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Paudel Adhikari N, Adhikari S, Aryal D. Hydrochemical and isotopic characteristics on the southern and northern slopes of the Himalayas: spatio-temporal controls and source apportionment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 949:175147. [PMID: 39084375 DOI: 10.1016/j.scitotenv.2024.175147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 06/30/2024] [Accepted: 07/28/2024] [Indexed: 08/02/2024]
Abstract
Water-soluble ions, inorganic nitrogen, and stable isotopes in precipitation were assessed from the southern (Koshi Tappu and Khandbari) and northern slopes (Lhasa and SET) of the Himalayas to understand the sources, chemistry of regional precipitation, and climatic processes. Water soluble ions showed distinct seasonal variation, with higher concentrations in the non-monsoon. The concentration of ionic species was highest in Koshi Tappu, followed by Lhasa, SET, and Khandbari. The sources were from the terrigenous (Ca2+, HCO3-), marine (Na+ and Cl-), anthropogenic (SO42-, NO3-, and NH4+), terrigenous and marine (Mg2+), and biomass-burning (K+). The southern slope, relative to the northern, was more prone to anthropogenic emissions with higher deposition. Among all sites, inorganic nitrogen deposition at Koshi Tappu was higher than the threshold value (10 kg ha-1 y-1). The isotopic composition during the study period was higher in non-monsoon, started declining from June, and depleted in July and August compared to other months, i.e., the monsoon mature phase, along the south-to-north transect. The diminished value of stable isotopes in precipitation with increasing altitude underlines the evidence of the orographic effect in isotopic composition. Our study delineated that the higher/lower d-excess value increased with altitude on the southern/northern slope of the Himalayas. The backward trajectory analysis and the National Centers for Environmental Prediction's Final (NCEP FNL) datasets identified that most of the trajectories arrived from warm and humid low-latitude regions during monsoon and westerlies in non-monsoon. Thus, the chemical characteristics and stable isotopic composition of precipitation differed on the southern and northern slopes of the Himalayas by orographic effect and various sources. This study provides new insights into the atmospheric environment and climatic control of stable isotopes in the Himalayan Tibetan Plateau and facilitates monitoring of transboundary air pollution.
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Affiliation(s)
- Namita Paudel Adhikari
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Center for the Pan-third Pole Environment, Lanzhou University, Lanzhou 730000, China
| | - Subash Adhikari
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Policy and Planning Commission, Gandaki Province, Pokhara 33700, Nepal.
| | - Deepak Aryal
- Central Department of Hydrology and Meteorology, Tribhuvan University, Kirtipur, Kathmandu 44613, Nepal
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Rawat B, Sharma CM, Tripathee L, Wan X, Cong Z, Paudyal R, Pandey A, Kandel K, Kang S, Zhang Q. Concentration, seasonality, and sources of trace elements in atmospheric aerosols from Godavari in the southern Himalayas. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 344:123359. [PMID: 38228261 DOI: 10.1016/j.envpol.2024.123359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 12/14/2023] [Accepted: 01/13/2024] [Indexed: 01/18/2024]
Abstract
Atmospheric pollution has detrimental effects on human health and ecosystems. The southern region of the Himalayas, undergoing rapid urbanization and intense human activities, faces poor air quality marked by high aerosol loadings. In this study, we conducted a two-year PM10 sampling in the suburban area (Godavari) of Kathmandu, a representative metropolis situated in the southern part of the central Himalayas. The trace elements were measured to depict aerosol-bound element loadings, seasonality, and potential sources. The mean concentrations of trace elements varied considerably, ranging from 0.27 ± 0.19 ng m-3 for Tl to 1252.78 ng m-3 for Zn. The average concentration of Co and Ni was 1.2 and 22.4 times higher, respectively, than those in Lhasa city in Tibet in the northern Himalayas. The concentration of Pb was 38 times lower than that in Lahore, Pakistan, and 9 times lower than urban sites in India. For the seasonality, the trace element concentrations displayed remarkable variation, with higher concentrations during the non-monsoon seasons and lower concentrations during the monsoon season. This trend was primarily influenced by anthropogenic activities such as low-grade fuel combustion in vehicles, coal combustion in brick kilns, and biomass burning, along with seasonal rainfall that induced aerosol washout. The enrichment factors (EFs) analysis revealed that Cd, Zn, Sb, Ni, Cu, Cr, and Pb had higher EFs, indicating their significant contributions from anthropogenic sources. In contrast, elements like Tl, Co, V, Cs, U, Ba, Th, and Sr, characterized by lower EFs, were mainly associated with natural sources. The Pb isotopic ratio profiles exhibited the Pb in PM10 are derived major contribution from legacy lead. Biomass burning contributed to the Pb source in winter. These findings provide policymakers with valuable insights to develop guidelines and strategies aimed at improving air quality and mitigating the impact of aerosol pollution on human health in the Himalayan region.
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Affiliation(s)
- Bakhat Rawat
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Centre for Atmospheric Chemistry, University of Wollongong (UOW), NSW, 2522, Australia
| | - Chhatra Mani Sharma
- Central Department of Environmental Science, Tribhuvan University, Kritipur, Kathmandu, Nepal
| | - Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Xin Wan
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Zhiyuan Cong
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; School of Ecology and Environment, Tibet University, Lhasa, 850000, China
| | - Rukumesh Paudyal
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Aastha Pandey
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kshitiz Kandel
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shichang Kang
- University of Chinese Academy of Sciences, Beijing, 100049, China; State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Qianggong Zhang
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
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Bhatta R, Gurung S, Joshi R, Tuladhar S, Regmi D, Kafle BK, Dahal BM, Raut N, Kafle KR, Kayastha R, Prasad A, Tripathee L, Paudyal R, Guo J, Kang S, Sharma CM. Spatio-temporal hydrochemistry of two selected Ramsar sites (Rara and Ghodaghodi) of west Nepal. Heliyon 2022; 8:e11243. [PMCID: PMC9636469 DOI: 10.1016/j.heliyon.2022.e11243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 08/08/2022] [Accepted: 10/20/2022] [Indexed: 11/07/2022] Open
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Vithanage M, Bandara PC, Novo LAB, Kumar A, Ambade B, Naveendrakumar G, Ranagalage M, Magana-Arachchi DN. Deposition of trace metals associated with atmospheric particulate matter: Environmental fate and health risk assessment. CHEMOSPHERE 2022; 303:135051. [PMID: 35671821 DOI: 10.1016/j.chemosphere.2022.135051] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/29/2022] [Accepted: 05/19/2022] [Indexed: 06/15/2023]
Abstract
Anthropogenic and natural sources influence trace metals (TMs) bound to different sized particulate matter (PM) in dry and wet atmospheric deposition, which can create ecosystem and human health issues in the long run. Limited reviews are available summarizing worldwide concentrations in TMs in atmospheric PMs, their sources and pathways. Simultaneously, quantitative assessment of the potential human and ecosystem health risks imposed by the atmospheric particulate matter has not been adequately reviewed. Addressing this gap, here we review, the concentration of TMs in dry deposition mainly varies with the responsible sources, whereas, in wet deposition, it depends on the solubility of TMs. Other than deposition on impervious surfaces, the TMs incorporated PM can be deposited on biological agents. Health risk assessments show that ingestion and dermal contact pathways are more likely to cause health issues, however, the probability of occurring ingestion and dermal contact pathways is limited. Attention must be paid to the contribution from non-exhaust and exhaust vehicular emissions for TMs in atmospheric deposition, understanding their impact on stormwater management and urban agriculture. Behaviors of TMs in the atmosphere depends on many complex factors including origin, wind patterns, and weather conditions. Therefore, future research needs to be carried to model and predict the fate and transfer of TMs once they are generated through natural and anthropogenic sources. We believe that such research would allow establishing pollution control policies and measures in urban environments which will be critical to reduce the levels of TMs associated with atmospheric deposition in the environment.
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Affiliation(s)
- Meththika Vithanage
- Ecosphere Resilience Research Centre, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, 10250, Sri Lanka; Molecular Biology and Human Diseases Project, National Institute of Fundamental Studies, Kandy, Sri Lanka.
| | - Pasan Chinthana Bandara
- Department of Biosystems Technology, Faculty of Technology, University of Sri Jayewardenepura, Sri Lanka
| | - Luís A B Novo
- Scotland's Rural College (SRUC), West Mains Road, Edinburgh, EH9 3JG, UK
| | - Amit Kumar
- Department of Chemistry, National Institute of Technology Jamshedpur, Jharkhand, 831014, India
| | - Balram Ambade
- Department of Chemistry, National Institute of Technology Jamshedpur, Jharkhand, 831014, India
| | - G Naveendrakumar
- Department of Bio-science, University of Vavuniya, Pampaimadu, Vavuniya, Sri Lanka
| | - Manjula Ranagalage
- Department of Environmental Management, Faculty of Social Sciences and Humanities, Rajarata University of Sri Lanka, Mihintale, 50300, Sri Lanka
| | - Dhammika N Magana-Arachchi
- Molecular Biology and Human Diseases Project, National Institute of Fundamental Studies, Kandy, Sri Lanka
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Kumar R, Kumar R, Singh A, Arif M, Kumar P, Kumari A. Chemometric approach to evaluate the chemical behavior of rainwater at high altitude in Shaune Garang catchment, Western Himalaya. Sci Rep 2022; 12:12774. [PMID: 35896609 PMCID: PMC9329433 DOI: 10.1038/s41598-022-15422-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 06/23/2022] [Indexed: 11/22/2022] Open
Abstract
The present research has been performed to analyze the chemical behavior of rainwater of the Shaune Garang catchment (32.19° N, 78.20° E) in the Baspa basin, located at a high elevation (4221 m above mean sea level) in the Himachal Himalaya, India. During the study period, sixteen rainwater samples were collected from the Shaune Garang catchment at five different sites. The volume-weighted mean (VWM) pH value of rainwater ranged between 4.59 and 6.73, with an average value of 5.47 ± 0.69, indicating the alkaline nature of rainfall. The total ionic strength in the rainwater ranged from 113.4 to 263.3 µeq/l with an average value of 169.1 ± 40.4 µeq/l. The major dominant cations were Ca2+ (43.10%) and Na+ (31.97%) and anions were Cl− (37.68%), SO42− (28.71%) and NO3− (23.85%) in rainwater. The ionic ratios were calculated among all the ions. The fraction of (NO3− +Cl−) with SO42− was measured as 2.3, which specifies sour faces of rainwater due to HNO3, H2SO4, and HCl. A multivariate statistical assessment of rainwater chemistry through Principal Component Analysis (PCA) shows the significance of four factors controlling 78.37% of the total variance, including four-component (PC1 explained 27.89%, PC2 explained 24.98%, PC3 explained 14.64%, PC4 explained 10.85%). However, the individual contribution of Factor 1(PC1) explains 27.89% of the total variance (78.37%) and displays a strong optimistic loading for Ca2+ and Cl−. Further, high loading of Ca2+ and NO3− and moderate loading of SO42− signify the contribution of burning fossil fuel and soil dust. Anthropogenic and natural pollutants influence the composition of rainwater in the pristine Himalayas due to local and long-distance transportation. The study area receives precipitation from the West and North-West, transporting dust and fossil fuel emissions from the Thar Desert and Northwestern countries.
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Affiliation(s)
- Ramesh Kumar
- Department of Environmental Science, School of Earth Sciences, Central University of Rajasthan, Bandar Sindri, Ajmer, Rajasthan, India
| | - Rajesh Kumar
- Department of Environmental Science, School of Earth Sciences, Central University of Rajasthan, Bandar Sindri, Ajmer, Rajasthan, India.
| | - Atar Singh
- Department of Environmental Science, School of Earth Sciences, Central University of Rajasthan, Bandar Sindri, Ajmer, Rajasthan, India
| | - Mohammad Arif
- National Institute of Urban Affairs, Ministry of Housing and Urban Affairs, Delhi, India
| | - Pankaj Kumar
- Integrated Regional Office, Ministry of Environment, Forest and Climate Change (MoEFCC), Government of India, Saifabad, Hyderabad, Telangana, India
| | - Anupma Kumari
- Environmental Biology Laboratory, Department of Zoology, Patna University, Patna, Bihar, India
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Distribution Pattern of Woody Plants in a Mountain Forest Ecosystem Influenced by Topography and Monsoons. FORESTS 2022. [DOI: 10.3390/f13060957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Many areas are affected by the monsoon because of different sea and land positions. At the same time, the blocking effect of a mountain range forms different habitats on both sides of the mountain range. However, the distribution mechanism of woody plants is unclear in mountain forest ecosystems influenced by topography and monsoons. In this study, 10 plots, each with an area of 1 hm2 (100 m × 100 m), were randomly established on the south and north aspects of a mountain forest. We examined community structure differences and distribution preferences of woody plants on both sides of the mountain. Our findings were as follows: (1) The characteristics of woody plant assemblages differed among various aspects. (2) Network analysis showed that specialization index was 0.186 and modularity index was 0.235, and the torus translation test showed that a total of 45 species were detected to be associated with at least one of the habitats (45/106, 42.45%). (3) The community stability of the south aspect was higher than that of the north aspect. Our findings suggest that the distribution of woody plants among different aspects was specialized and not random in alpine forest ecosystems. This study contributes to a clear understanding of the distribution mechanism of woody plants in mountain forest ecosystems influenced by topography and monsoons.
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Bhattarai H, Tripathee L, Kang S, Chen P, Sharma CM, Ram K, Guo J, Rupakheti M. Nitrogenous and carbonaceous aerosols in PM 2.5 and TSP during pre-monsoon: Characteristics and sources in the highly polluted mountain valley. J Environ Sci (China) 2022; 115:10-24. [PMID: 34969440 DOI: 10.1016/j.jes.2021.06.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 06/09/2021] [Accepted: 06/20/2021] [Indexed: 06/14/2023]
Abstract
This study reports for the first time a comprehensive analysis of nitrogenous and carbonaceous aerosols in simultaneously collected PM2.5 and TSP during pre-monsoon (March-May 2018) from a highly polluted urban Kathmandu Valley (KV) of the Himalayan foothills. The mean mass concentration of PM2.5 (129.8 µg/m3) was only ~25% of TSP mass (558.7 µg/ m3) indicating the dominance of coarser mode aerosols. However, the mean concentration as well as fractional contributions of water-soluble total nitrogen (WSTN) and carbonaceous species reveal their predominance in find-mode aerosols. The mean mass concentration of WSTN was 17.43±4.70 µg/m3 (14%) in PM2.5 and 24.64±8.07 µg/m3 (5%) in TSP. Moreover, the fractional contribution of total carbonaceous aerosols (TCA) is much higher in PM2.5 (~34%) than that in TSP (~20%). The relatively low OC/EC ratio in PM2.5 (3.03 ± 1.47) and TSP (4.64 ± 1.73) suggests fossil fuel combustion as the major sources of carbonaceous aerosols with contributions from secondary organic aerosols. Five-day air mass back trajectories simulated with the HYSPLIT model, together with MODIS fire counts indicate the influence of local emissions as well as transported pollutants from the Indo-Gangetic Plain region to the south of the Himalayan foothills. Principal component analysis (PCA) also suggests a mixed contribution from other local anthropogenic, biomass burning, and crustal sources. Our results highlight that it is necessary to control local emissions as well as regional transport while designing mitigation measures to reduce the KV's air pollution.
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Affiliation(s)
- Hemraj Bhattarai
- Earth System Science Programme and Graduate Division of Earth and Atmospheric Sciences, The Chinese University of Hong Kong, Hong Kong, China; Himalayan Environment Research Institute (HERI), Kathmandu 44602, Nepal
| | - Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Himalayan Environment Research Institute (HERI), Kathmandu 44602, Nepal.
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, CAS, Beijing 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100085, China
| | - Pengfei Chen
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China
| | - Chhatra Mani Sharma
- Himalayan Environment Research Institute (HERI), Kathmandu 44602, Nepal; Central Department of Environmental Sciences, Tribhuvan University, Kathmandu 44613, Nepal
| | - Kirpa Ram
- Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi 221005, India
| | - Junming Guo
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China
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Ahmed MS, Bhuyan P, Sarkar S, Hoque RR. Seven-year study of monsoonal rainwater chemistry over the mid-Brahmaputra plain, India: assessment of trends and source regions of soluble ions. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:25276-25295. [PMID: 34839462 DOI: 10.1007/s11356-021-17385-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
This work is a 7-year study of monsoonal rainwater chemistry (n = 302), over mid-Brahmaputra plain during 2012 to 2018. The samples were analyzed for major chemical parameters viz. pH, electrical conductivity (EC), and ions (SO42-, NO3-, Br-, Cl-, F-, Mg2+, Ca2+, K+, NH4+, Na+, and Li+) to assess the chemistry. The mean pH of rainwater varied among the years, which was maximum in 2018 (6.18 ± 0.72) and minimum in the year 2014 (5.39 ± 0.54), and the variations were significant at p < 0.0001. Ridgeline plots were drawn to visualize interannual variations, which revealed that Ca2+ was the dominant cation in the early years, whereas NH4+ prevailed in the latter years. Mann-Kendall analysis and Sen's slope statistical tests were employed, and it was found that all the ions showed positive S values indicating increasing trends. Enrichment factors (EF) of K+, SO42-, and NO3- were found to be high with respect to both soil and seawater suggesting the influence of emissions from fossil fuel and biomass burning in the chemistry of rainwater. Principal component analysis (PCA) was applied to identify the sources of rain constituents, and five factors were obtained explaining crustal dust, biomass burning, fossil fuel combustion, agricultural emissions, and coal burning as possible sources. Airmass back trajectory clusters and Potential Source Contribution Function (PSCF) were computed by application of HYbrid Single-Particle Lagrangian Integrated Trajectory model to appreciate the terrestrial influence on the chemistry. The results indicated inputs from both local and regional dust and anthropogenic constituents that influenced the monsoonal rainwater chemistry over Brahmaputra Valley.
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Affiliation(s)
- Md Sahbaz Ahmed
- Department of Environmental Science, Tezpur University, Tezpur, India
| | - Pranamika Bhuyan
- Department of Environmental Science, Tezpur University, Tezpur, India
- Department of Environmental Studies, Assam Women's University, Jorhat, India
| | - Sayantan Sarkar
- School of Engineering, IIT Mandi, Suran, Himachal Pradesh, India
| | - Raza R Hoque
- Department of Environmental Science, Tezpur University, Tezpur, India.
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Characterization and Source Discovery of Wintertime Fog on Coastal Island, Bangladesh. ATMOSPHERE 2022. [DOI: 10.3390/atmos13030497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
An extensive chemical investigation of fog water’s chemical composition, as well as source characterization, were carried out during the winter season (December to February) at an outflow location (Bhola, Bangladesh) of the Indo-Gangetic Plain (IGP). Characterization of the source involved correlational analysis, enrichment factor analysis, estimation of percentage sources, and air mass trajectory analysis. The average pH of fog water in Bhola was found to be 7.03 ± 0.02, demonstrating that acid-neutralizing components were successful in neutralizing acidifying species. The concentrations of the water-soluble ions were determined, and they were in the following order: Ca2+ > NO3− > Cl− > Na+ > SO42− > NH4+ > Mg2+ > K+ > F− > HCO3−. Of the six trace elements (Fe, Zn, Mn, Cu, Ni, Cr, Pb) that were analyzed, Zn ions were found in the highest concentration, followed by Mn ions. Neutralization factor analysis showed that the key neutralization components of fog-water were Ca2+ and NH4+. Enrichment factor (EF) calculation revealed the anthropogenic origin of NO3−, SO42−, Zn, Mn, and Cu. The percentage source contributions of NO3− (99.74%), SO42− (84.02%), and Cl− (8.30%) further support the anthropogenic origin. Backward air mass trajectory analysis was performed using the NOAA-HYSPLIT model. Long-range transport of contaminants over the IGP area was found to have a profound impact on the chemical composition of fog on the Bhola coast. This research has provided novel findings for the chemical characterization of fog water and the detection of its source at IGP outflow, and highlighted the anthropogenic contributions to local air pollution, as well as the transboundary influence on local air quality.
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Clifford HM, Potocki M, Koch I, Sherpa T, Handley M, Korotkikh E, Introne D, Kaspari S, Miner K, Matthews T, Perry B, Guy H, Gajurel A, Singh PK, Elvin S, Elmore AC, Tait A, Mayewski PA. A case study using 2019 pre-monsoon snow and stream chemistry in the Khumbu region, Nepal. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 789:148006. [PMID: 34082206 DOI: 10.1016/j.scitotenv.2021.148006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 05/11/2021] [Accepted: 05/20/2021] [Indexed: 06/12/2023]
Abstract
This case study provides a framework for future monitoring and evidence for human source pollution in the Khumbu region, Nepal. We analyzed the chemical composition (major ions, major/trace elements, black carbon, and stable water isotopes) of pre-monsoon stream water (4300-5250 m) and snow (5200-6665 m) samples collected from Mt. Everest, Mt. Lobuche, and the Imja Valley during the 2019 pre-monsoon season, in addition to a shallow ice core recovered from the Khumbu Glacier (5300 m). In agreement with previous work, pre-monsoon aerosol deposition is dominated by dust originating from western sources and less frequently by transport from southerly air mass sources as demonstrated by evidence of one of the strongest recorded pre-monsoon events emanating from the Bay of Bengal, Cyclone Fani. Elevated concentrations of human-sourced metals (e.g., Pb, Bi, As) are found in surface snow and stream chemistry collected in the Khumbu region. As the most comprehensive case study of environmental chemistry in the Khumbu region, this research offers sufficient evidence for increased monitoring in this watershed and surrounding areas.
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Affiliation(s)
- Heather M Clifford
- Climate Change Institute, University of Maine, ME, USA; School of Earth and Climate Sciences, University of Maine, ME, USA.
| | - Mariusz Potocki
- Climate Change Institute, University of Maine, ME, USA; School of Earth and Climate Sciences, University of Maine, ME, USA
| | - Inka Koch
- International Centre for Integrated Mountain Development, Lalitpur, Nepal; Department of Geosciences, University of Tübingen, Tübingen, Germany
| | - Tenzing Sherpa
- International Centre for Integrated Mountain Development, Lalitpur, Nepal
| | - Mike Handley
- Climate Change Institute, University of Maine, ME, USA
| | | | | | - Susan Kaspari
- Department of Geological Sciences, Central Washington University, WA, USA
| | | | - Tom Matthews
- Department of Geography and Environment, Loughborough University, Loughborough, UK
| | - Baker Perry
- Department of Geography and Planning, Appalachian State University, NC, USA
| | - Heather Guy
- School of Earth and Environment, University of Leeds, UK
| | - Ananta Gajurel
- Central Department of Geology, Tribhuvan University, Kathmandu, Nepal
| | - Praveen Kumar Singh
- International Centre for Integrated Mountain Development, Lalitpur, Nepal; CoEDMM, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India
| | - Sandra Elvin
- National Geographic Society, 1145 17th St. NW, Washington, DC, USA
| | - Aurora C Elmore
- National Geographic Society, 1145 17th St. NW, Washington, DC, USA
| | - Alex Tait
- National Geographic Society, 1145 17th St. NW, Washington, DC, USA
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Pant RR, Qaiser FUR, Wang G, Adhikari S, Bishwakarma K, Baral U, Rimal B, Bhatta YR, Rijal K. Hydrochemical appraisal and solute acquisitions in Seti River Basin, Central Himalaya, Nepal. ENVIRONMENTAL MONITORING AND ASSESSMENT 2021; 193:656. [PMID: 34532822 DOI: 10.1007/s10661-021-09437-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 08/30/2021] [Indexed: 06/13/2023]
Abstract
The chemical characterization and assessment of the water quality in the headwater areas of the Himalaya are necessary for securing the water in the future. This study aims to assess the hydrochemistry and water quality concerning drinking and irrigational uses in the Seti River Basin (SRB), Nepal. A total of 45 water samples were collected in 2016 from the SRB during pre-monsoon, monsoon, and post-monsoon seasons, and pH, EC, TDS, and DO were measured on-site, whereas Ca2+, Mg2+, K+, Na+, Cl-, SO42-, NO3-, and dissolved Si were analyzed in the laboratory. The results revealed mildly alkaline pH (8.40 ± 0.43) with the pattern of average ionic dominancy: Ca2+ > Mg2+ > Na+ > K+ and HCO3- > SO42- > Cl- > NO3- for cations and anions, respectively. Gibbs diagram implied that the lithogenic weathering mainly controlled the solute acquisition process, which was further confirmed by the Piper diagram, exhibiting Ca-HCO3 as the governing hydrochemical facies (91%). The average molar ratios were 0.88, 8.33, and 6.86 of (Ca2+ + Mg2+)/TZ+, (Ca2+ + Mg2+)/(Na+ + K+), and HCO3-/(Na+ + K+), respectively, which specified that the carbonate weathering largely controlled the solute acquisition processes with a minor contribution of silicates. The mass budget calculation also confirmed the dominance of carbonate weathering (72.0%, 78.9%, and 62.0% in Pre-Monsoon, Monsoon, and Post-Monsoon, respectively) and the high monsoon rainfall's dilution effect to anthropogenic input of cations. Principal component analysis and correlation matrix exhibited that the major sources of ions in the basin were geogenic with minor anthropic signatures. Furthermore, water quality in connection to drinking and irrigation uses revealed that the basin has mostly retained its natural water quality. This investigation suggests that regular monitoring and assessment are essential for maintaining the water quality and ecological integrity in the Himalayan river basins.
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Affiliation(s)
- Ramesh Raj Pant
- Central Department of Environmental Science, Tribhuvan University, Kathmandu, Nepal
| | - Faizan Ur Rehman Qaiser
- Department of Earth Sciences, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, Pakistan
| | - Guanxing Wang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Subash Adhikari
- Provincial Policy and Planning Commission, Gandaki Province, Pokhara, Nepal
| | - Kiran Bishwakarma
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Upendra Baral
- Kathmandu Center for Research and Education, CAS-TU, Kathmandu, Nepal
- Key Laboratory of Continental Collision and Plateau Uplift, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Bhagawat Rimal
- College of Applied Sciences (CAS)-Nepal, Tribhuvan University, Kathmandu, Nepal
| | - Youb Raj Bhatta
- Central Department of Environmental Science, Tribhuvan University, Kathmandu, Nepal
| | - Kedar Rijal
- Central Department of Environmental Science, Tribhuvan University, Kathmandu, Nepal
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Bhattarai H, Tripathee L, Kang S, Sharma CM, Chen P, Guo J, Ghimire PS. Concentration, sources and wet deposition of dissolved nitrogen and organic carbon in the Northern Indo-Gangetic Plain during monsoon. J Environ Sci (China) 2021; 102:37-52. [PMID: 33637262 DOI: 10.1016/j.jes.2020.09.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 08/21/2020] [Accepted: 09/04/2020] [Indexed: 06/12/2023]
Abstract
Precipitation represents an important phenomenon for carbon and nitrogen deposition. Here, the concentrations and fluxes of dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) with their potential sources were analyzed in wet precipitation during summer monsoon from the Northern Indo-Gangetic Plain (IGP), important but neglected area. The volume-weighted mean (VWM) concentration of DOC and TDN were 687.04 and 1210.23 µg/L, respectively. Similarly, the VWM concentration of major ions were in a sequence of NH4+ > Ca2+ > SO42- > Na+ > K+ > NO3- > Cl- > Mg2+ > F- > NO2-, suggesting NH4+ and Ca2+ from agricultural activities and crustal dust played a vital role in precipitation chemistry. Moreover, the wet deposition flux of DOC and TDN were 9.95 and 17.06 kg/(ha⋅year), respectively. The wet deposition flux of inorganic nitrogen species such as NH4+-N and NO3--N were 14.31 and 0.47 kg/(ha⋅year), respectively, demonstrating the strong influence of emission sources and precipitation volume. Source attribution from different analysis suggested the influence of biomass burning on DOC and anthropogenic activities (agriculture, animal husbandry) on nitrogenous species. The air-mass back trajectory analysis indicated the influence of air masses originating from the Bay of Bengal, which possibly carried marine and anthropogenic pollutants along with the biomass burning emissions to the sampling site. This study bridges the data gap in the less studied part of the northern IGP region and provides new information for policy makers to deal with pollution control.
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Affiliation(s)
- Hemraj Bhattarai
- Earth System Science Programme and Graduate Division of Earth and Atmospheric Sciences, The Chinese University of Hong Kong, Hong Kong, China; Himalayan Environment Research Institute (HERI), Kathmandu, Nepal; Kathmandu Center for Research and Education (KCRE), Kathmandu, Nepal
| | - Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Himalayan Environment Research Institute (HERI), Kathmandu, Nepal.
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, CAS, Beijing 100101, China; Chinese Academy of Sciences (CAS) Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100085, China
| | | | - Pengfei Chen
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China
| | - Junming Guo
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China
| | - Prakriti Sharma Ghimire
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Central Department of Environmental Science, Tribhuvan University, Kathmandu, Nepal
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Paudyal R, Kang S, Tripathee L, Guo J, Sharma CM, Huang J, Niu H, Sun S, Pu T. Concentration, spatiotemporal distribution, and sources of mercury in Mt. Yulong, a remote site in southeastern Tibetan Plateau. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:16457-16469. [PMID: 30980371 DOI: 10.1007/s11356-019-05005-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 03/26/2019] [Indexed: 06/09/2023]
Abstract
The unique geographic location of Mt. Yulong in the Tibetan Plateau (TP) makes it a favorable site for mercury (Hg) study. Various snow samples, such as surface snow, snow pit, and snowmelt water were collected from Mt. Yulong in the southeastern TP. The average concentration of Hg was found to be 37 ± 26 ng L-1 (mean ± SD), comparable to Hg concentration from other parts of TP in the same year, though it was comparatively higher than those from previous years, suggesting a possible increase of Hg concentration over the TP. The concentration of Hg was higher in the lower elevation of the glaciers possibly due to the surface melting concentration of particulates. Higher concentration of Hg was observed in the fresh snow, suggesting the possibility of long-range transportation. The average concentration of Hg from the snow pit was 1.49 ± 0.78 ng L-1, and the concentration of Hg in the vertical profile of the snow pit co-varied with calcium ion (Ca2+) supporting the fact that the portion of Hg is from the crustal origin. In addition, the principal component analysis (PCA) confirmed that the source of Hg is from the crustal origin; however, the presence of anthropogenic source in the Mt. Yulong was also observed. In surface water around Mt. Yulong, the concentration of HgT was found in the order of Lashihai Lake > Reservoirs > Rivers > Swamps > Luguhu Lake. In lake water, the concentration of HgT showed an increasing trend with depth. Overall, the increased concentration of Hg in recent years from the TP can be of concern and may have an adverse impact on the downstream ecosystem, wildlife, and human health.
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Affiliation(s)
- Rukumesh Paudyal
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Rd. 320, Lanzhou, 730000, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- Himalayan Environment Research Institute (HERI), Kathmandu, Nepal
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Rd. 320, Lanzhou, 730000, China.
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Rd. 320, Lanzhou, 730000, China
- Himalayan Environment Research Institute (HERI), Kathmandu, Nepal
| | - Junming Guo
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Rd. 320, Lanzhou, 730000, China
| | - Chhatra Mani Sharma
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Rd. 320, Lanzhou, 730000, China
- Himalayan Environment Research Institute (HERI), Kathmandu, Nepal
- Central Department of Environmental Science, Tribhuvan University, Kathmandu, Nepal
| | - Jie Huang
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Hewen Niu
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Rd. 320, Lanzhou, 730000, China
- Yulong Snow Mountain Glacier and Environmental Observation Research Station, State Key Laboratory of Cryospheric Science, Lanzhou, 730000, China
| | - Shiwei Sun
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Rd. 320, Lanzhou, 730000, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Tao Pu
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Donggang West Rd. 320, Lanzhou, 730000, China
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Tripathee L, Guo J, Kang S, Paudyal R, Huang J, Sharma CM, Zhang Q, Chen P, Ghimire PS, Sigdel M. Spatial and temporal distribution of total mercury in atmospheric wet precipitation at four sites from the Nepal-Himalayas. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 655:1207-1217. [PMID: 30577113 DOI: 10.1016/j.scitotenv.2018.11.338] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 11/22/2018] [Accepted: 11/23/2018] [Indexed: 06/09/2023]
Abstract
The studies on global pollutant mercury (Hg), which is of public concern due to its high toxicity and capacity to long-range transport via atmospheric circulation, is poorly characterized in wet deposition over the Nepal-Himalayas region. Therefore, in order to understand the concentration levels, spatial distribution and seasonal variation of total Hg, 333 precipitation samples were collected from south to north: Kathmandu (1314 m a.s.l.), Dhunche (2065 m a.s.l.), Dimsa (3078 m a.s.l.) and Gosainkunda (4417 m a.s.l.) characterized as urban, rural, remote forest and remote alpine sites, respectively, for over one-year period. The highest Hg concentration was found in Kathmandu comparable to the urban sites worldwide, and significantly lower concentrations at other three sites demonstrated similar levels as in rural and remote alpine sites worldwide. Higher wet deposition fluxes of 34.91 and 15.89 μg m-2 year-1 were found in Kathmandu and Dhunche respectively, due to higher precipitation amount. Clear and distinct seasonal differences were observed with higher concentrations in non-monsoon and lower values in monsoon periods due to less scavenging and high pollutant concentration loadings during the dry period. The positive correlation of Hg flux and precipitation amount with Hg concentration suggested that both precipitation amount and Hg concentration plays a vital role in Hg deposition in the central Himalayan region. Enrichment factor (EFHg) indicated that the anthropogenic emission sources play a significant role for Hg enrichment and a high ratio of EFmonsoon to EFnon-monsoon (>2.18) suggested that the anthropogenic atmospheric mercury could likely be long-range transported from south Asian regions to the Himalayas during the monsoon season. In addition, our results showed that the major ionic compositions (e.g., SO42-, NO3-, NH4+, K+, Ca2+) could influence Hg concentration in wet precipitation. The anthropogenic sources of Hg such as biomass and fossil fuel combustion, crustal aerosols may contribute to the Hg concentration in wet precipitation over the central Himalayas.
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Affiliation(s)
- Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Himalayan Environment Research Institute (HERI), Kathmandu, Nepal
| | - Junming Guo
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China.
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rukumesh Paudyal
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Himalayan Environment Research Institute (HERI), Kathmandu, Nepal; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jie Huang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China.
| | - Chhatra Mani Sharma
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Himalayan Environment Research Institute (HERI), Kathmandu, Nepal; Central Department of Environmental Science, Tribhuvan University, Kathmandu, Nepal
| | - Qianggong Zhang
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100085, China; Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Pengfei Chen
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China
| | - Prakriti Sharma Ghimire
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences (CAS), Lanzhou 730000, China; Himalayan Environment Research Institute (HERI), Kathmandu, Nepal
| | - Madan Sigdel
- Central Department of Hydrology and Meteorology, Tribhuvan University, Kathmandu, Nepal
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15
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Rehman Qaisar FU, Zhang F, Pant RR, Wang G, Khan S, Zeng C. Spatial variation, source identification, and quality assessment of surface water geochemical composition in the Indus River Basin, Pakistan. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:12749-12763. [PMID: 29470753 DOI: 10.1007/s11356-018-1519-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 02/08/2018] [Indexed: 05/12/2023]
Abstract
The Indus River Basin (IRB) with an area of 139,202 km2 is the lifeline river basin of Pakistan. An intensive study was conducted in six subcatchments of the IRB with five in the Upper Indus Basin (UIB) and one of the Lower Indus Basin (LIB; between Tarbela Dam and Panjand), i.e., the Gilgit River Basin (UIB-I), Hunza River Basin (UIB-II), UIB-III, UIB-IV and UIB-V, and LIB. A total of 84 surface water samples were collected from main stream and tributaries from June to August, 2016. The pH, electric conductivity (EC), and total dissolved solids (TDS) were measured in situ, whereas major ions (Ca2+, Mg2+, K+, Na+, Cl-, SO42-, and NO3-) and Si were analyzed in the laboratory. The results exhibited alkaline pH (8.55 ± 0.20) with diverse TDS (114.69 ± 77.65 mg L-1) and ion concentrations that were characterized primarily by the Ca-Mg-HCO3 type in the whole basin. The average TDS in the UIB and LIB were 93.99 ± 39.73 and 181.67 ± 167.82 mg L-1, respectively, under the influence of the arid to semi-arid climatic conditions and relatively higher anthropogenic interference in LIB compared to the UIB. The order of dominant major cations was different in the UIB and LIB, reflecting the diverse nature of geological formation. Gibbs plot, mixing diagrams, and ionic ratios were used to identify the controlling mechanism of river geochemistry in the IRB as carbonate weathering in general with different degrees of silicate weathering and minor contribution by evaporite dissolution. In addition, principal component/factor analysis also indicated that the major sources of dissolved loads in the basin are carbonates followed by silicates. Significant influences of silicate minerals were observed in the LIB, and there was a large contribution of evaporites in the UIB-II, UIB-III, and LIB. The suitability assessment showed that the river water fits the WHO permissible limits for drinking purposes from the perspective of major ions, whereas for irrigation purposes, most of the samples exhibited excellent and good levels except for a couple of permissible and doubtful levels from the Sawan and Deratang tributaries in the LIB, which may deteriorate the quality of soil and degrade the water quality downstream.
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Affiliation(s)
- Faizan Ur Rehman Qaisar
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
- Department of Earth Sciences COMSATS Institute of Information Technology, Abbottabad, Pakistan
| | - Fan Zhang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China.
- Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China.
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
| | - Ramesh Raj Pant
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
- Central Department of Environmental Science, Tribhuvan University, Kirtipur, Nepal
| | - Guanxing Wang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Sardar Khan
- Department of Environmental Sciences, University of Peshawar, Peshawar, Pakistan
| | - Chen Zeng
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
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16
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Pant RR, Zhang F, Rehman FU, Wang G, Ye M, Zeng C, Tang H. Spatiotemporal variations of hydrogeochemistry and its controlling factors in the Gandaki River Basin, Central Himalaya Nepal. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 622-623:770-782. [PMID: 29223904 DOI: 10.1016/j.scitotenv.2017.12.063] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 12/05/2017] [Accepted: 12/05/2017] [Indexed: 06/07/2023]
Abstract
The characterization and assessment of water quality in the head water region of Himalaya is necessary, given the immense importance of this region in sustaining livelihoods of people and maintaining ecological balance. A total of 165 water samples were collected from 55 sites during pre-monsoon, monsoon and post-monsoon seasons in 2016 from the Gandaki River Basin of the Central Himalaya, Nepal. The pH, EC values and TDS concentrations were measured in-situ and the concentrations of major ions (Ca2+, Mg2+, K+, Na+, Cl-, SO42-, NO3-) and Si were analyzed in laboratory. Correlation matrices, paired t-test, cluster analysis, principal component analysis (PCA), the Piper, Gibbs, and Mixing plots, and saturation index were applied to the measurements for evaluating spatiotemporal variation of the major ions. The results reveal mildly alkaline pH values and the following pattern of average ionic dominance: Ca2+>Mg2+>Na+>K+ for cations and HCO3->SO42->Cl->NO3- for anions. The results of PCA, Gibbs plot and the ionic relationships displayed the predominance of geogenic weathering processes in areas with carbonate dominant lithology. This conclusion is supported by geochemically different water facies identified in the Piper plot as Ca-HCO3 (83.03%), mixed Ca-Mg-Cl (12.73.0%) and Ca-Cl (4.24%). Pronounced spatiotemporal heterogeneity demonstrates the influence of climatic, geogenic and anthropogenic conditions. For instance, the Ca2+-SO42-, Mg2+-SO42- and Na+-Cl- pairs exhibit strong positive correlation with each other in the upstream region, whereas relatively weak correlation in the downstream region, likely indicating the influence of evapo-crystallization processes in the upstream region. Analyses of the suitability of the water supply for drinking and irrigation reveal that the river has mostly retained its natural water quality but poses safety concern at a few locations. Knowledge obtained through this study can contribute to the sustainable management of water quality in the climatically and lithologically distinct segments of the Himalayan river basins.
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Affiliation(s)
- Ramesh Raj Pant
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China; Central Department of Environmental Science, Tribhuvan University, Nepal
| | - Fan Zhang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China.
| | - Faizan Ur Rehman
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China; Department of Earth Sciences, COMSATS Institute of Information Technology, Abbottabad, Pakistan
| | - Guanxing Wang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Ming Ye
- Department of Earth, Ocean, and Atmospheric Science, Florida State University, Tallahassee, FL, USA
| | - Chen Zeng
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
| | - Handuo Tang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
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17
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Yang L, Zhu G, Shi P, Li J, Liu Y, Tong H, Hu P, Liang F, Pan H, Guo H, Zhang Y. Spatiotemporal characteristics of hydrochemistry in Asian arid inland basin-a case study of Shiyang River Basin. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:2293-2302. [PMID: 29119495 DOI: 10.1007/s11356-017-0504-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 10/17/2017] [Indexed: 06/07/2023]
Abstract
Inland rivers play a key role in supplying water for domestic and agricultural purposes in Asian arid inland basin. This paper investigates the chemical composition of precipitation, river water, and groundwater, providing evidence for the influencing factors the water composition in the Shiyang River Basin. Water samples were collected and analyzed to determine the content of major cations (Ca2+, Mg2+, Na+, K+, and NH+ 4) and anions (HCO- 3, Cl-, NO- 3, NO- 2, F-, and SO2-4), total solid solubility, and pH values. The results showed that precipitation, surface water, and groundwater were mildly alkaline. Ca2+ and SO2-4 were the predominant ions. The content of inorganic ions varied largely in the different seasons, with the highest ion concentration observed in spring and the lowest in summer. The seasonal variations in groundwater were less considerable than those in surface water. Furthermore, anion concentrations increased substantially from upstream to downstream. Regional weathering of carbonates and evaporation were established as the major sources of these ions. In addition, we discovered that anthropogenic inputs had led to light pollution of water in some residential districts.
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Affiliation(s)
- Ling Yang
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China
| | - Guofeng Zhu
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China.
- State Key Laboratory of Cryosphere Science, Northwest institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
| | - Peiji Shi
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China
| | - Jiafang Li
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China
| | - Yuanfeng Liu
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China
| | - Huali Tong
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China
| | - Pengfei Hu
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China
| | - Feng Liang
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China
| | - Hanxiong Pan
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China
| | - Huiwen Guo
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China
| | - Yu Zhang
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou, 730070, China
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Tripathee L, Kang S, Rupakheti D, Cong Z, Zhang Q, Huang J. Chemical characteristics of soluble aerosols over the central Himalayas: insights into spatiotemporal variations and sources. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:24454-24472. [PMID: 28895029 DOI: 10.1007/s11356-017-0077-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 09/01/2017] [Indexed: 06/07/2023]
Abstract
In order to investigate the spatial and temporal variations of aerosols and its soluble chemical compositions of the data gap zone in the central Himalayan region, aerosol samples were collected at four sites. The sampling location were characterized by four different categories, such as urban (Bode), semi-urban site in the northern Indo-Gangetic Plain (Lumbini), rural (Dhunche), and semiarid rural (Jomsom). A total of 230 aerosol samples were collected from four representative sites for a yearlong period and analyzed for water-soluble inorganic ions (WSIIs). The annual average aerosol mass concentration followed the sequence as Bode (238.24 ± 162.24 μg/m3)> Lumbini (161.14 ± 105.95 μg/m3)> Dhunche (112.40 ± 40.30 μg/m3)> Jomsom (78.85 ± 34.28 μg/m3), suggesting heavier particulate pollution in the urban and semi-urban sites. The total soluble ions contributed to 12.61-28.19% of TSP aerosol mass. The results revealed that SO42- and NO3- were the major anion and Ca2+ and NH4+ were the major cation influencing the aerosol composition over the central Himalayas. Calcium played a major role in neutralizing aerosol acidity followed by NH4+ at all the sites. The major compound of aerosol was (NH4)2SO4 and NH4HSO4 in the central Himalayas. Clear seasonality was observed at three observation sites, with higher concentrations during non-monsoon (dry periods) and lower during monsoon (wet period), suggesting washing out of aerosol particles by heavy precipitation during monsoon. In contrast, semiarid sites did not show the clear seasonal trend due to limited precipitation. Stationary sources were predominant over the mobile sources mostly in the remote sites. Principal component analysis confirmed that the major sources of WSIIs in the region were industrial emissions, fossil fuel and biomass burning, and crustal fugitive dusts. Nevertheless, transboundary aerosol transport over the region from polluted cities from south Asia could not be ignored as indicated by the clusters of air mass backward trajectory analysis.
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Affiliation(s)
- Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
- Himalayan Environment Research Institute (HERI), Kathmandu, Nepal.
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Dipesh Rupakheti
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese, Academy of Sciences, Beijing, 100101, China
| | - Zhiyuan Cong
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100101, China
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese, Academy of Sciences, Beijing, 100101, China
| | - Qianggong Zhang
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100101, China
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese, Academy of Sciences, Beijing, 100101, China
| | - Jie Huang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese, Academy of Sciences, Beijing, 100101, China
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Guo J, Kang S, Huang J, Zhang Q, Rupakheti M, Sun S, Tripathee L, Rupakheti D, Panday AK, Sillanpää M, Paudyal R. Characterizations of atmospheric particulate-bound mercury in the Kathmandu Valley of Nepal, South Asia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 579:1240-1248. [PMID: 27913014 DOI: 10.1016/j.scitotenv.2016.11.110] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 11/14/2016] [Accepted: 11/16/2016] [Indexed: 06/06/2023]
Abstract
The Kathmandu Valley, located in the Himalayan foothills in Nepal, is heavily polluted. In order to investigate ambient particulate-bound mercury (Hg) in the Kathmandu Valley, a total 64 total suspended particulates (TSP) samples were collected from a sub-urban site in the Kathmandu Valley, the capital region of Nepal during a sampling period of an entire year (April 2013-April 2014). They were analyzed for ambient particulate-bound Hg (PBM) using thermal desorption combined with cold vapor atomic spectroscopy. In our knowledge, it is the first study of ambient PMB in the Kathmandu Valley and the surrounding broader Himalayan foothill region. The average concentration of PBM over the entire sampling period of a year was found to be 850.5 (±962.8) pg m-3 in the Kathmandu Valley. This is comparable to those values reported in the polluted cities of China and significantly higher than those observed in most of urban areas in Asia and other regions of world. The daily average Hg contents in TSP (PBM/TSP) ranges from 269.7 to 7613.0ngg-1 with an average of 2586.0 (±2072.1) ng g-1, indicating the high enrichment of Hg in TSP. The average concentrations of PBM were higher in the winter and pre-monsoon season than in the monsoon and post-monsoon season. The temporal variations in the strength of anthropogenic emission sources combined with other influencing factors, such as ambient temperature and the removal of atmospheric aerosols by wet scavenging are attributable to the seasonal variations of PBM. The considerably high dry deposition flux of PBM estimated by using a theoretical model was 135μgm-2yr-1 at the Kathmandu Valley. This calls for an immediate attention to addressing ambient particulate Hg in the Kathmandu Valley, including considering it as a key component of future air quality monitoring activities and mitigation measures.
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Affiliation(s)
- Junming Guo
- Key Laboratory of Tibetan Environment Changs and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli, Finland; Graduate University of Chinese Academy of Sciences, Beijing 100039, China
| | - Shichang Kang
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Jie Huang
- Key Laboratory of Tibetan Environment Changs and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Qianggong Zhang
- Key Laboratory of Tibetan Environment Changs and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | | | - Shiwei Sun
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Graduate University of Chinese Academy of Sciences, Beijing 100039, China
| | - Lekhendra Tripathee
- Key Laboratory of Tibetan Environment Changs and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli, Finland
| | - Dipesh Rupakheti
- Key Laboratory of Tibetan Environment Changs and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Graduate University of Chinese Academy of Sciences, Beijing 100039, China
| | - Arnico K Panday
- International Centre for Integrated Mountain Development, Kathmandu, Nepal
| | - Mika Sillanpää
- Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli, Finland
| | - Rukumesh Paudyal
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; Graduate University of Chinese Academy of Sciences, Beijing 100039, China
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Tripathee L, Kang S, Sharma CM, Rupakheti D, Paudyal R, Huang J, Sillanpää M. Preliminary Health Risk Assessment of Potentially Toxic Metals in Surface Water of the Himalayan Rivers, Nepal. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 97:855-862. [PMID: 27734088 DOI: 10.1007/s00128-016-1945-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 10/05/2016] [Indexed: 06/06/2023]
Abstract
This study investigates the contamination levels and risk assessments of 14 elements (Ba, Cd, Co, Cr, Cu, Pb, Li, Mn, Mo, Ni, Sb, Sr, V and Zn) in three sub-basins of Himalayan rivers. Water samples were collected and the hazard quotient (HQ), hazard index (HI), and water quality index (WQI) were calculated. Total average concentrations of the metals were 135.03, 80.10 and 98.34 µg/L in Gandaki, Indrawati and Dudh Koshi rivers, respectively. The results of HQ and HI were less than unity, suggesting a low risk of metals in the region. However, HQ for antimony (Sb) was found to be 4.4 × 10-1, 2.1 × 10-1 and 5.4 × 10-1 in three river basins and HI near unity, suggesting its potential risk. Additionally, HI for Cd in Indrawati was 5.4 × 10-1 also close to unity, suggesting that Cd could have a potential risk to the local residents and aquatic ecosystems. Further, WQI suggested that the rivers Gandaki and Indrawati fell into the excellent water quality and river Dudh Koshi fell into good water quality.
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Affiliation(s)
- Lekhendra Tripathee
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
- Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130, Mikkeli, Finland
- Himalayan Environment Research Institute (HERI), Kathmandu, Nepal
| | - Shichang Kang
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Chhatra Mani Sharma
- Department of Environmental Science and Engineering, Kathmandu University, Dhulikhel, Nepal
- Himalayan Environment Research Institute (HERI), Kathmandu, Nepal
| | - Dipesh Rupakheti
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Rukumesh Paudyal
- State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
- Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130, Mikkeli, Finland
- Himalayan Environment Research Institute (HERI), Kathmandu, Nepal
| | - Jie Huang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
- Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130, Mikkeli, Finland
| | - Mika Sillanpää
- Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130, Mikkeli, Finland
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Huang J, Kang S, Tian L, Guo J, Zhang Q, Cong Z, Sillanpää M, Sun S, Tripathee L. Influence of long-range transboundary transport on atmospheric water vapor mercury collected at the largest city of Tibet. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 566-567:1215-1222. [PMID: 27265735 DOI: 10.1016/j.scitotenv.2016.05.177] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 05/23/2016] [Accepted: 05/25/2016] [Indexed: 06/05/2023]
Abstract
Monsoon circulation is an important process that affects long-range transboundary transport of anthropogenic contaminants such as mercury (Hg). During the Indian monsoon season of 2013, a total of 92 and 26 atmospheric water vapor samples were collected at Lhasa, the largest city of the Tibet, for Hg and major ions analysis, respectively. The relatively low pH/high electronic conductivity values, together with the fact that NH4(+) in atmospheric water vapor was even higher than that determined in precipitation of Lhasa, indicated the effects of anthropogenic perturbations through long-range transboundary atmospheric transport. Concentrations of Hg in atmospheric water vapor ranged from 2.5 to 73.7ngL(-1), with an average of 12.5ngL(-1). The elevated Hg and major ions concentrations, and electronic conductivity values were generally associated with weak acidic samples, and Hg mainly loaded with anthropogenic ions such as NH4(+). The results of principal component analysis and trajectory analysis suggested that anthropogenic emissions from the Indian subcontinent may have largely contributed to the determined Hg in atmospheric water vapor. Furthermore, our study reconfirmed that below-cloud scavenging contribution was significant for precipitation Hg in Lhasa, and evaluated that on average 74.1% of the Hg in precipitation could be accounted for by below-cloud scavenging.
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Affiliation(s)
- Jie Huang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China; Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, Mikkeli FI 50130, Finland
| | - Shichang Kang
- State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China.
| | - Lide Tian
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Junming Guo
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Qianggong Zhang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhiyuan Cong
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China
| | - Mika Sillanpää
- Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, Mikkeli FI 50130, Finland
| | - Shiwei Sun
- State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Lekhendra Tripathee
- State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China
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Water-Soluble Ionic Composition of Aerosols at Urban Location in the Foothills of Himalaya, Pokhara Valley, Nepal. ATMOSPHERE 2016. [DOI: 10.3390/atmos7080102] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Variations of the Physicochemical Parameters and Metal Levels and Their Risk Assessment in Urbanized Bagmati River, Kathmandu, Nepal. J CHEM-NY 2016. [DOI: 10.1155/2016/6025905] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
During post-monsoon 2013, surface water samples were collected form 34 sites from the Bagmati River and its tributaries within the Kathmandu Valley to assess the river water quality. The physical parameters were measured on site and major ions (Na+,NH4+, K+, Mg2+, Ca2+, Cl−,SO42-, andNO3-) and 17 elements in water were analyzed in the laboratory. Conductivity ranged from 21.92 to 846 μS/cm, while turbidity ranged from 2.52 to 223 NTU and dissolved oxygen (DO) ranged from 0.04 to 8.98 mg/L. The ionic and elemental concentrations were higher in the lower section where the population density is high compared to the headwaters. The large input of wastewater and organic load created anoxic condition by consuming dissolved oxygen along the lower belt of the river. The concentration of the elements was found to be in the order of Mn > Zn > Ti > Rb > Cr > Cu > Sc > Ni > V > Li > Co > Mo > Cd > Y > Ga > Be > Nb. The concentration of Mn, Cd, Cr, Co, and Zn was particularly higher in urban and semiurban sections. Enrichment factor (EF) calculations for Cd, Co, and Zn showed their highly enriched values indicating that these elements originated from anthropogenic sources. Preliminary risk assessments were determined by the hazard quotient (HQ) calculations in order to evaluate the health risk of the metals. TheHQingestionvalues of elements were found to be in the order Sb > Mn > Cr > V > Co > Cd > Cu > Zn > Ni > Li > Mo with all averaged HQ values less than 1, indicating no or limited health risk of metals from the river to the local residence. However the values of Sb in some parts of the Bagmati were close to unity indicating its possible threat. Anthropogenic activities like industrial activities, municipal waste water, and road construction besides the river appear to control the chemical constituent of the river water. Overall the river was highly polluted with elevated concentrations of major ions and elements and there is a need for restoration projects.
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