1
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Chan JCF, Liew JH, Dudgeon D. High spatial variability in a species-rich assemblage of diadromous fishes in Hong Kong, southern China. JOURNAL OF FISH BIOLOGY 2024. [PMID: 38831621 DOI: 10.1111/jfb.15812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 05/09/2024] [Accepted: 05/11/2024] [Indexed: 06/05/2024]
Abstract
China has experienced substantial coastal reclamation and damming of rivers. These changes have the potential to impact migrations of diadromous fishes between the sea and fresh waters, but the composition of these fishes and the impacts of barriers to their movement in China have received little attention. We inventoried the species composition and distribution of diadromous fishes, and the impacts of barriers on them, in the Hong Kong Special Administrative Region (HKSAR), southern China. Fish assemblages were surveyed using hand-nets, supplemented by cast-netting and single-pass snorkel surveys, in 24 small coastal streams across three regions. Surveys were undertaken on multiple occasions during the wet and dry seasons to account for the monsoonal tropical climate. Twenty-eight diadromous fishes were collected, mostly gobies, amounting to over half (53%) of the total richness of primary freshwater fishes; four additional species are known from literature records. Diadromous richness was 48% greater during the wet season, when all species were encountered. Richness varied substantially among streams, from a maximum of 17 (2 streams that were diversity hot spots) to none (3 streams). The most widespread diadromous fish was Glossogobius giuris (71% frequency of occurrence), followed by Mugil cephalus (58% occurrence) and Eleotris oxycephala (50% occurrence). The remaining 25 diadromous fishes occurred in fewer than half of the streams; 12 species were confined to a single stream and may be locally threatened. There were conspicuous spatial differences in diadromous assemblages across HKSAR, despite its limited extent (1114 km2), the proximity of the surveyed streams, and the broad geographic distribution of most species. Regional species assemblages were influenced by localized habitat characteristics, with a noticeable distinction between areas with and without large, fast-flowing, and highly oxygenated streams. The presence of in-stream barriers (weirs: 0.3-8.7 m high) did not affect spatial patterns in species assemblages, although, on average, diadromous richness was lower in weir-obstructed streams (4.0 vs. 6.9 species in unobstructed streams). In total, 18 species were confined to unobstructed streams or sections below weirs, whereas the remaining 10 species were recorded both above and below weirs. Only the mottled eel (Anguilla marmorata) and a goby (Stiphodon multisquamus) were able to ascend weirs over 2 m. Although at least 400 m of the lower course of each stream was sampled, diadromous fishes were confined to the first 300 m in 12 of the 13 weir-obstructed streams. Remarkably, the tally of 32 diadromous species in HKSAR exceeds the 19 known from mainland China, highlighting the need for further research on composition and conservation status of diadromous fishes.
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Affiliation(s)
- Jeffery C F Chan
- School of Biological Sciences, The University of Hong Kong, Pok Fu Lam, Hong Kong
- Science Unit, Lingnan University, Tuen Mun, Hong Kong
| | - Jia Huan Liew
- School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - David Dudgeon
- School of Biological Sciences, The University of Hong Kong, Pok Fu Lam, Hong Kong
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2
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Li A, Fan J, Guo F, Carpenter-Bundhoo L, Huang G, Shi Y, Ao Y, Wang J. Assessing the impact of river connectivity on fish biodiversity in the Yangtze River Basin using a multi-index evaluation framework. ENVIRONMENTAL RESEARCH 2024; 242:117729. [PMID: 38036204 DOI: 10.1016/j.envres.2023.117729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/11/2023] [Accepted: 11/16/2023] [Indexed: 12/02/2023]
Abstract
The Yangtze River Basin, the world's third-largest river basin and a hot spot for global biodiversity conservation, is facing biodiversity crisis caused by reduced river connectivity. The deterioration arises from four dimensions: longitudinal, lateral, vertical and temporal. However, limited research has quantified the spatiotemporal connectivity of the Yangtze River Basin and further evaluated the consequent impact on fish biodiversity. In our study, a multi-index evaluation framework was developed to assess the variations in the four-dimensional connectivity of the Yangtze River Basin from 1980 to 2020, and fish biodiversity affected by reduced connectivity was detected by environmental DNA metabarcoding. Our results showed that the Yangtze River Basin suffers from a pronounced connectivity reduction, with 67% of assessed rivers experiencing deteriorated connectivity in recent years. The lost fish biodiversity along the river reaches with the worst connectivity was likely attributed to the construction of hydropower plants. The headwaters and the downstreams of most hydropower plants had a higher fish biodiversity compared with reservoirs. The free-flowing reaches in the downstream of the lowest hydropower station, had higher lotic fish abundance compared with that in the upstream. As for the entire Yangtze River Basin, 67% of threatened fish species, with 70% endemic species, were threatened by reduced river connectivity. Our result indicates that the massive loss of river connectivity changes the spatiotemporal patterns of fish community and threatens protected fish. More effective measures to restore the populations of affected fish in rivers with reduced river connectivity are required.
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Affiliation(s)
- Aopu Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Juntao Fan
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
| | - Fen Guo
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | | | - Guoxian Huang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Yue Shi
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Yuyin Ao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Jingfu Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
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3
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Sonnino Sorisio G, Müller S, Wilson CA, Ouro P, Cable J. Colour as a behavioural guide for fish near hydrokinetic turbines. Heliyon 2023; 9:e22376. [PMID: 38046155 PMCID: PMC10686872 DOI: 10.1016/j.heliyon.2023.e22376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/26/2023] [Accepted: 11/10/2023] [Indexed: 12/05/2023] Open
Abstract
Hydropower is a traditional and widespread form of renewable energy and vertical axis turbines are an emerging technology suitable for low to medium velocity water bodies such as rivers. Such devices can provide renewable power to remote communities but may also contribute to fragmenting already poorly connected riverine habitats and the impact could be particularly pronounced for migratory diadromous aquatic species such as salmonids by limiting their ability to pass the turbines. Optimising the design of such turbines is therefore essential to mitigate their impact on aquatic fauna. One easily altered property that does not impact turbine performance is blade colour. Here, juvenile rainbow trout (Oncorhynchus mykiss) free swimming within a flume were monitored in the presence of a vertical axis turbine that was either stationary or rotating, and coloured white or orange. The orange colour of the turbine affected behaviour by increasing turbine avoidance and decreasing the number of potentially harmful interactions with the turbine when it was rotating, whilst not affecting passage or mobility of the trout compared to the white turbine. Visibility is therefore a potentially useful tool in mitigating the environmental impact of hydrokinetic turbines.
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Affiliation(s)
| | | | | | - Pablo Ouro
- School of Engineering, Cardiff University, CF24 3AA, UK
- School of Engineering, University of Manchester, M13 9PL, UK
| | - Jo Cable
- School of Biosciences, Cardiff University, CF10 3AX, UK
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4
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McFadden IR, Sendek A, Brosse M, Bach PM, Baity-Jesi M, Bolliger J, Bollmann K, Brockerhoff EG, Donati G, Gebert F, Ghosh S, Ho HC, Khaliq I, Lever JJ, Logar I, Moor H, Odermatt D, Pellissier L, de Queiroz LJ, Rixen C, Schuwirth N, Shipley JR, Twining CW, Vitasse Y, Vorburger C, Wong MKL, Zimmermann NE, Seehausen O, Gossner MM, Matthews B, Graham CH, Altermatt F, Narwani A. Linking human impacts to community processes in terrestrial and freshwater ecosystems. Ecol Lett 2023; 26:203-218. [PMID: 36560926 PMCID: PMC10107666 DOI: 10.1111/ele.14153] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 11/14/2022] [Accepted: 11/14/2022] [Indexed: 12/24/2022]
Abstract
Human impacts such as habitat loss, climate change and biological invasions are radically altering biodiversity, with greater effects projected into the future. Evidence suggests human impacts may differ substantially between terrestrial and freshwater ecosystems, but the reasons for these differences are poorly understood. We propose an integrative approach to explain these differences by linking impacts to four fundamental processes that structure communities: dispersal, speciation, species-level selection and ecological drift. Our goal is to provide process-based insights into why human impacts, and responses to impacts, may differ across ecosystem types using a mechanistic, eco-evolutionary comparative framework. To enable these insights, we review and synthesise (i) how the four processes influence diversity and dynamics in terrestrial versus freshwater communities, specifically whether the relative importance of each process differs among ecosystems, and (ii) the pathways by which human impacts can produce divergent responses across ecosystems, due to differences in the strength of processes among ecosystems we identify. Finally, we highlight research gaps and next steps, and discuss how this approach can provide new insights for conservation. By focusing on the processes that shape diversity in communities, we aim to mechanistically link human impacts to ongoing and future changes in ecosystems.
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Affiliation(s)
- Ian R McFadden
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland.,Institute of Terrestrial Ecosystems, ETH Zürich, Zurich, Switzerland
| | - Agnieszka Sendek
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland.,Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Morgane Brosse
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Peter M Bach
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Marco Baity-Jesi
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Janine Bolliger
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
| | - Kurt Bollmann
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
| | - Eckehard G Brockerhoff
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland.,School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
| | - Giulia Donati
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Friederike Gebert
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
| | - Shyamolina Ghosh
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
| | - Hsi-Cheng Ho
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Imran Khaliq
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - J Jelle Lever
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland.,Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Ivana Logar
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Helen Moor
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland.,Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Daniel Odermatt
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Loïc Pellissier
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland.,Institute of Terrestrial Ecosystems, ETH Zürich, Zurich, Switzerland
| | - Luiz Jardim de Queiroz
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Kastanienbaum, Switzerland.,Institute of Ecology & Evolution, University of Bern, Bern, Switzerland
| | - Christian Rixen
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Davos, Switzerland
| | - Nele Schuwirth
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - J Ryan Shipley
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Kastanienbaum, Switzerland
| | - Cornelia W Twining
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Kastanienbaum, Switzerland
| | - Yann Vitasse
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
| | - Christoph Vorburger
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland.,Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zürich, Zurich, Switzerland
| | - Mark K L Wong
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland.,School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Niklaus E Zimmermann
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
| | - Ole Seehausen
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Kastanienbaum, Switzerland.,Institute of Ecology & Evolution, University of Bern, Bern, Switzerland
| | - Martin M Gossner
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland.,Institute of Terrestrial Ecosystems, ETH Zürich, Zurich, Switzerland
| | - Blake Matthews
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Kastanienbaum, Switzerland
| | - Catherine H Graham
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
| | - Florian Altermatt
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland.,Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zürich, Switzerland
| | - Anita Narwani
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
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5
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Garcia de Leaniz C, O'Hanley JR. Operational methods for prioritizing the removal of river barriers: Synthesis and guidance. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 848:157471. [PMID: 35868378 DOI: 10.1016/j.scitotenv.2022.157471] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/30/2022] [Accepted: 07/14/2022] [Indexed: 06/15/2023]
Abstract
Barrier removal can be an efficient method to restore river continuity but resources available for defragmenting rivers are limited and a prioritization strategy is needed. We review methods for prioritizing barriers for removal and report on a survey asking practitioners which barrier prioritization methods they use. Opportunities for barrier removal depend to a large extent on barrier typology, as this dictates where barriers are normally located, their size, age, condition, and likely impacts. Crucially, river fragmentation depends chiefly on the number and location of barriers, not on barrier size, while the costs of barrier removal typically increase with barrier height. Acting on many small barriers will often be more cost-efficient than acting on fewer larger structures. Barriers are not randomly distributed and a small proportion of barriers have a disproportionately high impact on fragmentation, therefore targeting these 'fragmentizers' can result in substantial gains in connectivity. Barrier prioritization methods can be grouped into six main types depending on whether they are reactive or proactive, whether they are applied at local or larger spatial scales, and whether they employ an informal or a formal approach. While mathematical optimization sets the gold standard for barrier prioritization, a hybrid approach that explicitly considers uncertainties and opportunities is likely to be the most effective. The effectiveness of barrier removal can be compromised by inaccurate stream networks, erroneous barrier coordinates, and underestimation of barrier numbers. Such uncertainties can be overcome by ground truthing via river walkovers and predictive modelling, but the cost of collecting additional information must be weighed against the cost of inaction. To increase the success of barrier removal projects, we recommend that barriers considered for removal fulfill four conditions: (1) their removal will bring about a meaningful gain in connectivity; (2) they are cost-effective to remove; (3) they will not cause significant or lasting environmental damage, and (4) they are obsolete structures. Mapping barrier removal projects according to the three axes of opportunities, costs, and gains can help locate any 'low hanging fruit.'
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Affiliation(s)
- Carlos Garcia de Leaniz
- Department of Biosciences, Centre for Sustainable Aquatic Research (CSAR), Swansea University, Swansea, UK.
| | - Jesse R O'Hanley
- Kent Business School, University of Kent, Canterbury, UK; Durrell Institute of Conservation and Ecology, University of Kent, Canterbury, UK
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6
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Fu Y, Liu Y, Xu S, Xu Z. Assessment of a Multifunctional River Using Fuzzy Comprehensive Evaluation Model in Xiaoqing River, Eastern China. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:12264. [PMID: 36231561 PMCID: PMC9565060 DOI: 10.3390/ijerph191912264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 09/20/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Rivers are beneficial to humans due to their multiple functions. However, human meddling substantially degrades the functions of rivers and constitutes a threat to river health. Therefore, it is vital to assess and maintain river function. This study used the Xiaoqing River in Shandong Province, China, as a case study and established a multilayered multifunctional river evaluation indicator system consisting of environmental function, ecological function, social function, and economic function. The weights of indicators were calculated using the analytic hierarchy process (AHP) and the entropy method. Furthermore, a fuzzy comprehensive evaluation model based on the Cauchy distribution function was developed to assess the operation status of each function in each river segment. The results of the indicator and criterion layers in different river sections varied. The multifunctionality of the river decreased from upstream to downstream. The Jinan section was the most multifunctional, followed by the Binzhou, Zibo, and Dongying sections, and finally the Weifang section. Through additional analysis, this study determined the constraint indicators and functions of each river section. Overall, the results reveal that the idea of a "multifunctional river" can advance the theoretical understanding of a river's function, and the fuzzy comprehensive evaluation model is demonstrated to provide fresh perspectives for evaluating river function.
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Affiliation(s)
- Yongfei Fu
- School of Water Conservancy and Environment, University of Jinan, Jinan 250024, China
| | - Yuyu Liu
- School of Water Conservancy and Environment, University of Jinan, Jinan 250024, China
| | - Shiguo Xu
- School of Hydraulic Engineering, Dalian University of Technology, Dalian 116024, China
| | - Zhenghe Xu
- School of Water Conservancy and Environment, University of Jinan, Jinan 250024, China
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7
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Sethi SA, Carey MP, Gerken J, Harris BP, Wolf N, Cunningham C, Restrepo F, Ashline J. Juvenile salmon habitat use drives variation in growth and highlights vulnerability to river fragmentation. Ecosphere 2022. [DOI: 10.1002/ecs2.4192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Suresh A. Sethi
- U.S. Geological Survey, New York Cooperative Fish and Wildlife Research Unit Cornell University Ithaca New York USA
- Fisheries, Aquatic Science and Technology Laboratory Alaska Pacific University Anchorage Alaska USA
| | - Michael P. Carey
- U.S. Geological Survey Alaska Science Center Anchorage Alaska USA
| | - Jonathon Gerken
- U.S. Fish and Wildlife Service Anchorage Field Office Anchorage Alaska USA
| | - Bradley P. Harris
- Fisheries, Aquatic Science and Technology Laboratory Alaska Pacific University Anchorage Alaska USA
| | - Nathan Wolf
- Fisheries, Aquatic Science and Technology Laboratory Alaska Pacific University Anchorage Alaska USA
| | - Curry Cunningham
- Fisheries, Aquatic Science and Technology Laboratory Alaska Pacific University Anchorage Alaska USA
- College of Fisheries and Ocean Sciences University of Alaska Fairbanks Juneau Alaska USA
| | - Felipe Restrepo
- Fisheries, Aquatic Science and Technology Laboratory Alaska Pacific University Anchorage Alaska USA
| | - Joshua Ashline
- Fisheries, Aquatic Science and Technology Laboratory Alaska Pacific University Anchorage Alaska USA
- Bonneville Power Administration Portland Oregon USA
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8
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Bernthal FR, Armstrong JD, Nislow KH, Metcalfe NB. Nutrient limitation in Atlantic salmon rivers and streams: Causes, consequences, and management strategies. AQUATIC CONSERVATION : MARINE AND FRESHWATER ECOSYSTEMS 2022; 32:1073-1091. [PMID: 35915662 PMCID: PMC9314074 DOI: 10.1002/aqc.3811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 02/17/2022] [Accepted: 03/06/2022] [Indexed: 06/16/2023]
Abstract
Freshwater catchments can experience nutrient deficits that result in reduced primary and secondary productivity. The most commonly limiting nutrients are nitrogen and phosphorus, either separately or together. This review considers the impact of increasing nutrient limitation in temperate basin stream and river systems, focusing on upland areas that currently or previously supported wild Atlantic salmon (Salmo salar) populations.Anthropogenic changes to land use and increases in river barriers have altered upland nutrient dynamics, with particular impacts on salmon and other migratory fish species which may be net importers of nutrients to upland streams. Declining salmon populations may further reduce nutrient sources, reducing ecosystem and fisheries productivity below desired levels.Experimental manipulations of nutrient levels have examined the impacts of this cultural oligotrophication. There is evidence that growth and biomass of juvenile salmon can be increased via appropriate additions of nutrients, offering potential as a conservation tool. However, further research is required to understand the long-term effects of these additions on salmon populations and stream ecosystems, and to assess the vulnerability of downstream habitats to eutrophication as a result.Although purposeful nutrient addition with the aim of enhancing and conserving salmonid populations may be justified in some cases, it should be undertaken in an adaptive management framework. In addition, nutrient addition should be linked to nutrient retention and processing, and integrated into large-scale habitat restoration and recovery efforts.Both the scientific and the management community should recognize that the ecological costs and benefits associated with adding nutrients to salmon streams may change in a non-stationary world.
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Affiliation(s)
- Fionn R. Bernthal
- Institute of Biodiversity Animal Health and Comparative MedicineUniversity of GlasgowGlasgowUK
| | - John D. Armstrong
- Marine Scotland – ScienceFreshwater Fisheries LaboratoryFaskallyPitlochryUK
| | - Keith H. Nislow
- USDA Forest Service Northern Research StationAmherstMassachusettsUSA
| | - Neil B. Metcalfe
- Institute of Biodiversity Animal Health and Comparative MedicineUniversity of GlasgowGlasgowUK
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9
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Review of Effects of Dam Construction on the Ecosystems of River Estuary and Nearby Marine Areas. SUSTAINABILITY 2022. [DOI: 10.3390/su14105974] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Dams have made great contributions to human society, facilitating flood control, power generation, shipping, agriculture, and industry. However, the construction of dams greatly impacts downstream ecological environments and nearby marine areas. The present manuscript presents a comprehensive review of the influence of human activities on the environment, especially the effect of dam construction on the ecosystems of river estuaries and nearby marine areas, so as to provide a scientific basis for ecological environment protection. To summarize these impacts, this review used recent studies to comprehensively analyze how dam construction has affected river hydrology, geomorphology, and downstream ecosystems globally. Effects of dams on ecosystems occur through reduced river flow, reduced sediment flux, altered water temperature, changed estuary delta, altered composition and distribution of nutrients, altered structure and distribution of phytoplankton populations, habitat fragmentation, and blocked migration routes in river sections and adjacent seas. Effects of dam construction (especially the Three Gorges Dam) on the Yangtze River were also reviewed. Performing community and mitigation planning before dam construction, exploring new reservoir management strategies (including targeted control of dam storage and flushing sediment operations), banning fishing activities, and removing unnecessary dams (obsolete or small dams) are becoming crucial tools for ecosystem restoration.
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10
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He K, Wang J, Liao P, Sun Q, Yang X, Jin Z, Chen J. Effects of cascade dam on the distribution of heavy metals and biogenic elements in sediments at the watershed scale, Southwest China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:8970-8979. [PMID: 34494191 DOI: 10.1007/s11356-021-16363-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 09/01/2021] [Indexed: 06/13/2023]
Abstract
Cascade dam has important effects on the magnitude and dynamics of sediment particles, heavy metals, and biogenic elements in reservoirs. However, systematic studies on the interception effect of cascade dam on the various elements that occur in rivers at the watershed scale are lacking. The aims of this study were to (1) assess the interception effect of a cascade dam on heavy metals and biogenic elements and (2) investigate the key factors of these effects of the cascade dam. Surface sediments were collected from 29 sites distributed in the Wujiang River Basin (WRB, a watershed scale in Southwest China), including from tributaries (7 sites), the main stream (13 sites), and cascade reservoirs (9 sites). In addition, the particle sizes, heavy metals (Fe, Mn, Zn, Cr, Cu, As, Pb, and Cd), and biogenic elements (TOC, TN, and TP) of sediments were analyzed. Compared with the tributaries, D50 (median particle size) was significantly reduced by 56.8% of cascade reservoirs. The proportion of 63-2,000 μm decreased from 13.78 to 1.34%, indicating that more coarse particles were intercepted in the cascade reservoirs. The contents of heavy metals (Fe, Zn, Cu, As, and Cd) declined significantly along the way. On the whole, the contents of TOC, TN, and TP were highest in the midstream and lower in the upstream and downstream. The hydrological condition (reservoir age, HRT, and flow) and the basin area and internal and external inputs of cascade reservoirs are important factors. The findings deepen the current understanding of the mechanisms by which cascade dam affects the river transport of heavy metals and biogenic elements at the watershed scale and provide an important reference for establishing hydropower developments along rivers and developing aquatic environment management strategies.
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Affiliation(s)
- Kangkang He
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, People's Republic of China
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China
| | - Jingfu Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China.
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
| | - Peng Liao
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Qingqing Sun
- Institute of Surface Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, People's Republic of China
| | - Xiaohong Yang
- College of Resource and Environmental Engineering, Guizhou University, Guiyang, 550025, People's Republic of China
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China
| | - Zuxue Jin
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Jingan Chen
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, People's Republic of China.
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
- CAS Center for Excellence in Quaternary Science and Global Change, Xi'an, 710061, People's Republic of China.
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11
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Costa MJ, Duarte G, Segurado P, Branco P. Major threats to European freshwater fish species. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 797:149105. [PMID: 34303251 DOI: 10.1016/j.scitotenv.2021.149105] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
In Europe, freshwater fish are the richest group amongst European vertebrates and the second most threatened animal group, surpassed only by freshwater molluscs. The identification of threats is a major benefit for conservation efforts, as it allows actions to be bespoke to specific threats imperilling fish communities in sensitive areas. In this work, we analyse all threats identified under the International Union for Conservation of Nature (IUCN) Red List of Threatened Species for all European native freshwater dependent fish and lamprey species and relate them with the species distribution, conservation status and migratory phenology. Results show that the current level of imperilment of European freshwater fish fauna is high, especially in the Iberian Peninsula fish communities where low richness is combined with a proportion of threatened species surpassing 50% in several catchments The most relevant threats affecting European freshwater fish are: "Dams & Water Management/Use", "Droughts", "Invasive Non-Native/Alien Species/Diseases", "Agricultural & Forestry Effluents" and "Fishing & Harvesting Aquatic Resources". The present work contributes to the ultimate goal of species conservation by highlighting the main threats affecting freshwater fish species in Europe and by demonstrating how specific regions need particular attention. Increasing longitudinal connectivity stands out as a measure with the potential to increase species' resilience to the several threats affecting them, and it should be coupled with additional efforts to reduce water pollution, control alien species and effectively manage fishing.
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Affiliation(s)
- Maria João Costa
- Forest Research Centre, School of Agriculture, University of Lisbon Tapada da Ajuda, 1349-017 Lisboa, Portugal
| | - Gonçalo Duarte
- Forest Research Centre, School of Agriculture, University of Lisbon Tapada da Ajuda, 1349-017 Lisboa, Portugal.
| | - Pedro Segurado
- Forest Research Centre, School of Agriculture, University of Lisbon Tapada da Ajuda, 1349-017 Lisboa, Portugal
| | - Paulo Branco
- Forest Research Centre, School of Agriculture, University of Lisbon Tapada da Ajuda, 1349-017 Lisboa, Portugal
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