半干旱地区不同前作模式对后茬大豆产量和土壤水分的影响

Effects of Different Pre-Production Patterns on Soybean Yield and Soil Moisture in Semiarid Region

土壤水分是限制旱作农业生产的重要因子。采用等值线法分析6种不同前作模式下后茬大豆田土壤水分的时空分布规律,并对其水分利用效率和产量进行比较,以期为筛选半干旱地区节水高效型种植模式提供理论依据。结果表明:不同前作模式下大豆种植季土壤水分的时空动态变化相似,土壤贮水量均先降低后增加;随着时间的推移和土层深度的变化,土壤水分动态变化有一定的差异。其中,谷子→甘蓝→马铃薯→大豆轮作模式等值线密集,耗水速率快;玉米→甘蓝→马铃薯→大豆轮作模式等值线最疏松,左部等值线边缘数值大,土壤贮水量变化较小。各种植模式之间大豆生育期的耗水量差异明显,且不同种植模式下大豆产量和水分利用效率差异显著。其中玉米→马铃薯→甘蓝→大豆轮作模式下大豆产量显著高于其他种植模式,达到3 767.39kg/hm^2,水分利用效率为12.83kg/(hm^2·mm)。因此,玉米→马铃薯→甘蓝→大豆的种植模式优于其他种植模式,是适宜半干旱地区的较好种植组合。

Soil moisture is an important factor limiting rainfed agricultural production. In this study, the temporal and spatial distribution of soil moisture in the soybean field after 6 different cropping pattems was analyzed by the method of contours, compared with water use efficiency and yield so as to provide a theoretical basis for screening water saving and high efficiency cultivation model in the semiarid region. The results obtained were as follows： it is similar that dynamics in spatial and temporal change of soil moisture in soybean planting season under different planting patterns, the soil water storage decreased first and then increased; soil moisture dynamic changes showed some differences with the passage of time and soil depth changes. Among them, millet--~ cabbage--＊ potato--＊ soybean pattem contour line intensive, water consumption rate was quick, corn→ cabbage→ potato→soybean planting pattern contour line was the most loose, the edge of the value of large, the soil pondage change was small. There were significant differences in water consumption of soybean growth period among different rotation cropping patterns, and there were significant differences in yield and water use efficiency by soybean under different cropping pattems. The yield of corn→potato→ cabbage→ soybean were significantly higher than that of other planting patterns, reached 3 767.39kg/hm2, water use efficiency of 12.83kg/（hm2·mm）. Therefore, as a well planting combination in this region, the treatment corn→ potato→cabbage→ soybean is better than other planting patterns.