垄膜沟秸秆种植方式对夏玉米水热效应的影响

针对黄土高原半干旱区降水短缺且时空分配不均,严重地制约了半干旱区农业发展的现状,通过研究垄膜沟秸秆种植方式下夏玉米水热效应,揭示其保水调温和作物增产的机理。试验于2014—2015年在陕西杨凌设置了露地处理(CK)与垄膜沟秸秆处理(RMFS)田间试验。结果表明:垄膜沟覆秸秆种植方式可以提高表层土壤含水量;土壤温度主要表现出"高温低调,低温高调"的现象;缩短作物生育历时及调节作物耗水量以改善水分的供需平衡,显著地提高土壤水分利用效率和积温利用效率,2a土壤水分利用效率和积温利用效率分别提高了39.85%,43.34%。垄上覆膜沟内覆秸秆处理通过改善土壤水热交互状态,提升作物产量,是一种适宜有效的覆盖集雨措施。

Effects of Plastic Film Combined with Straw Mulching on Soil Hydrothermal Regime of Summer Maize

In view of the fact that shortage and uneven temporal and spatial distribution of rainfall in the semiarid area of the Loess Plateau,this paper aimed to study the hydrothermal regime of the ridge-furrow planting mode,and reveal the mechanism of hydrothermal regulation and the enhancement of crop yield.Field experiments of open field treatment (CK) and plastic film combined with straw mulching treatment (RMFS)were conducted in 2014 and 2015 in Yangling,Shaanxi.The results showed that the plastic film combined with straw mulching cultivation had effects on the growth of summer maize,and the mulching could improve soil moisture condition.Soil temperature showed a phenomenon of ‘lowering the temperature when the temperature was high,and vice versa’.The RMFS treatment shortened the duration of crop growth and adjusted soil water consumption to improve the balance between water supply and demand.Soil water use efficiency and thermal time use efficiency was increased by 39.85％ and 43.34％ in the RMFS treatment within two years,respectively.Although water consumption could not be saved and soil thermal time was not increased,soil water use efficiency and thermal time use efficiency were significantly improved.In short,ridge covered plastic mulching with furrow covered with straw mulching treatment improved crop yield by improving the hydrothermal interaction regime.Plastic film combined with straw mulching treatment is a suitable effective practice to collect rainwater harvesting.