River Research and Applications最新文献

{"title":"Limitations of Non‐Volitional Upstream Passage for Alewife (Alosa pseudoharengus) and Blueback Herring (Alosa aestivalis)","authors":"C. Ryan Hill, Antóin M. O'Sullivan, J. Derek Hogan, R. Allen Curry, Tommi Linnansaari, Philip M. Harrison","doi":"10.1002/rra.4372","DOIUrl":"https://doi.org/10.1002/rra.4372","url":null,"abstract":"We used PIT telemetry (<jats:italic>n</jats:italic> = 10,292 fish tagged) to evaluate upstream passage at a non‐volitional fishway (trap, lift, and truck) that passed approximately 10‐million river herring (alewife <jats:italic>Alosa pseudoharengus</jats:italic> and blueback herring <jats:italic>A</jats:italic>. <jats:italic>aestivalis</jats:italic>) around the lowermost dam in the Wolastoq/Saint John River, NB between 2020 and 2023. Between 26% and 62% of tagged fish reached the fishway crowding pool, while less than 14% were detected passing upstream. River herring experienced considerable passage delays (median = 3 days) after reaching the crowder entrance. The probability of passing on the date of first detection was only 10%, and it was positively correlated with the rate of fishway operation (i.e., fish lifts/unit time). The rate and probability of passage were greater for alewife than blueback herring and increased with total length for both species. Collectively, our results suggest that passage efficiency and duration were limited by the movement capacity and operation frequency of the fishway, and potentially the (high) number of fish attempting to pass at a given time. Ultimately, if the design and operation of non‐volitional fishways do not accommodate the size and behavior (i.e., schooling density and migration time) of target populations, our results indicate that potential consequences may include passage delays, reductions in passage efficiency, and selective pressures (e.g., size and species) on target populations.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":"6 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142224415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating UAV‐Based Topographic and Geomorphic Analysis for the Development of River Rehabilitation Plans in Semi‐Urban Settings","authors":"Dipro Sarkar, Rajiv Sinha","doi":"10.1002/rra.4371","DOIUrl":"https://doi.org/10.1002/rra.4371","url":null,"abstract":"Several rivers across the world face multiple threats from natural as well as human‐induced alterations in hydrology and morphology over time. Researchers have proposed several measures to instigate a healthier response by river rehabilitation or rejuvenation (depending on the condition of the river) to mitigate the impacts of causal factors. Investigating the causal factors of degradation is highly dependent on historical data, the availability of which depends on multiple considerations and is sometimes difficult to obtain, especially for a small river. A range of rehabilitation options have been explored by researchers among which geomorphology‐based approaches have gained importance as they are based on process‐based understanding and aim to reconstruct the river form for improving the river status. This paper introduces a novel method that uses very high‐resolution UAV data to analyze the topography and geomorphology of a small monsoon‐fed Sakri River in Central India. We aim to understand the anthropogenic factors responsible for its degradation with a particular focus on siltation and propose a river rejuvenation plan by creating the baseline data. The Sakri River supports 23 villages and a small town called Kawardha. The river presently has scanty surface flow and is unable to sustain the community. We mapped the entire river course using a UAV and identified 118 problematic sites, including 68 interventions along the 50 km stretch of the river. We have identified siltation as the primary problem at most sites caused by poorly designed interventions and a reduction in flow. We divided the river into 17 reaches and classified them into different states of criticality based on the identified problems and accumulated sediment volume behind the interventions. We have estimated a sizable volume of siltation within the 17 reaches as 0.5 million m<jats:sup>3</jats:sup>. Our analysis led to the development of a process response system that describes the various factors responsible for the degradation of the Sakri River and has important implications for designing mitigation strategies. Our recommendations for remedial measures are based on careful evaluation of the efficacy of each intervention and we have suggested their renovation or removal. We have also suggested reach‐specific solutions such as canal lining, river training, channel alignment, and river bank protection to be implemented.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":"5 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"If a fish comes out of the river and speaks, we should believe it: South African perspective on fish kills","authors":"Matthew J. Burnett, Gordon C. O'Brien, Andrew Blackmore, Melissa Wade, Colleen T. Downs","doi":"10.1002/rra.4359","DOIUrl":"https://doi.org/10.1002/rra.4359","url":null,"abstract":"In South Africa, fish kill events are increasing in frequency because of multiple stressors associated with managing natural resources. Despite the ecosystem services associated with fish, South Africa's progressive legislation towards environmental protection seems to negate the management of fish kills. In this study, we provide an overview of reports and regulations associated with acute pollution spills resulting in fish kill events in South Africa. In addition, we highlight the implication of these using a fish kill event from 2019 on the Msunduzi River, South Africa, as a case study. The fish kill on the Msunduzi River showed a decline in relative abundance by up to 41%, and its ecological condition was already impaired by poor management. The poor condition of the Msunduzi River has jeopardised the recovery of the fish populations, and intervention is needed to restore the fish population that includes species red‐listed as vulnerable by the International Union for the Conservation of Nature. We found that despite the severity of fish kills and the detriment to the fish fauna, including near‐threatened species, there is a general apathy, incapacity and lack of knowledge on managing fish kills in South Africa. In addition, although several legislated Acts have good intentions for protecting nature, they do not align and show that a fish kill is an afterthought rather than a need to prevent. Poor management practices have exacerbated this in an already stressed state from excessive use of environmental water. As a way forward, the alignment of the various Acts associated with various ministerial departments in South Africa is needed so that better protection of the environment may occur. Finally, we argue that the African proverb ‘<jats:italic>If the fish comes out of the river to tell you that the crocodile has one eye, you should believe it</jats:italic>’ is not considered when managing water resources and that with the present ecological state and water resource use there may be no fish to ‘come out of the water’ warning us that our water is unsafe even for human consumption and use.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":"24 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Timing is everything: Rethinking flexible hydropower operations for the economy and environment","authors":"Sarah Pfeifle, Katie Kennedy, Richard Palmer","doi":"10.1002/rra.4370","DOIUrl":"https://doi.org/10.1002/rra.4370","url":null,"abstract":"Hydropower facilities can alter river flow regimes, leading to ecological degradation and conflicts between revenue generation and ecological objectives. This study develops a new and unique framework (FREE—Flexible Releases for Economics and the Environment) for hydropower management that uses operational flexibility to balance economic and ecological objectives that are, respectively, maximized through unrestricted hydropeaking and maintaining natural flows. FREE integrates flexibility by permitting reservoir releases to deviate from inflows when power generation is most economically valuable. Operational flexibility is characterized by the magnitude and frequency of deviations from an inflow‐equals‐outflow (IEO) regime and is applied seasonally to reflect varying economic and ecological needs throughout the year. FREE is implemented using an optimization model applied to three hydropeaking facilities on the mainstem Connecticut River that are currently in a relicensing process. Estimated impacts of operational flexibility are quantified on annual and seasonal scales, with economic goals measured by power and revenue, and ecological goals by a proxy measure: the Richard‐Baker flashiness (RBF) index. To explore operational flexibility, two inflow regimes are investigated: existing inflows, which are altered by upstream hydropower operations, and estimated unaltered inflows. FREE was presented to interested parties engaged in the Connecticut River relicensing process, where it was applied in collaborative negotiations designed to develop integrated, dynamic, economically viable, and ecologically supportive hydropower operations. Trade‐offs between estimated revenue generation and RBF, as applicable to these interested parties, were presented along a Pareto frontier.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":"57 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effectiveness of spawning substrate enhancement for adfluvial fish in a regulated sub‐Arctic river","authors":"M. Miller, C. Stevens, M. S. Poesch","doi":"10.1002/rra.4358","DOIUrl":"https://doi.org/10.1002/rra.4358","url":null,"abstract":"Initial observations of egg mortality downstream of a hydroelectric facility on the Yellowknife River in the Northwest Territories prompted the investigation of habitat use by adfluvial lake trout (<jats:italic>Salvelinus namaycush</jats:italic>), lake whitefish (<jats:italic>Coregonus clupeaformis</jats:italic>), and cisco (<jats:italic>Coregonus artedi</jats:italic>). It was conducted to meet regulatory requirements under the Fisheries Act (1985) for the facility and was focused on results from annual snorkel surveys completed from 2016 to 2019. The design principles of the installed habitat were based on habitat rehabilitation projects for anadromous salmonids in rivers, artificial spawning reefs constructed in lakes for lacustrine populations of lake trout, and lake whitefish and the 2016 study results. The evaluation of the installed habitat was based on results from snorkel surveys that collected data on egg density and survival using 1 m<jats:sup>2</jats:sup> plots on both natural and artificially enhanced substrates. Three years of postenhancement monitoring indicated higher egg densities and a greater proportion of live eggs in the artificially enhanced habitat compared to the natural habitat, with more pronounced trends observed for coregonids (lake whitefish and cisco) compared to lake trout. These findings suggest that habitat enhancement has the potential to enhance juvenile recruitment for adfluvial fish. A critical factor in the design was ensuring the substrate composition provided adequate interstitial spaces for egg development and protection. This study represents the first documented attempt at habitat improvement in a regulated sub‐Arctic river in Canada. The results and design principles for the installed habitat offer a valuable framework for new or existing development projects in Northern Canada that require conservation actions to maintain fisheries productivity.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":"41 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The developing flood rich period: Science evidence and policy evolution for England. Is it time for place‐based socio‐ecological solutions?","authors":"Malcolm Newson, John Lewin","doi":"10.1002/rra.4363","DOIUrl":"https://doi.org/10.1002/rra.4363","url":null,"abstract":"Flood‐related policies for England are reviewed, updating needs in the light of recent flood‐rich decades and in recognition of future climate trends. This review updates one we published in 2021—a significant year for extreme floods in Europe that were part of a continuing trend; governments now require fast‐track adaptation and resilience policies. Currently, the event signals that increasing spatial and temporal variability of impacts are insufficiently incorporated in hazard/risk assessments. We advocate a transformative policy change towards place‐based strategies, based on the fast‐emerging evidence from three sciences: hydroclimatology, hydrology and hydromorphology. It is vital that policy actions recognise factors such as atmospheric rivers, surface water flooding, and the role of eroded and transported sediments in localised hazards and risks. Located vulnerabilities require local strategies. Attribution of extreme events to climate change, and the recognition and specification of genuinely vulnerable sites, need further refinement and extension into public decision making. Risk assessment needs reform, both from science but also for institutions and individuals, with accompanying reform of flood risk management expenditure. Data analysis of rainfall and river flows need more disciplined clarity; standard sets are needed together with their variable spatial/temporal application. We further recognise sediment hazards (and other entrained debris spread in flood flows) as new and important components for the located risk of present and emerging ‘hot spots’.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":"15 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Logjams in a mountain stream network: Patterns, biogeomorphic associations, and anthropogenic impacts","authors":"Piotr Cienciala, Andrew D. Nelson, Andrew D. Haas","doi":"10.1002/rra.4340","DOIUrl":"https://doi.org/10.1002/rra.4340","url":null,"abstract":"Logjams, in‐channel accumulations of downed wood, play important roles governing biophysical processes in river ecosystems. In this study conducted in the mountainous inland Pacific Northwest, we leveraged a basin‐scale inventory to carry out a comprehensive analysis of logjam frequency, volume, and their associations with a suite of biophysical landscape characteristics and anthropogenic influences. We complemented this analysis with one that relies on the concept of process domains. We found that logjam frequency increased with drainage area up to ~10–30 km<jats:sup>2</jats:sup> and declined thereafter, while the mean jam volume steadily increased downstream up to the area of &gt;300 km<jats:sup>2</jats:sup>. Combined, these variables yielded a nonlinear downstream pattern of large wood storage in jams, peaking at drainage areas of ~10–100 km<jats:sup>2</jats:sup>. Logjam characteristics were associated with multiple predictors, used as proxies for biogeomorphic processes relevant for large wood supply and redistribution: bank erosion, landslides, avulsions, wood availability in riparian forest, and wood transport. Additionally, anthropogenic disturbances were inferred to strongly influence logjam‐forming processes in the study basin. A riprapped forest road disrupted a process chain responsible for large wood supply, wherein erosion undercuts slope toe, ultimately triggering landslides. Timber harvest influenced large wood supply by reducing forest biomass. Overall, these findings contribute to improved understanding of logjams: they provide insight into the complex suite of interacting natural and anthropogenic factors which, by regulating large wood inputs and redistribution, generate a basin‐scale pattern in jam frequency and volume. We believe that our study will be useful in informing river management and restoration practices.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":"24 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal alterations of hydro power: Modelling the effect on growth of juvenile salmonids","authors":"Jan Henning L'Abée‐Lund, Harald Sægrov, Helge Skoglund, Ola Ugedal, Leif Asbjørn Vøllestad","doi":"10.1002/rra.4364","DOIUrl":"https://doi.org/10.1002/rra.4364","url":null,"abstract":"Hydropower (HP) has become the most important renewable energy source worldwide during the last century. However, the impacts on aquatic ecosystems may be considerable. In the Northern Hemisphere, salmonid fishes are often affected by hydropower‐related temperature alterations. As their metabolic processes are entirely dependent on water temperature, they are strongly affected when the HP development reduces the water temperature during summer by extracting water from below the thermocline of upstream reservoirs. We investigated juvenile growth of Atlantic salmon <jats:italic>Salmo salar</jats:italic> and brown trout <jats:italic>S. trutta</jats:italic> in six Norwegian rivers where hydropower has considerably reduced the water temperature during summer. We used observed mass of 1+ juveniles sampled upstream and downstream the tailrace of the hydropower plant and compared these with simulated mass of 1+ juveniles based on daily recorded water temperatures and a bioenergetics model. Establishment of reservoirs have led to reduced growth of juveniles of both species on river reaches downstream HP tailraces. The hydropower development significantly altered the temperature regimes with the downstream reaches having lower temperatures than upstream reaches. Both observed and predicted masses of 1+ juveniles of both species were also lower downstream than upstream. Predicted mass were more similar to the observed mass for Atlantic salmon than for brown trout, indicating that the bioenergetics model for brown trout is not optimal.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":"32 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing natural and human‐induced river corridor changes using object‐based image analysis (Orljava River, Croatia)","authors":"Katarina Pavlek, Mateo Gašparović, Ronald E. Poeppl","doi":"10.1002/rra.4369","DOIUrl":"https://doi.org/10.1002/rra.4369","url":null,"abstract":"This study employs object‐based image analysis to investigate land cover dynamics and channel changes in the managed corridor of the Orljava River following anthropogenic vegetation removal and a flood event. By classifying RGB and near‐infrared (NIR) images from the decade 2011–2021, five land cover classes within the river corridor were mapped: water, bare soil, sparse vegetation, dense vegetation, and shadows. A digital surface model generated from the images was used to differentiate between bare river channel units (river sediments) and bare soil in the floodplain, as well as to identify high vegetation, while agricultural land was classified manually. The study identified two main phases of river corridor changes, driven by a significant flood event in 2014. In the period 2011–2014, which includes the flood event, a substantial increase in the areas covered by water and river sediments was observed. The most notable decrease was in the bare soil class (90%), which primarily covered riverbanks and adjacent areas in 2011 after vegetation removal. In addition, the formation of large in‐channel bars due to sediment accumulation and significant channel migration was recorded. In the second phase (2014–2021), lower discharges facilitated gradual channel recovery, characterized by channel narrowing and an increase in dense and high vegetation. This study demonstrates the high reliability of object‐based classification in mapping river corridor units using optical photogrammetric data. Furthermore, it highlights the deficiencies in inadequate river management practices that led to considerable bank erosion and a loss of agricultural land.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":"45 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Muskrat (Ondatra zibethicus) predation on unionid mussels in the Salmon and Little Salmon rivers in northern New York","authors":"John E. Cooper","doi":"10.1002/rra.4368","DOIUrl":"https://doi.org/10.1002/rra.4368","url":null,"abstract":"Muskrat (<jats:italic>Ondatra zibethicus</jats:italic>) predation on unionid mussels has been documented since the late 1800s. More recent studies have examined size‐specific predation and potential effects of predation on mussel populations. This study was part of a larger endeavor that examined the effects of dam removal in the Salmon and Little Salmon rivers in northern New York. Muskrat middens were searched for from 2005 through 2012 and all mussel shells were identified, measured, and evaluated for evidence of muskrat predation. Ten species of consumed mussels were collected from 37 middens. Three species of living mussels that were in low abundance were not found in middens. Distribution of middens was uneven in both rivers and few middens were used in more than 1 year. Muskrats did not consume mussels &lt;37 mm shell length in the Salmon River (SR) and &lt;28 mm in the Little Salmon River (LSR). Shell length distribution of living mussels was similar to that of mussels in middens. Shell length of living SR mussels (based on mean ranks) were significantly longer than living mussels in the LSR as were consumed mussels. Size‐selection may be indicated for <jats:italic>Elliptio complanata</jats:italic> and <jats:italic>Lampsilis radiata</jats:italic> but relative abundance might also be a factor. Dry empty shell weight and thickness were not significantly correlated to percent predation marks. The muskrat population in these rivers could be small as few middens were used in more than 1 year and there was no evidence of muskrat trapping. If so, muskrat predation would have a limited effect on the unionid population.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":"3 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142185816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}