Geomorphic context in process‐based river restoration

River Research and Applications, Год журнала: 2024, Номер 40(3), С. 322 - 340

Опубликована: Янв. 2, 2024

Abstract Process‐based river restoration seeks to restore processes such as channel‐floodplain connectivity that create and maintain corridor functions. can fail produce the desired results if geomorphic context is not effectively incorporated into design. Geomorphic of a reach refers controls on contemporary form process. Controls at catchment‐ reach‐scale include geologic history, biophysical characteristics, legacies past human alterations, position within network, geometry, base level stability, disturbance regime, alterations corridor. We conceptualize reflecting interactions among fluxes material context. discuss how an understanding be used select approach provide examples achieve outcomes when considered. Within toolbox methods implement process‐based restoration, we differentiate alteration inputs through from and/or Historical, biotic, geologic/geomorphic, reference sites inform targets. Restoration strongly influenced by perceptions what appropriate achievable site diverse communities influencing may differ in their perceptions. Geomorphically based conceptual guidelines, River Styles Framework, effective platform for incorporating restoration.

Язык: Английский

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The potential for nature-based solutions to combat the freshwater biodiversity crisis

PLOS Water, Год журнала: 2023, Номер 2(6), С. e0000126 - e0000126

Опубликована: Июнь 8, 2023

Enthusiasm for and investments in nature-based solutions (NBS) as sustainable strategies climate adaptation infrastructure development is building among governments, the scientific community, engineering practitioners. This particularly true water security water-related risks. In a freshwater context, NBS may provide much-needed “win-wins” society environment that could benefit imperiled biodiversity. Such conservation benefits are urgently needed given ongoing biodiversity crisis, with declines species their habitats occurring at more than twice rate of marine or terrestrial systems. However, to make meaningful contributions safeguarding biodiversity, clear links must be established between applications priorities conservation. this paper, we link common six priority actions life by science n highlight research knowledge will necessary bring bear on crisis. particular, illustrate how can play direct role restoring degraded aquatic floodplain ecosystems, enhancing in-stream quality, improving hydrological connectivity ecosystems. System-level monitoring ensure deliver promised ecosystems species.

Язык: Английский

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Bending the curve of global freshwater biodiversity loss: what are the prospects?

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Год журнала: 2024, Номер unknown

Опубликована: Сен. 2, 2024

ABSTRACT Freshwater biodiversity conservation has received substantial attention in the scientific literature and is finally being recognized policy frameworks such as Global Biodiversity Framework its associated targets for 2030. This important progress. Nonetheless, freshwater species continue to be confronted with high levels of imperilment widespread ecosystem degradation. An Emergency Recovery Plan (ERP) proposed 2020 comprises six measures intended “bend curve” loss, if they are widely adopted adequately supported. We review evidence suggesting that combined intensity persistent emerging threats become so serious current projected efforts preserve, protect restore inland‐water ecosystems may insufficient avert losses coming decades. In particular, climate change, complex harmful impacts, will frustrate attempts prevent from already affected by multiple threats. Interactions among these limit recovery populations exacerbate declines resulting local or even global extinctions, especially low‐viability degraded fragmented ecosystems. addition impediments represented we identify several other areas where absolute scarcity fresh water, inadequate information predictive capacity, a failure mitigate anthropogenic stressors, liable set limits on biodiversity. Implementation ERP rapidly at scale through many dispersed actions focused regions intense threat, together an intensification ex‐situ efforts, necessary preserve native during increasingly uncertain climatic future which poorly understood, emergent interacting have more influential. But implementation must accompanied improve energy food security humans – without further compromising condition Unfortunately, political policies arrest environmental challenges change do not inspire confidence about possible success ERP. parts world, Anthropocene seems certain include extended periods uncontaminated surface runoff inevitably appropriated humans. Unless there step‐change societal awareness commitment biodiversity, established methods protecting bend curve enough continued degradation loss.

Язык: Английский

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Responses of multimetric indices to disturbance are affected by index construction features

Environmental Reviews, Год журнала: 2024, Номер 32(2), С. 278 - 293

Опубликована: Фев. 22, 2024

Multimetric indices (MMIs) are used worldwide to assess the ecological conditions of aquatic and terrestrial ecosystems. Different criteria approaches construct MMIs, resulting in widely different indices. Therefore, scientists, managers, policymakers sometimes question whether such MMIs useful for biomonitoring bioassessment programs. Crucial design issues programs include MMI responsiveness, bioindicator group used, survey design, field sampling methods, level taxonomic resolution, metric selection scoring, reference condition identification. We performed a meta-analysis on development applications analyze response disturbance factors determine degree which construction features influence their responsiveness anthropogenic disturbances. Web Science database find articles that applied an related values environmental stressor, we extracted data from 157 articles. random-effects modeling estimate overall effect responses subgroup analysis extent sizes varied as function features. found had major disturbance. The type, number metrics, ecosystem type were contributed more weakly size variance. general was little affected by group, criteria, or scoring method. These findings have important implications designing programs, including developing improving cost-effective biological indices, because they could enhance application protocols.

Язык: Английский

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Vegetation responses to large dam removal on the Elwha River, Washington, USA

Frontiers in Ecology and Evolution, Год журнала: 2024, Номер 12

Опубликована: Фев. 13, 2024

Large dam removal can trigger changes to physical and biological processes that influence vegetation dynamics in former reservoirs, along river corridors downstream of dams, at a river’s terminus deltas estuaries. We present the first comprehensive review response major fluvial disturbance caused by world’s largest removal. After being place for nearly century, two large dams were removed Elwha River, Washington, USA, between 2011 2014. The exposure, erosion, transport, deposition volumes sediment wood impounded behind created new surfaces where plant colonization growth have occurred. In exposed ~290 ha unvegetated distributed on three main landforms: valley walls, high terraces, dynamic floodplains. addition natural revegetation weed control seeding planting desirable plants influenced trajectories. early years following removal, ~20.5 Mt trapped eroded from reservoirs transported downstream. This pulse, combination with transport wood, led channel widening, an increase gravel bars, floodplain deposition. primary responses corridor reduction vegetated area associated establishment increased hydrochory, altered community composition bars Plant species diversity some segments. delta, creation ~26.8 land distribution intertidal water bodies. Vegetation colonized ~16.4 surfaces: mixed pioneer supratidal beach, mouth emergent marsh aquatic habitats. sediment-dominated opportunities growth, such as restored hydrochory anadromous fish passage delivery marine-derived nutrients may over time. Rapid landforms related pulse rate change is expected attenuate system adjusts flow regimes.

Язык: Английский

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A Watershed Moment for Western U.S. Dams

Water Resources Research, Год журнала: 2023, Номер 59(10)

Опубликована: Окт. 1, 2023

Abstract The summer of 2023 is a notable time for water‐resource management in the western United States: Glen Canyon Dam, on Colorado River, turns 60 years old while largest dam‐removal project history beginning Klamath River. This commentary discusses these events context changing paradigm dam and reservoir this region. Since era large building began to wane six decades ago, new challenges have arisen owing climate change, population increase, sedimentation, declining safety aging dams, more environmentally focused objectives. Today we also better understand dams' benefits, costs, environmental impacts, including some that were unforeseen took become apparent. Where dams unsafe, obsolete (e.g., due excessive sedimentation), uneconomical beyond saving, removal has common. science practice are accelerating rapidly, long‐term physical biological response studies now available. Removal four hydroelectric River will be larger complex than any previous removal. imminency reflects very different situation ago. Looking forward, States worldwide require continued collaboration innovative thinking meet wide range objectives manage water resources sustainably future generations.

Язык: Английский

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Dam removal enables diverse juvenile life histories to emerge in threatened salmonids repopulating a heterogeneous landscape

Frontiers in Ecology and Evolution, Год журнала: 2023, Номер 11

Опубликована: Июнь 2, 2023

Human stressors block, eliminate, and simplify habitat mosaics, eroding landscapes’ life history diversity thus biological resilience. One goal of restoration is to alleviate human that suppress diversity, but responses these efforts are still coming into focus. Here, we report emerging in threatened salmonids ( Oncorhynchus spp.) repopulating the recently undammed Elwha River (WA, United States) adjacent environmentally distinct tributaries. The ~20 km tributaries entered <1 apart, one had a colder stream temperature regime swifter waters due its high, snow-dominated elevation steep valley gradient (~3%), while other warmer slower because it drained lake, was at lower elevation, (~1.5%). Following 2012 removal Dam, tributaries’ generally became more abundant expressed diverse histories within among species. warmer, low-gradient tributary produced age-1+ coho salmon colder, steeper notably high abundance steelhead smolts 2020. Additionally, exiting were older possibly larger for their age class, emigrated ~25 days earlier, included age-0 Chinook larger. Also, assemblage composition varied years, with most species shifting between salmon, abundances increased patchy. These patterns consistent newly accessible, heterogeneous landscape generating against backdrop patchy recruitment as salmonids—some considerable hatchery-origin ancestry—repopulate an extirpated landscape. Overall, dam appears have promoted which may bolster resilience during era rapid environmental change portend positive outcomes upcoming removals similar goals.

Язык: Английский

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Dammed context: Community perspectives on ecosystem service changes following Poland's first dam removal

Land Degradation and Development, Год журнала: 2024, Номер 35(6), С. 2184 - 2200

Опубликована: Фев. 7, 2024

Abstract Decisions to build or remove dams and other large engineered hydraulic infrastructures are always entangled in social environmental impacts, which often evaluated formally through bureaucratic processes. In Europe dam removals relatively infrequent, even though extensive infrastructure has degraded biodiversity water quality. The Wilkówka southern Poland was required be removed rapidly, primarily due engineering failures during its construction. Using survey methods, we examine the local community's perceptions of net impacts removal. surveying opinions households, 62% respondents expressed that decisions about removal were taken without sufficient community consultation, 92% felt had been despite their opposition. Although built recently failed operate at design capacity, reported strong attachments services they perceived it provide, including supply, flood regulation cultural significance. spite possibility an disaster long‐term degradation, most surveyed households would have preferred renovated reconstructed. short, by but also officials as bringing a loss socially relevant ecosystem services, urgent need for regional national authorities. rapid attachment potential negative on environment attributable high expectations hydrological provide (water larger symbolic value infrastructural investment community). This work provides empirical demonstration importance understanding social, ecological technological context within decision‐making processes regarding removals, implications may improve planning implementation future projects.

Язык: Английский

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A review of adult salmon maximum swim performance.

Canadian Journal of Fisheries and Aquatic Sciences, Год журнала: 2024, Номер 81(9), С. 1174 - 1216

Опубликована: Фев. 15, 2024

Salmonids undertake long and strenuous migrations that require aerobic endurance anaerobic burst swimming. Anthropogenic activity natural disasters can make already challenging even more difficult. This reinvigorates a central question: what is the maximum swimming capacity of adult salmon species across environmental conditions? We synthesized literature on swim performance ( Oncorhynchus spp. Salmo salar) to unfold known about how biological (sex body size) physical (temperature) factors affect in salmon. Maximum swimming—bursting, jumping, leaping—are among least studied performances salmonids. Commonly, has been measured using flumes, but evidently faster wild than this set-up capture. show larger fish outswim smaller ones, thermal sensitivity differs inter-and -intra-specifically. Unresolved are temperatures, between males females maturity states. information be used inform exercise physiology research future management mitigation actions necessary conserve these iconic, economically valuable species.

Язык: Английский

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Initial responses of Chinook salmon (Oncorhynchus tshawytscha) and steelhead (Oncorhynchus mykiss) to removal of two dams on the Elwha River, Washington State, U.S.A.

Frontiers in Ecology and Evolution, Год журнала: 2024, Номер 12

Опубликована: Июль 17, 2024

Large dam removal is being used to restore river systems, but questions remain regarding their outcomes. We examine how the of two large dams in Elwha River, coupled with hatchery production and fishing closures, affected population attributes Chinook salmon ( Oncorhynchus tshawytscha ) steelhead O. mykiss ). Initial responses by returning adult was an increase number spatial extent natural origin fish. Although few naturally produced juvenile outmigrants were observed prior during removal, abundances increased three years after fish passage restored, suggesting that impacts due downstream sedimentation reduced. The demographics dominated production, while increases winter abundance included both natural-origin spawners. expansion upstream former sites predominantly also a “reawakening” summer part derived from up-river resident returned Upper Elwha. Our results showed combination habitat, hatchery, harvest actions can result positive for salmonid populations.

Язык: Английский

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