干旱区生态环境知识资源中心(Arid): 冬小麦农田暂时水分胁迫状况下水、热通量日变化

Arid

	冬小麦农田暂时水分胁迫状况下水、热通量日变化
其他题名	Diurnal variation of water and heat flux under transient water stress in a winter wheat field
	郭家选 1; 梅旭荣 1; 林琪 2; 赵全胜 1; 卢志光 3
ISSN	1000-0933
出版年	2006
卷号	26 期号:1 页码:130-137
中文摘要	以冬小麦农田尺度为研究对象，采用涡度相关技术测定农田能茸平衡各分量，研究暂时水分胁迫状况下农田蒸散通量和蒸发比值（evaporative fraction）日变化特征。结果表明，冬小麦在农田郁闭（LAI≥3）且土壤含水量为田间持水量的55％-65％时，晴天日农田潜热通量日变化在正午前后存在明显的蒸散高地（evapotranspiration plateau）现象，持续时间达2．54h，表现为蒸散通量增量日变化突然极显著降低，即蒸散通量呈相对稳定、甚至下降的变化趋势；反映在蒸发比值日变化过程方面，夜间和日出日落前后时刻蒸发比值变化较大，7：00-18：00时段内蒸发比值曲线近似呈倒s型，9：00～16：00时段内蒸发比值比较稳定，正午前后蒸散高地出现时，蒸发比值有所下降大约在0．50．65范围内，12：0013：30时段内蒸发比值平均值接近9：0016：00时段内蒸发比值平均值。
英文摘要	An understanding how changes in evaporatranspiration and evaporative fraction （ EF）, the ratio of latent heat flux to the available energy （the value of net radiation flux subtract soil heat flux）, is important for determining the irrigation schedule in arid and semiarid area. In the present work, the evapotranspiration and EF over a closed-canopy of winter wheat with transient water stress was investigated over daily time courses at Luancheng Agro-ecosystem Station, Chinese Academy of Science in the North China Plain from 2001 to 2002. Surface energy fluxes including net radiation （ Rn ）, latent heat flux （ LE）, sensible heat flux （H） and soil heat flux （G） were measured based on the eddy covariance technique. When the soil water content was below 65% of field moisture capacity, a plateau in the evapotranspiration occurred during the middle part of clear days. The plateau was marked by a sudden change in slope of the evapotranspiraton curve, and lasted for about 2.5 - 4hr. Evapotranspiration flux indicated a change in the trend from a decline to relative stabilization. The EF showed a distinct diurnal variation. The stabilization of EF over daily time courses differed during each time period. It had a large variations during nighttime, aroundsunrise and at sundown, but little variation during the daytime from 9：00 to 16：00, and shape of the curve of EF was an inverse ＂S＂ shape from 7：00 to 18： 00. The value of EF declined and ranged from 0.5 to 0.65 when the evapotranspiration plateau occurred when the relative moisture of the soil ranged from 55 % to 65 %. Midday EF at 12：00 - 13：30 was nearly equal to the average daylight EF at 9：00 - 16：00 over a relatively homogeneous winter wheat field under clear sky conditions.
中文关键词	涡度相关技术 ; 水分胁迫 ; 潜热通量 ; 蒸发比值
英文关键词	eddy covarianee technique transient water stress latent heat flux evaporative fraction
语种	中文
国家	中国
收录类别	CSCD
WOS类目	METEOROLOGY ATMOSPHERIC SCIENCES
WOS研究方向	Meteorology & Atmospheric Sciences
CSCD记录号	CSCD:2243469
来源机构	中国农业大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/220018
作者单位	1.中国农业科学院农业环境与可持续发展研究所水资源与早地农业研究室, 北京 100081, 中国; 2.莱阳农学院农学系, 莱阳, 山东 265200, 中国; 3.中国农业大学资源与环境学院, 北京 100094, 中国
推荐引用方式 GB/T 7714	郭家选,梅旭荣,林琪,等. 冬小麦农田暂时水分胁迫状况下水、热通量日变化[J]. 中国农业大学,2006,26(1):130-137.
APA	郭家选,梅旭荣,林琪,赵全胜,&卢志光.(2006).冬小麦农田暂时水分胁迫状况下水、热通量日变化.,26(1),130-137.
MLA	郭家选,et al."冬小麦农田暂时水分胁迫状况下水、热通量日变化".26.1(2006):130-137.