摘要
蒸散发是若尔盖高原湿地重要的水文过程,但目前缺乏对若尔盖地区实际蒸散发量的相关研究结果。为计算若尔盖高原实际蒸散量,利用1967—2011年若尔盖高原地区红原、玛曲和若尔盖3个地面气象站的逐日气象资料,应用FAO56推荐的Penman-Monteith(P-M)公式,依据单作物系数法计算若尔盖地区实际蒸散量,利用累积距平、Mann-Kendall趋势检验、回归分析等方法分析其变化规律。结果表明,草地蒸散量是若尔盖高原实际蒸散量的主要构成部分,草地蒸散量达362.3mm·a-1,占74.28%。湿地蒸散量为116.6 mm·a-1,占23.85%;近45年来若尔盖高原3个气象站的ET_c显著相关,ET_c平均值为488.6 mm·a^(-1)。ET_c的变化并不明显,呈缓慢增加趋势,绝对变率为12.75 mm,相对变率为2.62%。若尔盖高原ET_c变化与植被生长周期密切相关,高强度蒸散过程集中在短暂的夏季,7月份平均值达3.73 mm·d^(-1)。4、10月份气温低于0℃,ET_c为1.5~2.0 mm·d^(-1);通过回归分析得出ET_c与气象因子间的关系式,相关系数r>0.9,P<0.05,相对误差均低于0.6%;年ET_c与年均气温相关性达到0.01的显著性水平,年ET_c与年降水量、相对湿度呈负相关性;1968—1971年ET_c增加36.09 mm,相对降水量增加5.82%;1971—1981、1981—2005年ET_c分别减少12.22 mm和16.34 mm;2005—2011年ET_c增加41.75 mm,相对降水量增加6.41%。该地区水文过程中蒸散发相对于水分补给变化较小。
Evapotranspiration is an important hydrological process in the Zoige Plateau,but it lacks the results of the relevant studieson the actual evapotranspiration in this area.In order to calculate the actual evapotranspiration of the Zoige Plateau,thePenman-Monteith(P-M)formula recommended by FAO56was used to select the single crop coefficient from the dailymeteorological data of the three ground meteorological stations in Hongyuan,Maqu and Zoige from1967to2011.Based on thesingle crop coefficient method,the actual evapotranspiration in the Zoige Plateau was calculated,and the change rule was analyzedby the method of cumulative anomaly,man-kendall trend test and regression analysis.The results showed that the evapotranspirationof grassland was the main component of the actual evapotranspiration of the Zoige Plateau.The evapotranspiration of grassland was362.3mm·a-1,accounting for74.28%.The evapotranspiration of wetland was116.6mm·a-1,accounting for23.85%.In the past45years,the ETc of the three weather stations was significantly correlated,and the mean ETc of the Zoige Plateau was488.6mm.Changes in ETc is not obvious;was slowly increasing trend.Absolute variability12.75mm,and the relative variability of ETcwas2.62%.Changes of ETc in the Zoige Plateau was closely related to the plant growth stage.The high intensity evapotranspirationprocess was concentrated in the short summer.ETc reached a peak of3.73mm·d-1in July.April and October temperature was below0℃,decreased to1.66mm·d-1and1.52mm·d-1.The expression of ETc equation was obtained by regression analysis,r>0.9,P<0.05,and the relative error was less than0.6%.The correlation between ETc and annual mean temperature was0.01,and the annual ETcwas negatively correlated with annual precipitation and relative humidity.In the four stages,corresponding to1968,1971,1981,2005and2011,in the first stage ETc increased by36.09mm,increased by5.82%relative to annual precipitation.In the second andthird stage ETc decreased by12.22mm and16.34mm,respectively.And the fourth stage E
作者
李志威
孙萌
游宇驰
余国安
LI Zhiwei;SUN Meng;YOU Yuchi;YU Guoan(School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410114, China;State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China;Key Laboratory of Water-Sediment Sciences and Water Disaster prevention of Hunan Province, Changsha 410114, China;Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China)
出处
《生态环境学报》
CSCD
北大核心
2017年第8期1317-1324,共8页
Ecology and Environmental Sciences
基金
省部共建三江源生态和高原农牧业国家重点实验室开放研究项目(2017-KF-01)
国家自然科学基金项目(91547112)
青海省科技厅项目(2016-ZJ-Y01)
