通过研究春小麦不同种植模式对秸秆留茬免耕的最低贮水量变化，为河西灌区春小麦秸秆还田高效生产提供依据。以河西灌区为研究区域，通过田间定位试验，探讨单作小麦、小麦‖大豆和小麦‖玉米3种典型春小麦生产模式下，秸秆留茬免耕对春小麦全生育期土壤最低贮水量的影响。结果表明，秸秆留茬免耕对春小麦土壤贮水量的调控作用明显，但受种植模式、土层深度及生育阶段的多重影响。单作小麦、春小麦‖大豆和春小麦‖玉米3种春小麦种植模式下，春小麦播期对土壤最低贮水量的提升主要集中在上部解冻层；苗期至孕穗期对多数土层的最低贮水量呈显著增长趋势，而灌浆期仅春小麦‖大豆模式下部分土层贮水量有所提升。收获后对土壤贮水量的提升作用主要表现在0~40 cm土层。秸秆留茬免耕显著提升春小麦播种至灌浆期0~100 cm剖面土壤最低累积贮水量，单作小麦、春小麦‖大豆、春小麦‖玉米增幅分别达2.52%～7.33%、3.25%～7.37%、2.81%～6.59%，全生育期0~100 cm土层平均最低贮水量显著增加4.20%、4.82%、4.23%。综上，秸秆留茬免耕通过优化土壤水分保持能力，为河西灌区春小麦生长提供稳定水分供给，对保障春小麦高产稳产具有重要意义。

This study investigated how different spring wheat cropping systems affected the minimum soil water storage under no-tillage with stubbles, providing a basis for efficient straw-returning production of spring wheat in the Hexi irrigation area. Using the Hexi irrigation area as the study area and conducting field-fixed experiments, effects of no-tillage with stubbles on the minimum soil water storage of spring wheat during the entire growth period were examined under 3 typical spring wheat planting modes: wheat monoculture, wheat-soybean intercropping and wheat-corn intercropping. Results showed that no-tillage with straw stubbles had a remarkable regulatory effect on the soil water storage of spring wheat, however, this effect was subject to multiple influencing factors of planting pattern, soil depth and growth stage. Under the 3 typical spring wheat planting modes of wheat monoculture, wheat-soybean intercropping and wheat-corn intercropping, the increase of minimum soil water storage during the sowing period of spring wheat was mainly concentrated in the upper thawed layer, the minimum water storage in most soil layers showed a significant increase from seedling to panicle stage, whereas only part of the soil layers of spring wheat-soybean intercropping had an increase in water storage during the filling stage. After harvest, the improvement of soil water storage was mainlyin the soil layer from 0 to 40 cm. No-tillage with straw stubbles significantly increased the minimum cumulative soil water storage in the 0 to 100 cm profile from sowing to filling period of spring wheat by 2.52% to 7.33%, 3.25% to 7.37%, and 2.81% to 6.59% for wheat monoculture, wheat-soybean intercropping and wheat-corn intercropping, respectively, and the average minimum soil water storage in the 0 to 100 cm soil layer during the entire growth period was significantly increased by 4.20%, 4.82%, and 4.23% for the 3 planting patterns, respectively. In summary, no-tillage with straw stubbles can provide stable water supply for spring wheat growth by optimizing soil water retention, which is of great significance to ensure high and stable yield of spring wheat.

S344；S512.1

国家自然科学基金(42167010)。