Bundled straw covering (BSC), using corn whole straw for partial coverage planting, is a novel dryland cultivation technique. To examine the effects of BSC on the thermal-moisture status and winter wheat yield under typical arid and semiarid conditions in the Loess Plateau of Northwest China, soil temperature, soil water content and consumption, grain yield and water-use efficiency were compared for four treatments, including no-tillage with straw mulch (NTS), whole field plastic mulching with soil covering on the top of the plastic mulch and bunch-seeding (PFM), open field cultivation (CK) and BSC during three growing seasons from 2013 to 2016. The results showed that PFM significantly increased soil temperature of 5-20 cm depth before jointing stage, while the warming effect of BSC and NTS was mainly in the wintering period. The three kinds of coverage methods after jointing stage had significant cooling effects. Both BSC and PFM significantly improved soil water storage effect during the fallow period. BSC significantly elevated soil moisture in the depth of 0 to 200 cm in the whole growing season. The improvement of soil moisture by PFM and NTS mainly occurred before the heading stage, and soil moisture in PFM treatment gradually decreased after heading stage. BSC and PFM significantly increased water consumption in the whole growth period and increased that during the jointing stage to the flowering stage, and promoted the utilization of soil moisture below 120 cm. Compared with CK, BSC, NTS and PFM significantly increased the number of panicles per unit area and biomass at maturity. In those three treatments, grain yield was increased by 19%-52%, 14%-30% and 15%-60%, respectively, and the annual water use efficiency was increased by 19%-61%, 14%-31% and 15%-58%, respectively. BSC had the same potential for increasing yield and water use efficiency as PFM. Based on factors such as winter wheat yield, soil thermal-moisture utilization and annual water consumption, BSC is a high-yield and efficient cultivation method that is conducive to the sustainable development of dryland agriculture in Northwest China.
秸秆带状覆盖技术是一种利用玉米整秸秆进行局部覆盖种植的新型旱地覆盖栽培技术.为明确西北黄土高原典型旱作条件下秸秆带状覆盖对冬麦田土壤水热动态特征和产量的影响,在2013—2016年3个生长季,比较了秸秆带状覆盖(BSC)、免耕秸秆覆盖(NTS)、全膜覆土穴播(PFM)和露地种植(CK)下麦田土壤水温动态、小麦耗水特征、产量和水分利用效率的差异.结果表明: PFM显著增加了拔节前5～20 cm土壤温度,而BSC和NTS的增温效应主要在越冬期,但拔节后3种覆盖方式均具有显著的降温效应.BSC和PFM显著提高休闲期土壤蓄水效果,BSC显著改善全生育期0～200 cm土壤墒情,但PFM和NTS对生育期土壤墒情的改善主要集中在抽穗期以前,抽穗后PFM土壤墒情逐渐低于CK.BSC和PFM在保持周年耗水与CK无显著差异的基础上,显著提高生育期耗水量,增加拔节至开花期阶段耗水量,促进对120 cm以下土壤水分的利用.与CK相比,BSC、NTS和PFM显著增加单位面积穗数和成熟期生物量,籽粒产量分别显著增加19%～52%、14%～30%和15%～60%,周年水分利用效率分别显著提高19%～61%、14%～31%和15%～58%.BSC取得与PFM相近的产量和水分利用效率双增潜力.综合冬小麦产量、水温利用状况、周年耗水等因素,BSC是一种高产高效且利于西北旱作农业可持续发展的种植方式.
Keywords: bundled straw covering; northwest Loess Plateau; soil thermal-moisture; winter wheat; yield.