scholarly journals Hydrochemistry of the Lhasa River, Tibetan Plateau: Spatiotemporal Variations of Major Ions Compositions and Controlling Factors Using Multivariate Statistical Approaches

Water ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 3660
Author(s):  
Meizhuang Zhu ◽  
Xingxing Kuang ◽  
Yuqing Feng ◽  
Yinlei Hao ◽  
Qiule He ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
River Water ◽  
Major Ions ◽  
Anthropogenic Activities ◽  
Controlling Factors ◽  
Anthropogenic Activity ◽  
Chemical Compositions ◽  
Spatiotemporal Variations ◽  
Southern Tibetan Plateau ◽  
Lhasa River

Spatiotemporal variations of the hydrochemical major ions compositions and their controlling factors are essential features of a river basin. However, similar studies in the southern Tibetan Plateau are relatively limited. This study focuses on the chemical compositions of the dissolved loads in the Lhasa River (LR) in the southern Tibetan Plateau. Two sampling campaigns were conducted during the rainy and dry seasons across the LR basin to systematically investigate the spatiotemporal variations of water chemistry and sources of the dissolved loads. The results show that the river water possesses slight alkalinity with an average pH of 8.05 ± 0.04. Total dissolved solids (TDS) and oxidation-reduction potential (ORP) range widely from 39.8 mg/L to 582.6 mg/L with an average value of 165.6 ± 7.7 mg/L and from −9.4 mV to 295 mV with a mean value of 153.7 ± 6.9 mV, respectively. The major cations follow the decreasing order of Ca2+, Mg2+, Na+, and K+ while HCO3−, SO42−, Cl−, and NO3− for anions. Ca2+ and Mg2+ account for 87.8% of the total cations, while HCO3− and SO42− accounts for 93.9% of the total anions. All the major ions show higher concentrations in the dry season. NO3−, HCO3−, and Mg2+ show significant spatial variations due to the influence of basin lithology and anthropogenic activity. Multi-variables statistical analysis reveals that the mechanisms controlling the LR hydrochemistry are mainly carbonate weathering followed by silicate weathering. Geothermal springs and anthropogenic activities also play crucial roles in altering river water ions composition in the middle stream and downstream. The relatively high NO3− value (3 ± 0.2 mg/L) suggests water quality will be under the threat of pollution with the increase of anthropogenic activities.

scholarly journals Late Cenozoic Denudation and Topographic Evolution History of the Lhasa River Drainage in Southern Tibetan Plateau: Insights From Inverse Thermal History Modeling

2021 ◽  
Vol 9 ◽  
Author(s):  
Dongxu Cai ◽  
Xianyan Wang ◽  
Guangwei Li ◽  
Wenbin Zhu ◽  
Huayu Lu
Keyword(s):  
Tibetan Plateau ◽  
Surface Erosion ◽  
The Tibetan Plateau ◽  
Monsoon Precipitation ◽  
Late Cenozoic ◽  
River Drainage ◽  
History Of ◽  
Southern Tibetan Plateau ◽  
Lhasa River ◽  
Topographic Evolution

The interaction of surface erosion (e.g., fluvial incision) and tectonic uplift shapes the landform in the Tibetan Plateau. The Lhasa River flows toward the southwest across the central Gangdese Mountains in the southern Tibetan Plateau, characterized by a low-relief and high-elevation landscape. However, the evolution of low-relief topography and the establishment of the Lhasa River remain highly under debate. Here, we collected thermochronological ages reported in the Lhasa River drainage, using a 3D thermokinematic model to invert both late Cenozoic denudation and relief history of the Lhasa River drainage. Our results show that the Lhasa River drainage underwent four-phase denudation history, including two-stage rapid denudation at ∼25–16 Ma (with a rate of ∼0.42 km/Ma) and ∼16–12 Ma (with a rate of ∼0.72 km/Ma). In the latest Oligocene–early Miocene, uplift of the Gangdese Mountains triggered the rapid denudation and the formation of the current main drainage of the Lhasa River. In the middle Miocene, the second stage of the rapid denudation and the high relief were associated with intense incision of the Lhasa River, which is probably due to the enhanced Asian summer monsoon precipitation. This later rapid episode was consistent with the records of regional main drainage systems. After ∼12 Ma, the denudation rate decreases rapidly, and the relief of topography in the central Gangdese region was gradually subdued. This indicates that the fluvial erosion resulting from Asian monsoon precipitation increase significantly impacts on the topographic evolution in the central Gangdese region.

scholarly journals Assessment of Water Quality of a Tropical River with Special Reference to Ions

2020 ◽  
pp. 97-116 ◽  
Author(s):  
R. V. Sheeja ◽  
A. M. Sheela ◽  
S. Jaya ◽  
Sabu Joseph
Keyword(s):  
River Water ◽  
Major Ions ◽  
Anthropogenic Activities ◽  
Anthropogenic Pollution ◽  
Control Measures ◽  
Water Type ◽  
Ion Chemistry ◽  
Major Ion Chemistry ◽  
Tropical River ◽  
Major Ion

The role of ions in a tropical river water (Neyyar, Kerala) was assessed. Rock weathering is the dominating mechanism controlling the major ion chemistry of Neyyar river. The dominance of Cl-HCO3-Na during monsoon indicates that geology plays a major role in controlling water chemistry. The presence of mineral varieties of quartz, feldspars, pyroxene, biotite, etc., in the Pre-Cambrian crystalline namely Khondalite and Charnockites, could be the source of major ions. The major ion chemistry of Neyyar river waters show that Na is the dominant cation with lower proportions of Mg and Ca, with HCO3 and Cl as the dominant anions. It belongs to the HCO3 group with significant amounts of Na and Cacations. The dominance of Cl-HCO3-Ca and Ca-HCO3-Cl during post monsoon and pre monsoon respectively indicates that besides geology, the land drainage and anthropogenic activities also control river water. The change in water type observed during monsoon from Na-Cl-HCO3 to Na-Ca-Cl-HCO3 almost from the middle portion may be attributed to anthropogenic pollution. Hence attention is to be paid to take the control measures to prevent the pollution in this stretch of the river.

Tree-ring reconstruction of Lhasa River streamflow reveals 472 years of hydrologic change on southern Tibetan Plateau

2019 ◽  
Vol 572 ◽  
pp. 169-178 ◽  
Author(s):  
Feng Chen ◽  
Huaming Shang ◽  
Irina P. Panyushkina ◽  
David M. Meko ◽  
Shulong Yu ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Tree Ring ◽  
Hydrologic Change ◽  
Southern Tibetan Plateau ◽  
Tree Ring Reconstruction ◽  
Lhasa River

scholarly journals Hydrogen and Oxygen Isotope Composition and Water Quality Evaluation for Different Water Bodies in the Ebinur Lake Watershed, Northwestern China

Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2067 ◽  
Author(s):  
Zhu ◽  
Zhang ◽  
Zhang ◽  
Kung ◽  
Yushanjiang
Keyword(s):  
Surface Water ◽  
River Water ◽  
Major Ions ◽  
Water Bodies ◽  
Northwestern China ◽  
Anthropogenic Activity ◽  
Total Hardness ◽  
Reservoir Water ◽  
Ebinur Lake ◽  
Volatile Phenol

Wetlands are sensitive indicators of climate change and have a profound impact on the supply of water resources in surrounding areas. In this study, the hydrochemical, isotopic characteristics (δ18O and δ2H) of groundwater and surface water (lake, reservoir, and river) in the Ebinur Lake Watershed, northwestern China, were investigated to reveal the relationships between various water bodies. The results suggest that the groundwater is alkaline and has pH and total dissolved solids (TDS) values less than those of surface water. Ca2+ and SO42− are the major ions in the groundwater and river water, whereas lake water and reservoir water are enriched in Na+ and SO42−. With the decrease in elevation, both groundwater and river water are affected by carbonate dissolution at high elevation and by evaporitic rock dissolution at low elevation; thus, the water surrounding Ebinur Lake is subjected to runoff affected by intense evaporation–dissolution of evaporitic rocks. The stable isotope compositions suggested that the upstream part of the river is recharged by glacial meltwater from high mountains, whereas the middle–downstream parts of the river are recharged by low-elevation precipitation. Shallow groundwater and reservoir water are mainly recharged by river water and are more enriched in the downstream part of river. Water samples were also classified according to different indices, such as chemical oxygen demand (COD), NH3-N, volatile phenol, sulfate, Zn, Co, Cu, total hardness, and Cr6+, and results showed that most groundwater is suitable for drinking and irrigation purposes. Except for Cr6+, the metal concentrations are within permissible limits. However, both groundwater and reservoir water are affected to some extent by nearby rivers from anthropogenic activity.

scholarly journals Changes in ionic concentrations and δ18O in the snowpack of Zhadang glacier, Nyainqentanglha mountain, southern Tibetan Plateau

2008 ◽  
Vol 49 ◽  
pp. 127-134 ◽  
Author(s):  
Kang Shichang ◽  
Huang Jie ◽  
Xu Yanwei
Keyword(s):  
Tibetan Plateau ◽  
Air Temperature ◽  
Major Ions ◽  
Meteorological Data ◽  
Sampling Site ◽  
High Elevation ◽  
Depositional Processes ◽  
Southern Tibetan Plateau ◽  
Climate Signals ◽  
High Concentrations

AbstractTo investigate the effects of depositional and post-depositional processes on chemical records in the snowpack, seven monthly snow pits were sampled at the same site on the pass of Zhadang (ZD) glacier (30˚28.079' N, 90˚39.032' E; 5800ma.s.l.), Nyainqentanglha mountain, southern Tibetan Plateau, between April and October 2006. Meteorological data from an automatic weather station at the sampling site showed that the annual mean air temperature was –5.6˚C on the pass and that monthly air temperature was above 0˚C from June to August, indicating that snowmelt could occur in this high-elevation region during the summer. An analysis of δ18O and major-ion variability in snow pits suggests that glaciochemical recordswere influenced by both meltwater percolation in mid-summer (July and August) and seasonal deposition. Less negative δ18O values and high concentrations of major ions occurred during the spring. The trends of δ18O variations in the ZD snow pits were consistent with those in precipitation sampled at the nearby Nam Co station for all months except for July and August, suggesting that climate signals are well preserved in the snow-pit δ18O records during the non-summer months. However, these climate signals were destroyed by strong percolation of meltwater during mid-summer.

Major Ionic Composition of Precipitation in the Shigatse Region, Southern Tibetan Plateau

2011 ◽  
Vol 347-353 ◽  
pp. 1005-1011 ◽  
Author(s):  
Yong Jie Yang ◽  
Jun Qing Liu ◽  
Yi An Di ◽  
Jun Yang ◽  
Tian Xue Wen ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Major Ions ◽  
Ionic Composition ◽  
Combustion Products ◽  
The South ◽  
Air Masses ◽  
Average Value ◽  
Major Cations ◽  
Southern Tibetan Plateau ◽  
Precipitation Events

Abstract. In order to investigate the chemical characteristics of precipitation on Tibetan Plateau, a total of 34 precipitation samples have been collected from individual precipitation events at the Shigatse Meteorological Station located in the south Tibetan Plateau in 2008. All samples were analyzed for major cations (NH4+, Na+, K+, Ca2+ and Mg2+) and anions (Cl−, NO3− and SO42−), conductivity and pH. The result showed that precipitation pH values ranged from 6.79 to 9.21 with an average value of 7.86. HCO3− and Ca2+ were the major ions detected in the samples, occupied 39% and 35% of the total ion mass, 80% of the total anion mass and 69% of the total cations mass, respectively. Factor analysis indicated that regional crustal dust, lake salt and local combustion products of residents were the main sources of the ionic compositions of precipitation of Shigatse region. Trajectory cluster analysis indicated that 97.1% of the air masses reaching Shigatse originated from the south, which passed through some pollution regions, as southeast Indian, Bangladesh.

scholarly journals Water Quality and Hydrogeochemical Characteristics of Some Karst Water Sources in Apuseni Mountains, Romania

Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 857
Author(s):  
Maria-Alexandra Hoaghia ◽  
Ana Moldovan ◽  
Eniko Kovacs ◽  
Ionut Cornel Mirea ◽  
Marius Kenesz ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Chemistry ◽  
Major Ions ◽  
Anthropogenic Activities ◽  
Water Sources ◽  
Main Process ◽  
Karst Water ◽  
Rock Interaction ◽  
Apuseni Mountains ◽  
Karst Waters

Human activities and natural factors determine the hydrogeochemical characteristics of karst groundwaters and their use as drinking water. This study assesses the hydrogeochemical characteristics of 14 karst water sources in the Apuseni Mountains (NW Romania) and their potential use as drinking water sources. As shown by the Durov and by the Piper diagrams, the chemical composition of the waters is typical of karst waters as it is dominated by HCO3− and Ca2+, having a circumneutral to alkaline pH and total dissolved solids ranging between 131 and 1092 mg L−1. The relation between the major ions revealed that dissolution is the main process contributing to the water chemistry. Limestone and dolostone are the main Ca and Mg sources, while halite is the main Na and Cl source. The Gibbs diagram confirmed the rock dominance of the water chemistry. The groundwater quality index (GWQI) showed that the waters are of excellent quality, except for two waters that displayed medium and good quality status. The quality of the studied karst waters is influenced by the geological characteristics, mainly by the water–rock interaction and, to a more limited extent, by anthropogenic activities. The investigated karst waters could be exploited as drinking water resources in the study area. The results of the present study highlight the importance of karst waters in the context of good-quality water shortage but also the vulnerability of this resource to anthropogenic influences.

scholarly journals Ground-Based MAX-DOAS Observations of Tropospheric NO2 and HCHO During COVID-19 Lockdown and Spring Festival Over Shanghai, China

2021 ◽  
Vol 13 (3) ◽  
pp. 488
Author(s):  
Aimon Tanvir ◽  
Zeeshan Javed ◽  
Zhu Jian ◽  
Sanbao Zhang ◽  
Muhammad Bilal ◽  
...  
Keyword(s):  
Air Quality ◽  
Anthropogenic Activities ◽  
Anthropogenic Activity ◽  
Hysplit Model ◽  
Vertical Column ◽  
Weekly Cycle ◽  
Spring Festival ◽  
Level 1 ◽  
Reduced Mobility ◽  
The Impact

Reduced mobility and less anthropogenic activity under special case circumstances over various parts of the world have pronounced effects on air quality. The objective of this study is to investigate the impact of reduced anthropogenic activity on air quality in the mega city of Shanghai, China. Observations from the highly sophisticated multi-axis differential optical absorption spectroscope (MAX-DOAS) instrument were used for nitrogen dioxide (NO2) and formaldehyde (HCHO) column densities. In situ measurements for NO2, ozone (O3), particulate matter (PM2.5) and the air quality index (AQI) were also used. The concentration of trace gases in the atmosphere reduces significantly during annual Spring Festival holidays, whereby mobility is reduced and anthropogenic activities come to a halt. The COVID-19 lockdown during 2020 resulted in a considerable drop in vertical column densities (VCDs) of HCHO and NO2 during lockdown Level-1, which refers to strict lockdown, i.e., strict measures taken to reduce mobility (43% for NO2; 24% for HCHO), and lockdown Level-2, which refers to relaxed lockdown, i.e., when the mobility restrictions were relaxed somehow (20% for NO2; 22% for HCHO), compared with pre-lockdown days, as measured by the MAX-DOAS instrument. However, for 2019, a reduction in VCDs was found only during Level-1 (24% for NO2; 6.62% for HCHO), when the Spring Festival happened. The weekly cycle for NO2 and HCHO depicts no significant effect of weekends on the lockdown. After the start of the Spring Festival, the VCDs of NO2 and HCHO showed a decline for 2019 as well as 2020. Backward trajectories calculated using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model indicated more air masses coming from the sea after the Spring Festival for 2019 and 2020, implying that a low pollutant load was carried by them. No impact of anthropogenic activity was found on O3 concentration. The results indicate that the ratio of HCHO to NO2 (RFN) fell in the volatile organic compound (VOC)-limited regime.

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