不同滴灌灌溉制度对绿洲棉田土壤水热分布及产量的影响

【目的】探究不同滴灌灌溉制度对绿洲棉田土壤水热分布状况及对产量的影响。【方法】于2017年在策勒地区开展田间试验,设置了2种灌水模式:基于计算机模型的预报灌溉与基于土壤墒情的灌溉,每种灌水模式设置2种灌溉梯度:充分灌溉(100%)和非充分灌溉(75%的充分灌溉)。【结果】预报灌溉的土壤含水率和贮水量在花蕾与花铃期显著高于墒情灌溉;不同灌溉制度各剖面的土壤温度变化趋势一致,整个生育期的表层土壤平均温度表现为墒情亏缺最高,预报充分最低。作物产量在一定范围内随灌溉量的增加而增加,预报充分的产量较预报亏缺,墒情充分,墒情亏缺分别提高13.7%、12.1%、47.6%。水分利用效率表现为预报亏缺最高,且产量与预报充分的产量无显著差异。【结论】在策勒绿洲地区,预报亏缺灌溉可达到节水增产的目的。

Response of Water-thermal Distribution and Yield of Cotton to Different Drip Irrigation Schedules in Oasis Field

【Objective】Drip irrigation has been increasingly used as an efficient technique in water-scarce region and in this paper, we experimentally studied the effect of different drip irrigation schedules on water-heat distribution in soil and the associated yield of cotton in oasis field.【Method】The experiments were conducted in 2017 at a filed in Cele area. The irrigating time was determined based on a computer model prediction and soil moisture measurement respectively, each having two irrigation amounts: fully adequate irrigation(100%) and deficit irrigation with 75% of water used in the adequate irrigation.【Result】Soil water content and soil water storage during the flowering-buds and flowering stage in the irrigation determined by computer model were significantly higher than that in the irrigation determined by soil moisture measurement. Temperature distributions along the soil profile were consistent in all treatments, with the average temperature in the topsoil rising as the soil moisture decreased. The yield under adequate irrigation was higher than that under deficit irrigation. Adequate irrigation with irrigating time determined by the computer model increased the yield by 13.7%, 12.1% and 47.6%, respectively,compared computer-aided deficit irrigation, the adequate and the deficit irrigation determined by soil moisture measurement. In terms of water use, the computer-aided deficit irrigation was most efficient.【Conclusion】In Cele oasis area, the computer-aided deficit irrigation can save water and increase cotton yield, and hence is the most suitable irrigation schedule.