不同灌水水平下少耕地膜覆盖对玉米农田土壤温度和水分利用效率的影响

The effect of minimum tillage and mulching on soil temperature and WUE of maize under different irrigation levels

以大田玉米为研究对象,在少耕地膜覆盖和不同灌水水平下,研究了一膜两年用地膜覆盖、秋免耕春覆膜和传统耕作覆膜对玉米农田土壤温度和水分利用效率(WUE)的影响。结果表明:与传统耕作覆膜和秋免耕春覆膜两种新膜覆盖处理相比,一膜两年用处理在玉米播种到拔节期的增温效果显著低于新膜覆盖,农田0~25 cm土壤平均温度较传统覆膜处理低13.35%,而对玉米拔节期到成熟期的土壤温度无明显影响,且农田0~25 cm土层土壤积温差异也不显著,相同覆膜方式下不同灌水水平间有显著差异,随着灌水水平的降低土壤积温增加;一膜两年用地膜覆盖方式下玉米籽粒产量和WUE与两种新膜覆盖方式相当,中灌水水平下WUE最高,达到17.89kg·mm-1,且在低灌水水平下获得籽粒产量显著高于传统覆膜处理,一膜两年用覆盖、灌溉定额5 700 m3·hm-2较传统耕作覆膜、灌水定额5 700 m3hm-2处理的玉米产量高出16.39%。说明,一膜两年用地膜覆盖在玉米播种到拔节期的增温效应低于新膜覆盖,但并不影响籽粒产量的形成,且在存在水分胁迫的低灌水水平下一膜两年用覆盖模式可减缓干旱胁迫,提高作物籽粒产量,是适于西北绿洲灌区的具有较好经济效益和生态效益的覆膜农田管理新技术。

A field experiment of maize was conducted to evaluate the effect of different film mulching patterns（ one time plastic mulch used for 2 years,no tillage in fall and mulching in spring,traditional mulching） on soil temperature and WUE under different irrigation levels,with the aims of providing a better understanding of optimization of maize cropping system,film mulching re-utilization,and increasing of water use efficiency in oasis irrigation area. The results showed that the treatment of plastic mulching once and used for 2 years increased the soil temperature,but it was significantly lower than the treatment with new film mulching between seeding and jointing stage of maize. The mean temperature of 0 - 25 cm profile soil in treatment with one time plastic mulch used for 2 years was 13. 35% lower than the temperature in traditional mulching treatment. However,no significant effect was found on soil temperature during the maize jointing to maturation stage. And no significant difference on soil accumulated temperature of 0 - 25 cm profile under different film mulching patterns,but there was significant difference under the different irrigation levels. Compared with the other two mulching patterns,the grain yield and WUE were not significantly different from the treatment with one time plastic mulch used for 2 years,however,the WUE reached 17. 89 kg·mm^-1under the medium irrigation level,the grain yield was significantly higher than the traditional film mulching treatment. The production of maize in NTMI1 treatment was 16. 39% higher than CTMI1 treatment. We concluded that the treatment with one time plastic mulch used for 2years had a lower warming effect than the treatments with new film mulching,but did not affect the forming of seed of maize,it could also decrease the drought pressure and increase the yield potential and be considered as a new advanced technique of maize cropping system for both economic and ecological benefits in northwest oasis irrigation area of China.