【摘要】 选择黑河上游天涝池流域为研究区,利用Lysimeter蒸散仪和蒸发皿,对亚高山草地蒸散发和水面蒸发进行实际观测。结果表明:在月尺度上,从4年的平均看,6月最大,其次是8月,7月最小;6、7和8月的日均蒸散发量都是在2013年最大,其次为2011年,然后是2014年,2012年最小;2011和2012年中,每月的日均蒸散发量大小顺序为6月>8月>7月;在2013年中,8月份日均蒸散发量最大,其次为6月份,7月份的日均蒸散发量最小;但在2014年中,7月份的日均蒸散发量最大,8月份和6月份的相对较小。草地日均蒸散发量成波动状态,与降雨有一定的关系,降雨在一天内出现的时间不同,对蒸散发的影响也不尽相同。日蒸散发量与环境因子之间的相关关系为:风速>饱和水汽压差>相对湿度>净辐射,R~2分别为0.4174、0.3598、0.3461和0.3322,四个气象因子对日蒸散发量都有较大的影响。通过对典型晴天下小时尺度实际蒸散发量与蒸发皿蒸散发量的关系的分析,将蒸发皿系数分为8:00—14:00和14:00—20:00两个时间段和8:00—20:00整个时间段来计算,8:00—14:00和14:00—20:00时间段的蒸发皿系数分别大于1和小于1,而8:00—20:00整个时间段蒸发皿系数小于1。更多还原

【Abstract】 Tianlaochi catchment in the upper reaches of Heihe River was selected as a study area,and lysimeter was used to observe the evapotranspiration of subalpine meadow.The result showed that at the month scale,the order of the average daily evapotranspiration was 2013>2011>2014>2012.In the year 2011 and 2012,the order of the average daily evapotranspiratio of every month was June>August>July,and in the year 2013 and 2014,the orders were August>June>July and July> August>June.The average daily evapotranspiration had a certain relationship with the rainfall;the time of rain in one day was different,having different effects on evapotranspiration.The relationship between daily evapotranspiration and meteorological elements was wind speed>saturated vapor pressure>relative humidity>net radiation;the R~2 was 0.4174,0.3598,0.3461 and 0.3322.All the four meteorological elements had an affect on daily evapotranspiration.The relationship between hourly actual evapotranspiration and pan evapotranspiration was analyzed based on a typical sunny day.The pan coefficient was divided into 8:00-14:00 and 14:00-20:00,and the whole time was 8:00-20:00;the pan coefficient of 8:00-14:00 was greater than 1 but that of 14:00-20:00 was less than 1.The pan coefficient of 8:00-20:00 was less than 1.更多还原