周期性冬灌对新疆膜下滴灌棉田盐分和经济效益的影响

Effect of periodic winter irrigation on salinity and economic benefit of cotton field under mulched drip irrigation in Xinjiang

为探究周期性冬灌对长期膜下滴灌棉田盐分变化及棉花成活率和产量的影响规律,以长期膜下滴灌结合非生育期周期性冬灌模式的农田为例,监测棉田全生育期及非生育期盐分含量、棉苗成活率和棉花产量。研究结果表明:周期性冬灌对盐分淋洗效果明显,继续耕作盐分会有小幅度上升;该模式应用7a后,土壤盐含量基本稳定在一个较低水平内。2008年0~150cm观测层盐分质量分数为10~65g/kg,至2019年4次冬灌后下降到了3g/kg以下。周期性冬灌后0~20cm返盐最为明显,次年继续耕作至收获时返盐率均>40%。棉花成活率和产量成正比,且冬灌对其影响显著,2019年成活率和产量最高分别可达94.3%和7216.8kg/hm^(2)。采用该模式应用4年后,棉田成活率>60%,农田收支比大于1%。文中旨在探明周期性冬灌的条件下盐分长期变化规律,为农业可持续发展、盐碱地开发和改良提供理论依据和技术支持。

The arm of the study is to explore the influence of periodic winter irrigation on the long-term drip irrigation cotton field salinity changes,the cotton survival rate and yield.Taking the cotton field with long-term drip irrigation under mulch combined with periodic winter irrigation mode as research object,the salt content,seedling survival rate and cotton yield in whole growth period and non-growth period were monitored.The results of the study show that:periodic winter irrigation has a significant effect on salt leaching,and continued farming has a slight increase in salinity.After applying this irrigation mode for 7 years,the soil salt content is basically stable at a low level.In 2008,the salt mass fraction in 0-150 cm observation layer was 10-65 g/kg,and by 2019,it dropped below 3 g/kg after 4 winter irrigations.The salinity return at 0-20 cm was the most obvious after cyclic winter irrigation,and the salinity return rate for different observation layers was more than 40%when farming was continued in the following year.The survival rate of cotton was directly proportional to the yield,and winter irrigation had a significant effect on it.The highest survival rate and yield in 2019 reached 94.3%and 7216.8 kg/hm^(2),respectively.After 4 years of application of this mode,the survival rate of cotton field was more than 60%,and the ratio of farmland income to expenditure was more than 1%.This article aims to explore the long-term changes of salinity under the condition of periodic winter irrigation,and provide theoretical basis and technical support for the sustainable development of agriculture and the improvement of saline-alkali land.