不同施肥处理下麦田水分利用过程及其效率特征

Characteristics of Water Utilization Process and Efficiency under Different Fertilization Treatments in a Wheat Field

通过田间试验(2010—2011年),就不同施肥处理下麦田水分利用过程及其效率特征进行研究。结果表明:施磷量为90kg/hm2条件下,配施氮量在0～135kg/hm2时,农田耗水率(农田耗水量占总的供水量的比率,ET/SW)和蒸腾比率(蒸腾量占农田耗水量的比率,T/ET)随配施氮量的增加逐渐提高,考虑蒸腾消耗的作物水分利用率(籽粒产量与蒸腾量的比值,Y/T)和降水利用效率(Y/P)在施氮量为180kg/hm2时达到最大。施氮量为90kg/hm2条件下,配施磷量在90～180kg/hm2时,各处理的农田水分消耗率、蒸腾比率几乎相同,但明显高于单施氮肥处理,只考虑蒸腾消耗的作物水分利用率随施磷量的增加逐渐提高,降水利用效率在施磷量为90kg/hm2时达到最大值。与不施肥处理相比,施磷量为90kg/hm2与施氮量为180kg/hm2处理的麦田,冬小麦从拔节期至成熟期的农田耗水量增加23.5%,蒸腾量增加186.8%;农田水分消耗率提高10.5%,作物蒸腾比率提高200%,作物水分利用效率(Y/ET)达到11.13kg/(hm2.mm),降水利用效率达到18.73kg/(hm2.mm)。

Characteristics of water utilization process and efficiency under different fertilization treatments were studied through a field experiment conducted from 2010 to 2011. Results showed that under the condition of 90 kg/hm2 P application, the ratio of cropland water consumption to total supplied water （ET/SW） and the ratio of total transpiration to cropland water consumption （T/ET） gradually increased with the in- creased rate of N application if the rate of N application was between 0 and 135 kg/hm2 , but crop water use efficiency with transpiration considered only （the ratio of grain yieldto total transpiration, Y/T） and precipi- tation use efficiency （PUE） reached the highest value when the rate of N application was 180 kg/hm2. Under the rate of 90 kg/hm2 N application, the ET/SW was almost the same as the T/ET if the rate of P application was between 90 and 180 kg/hm2, but significantly higher than single N application treatment. The Y/T was gradually increased with the increased P application under the same N application. However, PUE reached the highest value when P application was 90 kg/hm2. In contrast to no fertilizer application, the combined application of 90 kg/hm2 P and 180 kg/hm2 N in the winter field, from jointing stage to maturity of winter wheat, increased the amount of cropland water consumption by 23.5%, the amount of transpiration by 186.8%, the ET/SW by 10.5%, the T/ET by 200%, the water use efficiency （Y/ET） up to 11.13 kg/ （hm2·mm）, and PUE up to 18.73 kg/（hm2 ·mm）.