黄淮海北片麦田微喷灌水量对土壤贮水耗水及水分利用效率的影响

为有效应对灌溉水资源短缺,明确麦田微喷灌水量的土壤贮水耗水特征,在山西临汾盆地采用大区对比方法,开展了微喷灌水量对土壤贮水耗水及水分利用效率影响的研究。结果表明:返青期、拔节期、灌浆期及成熟期0—100,0—200,100—200cm土层土壤贮水量基本呈现随微喷灌水量的增加而提高,微喷灌水量150mm与75mm、150mm与0mm、75mm与0mm处理间返青期至成熟期0—200cm土层贮水量均存在显著性差异;播前至成熟期阶段0—100,0—200,100—200cm土层的土壤耗水量呈现随灌水量的增加而减小,其中浅层(0—100cm)耗水量所占0—200cm耗水量比例各处理均大于深层(100—200cm)耗水量所占0—200cm耗水量比例,随灌水量的增加浅层(0—100cm)耗水所占比例提高,而深层(100—200cm)耗水所占比例则降低,不同微喷灌水量0—100,100—200cm土层在不同生育阶段的耗水量与该阶段的初始贮水量均分别呈正相关和负相关;在微喷灌水量0～150mm范围内,水分利用效率和产量均随微喷灌水量的增加而提高,当灌水量达525mm时,产量虽有增加但水分利用效率下降,而灌溉水利用效率则表现为随灌水量的上升而下降。研究结果可为水资源短缺对小麦生产系统的影响提供理论依据和技术支撑。

Effects of Micro Sprinkler Irrigation Amounts on Soil Water Storage and Consumption and Water Use Efficiency in the North of Huang-Huai-Hai Wheat Field

In order to effectively cope with the shortage of irrigation water resources and to clarify the soil water storage and consumption characteristics in wheat field under micro sprinkler irrigation, the effects of micro sprinkler irrigation amounts on soil water storage and consumption and water use efficiency (WUE) were studied in Linfen Basin, Shanxi Province, by means of large-scale contrast method. The results showed that the soil water storage in 0-100, 0-200 and 100-200 cm soil layers at greening stage, jointing stage, filling stage and maturity stage increased with the increase of micro sprinkler irrigation amounts. The soil water storage in 0-200 cm soil layers from greening stage to maturity stage had significant differences between 150 mm and 75 mm of micro sprinkler irrigation amounts, 150 mm and 0 mm, and even between 75 mm and 0 mm. With the increase of micro sprinkler irrigation amounts from pre-sowing to maturity stage, soil water consumption in 0-100, 0-200 cm and 100-200 cm soil layers decreased. All the proportions of soil water consumption in shallow layer (0-100 cm) to the entire 0-200 cm were greater than those in deep layer (100-200 cm). And the proportions of shallow layer (0-100 cm) increased with the increase of micro sprinkler irrigation amounts, while those in deep layer (100-200 cm) decreased. The soil water consumption in 0-100 and 100-200 cm soil layers at different growth stages had positive and negative correlations respectively with the initial soil water storage in the corresponding stage. The WUE and yield increased with the increase of micro sprinkler irrigation amounts in 0~150 mm. When micro sprinkler irrigation amount reached 525 mm, the yield increased but WUE decreased. The irrigation water use efficiency (IWUE) decreased with increase of irrigation amounts. These findings an provide theoretical basis and technical support for the impacts of water shortage on wheat production system.