中文摘要：

中国的大河里的水来源和土壤水分蒸发蒸腾损失总量的同位素的作文很好没被探索。在这调查， < 啜 class= “ a-plus-plus ” > 18 来自中国的主要的大河的水的 O 和 D 价值是综合的在水和 d 过量的同位素理解空间、时间的变化。河水样品在中国从 Changjiang，黄， Songhua，和辽河河的隧道和支流被收集。水从在上游通常从下游的区域相对那与轻同位素被充实。来自 Songhua 河和 Changjiang 河的上面的活动范围的水有相对否定的同位素的价值，分别地由纬度和高度效果影响了。空间模式显示出那 < 啜 class= “ a-plus-plus ” > 18 哦 < 潜水艇 class= “ a-plus-plus ” > 2 河里的 O 价值主要从 9 ～ 7 吗？在大多数中国，基于在光充实的粗略地印射的轮廓，和河，同位素首先在西藏的高原和东北中国位于。从黄和辽河河的线性回归的斜坡建议由直接蒸发的水的损失转移了水的同位素，特别在一些小支流。另外，有一个狭窄的范围低 < 啜 class= “ a-plus-plus ” > 18 哦 < 潜水艇 class= “ a-plus-plus ” > 2 O 由于季风气候的影响相对高流动的季节在低流动的季节期间从河的主要隧道珍视。d 过量价值的不同空间变化都没在中国的河里被发现。然而，在一些河里浇样品，低 d 过量价值高有 < 啜 class= “ a-plus-plus ” > 18 O 价值，在支流显示那蒸发导致了重要的水损失，特别在黄和辽河河的支流。

英文摘要：

Isotopic compositions of the water sources and evapotranspiration in large rivers of China are not well explored. In this investigation, δ18O and δD values of water from major large rivers of China are integrated to understand the spatial and temporal variations in the isotopes of water and d-excess. River water samples were collected from the channels and tributaries of the Changjiang, Yellow, Songhua, and Liao Rivers in China. Water from upstream was generally enriched with light isotopes relative to that from downstream areas. Water from the Songhua River and upper reach of the Changjiang River has relatively negative isotopic values, impacted by latitude and altitude effects, respectively. The spatial pattern showed that δ18O-H2O values in rivers mainly ranged from -9 to -7‰ in most of China based on roughly mapped contours, and rivers enriched in light isotopes were primarily located in the Tibetan Plateau and northeast China. The slopes of linear regression from the Yellow and Liao Rivers suggested that the loss of water by direct evaporation shifted the isotopes of water, especially in some small tribu- taries. Additionally, there was a narrow range of low δ18O- H2O values from the main channel of rivers during the low- flow season relative to the high-flow season due to influence of the monsoon climate. No distinct spatial variation of d-excess values was found in the rivers of China. However, water samples in some rivers with low d-excess values had high δ18O values, indicating that evaporation in the tributaries has led to significant water loss, especially in tributaries of the Yellow and Liao Rivers.