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Nakai M, Masumoto T, Asaeda T, Rahman M. Improving the efficiency of adaptive management methods in multiple fishways using environmental DNA. PLoS One 2024; 19:e0301197. [PMID: 38557776 PMCID: PMC10984549 DOI: 10.1371/journal.pone.0301197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 03/12/2024] [Indexed: 04/04/2024] Open
Abstract
Dams and weirs impede the continuity of rivers and transit of migratory fish. To overcome this obstacle, fishways are installed worldwide; however, management after installation is important. The Miyanaka Intake Dam has three fish ladders with different flow velocities and discharges and has been under adaptive management since 2012. Fish catch surveys, conducted as an adaptive management strategy, place a heavy burden on fish. Furthermore, a large number of investigators must be mobilized during the 30-day investigation period. Thus, a monitoring method using environmental DNA that exerts no burden on fish and requires only a few surveyors (to obtain water samples) and an in-house analyst was devised; however, its implementation in a fishway away from the point of analysis and with limited flow space and its effective water sampling frequency have not been reported. Therefore, in 2019, we started a trial aiming to evaluate the methods and application conditions of environmental DNA surveys for the continuous and long-term monitoring of various fish fauna upstream and downstream of the Miyanaka Intake Dam. To evaluate the fish fauna, the results of an environmental DNA survey (metabarcoding method) for 2019 to 2022 were compared to those of a catch survey in the fishway from 2012 to 2022. The results confirmed the use of environmental DNA surveys in evaluating the contribution of fishways to biodiversity under certain conditions and introduced a novel method for sample collection.
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Affiliation(s)
- Masahiko Nakai
- Japan International Consultants for Transportation Co., Ltd, Tokyo, Japan
| | - Taku Masumoto
- Energy Planning Department, East Japan Railway Company, Tokyo, Japan
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Chen W, Xiang D, Gao S, Zhu S, Wu Z, Li Y, Li J. Whole-genome resequencing confirms the genetic effects of dams on an endangered fish Hemibagrus guttatus (Siluriformes: Bagridae): A case study in a tributary of the Pearl River. Gene 2024; 895:148000. [PMID: 37979951 DOI: 10.1016/j.gene.2023.148000] [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: 09/02/2023] [Revised: 10/31/2023] [Accepted: 11/08/2023] [Indexed: 11/20/2023]
Abstract
Dam construction in riverine ecosystems has fragmented natural aquatic habitats and has altered environmental conditions. As a result, damming has been demonstrated to threaten aquatic biodiversity by reducing species distribution ranges and hindering gene exchange, leading to the inability to adapt to environmental changes. Knowledge of the contemporary genetic diversity and genetic structure of fish populations that are separated by dams is vital to developing effective conservation strategies, particularly for endangered fish species. We chose the Lianjiang River, a tributary of the Pearl River, as a case study to assess the effects of dams on the genetic diversity and genetic structure of an endangered fish species, Hemibagrus guttatus, using whole-genome resequencing data from 63 fish samples. The results indicated low levels of genetic diversity, high levels of inbreeding and decreasing trend of effective population size in fragmented H. guttatus populations. In addition, there were significant genetic structure and genetic differentiation among populations, suggesting that the dams might have affected H. guttatus populations. Our findings may benefit management and conservation practices for this endangered species that is currently suffering from the effects of dam construction.
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Affiliation(s)
- Weitao Chen
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China; Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Guangzhou 510380, China; Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and Environment, Guangzhou 510380, China
| | - Denggao Xiang
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
| | - Shang Gao
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China
| | - Shuli Zhu
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China; Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Guangzhou 510380, China; Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and Environment, Guangzhou 510380, China
| | - Zhi Wu
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China; Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Guangzhou 510380, China; Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and Environment, Guangzhou 510380, China
| | - Yuefei Li
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China; Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Guangzhou 510380, China; Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and Environment, Guangzhou 510380, China
| | - Jie Li
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, China; Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Guangzhou 510380, China; Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and Environment, Guangzhou 510380, China.
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3
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Yuan X, Wang J, He D, Lu Y, Sun J, Li Y, Guo Z, Zhang K, Li F. Influence of cascade reservoir operation in the Upper Mekong River on the general hydrological regime: A combined data-driven modeling approach. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 324:116339. [PMID: 36174472 DOI: 10.1016/j.jenvman.2022.116339] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/06/2022] [Accepted: 09/18/2022] [Indexed: 06/16/2023]
Abstract
Cross-border impact assessment of cascade reservoir operation on hydrological regimes is a vital prerequisite for the sustainable development and management of transboundary waters. However, assessment based on traditional hydrological modeling for transboundary rivers is limited by the availability of meteorological and hydrological data. In this study, a combined data-driven model (CV-LSTM) was built to simulate natural runoff without dam construction in the Upper Mekong River. Then, the simulated natural runoff was compared against the observation runoff influenced by dam operation to assess the impacts of reservoirs on flood and drought events. The research results are as follows: (1) CV-LSTM improved simulation performance by effectively utilizing spatial information from more extensive and diversified data, and it could overcome the limitation of classic data-driven models in that the spatial heterogeneity of input variables cannot be sufficiently considered. (2) Reservoir operation decreased the annual streamflow of the Upper Mekong River by 1.07% during the 2001-2016. In particular, with the operation of two mega reservoirs (Xiaowan and Nuozadu) after 2008, the annual streamflow decreased by 3.95%. (3) The upstream reservoirs exerted significant runoff regulative effects on the Lower Mekong during 2001-2016. Drought duration and severity significantly decreased at the Chiang Sean hydrological station, flood frequency decreased by 11%, and the mean day of flood occurrence decreased by 30%. This study developed an innovative approach, CV-LSTM, based on open-source spatial information, which could effectively analyze the cross-border impact of cascade reservoir operation. The results provide new insights into the quantitative assessment of the transboundary influence of upstream-downstream runoff change induced by cascade dams in international rivers.
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Affiliation(s)
- Xu Yuan
- Institute of International Rivers and Eco-security, Yunnan University, Kunming, Yunnan, 650500, China
| | - Jiahong Wang
- Institute of International Rivers and Eco-security, Yunnan University, Kunming, Yunnan, 650500, China
| | - Daming He
- Institute of International Rivers and Eco-security, Yunnan University, Kunming, Yunnan, 650500, China; Yunnan Key Laboratory of International Rivers and Transboundary Eco-security, Kunming, Yunnan, 650500, China.
| | - Ying Lu
- Institute of International Rivers and Eco-security, Yunnan University, Kunming, Yunnan, 650500, China; Yunnan Key Laboratory of International Rivers and Transboundary Eco-security, Kunming, Yunnan, 650500, China
| | - Jingrui Sun
- Institute of International Rivers and Eco-security, Yunnan University, Kunming, Yunnan, 650500, China
| | - Ya Li
- Institute of International Rivers and Eco-security, Yunnan University, Kunming, Yunnan, 650500, China
| | - Zipu Guo
- Institute of International Rivers and Eco-security, Yunnan University, Kunming, Yunnan, 650500, China
| | - Keyao Zhang
- Institute of International Rivers and Eco-security, Yunnan University, Kunming, Yunnan, 650500, China
| | - Fei Li
- School of Politics and Public Administration, Yunnan Minzu University, Kunming, Yunnan, 650504, China
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Flood-Pulse Variability and Climate Change Effects Increase Uncertainty in Fish Yields: Revisiting Narratives of Declining Fish Catches in India’s Ganga River. HYDROLOGY 2022. [DOI: 10.3390/hydrology9040053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
River-floodplains support a significant number of small-scale capture fisheries despite having undergone degradation due to human modification of river flows by dams, pollution, and climate change. River fish production is underpinned by the annual flood-pulse and associated environmental changes that act as cues for spawning and dispersal for most species. However, studies on fish stock declines have focused more on overfishing than on hydroclimatic variability. Therefore, understanding how changes in flood-pulse variability influence fishing effort and yields is critical to inform adaptive fisheries’ management. We investigated hydroclimatic factors driving flood-pulse variability and fish catch–effort dynamics in India’s Ganga River over two decades (2000–2020). We compiled fishers’ narratives of changing fish catches through semi-structured interviews to compare them with our observed trends. Flood amplitude showed increasing variability, longer duration, and earlier rise timings, linked to La Niña and El Niño phases. Catches per unit effort were correlated with total yield and effort but did not decline as fishers thought, despite overall declines in yield over time. Hydroclimatic variability was a more significant driver of changing yields than local fishing pressure. Rising uncertainty in fisheries’ production, in response to increasing flood-pulse variability and altered flows in the Gangetic Plains, may be affecting fishing behaviour and underlying resource conflicts.
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5
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Perry WB. Holding it in: yet another consequence of our fragmented rivers. JOURNAL OF FISH BIOLOGY 2022; 100:607-608. [PMID: 35332940 DOI: 10.1111/jfb.15029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 03/10/2022] [Indexed: 06/14/2023]
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Monitoring fish communities through environmental DNA metabarcoding in the fish pass system of the second largest hydropower plant in the world. Sci Rep 2021; 11:23167. [PMID: 34848787 PMCID: PMC8632987 DOI: 10.1038/s41598-021-02593-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 11/08/2021] [Indexed: 12/26/2022] Open
Abstract
The Itaipu Hydroelectric Power Plant is the second largest in the world in power generation. The artificial barrier created by its dam imposes an obstacle for fish migration. Thus, in 2002, a fish pass system, named Piracema Channel, was built to allow fish to access areas upstream of the reservoir. We tested the potential of environmental DNA metabarcoding to monitor the impact of both the dam and associated fish pass system in the Paraná River fish communities and to compare it with traditional monitoring methods. Using a fragment of the 12S gene, we characterized richness and community composition based on amplicon sequence variants, operational taxonomic units, and zero-radius OTUs. We combined GenBank and in-house data for taxonomic assignment. We found that different bioinformatics approaches showed similar results. Also, we found a decrease in fish diversity from 2019 to 2020 probably due to the recent extreme drought experienced in southeastern Brazil. The highest alpha diversity was recorded in the mouth of the fish pass system, located in a protected valley with the highest environmental heterogeneity. Despite the clear indication that the reference databases need to be continuously improved, our results demonstrate the analytical efficiency of the metabarcoding to monitor fish species.
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7
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Chen W, Zhu S, Yang J, Li X, Li Y, Li J. DNA barcoding reveals the temporal community composition of drifting fish eggs in the lower Hongshui River, China. Ecol Evol 2021; 11:11507-11514. [PMID: 34429936 PMCID: PMC8366882 DOI: 10.1002/ece3.7943] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 07/05/2021] [Accepted: 07/09/2021] [Indexed: 11/08/2022] Open
Abstract
Determining the temporal community composition of fish eggs in particular regions and understanding the reproductive times of regional fish taxa are key aspects of the management and regulation of regional fish stocks. However, it is extremely difficult to accurately identify fish eggs due to the absence of diagnostic morphological characters. We sampled fish eggs in the lower Hongshuihe River (an upper mainstem of the Pearl River) between May and September 2020. We then used DNA barcoding to determine the species composition of the egg pool and to predict the spawning periods of the identified species. A total of 641 eggs and 17 larvae were chosen for molecular identification; 397 eggs and 17 larvae yielded high-quality barcoding sequences. The high failure rate (~38%) was most likely due to long-term storage in low concentrations of ethanol prior to molecular analysis. We successfully classified 392 eggs into 10 species and 13 larvae into four species using public databases. Most of the species identified in the egg pool were small and/or benthic, and migratory species were rare. This may partially reflect the adverse effects of hydropower cascade development in this river section. We also found that spawning periods tended to be species-specific. Our study provides a reference for the conservation and management of regional fishery stocks.
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Affiliation(s)
- Weitao Chen
- Pearl River Fisheries Research InstituteChinese Academy of Fishery ScienceGuangzhouChina
- Key Laboratory of Aquatic Animal Immune Technology of Guangdong ProvinceGuangzhouChina
- Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and EnvironmentGuangzhouChina
- Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl RiverZhaoqingChina
| | - Shuli Zhu
- Pearl River Fisheries Research InstituteChinese Academy of Fishery ScienceGuangzhouChina
- Key Laboratory of Aquatic Animal Immune Technology of Guangdong ProvinceGuangzhouChina
- Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and EnvironmentGuangzhouChina
- Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl RiverZhaoqingChina
| | - Jiping Yang
- Pearl River Fisheries Research InstituteChinese Academy of Fishery ScienceGuangzhouChina
- Key Laboratory of Aquatic Animal Immune Technology of Guangdong ProvinceGuangzhouChina
- Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and EnvironmentGuangzhouChina
- Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl RiverZhaoqingChina
| | - Xinhui Li
- Pearl River Fisheries Research InstituteChinese Academy of Fishery ScienceGuangzhouChina
- Key Laboratory of Aquatic Animal Immune Technology of Guangdong ProvinceGuangzhouChina
- Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and EnvironmentGuangzhouChina
- Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl RiverZhaoqingChina
| | - Yuefei Li
- Pearl River Fisheries Research InstituteChinese Academy of Fishery ScienceGuangzhouChina
- Key Laboratory of Aquatic Animal Immune Technology of Guangdong ProvinceGuangzhouChina
- Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and EnvironmentGuangzhouChina
- Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl RiverZhaoqingChina
| | - Jie Li
- Pearl River Fisheries Research InstituteChinese Academy of Fishery ScienceGuangzhouChina
- Key Laboratory of Aquatic Animal Immune Technology of Guangdong ProvinceGuangzhouChina
- Guangzhou Scientific Observing and Experimental Station of National Fisheries Resources and EnvironmentGuangzhouChina
- Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl RiverZhaoqingChina
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8
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Investigating the trophic ecology of freshwater fish communities from central and eastern Indian streams using stable isotope analysis. COMMUNITY ECOL 2021. [DOI: 10.1007/s42974-021-00049-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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9
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DNA barcoding for identification of fishes in Xiangjiaba reservoir area in the downstream section of the Jinsha river. CONSERV GENET RESOUR 2021. [DOI: 10.1007/s12686-021-01196-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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10
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Molecular identification and temporal genetic differentiation of Cyprinus carpio (Cypriniformes: Cyprinidae) eggs attached on artificial fish nests. CONSERV GENET RESOUR 2021. [DOI: 10.1007/s12686-021-01189-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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11
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Chen W, Li C, Yang J, Zhu S, Li J, Li Y, Li X. Temporal species-level composition of larvae resources in the lower Pearl River drainage and implications for species' reproductive cycles. Gene 2020; 776:145351. [PMID: 33333226 DOI: 10.1016/j.gene.2020.145351] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 11/04/2020] [Accepted: 12/01/2020] [Indexed: 11/30/2022]
Abstract
Resolving the temporal community composition of a larvae population can not only further our understanding of the regional species composition but also help us to infer the reproductive times of regional fish taxa, which can have implications on the development of effective monitoring and conservation policies for the regional fish stock. Nevertheless, correctly diagnosing the fish larvae is extremely challenging due to the paucity of diagnostic morphological characters at the species level. Based on daily larval samplings during March and October in 2018, this study combined morphological features with a DNA barcode technique to determine the species composition of fish larvae in the lower Pearl River drainage (LPR) and evaluate the spawning periods of identified species. Due to an absence of reference barcodes for LPR fishes, a DNA barcode library of adult fishes in the LPR was built for 384 individuals representing 78 morphological species. Analyses demonstrated the usability of the barcode library and uncovered many undetected mitochondrial lineages in 12 species. Morphological analyses performed on 81 temporal larval samples revealed 25 morphotypes and assigned 9 morphotypes into the species level. A total of 1624 larvae from 96 temporal larval samples were selected for molecular identification, and high quality barcoding sequences were obtained from 1391 larvae. We accurately assigned 1078 larvae to 37 species using our barcode library and published database. Among the identified species, a critically endangered species, namely, Ochetobius elongatus, and several invasive species were examined, providing a new perspective to assess the stock of regional endangered and invasive species. Furthermore, this study found high species diversity occurred primarily between May and September, and clarified the spawning periods of identified species inferred from the temporal occurrences of larvae. Above all, our study highlights the applicability to fish larval ecology to assist conservation and fishery management efforts.
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Affiliation(s)
- Weitao Chen
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou, China; Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl River, Zhaoqing, China
| | - Ce Li
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou, China
| | - Jiping Yang
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou, China; Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl River, Zhaoqing, China
| | - Shuli Zhu
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou, China; Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl River, Zhaoqing, China
| | - Jie Li
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou, China; Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl River, Zhaoqing, China
| | - Yuefei Li
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou, China; Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl River, Zhaoqing, China.
| | - Xinhui Li
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou, China; Experimental Station for Scientific Observation on Fishery Resources and Environment in the Middle and Lower Reaches of Pearl River, Zhaoqing, China.
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12
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Chea R, Pool TK, Chevalier M, Ngor P, So N, Winemiller KO, Lek S, Grenouillet G. Impact of seasonal hydrological variation on tropical fish assemblages: abrupt shift following an extreme flood event. Ecosphere 2020. [DOI: 10.1002/ecs2.3303] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Ratha Chea
- Laboratory of Freshwater Ecology Graduate School University of Battambang Battambang Cambodia
- Laboratoire Evolution & Diversité Biologique (EDB UMR5174) Université de Toulouse, CNRS, IRD, UPS Toulouse Cedex France
| | - Thomas K. Pool
- School of Aquatic and Fishery Sciences (SAFS) University of Washington Seattle Washington98195USA
| | - Mathieu Chevalier
- Laboratoire Evolution & Diversité Biologique (EDB UMR5174) Université de Toulouse, CNRS, IRD, UPS Toulouse Cedex France
| | - Pengbun Ngor
- Fisheries Administration Inland Fisheries Research and Development Institute (IFREDI) Phnom Penh Cambodia
| | - Nam So
- Fisheries Administration Inland Fisheries Research and Development Institute (IFREDI) Phnom Penh Cambodia
- Mekong River Commission Secretariat (MRCS) Vientiane Lao PDR
| | - Kirk O. Winemiller
- Department Wildlife and Fisheries Sciences Texas A&M University College Station Texas77843USA
| | - Sovan Lek
- Laboratoire Evolution & Diversité Biologique (EDB UMR5174) Université de Toulouse, CNRS, IRD, UPS Toulouse Cedex France
| | - Gaël Grenouillet
- Laboratoire Evolution & Diversité Biologique (EDB UMR5174) Université de Toulouse, CNRS, IRD, UPS Toulouse Cedex France
- Institut Universitaire de France Paris France
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13
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Fish Biodiversity Conservation and Restoration, Yangtze River Basin, China, Urgently Needs ‘Scientific’ and ‘Ecological’ Action. WATER 2020. [DOI: 10.3390/w12113043] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Although many significant policies and legislation have been put forth by the Chinese government aiming toward “ecological civilization” for the aquatic environment, in practice, the situation is still undesirable. A pioneering multi-year study has since been conducted on the East Tiaoxi River (a major tributary of the renowned Yangtze River), focusing on fish distribution, influencing factors and habitat requirements, and river health as well. This revealed certain key species, hotspot protection areas, negative impacts of local anthropogenic activities, and inappropriate perceptions and practices of conservation and restoration. We found that not all fish species were equally conserved and that the supposedly ecological engineering measures were initiated without regard for ecological integrity. Our exemplary study appreciates scientific basis and truly ecological notion, and urgently advocates comprehensive and continuous basin-scale scientific investigation of fish biodiversity, and “ecological river”-oriented conservation and restoration action for the Yangtze River Basin and broader areas of China.
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14
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Jiang Z, Dai B, Wang C, Xiong W. Multifaceted biodiversity measurements reveal incongruent conservation priorities for rivers in the upper reach and lakes in the middle-lower reach of the largest river-floodplain ecosystem in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 739:140380. [PMID: 32758978 DOI: 10.1016/j.scitotenv.2020.140380] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 06/07/2020] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
Biological conservation necessitates robust understanding of multifaceted biodiversity from local to regional scales. Mismatches among multifaceted diversity and conservation trade-offs are the most important challenge for conservation planning. The Yangtze River floodplain is among the most speciose whereas threatened and poorly protected ecosystems in China. Here we evaluated multifaceted (taxonomic, phylogenetic, and functional) alpha and beta fish diversity by simultaneously addressing two typical habitats (FRs, floodplain rivers and FLs, floodplain lakes) in this basin, to reliably aid conservation planning across local and regional scales. Our results demonstrated spatially incongruent multifaceted fish diversity between FRs and FLs. Characterizing by flocks of phylogenetic close species, we detected significantly higher species richness while lower phylogenetic and functional alpha diversity in FRs. In contrast, fish assemblages in FLs exhibited significantly higher functional alpha diversity characterized by functional unique species. Consequently, conservation planning should fasten on clusters of phylogenetic close endemic species to sustain high intrinsic species richness in FRs, and sustain high functional diversity as well as protecting fish species with unique functions in FLs. Meanwhile, for all the taxonomic, phylogenetic, and functional facets, our results demonstrated significantly higher turnover components in FRs, and the dominant contribution of the nestedness components to overall beta diversity in FLs. As a result, conservation planning in FLs may just focus on several richest lakes, while multiple spatially disjunct river networks should be protected in FRs. Contradicting the anthropocentric "new conservation", our study advocated protecting intrinsic uniqueness and peculiarity of multifaceted biodiversity as well as the ecological integrity.
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Affiliation(s)
- Zhongguan Jiang
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, PR China; Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration, Hefei 230601, PR China
| | - Bingguo Dai
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, PR China; Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration, Hefei 230601, PR China.
| | - Chao Wang
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, PR China
| | - Wen Xiong
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524088, PR China
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15
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Mondal R, Bhat A. Temporal and environmental drivers of fish-community structure in tropical streams from two contrasting regions in India. PLoS One 2020; 15:e0227354. [PMID: 32271767 PMCID: PMC7145018 DOI: 10.1371/journal.pone.0227354] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 12/17/2019] [Indexed: 11/18/2022] Open
Abstract
Environmental and anthropogenic factors are known to drive fish community structure in aquatic systems across the world. This study investigates fish assemblages in lower order streams across contrasting landscapes in central and eastern India. We documented the species diversity of these monsoon driven lower order streams in the two regions. We also investigated the potential common environmental drivers of richness and diversity and effect of season in these tropical streams. The study was based on seasonal data on abundance of fishes and environmental parameters collected between 2015–2017 from streams in states of Madhya Pradesh and West Bengal. Species diversity were compared across regions and seasons, based on their richness (SR) as well as diversity (Shannon index H'). Drivers of overall richness and diversity were analyzed using multiple linear regression methods, based on best subset selection. Analysis of data revealed high diversity in these streams in both regions. Cyprinidae, Bagridae and Channidae were the most dominant families in both regions. Despite the geographical and local ecological differences across the regions, common environmental parameters were found to influence richness and diversity across the two regions, indicating these as being key drivers of fish community structure. Water flow was a common factor driving both richness and diversity across both regions. Our study revealed a lack of seasonal effect in structuring fish communities in tropical streams. With stream and river ecosystems facing increasing threats due to habitat alterations and water quality degradation in countries such as India, a clear understanding of regional and local drivers of community structure of aquatic fauna is crucial. These results on the role of common environmental factors across ecoregions provides baseline information for understanding their ecological roles and developing management plans for important river basins and fish conservation in future.
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Affiliation(s)
- Rubina Mondal
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India
| | - Anuradha Bhat
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India
- * E-mail:
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16
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A Cone Fishway Facilitates Lateral Migrations of Tropical River-Floodplain Fish Communities. WATER 2020. [DOI: 10.3390/w12020513] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Fisheries in many tropical river-floodplain systems are under threat from physical obstructions caused by ongoing river infrastructure development. There is a growing need for innovative, cost-effective technologies to mitigate the impacts of these obstructions. This study examined the effectiveness of a new cone fishway for facilitating lateral migrations of river-floodplain fish communities in the Lower Mekong Basin in Lao PDR. We assessed the species richness, size range, abundance and biomass of fish able to pass through a cone fishway, using paired entrance and exit sampling during both dawn/day and dusk/night. Overall, a diverse range of taxa (76 species) and size classes (25–370 mm) ascended the cone fishway. The total size range of fishes observed at the fishway entrance was similar to that at the exit, although the fish at the entrance were significantly smaller (in length) than those at the exit, during both diel periods. Additionally, there were significantly higher abundances of fish at the entrance than at the exit, but there was no difference in total biomass, again for both periods. These results suggest that, with further development, the cone fishway design has considerable potential for facilitating the lateral migrations of diverse tropical river-floodplain fish communities at low/medium head infrastructure.
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Wei L, Ye X, Lv Y, Teng Z, Gan B, Zou H, Mo F, Zhang S. Complete mitochondrial genome and phylogenetic position of Pangasius sanitwongsei (Siluriformes: Pangasiidae). MITOCHONDRIAL DNA PART B-RESOURCES 2020; 5:945-946. [PMID: 33366819 PMCID: PMC7748851 DOI: 10.1080/23802359.2020.1719915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In this study, the complete mitochondrial genome of Pangasius sanitwongsei was firstly reported and analyzed. It had a double-stand DNA molecule with 16536 bp in length, consisting of 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and one control region. The structural organization and gene order was similar to other bony fishes. The complete mitochondrial genome of P. sanitwongsei provided in this work would be helpful for further research on phylogenetics and conservation genetics of the Siluriformes and other orders.
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Affiliation(s)
- Lingjing Wei
- Aquatic Species Introduction and Breeding Center of Guangxi, Nanning, China
| | - Xiangchen Ye
- Aquatic Species Introduction and Breeding Center of Guangxi, Nanning, China
| | - Yejian Lv
- Aquatic Species Introduction and Breeding Center of Guangxi, Nanning, China
| | - Zhongzuo Teng
- Aquatic Species Introduction and Breeding Center of Guangxi, Nanning, China
| | - Baojiang Gan
- Aquatic Species Introduction and Breeding Center of Guangxi, Nanning, China
| | - Hui Zou
- Aquatic Species Introduction and Breeding Center of Guangxi, Nanning, China
| | - Feilong Mo
- Aquatic Species Introduction and Breeding Center of Guangxi, Nanning, China
| | - Sheng Zhang
- Aquatic Species Introduction and Breeding Center of Guangxi, Nanning, China
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18
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Lintermans M, Geyle HM, Beatty S, Brown C, Ebner BC, Freeman R, Hammer MP, Humphreys WF, Kennard MJ, Kern P, Martin K, Morgan DL, Raadik TA, Unmack PJ, Wager R, Woinarski JCZ, Garnett ST. Big trouble for little fish: identifying Australian freshwater fishes in imminent risk of extinction. ACTA ACUST UNITED AC 2020. [DOI: 10.1071/pc19053] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Globally, freshwater fishes are declining at an alarming rate. Despite much evidence of catastrophic declines, few Australian species are listed as threatened under national legislation. We aim to help redress this by identifying the Australian freshwater fishes that are in the most immediate risk of extinction. For 22 freshwater fishes (identified as highly threatened by experts), we used structured expert elicitation to estimate the probability of extinction in the next ~20 years, and to identify key threats and priority management needs. All but one of the 22 species are small (<150mm total length), 12 have been formally described only in the last decade, with seven awaiting description. Over 90% of these species were assessed to have a >50% probability of extinction in the next ~20 years. Collectively, the biggest factor contributing to the likelihood of extinction of the freshwater fishes considered is that they occur in small (distributions ≤44km2), geographically isolated populations, and are threatened by a mix of processes (particularly alien fishes and climate change). Nineteen of these species are unlisted on national legislation, so legislative drivers for recovery actions are largely absent. Research has provided strong direction on how to manage ~35% of known threats to the species considered, and, of these, ~36% of threats have some management underway (although virtually none are at the stage where intervention is no longer required). Increased resourcing, management intervention and social attitudinal change is urgently needed to avert the impending extinction of Australia’s most imperilled freshwater fishes.
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Zhai DD, Li WJ, Liu HZ, Cao WX, Gao X. Genetic diversity and temporal changes of an endemic cyprinid fish species, Ancherythroculter nigrocauda, from the upper reaches of Yangtze River. Zool Res 2019; 40:427-438. [PMID: 31111694 PMCID: PMC6755114 DOI: 10.24272/j.issn.2095-8137.2019.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Accepted: 04/16/2019] [Indexed: 11/07/2022] Open
Abstract
Small populations with low genetic diversity are prone to extinction. Knowledge on the genetic diversity and structure of small populations and their genetic response to anthropogenic effects are of critical importance for conservation management. In this study, samples of Ancherythroculter nigrocauda, an endemic cyprinid fish from the upper reaches of Yangtze River, were collected from five sites to analyze their genetic diversity and population structure using mitochondrial cytochrome b gene and 14 microsatellite loci. Haplotype diversity, nucleotide diversity, and expected heterozygosity indicated that the A. nigrocauda populations had low genetic diversity, and decreased heavily from 2001 to 2016. Significant genetic differentiation was found among different populations in the cyt b gene and SSR markers based on the genetic differentiation index (F ST), whereas no differentiation was found in 2001. Haplotype genealogy showed that eight out of 15 haplotypes were private to one population. The SSR STRUCTURE analysis showed that there were four genetic clusters in the A. nigrocauda samples, with each population forming a single cluster, except for the Chishui River (CSR) and Mudong River (MDR) populations, which formed a common cluster. Therefore, loss of genetic diversity and increased genetic differentiation were found in the A. nigrocauda populations, which could be attributed to dam construction, overfishing, and water pollution in the upper Yangtze River. It is therefore recommended that the government should ban fishing, control water pollution, increase river connectivity, and establish artificial breeding and stocking.
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Affiliation(s)
- Dong-Dong Zhai
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan Hubei 430072, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wen-Jing Li
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan Hubei 430072, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Huan-Zhang Liu
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan Hubei 430072, China
| | - Wen-Xuan Cao
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan Hubei 430072, China
| | - Xin Gao
- Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan Hubei 430072, China; E-mail:
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20
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Hu M, Wang C, Liu Y, Zhang X, Jian S. Fish species composition, distribution and community structure in the lower reaches of Ganjiang River, Jiangxi, China. Sci Rep 2019; 9:10100. [PMID: 31300743 PMCID: PMC6626018 DOI: 10.1038/s41598-019-46600-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 06/07/2019] [Indexed: 11/09/2022] Open
Abstract
The Ganjiang River (length: 823 km; drainage area: 82,809 km2) is the largest river that flows into Poyang Lake and an important tributary of the Yangtze River. In this study, fish fauna were collected from 10 stations in the lower reaches of the river (YC: Yichun, XY: Xinyu, SG: Shanggao, GA: Ganan, ZS: Zhangshu, FC: Fengcheng, NC: Nanchang, QS: Qiaoshe, NX: Nanxin, CC: Chucha) from March 2017 to February 2018. The species composition and distribution as well as spatio-temporal variation in biodiversity and abundance were then examined. Overall, 12,680 samples comprising15 families and 84 species were collected, the majority of which belonged to the Order Cypriniformes (69.05% of the total species collected) and Cyprinidae (64.29%). Moreover, of these 84 species, 36 (42.86%) were endemic to China. Dominant species were Cyprinus carpio (index of relative importance (IRI): 17.19%), Pseudobrama simoni (IRI: 10.81%) and Xenocypris argentea (IRI: 10.20%). Subsequent cluster analysis divided the samples into three significantly different groups by sample site. Meanwhile, Margalef species richness and Shannon-Wiener diversity indices were both low, and along with analyses of abundance-biomass curves suggested moderate disturbance. Current threats to the conservation of fish biodiversity in the lower reaches were also reviewed and management solutions suggested. The results will help form the basis for reasonable exploitation and protection of freshwater fish in the lower reaches of the Ganjiang River.
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Affiliation(s)
- Maolin Hu
- School of Life Sciences, Nanchang University, Nanchang, Jiangxi, 330031, P. R. China.
- Ministry of Education Key Laboratory of Poyang Lake Environment and Resource Utilization, Nanchang University, Nanchang, Jiangxi, 330031, P. R. China.
- Jiangxi Key Laboratory of Aquatic Animal Resource and Utilization, Nanchang University, Nanchang, Jiangxi, 330031, P. R. China.
| | - Chaoyang Wang
- School of Life Sciences, Nanchang University, Nanchang, Jiangxi, 330031, P. R. China
| | - Yizhen Liu
- School of Life Sciences, Nanchang University, Nanchang, Jiangxi, 330031, P. R. China
- Ministry of Education Key Laboratory of Poyang Lake Environment and Resource Utilization, Nanchang University, Nanchang, Jiangxi, 330031, P. R. China
| | - Xiangyu Zhang
- School of Life Sciences, Nanchang University, Nanchang, Jiangxi, 330031, P. R. China
| | - Shaoqing Jian
- School of Life Sciences, Nanchang University, Nanchang, Jiangxi, 330031, P. R. China
- Jiangxi Key Laboratory of Aquatic Animal Resource and Utilization, Nanchang University, Nanchang, Jiangxi, 330031, P. R. China
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21
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Guo XZ, Zhang GR, Wei KJ, Ji W, Yan RJ, Wei QW, Gardner JPA. Phylogeography of the threatened tetraploid fish, Schizothorax waltoni, in the Yarlung Tsangpo River on the southern Qinghai-Tibet Plateau: implications for conservation. Sci Rep 2019; 9:2704. [PMID: 30804376 PMCID: PMC6390103 DOI: 10.1038/s41598-019-39128-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 01/17/2019] [Indexed: 11/09/2022] Open
Abstract
The phylogeography of Schizothorax waltoni, an endemic and endangered tetraploid schizothoracine fish in the Yarlung Tsangpo River (YLTR) on southern margin of Qinghai-Tibet Plateau (QTP), was investigated using two mitochondrial DNA regions and eleven microsatellite loci. Analyses of concatenated sequences of cytochrome b (1141 bp) and the control region (712 bp) revealed high haplotype diversity and moderate nucleotide diversity. High genetic diversity was observed based on microsatellite variation. Both mtDNA and microsatellite analyses revealed significant genetic differentiation between the eastern population (Mainling) and the other four populations to the west, and non-significant genetic differentiation amongst the three central populations in the west. Significant genetic differentiation was observed between the western population (Shigatse) and the three central populations based on microsatellite analyses alone. Bayesian skyline plot analyses showed that S. waltoni experienced a pronounced population expansion 0.05 to 0.10 Ma. Hierarchical structure analyses of microsatellite data indicated that S. waltoni could be split into three groups (western, central and eastern YLTR). The results indicate that three management units should be considered for S. waltoni. Our findings highlight the need for the conservation and effective management of S. waltoni, which is a key member of the endemic and highly threatened fishes of the QTP.
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Affiliation(s)
- Xiang-Zhao Guo
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, P. R. China.,Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, P. R. China.,Guangdong Haid Group Co., Ltd., Guangzhou, 511400, P. R. China
| | - Gui-Rong Zhang
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, P. R. China.,Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, P. R. China
| | - Kai-Jian Wei
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, P. R. China. .,Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, P. R. China.
| | - Wei Ji
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, P. R. China.,Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, P. R. China
| | - Ruo-Jin Yan
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, P. R. China.,Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, P. R. China.,School of Biological Sciences, Victoria University of Wellington, P O Box 600, Wellington, 6140, New Zealand
| | - Qi-Wei Wei
- Key Laboratory of Freshwater Biodiversity Conservation, Ministry of Agriculture, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, 430223, P. R. China
| | - Jonathan P A Gardner
- Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, P. R. China.,Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan, 430070, P. R. China.,School of Biological Sciences, Victoria University of Wellington, P O Box 600, Wellington, 6140, New Zealand
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22
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Andrés-Costa MJ, Pascual-Aguilar J, Andreu V, Picó Y. Assessing drugs of abuse distribution in Turia River based on geographic information system and liquid chromatography mass spectrometry. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 609:360-369. [PMID: 28753511 DOI: 10.1016/j.scitotenv.2017.07.123] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 06/23/2017] [Accepted: 07/13/2017] [Indexed: 06/07/2023]
Abstract
Drugs of abuse are continuously discharged into wastewaters as part of their elimination process. Pollution at very low concentrations appears to be broad in environmental compartments near populated areas. A total of 42 drugs of abuse and metabolites were analysed in surface water samples collected in 2012 and 2013 by solid phase extraction and liquid chromatography coupled to mass spectrometry. Analytical results of target compounds were georeferenced and integrated into a geographical information systems (GIS). Ecotoxicological risk of drugs of abuse detected in the Turia River was evaluated in this study by calculating risk quotient (RQ). In 2012, 6 compounds were detected in a total of 22 points. In 2013, 7 compounds were found in a total of 31 sampling sites, 4 of them also detected in 2012. The most frequent compound was benzoylecgonine, detected in 9 sampling points in 2012 and 8 in 2013, at an average concentration of 25.4ng/L and 14.02ng/L. Codeine reached the maximum concentration of detected compounds (101ng/L) in 2013. GIS provided the spatial incidence of drugs of abuse along the Turia River basin. The distribution of these compounds in 2012 and 2013 shows that the highest concentrations and frequency of drugs of abuse run into places with the highest population density. The RQ obtained from measured concentrations of detected drugs predict that no short-term environmental risk might be expected. Further research including multi-stressors studies with more potentially persistent or pseudo-persistent organic pollutants in surface waters is needed to establish relationships with human pressure in a river basin.
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Affiliation(s)
- María Jesús Andrés-Costa
- Environmental and Food Safety Research Group (SAMA-UV), Desertification Research Centre CIDE (CSIC-UV-GV), Faculty of Pharmacy, University of Valencia, Av. Vicent Andrés Estellés s/n, Burjassot, 46100, Valencia, Spain.
| | - Juan Pascual-Aguilar
- Lanscape Chemistry and Environmental Forensics Group, CIDE (CSIC-UV-GV), Carretera Moncada, Náquera, Km. 4.5, Moncada, 46113, Valencia, Spain
| | - Vicente Andreu
- Lanscape Chemistry and Environmental Forensics Group, CIDE (CSIC-UV-GV), Carretera Moncada, Náquera, Km. 4.5, Moncada, 46113, Valencia, Spain
| | - Yolanda Picó
- Environmental and Food Safety Research Group (SAMA-UV), Desertification Research Centre CIDE (CSIC-UV-GV), Faculty of Pharmacy, University of Valencia, Av. Vicent Andrés Estellés s/n, Burjassot, 46100, Valencia, Spain
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23
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Gibson L, Wilman EN, Laurance WF. How Green is 'Green' Energy? Trends Ecol Evol 2017; 32:922-935. [PMID: 29074270 DOI: 10.1016/j.tree.2017.09.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 09/20/2017] [Accepted: 09/21/2017] [Indexed: 10/18/2022]
Abstract
Renewable energy is an important piece of the puzzle in meeting growing energy demands and mitigating climate change, but the potentially adverse effects of such technologies are often overlooked. Given that climate and ecology are inextricably linked, assessing the effects of energy technologies requires one to consider their full suite of global environmental concerns. We review here the ecological impacts of three major types of renewable energy - hydro, solar, and wind energy - and highlight some strategies for mitigating their negative effects. All three types can have significant environmental consequences in certain contexts. Wind power has the fewest and most easily mitigated impacts; solar energy is comparably benign if designed and managed carefully. Hydropower clearly has the greatest risks, particularly in certain ecological and geographical settings. More research is needed to assess the environmental impacts of these 'green' energy technologies, given that all are rapidly expanding globally.
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Affiliation(s)
- Luke Gibson
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China.
| | - Elspeth N Wilman
- School of Biological Sciences, University of Hong Kong, Hong Kong, China
| | - William F Laurance
- Centre for Tropical Environmental and Sustainability Science, and College of Science and Engineering, James Cook University, Cairns, Queensland 4878, Australia
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24
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Chen W, Zhong Z, Dai W, Fan Q, He S. Phylogeographic structure, cryptic speciation and demographic history of the sharpbelly (Hemiculter leucisculus), a freshwater habitat generalist from southern China. BMC Evol Biol 2017; 17:216. [PMID: 28899345 PMCID: PMC5596851 DOI: 10.1186/s12862-017-1058-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 08/30/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Species with broad distributions frequently divide into multiple genetic forms and may therefore be viewed as "cryptic species". Here, we used the mitochondrial cytochrome b (Cytb) and 12 nuclear DNA loci to investigate phylogeographic structures of the sharpbelly (Hemiculter leucisculus) in rivers in southern China and explored how the geological and climatic factors have shaped the genetic diversity and evolutionary history of this species. RESULTS Our mitochondrial phylogenetic analysis identified three major lineages (lineages A, B, and C). Lineages B and C showed a relatively narrower geographic distribution, whereas lineage A was widely distributed in numerous drainages. Divergence dates suggested that H. leucisculus populations diverged between 1.61-2.38 Ma. Bayesian species delimitation analysis using 12 nuclear DNA loci indicated the three lineages probably represented three valid taxa. Isolation-with-migration (IM) analysis found substantial gene flow has occurred among the three lineages. Demographic analyses showed that lineages B and C have experienced rapid demographic expansion at 0.03 Ma and 0.08 Ma, respectively. CONCLUSIONS Hemiculter leucisculus populations in drainages in southern China comprise three mtDNA lineages, and each of which may represent a separate species. Intense uplift of the Qinghai-Tibetan Plateau, evolution of Asian monsoons, changes in paleo-drainages, and poor dispersal ability may have driven the divergence of the three putative species. However, gene flow occurs among the three lineages. Climatic fluctuations have a prominent impact on the populations from the lineages B and C, but exerted little influence on the lineage A.
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Affiliation(s)
- Weitao Chen
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China.,University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Zaixuan Zhong
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China.,University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Wei Dai
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China.,University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Qi Fan
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China
| | - Shunping He
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China.
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25
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Using local ecological knowledge to monitor threatened Mekong megafauna in Lao PDR. PLoS One 2017; 12:e0183247. [PMID: 28820901 PMCID: PMC5562319 DOI: 10.1371/journal.pone.0183247] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 08/01/2017] [Indexed: 11/19/2022] Open
Abstract
Pressures on freshwater biodiversity in Southeast Asia are accelerating yet the status and conservation needs of many of the region’s threatened fish species are unclear. This impacts the ability to implement conservation activities and to understand the effects of infrastructure developments and other hydrological changes. We used Local Ecological Knowledge from fishing communities on the Mekong River in the Siphandone waterscape, Lao PDR to estimate mean and mode last capture dates of eight rare or culturally significant fish species in order to provide conservation monitoring baselines. One hundred and twenty fishermen, from six villages, were interviewed. All eight species had been captured, by at least one of the interviewees, within the waterscape within the past year. However the mean and mode last capture dates varied between the species. Larger species, and those with higher Red List threat status, were caught less recently than smaller species of less conservation concern. The status of the Critically Endangered Pangasius sanitwongsei (mean last capture date 116.4 months) is particularly worrying suggesting severe population decline although cultural issues may have caused this species to have been under-reported. This highlights that studies making use of Local Ecological Knowledge need to understand the cultural background and context from which data is collected. Nevertheless we recommend our approach, of stratified random interviews to establish mean last capture dates, may be an effective methodology for monitoring freshwater fish species of conservation concern within artisanal fisheries. If fishing effort remains relatively constant, or if changes in fishing effort are accounted for, differences over time in mean last capture dates are likely to represent changes in the status of species. We plan to repeat our interview surveys within the waterscape as part of a long-term fish-monitoring program.
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26
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Elmer LK, Kelly LA, Rivest S, Steell SC, Twardek WM, Danylchuk AJ, Arlinghaus R, Bennett JR, Cooke SJ. Angling into the Future: Ten Commandments for Recreational Fisheries Science, Management, and Stewardship in a Good Anthropocene. ENVIRONMENTAL MANAGEMENT 2017; 60:165-175. [PMID: 28600638 DOI: 10.1007/s00267-017-0895-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 05/23/2017] [Indexed: 05/24/2023]
Abstract
A new geological epoch, the "Anthropocene", has been defined as the period in which humans have had substantial geological and ecological influence on the planet. A positive future for this epoch can be referred to as the "good Anthropocene" and would involve effective management strategies and changes in human behavior that promote the sustainability and restoration of ecosystems. Recreational fisheries hold significant social, cultural, and economic value and can generate many benefits when managed sustainably and thus be an integral part of a "good Anthropocene". Here, we list ten commandments to facilitate persistence and long-term sustainability of recreational fisheries in the "good Anthropocene". This list includes fostering aquatic stewardship, promoting education, using appropriate capture gear, adopting evidence-based management approaches, promoting the concept of resilience, obtaining and using effort data in management, embracing the ecosystem approach, engaging in multilevel collaboration, enhancing accessibility, and embracing optimism. When used singly, or simultaneously, these ten commandments will contribute to the harmonization of sustainable fish populations and angling practices, to create recreational fisheries' "bright spots".
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Affiliation(s)
- Laura K Elmer
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental Science, Carleton University, Ottawa, ON, Canada.
| | - Lisa A Kelly
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental Science, Carleton University, Ottawa, ON, Canada
| | - Stephanie Rivest
- Department of Biology, University of Ottawa, 75 Laurier Ave E, Ottawa, ON, Canada
| | - S Clay Steell
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental Science, Carleton University, Ottawa, ON, Canada
| | - William M Twardek
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental Science, Carleton University, Ottawa, ON, Canada
| | - Andy J Danylchuk
- Department of Environmental Conservation, University of Massachusetts Amherst, Amherst, MA, USA
| | - Robert Arlinghaus
- Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries & Division of Integrative Fisheries Management, Faculty of Life Sciences & Integrative Research Institute on Transformation of Human-Environment Systems, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Joseph R Bennett
- Institute of Environmental Science and Department of Biology, Carleton University, Ottawa, ON, Canada
| | - Steven J Cooke
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental Science, Carleton University, Ottawa, ON, Canada
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27
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Chen Y, Zhang S, Huang D, Li BL, Liu J, Liu W, Ma J, Wang F, Wang Y, Wu S, Wu Y, Yan J, Guo C, Xin W, Wang H. The development of China's Yangtze River Economic Belt: how to make it in a green way? Sci Bull (Beijing) 2017; 62:648-651. [PMID: 36659306 DOI: 10.1016/j.scib.2017.04.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 04/14/2017] [Accepted: 04/14/2017] [Indexed: 01/21/2023]
Affiliation(s)
- Yushun Chen
- Institute of Hydrobiology & State Key Laboratory of Freshwater Ecology and Biotechnology, Chinese Academy of Sciences, Wuhan 430072, China.
| | - Shuanghu Zhang
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Desheng Huang
- Policy Research Center for Environment and Economy, Ministry of Environmental Protection of P.R. China, Beijing 100029, China
| | - Bai-Lian Li
- Ecological Complexity and Modeling Laboratory, University of California, Riverside, CA 92521-0124, USA
| | - Junguo Liu
- School of Environmental Science and Engineering, Southern University of Science and Technology of China, Shenzhen 518055, China
| | - Wenjin Liu
- Orient Landscape Industry Group Ltd., Beijing 100015, China
| | - Jing Ma
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Fang Wang
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Yong Wang
- Department of Biological and Environmental Sciences, Alabama A&M University, Normal, AL 35762, USA
| | - Shengjun Wu
- Key Laboratory of Reservoir Aquatic Environment & Research Center for Ecological Process of Three Gorges' Eco-Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Yegang Wu
- Institute of Eco-city Planning and Design, Shanghai BoDa Development Corporation, Shanghai 200333, China
| | - Jinyue Yan
- KTH-Royal Institute of Technology, SE-10044 Stockholm, Sweden & Malardalen University, SE-72123 Vasteras, Sweden
| | - Chuanbo Guo
- Institute of Hydrobiology & State Key Laboratory of Freshwater Ecology and Biotechnology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Wei Xin
- Institute of Hydrobiology & State Key Laboratory of Freshwater Ecology and Biotechnology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Hao Wang
- State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
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Affiliation(s)
- Alice C. Hughes
- Centre for Integrative Conservation; Xishuangbanna Tropical Botanical Garden; Chinese Academy of Sciences; Menglun Jinghong 666303 China
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Chen W, Shen Y, Gan X, Wang X, He S. Genetic diversity and evolutionary history of the Schizothorax species complex in the Lancang River (upper Mekong). Ecol Evol 2016; 6:6023-36. [PMID: 27648223 PMCID: PMC5016629 DOI: 10.1002/ece3.2319] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 06/20/2016] [Accepted: 06/21/2016] [Indexed: 11/28/2022] Open
Abstract
The genus Schizothorax (Cyprinidae), one of the most diverse genera of ichthyofauna of the Qinghai‐Tibetan Plateau (QTP), is a good candidate for investigating patterns of genetic variation and evolutionary mechanisms. In this study, sequences from the mitochondrial control region, the cytochrome b gene, and two nuclear genes were used to re‐examine the genetic diversity and investigate the evolutionary history of the Schizothorax species complex inhabiting the Lancang River. Three maternal clades were detected in the Schizothorax species complex, but frequent nuclear allele sharing also occurred among the three maternal clades. A discrepancy between topologies of mitochondrial and nuclear loci might result from introgression or/and incomplete lineage sorting. The divergence of the clades of the Schizothorax species complex was closely related to the Late Pliocene and Early Pleistocene orogenesis of the QTP and Southwest Mountains of China. Demographic analyses indicated that the species complex subsequently persisted in situ with stable populations during Pleistocene glacial cycling, which suggested that Pleistocene climate changes did not exert a remarkable influence on the species complex. Our study provides a comprehensive analysis of the genetic diversity and evolutionary history of the Schizothorax species complex in the Lancang River.
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Affiliation(s)
- Weitao Chen
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences Wuhan Hubei 430072 China; Graduate School of Chinese Academy of Sciences Beijing 10001 China
| | - Yanjun Shen
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences Wuhan Hubei 430072 China; Graduate School of Chinese Academy of Sciences Beijing 10001 China
| | - Xiaoni Gan
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences Wuhan Hubei 430072 China
| | - Xuzhen Wang
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences Wuhan Hubei 430072 China
| | - Shunping He
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences Wuhan Hubei 430072 China
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30
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Chapman AD, Darby SE, Hồng HM, Tompkins EL, Van TPD. Adaptation and development trade-offs: fluvial sediment deposition and the sustainability of rice-cropping in An Giang Province, Mekong Delta. CLIMATIC CHANGE 2016; 137:593-608. [PMID: 32355372 PMCID: PMC7175674 DOI: 10.1007/s10584-016-1684-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 04/20/2016] [Indexed: 05/24/2023]
Abstract
Deltas around the globe are facing a multitude of intensifying environmental change and development-linked pressures. One key concern is the reduction in the quantity of suspended sediment reaching and building floodplains. Sediment deposition provides multiple services to deltaic social-ecological systems, in particular, countering the subsidence of the delta-body, and providing plentiful nutrients. Experiencing particularly rapid change is the Vietnamese Mekong Delta (VMD). In An Giang Province an increasing number of high dyke rings, which exclude the flood and facilitate triple rice-cropping, simultaneously prevent much of the sediment load from reaching the floodplain. This paper explores the trade-offs implicit in the decision to shift from (i) doublecropping (higher sediment deposition) to (ii) triple cropping (lower sediment deposition) by asking: what is the impact of the shift on VMD farmers? Is it sustainable? And what is the significance of the associated sediment exclusion? A novel survey of An Giang rice farmers was conducted, investigating key agricultural practices, and uniquely, the farmers' estimates of annual sediment deposition depth. The survey elicits some key changes under the adapted system (ii), particularly, unsustainable trajectories in the yield to fertiliser ratio which penalise land-poor farmers. Furthermore, the value (to farmers) of the sediment contribution to agricultural fertilisation which is lost due to triple-cropping is estimated at USD 15 (±5) million annually. We argue that our growing understanding of the importance of sediment in the deltaic social-ecological system may be revealing an emergent risk; arising from conflicting long and short-term adaptation and agricultural development objectives.
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Affiliation(s)
| | - Stephen E. Darby
- Geography & Environment, University of Southampton, Southampton, SO17 1BJ UK
| | - Hoàng M. Hồng
- Research Institute for Climate Change, Can Tho University, Can Tho, Vietnam
| | - Emma L. Tompkins
- Geography & Environment, University of Southampton, Southampton, SO17 1BJ UK
| | - Tri P. D. Van
- College of Environment and Natural Resources, Can Tho University, Can Tho, Vietnam
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Chea R, Grenouillet G, Lek S. Evidence of Water Quality Degradation in Lower Mekong Basin Revealed by Self-Organizing Map. PLoS One 2016; 11:e0145527. [PMID: 26731522 PMCID: PMC4701190 DOI: 10.1371/journal.pone.0145527] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 12/04/2015] [Indexed: 11/19/2022] Open
Abstract
To reach a better understanding of the spatial variability of water quality in the Lower Mekong Basin (LMB), the Self-Organizing Map (SOM) was used to classify 117 monitoring sites and hotspots of pollution within the basin identified according to water quality indicators and US-EPA guidelines. Four different clusters were identified based on their similar physicochemical characteristics. The majority of sites in upper (Laos and Thailand) and middle part (Cambodia) of the basin were grouped in two clusters, considered as good quality water with high DO and low nutrient levels. The other two clusters were mostly composed of sites in Mekong delta (Vietnam) and few sites in upstream tributaries (i.e., northwestern Thailand, Tonle Sap Lake, and swamps close to Vientiane), known for moderate to poor quality of water and characterized by high nutrient and dissolved solid levels. Overall, we found that the water in the mainstream was less polluted than its tributaries; eutrophication and salinity could be key factors affecting water quality in LMB. Moreover, the seasonal variation of water quality seemed to be less marked than spatial variation occurring along the longitudinal gradient of Mekong River. Significant degradations were mainly associated with human disturbance and particularly apparent in sites distributed along the man-made canals in Vietnam delta where population growth and agricultural development are intensive.
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Affiliation(s)
- Ratha Chea
- CNRS, Université Toulouse III Paul Sabatier, ENFA, UMR5174 EDB (Laboratoire Évolution & Diversité Biologique), 118 route de Narbonne, F-31062 Toulouse, France
- Faculty of Agriculture and Food Processing, University of Battambang, Road 5, Battambang City, Cambodia
- * E-mail:
| | - Gaël Grenouillet
- CNRS, Université Toulouse III Paul Sabatier, ENFA, UMR5174 EDB (Laboratoire Évolution & Diversité Biologique), 118 route de Narbonne, F-31062 Toulouse, France
| | - Sovan Lek
- CNRS, Université Toulouse III Paul Sabatier, ENFA, UMR5174 EDB (Laboratoire Évolution & Diversité Biologique), 118 route de Narbonne, F-31062 Toulouse, France
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Xing Y, Zhang C, Fan E, Zhao Y. Freshwater fishes of China: species richness, endemism, threatened species and conservation. DIVERS DISTRIB 2015. [DOI: 10.1111/ddi.12399] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Affiliation(s)
- Yingchun Xing
- Key Laboratory of Zoological Systematics and Evolution; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- Natural Resource and Environment Research Center; Chinese Academy of Fishery Sciences; Beijing China
| | - Chunguang Zhang
- National Zoological Museum; Institute of Zoology; Chinese Academy of Sciences; Beijing China
| | - Enyuan Fan
- Natural Resource and Environment Research Center; Chinese Academy of Fishery Sciences; Beijing China
| | - Yahui Zhao
- Key Laboratory of Zoological Systematics and Evolution; Institute of Zoology; Chinese Academy of Sciences; Beijing China
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33
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Chen W, Ma X, Shen Y, Mao Y, He S. The fish diversity in the upper reaches of the Salween River, Nujiang River, revealed by DNA barcoding. Sci Rep 2015; 5:17437. [PMID: 26616046 PMCID: PMC4663501 DOI: 10.1038/srep17437] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 10/29/2015] [Indexed: 11/09/2022] Open
Abstract
Nujiang River (NR), an essential component of the biodiversity hotspot of the
Mountains of Southwest China, possesses a characteristic fish fauna and contains
endemic species. Although previous studies on fish diversity in the NR have
primarily consisted of listings of the fish species observed during field
collections, in our study, we DNA-barcoded 1139 specimens belonging to 46
morphologically distinct fish species distributed throughout the NR basin by
employing multiple analytical approaches. According to our analyses, DNA barcoding
is an efficient method for the identification of fish by the presence of barcode
gaps. However, three invasive species are characterized by deep conspecific
divergences, generating multiple lineages and Operational Taxonomic Units (OTUs),
implying the possibility of cryptic species. At the other end of the spectrum, ten
species (from three genera) that are characterized by an overlap between their
intra- and interspecific genetic distances form a single genetic cluster and share
haplotypes. The neighbor-joining phenogram, Barcode Index Numbers (BINs) and
Automatic Barcode Gap Discovery (ABGD) identified 43 putative species, while the
General Mixed Yule-coalescence (GMYC) identified five more OTUs. Thus, our study
established a reliable DNA barcode reference library for the fish in the NR and
sheds new light on the local fish diversity.
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Affiliation(s)
- Weitao Chen
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China.,Graduate school of Chinese Academy of Sciences, Beijing, 10001, China
| | - Xiuhui Ma
- School of life science, Southwest University, Beibei, Chongqing, 400715, China
| | - Yanjun Shen
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China.,Graduate school of Chinese Academy of Sciences, Beijing, 10001, China
| | - Yuntao Mao
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China.,Graduate school of Chinese Academy of Sciences, Beijing, 10001, China
| | - Shunping He
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China
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Hegg JC, Giarrizzo T, Kennedy BP. Diverse Early Life-History Strategies in Migratory Amazonian Catfish: Implications for Conservation and Management. PLoS One 2015; 10:e0129697. [PMID: 26153984 PMCID: PMC4496080 DOI: 10.1371/journal.pone.0129697] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 05/12/2015] [Indexed: 12/05/2022] Open
Abstract
Animal migrations provide important ecological functions and can allow for increased biodiversity through habitat and niche diversification. However, aquatic migrations in general, and those of the world's largest fish in particular, are imperiled worldwide and are often poorly understood. Several species of large Amazonian catfish carry out some of the longest freshwater fish migrations in the world, travelling from the Amazon River estuary to the Andes foothills. These species are important apex predators in the main stem rivers of the Amazon Basin and make up the region's largest fishery. They are also the only species to utilize the entire Amazon Basin to complete their life cycle. Studies indicate both that the fisheries may be declining due to overfishing, and that the proposed and completed dams in their upstream range threaten spawning migrations. Despite this, surprisingly little is known about the details of these species' migrations, or their life history. Otolith microchemistry has been an effective method for quantifying and reconstructing fish migrations worldwide across multiple spatial scales and may provide a powerful tool to understand the movements of Amazonian migratory catfish. Our objective was to describe the migratory behaviors of the three most populous and commercially important migratory catfish species, Dourada (Brachyplatystoma rousseauxii), Piramutaba (Brachyplatystoma vaillantii), and Piraíba (Brachyplatystoma filamentosum). We collected fish from the mouth of the Amazon River and the Central Amazon and used strontium isotope signatures ((87)Sr/(86)Sr) recorded in their otoliths to determine the location of early rearing and subsequent. Fish location was determined through discriminant function classification, using water chemistry data from the literature as a training set. Where water chemistry data was unavailable, we successfully in predicted (87)Sr/(86)Sr isotope values using a regression-based approach that related the geology of the upstream watershed to the Sr isotope ratio. Our results provide the first reported otolith microchemical reconstruction of Brachyplatystoma migratory movements in the Amazon Basin. Our results indicate that juveniles exhibit diverse rearing strategies, rearing in both upstream and estuary environments. This contrasts with the prevailing understanding that juveniles rear in the estuary before migrating upstream; however, it is supported by some fisheries data that has indicated the presence of alternate spawning and rearing life-histories. The presence of alternate juvenile rearing strategies may have important implications for conservation and management of the fisheries in the region.
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Affiliation(s)
- Jens C. Hegg
- Department of Fish and Wildlife Sciences, University of Idaho, Moscow, Idaho, United States of America
| | - Tommaso Giarrizzo
- Laboratório de Biologia Pesqueira—Manejo dos Recursos Aquáticos, Universidade Federal do Pará (UFPA), Belém, PA, Brazil
| | - Brian P. Kennedy
- Department of Fish and Wildlife Sciences, University of Idaho, Moscow, Idaho, United States of America
- Departments of Geological Sciences and Biological Sciences, University of Idaho, Moscow, Idaho, United States of America
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Haidvogl G, Hoffmann R, Pont D, Jungwirth M, Winiwarter V. Historical ecology of riverine fish in Europe. AQUATIC SCIENCES 2015; 77:315-324. [PMID: 26321853 PMCID: PMC4550263 DOI: 10.1007/s00027-015-0400-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 06/27/2015] [Indexed: 06/04/2023]
Abstract
The temporal dynamic of riverine ecosystems and their fish communities and populations has been addressed in ecological theory and management for several decades. A growing number of case studies on the historic development especially of European and North American rivers have been published. Nonetheless, a theoretical debate about the contributions and limits of historical approaches and interdisciplinary co-operation is lacking. This article presents a brief overview of the role of history in river and fish ecology and suggests historical ecology as a scientific field that can offer a framework for future research. Based on case studies compiled in this special issue on the "Historical ecology of riverine fish in Europe", we draw conclusions on long-term changes of fish communities, on fisheries, aquatic ecosystem management and past habitat alterations and the potential of archaeological remains and written sources to study them. We discuss how modelling of historical fish data can help elucidate the effects of climate change and human influences on rivers and fish. Finally, we account for the necessity to consider appropriate spatial and temporal scales. In conclusion we call for future comparative studies on continental and global scales and methodological development, which can benefit especially from recent advances in marine historical ecology. We suggest that future interdisciplinary studies of ecologists, hydrologists, historians and archaeologists can reveal the history of riverine ecosystems as socio-ecological systems, addressing both their natural dynamics and human dimension. Such an endeavor can also support developing management plans for habitat restoration and conservation against the background of global change.
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Affiliation(s)
- Gertrud Haidvogl
- />Institute of Hydrobiology and Aquatic Ecosystem Management, University of Natural Resources and Life Sciences Vienna, Max Emanuelstraße 17, 1180 Vienna, Austria
| | - Richard Hoffmann
- />Department of History, 2140 Vari Hall, York University, 4700 Keele St., Toronto, ON M3J 1P3 Canada
| | - Didier Pont
- />Irstea UR HBAN, 1 rue Pierre-Gilles de Gennes—CS 10030, 92761 Antony, France
| | - Mathias Jungwirth
- />Institute of Hydrobiology and Aquatic Ecosystem Management, University of Natural Resources and Life Sciences Vienna, Max Emanuelstraße 17, 1180 Vienna, Austria
| | - Verena Winiwarter
- />Faculty of Interdisciplinary Studies, Institute of Social Ecology, Alpen-Adria-Universität Klagenfurt, Schottenfeldgasse 29, 1070 Vienna, Austria
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Pinder AC, Raghavan R, Britton JR. The legendary hump-backed mahseer Tor sp. of India’s River Cauvery: an endemic fish swimming towards extinction? ENDANGER SPECIES RES 2015. [DOI: 10.3354/esr00673] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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37
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Trends in Stream Biodiversity Research since the River Continuum Concept. DIVERSITY-BASEL 2015. [DOI: 10.3390/d7010016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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38
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Chen W, Du K, He S. Genetic structure and historical demography of Schizothorax nukiangensis (Cyprinidae) in continuous habitat. Ecol Evol 2015; 5:984-95. [PMID: 25750724 PMCID: PMC4338980 DOI: 10.1002/ece3.1413] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Revised: 01/07/2015] [Accepted: 01/12/2015] [Indexed: 11/24/2022] Open
Abstract
Geographic distance, different living habitats or Pleistocene climatic oscillations have frequently been found to shape population genetic structure in many species. The genetic structure of Schizothorax nukiangensis, a high altitude, valuable fish species, which is distributed throughout the Nujiang River, was investigated by mitochondrial DNA sequence analysis. The cytochrome c oxidase subunit I (COI), cytochrome b (cytb), and the mitochondrial control region (MCR) of S. nukiangensis were concatenated for examination of population structure and demographic history. The concatenated data set (2405 bp) implied a pronounced genetic population structure (overall FST = 0.149) and defined two population units. Strong differentiation was detected between the Sanjiangkou (SJK) population and other populations due to environmental heterogeneity, dispersal ability, and/or glacial cycles. Additional DNA sequencing of the nuclear RAG2 gene also examined significant differentiation between two units and between SJK and the upstream populations (U-unit). Recent expansion events suggest that S. nukiangensis may have undergone a rapid increase during warm interglacial periods. Surprisingly, S. nukiangensis appears to have undergone an obvious expansion during the last glaciations (LG) for cold hardiness and a sharp contraction from 1.5 ka to the present. However, two population units exhibited different reflections during the LG, which might be closely related to their living habitats and cold hardiness. A clear pattern of isolation by distance was detected in S. nukiangensis due to feeding habits, limited dispersal ability, and/or philopatry. It is vitally important that more attention be given to S. nukiangensis due to low genetic diversity, lack of gene flow, and recent population contraction.
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Affiliation(s)
- Weitao Chen
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences Wuhan, Hubei, 430072, China ; University of Chinese Academy of Sciences Beijing, 100049, People's Republic of China
| | - Kang Du
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences Wuhan, Hubei, 430072, China ; University of Chinese Academy of Sciences Beijing, 100049, People's Republic of China
| | - Shunping He
- The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences Wuhan, Hubei, 430072, China
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Starrs D, Ebner BC, Fulton CJ. All in the ears: unlocking the early life history biology and spatial ecology of fishes. Biol Rev Camb Philos Soc 2014; 91:86-105. [DOI: 10.1111/brv.12162] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2014] [Revised: 10/16/2014] [Accepted: 10/22/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Danswell Starrs
- Evolution, Ecology and Genetics; Research School of Biology, Australian National University; Canberra Australian Capital Territory 0200 Australia
| | - Brendan C. Ebner
- CSIRO Ecosystem Sciences; Atherton Queensland 4883 Australia
- TropWATER, James Cook University; Townsville Queensland 4811 Australia
| | - Christopher J. Fulton
- Evolution, Ecology and Genetics; Research School of Biology, Australian National University; Canberra Australian Capital Territory 0200 Australia
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40
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Pinlaor S, Onsurathum S, Boonmars T, Pinlaor P, Hongsrichan N, Chaidee A, Haonon O, Limviroj W, Tesana S, Kaewkes S, Sithithaworn P. Distribution and abundance of Opisthorchis viverrini metacercariae in cyprinid fish in Northeastern Thailand. THE KOREAN JOURNAL OF PARASITOLOGY 2013; 51:703-10. [PMID: 24516277 PMCID: PMC3916461 DOI: 10.3347/kjp.2013.51.6.703] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/12/2013] [Accepted: 10/11/2013] [Indexed: 11/23/2022]
Abstract
To increase public health awareness for prevention of opisthorchiasis caused by eating raw freshwater fish, the distribution and abundance of Opisthorchis viverrini metacercariae (OV MC) was investigated in freshwater fish obtained from 20 provinces in northeastern Thailand between April 2011 and February 2012. A cross-sectional survey was conducted on 12,890 fish consisting of 13 species randomly caught from 26 rivers, 10 dams, and 38 ponds/lakes. Fish, were collected in each of the rainy and winter seasons from each province. Fish were identified, counted, weighed, and digested using pepsin-HCl. Samples were examined for OV MC by a sedimentation method, and metacercariae were identified under a stereomicroscope. OV MC were found in 6 species of fish; i.e., Cyclocheilichthys armatus, Puntius orphoides, Hampala dispar, Henicorhynchus siamensis, Osteochilus hasselti, and Puntioplites proctozysron from localities in 13 provinces. Among the sites where OV MC-infected fish were found, 70.0% were dams, 23.7% were ponds/lakes, and 7.7% were rivers. The mean intensity of OV MC ranged from 0.01 to 6.5 cysts per fish (or 1.3-287.5 cysts per kg of fish). A high mean intensity of OV MC per fish (>3 cysts) was found in 5 provinces: Amnat Charoen (6.5 cysts), Nakhon Phanom (4.3), Mukdahan (4.1), Khon Kaen, (3.5) and Si Sa Ket (3.4). In conclusion, OV MC are prevalent in natural cyprinid fish, with the infection rate varying according to fish species and habitats.
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Affiliation(s)
- Somchai Pinlaor
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. ; Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Sudarat Onsurathum
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. ; Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Thidarut Boonmars
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. ; Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Porntip Pinlaor
- Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. ; Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Nuttanan Hongsrichan
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. ; Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Apisit Chaidee
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. ; Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Ornuma Haonon
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. ; Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Wutipong Limviroj
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Smarn Tesana
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. ; Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Sasithorn Kaewkes
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. ; Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Paiboon Sithithaworn
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. ; Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
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Attwood SW, Upatham ES. A population growth trend analysis for Neotricula aperta, the snail intermediate host of Schistosoma mekongi, after construction of the Pak-Mun dam. PLoS Negl Trop Dis 2013; 7:e2539. [PMID: 24244775 PMCID: PMC3820754 DOI: 10.1371/journal.pntd.0002539] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Accepted: 09/30/2013] [Indexed: 02/05/2023] Open
Abstract
Background The Pak-Mun dam is a controversial hydro-power project on the Mun River in Northeast Thailand. The dam is sited in a habitat of the freshwater snail Neotricula aperta, which is the intermediate host for the parasitic blood-fluke Schistosoma mekongi causing Mekong schistosomiasis in humans in Cambodia and Laos. Few data are available which can be used to assess the effects of water resource development on N. aperta. The aim of this study was to obtain data and to analyze the possible impact of the dam on N. aperta population growth. Methodology/Principal Findings Estimated population densities were recorded for an N. aperta population in the Mun River 27 km upstream of Pak-Mun, from 1990 to 2011. The Pak-Mul dam began to operate in 1994. Population growth was modeled using a linear mixed model expression of a modified Gompertz stochastic state-space exponential growth model. The N. aperta population was found to be quite stable, with the estimated growth parameter not significantly different from zero. Nevertheless, some marked changes in snail population density were observed which were coincident with changes in dam operation policy. Conclusions/Significance The study found that there has been no marked increase in N. aperta population growth following operation of the Pak-Mun dam. The analysis did indicate a large and statistically significant increase in population density immediately after the dam came into operation; however, this increase was not persistent. The study has provided the first vital baseline data on N. aperta population behavior near to the Pak-Mun dam and suggests that the operation policy of the dam may have an impact on snail population density. Nevertheless, additional studies are required for other N. aperta populations in the Mun River and for an extended time series, to confirm or refine the findings of this work. There is much controversy over the effects of water resource development on the transmission of schistosomiasis in the lower Mekong Basin. Impact assessments are urgently required because there are currently 12 such projects planned in the region. The key to understanding the effects of impoundment is the impact on the snail intermediate host, which, in the case of Mekong schistosomiasis, is Neotricula aperta. Surprisingly, we have almost no data on N. aperta population trends nor on the impact of dams. To address this, the present work focused on a population near the Pak-Mun dam in Thailand. The analysis suggested that N. aperta populations were not growing significantly over the study period (1990–2011), but that the dam may have affected a spike in population density immediately after its completion. The study also revealed changes in density that were coincident on changes in operation of the dam; suggesting that keeping the dam open might lower snail population densities. This is the first scientific assessment of the impact of the Pak-Mun dam on N. aperta and suggests that dams of this kind may affect snail population density. The study also indicates an urgent need for additional independent observations and continuing regular surveys.
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Affiliation(s)
- Stephen W. Attwood
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, People's Republic of China
- Department of Life Sciences, The Natural History Museum, London, United Kingdom
- * E-mail:
| | - E. Suchart Upatham
- Faculty of Allied Health Sciences, Burapha University, Bangsaen, Chonburi, Thailand
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Centuries of Anadromous Forage Fish Loss: Consequences for Ecosystem Connectivity and Productivity. Bioscience 2012. [DOI: 10.1525/bio.2012.62.8.5] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Attwood SW, Upatham ES. Observations on Neotricula aperta (Gastropoda: Pomatiopsidae) population densities in Thailand and central Laos: implications for the spread of Mekong schistosomiasis. Parasit Vectors 2012; 5:126. [PMID: 22720904 PMCID: PMC3434010 DOI: 10.1186/1756-3305-5-126] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 06/21/2012] [Indexed: 02/05/2023] Open
Abstract
Background The snail Neotricula aperta transmits Mekong schistosomiasis in southern Laos and Cambodia, with about 1.5 million people at risk of infection. Plans are under consideration for at least 12 hydroelectric power dams on the lower Mekong river and much controversy surrounds predictions of their environmental impacts. Unfortunately, there are almost no ecological data (such as long term population trend studies) available for N. aperta which could be used in impact assessment. Predictions currently assume that the impacts will be the same as those observed in Africa (i.e., a worsening of the schistosomiasis problem); however, marked ecological differences between the snails involved suggest that region specific models are required. The present study was performed as an initial step in providing data, which could be useful in the planning of water resource development in the Mekong. Snail population density records were analyzed for populations close to, and far downstream of, the Nam Theun 2 (NT2) project in Laos in order to detect any changes that might be attributable to impoundment. Results The population immediately downstream of NT2 and that sampled 400 km downstream in Thailand both showed a long term trend of slow growth from 1992 to 2005; however, both populations showed a marked decline in density between 2005 and 2011. The decline in Thailand was to a value significantly lower than that predicted by a linear mixed model for the data, whilst the population density close to NT2 fell to undetectable levels in 2011 from densities of over 5000 m-2 in 2005. The NT2 dam began operation in 2010. Conclusions The impact of the NT2 dam on N. aperta population density could be more complex than first thought and may reflect the strict ecological requirements of this snail. There was no indication that responses of N. aperta populations to dam construction are similar to those observed with Bulinus and Schistosoma haematobium in Africa, for example. In view of the present findings, more ecological data (in particular population density monitoring and surveillance for new habitats) are urgently required in order to understand properly the likely impacts of water resource development on Mekong schistosomiasis.
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Affiliation(s)
- Stephen W Attwood
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, People's Republic of China.
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