灌溉量对紫花苜蓿水分利用效率和耗水系数的影响

Effect of Irrigation Amount on Water Use Efficiency and Water Consumption Coefficient of Alfalfa

采用大型非称重式蒸渗仪法,在河北省坝上地区研究了灌溉量对紫花苜蓿(Medicago sativa L.)水分利用效率和耗水系数的影响。结果表明:随着灌溉量的增加,第1、2、3茬和全生长季(1～3茬)生物产量和经济产量水分利用效率皆呈现先升后降的趋势;第1茬中灌溉量处理显著高于低和高灌溉量处理(P<0.05)。随灌溉量增加,各茬次和全生长季(1～3茬)生物产量和经济产量耗水系数均呈先降后升趋势;第1茬中灌溉量处理显著低于低和高灌溉量处理(P<0.05)。不同茬次间水分利用效率及耗水系数差异显著(P<0.05)。

Effect of irrigation amount on water use efficiency（WUE） and water consumption coefficient（WCC） of alfalfa（Medicago sativa L.） was studied in Bashang area of Hebei province with lager scale no-weighting-lysimeter. The results showed that the WUE based on biology and economic yield of first harvest, second harvest, third harvest and whole growth season（lst- 3rd harvest） all gradually increased firstly, then decreased, as the irrigation amount raising. The WUE based on medium irrigation amount level of the first harvest was higher than that of low irrigation amount level and high irrigation amount level （P 〈 0.05）. The WCC based on biology and economic yield of first harvest, second harvest, third harvest and whole growth season（1st- 3rd harvest） all gradually decreased firstly, then increased, as the irrigation amount raising. The WCC based on medium irrigation amount level of the first harvest was lower than that of low irrigation amount level and high irrigation amount level （P 〈 0.05）. The difference of WUE and WCC between different harvest were significant （P 〈 0.05）.