more than that of the surface irrigation with the same amount of water as drip irrigation.