Experimental evidence for recovery of mercury-contaminated fish populations

Nature, Journal Year: 2021, Volume and Issue: 601(7891), P. 74 - 78

Published: Dec. 15, 2021

Anthropogenic releases of mercury (Hg)1-3 are a human health issue4 because the potent toxicant methylmercury (MeHg), formed primarily by microbial methylation inorganic Hg in aquatic ecosystems, bioaccumulates to high concentrations fish consumed humans5,6. Predicting efficacy pollution controls on MeHg is complex many factors influence production and bioaccumulation MeHg7-9. Here we conducted 15-year whole-ecosystem, single-factor experiment determine magnitude timing reductions following additions boreal lake its watershed. During seven-year addition phase, applied enriched isotopes increase local wet deposition rates fivefold. The became increasingly incorporated into food web as MeHg, predominantly from most those watershed remained there. Thereafter, isotopic were stopped, resulting an approximately 100% reduction loading lake. concentration labelled quickly decreased up 91% lower trophic level organisms, initiating rapid decreases 38-76% large-bodied populations eight years. Although watersheds may not decline step with lowering rates, this clearly demonstrates that any loadings lakes, whether direct or runoff, will have immediate benefits consumers.

Language: Английский

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Global climate change and the Baltic Sea ecosystem: direct and indirect effects on species, communities and ecosystem functioning

Earth System Dynamics, Journal Year: 2022, Volume and Issue: 13(2), P. 711 - 747

Published: April 11, 2022

Abstract. Climate change has multiple effects on Baltic Sea species, communities and ecosystem functioning through changes in physical biogeochemical environmental characteristics of the sea. Associated indirect secondary species interactions, trophic dynamics function are expected to be significant. We review studies investigating species-, population- ecosystem-level abiotic factors that may due global climate change, such as temperature, salinity, oxygen, pH, nutrient levels, more food web processes, primarily based peer-reviewed literature published since 2010. For phytoplankton, clear symptoms prolongation growing season, evident can explained by warming, but otherwise vary from area area. Several modelling project a decrease phytoplankton bloom spring an increase cyanobacteria blooms summer. The associated N:P ratio contribute maintaining “vicious circle eutrophication”. However, uncertainties remain because some field claim have not increased experimental show responses salinity pH species. An riverine dissolved organic matter (DOM) also primary production, relative importance this process different sea areas is well known. Bacteria growth favoured increasing temperature DOM, complex microbial probable. Warming seawater speeds up zooplankton shortens time lag between peaks, which lead decreasing spring. In summer, shift towards smaller-sized decline marine copepod been projected. deep benthic communities, continued eutrophication promotes high sedimentation maintains good conditions for zoobenthos. If abatement proceeds, improving oxygen will first zoobenthos biomass, subsequent sedimenting disrupt pelagic–benthic coupling decreased biomass. shallower photic systems, heatwaves produce eutrophication-like effects, e.g. overgrowth bladderwrack epiphytes, cascade. declines, bladderwrack, eelgrass blue mussel decline. Freshwater vascular plants they cannot replace macroalgae rocky substrates. Consequently invertebrates fish benefiting macroalgal belts suffer. Climate-induced environment favour establishment non-indigenous potentially affecting Sea. As fish, continuing hypoxia projected keep cod stocks low, whereas sprat certain coastal fish. Regime shifts cascading observed both pelagic systems result several climatic acting synergistically. Knowledge gaps include projecting future level, stratification potential rate internal loading, under forcings. This weakens our ability how productivity, populations future. 3D models, models 2D distribution would benefit integration, progress slowed down scale problems inability consider interactions Experimental work should better integrated into empirical get comprehensive view bacteria addition, understand biodiversity Sea, emphasis placed shallow environments. fate depend various intertwined development society. probably delay tend its “novel” state. conclude reductions stronger driver than change. Such highlight studying interlinked socio-ecological system.

Language: Английский

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Temperature impacts on fish physiology and resource abundance lead to faster growth but smaller fish sizes and yields under warming

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(21), P. 6239 - 6253

Published: July 13, 2022

Resolving the combined effect of climate warming and exploitation in a food web context is key for predicting future biomass production, size-structure potential yields marine fishes. Previous studies based on mechanistic size-based models have found that bottom-up processes are important drivers fisheries yield changing climates. However, we know less about joint effects 'bottom-up' physiological temperature; how do temperature propagate from individual-level physiology through webs alter exploited species community? Here, assess species-resolved affected by both these pathways exploitation. We parameterize dynamic size spectrum model inspired offshore Baltic Sea web, investigate individual growth rates, size-structure, relative abundances warming. The magnitude projections regional coupled system RCA4-NEMO RCP 8.5 emission scenario, evaluate different scenarios dependence fish resource productivity. When accounting temperature-effects addition to basal productivity, projected size-at-age 2050 increases average all species, mainly young fish, compared without In contrast, decreases when affects dynamics only, decline largest fish. Faster rates due warming, however, not always translate larger yields, as lower carrying capacities with increasing tend result abundance hence spawning stock biomass. These results suggest understand global structure communities, direct metabolic indirect via resources must be accounted for.

Language: Английский

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Relationships of temperature and biodiversity with stability of natural aquatic food webs

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: June 14, 2023

Abstract Temperature and biodiversity changes occur in concert, but their joint effects on ecological stability of natural food webs are unknown. Here, we assess these relationships 19 planktonic webs. We estimate as structural (using the volume contraction rate) temporal variation species abundances). Warmer temperatures were associated with lower stability, while had no consistent either property. While richness was higher Simpson diversity stability. The responses linked to disproportionate contributions from two trophic groups (predators consumers), both synchrony all within web distinctive three (predators, consumers, producers). Our results suggest that, ecosystems, warmer can erode ecosystem may not have effects.

Language: Английский

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Temperature‐Dependence Assumptions Drive Projected Responses of Diverse Size‐Based Food Webs to Warming

Earth s Future, Journal Year: 2024, Volume and Issue: 12(3)

Published: March 1, 2024

Abstract Food web projections are critical for evaluating potential risks to ecosystems and fisheries under global warming. The temperature dependence of biological processes regional differences in food structure two important sources uncertainty variation climate forced fish communities, but we do not know their magnitude or relative contribution. Here systematically evaluated a range different assumptions about temperature‐dependence on rates, including size‐dependent effects, controlling intake, metabolism, non‐predation mortality fishes using species‐resolved size spectrum models that link individual‐level physiological population community dynamics. We simulated the effect warming size‐structured calibrated marine simplified trait‐based models. Higher intake warmed conditions increased total biomass, catches, mean body weight, these effects were offset by negative metabolism mortality, which combined resulted lower biomasses catches most webs. These enhanced when metabolic rates more than outcomes also sensitive dependency responses. Importantly, general patterns uniform across all webs—individual functional groups species within webs responded ways depending position its structure. Hence, caution is warranted generalizing because they mediated interactions. Uncertainty related ecological interactions will impact should be represented change projections.

Language: Английский

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Weight–Length Relationship Analysis Revealing the Impacts of Multiple Factors on Body Shape of Fish in China

Fishes, Journal Year: 2023, Volume and Issue: 8(5), P. 269 - 269

Published: May 19, 2023

The weight–length relationship (WLR) of fish is a crucial tool in biology research and has received extensive attention. However, growth influenced by many factors, the WLR also changes accordingly. Our aim was to investigate how body shape affected various factors analyzing existing parameters between length weight. We analyzed 198,354 specimens belonging 402 species 82 families China investigated change function their ecology. Herbivorous tended be shorter fatter than carnivorous fish, omnivorous fall somewhere between. This difference could due variations feeding habits availability food sources. Additionally, living lentic waters have compared those lotic waters. attributed differences swimming behavior these environments. Furthermore, our results showed that b value decreased as altitude increased, thinner longer lower oxygen temperature levels high-altitude Overall, study provides valuable insights into impact multiple on shape.

Language: Английский

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Ecological consequences of body size reduction under warming

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2029)

Published: Aug. 1, 2024

Body size reduction is a universal response to warming, but its ecological consequences across biological levels, from individuals ecosystems, remain poorly understood. Most processes scale with body size, and warming-induced changes in can therefore have important consequences. To understand these consequences, we propose unifying, hierarchical framework for the impacts of intraspecific reductions due thermal plasticity that explicitly builds on three key pathways: morphological constraints, bioenergetic constraints surface-to-volume ratio. Using this framework, synthesize at multiple levels organization. We outline how trait-based improve our understanding, detection generalization warming.

Language: Английский

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Optimal energy allocation trade‐off driven by size‐dependent physiological and demographic responses to warming

Ecology, Journal Year: 2022, Volume and Issue: 104(4)

Published: Dec. 24, 2022

Abstract Body size–dependent physiological effects of temperature influence individual growth, reproduction, and survival, which govern animal population responses to global warming. Considerable knowledge has been established on how such can affect growth size structure, but less is known their potential role in temperature‐driven adaptation life‐history traits. In this study, we ask warming affects the optimal allocation energy between reproduction disentangle underlying fitness trade‐offs. To end, develop a novel dynamic budget integral projection model (DEB–IPM), linking individuals' size‐ temperature‐dependent consumption maintenance via somatic size‐dependent emergent responses. At level, calculate long‐term rate (fitness) stable structure emerging from demographic processes. Applying an example pike ( Esox lucius ), find that decreases with Furthermore, demonstrate fecundity, survival contribute change allocation. Higher at low temperatures increases through small individuals larger individuals. contrast, high temperatures, increased favored because induces faster fecundity reduced higher mortality Reduced optimum leads further reductions body increasingly truncated Our study demonstrates how, by incorporating general mechanisms driving dependence traits, DEB–IPM framework useful for investigating size‐structured organisms

Language: Английский

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Potential impacts of ocean warming on the trophic control of a threatened marine ecosystem

Progress In Oceanography, Journal Year: 2023, Volume and Issue: 211, P. 102976 - 102976

Published: Jan. 25, 2023

Language: Английский

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Larger but younger fish when growth outpaces mortality in heated ecosystem

eLife, Journal Year: 2023, Volume and Issue: 12

Published: May 9, 2023

Ectotherms are predicted to ‘shrink’ with global warming, in line general growth models and the temperature-size rule (TSR), both predicting smaller adult sizes warming. However, they also predict faster juvenile rates thus larger size-at-age of young organisms. Hence, result warming on size-structure a population depends interplay between how mortality rate, juvenile- affected by Here, we use two-decade long time series biological samples from unique enclosed bay heated cooling water nearby nuclear power plant become 5–10 °C warmer than its reference area. We used growth-increment biochronologies (12,658 reconstructed length-at-age estimates 2426 individuals) quantify >20 years has body growth, size-at-age, catch size- age structure Eurasian perch ( Perca fluviatilis ). In area, were for all sizes, hence was ages, compared While higher (lowering mean 0.4 years), lead 2 cm size Differences size-spectrum exponent (describing abundance declines size) less clear statistically. Our analyses reveal that mortality, addition plastic size-responses, is key factor determining populations exposed Understanding mechanisms which affects critical impacts climate change ecological functions, interactions, dynamics.

Language: Английский

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