松山自然保护区蒸发量和降水量的变化特征及其原因分析

Change Characteristics of Evaporation and Rainfall in Songshan Nature Reserve and Their Causes

为了研究北京松山自然保护区的水分循环变化规律,利用松山气象观测站1971—2011年共41年的降水量、温度、日照时数和蒸发量等观测资料,对松山蒸发量和降水量的月、季节、年的变化特征,以及各气象因子与蒸发量之间的相关关系进行分析。结果表明:松山自然保护区的蒸发主要集中在4—6月,降水主要集中在7—8月;41年的蒸发量、降水量分别以约27mm/10a、5mm/10a的速率呈下降趋势;各月、各季节及各年的蒸发量均明显大于降水量;从月、季节的分布来看,蒸发量与日照时数、温度均为极显著正相关,两因素对蒸发量的影响次序均为:温度>日照时数;从年的分布来看,蒸发量受日照时数和温度的影响不显著。

In order to study the variation of water cycle of Songshan Nature Reserve, 41 years observational data in Songshan meteorological station from 1971 to 2011, which includes rainfall, temperature, sunshine hours and evaporation were used. The change characteristics of monthly, seasonal, yearly evaporation and rainfall and relationships between evaporation and other meteorological elements were studied. The results indicated that： the evaporation mostly occurred from April to June and the rainfall mostly occurred from July to August. The evaporation trend and the rainfall trend decreased from 1971 to 2011 with an average rate of 27 mm per 10 years and 5 mm per 10 years, respectively. The evaporation was obviously more than the rainfall under monthly, seasonal and yearly distribution. Sunshine hours and temperature were very significantly correlated with monthly evaporation and seasonal evaporation, with the order of temperature〉sunshine hours. Yearly evaporation had no significant influence with sunshine hours and temperature.