关键词: 玉米, 免耕, 地膜覆盖, 耗水特性, 产量

Abstract:

【Objective】Water resource scarcity is one of the most prominent constraints for agricultural production in arid irrigation areas, so maize production are mainly mulched with traditional plastic film. However, this process is increasingly challenged by extreme high-temperature and ecological environment pollution. This study investigated the feasibility of maintaining high water use via no tillage with plastic film reusing pattern, and the aim was to prove the theoretical support for the construction of efficient maize production technology with plastic film reduction.【Method】In 2017 and 2018, a field experiment was carried out in Hexi oasis irrigation region from Gansu province to determine the effects of different plastic film mulching and using patterns on soil water utilization of maize field. The treatments included no tillage with plastic film reusing pattern (no tillage with plastic film mulching, NM), no tillage in fall and new plastic film mulching in spring (reduced tillage with plastic film mulching, RM), and conventional tillage with annual new plastic film mulching (conventional tillage with plastic film mulching, the control, CM). 【Result】Compared with CM, the mean soil weight moisture content across the 0-120 cm soil depth was increased by 7.5% and 5.1% with NM and RM before the maize sowing, respectively, which created a good soil moisture environment for sowing of maize. NM had greater mean soil weight moisture content across the 0-120 cm soil depth by 5.0% and 4.7% than thant that under CM from sowing to jointing and silking to early-filling stages, respectively, which made up for the abundant demand of soil moisture for the vigorous growth of maize filling stage. Evapotranspiration under NM was increased until maize big-flare stage, decreased from maize silking to early-filling stage, and increased after maize early-filling stage, which was effectively coordinated with water demand contradiction of maize at each growth stages. Compared with RM and CM, NM increased soil evaporation before silking stage by 11.7% and 26.0%, and increased the ratio of soil evaporation to evapotranspiration (E/ET) by 13.4% and 19.9%, respectively. However, NM reduced soil evaporation after silking stage by 9.2% and 19.4%, and reduced E/ET by 9.7% and 20.7%, respectively. The results indicated that NM was beneficial to enhance the effective utilization of soil water after maize silking stage. Therefore, NM with no tillage and plastic film reduction obtained the same grain yield and water use efficiency for RM and CM.【Conclusion】The results showed that no tillage with plastic film reusing pattern did not lead to a decrease in the grain yield and water use efficiency of maize, compared with conventional tillage with annual new plastic film mulching, but it stabilized grain yield and water use efficiency, thus, this practice was a feasible measure to reduce plastic film input and stabilize productivity of maize production in the arid irrigated area of northwestern China.

Key words: maize, no tillage, plastic film mulching, evapotranspiration characteristics, yield