摘要
以昆山试验站2012-2013年自动气象站观测的小时气象资料为依据,分别采用ASCE PM公式和FAO56PM公式计算小时ET_0,在对比两种小时ET_0计算结果基础上,通过逐小时累积求和得到日ET_0值(分别记作ET_(0-dhA)和ET_(0-dhF)),进而与日尺度参照作物腾发量ET_0(记作ET_(0-d))进行对比,在明确ET_(0-d),ET_(0-dhA)和ET_(0-dhF)差异的基础上,分析了基于不同ET_0确定的水稻单作物系数差异(分别记为K_(c-d)、K_(c-dhA)与K_(c-dhF))。结果表明:在水稻不同生育阶段内,小时ET_0值大致呈抛物线型日变化,在中午时ET_0达到最大,午夜则最低; 2种PM公式计算得到的小时ET_0值存在微小差异,差异范围在-0. 02～0. 5 mm/h内,白天ASCE PM公式计算值偏大,夜间则无明显规律。在日尺度上,ET_(0-d),ET_(0-dhA)和ET_(0-dhF)三者之间具有良好的线性关系,大小关系表现为:ET_(0-dhA)> ET_(0-d)> ET_(0-dhF)。总体上,由实测日腾发量ET_a求得的节水灌溉水稻单作物系数大于按照FAO推荐方法确定的作物系数值,且采用不同日ET_0计算结果得到的水稻K_c值之间的大小关系为:K_(c-dhA)<K_(c-d)<K_(c-dhF),但其差异较小,差异程度在5%以内。
Based on the hourly meteorological data collected by an automatic meteorological station in Kunshan Experimental Station during 2012-2013,hourly ET0 were calculated by ASCE PM and FAO56 PM formulas equations separately to show the difference in hourly ET0 calculated by two different equations. Then the hourly ET0 were summed up to obtain the daily ET0 ( termed as ET0-dhA and ET0-dhF) and compared to the daily ET0 calculated by PM equation at daily scale( ET0-d). Differences among ET0-d,ET0-dhA and ET0-dhF were discussed,as well as the difference among the single crop coefficient of rice based on daily ET0 determined by different procedures. The results showed that hourly ET0 varied in parabolic shape,with the maximum observed at noon and minimum at midnight. Hourly ET0 were slightly different between two methods,with the difference fell in range of -0. 02 ~ 0. 5 mm/h. Hourly ET0 by ASCE PM were found slightly higher than by FAO56 PM in daytime. Daily ET0 were highly correlated to each other,and ranked in sequence of ET0-dhA> ET0-d> ET0-dhF. Local calibrated single crop coefficient Kc of rice were higher than the value determined following the procedure by FAO,and ranked in sequence of Kc-dhA< Kc-d< Kc-dhF,with the difference among them less than 5%.
作者
王可纯
蔡少杰
卫琦
吕玉平
廖林仙
徐俊增
WANG Kechun;CAI Shaojie;WEI Qi;Lu Yuping;LIAO Linxian;XU Junzeng(Key Laboratory of Efficient Irrigation-Drainage and Agricultural Soil-Water Environment in Southern China,Hohai University,Nanjing 210098,China;State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China)
出处
《水资源与水工程学报》
CSCD
2019年第1期247-253,共7页
Journal of Water Resources and Water Engineering
基金
江苏水利科技项目(2015089)
关键词
ASCE
PM公式
FAO56
PM公式
不同时间尺度
参考作物腾发量
作物系数
水稻
ASCE penman-monteith formula
FAO56 penman-monteith formula
different temporal scales
reference crop evapotranspiration
crop coefficients
rice
