第二松花江流域潜在蒸散发时空变化及其影响因素
陈海芳1,杨国范1,林茂森1,吴家兵2,3,袁凤辉2,3

(1.沈阳农业大学 水利学院,沈阳 110866; 2.中国科学院 沈阳应用生态研究所,沈阳 110016; 3.中国科学院 森林生态与管理重点实验室(沈阳应用生态研究所),沈阳 110016)

第二松花江流域; 潜在蒸散发; Penman-Monteith法; 时空分析

Spatiotemporal Changes and Affecting Factors of Potential Evapotranspiration in the Second Songhua River Basin
CHEN Haifang1,YANG Guofan1,LIN Maosen1,WU Jiabing2,3,YUAN Fenghui2,3

(1.College of Water Conservancy,Shenyang Agricultural University,Shenyang 110866,China; 2.Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,China; 3.CAS Key Laboratory of Forest Ecology and Management,Institute of Applied Ecology,Shenyang 110016,China)

the Second Songhua River Basin; potential evapotranspiration; Penman-Monteith method; spatiotemporal analysis

备注

潜在蒸散发(ET0)是区域水文循环和能量平衡的重要环节,也是估算实际蒸散、评价生态环境和合理规划水资源的关键因子,分析ET0时空变化规律及主要影响因素在研究水资源对气候变化响应方面具有重要意义。以第二松花江流域内及其周边11个气象站点1978—2018年逐日实测气象资料为数据基础,采用Penman-Monteith法,Mann-Kendall非参数趋势检验法、Kriging插值法、逐步回归分析法和偏相关分析法对比分析了近41年该流域平原区和山区ET0时空变化及其主要影响因素。结果表明:(1)第二松花江流域1978—2018年平原区多年平均ET0为825.9 mm,呈微弱下降趋势,减小速率为6.99 mm/10 a; 山区多年平均ET0为738.8 mm,呈显著上升趋势,上升速率为10.49 mm/10 a; 夏春两季ET0对第二松花江流域全年ET0贡献最大; 在空间尺度上,年ET0呈由西北向东南逐渐减少的趋势。(2)研究区近41 a气温(平均、最高、最低)显著上升(p<0.01),日照时数、风速和相对湿度呈下降趋势; 季尺度上,除秋季平原区相对湿度呈微弱上升趋势,其余气象因子的变化趋势与全年一致。(3)日照时数和风速是影响平原区ET0变化的主要因素,相对湿度显著降低是山区ET0变化明显的主要原因; 各气象因子共同作用引起ET0的变化,且气象因子对ET0的影响因季节和地貌类型而异。
Potential evapotranspiration(ET0)is a significant part in regional hydrologic cycle and energy balance,and also a key factor in estimating actual evapotranspiration,evaluating ecological environment and rationally planning water resources. So it is of great significance to analyze spatiotemporal changes and affecting factors of ET0 in studying the response of water resources to climate change. Based on the daily measured meteorological data from 1978 to 2018 at 11 meteorological stations in and around the Second Songhua River Basin,mathematical statistics method,such as Penman-Monteith method,Mann-Kendall method,Kriging interpolation method,stepwise regression analysis method and partial correlation analysis method,were used to analyze the spatiotemporal changes and affecting factors of ET0 in the plain area and mountain area of the basin in recent 41 years. The results show that:(1)in the Second Songhua River Basin from 1978 to 2018,the ET0 in the plain area showed a slight downward trend,with a climatic tendency rate of 6.99 mm/decade and a multi-year average of 825.9 mm; the ET0 in mountainous areas increased significantly(p<0.01),with a climatic tendency rate of 10.49 mm/decade and a multi-year average of 738.8 mm; summer and spring ET0 contributed the most to the annual ET0 of the Second Songhua River Basin; on the spatial scale,the annual ET0 decreased gradually from northwest to southeast;(2)the temperatured(average,maximum,minimum)of 41 years in the study area increased significantly(p<0.01),and sunshine duration,wind speed and relative humidity decreased; on the seasonal scale,except for the slight rising trend of relative humidity in the plain area in autumn,the change direction of other meteorological factors was consistent with that of the whole year;(3)sunshine duration and wind speed were the main factors affecting ET0 change in plain areas,while the significant decrease of relative humidity was the main reason for the obvious change of ET0 in mountainous areas; the influence of meteorological factors on ET0 changed due to seasons and geomorphologic types.