基于单作物系数法指导南疆棉花膜下滴灌试验研究

Experimental Research on the Irrigation System of Mulched-cotton by Drip Irrigation in South Xinjiang Based on the Single Crop Coefficient

单作物系数法是将农田的蒸发和蒸腾结合起来考虑计算作物蒸发蒸腾量的方法,具有计算简单和对数据量要求低等优点。为探究基于单作物系数法指导南疆棉花膜下滴灌的最优灌溉制度,本试验于2019-2020年在南疆阿拉尔市进行田间试验。试验灌水时间设置3个水平,分别为当棉田每日作物蒸发蒸腾量与降水量差值累计达到25、30和35 mm时进行灌溉,其对应的灌水定额分别为30、36和42 mm,共计设计3个处理方案,每个处理重复3次,研究不同灌水处理对土壤水分变化、棉花生长、产量及水分利用效率的影响。通过两年的田间试验,综合灌水量、产量和水分利用效率等因素考虑,认为当棉田每日作物蒸发蒸腾量与降水量差值累计达到25 mm时进行灌溉,灌水定额30 mm和生育期内灌水11次的组合,可提高棉花的产量和水分利用效率,适用于新疆南疆地区棉花膜下滴灌的灌溉管理,可为未来实现灌溉自动化提供理论参考。

The single-crop coefficient method is calculating crop evaporation and transpiration based on evaporation and transpiration of the farmland.It is simple in calculation and requires fewer data.In order to explore the optimal irrigation system of cotton under mulch drip irrigation based on single-crop coefficient method in southern Xinjiang,this paper carries out the experiment in Alaer City in southern Xinjiang from 2019 to 2020.Three levels of irrigation time are set in the experiment.When the difference between daily crop evaporation and transpiration and precipitation reaches 25,30 and 35 mm,the corresponding irrigation quota is 30,36 and 42 mm,respectively.A total of 3 schemes are designed,and each scheme is repeated three times to study the effects of different irrigation treatments on soil water change,cotton growth yield and water use efficiency.When the difference between daily crop evaporation and transpiration and precipitation reaches 25 mm,the combination of 30 mm irrigation quota and 11 times of irrigation in growth period can ensure cotton yield and significantly improve water use efficiency,which is suitable for the irrigation management of cotton under mulch drip irrigation in southern Xinjiang,and provides a reference for achieving irrigation automation in the future.