1
|
Nguyen MY, Vanreusel A, Lins L, Thanh TT, Bezerra TN, Nghia SH, Ngo Xuan Q. Nematode's morphometric shifts related to changing environmental conditions in the Mekong estuaries Ba Lai and Ham Luong, Vietnam. Environ Sci Pollut Res Int 2023:10.1007/s11356-023-27399-y. [PMID: 37160517 DOI: 10.1007/s11356-023-27399-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 04/29/2023] [Indexed: 05/11/2023]
Abstract
Damming has been reported to give many short-term benefits for local people but also to result in long-term negative impacts on the aquatic ecosystem. The ecological impact of the Ba Lai dam was studied by investigating environmental differences and the response of associated aquatic nematode communities (structure and morphometric characteristics) in both downstream and upstream sections of its estuary in comparison to an adjacent dam-free estuary Ham Luong, both belonging to the Mekong delta in Vietnam. Depleted dissolved oxygen, elevated methane and sulfide concentrations and increased accumulation of contaminants, including total suspended solid, heavy metals, and nutrients in the dammed estuary and its upstream section, indicated an impact of the dam on the environment. The dammed estuary showed differences in the nematode communities inhabiting the subtidal sediments from the reference estuary such as a higher nematode individual biomass with smaller length/width ratio as a consequence of the larger body width. The absence of long/thin nematodes in the dammed estuary, but high abundance of a slender nematode morphotype, a group with a higher efficiency of obtaining dissolved oxygen as a consequence of their comparatively large surface/volume ratio, might represent an adaptation of those communities to live in poor oxygen condition. In the dammed estuary, the small L/W ratio of nematode communities was potentially driven by the interaction effects of enrichment of both total suspended solid and ammonium linked to dissolved oxygen depletion. These findings support the potential use of nematode communities as bioindicators in ecological quality assessment although plausible; it is not possible to ascertain if only the dam causes the changes in the nematode communities.
Collapse
Affiliation(s)
- My Yen Nguyen
- Department of Environmental Management and Technology, Institute of Tropical Biology, Vietnam Academy of Science and Technology, 85, Tran Quoc Toan, Dist.3, Ho Chi Minh City, Vietnam
- Marine Biology Research Group, Biology Department, Ghent University, Krijgslaan 281, S8, B-9000, Ghent, Belgium
| | - Ann Vanreusel
- Marine Biology Research Group, Biology Department, Ghent University, Krijgslaan 281, S8, B-9000, Ghent, Belgium
| | - Lidia Lins
- Marine Biology Research Group, Biology Department, Ghent University, Krijgslaan 281, S8, B-9000, Ghent, Belgium
| | - Thai Tran Thanh
- Department of Environmental Management and Technology, Institute of Tropical Biology, Vietnam Academy of Science and Technology, 85, Tran Quoc Toan, Dist.3, Ho Chi Minh City, Vietnam
| | - Tania Nara Bezerra
- Marine Biology Research Group, Biology Department, Ghent University, Krijgslaan 281, S8, B-9000, Ghent, Belgium
| | - Son Hoang Nghia
- Department of Environmental Management and Technology, Institute of Tropical Biology, Vietnam Academy of Science and Technology, 85, Tran Quoc Toan, Dist.3, Ho Chi Minh City, Vietnam
| | - Quang Ngo Xuan
- Department of Environmental Management and Technology, Institute of Tropical Biology, Vietnam Academy of Science and Technology, 85, Tran Quoc Toan, Dist.3, Ho Chi Minh City, Vietnam.
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Street, Cau Giay District, Hanoi, Vietnam.
| |
Collapse
|
2
|
Ghimire S, Shrestha S, Hok P, Heng S, Nittivattanaon V, Sabo J. Integrated assessment of climate change and reservoir operation on flow-regime and fisheries of the Sekong river basin in Lao PDR and Cambodia. Environ Res 2023; 220:115087. [PMID: 36566963 DOI: 10.1016/j.envres.2022.115087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 11/22/2022] [Accepted: 12/14/2022] [Indexed: 06/17/2023]
Abstract
This study assesses the cumulative impact of climate change and reservoir operation on flow regime and fisheries in the Sekong River Basin. Ensemble of five selected Regional Climate Models (RCMs) were used to project the future climate under RCP4.5 and RCP8.5 scenarios. The projected future climate was used to simulate the future hydrology using the SWAT model while HEC-ResSim was utilized for reservoir simulation. Finally fish-flow relationship was developed to estimate the fish catch and productivity in future. Upon investigation we found that, Sekong River Basin is likely grow warmer and drier in future under climate change. The basin is expected to face 1.3-3.6 °C rise in mean annual temperature and receive 0-6% less annual rainfall in future. The wet season in the basin is anticipated to be drier (0% to -6%) while the dry season rainfall shows no particular trend (-3%-10%). Such a change in climate is likely to alter the mean annual flow in future between -3 and 5% at Attapeu, -6 to 2% at Ban Veunkhane, Lao PDR, and -7 to 1% at Siempang, Cambodia (basin outlet). Under climate change, we expect decrement in minimum flow but increment in the maximum flow while opposite is anticipated under reservoir operation. Operation of Xekaman 1 and Sekong 4A are likely to increase the minimum flow at river outlet by 32-59% and 13-18% respectively whereas maximum flow is expected to decrease by 28-5%. In addition, climate change is likely to have crucial impact on fisheries with up to 19% and 12% reduction in fish catches and fish productivity respectively. However, reservoirs tend to have negligible impact on fisheries.
Collapse
Affiliation(s)
- Suwas Ghimire
- Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathum Thani, 12120, Thailand
| | - Sangam Shrestha
- Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathum Thani, 12120, Thailand.
| | - Panha Hok
- Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathum Thani, 12120, Thailand
| | - Sokchhay Heng
- Institute of Technology of Cambodia, Faculty of Hydrology and Water Resources Engineering, Cambodia
| | - Vilas Nittivattanaon
- Urban Environment Management, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathum Thani, 12120, Thailand
| | - John Sabo
- School of Life Sciences, Arizona State University, 330 E University Drive, PO Box 877205, Tempe, AZ, 85281-7205, USA
| |
Collapse
|
3
|
Kang H, Sridhar V, Ali SA. Climate change impacts on conventional and flash droughts in the Mekong River Basin. Sci Total Environ 2022; 838:155845. [PMID: 35561902 DOI: 10.1016/j.scitotenv.2022.155845] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 04/27/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
Recent drought events in the Mekong River Basin (MRB) have resulted in devastating environmental and economic losses, and climate change and human-induced alterations have exacerbated drought conditions. Using hydrologic models and multiple climate change scenarios, this study quantified the future climate change impacts on conventional and flash drought conditions in the MRB. The Soil and Water Assessment Tool (SWAT) and Variable Infiltration Capacity (VIC) models were applied to estimate long-term drought indices for conventional and flash drought conditions over historical and future periods (1966-2099), using two emission scenarios (RCP 4.5 and RCP8.5), and four climate models from the Coupled Model Intercomparison Project Phase 5 (CMIP5). For the conventional drought assessment, monthly scale drought indices were estimated, and pentad-scale (5 days) drought indices were computed for the flash drought evaluations. There were overall increases in droughts from the SWAT model for the conventional drought conditions and overall decreases from the VIC model. For the flash drought conditions, the SWAT-driven drought indices showed overall increases in drought occurrences (up to 165%). On the contrary, the VIC-driven drought indices presented decreases in drought occurrences (up to -44%). The conventional and flash drought evaluations differ between these models as they partition the water budget, specifically soil moisture differently. We conclude that the proposed framework, which includes hydrologic models, various emission scenarios, and projections, allows us to assess the various perspectives on drought conditions. Basin countries have differential impacts, so targeted future adaptation strategy is required.
Collapse
Affiliation(s)
- Hyunwoo Kang
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
| | - Venkataramana Sridhar
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
| | - Syed A Ali
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
| |
Collapse
|
4
|
Chen A, Chen A, Varis O, Chen D. Large net forest loss in Cambodia's Tonle Sap Lake protected areas during 1992-2019. Ambio 2022; 51:1889-1903. [PMID: 35133565 PMCID: PMC9200915 DOI: 10.1007/s13280-022-01704-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 09/25/2021] [Accepted: 01/10/2022] [Indexed: 06/14/2023]
Abstract
Historical land-use practices have caused forest loss in Cambodia's Tonle Sap Lake area (TSLA), the largest freshwater lake in Southeast Asia. However, it remains unclear if this deforestation trend had continued since 2001 when the land was designated as protected areas. Using satellite imagery, we investigated forest conversion flows and fragmentation patterns in the TSLA for 1992-2001, 2001-2010, and 2010-2019, respectively. Results show substantial forest losses and fragmentations occurring at the lower floodplain where the protected areas are located until 2010, with some forest regain during 2010-2019. The land conversions indicated that forest clearing and agricultural farming were the primary causes for observed extensive forest loss during 1992-2010. Hence, despite the creating of protected areas in 2001, our findings reveal the persistence of alarming forest loss in the TSLA until 2010. On the other hand, while net forest loss has stopped after 2010, forest regain during 2010-2019 is way too small to restore the region's total forest area to even the level when the protected areas were established. Thus, more effective planning and implementations of forest management and restoration policies are needed for the TSLA.
Collapse
Affiliation(s)
- Aifang Chen
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055 China
- Regional Climate Group, Department of Earth Sciences, University of Gothenburg, Box 460, 40530 Gothenburg, Sweden
| | - Anping Chen
- Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523 USA
| | - Olli Varis
- Water and Development Research Group, Aalto University, 15200 Espoo, Finland
| | - Deliang Chen
- Regional Climate Group, Department of Earth Sciences, University of Gothenburg, Box 460, 40530 Gothenburg, Sweden
| |
Collapse
|
5
|
McPake B, Gilbert K, Vong S, Ros B, Has P, Khuong AT, Phuc PD, Hoang QC, Nguyen DH, Siengsounthone L, Luangphaxay C, Annear P, McKinley J. Role of regulatory capacity in the animal and human health systems in driving response to zoonotic disease outbreaks in the the Mekong region. One Health 2022; 14:100369. [PMID: 35106358 PMCID: PMC8784321 DOI: 10.1016/j.onehlt.2022.100369] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 12/29/2021] [Accepted: 01/03/2022] [Indexed: 11/19/2022] Open
Abstract
We conducted a policy situation analysis in three Mekong region countries, focused on how the animal and human health systems interact to control avian influenza (AI). The study used scoping literature reviews aimed at establishing existing knowledge concerning the regulatory context. We then conducted a series of key informant interviews with national and sub-national government officials and representatives of producers and poultry farmers to understand their realities in managing the complex interface of the two sectors to control AI. We found signs of formal progress in establishing the policy and legislative frameworks needed to enable cooperation of the two sectors but a series of constraints that impede their effective operation. These included the competitive relationships involved, especially with budgetary allocations and mandates that can conflict with each other. Many local actors also view development partners (e.g., bilateral and multilateral donors) as having a dominant role in establishing these collaborations, limiting the extent to which there is local ownership of the agenda. The animal and human health sectors are not equally resourced, with the animal health sector disadvantaged in terms of surveillance and laboratory systems, human resources and financial allocations. Contrasting strategies for achieving objectives have also characterised the two sectors in recent decades, seeing a major shift towards the use of incentive-based approaches in the human health sector but very little parallel development in the animal health sector, largely dependent on command and control approaches. Successful future collaborations between the two sectors are likely to depend on better resourcing in the animal health sector, increasing local ownership of the agenda, and ensuring that both sectors can use the full range of regulatory strategies available to achieve objectives.
Collapse
Affiliation(s)
- Barbara McPake
- Nossal Institute for Global Health, Melbourne, Australia
| | | | - Sreytouch Vong
- Independent consultants contracted by the Nossal Institute for Global Health, Phnom Penh, Cambodia
| | - Bandeth Ros
- Independent consultants contracted by the Nossal Institute for Global Health, Phnom Penh, Cambodia
| | - Phalmony Has
- National Institute of Public Health, Phnom Penh, Cambodia
| | | | - Pham-Duc Phuc
- Center for Public Health and Ecosystem Research, Hanoi University of Public Health, Hanoi, Viet Nam
| | | | - Duc Hai Nguyen
- Pasteur Institute Ho Chi Minh City, Ho Chi Minh City, Viet Nam
| | | | | | - Peter Annear
- Nossal Institute for Global Health, Melbourne, Australia
| | | |
Collapse
|
6
|
Singh SR, Teo AKJ, Prem K, Ong RTH, Ashley EA, van Doorn HR, Limmathurotsakul D, Turner P, Hsu LY. Epidemiology of Extended-Spectrum Beta-Lactamase and Carbapenemase-Producing Enterobacterales in the Greater Mekong Subregion: A Systematic-Review and Meta-Analysis of Risk Factors Associated With Extended-Spectrum Beta-Lactamase and Carbapenemase Isolation. Front Microbiol 2021; 12:695027. [PMID: 34899618 PMCID: PMC8661499 DOI: 10.3389/fmicb.2021.695027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 10/25/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Despite the rapid spread of extended-spectrum beta-lactamase (ESBL) producing-Enterobacterales (ESBL-E) and carbapenemase-producing Enterobacterales (CPE), little is known about the extent of their prevalence in the Greater Mekong Subregion (GMS). In this systematic review, we aimed to determine the epidemiology of ESBL-E and CPE in clinically significant Enterobacterales: Escherichia coli and Klebsiella pneumoniae from the GMS (comprising of Cambodia, Laos, Myanmar, Thailand, Vietnam and Yunnan province and Guangxi Zhuang region of China). Methods: Following a list of search terms adapted to subject headings, we systematically searched databases: Medline, EMBASE, Scopus and Web of Science for articles published on and before October 20th, 2020. The search string consisted of the bacterial names, methods involved in detecting drug-resistance phenotype and genotype, GMS countries, and ESBL and carbapenemase detection as the outcomes. Meta-analyses of the association between the isolation of ESBL from human clinical and non-clinical specimens were performed using the "METAN" function in STATA 14. Results: One hundred and thirty-nine studies were included from a total of 1,513 identified studies. Despite the heterogeneity in study methods, analyzing the prevalence proportions on log-linear model scale for ESBL producing-E. coli showed a trend that increased by 13.2% (95%CI: 6.1-20.2) in clinical blood specimens, 8.1% (95%CI: 1.7-14.4) in all clinical specimens and 17.7% (95%CI: 4.9-30.4) increase in carriage specimens. Under the log-linear model assumption, no significant trend over time was found for ESBL producing K. pneumoniae and ESBL-E specimens. CPE was reported in clinical studies and carriage studies past 2010, however a trend could not be determined because of the small dataset. Twelve studies were included in the meta-analysis of risk factors associated with isolation of ESBL. Recent antibiotic exposure was the most studied variable and showed a significant positive association with ESBL-E isolation (pooled OR: 2.9, 95%CI: 2.3-3.8) followed by chronic kidney disease (pooled OR: 4.7, 95%CI: 1.8-11.9), and other co-morbidities (pooled OR: 1.6, 95%CI: 1.2-2.9). Conclusion: Data from GMS is heterogeneous with significant data-gaps, especially in community settings from Laos, Myanmar, Cambodia and Yunnan and Guangxi provinces of China. Collaborative work standardizing the methodology of studies will aid in better monitoring, surveillance and evaluation of interventions across the GMS.
Collapse
Affiliation(s)
- Shweta R. Singh
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Alvin Kuo Jing Teo
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Kiesha Prem
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
- Department of Infectious Disease Epidemiology, Centre for Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Rick Twee-Hee Ong
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Elizabeth A. Ashley
- Lao-Oxford-Mahosot Hospital Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Laos
- Nuffield Department of Clinical Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
| | - H. Rogier van Doorn
- Nuffield Department of Clinical Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
- Oxford University Clinical Research Unit, Hanoi, Vietnam
| | - Direk Limmathurotsakul
- Nuffield Department of Clinical Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Paul Turner
- Nuffield Department of Clinical Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
- Cambodia Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
| | - Li Yang Hsu
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| |
Collapse
|
7
|
Schmitt RJP, Giuliani M, Bizzi S, Kondolf GM, Daily GC, Castelletti A. Strategic basin and delta planning increases the resilience of the Mekong Delta under future uncertainty. Proc Natl Acad Sci U S A 2021; 118:e2026127118. [PMID: 34475204 DOI: 10.1073/pnas.2026127118] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 07/27/2021] [Indexed: 11/18/2022] Open
Abstract
Globally, river deltas, which support some of the planet’s most productive agroeconomic systems and half a billion livelihoods, are at risk of being drowned by rising sea levels and accelerated subsidence. Whether delta land falls below sea level will depend on land and water management in the delta, sediment supply from the upstream basin, and global climate change. Those drivers cover multiple scales and domains and are rapidly changing, uncertain, and interconnected, which makes finding robust strategies to increase the resilience of river deltas challenging. Herein, we demonstrate an approach to identify planning levers that can increase the resilience of river deltas under a wide range of future conditions for the 40,000-km2 Mekong Delta in Southeast Asia. The climate resilience of river deltas is threatened by rising sea levels, accelerated land subsidence, and reduced sediment supply from contributing river basins. Yet, these uncertain and rapidly changing threats are rarely considered in conjunction. Here we provide an integrated assessment, on basin and delta scales, to identify key planning levers for increasing the climate resilience of the Mekong Delta. We find, first, that 23 to 90% of this unusually productive delta might fall below sea level by 2100, with the large uncertainty driven mainly by future management of groundwater pumping and associated land subsidence. Second, maintaining sediment supply from the basin is crucial under all scenarios for maintaining delta land and enhancing the climate resilience of the system. We then use a bottom-up approach to identify basin development scenarios that are compatible with maintaining sediment supply at current levels. This analysis highlights, third, that strategic placement of hydropower dams will be more important for maintaining sediment supply than either projected increases in sediment yields or improved sediment management at individual dams. Our results demonstrate 1) the need for integrated planning across basin and delta scales, 2) the role of river sediment management as a nature-based solution to increase delta resilience, and 3) global benefits from strategic basin management to maintain resilient deltas, especially under uncertain and changing conditions.
Collapse
|
8
|
Schnitzler JG, Das K, Wohlsein P, Kuiken T, Ludwig A, Lieckfeldt D, Phan C, Phay S, Siebert U. The Irrawaddy dolphin, Orcaella brevirostris from the Mekong river Cambodia: Preliminary health and toxicological investigations. Aquat Toxicol 2021; 234:105812. [PMID: 33799112 DOI: 10.1016/j.aquatox.2021.105812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 03/09/2021] [Accepted: 03/16/2021] [Indexed: 06/12/2023]
Abstract
The subpopulation of the Irrawaddy dolphin (Orcaella brevirostris) living in the Mekong River, Cambodia, is considered to be critically endangered. The aim of the investigation was to gain information about the genetic variation, health status and exposure to toxic compounds of these dolphins. Tissue samples from 27 Irrawaddy river dolphins found dead along the Mekong River between 2004 and 2009 were analysed with regards to genetics, pathology and ecotoxicology. Genetic maternal lineage detection, based on polymorphisms of the mitochondrial d-loop sequences, was performed. Data indicate a genetic separation of the Mekong dolphins from both the coastal population and the Mahakam dolphins. Pathological investigations revealed acute moderate multifocal suppurative bronchopneumonia, moderate periportal hepatic lipidosis, moderate diffuse hepatic atrophy and acute severe diffuse suppurative leptomeningitis. Residue levels of organochlorines and polybrominated diphenyl ethers in Irrawaddy dolphins from the Mekong River were lower than the concentrations reported for other cetaceans in the coastal and riverine waters of Asia, except for Dichlorodiphenyltrichloroethane. A high percentage of organic mercury compared to the immuno-toxic methylmercury was observed. Due to numerous confounding factors, it is not possible to relate levels of pollutants to observed morphological lesions. However, it is likely that chemical contaminants do adversely impact on the health of the Irrawaddy dolphins at present, and have also affected previous generations.
Collapse
Affiliation(s)
- Joseph G Schnitzler
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover, Werftstr. 6, 25761 Büsum, Germany.
| | - Krishna Das
- Freshwater and Oceanic Sciences Unit of research (FOCUS-Oceanology), University of Liege, Belgium
| | - Peter Wohlsein
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, 30559 Hannover, Germany
| | - Thijs Kuiken
- Department of Virology, Erasmus MC, P.O. Box 2040, 3000 CA Rotterdam, the Netherlands
| | - Arne Ludwig
- Leibniz-Institut für Zoo- und Wildtierforschung (IZW), Alfred-Kowalke-Straße 17, 10315 Berlin, Germany
| | - Dietmar Lieckfeldt
- Leibniz-Institut für Zoo- und Wildtierforschung (IZW), Alfred-Kowalke-Straße 17, 10315 Berlin, Germany
| | | | | | - Ursula Siebert
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover, Werftstr. 6, 25761 Büsum, Germany
| |
Collapse
|
9
|
Gunawardana SK, Shrestha S, Mohanasundaram S, Salin KR, Piman T. Multiple drivers of hydrological alteration in the transboundary Srepok River Basin of the Lower Mekong Region. J Environ Manage 2021; 278:111524. [PMID: 33126187 DOI: 10.1016/j.jenvman.2020.111524] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 10/10/2020] [Accepted: 10/15/2020] [Indexed: 06/11/2023]
Abstract
Human-induced changes in land and water resources adversely affect global hydrological regimes. Hydrological alteration of the natural flow regime is considered to have a significant damaging and widespread impact on river ecosystems and livelihoods. Therefore, understanding the hydrological alteration of rivers and the potential driving factors affecting such alterations are crucial to effective water resources management. This study analyses the impact of changes in land use, climate, and hydropower development on the hydrological regime of the Srepok River Basin in the Lower Mekong Region. The Lower Mekong Basin (LMB) in Southeast Asia is known for its agriculture, forests, fisheries, wildlife, and diverse natural ecosystems. Historical land use and climate change are quantified (utilising European Space Agency land cover and observed meteorological data) and correlated with the hydrological indicators using the Indicators of Hydrologic Alteration (IHA) software. Moreover, pre and post impacts on the hydrological regime by hydropower development are quantified using the Range of Variability Approach (RAV) in IHA software. The results reveal that land use, rainfall, and temperature affect different aspects of the hydrological regime, with corroborating evidence to support variation among the most correlated IHA and environmental flow component (EFC) parameters with the three drivers. The highest and lowest correlations among the IHA and EFC parameters under each driver are against land use (0.85, -0.83), rainfall (0.78, -0.54), and minimum and max temperatures (0.42, -0.47). Among the parameters, the fall rate has the most significant effect on hydrological alteration of all drivers. Hydropower development in the basin mostly affects the fall rate and reversal. Identifying the connection between these multiple drivers and hydrological alteration could help decision-makers to design more efficient and sustainable water management policies.
Collapse
Affiliation(s)
- Shakthi K Gunawardana
- Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology, P.O. Box 4 Klong Luang, Pathum Thani, 12120, Thailand
| | - Sangam Shrestha
- Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology, P.O. Box 4 Klong Luang, Pathum Thani, 12120, Thailand; Stockholm Environment Institute, Asia Centre, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand.
| | - S Mohanasundaram
- Water Engineering and Management, School of Engineering and Technology, Asian Institute of Technology, P.O. Box 4 Klong Luang, Pathum Thani, 12120, Thailand
| | - Krishna R Salin
- Aquaculture and Aquatic Resources Management, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4 Klong Luang, Pathum Thani, 12120, Thailand
| | - Thanapon Piman
- Stockholm Environment Institute, Asia Centre, Chulalongkorn University, Pathumwan, Bangkok, 10330, Thailand
| |
Collapse
|
10
|
Liu Z, Yao Z, Wang R, Yu G. Estimation of the Qinghai-Tibetan Plateau runoff and its contribution to large Asian rivers. Sci Total Environ 2020; 749:141570. [PMID: 32841858 DOI: 10.1016/j.scitotenv.2020.141570] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 08/06/2020] [Accepted: 08/06/2020] [Indexed: 06/11/2023]
Abstract
The Qinghai-Tibetan Plateau (QTP), named the Asian Water Towers, feeds more than 2.5 billion people in downstream regions. It is still unknown how much water outflows from this region owing to lack of observations. The main objective of this study is to clarify availability of water flowed out of this region and its contribution to large Asian rivers. The Global Land Data Assimilation System (GLDAS) products are evaluated with the help of observations of the QTP. In addition, a velocity-based routing method is embedded into the GLDAS model to route runoff products to the basin outlet in this study. The results show that the simulated dry season runoff in the GLDAS model is generally lower than the observed value, which is mainly because most hydrological models only consider the potential evapotranspiration (ET) when simulating ET, while ignoring the water constraint factor. Noah10_v2.0 has the highest precision at the QTP. For the monthly precipitation and runoff series, the relative error is within 5%, the correlation coefficient is greater than 0.90, and the Nash-Sutcliffe efficiencies are 0.95 and 0.76, respectively. Glacier melt runoff plays an important role in the QTP runoff, with a proportion of approximately 22%. It is relatively high in the Tarim River basin (83%), Syr Darya River and Amu Darya River basins (69%), and Indus River basin (60%). The contribution ratio also reaches 23% in the Yarlung Zangbo-Brahmaputra River and Ganges River basins, whereas it is the lowest in the Irrawaddy River basin (2%). According to the Noah10_v2.0 simulations, the mean annual runoff provided by the QTP exceeds 620 billion cubic metres, of which approximately 440 billion cubic metres flow out of the QTP and supply downstream regions of international rivers. The contribution ratio of the QTP runoff to the total runoff of its affected basins is approximately 16%.
Collapse
Affiliation(s)
- Zhaofei Liu
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101 Beijing, China.
| | - Zhijun Yao
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101 Beijing, China
| | - Rui Wang
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101 Beijing, China
| | - Guoan Yu
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101 Beijing, China.
| |
Collapse
|
11
|
Do P, Tian F, Zhu T, Zohidov B, Ni G, Lu H, Liu H. Exploring synergies in the water-food-energy nexus by using an integrated hydro-economic optimization model for the Lancang- Mekong River basin. Sci Total Environ 2020; 728:137996. [PMID: 32570321 DOI: 10.1016/j.scitotenv.2020.137996] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 03/02/2020] [Accepted: 03/15/2020] [Indexed: 06/11/2023]
Abstract
The Water-Food-Energy nexus study identifies developmental challenges and trade-offs present along the transboundary river basins. Intensive reservoir development for hydropower production impacts existing actors in the Lancang-Mekong River Basin. Concerns from these stakeholders highlight three major trade-offs that occur between hydropower and irrigation (HP-AG), hydropower and fisheries (HP-F), and irrigation and fisheries (AG-F). Dam construction has an impact not only on power production but also on ecosystems and ultimately the livelihood of people. In this study, we quantify the effects of reservoir operation on hydropower generation, irrigated crop production and fisheries yield in the Tonle Sap lake through a novel hydro-economic model at the whole basin scale. Our main finding is that trade-offs can be turned into synergetic opportunities. First, the dam operation can increase water availability for irrigation without severely harming hydropower production, raising irrigated crop revenue by 49% and reducing crop losses during droughts by 30%. Second, eco-friendly management increases fisheries yield by up to 75%, but decreases both irrigated crop production (-48%) and power production (-17%). Reservoirs can, therefore, benefit the whole basin by releasing more water in months with high irrigation demand (April and December) and by minimizing the adverse effects of flow fluctuations on the livelihood of farmers and fishers living downstream. Our results also reveal the overlooked trade-off between irrigated agriculture and fisheries. Cross-sectoral and transboundary partnerships should strengthen stakeholder participation in decision-making. Local solutions such as enhanced reservoir operation can respond to the broader global issue of natural resource trade-offs and sharing. Our alternative narrative enhances the dialogue about fair and efficient water use among Mekong riparian countries.
Collapse
Affiliation(s)
- Pierre Do
- Department of Hydraulic Engineering, State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China.
| | - Fuqiang Tian
- Department of Hydraulic Engineering, State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China.
| | - Tingju Zhu
- ZJU-UIUC Institute, International Campus, Zhejiang University, Haining 314400, China.
| | - Bahtiyor Zohidov
- Department of Hydraulic Engineering, State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China
| | - Guangheng Ni
- Department of Hydraulic Engineering, State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China.
| | - Hui Lu
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084, China.
| | - Hui Liu
- China Institute of Water Resources and Hydropower Research, Beijing 100048, China
| |
Collapse
|
12
|
Abstract
Hydropower has come to be treated as synonymous with sustainable economic development by many in the development arena. This is despite the adverse ecological and sociological impacts being widely recognised by those outside of decision-making. The prevalence of this 'hydropower myth' simplifies the complex trade-offs involved within hydropower development and often leads to inequitable situations and ecological damage. The Mekong River is used to demonstrate the strength of the hydropower myth-the disconnect with the social and ecological realities of the basin, and emerging and potential negative consequences. The attractiveness of the hydropower myth to decision-makers and developers is shown to lie largely in its political utility in bolstering national power and legitimacy as well as its ability to channel economic benefits towards states and developers.
Collapse
Affiliation(s)
- Jessica M Williams
- Faculty of Social Science, The University of Hong Kong, Pokfulam Road, Pokfulam, Hong Kong.
| |
Collapse
|
13
|
Abstract
In recent decades, scientists have developed a wide array of hydrological, hydrodynamic, and other models to understand the dynamics of the Mekong River Basin. Indeed, the area has been described as 'flooded' with models. Drawing on STS and the philosophy of modeling - which has described models as mediating instruments - the first half of this article discusses how and why this proliferation has occurred, focusing on the Cambodian context. Highlighting that models are developed comparatively, with reference to one another, the analysis shows how they have generated a partially connected ecology of comparisons. As each model makes its own image of the Mekong, the ecology as a whole creates a kaleidoscopic effect. In principle, this ecology is important for that of environmental policy-making. In practice, however, it is tremendously difficult for scientists to bridge the ecologies. Examining two cases of NGO-based modeling aiming to influence policy, the second half of the paper offers a comparative analysis of the challenges modeling knowledge faces in Mekong environmental politics.
Collapse
|
14
|
Ly S, Fortas C, Duong V, Benmarhnia T, Sakuntabhai A, Paul R, Huy R, Sorn S, Nguon K, Chan S, Kimsan S, Ong S, Kim KS, Buoy S, Voeung L, Dussart P, Buchy P, Tarantola A. Asymptomatic Dengue Virus Infections, Cambodia, 2012-2013. Emerg Infect Dis 2019; 25:1354-1362. [PMID: 31211672 PMCID: PMC6590774 DOI: 10.3201/eid2507.181794] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
We investigated dengue virus (DENV) and asymptomatic DENV infections in rural villages of Kampong Cham Province, Cambodia, during 2012 and 2013. We conducted perifocal investigations in and around households for 149 DENV index cases identified through hospital and village surveillance. We tested participants 0.5-30 years of age by using nonstructural 1 rapid tests and confirmed DENV infections using quantitative reverse transcription PCR or nonstructural 1-capture ELISA. We used multivariable Poisson regressions to explore links between participants' DENV infection status and household characteristics. Of 7,960 study participants, 346 (4.4%) were infected with DENV, among whom 302 (87.3%) were <15 years of age and 225 (65.0%) were <9 years of age. We identified 26 (7.5%) participants with strictly asymptomatic DENV infection at diagnosis and during follow-up. We linked symptomatic DENV infection status to familial relationships with index cases. During the 2-year study, we saw fewer asymptomatic DENV infections than expected based on the literature.
Collapse
Affiliation(s)
| | | | - Veasna Duong
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Tarik Benmarhnia
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Anavaj Sakuntabhai
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Richard Paul
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Rekol Huy
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Sopheak Sorn
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Kunthy Nguon
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Siam Chan
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Souv Kimsan
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Sivuth Ong
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Kim Srorn Kim
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Sowathy Buoy
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Lim Voeung
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | - Philippe Dussart
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia (S. Ly, C. Fortas, V. Duong, S. Sorn, K. Nguon, S. Chan, S. Kimsan, S. Ong, P. Dussart, P. Buchy, A. Tarantola)
- University of California, San Diego, California, USA (T. Benmarhnia)
- Institut Pasteur, Paris, France (A. Sakuntabhai, R. Paul)
- Malaria National Center, Phnom Penh (R. Huy)
- Kampong Cham Provincial Hospital, Kampong Cham, Cambodia (K.S. Kim)
- Prey Chhor District Referral Hospital, Kampong Cham (S. Buoy)
- Tboung Khmum District Referral Hospital, Thoung Khmum, Cambodia (L. Voeung)
| | | | | |
Collapse
|
15
|
Suttie A, Karlsson EA, Deng YM, Hurt AC, Greenhill AR, Barr IG, Dussart P, Horwood PF. Avian influenza in the Greater Mekong Subregion, 2003-2018. Infect Genet Evol 2019; 74:103920. [PMID: 31201870 DOI: 10.1016/j.meegid.2019.103920] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 05/20/2019] [Accepted: 06/11/2019] [Indexed: 12/15/2022]
Abstract
The persistent circulation of avian influenza viruses (AIVs) is an ongoing problem for many countries in South East Asia, causing large economic losses to both the agricultural and health sectors. This review analyses AIV diversity, evolution and the risk of AIV emergence in humans in countries of the Greater Mekong Subregion (GMS): Cambodia, Laos, Myanmar, Thailand and Vietnam (excluding China). The analysis was based on AIV sequencing data, serological studies, published journal articles and AIV outbreak reports available from January 2003 to December 2018. All countries of the GMS have suffered losses due repeated outbreaks of highly pathogenic (HP) H5N1 that has also caused human cases in all GMS countries. In Laos, Myanmar and Vietnam AIV outbreaks in domestic poultry have also been caused by clade 2.3.4.4 H5N6. A diverse range of low pathogenic AIVs (H1-H12) have been detected in poultry and wild bird species, though surveillance for and characterization of these subtypes is limited. Subtype H3, H4, H6 and H11 viruses have been detected over prolonged periods; whilst H1, H2, H7, H8, H10 and H12 viruses have only been detected transiently. H9 AIVs circulate endemically in Cambodia and Vietnam with seroprevalence data indicating human exposure to H9 AIVs in Cambodia, Thailand and Vietnam. As surveillance studies focus heavily on the detection of H5 AIVs in domestic poultry further research is needed to understand the true level of AIV diversity and the risk AIVs pose to humans in the GMS.
Collapse
Affiliation(s)
- Annika Suttie
- Virology Unit, Institute Pasteur in Cambodia, Phnom Penh, Cambodia; School of Applied and Biomedical Sciences, Federation University, Churchill, Australia; WHO Collaborating Centre for Reference and Research on Influenza, Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Erik A Karlsson
- Virology Unit, Institute Pasteur in Cambodia, Phnom Penh, Cambodia
| | - Yi-Mo Deng
- WHO Collaborating Centre for Reference and Research on Influenza, Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Aeron C Hurt
- WHO Collaborating Centre for Reference and Research on Influenza, Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Andrew R Greenhill
- School of Applied and Biomedical Sciences, Federation University, Churchill, Australia
| | - Ian G Barr
- WHO Collaborating Centre for Reference and Research on Influenza, Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Philippe Dussart
- Virology Unit, Institute Pasteur in Cambodia, Phnom Penh, Cambodia
| | - Paul F Horwood
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD 4811, Australia.
| |
Collapse
|
16
|
Elliott VL, Chheng P, Uy S, Holtgrieve GW. Monitoring of tropical freshwater fish resources for sustainable use. J Fish Biol 2019; 94:1019-1025. [PMID: 30950505 DOI: 10.1111/jfb.13974] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 03/13/2019] [Indexed: 06/09/2023]
Abstract
Tropical freshwater ecosystems are some of the world's most biodiverse and productive systems where determining what sustainable exploitation of inland fisheries looks like is particularly challenging. One of the greatest obstacles to sustainable management is collecting and using quality data on fish production and yield. The biodiversity and hydro-ecology of these systems often under open-access governance, add to the complexity of managing them. This paper describes an integrated citizen-science, earth observation, environmental DNA and independent survey approach to collecting fish and fisheries data, using the Cambodian Mekong as a case study.
Collapse
Affiliation(s)
- Vittoria L Elliott
- National Museum of Natural History, Smithsonian Institution, Northwest, Washington, USA
- Scientific Capacity Development Initiative, Biology Department, Fisheries Administration, Phnom Penh, Cambodia
| | - Phen Chheng
- Inland Fisheries Research and Development Institute, Fisheries Administration, Phnom Penh, Cambodia
| | - Sophorn Uy
- Inland Fisheries Research and Development Institute, Fisheries Administration, Phnom Penh, Cambodia
| | - Gordon W Holtgrieve
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington, USA
| |
Collapse
|
17
|
Steele JA, Richter CH, Echaubard P, Saenna P, Stout V, Sithithaworn P, Wilcox BA. Thinking beyond Opisthorchis viverrini for risk of cholangiocarcinoma in the lower Mekong region: a systematic review and meta-analysis. Infect Dis Poverty 2018; 7:44. [PMID: 29769113 DOI: 10.1186/s40249-018-0434-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 04/25/2018] [Indexed: 12/11/2022] Open
Abstract
Background Cholangiocarcinoma (CCA) is a fatal bile duct cancer associated with infection by the liver fluke, Opisthorchis viverrini, in the lower Mekong region. Numerous public health interventions have focused on reducing exposure to O. viverrini, but incidence of CCA in the region remains high. While this may indicate the inefficacy of public health interventions due to complex social and cultural factors, it may further indicate other risk factors or interactions with the parasite are important in pathogenesis of CCA. This systematic review aims to provide a comprehensive analysis of described risk factors for CCA in addition to O. viverrini to guide future integrative interventions. Main body We searched five international and seven Thai research databases to identify studies relevant to risk factors for CCA in the lower Mekong region. Selected studies were assessed for risk of bias and quality in terms of study design, population, CCA diagnostic methods, and statistical methods. The final 18 included studies reported numerous risk factors which were grouped into behaviors, socioeconomics, diet, genetics, gender, immune response, other infections, and treatment for O. viverrini. Seventeen risk factors were reported by two or more studies and were assessed with random effects models during meta-analysis. This meta-analysis indicates that the combination of alcohol and smoking (OR = 11.1, 95% CI: 5.63–21.92, P < 0.0001) is most significantly associated with increased risk for CCA and is an even greater risk factor than O. viverrini exposure. This analysis also suggests that family history of cancer, consumption of raw cyprinoid fish, consumption of high nitrate foods, and praziquantel treatment are associated with significantly increased risk. These risk factors may have complex relationships with the host, parasite, or pathogenesis of CCA, and many of these risk factors were found to interact with each other in one or more studies. Conclusions Our findings suggest that a complex variety of risk factors in addition to O. viverrini infection should be addressed in future public health interventions to reduce CCA in affected regions. In particular, smoking and alcohol use, dietary patterns, and socioeconomic factors should be considered when developing intervention programs to reduce CCA. Electronic supplementary material The online version of this article (10.1186/s40249-018-0434-3) contains supplementary material, which is available to authorized users.
Collapse
|
18
|
Patrick IW, Sovann S, Socheat S. Working towards consensus: the need for coordinated policies to assist control of foot and mouth disease and emerging disease threats in South-East Asia. REV SCI TECH OIE 2018; 36:349-358. [PMID: 28926033 DOI: 10.20506/rst.36.1.2634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Foot and mouth disease (FMD) is an important transboundary disease in South-East Asia. Its control has been a priority in the region for at least 20 years, with extensive institutional support and capacity-building being provided by the international community through the World Organisation for Animal Health. This paper describes the FMD control and eradication programme in the Mekong region (Myanmar, Thailand, the Lao People's Democratic Republic, Cambodia and Vietnam) of South-East Asia and evaluates the FMD control programme in one of the region's countries, namely Cambodia. Significant progress has been made, and the strategy for eradication is now both clearly understood and feasible in the Mekong. However, FMD control in this region requires more than just an effective vaccination strategy and regulatory support. Success will also depend on obtaining consensus and buy-in at all levels of the value chain, from input suppliers to consumers. Culturally and economically acceptable incentives must be in place to ensure that control measures are implemented, and those stakeholders who are expected to bear the risk and costs of control programmes must also be the main beneficiaries. The present institutional environment in the Mekong, and in particular in Cambodia, makes control and eradication of transboundary diseases difficult. Further work is required to ensure that control strategies are aligned with stakeholder needs and priorities, and actively improve smallholder welfare. Cattle producers and traders are crucial to the control of FMD in Cambodia. Economic incentives and education as well as regulation are required to ensure these stakeholders participate in this important transboundary disease eradication programme.
Collapse
|
19
|
Urban F, Siciliano G, Nordensvard J. China's dam-builders: their role in transboundary river management in South-East Asia. Int J Water Resour Dev 2017; 34:747-770. [PMID: 30233273 PMCID: PMC6128393 DOI: 10.1080/07900627.2017.1329138] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 05/04/2017] [Indexed: 05/06/2023]
Abstract
This article investigates China's role as the world's largest builder of and investor in large dams, focussing on the Greater Mekong Sub-Region in South-East Asia. It addresses the role Chinese actors play in dam-building as well as the environmental, social, economic and political implications by drawing on case studies from Cambodia and Vietnam. The article finds that China's dam-building is perceived very differently in different countries of South-East Asia. In Cambodia, the dams in the Greater Mekong Sub-Region are considered instruments of economic growth and development, whereas downstream in Vietnam the dams are seen as potentially undermining national growth, development and security.
Collapse
Affiliation(s)
- Frauke Urban
- Center for Development, Environment and Policy (CeDEP), SOAS, University of London, London, UK
| | - Giuseppina Siciliano
- Center for Development, Environment and Policy (CeDEP), SOAS, University of London, London, UK
| | - Johan Nordensvard
- Department of Sociology, Social Policy and Criminology, University of Southampton, Southampton, UK
| |
Collapse
|
20
|
Duc HA, Sabin LL, Cuong LQ, Thien DD, Feeley R. Potential collaboration with the private sector for the provision of ambulatory care in the Mekong region, Vietnam. Glob Health Action 2012; 5:GHA-5-10126. [PMID: 22548036 PMCID: PMC3339447 DOI: 10.3402/gha.v5i0.10126] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 02/18/2012] [Accepted: 04/04/2012] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Over the past two decades, health insurance in Vietnam has expanded nationwide. Concurrently, Vietnam's private health sector has developed rapidly and become an increasingly integral part of the health system. To date, however, little is understood regarding the potential for expanding public-private partnerships to improve health care access and outcomes in Vietnam. OBJECTIVE To explore possibilities for public-private collaboration in the provision of ambulatory care at the primary level in the Mekong region, Vietnam. DESIGN We employed a mixed methods research approach. Qualitative methods included focus group discussions with health officials and in-depth interviews with managers of private health facilities. Quantitative methods encompassed facility assessments, and exit surveys of clients at the same private facilities. RESULTS Discussions with health officials indicated generally favorable attitudes towards partnerships with private providers. Concerns were also voiced, regarding the over- and irrational use of antibiotics, and in terms of limited capacity for regulation, monitoring, and quality assurance. Private facility managers expressed a willingness to collaborate in the provision of ambulatory care, and private providers facilites were relatively well staffed and equipped. The client surveys indicated that 80% of clients first sought treatment at a private facility, even though most lived closer to a public provider. This choice was motivated mainly by perceptions of quality of care. Clients who reported seeking care at both a public and private facility were more satisfied with the latter. CONCLUSIONS Public-private collaboration in the provision of ambulatory care at the primary level in Vietnam has substantial potential for improving access to quality services. We recommend that such collaboration be explored by Vietnamese policy-makers. If implemented, we strongly urge attention to effectively managing such partnerships, establishing a quality assurance system, and strengthening regulatory mechanisms.
Collapse
Affiliation(s)
- Ha Anh Duc
- Cabinet Office, Vietnam Ministry of Health, Hanoi, Vietnam.
| | | | | | | | | |
Collapse
|