中文摘要：

为了有效评估平衡分馏模式和动力分馏模式模拟水稳定同位素分馏的合理性,开展了不同大气条件下的蒸发皿蒸发实验和2种模式的模拟试验,实验与模拟结果表明：随着蒸发的进行,蒸发皿剩余水体中稳定同位素不断富集,同位素的分馏速率与蒸发速率成正比,并表现出夏季高、冬季低的特点;但在降水发生时段,蒸发水体稳定同位素容易受到相对湿度和大气水汽稳定同位素的影响,出现贫化现象.受到温度和相对湿度等蒸发条件的影响,实测蒸发线斜率呈现夏季低、冬季高的特点.4次实验剩余水体中的过量氘随着剩余水比率（f）的变化总体上呈下降趋势,降水时段的过量氘出现上升现象.在模拟试验中,与平衡模拟结果相比,动力模拟再现水体蒸发过程中稳定同位素变化的能力更强,能体现出实际蒸发过程中水稳定同位素比率随f变化的细节;动力模拟的蒸发线更能反映实际蒸发过程;过量氘的动力模拟值更接近实测值的大小及其变化趋势.

英文摘要：

To assess the results of water stable isotopes fractionation simulated respectively by equilibrium model and kinetic model, four evaporation experiments were conducted under different atmospheric conditions. The results indicate that stable isotopes in residual water are gradually enriched along with the evaporation, there is a positive correlation between the enrichment rate and the evaporation rate. However, when precipitation happens, the residual water stable isotopes are diluted, as they are susceptible to the influence of relative humidity and the stable isotopes in atmospheric water vapor. Experimental water stable isotope fractionation rate is influenced by temperature and relative humidity, and certain positive correlation between the isotopic fractionation rate and the temperature changes appears. This phenomenon is contrary to the results described by Rayleigh fractionation model. There is a remarkable inverse relationship between the isotopic fractionation rate and relative humidity. Although the simulation results of equilibrium fractionation model have higher correlation coefficient with the measured results,as a whole,they fail to reflect the details of changes in stable water isotopes ratio with f in actual evaporation process, especially during the middle period of evaporation.In addition, the results of equilibrium simulation overestimate the degree of stable isotope fractionation. By contrast, kinetic fractionation model performs well in reproducing the variation of stable isotopes in water evaporation. It can capture the details of changes of the δ18O. The actual evaporation line slopes （3.855, 3.749, 4.097, 6.942） are low in summer and high in winter due to the influences of air temperature and relative humidity. Evaporation line slopes calculated from equilibrium fractionation model remain near 8, and their intercepts are all more than 10, close to the global meteoric water line, reflecting a poor fitting result. However, the evaporation line slopes （4.265, 3.433, 5.705, 5.833） of k