摘要
蒸散发是地表能量循环与水循环的关键环节,蒸渗仪则是获取蒸散发量最为准确的仪器.但受到仪器噪声、风压等因素的影响,蒸渗仪数据在计算蒸散发量时会出现误差.本文通过对误差来源的分析,结合数据筛选阈值与数据平滑窗口大小的选择,给出蒸渗仪数据处理的一般流程,在此基础上分析了蒸渗仪观测蒸散发的季节变化,并与涡动相关所观察结果进行了对比.结果表明:本文的方法可以有效处理蒸渗仪数据,并解决了数据头尾作差计算而导致的蒸散量高估的问题,同时准确地计算蒸散发量;计算结果显示出怀来地区作物生长季内的蒸散规律——作物生长期间由于作物蒸腾作用,种植玉米蒸渗仪的蒸散发要高于裸土蒸渗仪的蒸散发,而生长末期由于蒸渗仪对桶内土壤水分的消耗,则呈现出相反的结果;同时,蒸渗仪观测结果与涡动相关仪观测结果也有良好的一致性,其之间的差异是由于灌溉不同步以及各自代表性不同所造成.
Evapotranspiration is a key link between surface energy cycle and water cycle. Lysimeter is the most accurate instrument to gauge evapotranspiration. True evapotranspiration cannot be calculated using lysimeter data, however, due to instrumental noise and the influence of wind. An analysis of error source helped to select data filtering threshold and size of data smoothing window, to outline the general process of data processing for lysimeter data. Seasonal variation in observed evaporation was then analyzed, and compared with the eddy covariance system. This method was found to be effective in dealing with lysimeter data and estimating evapotranspiration. The estimated data revealed a role of evapotranspiration in crop growing season in Huailai region. Due to crop transpiration, evapotranspiration of maize lysimeter was found to be higher than bare soil lysimeter. At the end of growth period, the result was found to be the opposite due to consumption of soil moisture by maize. The observed results of lysimeter were in good agreement with observed results of eddy covariance system. Any difference remained was due to non-synchronized irrigation and difference in representative ranges.
出处
《北京师范大学学报（自然科学版）》
CAS
CSCD
北大核心
2016年第5期628-634,共7页
Journal of Beijing Normal University(Natural Science)
基金
遥感科学国家重点实验室重大资助项目(270403GK)
国家高技术研究发展计划(863)资助项目(2012AA12A305)
关键词
蒸渗仪
数据处理
蒸散发
lysimeter
data processing
evapotranspiration
