调亏灌溉条件下紫花苜蓿生长、作物系数和水分利用效率试验研究  

Growth,Crop Coefficient and Water Use Efficiency on Field-grown Alfalfa under Condition of Regulated Deficit Irrigation

作　　者：杨磊[1] 杜太生[2] 李志军[1] 王振昌[1] 

机构地区：[1]西北农林科技大学旱区农业水土工程教育部重点实验室,陕西杨凌712100 [2]中国农业大学中国农业水问题研究中心,北京100083

出　　处：《灌溉排水学报》2008年第6期102-105,共4页Journal of Irrigation and Drainage

基　　金：国家自然科学基金重点项目(50339030);国家高技术研究(863)计划课题(2006AA100203)

摘　　要：为了探讨西北旱区饲草作物节水灌溉新途径，在石羊河流域下游民勤干旱荒漠绿洲区大田进行了不同调亏灌溉模式下紫花苜蓿生长、作物系数及水分利用效率试验研究。结果表明，第一茬不同调亏处理最终株高差异不显著，而返青期、分枝期土壤水分下限为55％田间持水量（θf）的水分亏缺有利于增加分枝数，而茎粗随灌水量增加而增加。不同处理的耗水强度总体趋势是随着供水量的增加而递增。作物系数（Kc）第一茬随生育阶段逐渐增大，全年Kc随茬次递减。第一茬土壤水分下限55％θf，的控水处理，有利于后继茬次生长，保证全年总产量最高。在石羊河流域水资源严重不足的情况下，调亏灌溉是一种有效的灌溉方式，在民勤干旱缺水地区苜蓿第一茬土壤水分下限不应低于55％θf，第二、三茬土壤水分下限保持（55％～70％）θf可以获得较高的产量和水分利用效率。A field experiment was carried out to study the effects of regulated deficit irrigation on alfalfa growth, crop coefficient and water use efficiency in desert oasis located in the downstream of Shiyang River Basin, Gansu province. The results showed that the differences between the final heights of the first crops were not significantly at the end of first crop growth stage, it could benefited the increasing of branches numbers when the lower irrigation limit was set to be 55%θf in the stage of growth stage and branching period. The diameters of stem increased with the increasing amount of water supplied. The overall trend in different treatments was that the rates of water consumption increased with the amount of water supplied. The value of K,. increased with flowing growth stages and decreased with flowing circles of growth, it could benefit the growth of following circle and increase the overall yield of alfalfa in the whole year when the lower irrigation was set to be 55%θf in the first circle of growth. It can be concluded that. regulated deficit irrigation in the oasis where water resource is scarce is an efficient irrigation method, and it could increase the yield of alfalfa as well as the water use efficiency in the condition of that the lower irrigation limit was set to be not less than 55%θf in the first circle of growth and （55%-70%）θf in the second and third circles.

关 键 词：调亏灌溉 紫花苜蓿 生长 作物系数 水分利用效率 

分 类 号：S541.9[农业科学—作物学]