干旱状况下小区域灌溉冬小麦农田生态系统水热传输  

Effects of small area irrigation on water and heat transport of winter wheat field under drought condition

作　　者：郭家选[1] 李巧珍[2] 严昌荣[2] 梅旭荣[2] 李玉中[2] 

机构地区：[1]北京农学院植物科学技术系,北京102206 [2]中国农业科学院农业环境与可持续发展研究所水资源与旱地农业研究室,北京100081

出　　处：《农业工程学报》2008年第12期20-24,共5页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家科技支持项目(2006BAD04B06;2006BAD29B01;2006BAD29B02);科技部社会公益研究专项(2004DIB3J095);农业部专项"土壤有机质提升试点补助专项";北京市属市管高等学校人才强教计划资助项目

摘　　要：该文采用涡度相关技术测定小区域灌溉冬小麦农田实际蒸散量和农田能量平衡各分量,分析表征农田地表获取能量再分配经典参数Priestly-Taylor系数(α=LE/LEeq)的变化特征。结果表明,在华北地区冬小麦返青至成熟期内,日变化过程中白天时间段内,Priestley-Taylor系数呈"U"型变化趋势,7︰00～18︰00时刻内,α平均值为(1.324±0.334),正午前后保持在1.05～1.17之间。在冬小麦生育期季节变化过程中,Priestley-Taylor系数(α)平均值为(1.473±0.454),远高于在湿润下垫面时(α=1.26)的数值,在抽穗开花期内土壤水分充足时α最大值为2.317,拔节时期土壤水分胁迫时α值为0.410。干旱少雨状况下,进行小面积充分灌溉时,由于存在农田热平流现象将导致过多的蒸发蒸腾水分耗散,降低农田灌溉水的利用效率。Actual evapotranspiration and components of field energy balance were measured by eddy correlation system,and the variations of Priestley-Taylor parameter（α）,characterizing the energy partition over winter wheat field surface were analyzed.At the diurnal course,daily average of parameter α was 1.324±0.334,at noon,the value was 1.05-1.17.And the graph of parameter α with time had a concave-up shape from 7：00 to 18：00 after regreening stage in winter wheat field in the North China Plain.The seasonal average of parameter α was 1.473±0.454,above the value of 1.26 under wetness surface.The maximum of parameter α was 2.317 under the condition of enough soil water content during winter wheat tassel and anthesis stage,and the minimum of parameterαwas 0.410 with soil water stress during stem elongation in winter wheat field.Water use efficiency of small area irrigation in wheat winter field is decreased because of heat advection under drought condition.

关 键 词：农作物 小区域灌溉 生态系统 冬小麦农田 涡度相关法 Priestley-Taylor系数 水热传输 

分 类 号：S511.072[农业科学—作物学]