The theoretical foundations for size spectrum models of fish communities

Canadian Journal of Fisheries and Aquatic Sciences, Journal Year: 2015, Volume and Issue: 73(4), P. 575 - 588

Published: Nov. 23, 2015

Size spectrum models have emerged from 40 years of basic research on how body size determines individual physiology and structures marine communities. They are based commonly accepted assumptions a low parameter set, making them easy to deploy for strategic ecosystem-oriented impact assessment fisheries. We describe the fundamental concepts in size-based about food encounter bioenergetics budget individuals. Within general framework, three model types that differ their degree complexity: food-web, trait-based, community models. demonstrate differences between through examples response fishing dynamic behavior. review implementations important variations concerning functional response, whether growth is food-dependent or fixed, density dependence imposed system. Finally, we discuss challenges promising directions.

Language: Английский

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Disentangling diverse responses to climate change among global marine ecosystem models

Progress In Oceanography, Journal Year: 2021, Volume and Issue: 198, P. 102659 - 102659

Published: Aug. 9, 2021

Climate change is warming the ocean and impacting lower trophic level (LTL) organisms. Marine ecosystem models can provide estimates of how these changes will propagate to larger animals impact societal services such as fisheries, but at present vary widely. A better understanding what drives this inter-model variation improve our ability project fisheries other into future, while also helping identify uncertainties in process understanding. Here, we explore mechanisms that underlie diversity responses temperature LTLs eight global marine from Fisheries Ecosystem Model Intercomparison Project (FishMIP). Temperature LTL impacts on total consumer biomass structure (defined relative small large organism biomass) were isolated using a comparative experimental protocol. Total model varied between −35% +3% response warming, -17% +15% changes. There was little consensus about spatial redistribution or balance organisms (ecosystem structure) an depending choice forcing terms. Overall, climate are well approximated by sum impacts, indicating absence nonlinear interaction models' drivers. Our results highlight lack theoretical clarity represent fundamental ecological mechanisms, most importantly scale individual level, need understand two-way coupling consumers. We finish identifying future research needs strengthen modelling projections impacts.

Language: Английский

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Modeling What We Sample and Sampling What We Model: Challenges for Zooplankton Model Assessment

Frontiers in Marine Science, Journal Year: 2017, Volume and Issue: 4

Published: March 21, 2017

Zooplankton are the intermediate trophic level between phytoplankton and fish, an important component of carbon nutrient cycles, accounting for a large proportion energy transfer to pelagic fishes deep ocean. Given zooplankton's importance, models need adequately represent zooplankton dynamics. A major obstacle, though, is lack model assessment. Here we try stimulate assessment in by filling three gaps. The first that many observationalists unfamiliar with biogeochemical, ecosystem, size-based individual-based have functional groups, so describe their primary uses how each typically represents zooplankton. second gap modelers unaware data available, unaccustomed different sampling systems, main platforms discuss strengths weaknesses Filling these gaps our understanding observations provides necessary context address last – blueprint We detail two ways biomass/abundance can be used assess models: wrangling transforms more similar output; observation transform outputs like observations. hope this review will encourage greater ultimately improve representation

Language: Английский

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Bottom-up drivers of global patterns of demersal, forage, and pelagic fishes

Progress In Oceanography, Journal Year: 2019, Volume and Issue: 176, P. 102124 - 102124

Published: June 17, 2019

Language: Английский

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Advancing Global Ecological Modeling Capabilities to Simulate Future Trajectories of Change in Marine Ecosystems

Frontiers in Marine Science, Journal Year: 2020, Volume and Issue: 7

Published: Oct. 16, 2020

Considerable effort is being deployed to predict the impacts of climate change and anthropogenic activities on ocean's biophysical environment, biodiversity, natural resources better understand how marine ecosystems provided services humans are likely explore alternative pathways options. We present an updated version EcoOcean (v2), a spatial-temporal ecosystem modelling complex global ocean that spans food-web dynamics from primary producers top predators. Advancements include enhanced ability reproduce by linking species productivity, distributions, trophic interactions worldwide fisheries. The platform used simulate past future scenarios change, where we quantify configurations ecological model, responses climate-change scenarios, additional fishing. Climate-change obtained two Earth-System Models (ESMs, GFDL-ESM2M IPSL-CMA5-LR) contrasting emission (RCPs 2.6 8.5) for historical (1950-2005) (2006-2100) periods. Standardized indicators biomasses selected groups compare simulations. Results show trajectories sensitive EcoOcean, yield moderate differences when looking at larger groups. Ecological also environmental drivers ESM outputs RCPs, spatial variability more severe changes IPSL RCP 8.5 used. Under non-fishing configuration, organisms decreasing trends, while smaller mixed or increasing results. Fishing intensifies negative effects predicted again stronger under 8.5, which results in biomass declines already losing dampened positive those increasing. Several win become losers combined impacts, only few (small benthopelagic fish cephalopods) projected cumulative impacts. v2 can contribute quantification impact assessments multiple stressors plausible ocean-based solutions prevent, mitigate adapt change.

Language: Английский

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