KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY，CAS
| 中国天山典型流域径流组分特征及水汽来源研究 | |
| Alternative Title | Runoff composition separation and water vapor source identification in typical catchments in Tianshan, China |
| 陈海燕 | |
| Subtype | 博士 |
| Thesis Advisor | 陈亚宁 |
| 2019-06-30 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 北京 |
| Degree Discipline | 理学博士 |
| Keyword | 中国天山 氢氧稳定同位素 降水水汽来源 蒸发分馏 径流组分 Tianshan Mountains in China Stable Hydrogen and Oxygen Isotopes Water Vapor Source of Precipitation Evaporation Fractionation Stream Flow Components |
| Abstract | 作为水分子的一部分，氢氧稳定同位素是研究水循环的稳定而客观的示踪剂。天山山脉作为西北干旱区中的“湿岛”，是新疆重要的水资源形成区与存储区。研究天山地区的水循环特征对于应对气候变化带来的不利影响、预测区域未来水资源变化趋势具有重要的指导意义。然而，数据不足是天山地区水循环研究的主要限制因素。 本文以中国天山北坡的乌鲁木齐河、玛纳斯河和南坡的开都河、黄水沟以及阿克苏河等典型流域为研究靶区，采用同位素水文学方法，研究了水资源构成，解析了径流组分，分析了气候变化背景下的中国天山地区水汽来源、蒸发分馏对降水、地表水和地下水的影响。本文的主要结论如下：（1） 天山降水 δ18O 与 δ2H 冬季低，夏季高； d-excess 夏季变化幅度小，冬季变化幅度大。 δ18O 与气温、水汽压呈显著的正相关关系，与相对湿度呈显著的负相关关系。由于云下二次蒸发的影响，红沟与肯斯瓦特站的 LMWL 的斜率与截距都小于 GMWL。天山南北坡河水同位素组成没有显著的差异。河水同位素组成的季节变化远小于降水。 不同流域、不同季节，河水同位素组成随环境因子的变化而不同。南坡河水蒸发线的斜率和截距均高于北坡。地下水同位素组成与流域平原区河水同位素组成相近，表明河水与地下水的交互作用频繁。开都河与阿克苏河地下水同位素组成都没有显著的季节变化。受蒸发分馏的影响，平原区地下水的斜率和截距都显著低于 LMWL 与 GMWL。（2） 不同径流组分对径流的贡献具有显著的时空差异性。 由于天山降水主要集中于夏季， 降雨对典型融冰期（9% - 23%） 的贡献率高于典型融雪期（5% -9%）。基流对六个典型流域的平均贡献率为 56%，是天山地区径流的最主要补给来源（30% - 75%）。基流对天山北坡（57%） 的贡献低于天山南坡（63%）；在典型融冰期，基流对天山北坡（52%） 的贡献高于天山南坡（44%）。季节性积雪融水或冰川融水对径流的贡献具有显著的空间变异性。在典型融雪期，季节性积雪融水对径流的贡献率的变化范围为 22% - 49%。在典型融冰期，冰川融水对径流贡献率的变化范围为 12% - 59%。积雪融水对天山北坡（36%） 的贡献高于天山南坡（31%）；冰川融水对天山南坡（42%） 的贡献高于天山北坡（36%）。由于南坡降水较少，南坡比北坡更加依赖于冰川融水的补给。 季节性积雪融水或冰川融水对径流的贡献与流域最大积雪面积比或流域冰川面积比呈正相关关系。（3） 森林带与草原带的外来水汽主要来源于亚欧大陆再循环水汽和黑海-里海蒸发水汽。 再循环水汽对森林带与草原带的贡献具有显著的季节变化特征，除春季外，蒸发水汽对森林带的贡献低于草原带。 植物蒸腾主要发生于夏季，蒸腾水汽对森林带降水的贡献（5.35%） 高于对草原带降水的贡献（3.79%）。 下垫面特征与气温是影响再循环水汽比的主要因子。降水水汽来源对天山北坡森林带与草原带的降水同位素组成没有显著的影响。（4）天山降水 d-excess 变化量 d 与蒸发剩余比之间存在-1.09‰/%的线性关系。 降水量越大、相对湿度越高、 气温越低、 雨滴半径越大，雨滴蒸发剩余比越高，d-excess 变化量越小，二者之间的线性关系越显著，斜率越低，斜率小于-1‰/%。反之，降水量越小、相对湿度越低、 气温越高、 雨滴半径越小，雨滴蒸发剩余比越低，d-excess 变化量越大，二者的线性关系越弱，斜率越高，斜率往往高于-1‰/%。乌鲁木齐河与开都河上游山区河水的蒸发剩余比没有显著的季节变化（82% -86%），其他流域河水都是夏季蒸发剩余比显著高于春秋季。尽管天山南坡的气温高于北坡，但南北坡河水蒸发剩余比没有显著的差异，北坡河水的平均蒸发剩余比为 84%，南坡为 83%。天山南北坡河水及河水蒸发水汽的 δ18O 与 δ2H 没有显著的区域差异，季节变化特征也相似，表明南北坡水循环过程相似。 夏秋季，开都河与阿克苏河地下水的蒸发剩余比相近，开都河地下水春季蒸发剩余比高于阿克苏河。 蒸发前后，地下水的 δ18O 与 δ2H 都没有显著的区域差异，表明天山南坡的地下水具有相似的水循环过程。 |
| Other Abstract | As a part of water molecule, stable oxygen (O18) and hydrogen (H2) isotopes arestable and objective teacers for water cycle studying. Honoured as ‘water tower’ ofarid region of northwest China, Tianshan is important water source for Xinjiangprovince. Water cycle process studying in the Tianshan Mountains is of greatimportance to forcast the regional water resource change trend in the future and todeal with the adverse effect of climate change. However, lacking of reliable data hasbecome the major limiting factor for water cycle process studying in the TianshanMountains. In this study, based on stable oxygen and hydrogen isotopes in surfacewater and groundwater, the vapor source of precipitation, the effect of evaporationfractionation on stable isotopes and the contribution of stream flow components werestudied in the typical catchments in south slope (Kaidu River Basin, HuangshuigouRiver Basin, and Akesu River Basin) and north slope (Urumqi River Basin andManasi River Basin) of Tianshan Mountains. The main results are as following:(1) The values of δ18O and δ2H in precipitation are higher in summer than inwinter. The range of d-excess is larger in winter than in summer. The variation of δ18Oin precipitation is positively correlated with temperature and vapour pressure, whilenegatively correlated with relative humidity. Due to the effect of sub-cloudevaporation, the slopes of LWML at the Honggou station and Kensiwate station arelower than GMWL. There is no significant difference between values of δ18O and δ2Hin stream water in the north slope and south slope. The seasonal variations of δ18O andδ2H values in stream water are significantly lower than precipitation. The effects ofenvironment factors on stable oxygen and hydrogen isotopes are different in differentcatchments and different seasons. The slopes and intercepts of evaporation lines ofstream water in north slope are lower than south slope. The δ18O and δ2H values ingroundwater are similar to stream water, indicating the frequent interaction betweenstream water and groundwater. The δ18O and δ2H values in groundwater in differentcatchments are similar and without significant seasonal variation. Due to the effect ofevaporation fractionation, the slope and intercept of groundwater are lower thanLMWL and GMWL.(2) The contribution of rainfall to stream flow is higher in typical glacier meltperiod than typical snow melt period. The contribution ratios of rainfall range from 5% to 9% in the typical snow melt period, and range from 9% to 23% in the typicalglacier melt period. Baseflow is the most important contributor (30% - 75%) to streamflow in the Tianshan Mountains, with an average contribution ratio of 56% in the sixbenchmark catchments. The mean contribution ratio of baseflow is lower in the northslope (57%) than south slope (63%) of the Tianshan Mountains during typical snowmelt period. While during typical glacier melt period, the contribution ratio ofbaseflow is higher in the north slope (52%) than south slope (44%) in the TiansahnMountains. There are significant spatial variations of the contribution ratios ofseasonal snow meltwater and glacier meltwater. The contribution ratios of seasonalsnow meltwater to stream flow range from 22% to 49% during typical snow meltperiod. The contribution ratios of glacier meltwater to stream flow range from 12% to59% during typical glacier melt period. The mean contribution ratio of seasonal snowmeltwater is higher in the north slope (36%) than south slope (31%). The meancontribution ratio of glacier meltwater is higher in the south slope (42%) than northslope (36%). With less precipitation in the south slope than north slope of theTianshan Mountains, the river runoff in the south slope depend more on glaciermeltwater than north slope. The contribution ratios of seasonal snow meltwater orglacier meltwater to stream flow are positively correlated with the maximum snowcover ratios and glacier area ratios in the catchment.(3) The vapor sources of precipitation are mainly come from evaporation vaporfrom the Eurasia and evaporation vapor from the Black Sea and Caspian Sea. Thereare significant seasonal variations of the contributions of recycled vapor toprecipitation in forest areas and in grassland areas. The contribution ratios ofevaporation vapor to precipitation are higher in forest areas than grassland areasexcept in spring. Summer is the most important season for plant transpiration. Thecontribution of transpiration vapor to precipitation is higher to forest areas (5.35%)than to grassland areas (3.79%). The characteristics of the underlying surface andtemperature are the most important factors that influence the contributions of recycledvapor to regional precipitation. There is no significant effect of vapor source onprecipitation isotopes in the Tianshan Mountains.(4) Due to the effect of evaporation, the variation of d-excess in precipitation( d ) and residual ratios of raindrops after evaporation are linerly correclated, with aslope of -1‰/%. With lower temperature, lager precipitation, higher relative humidityand larger raindrops, the residual ratios of raindrops after evaporation are higher, the variation of d-excess in precipitation are lower, the liner relationships betweenresidual ratios of raindrops after evaporation and variation of d-excess in precipitationare more significant, the slopes are lower, even lower than -1‰/%. On the contrary,with higher temperature, lower precipitation, lower relative humidity and smallerraindrops, the residual ratios of raindrops after evaporation are lower, the variation ofd-excess in precipitation are higher, the liner relationships between residual ratios ofraindrops after evaporation and variation of d-excess in precipitation are weaker, theslopes are higher, often higher than -1‰/%. There were no significant seasonalvariation of residual ratios (82% - 86%) in stream water in the Urumqi River Basinand Kaidu River Basin. In other basins, residual ratios in stream water are higher insummer than in spring and autumn. Though the temperature is higher in the southslope of the Tianshan Mountians than the north slope, there were no significantdifference between residual ratios of stream water in the south slope and north slope.The mean residual ratio of stream water is 84% in the north slope, and 83% in thesouth slope. The spatial variations of δ18O and δ2H in stream water before and afterevaporation and in evaporation vapour from stream water were similar in the northslope and south slope of the Tianshan Mountains. The seasonal variations of δ18O andδ2H in stream water before and after evaporation and in evaporation vapour fromstream water were also similar in the north slope and south slope of the TianshanMountains, indicating that the water cycle processes are similar in the north slope andsouth slope. In summer, the residual ratios of groundwater are similar in the KaiduRiver Basin and Akesu River Basin. In spring, the residual ratios of groundwater inthe Kaidu River Basin are higher than the Akesu River Basin. There are no significantspatial variations of δ18O and δ2H in groundwater before and after evaporation,indicating the similar water cycle processes in the Tianshan Mountains. |
| Subject Area | 自然地理学 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xjlas.org/handle/365004/15380 |
| Collection | 中国科学院新疆生态与地理研究所 研究系统 |
| Affiliation | 中国科学院新疆生态与地理研究所 |
| First Author Affilication | 中国科学院新疆生态与地理研究所 |
| Recommended Citation GB/T 7714 | 陈海燕. 中国天山典型流域径流组分特征及水汽来源研究[D]. 北京. 中国科学院大学,2019. |
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