涡度相关系统不同平均周期对干旱区玉米水热通量的影响  

Effects of Different Average Periods in Eddy Covariance on Calculation of Heat and Water Fluxes in Maize Field in Arid Region

作　　者：李佳[1] 陈岩 秦淑静 李思恩[1] LI Jia;CHEN Yan;QIN Shujing;LI Sien(China Agricultural University,Beijing 100083,China)

机构地区：[1]中国农业大学,北京100083

出　　处：《灌溉排水学报》2018年第9期69-72,共4页Journal of Irrigation and Drainage

基　　金：水利部公益性行业科研专项经费项目(201501016);国家自然科学基金优秀青年科学基金项目(51622907)

摘　　要：【目的】研究不同平均周期对涡度相关通量数据计算的影响,提高涡度相关数据质量和能量闭合率。【方法】采用Loggernet软件将2015年7月河西走廊地区制种玉米10 Hz涡度相关原始数据以1、2、5、10、15、30、60、120、180、360、720 min的不同平均周期进行分割,利用分割得到的数据计算了相应时段内的能量通量,并分析了不同平均周期对于不同灌溉方式下制种玉米能量通量计算的影响。同时,以30 min周期计算结果为标准,分析了不同平均周期对通量计算的影响。【结果】当平均周期小于30 min时,平均周期的改变只影响白天(07:00—20:00)的通量,平均周期越小,能量通量越小;当平均周期在30~180 min时,平均周期的改变对通量计算结果的影响因通量变化阶段的不同而不同,在通量上升阶段,平均周期的延长使通量减小,在通量下降阶段,平均周期延长使通量增加;当平均周期为360 min和720 min时,能量通量的计算结果误差明显,能量闭合率均不足40%。试验中15、60 min平均周期计算所得的通量闭合率最高,且15、60 min周期计算所得通量日平均值与30 min计算结果的相对误差最小,均小于1%。【结论】干旱区玉米水热通量计算的最适平均周期为15~60 min。【Objective】The accuracy of the eddy covariance is affected by various factors and the objective of this paper is to study of the impact of average period on water and heat fluxes in a maize field in arid region.【Method】The Loggernet software was used to analyze the 10 Hz eddy covariance data measured from a seedling corn field at Hexi Corridor of Gansu Province in July 2015 with the average period set at 1, 2, 5, 10, 15, 30, 60,120, 180, 360 and 720 min. The data obtained from the segmentation were used to calculate the energy flux in the corresponding period, and we then analyzed the effects of different average periods on the calculated energy flux from the field under different irrigation methods.【Result】When the average period was less than 30 min, the change in average period only affected the value of daily flux data. The smaller the average period was, the smaller the energy flux was. When the average period was within 30~180 min, the change in the average cycle had a great impact on the calculated fluxes. During the rising period of the fluxes, the energy flux decreased as the average period increased. With flux declining, increasing the average period led to an increase in the fluxes. When the average period was 360 min and 720 min, there was noticeable error in the calculated energy flux.【Conclusion】Average period in 15~60 min appeared to be most appropriate for calculating water and heat fluxes from the corn field in the arid region.

关 键 词：涡度相关 平均周期 能量通量 

分 类 号：S513[农业科学—作物学]