1981-2019年鄱阳湖流域潜在蒸散变化特征及气候成因分析  

Variation characteristics and cause analysis of potential evapotranspiration in Poyang Lake Basin from 1981 to 2019

作　　者：秦晓晨 戴志健 陈兴鹃 李柏贞 占明锦 Qin Xiaochen;Dai Zhijian;Chen Xingjuan;Li Bozhen;Zhan Mingjin(Eco-meteorological Centre of Jiangxi Province,Nanchang 330096,China;Climate Change Centre of Jiangxi Province,Nanchang 330096,China)

机构地区：[1]江西省生态气象中心,南昌330096 [2]江西省气候中心,南昌330096

出　　处：《农业工程学报》2021年第7期94-102,共9页Transactions of the Chinese Society of Agricultural Engineering

基　　金：江西省自然科学基金(20202BABL203036);江西省气象局气象科技项目(JX2020Q09)。

摘　　要：为探明鄱阳湖流域潜在蒸散的变化特征,揭示不同季节潜在蒸散趋势差异及其气候成因,该研究基于1981-2019年鄱阳湖流域74个气象站点的逐日气象资料,利用Penman-monteith公式计算各站点逐日潜在蒸散量( ET_(0)),结合敏感性-贡献率法,分析了1981-2019年鄱阳湖流域 ET_(0)在年、季尺度上的变化趋势及其主导气候因子。结果表明:1)1981-2019年鄱阳湖流域年尺度 ET_(0)具有先降后升的特点,21世纪以前呈下降趋势,进入21世纪后下降趋势减弱,并在21世纪头10年后半段转为上升趋势。整体上,鄱阳湖流域 ET_(0)呈显著增加趋势(1.50 mm/a,P<0.05),其中春季增加速率最快(0.81 mm/a,P<0.05),秋季次之(0.64 mm/a,P<0.05),冬季和夏季分别呈不显著增加和下降趋势(P>0.05);2)最高气温升高是年均 ET_(0)和春、秋季 ET_(0)增加的主导因子,冬季 ET_(0)增加的主导因子为最低气温的升高,而辐射下降是夏季 ET_(0)下降的主导因子;3)不同气象要素贡献率的年代际变化分析表明,鄱阳湖流域年均 ET_(0)由降转升的原因是2000年以后气温增加的正贡献超过风速和辐射下降的负贡献。该研究对鄱阳湖流域农田水分管理和季节性干旱监测具有重要意义。Potential evapotranspiration( ET_(0))is an essential indicator to determine the level of climate dryness and water shortage,particularly for crop water demand and irrigation.Recent studies have found that the ET_(0) in most areas of China changed from a downward trend to an upward trend in the early 1990s,closely relating to the tendency of meteorological factors.Seasonal water deficit has been the main limiting factor for agricultural production in summer and autumn,especially in Poyang Lake Basin(PLB),one of the most important commodity grain bases in China.However,the ET_(0) trend and the seasonal differences still remain unclear.In this study,a Penman-monteith formula was utilized to calculate the ET_(0) in PLB during 1981-2019 using the daily observed data from 74 meteorological stations.Mann-Kendall trend test and the sensitivity-contribution method were applied to reveal the trend of ET_(0) on an annual and seasonal scale,and thereby to compare the contribution rates of climate factors,including the wind speed,solar radiation,vapor pressure,as well as the minimum and maximum temperature.Results showed that:1)The annual ET_(0) in the PLB first declined and then rose during the study period,where a downward trend was found before 2000s followed by a weak downward trend after 2000 s,and an upward trend in the second half of 2000s.The ET_(0) showed an increasing trend in other seasons except for summer and the annual scale in 1981-2019.The annual trend of ET_(0) was 1.50 mm/a(P<0.05),with the highest increasing rate in spring(0.81 mm/a,P<0.05)followed by autumn(0.64 mm/a,P<0.05).While the summer ET_(0) experienced a decreasing trend(-0.23 mm/a,P>0.05).2)The ET_(0) reduced by 3.97%in 1981-2019,with the decrease in wind speed and solar radiation,while the increase in the water vapor pressure.Nevertheless,the cumulative contribution rate of the minimum and the maximum temperature was 9.79%,which ultimately increased ET_(0) by 5.84%.Therefore,the warming temperature was the main reason for the annual increase of E

关 键 词：蒸散 气候 季节 时空变化 贡献率 鄱阳湖流域 

分 类 号：P426.21[天文地球—大气科学及气象学]