河北省潜在蒸散量变化特征及主导因子辨析

Differentiation and analysis on changing characteristics of potential evapotranspiration in Hebei Province and related dominant factors

潜在蒸散量(ET 0)是地球表面水循环研究及水资源规划管理中重要因素,明确其变化规律及特征对区域水资源利用及农业生产布局有重要意义。根据河北省及周边地区1960-2018年24个典型气象站点逐日气象数据,利用Penman-Monteith模型、偏相关分析、敏感性分析、M-K检验法及空间插值法分析了河北省潜在蒸散量(ET 0)时空分布特征。结果表明:(1)59a来河北省ET 0平均值为1 077.13 mm,平均下降幅度为-2.31 mm/10a,整体呈由西向东、由南向北减少趋势。(2)偏相关分析与敏感性分析表明,RH(平均相对湿度)、WS(风速)和SH(日照时数)对年均ET 0变化影响程度较大;WS、SH与年均ET 0变化趋势一致,而RH与年均ET 0变化趋势相反;RH、HT(日最高气温)、SH是影响ET 0变化的敏感因子,而AT(平均气温)及LT(日最低气温)则为相对不敏感因子。(3)河北省年平均ET 0变化的主导因子为SH,其次为WS;主导因子随季节变化有所差异。春季SH主要影响偏北部地区,WS集中影响中部及偏东部;夏季SH大致影响河北省全境;秋季河北省偏北部地区主要受RH影响,中东部及偏南部地区主要受WS影响;冬季河北省大部分地区受SH影响。研究成果可为河北省水资源的优化配置及农业发展提供一定理论支撑。

Potential evapotranspiration(ET 0)is an important factor in the study of water circulation on the earth surface and in the planning and management of water resources.Based on the daily meteorological data from 24 typical meteorological stations in and around Hebei Province from 1960 to 2018,the temporal and spatial distribution characteristics of the potential evapotranspiration(ET 0)in Hebei Province are analyzed with Penman-Monteith model,partial correlation analysis,sensitivity analysis,M-K test and spatial interpolation method.The results show that the mean value of ET 0 in Hebei Province is 1 077.13 mm in the period of 59 years with a mean decreasing range of-2.31 mm/10a,which overall exhibits a decreasing trend from west to east and from south to north.(2)The partial correlation analysis and sensitivity analysis show that RH,WS and SH have great influences on the mean annual ET 0 change.The trends of WS,SH are coincided with the changing trend of the mean changing trend of ET 0,but the changing trend of RH is opposite to that of the mean annual ET 0.RH,HT and SH are the sensitive factors affecting the change of ET 0,while AT and LT are the relative insensitive factors.(3)The dominant factor of the mean annual change of ET 0 in Hebei Province is SH and then WS.The season-depended changes of the dominant factors are different.In spring,SH mainly affects the northerly region and WS concentrates on the middle and easterly regions.In summer,the whole territory of Hebei Province is generally affected by SH.In autumn,the northerly region of Hebei Province is mainly affected by RH,while the central-eastern and southerly regions are mainly affected by WS.In winter,most parts of Hebei Province are affected by SH.The study result can provide a certain theoretical support for the optimal allocation of water resources and agricultural development of Hebei Province.