中文摘要：

利用松嫩平原19个站点的常规气象数据，采用FAO最新推荐的P—M公式计算了松嫩平原2000—2007年的参考作物日蒸散量、月蒸散量及年蒸散量，在此基础上分析了参考作物蒸散量的年际、年内时空变化特征，并探讨了参考作物蒸散量对主要影响因素的敏感性。结果表明：①松嫩平原的多年平均参考作物蒸散量从东北向西南逐渐增加，通榆、白城为全区的高蒸散中心，北安为低蒸散中心；②松嫩平原多年平均参考作物月蒸散量最高值出现在5月，而不是出现在气温最高的7月，最低气温出现在1月；③在参考作物蒸散量的诸多影响因素中，日最高气温、日平均相对湿度的影响最为明显，其次是日平均风速与日照时数，日最低气温与高程对参考作物蒸散量的影响很小，几乎可以忽略。图8，表2，参15。关键词：松嫩平原；参考作物蒸散；Penman—Monteith公式；敏感性分析

英文摘要：

Daily, monthly and yearly reference evapotranspiration over Songnen Plain from 2000a to 2007a were calculated by using nor- mal meteorological data of 19 stations and Penman-Monteith equitation newly recommended by FAO. Temporal and spatial characteris- tics of reference evapotranspiration were analyzed and the sensitivity to main ＇affecting factors was explored. The results showed that ： （1） the multiyear＇ s average of yearly reference evapotranspiration gradually increased from the northeast to the southwest, Tongyu, Baicheng were the high evapotranspiration center and Bei＇ an was the low center; （2）the highest multiyear＇ s average of monthly refer- ence evapotranspiration of Songnen Plain was not in July though it owed the highest air temperature but in May, and the highest muhi- year average of monthly reference evapotranspiration was in January; （3）daily maximum air temperature and daily average relative hu- midity were the most influential factors among all the affecting factors, then were daily average wind speed, and daily minimum air tem- perature and elevation played too little influence to even would be ignored.