内蒙古农田潜在蒸散量敏感系数时空分布规律研究

Time-space distribution rule study of farmland potential evapotranspiration sensitivity coefficient in Inner Mongolia

为了得出对潜在蒸散量(ET0)影响最大的气象因子,选择内蒙古自治区8个气象站点1961~2013年长时间逐日气象数据,利用Penman-Monteith(P-M)公式计算8个站点逐日ET0,并基于无维偏导数法计算了不同气象因子的敏感系数,对其年际、年内和空间变化趋势进行了分析,结果表明:内蒙古区平均温度的变化趋势最大,且不同站点正负取值不同,风速敏感系数呈自西南到东北逐渐降低趋势,日照敏感系数呈中部最高,两侧逐渐减小趋势,而相对湿度敏感系数呈自西南到东北逐渐升高趋势,对内蒙古ET0影响最大的气象因子为相对湿度,风速次之,日照和平均温度的影响较小。

In order to study the meteorological factor with the maximum influence on potential evapotranspiration(ET0),the daily ET0 of eight meteorological stations in Inner Mongolia Autonomous Region were calculated with Penman-Monteith(P-M)formula and with the daily meteorological data from 1961 to 2013.The sensitivity coefficients of various meteorological factors were calculated based on non-dimensional partial derivative method.The inter-annual,annual and space change trends were also analyzed.The results of calculation and analysis demonstrate that in Inner Mongolia Autonomous Region,average temperature has the maximum change trend with negative or positive value at various stations;the wind velocity sensitivity coefficient gradually decreased from Southwest to Northeast;sunshine sensitivity coefficient in the middle is the highest and gradually drop toward both sides;relative humidity sensitivity coefficient gradually rise from Southwest to Northeast;relative humidity is the meteorological factor with the maximum influence on ET0 of Inner Mongolia and followed by wind velocity.Sunshine and average temperature render relatively small influence.