From Bacteria to Whales: Using Functional Size Spectra to Model Marine Ecosystems

Trends in Ecology & Evolution, Journal Year: 2017, Volume and Issue: 32(3), P. 174 - 186

Published: Jan. 19, 2017

Language: Английский

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Distinct phytoplankton size classes respond differently to biotic and abiotic factors

ISME Communications, Journal Year: 2025, Volume and Issue: 5(1)

Published: Jan. 1, 2025

Abstract The interplay between abiotic (resource supply, temperature) and biotic (grazing) factors determines growth loss processes in phytoplankton through resource competition trophic interactions, which are mediated by morphological traits like size. Here, we study the relative importance of grazers, water physics, chemistry on daily net accumulation rates (ARs) individual from natural communities, grouped into six size classes circa 10 to 500 μm. Using a Random Forest modelling approach 4 years data lake, find that temperature is generally pivotal control all ARs. At same time, nutrients light important for smallest largest classes. Mesozooplankton abundance key predictor AR small phytoplankton, with microzooplankton being middle-size range. In our data, large have different (seasonal) blooming patterns: forms favoured low grazing, high phosphorus levels. Larger show positive ARs at temperatures (being relatively insensitive zooplankton grazing). These results help us understand opportunities limitations using explain model responses environmental change.

Language: Английский

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Overcoming the Data Crisis in Biodiversity Conservation

Trends in Ecology & Evolution, Journal Year: 2018, Volume and Issue: 33(9), P. 676 - 688

Published: July 7, 2018

HighlightsDiagnosing the conservation status of many species is hampered by insufficient data. Modern computer-intensive fitting methods make it possible to merge mechanistic models and population data on well-studied indicator species, extending inferences we can about their data-limited relatives.Historically, assessments have used from one or create ad hoc proxy values for life-history traits relatives, but with modern Bayesian share information in a standardized, coherent way.Advances understanding community ecology evolution be incorporated into these as priors, statistical power even when are sparse.These advances offer new possibilities rigorous assessment protection populations that previously suffered policy gaps created data.AbstractHow track trends monitoring sparse? Population declines go undetected, despite ongoing threats. For example, only every 200 harvested monitored. This gap leads uncertainty seriousness hampers effective conservation. Collecting more important, also better use existing information. Prior knowledge physiology, life history, inform models. Additionally, multispecies models, shared among taxa based phylogenetic, spatial, temporal proximity. By exploiting generalities across evolutionary ecological characteristics within hierarchical fill crucial species' unparalleled quantitative rigor.

Language: Английский

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A trait-based approach to ocean ecology

ICES Journal of Marine Science, Journal Year: 2018, Volume and Issue: 75(6), P. 1849 - 1863

Published: June 20, 2018

Abstract Trait-based ecology merges evolutionary with classical population and community is a rapidly developing branch of ecology. It describes ecosystems as consisting individuals rather than species, characterizes by few key traits that are interrelated through trade-offs. The fundamental rationale the spatio-temporal distribution organisms their functional role in depend on taxonomical affiliation. approach respects interactions between individuals, not species or populations, trait-based models ecosystem structure emerges result environments, being prescribed. offers an alternative to species-centric approaches has potential describe complex simple ways assess effects environmental change function. Here, we components apply it model marine ecosystems. Our description illustrated multiple examples life ocean from unicellular plankton fish.

Language: Английский

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Bioaccumulation of methylmercury within the marine food web of the outer Bay of Fundy, Gulf of Maine

PLoS ONE, Journal Year: 2018, Volume and Issue: 13(7), P. e0197220 - e0197220

Published: July 16, 2018

Mercury and methylmercury were measured in seawater biota collected from the outer Bay of Fundy to better document mercury bioaccumulation a temperate marine food web. The size an organism, together with δ13 C δ15 N isotopes, interpret levels ranging microplankton (25μm) swordfish, dolphins whales. Levels no different depth not elevated relative upstream sources. values primary producers found be inadequate specify original energy source various faunas, however, there was reason separate web into benthic, demersal pelagic chains because phytoplankton has been documented almost exclusively fuel ecosystem. apparent abrupt increase content "seawater" phytoplankton, on wet weight basis, can explained environmental volume basis by exponential surface area smaller particles included determinations. This physical sorption process may important up macroplankton category dominated copepods according calculated biomagnification factors (BMF). rapid concentration, total mercury, between predominantly (<125μm) zooplankton categories is likely augmented gut microbe methylation. Further chain, trophic transfer dominates resulting greater than 10 Atlantic bluefin tuna, harbour porpoise, white-sided dolphin common thresher shark. power northern Gulf Maine ecosystem remarkably similar that tropical, subtropical, other arctic oceanic ecozones.

Language: Английский

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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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Fishing degrades size structure of coral reef fish communities

Global Change Biology, Journal Year: 2016, Volume and Issue: 23(3), P. 1009 - 1022

Published: Aug. 26, 2016

Fishing pressure on coral reef ecosystems has been frequently linked to reductions of large fishes and fish biomass. Associated impacts overall community structure are, however, less clear. In size-structured aquatic ecosystems, fishing are commonly quantified using size spectra, which describe the distribution individual body sizes within a community. We examined spectra biomass communities at 38 US-affiliated Pacific islands that ranged in human presence from near pristine population centers. Size 'steepened' steadily with increasing proximity market due reduction relative an increase dominance small fishes. Reef was substantially lower inhabited than uninhabited ones, even lowest levels presence. found populated exponents decreased (analogous steepening) linearly declining biomass, whereas there no relationship. were steeper regions low sea surface temperature but insensitive variation other environmental geomorphic covariates. contrast, highly sensitive oceanographic conditions, being influenced by both oceanic productivity temperature. Our results suggest may be more robust indicator reliable indicators exploitation across different compositions, drivers, fisheries types. Size-based approaches link directly functional properties communities, relatively abiotic biogeographic regions, offer great potential for developing our understanding ecosystems.

Language: Английский

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Pyramids and cascades: a synthesis of food chain functioning and stability

Ecology Letters, Journal Year: 2018, Volume and Issue: 22(2), P. 405 - 419

Published: Dec. 17, 2018

Abstract Food chain theory is one of the cornerstones ecology, providing many its basic predictions, such as biomass pyramids, trophic cascades and predator–prey oscillations. Yet, ninety years into this theory, conditions under which these patterns may occur persist in nature remain subject to debate. Rather than address each pattern isolation, we propose that they must be understood together, calling for synthesis a fragmented landscape theoretical empirical results. As first step, minimal combines long‐standing energetic dynamical approaches food chains. We chart predictions on concise map, where two main regimes emerge: across various functioning stability metrics, regime characterised by pyramidal other cascade patterns. The axes map combine key physiological ecological variables, metabolic rates self‐regulation. A quantitative comparison with data sheds light conflicting puzzles, from size spectra causes strength. conclude drawing systematic connections between existing chains, their stability, crucial step confronting real ecosystems.

Language: Английский

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Cell size as driver and sentinel of phytoplankton community structure and functioning

Functional Ecology, Journal Year: 2021, Volume and Issue: 36(2), P. 276 - 293

Published: Dec. 12, 2021

Abstract Body size is a decisive functional trait in many organisms, especially for phytoplankton, which span several orders of magnitude cell volume. Therefore, the analysis as driving species’ performance has received wide attention aquatic ecology, amended recent decades by studies documenting changes phytoplankton response to abiotic or biotic factors environment. We performed systematic literature review provide an overarching, partially quantitative synthesis driver and sentinel ecology. found consistent significant allometric relationships between sizes species (cellular rates carbon fixation, respiration exudation well resource affinities, uptake content). Size scaling became weaker, absent even negative when addressing C‐ volume‐specific growth. C‐specific photosynthesis population growth rate peaked at intermediate around 100 µm 3 . Additionally, we rich on changing warming, nutrients pollutants. Whereas small cells tended dominate under oligotrophic warm conditions, there are few notable exceptions, indicates that other environmental constraints alter this general trend. Grazing seems likely explanation, reviewed understand both how affects edibility structure grazing. Cell also predisposes strength outcome competitive interactions algal species. Finally, address community context, where size‐abundance describes composition thereby biodiversity assemblages. conclude (a) highly predictive metabolism cellular scale, with less strong nonlinear implications specific (b) suitable responses environments. A free Plain Language Summary can be within Supporting Information article.

Language: Английский

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The global ocean size spectrum from bacteria to whales

Science Advances, Journal Year: 2021, Volume and Issue: 7(46)

Published: Nov. 10, 2021

It has long been hypothesized that aquatic biomass is evenly distributed among logarithmic body mass size classes. Although this community structure observed regionally, mostly plankton groups, its generality never formally tested across all marine life over the global ocean, nor have impacts of humans on it globally assessed. Here, we bring together data at scale to test hypothesis from bacteria whales. We find within most order magnitude classes indeed remarkably constant, near 1 gigatonne (Gt) wet weight (1015 g), but and large mammals are markedly above below value, respectively. Furthermore, human appear significantly truncated upper one-third spectrum. This dramatic alteration what possibly life’s largest-scale regularity underscores extent activities.

Language: Английский

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