不同灌水水平下一膜两年覆盖的玉米农田土壤水分和经济效益分析

Soil moisture and economic benefits of maize field by 2 years plastic film mulching 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水分和产量的影响,以期为灌区玉米生产优化耕作措施、地膜再利用、提高水分利用效率提供理论依据。结果表明,一膜两年覆盖可显著提高播前农田0~60 cm土层土壤含水量和土壤贮水量(0~120 cm),一膜两年覆盖农田贮水量较传统耕作覆膜提高13.31%,且处理间差异显著;在玉米生育期一膜两年用地膜覆盖可明显提高0~30 cm土层土壤含水量,一膜两年用较传统覆膜处理0~30 cm土层土壤含水量提高7.67%,而不同处理对30~120 cm土层土壤含水量影响较小。高灌水水平下,一膜两年覆盖方式可达到与传统耕作覆膜方式相当的产量,在中、低灌水水平下高于传统覆膜处理,分别增产2.40%和16.39%,且在低灌水水平下WUE在不同覆膜方式处理间存在显著差异,一膜两年覆盖的WUE分别较秋免耕春覆膜和传统耕作覆膜高出5.25%和20.26%;此外,一膜两年覆盖方式可显著减少成本投入,产投比分别较秋免耕春覆膜和传统耕作覆膜提高7.27%和15.69%。说明一膜两年用地膜覆盖可显著提高播前和生育期0~30 cm的土壤含水量,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,提高作物子粒产量和水分利用效率,降低成本投入,提高产投比,是适于西北绿洲灌区的覆膜农田管理新技术。

In order to provide the theory basis for optimal tillage measures, film mulching reuse and increasing water use efficiency of maize in oasis irrigation district, under different irrigation levels and minimal/no tillage with plastic film mulch, taking the maize field as the research object, the effect on soil water content and yield of maize by 2 years film mulching, no tillage in autumn and mulching in spring and traditional tillage plus mulching have been researched. The results showed that： before sowing the soil water content in 0 to 60 cm and soil water storage in 0 to 120 cm can be sig-nificantly increased by 2 years plastic film mulching treatment, compared with the traditional tillage plus mulch, the soil water storage can be increased 13.31% , also the difference between treatment was significant. In addition, the soil wa-ter content in 0 to 30 cm can be increased 7.67% during maize growing period, but the effect of different treatment to soil water content in 30 to 120 cm was less. Under high irrigation level, the crop yield by 2 years plastic film mulching can be reached same as the traditional tillage plus mulch, but it was high under middle and low irrigation level, the yields were increased 2.40% and 16.39% respectively. Also, the water use efficiency （WUE） was exsisted significant difference between each mulching treatment under low irrigation level, the WUE by 2 years film mulching was higher than 5.25% and 20.26% compared with no tillage in autumn and mulching in spring and traditional tillage plus mulching. In addition, the production cost by the mode of 2 years plastic film mulching can be significantly decreased, the input- out-put ratio was higher than 7.27% and 15.69% with no tillage in autumn and mulching in spring and traditional tillage plus mulching. This can be explained that： the soil water content in 0 to 30cm before seeding and during growth period can be significantly increased by the mode of 2 years plastic film mulching, under low irrigation level as water stress, the drought water stress can be moderated, increased crop grain yield, WUE and the ratio of input and output, decreased the production cost by the mode of 2 years plastic film mulching. So it was a new management technique for the oasis irriga-tion district in northwest region of China.