1957—2012年中国参考作物蒸散量时空变化及其影响因子分析

根据1957—2012年全国608个气象站的逐日气象资料,利用Penman-Monteith公式计算作物潜在蒸散量,对全国及水资源一级分区潜在蒸散量时空分布特征、变化趋势进行分析;基于Arc GIS及SPSS软件,采用主成分分析方法,对潜在作物蒸散量的影响因子及其分布特征进行探讨。结果表明:近56 a来,全国年潜在蒸散量在616~2 128 mm之间,河西走廊、南部岭南地区、海南岛以及华南沿海作物潜在蒸散量较大,而在黑龙江一带、四川盆地及西南地区东部,潜在蒸发量较小。各分区年均潜在蒸发量均呈现减少趋势,西北诸河区倾向率最大,为-12.22 mm/10 a;影响潜在蒸散量的因子中,第1主成分为热力学因子,第2主成分为水分因子和辐射因子,第3主成分为地理因子和空气动力学因子,第4主成分为高程因子。

Temporal and Spatial Changes of Potential Evapotranspiration and Its Influencing Factors in China from 1957 to 2012

According to daily meteorological data of 608 weather stations in China from 1957 to 2012, the thesis analyzes the temporal and spatial changes and trends of the potential evapotranspiration (ET₀) in China using Penman-Monteith formula. Based on ArcGIS, SPSS and principal component analysis, this paper discusses the distribution characteristics and influencing factors of ET₀. The results show that in the 56 years the average annual ET₀ is between 616 and 2128 mm with the average of 1104 mm, and the highest value is 3.45 times of the lowest. In the Hexi Corridor, South of the Five Ridges, Hainan Island and the coastal area of southern China, ET₀ is comparatively larger; however, in the northeast region of Heilongjiang, Sichuan basin and the east region of the southwestern area, ET₀ is smaller. The ET₀ of ten hydrological regions indicates decline trend, and the rate of the Northwest Rivers region is -12.22 mm/10 a. The rate of Haihe, Liaohe, Huaihe, Yangtze region is -9.15, -9.11, -8.02, -5.44 mm/10 a respectively. In Huanghe, Southeast, Southwest, Songhua regions, the decline rate is comparatively smaller. The interannual fluctuation in Huanghe and Southwest Rivers region is sever. The peak and minimum value appears in different month in ten regions. The maximum appears in July in Northwest Rivers, Huanghe, Southeast Rivers, Yangtze and Zhujiang regions, in May in the Southwest, Liaohe, Songhua, Haihe regions, while in June in Huaihe regions. Among influencing factors of ET₀, the first principal component is the thermodynamic factor, the second principal component is the moisture and radiation factor, the third component is constitute of the geographic and aerodynamic factors, and the elevation factor composes the fourth.