砾土质戈壁滴灌湿润模型研究

【目的】通过对砾土质戈壁进行滴灌试验,研究不同灌溉时间和滴头流量对土壤湿润体特征的影响,为滴灌系统的科学设计和水分精确管理制度提供理论依据。【方法】以砾土戈壁土质为研究对象,设计不同灌溉时间(4、6和8 h)与不同滴头流量(4.0、6.0和8.0 L/h)的双因素试验,观测土壤湿润体水平扩散距离和垂直入渗深度。【结果】砾土戈壁滴灌湿润体近似旋转抛物体,随着灌溉时间和滴头流量的增加,土壤湿润体水平扩散距离和垂直入渗深度均呈现增加的趋势;并得出湿润模型的非线性回归方程D=(17.353+0.788q)Q~(0.512)(R=0.954,P<0.001)和H=(56.887+1.541q)Q~(0.271)(R=0.966,P<0.001),根据经验公式计算出滴头流量为5.0 L/h为宜,灌水时间以6～8 h为宜,不宜超过8 h,滴头间距为100 cm左右。【结论】初步探索出砾土质戈壁滴灌湿润模型,为滴灌设计参数和滴灌灌溉制度的确定提供一定理论依据。

Moist Model of Gobi Drip Irrigation on Gravel Soil

Objective]The purpose of this research aimed to provide the theoretical basis for scientific design and water precise management of drip irrigation through drip irrigation tests of the gravel soil in the gobi to study the different effects of the irrigation time and drops of the emitters on moist soil body features. Method]The gravel gobi desert soil was taken as the research object,different irrigation times(4,6,8 h),double factors test of different drops of head flow(4.0,6.0,8.0 L/h) to observe,diffusion distance level of moist soil body and vertical diffusion depth.Result]The results showed that the gravel soil moist approximates body rotation object.With the increases of irrigation time and flow,the diffusion distance of moist soil body level and vertical diffusion depth are increasing;And they nonlinear regression formula:D = (17.353+0.788 q)Q~(0.512)(R =0.954,P<0.001)H=(56.887 + 1.541 q)Q~(0.271)(R =0.966,P<0.001)The above relations have the very high correlation.According to the empirical formula,the drop for head flow 5 L/ h and irrigation time to 6 - 8 h are advisable,no more than 8 h.The drop head spacing is around 100 cm. Conclusion]The researched tentatively explored the gravel soil moist model so as to provide drip irrigation system design parameters and provide theories for the determination of irrigation system.