长武县1979——2008年水面蒸发量与温度、降水量关系通径分析

Path Analysis of Water Surface Evaporation with Temperature and Precipitation:Changwu from 1979 to 2008

为了揭示各气象因子对于水面蒸发量的影响,并找出影响水面蒸发量的主要气象因素。笔者先后采用相关分析和通径分析法,对长武县1979—2008年蒸发量及相关气象因子进行统计分析。结果表明:各个气象因子的变异程度在合理范围内,变异系数的大小为:温度(CV=0.06)<水面蒸发量(CV=0.12)<降水量(CV=0.24);各气象因子与水面蒸发量之间存在着相关性,且相关程度为:温度(r=0.930)>降水量(r=0.765);在进一步的通径分析研究中,从直接效应来看,温度对蒸发量的影响较为明显,降水量则相对较小,且呈现一定的副作用;从通径分析的间接效应来看,降水量主要通过平均温度对蒸发量产生影响。降水量对蒸发量的影响主要是通过温度变化起作用,因此,影响水面蒸发量的主导因素是温度变化。

To reveal the effect of meteorological factors on water surface evaporation and determine mainmeteorological factors affecting water surface evaporation, the authors used correlation analysis and pathanalysis to analyze the relationship between water surface evaporation and other meteorological factors during1979-2008 in Changwu. The results showed that： the variation coefficient of each meteorological factor was insuitable scope, which was in the following trend： temperature（CV=0.06） 〈water surface evaporation（CV=0.12） 〈precipitation（CV=0.24）; there were correlations between water surface evaporation and othermeteorological factors, and the correlation coefficients followed an order： temperature（r=0.930）〉precipitation（r=0.765）; as to the direct effect of path analysis, the influence of temperature on water surface evaporation wasmore significant, while the influence of the precipitation was small, and showed a negative effect; from theperspective of the indirect effect of path analysis, precipitation had effect on evaporation which was mainlyaffected by the average temperature. The influence of precipitation on water surface evaporation was mainlyaffected by temperature which was determined as the main factor.