中文摘要：

基于2003年1月长江干流径流同位素同步监测资料,分析了径流同位素与大气降水同位素^18O和D相对丰度之间的关系,探讨了^18O相对丰度和氘盈余（Ed）的空间变化规律.分析结果表明：长江干流径流同位素时程变化主要受降水同位素季节变化的影响;区域降水同位素场是长江干流径流同位素^18O和D相对丰度空间变化的主要影响因素;长江流域湖泊或水库蒸发效应是导致长江干流径流重同位素沿程富集的主要因素之一;监测期间长江流域上中游蒸发较为强烈,中游区蒸发最强烈,下游区蒸发变化剧烈.

英文摘要：

Based on isotopic synchronous monitoring data of runoff of the main stem of Yangtze River in January of 2003, the relationship between the ^18O of runoff and atmospheric precipitation isotope and D was analyzed. The spatial variation of ^18O and excess deuterium （Ed） are discussed. The analytic results show the following： the temporal and spatial variation of the runoff isotopes of the main stem of the Yangtze River are mainly affected by seasonal precipitation isotopes; the main factors in the spatial variation of ^18O and D are the isotopic fields of regional precipitation; the evaporation effect of lakes and reservoirs in the Yangtze River basin is one of the main factors in its isotopic influx; and, during the monitoring period, the evaporation in the upper and middle reaches of the Yangtze River was high, especially in the middle reaches, and the variation of the evaporation in the lower reaches was large.