节水灌溉条件下冬小麦耗水规律及其生态基础研究

Study on the Regularity Water Consumption of Winter Wheat and Its Ecological Basis under Water-saving Irrigation Conditions

从土壤水分、作物生长发育及气象条件三个方面分析了冬小麦农田耗水变化特点。结果表明:在土壤水分状况较好条件下冬小麦农田耗水强度呈双峰曲线变化,不同灌溉处理的耗水高峰出现时期及其峰值不同,而与灌水时期一致,同时灌溉能够明显降低冬小麦利用土壤底墒水能力。在拔节以前冬小麦农田耗水与大气蒸发力呈显著直线相关;拔节后与其干物质积累以及土壤水分含量呈显著正相关,拔节期是冬小麦需水的生理生态临界期。

The characteristics of field water consumption of winter wheat were studied from soil water content, crop growth and meteorological factors. The results showed: the changes of water consumption intensity by winter wheat showed 'double peaks' curves at better soil water conditions. Though the time and value of the peaks in different irrigation treatments were different, they accorded with the irrigation time. Irrigation reduced the ability in using pre-seeding soil moisture. Before jointing stage, the field water consumption of winter wheat and the atmospheric evaporation were of significant positive and linear correlation. After jointing stage, there was a positive linear-correlation between water consumption and dry matter accumulation or soil water content. Jointing stage is the critical stage of water consumption of winter wheat.