scholarly journals Hydrochemical and Stable Isotope Characteristics of Lake Water and Groundwater in the Beiluhe Basin, Qinghai–Tibet Plateau

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2269
Author(s):  
Jinlong Li ◽  
Wei Wang ◽  
Dahao Wang ◽  
Jiaqi Li ◽  
Jie Dong
Keyword(s):  
Stable Isotope ◽  
Lake Water ◽  
Thermal State ◽  
Saturation Index ◽  
Atmospheric Precipitation ◽  
Mineral Dissolution ◽  
Tibet Plateau ◽  
Hydrological Process ◽  
Thermokarst Lakes ◽  
Qinghai Tibet Plateau

Thermokarst lakes are a ubiquitous landscape feature that impact the thermal state, hydrological process, ecological environment, and engineering stability of the permafrost. This study established the hydrochemistry and stable isotope (δ18O and δD) variations of lake water and groundwater in a typical basin located in the central Qinghai–Tibet Plateau (QTP) of China. The results showed that most water samples could be classified as slightly alkaline, with high levels of salinity and hardness, while the dominant water types were HCO3-CO3 and Cl types. Natural hydrochemical processes, such as mineral dissolution, cation exchange, and groundwater evaporation, had strong impacts on the groundwater chemistry in this region. Dissolution of halite and carbonate minerals causes the major reactions controlling water chemistry in this basin. Additionally, the calculation of the saturation index (SI) values suggested that aragonite, calcite, and dolomite are saturated, while halite is not. Based on the analysis of the stable isotope characteristics, atmospheric precipitation, groundwater, and meltwater from the permafrost are the major sources of thermokarst lakes. Moreover, the evaporation-to-inflow ratio (E/I) indicated that all of the lakes continuously expanded and rapidly developed. Overall, groundwater is an crucial source of lake recharge and its hydrochemical characteristics also have a certain impact on lake water quality.

scholarly journals Effects of stratified active layers on high-altitude permafrost warming: a case study on the Qinghai–Tibet Plateau

2016 ◽  
Vol 10 (4) ◽  
pp. 1591-1603 ◽  
Author(s):  
Xicai Pan ◽  
Yanping Li ◽  
Qihao Yu ◽  
Xiaogang Shi ◽  
Daqing Yang ◽  
...  
Keyword(s):  
Thermal State ◽  
Variable Thermal Conductivity ◽  
Tibet Plateau ◽  
Precipitation Pattern ◽  
Thermal Dynamics ◽  
Temperature And Precipitation ◽  
Active Layers ◽  
Permafrost Warming ◽  
Soil Hydraulic ◽  
Qinghai Tibet Plateau

Abstract. Seasonally variable thermal conductivity in active layers is one important factor that controls the thermal state of permafrost. The common assumption is that this conductivity is considerably lower in the thawed than in the frozen state, λt/λf < 1. Using a 9-year dataset from the Qinghai–Tibet Plateau (QTP) in conjunction with the GEOtop model, we demonstrate that the ratio λt/λf may approach or even exceed 1. This can happen in thick (> 1.5 m) active layers with strong seasonal total water content changes in the regions with summer-monsoon-dominated precipitation pattern. The conductivity ratio can be further increased by typical soil architectures that may lead to a dry interlayer. The unique pattern of soil hydraulic and thermal dynamics in the active layer can be one important contributor for the rapid permafrost warming at the study site. These findings suggest that, given the increase in air temperature and precipitation, soil hydraulic properties, particularly soil architecture in those thick active layers must be properly taken into account in permafrost models.

Characteristics of thermokarst lakes and their influence on permafrost in Qinghai–Tibet Plateau

Geomorphology ◽  
2011 ◽  
Vol 132 (3-4) ◽  
pp. 222-233 ◽  
Author(s):  
Fujun Niu ◽  
Zhanju Lin ◽  
Hua Liu ◽  
Jiahao Lu
Keyword(s):  
Tibet Plateau ◽  
Thermokarst Lakes ◽  
Qinghai Tibet Plateau

Geothermal regime in the Qaidam basin, northeast Qinghai–Tibet Plateau

2003 ◽  
Vol 140 (6) ◽  
pp. 707-719 ◽  
Author(s):  
QIU NANSHENG
Keyword(s):  
Heat Flow ◽  
Heat Production ◽  
Thermal State ◽  
Qaidam Basin ◽  
Thermal Structure ◽  
Flow Distribution ◽  
Tibet Plateau ◽  
Upper Crust ◽  
Production Values ◽  
Qinghai Tibet Plateau

The thermal properties of rocks in the upper crust of the Qaidam basin are given based on measurements of 98 thermal conductivities and 50 heat production values. Nineteen new measured heat flow data were obtained from thermal conductivity data and systematic steady-state temperature data. This paper contributes 28 calculated heat flow values for the basin for the first time. Examination of 47 heat flow values, ranging from 31.3 to 70.4 mW/m2 with an average value of 52.6±9.6 mW/m2, gives the heat flow distribution character of the basin: high heat flows over 60 mW/m2 are distributed in the western and central parts of the basin. Lower heat flow values are found in the eastern part and north marginal area of the basin, with values less 40 mW/m2. The Qaidam basin heatflow data show a linear relationship between heatflow and heat production, based on thermal structure analysis. The thermal structure of the lithosphere is characterized as having a ‘hot crust’ but ‘cold mantle’. Heat production in the upper crust is a significant source of heat in the basin and contributes up to 56.8% of the surface heat flow. The heat flow province is of great geophysical significance, and the thermal structure of the area gives clues about the regional geodynamics. Study of the Qaidam basin thermal structure shows that the crust has been highly active, particularly during its most recent geological evolution. This corresponds to Himalayan tectonic movements during latest Eocene to Quaternary times in the region of the Qinghai–Tibet Plateau. Since the Qaidam basin is in the northeastern area of the Qinghai–Tibet Plateau, the heat flow values and the thermal structure of the basin may give some insight into the thermal state of the plateau, and study of thermal regime of the Qaidam basin could in turn provide useful information about the tectonics of the Qinghai–Tibet Plateau.

Sign in / Sign up

Export Citation Format

Share Document