Metabolic plasticity can amplify ecosystem responses to global warming

Abstract Organisms have the capacity to alter their physiological response to warming through acclimation or adaptation, but empirical evidence for this metabolic plasticity across species within food webs is lacking, and a generalisable framework does not exist for modelling its ecosystem-level consequences. Here we show that the ability of organisms to raise their metabolic rate following chronic exposure to warming decreases with increasing body size. Chronic exposure to higher temperatures also increases the sensitivity of organisms to short-term warming, irrespective of their body size. A mathematical model parameterised with these findings shows that metabolic plasticity could account for an additional 60% of ecosystem energy flux with just +2 °C of warming. This could explain why ecosystem respiration continues to rise in long-term warming experiments and highlights the need to embed metabolic plasticity in predictive models of global warming impacts on ecosystems.

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Acute and chronic exposure to air pollution in relation with incidence, prevalence, severity and mortality of COVID-19: a rapid systematic review

Environmental Health ◽

10.1186/s12940-021-00714-1 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Patrick D. M. C. Katoto ◽

Amanda S. Brand ◽

Buket Bakan ◽

Paul Musa Obadia ◽

Carsi Kuhangana ◽

...

Keyword(s):

Air Pollution ◽

Chronic Exposure ◽

Ambient Air ◽

Short Term ◽

Incidence And Mortality ◽

Acute And Chronic Exposure ◽

Anthropogenic Pollutant ◽

Incident Cases ◽

Incidence Prevalence

Abstract Background Air pollution is one of the world’s leading mortality risk factors contributing to seven million deaths annually. COVID-19 pandemic has claimed about one million deaths in less than a year. However, it is unclear whether exposure to acute and chronic air pollution influences the COVID-19 epidemiologic curve. Methods We searched for relevant studies listed in six electronic databases between December 2019 and September 2020. We applied no language or publication status limits. Studies presented as original articles, studies that assessed risk, incidence, prevalence, or lethality of COVID-19 in relation with exposure to either short-term or long-term exposure to ambient air pollution were included. All patients regardless of age, sex and location diagnosed as having COVID-19 of any severity were taken into consideration. We synthesised results using harvest plots based on effect direction. Results Included studies were cross-sectional (n = 10), retrospective cohorts (n = 9), ecological (n = 6 of which two were time-series) and hypothesis (n = 1). Of these studies, 52 and 48% assessed the effect of short-term and long-term pollutant exposure, respectively and one evaluated both. Pollutants mostly studied were PM2.5 (64%), NO2 (50%), PM10 (43%) and O3 (29%) for acute effects and PM2.5 (85%), NO2 (39%) and O3 (23%) then PM10 (15%) for chronic effects. Most assessed COVID-19 outcomes were incidence and mortality rate. Acutely, pollutants independently associated with COVID-19 incidence and mortality were first PM2.5 then PM10, NO2 and O3 (only for incident cases). Chronically, similar relationships were found for PM2.5 and NO2. High overall risk of bias judgments (86 and 39% in short-term and long-term exposure studies, respectively) was predominantly due to a failure to adjust aggregated data for important confounders, and to a lesser extent because of a lack of comparative analysis. Conclusion The body of evidence indicates that both acute and chronic exposure to air pollution can affect COVID-19 epidemiology. The evidence is unclear for acute exposure due to a higher level of bias in existing studies as compared to moderate evidence with chronic exposure. Public health interventions that help minimize anthropogenic pollutant source and socio-economic injustice/disparities may reduce the planetary threat posed by both COVID-19 and air pollution pandemics.

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Impacts of long-term warming and enhanced nitrogen and sulfur deposition on carbon sink potential in a boreal peatland

10.5194/egusphere-egu21-1210 ◽

2021 ◽

Author(s):

Tuula Larmola ◽

Liisa Maanavilja ◽

Heikki Kiheri ◽

Mats Nilsson ◽

Matthias Peichl

Keyword(s):

Global Change ◽

Wet Deposition ◽

Carbon Sink ◽

Ecosystem Respiration ◽

N Deposition ◽

Ecosystem Responses ◽

Gross Photosynthesis ◽

Poor Fen ◽

The Individual

In order to assess peatland carbon sink potential under multiple global change perturbations, we examined the individual and combined effects of long-term warming and enhanced nitrogen (N) and sulfur (S) deposition on ecosystem CO2 exchange at one of the longest-running experiments on peatlands, Deger&#246; Stormyr poor fen, Sweden. The site has been treated with NH4NO3 (15 times ambient annual wet deposition), Na2SO4 (6 times ambient annual wet deposition) and elevated temperature (air +3.6 C) for 23 years. Gross photosynthesis, ecosystem respiration and net CO2 exchange were measured weekly during June-August using chambers. After 23 years, two of the experimental perturbations: N addition and warming individually reduced net CO2 uptake potential down to 0.3-0.4 fold compared to the control mainly due to lower gross photosynthesis. Under S only treatment ecosystem CO2 fluxes were largely unaltered. In contrast, the combination of S and N deposition and warming led to a more pronounced effect and close to zero net CO2 uptake potential or net C source. Our study emphasizes the value of the long-term multifactor experiments in examining the ecosystem responses: simultaneous perturbations can have nonadditive interactions that cannot be predicted based on individual responses and thus, must be studied in combination when evaluating feedback mechanisms to ecosystem C sink potential under global change.

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The longer the worse: a combined proteomic and targeted study of the long-term versus short-term effects of silver nanoparticles on macrophages

Environmental Science Nano ◽

10.1039/c9en01329f ◽

2020 ◽

Vol 7 (7) ◽

pp. 2032-2046

Author(s):

Bastien Dalzon ◽

Catherine Aude-Garcia ◽

Hélène Diemer ◽

Joanna Bons ◽

Caroline Marie-Desvergne ◽

...

Keyword(s):

Silver Nanoparticles ◽

Chronic Exposure ◽

Acute Exposure ◽

Short Term ◽

Short Term Effects

At equal cumulated dose, a chronic exposure to silver nanoparticles produces more effects on macrophages than an acute exposure.

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The dilemma of controlling cultural eutrophication of lakes

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2012.1032 ◽

2012 ◽

Vol 279 (1746) ◽

pp. 4322-4333 ◽

Cited By ~ 318

Author(s):

David W. Schindler

Keyword(s):

Large Scale ◽

Ecosystem Processes ◽

Nutrient Fluxes ◽

Nutrient Cycles ◽

Case Histories ◽

Short Term ◽

Ecosystem Responses ◽

Lake Recovery ◽

Recent Claim

The management of eutrophication has been impeded by reliance on short-term experimental additions of nutrients to bottles and mesocosms. These measures of proximate nutrient limitation fail to account for the gradual changes in biogeochemical nutrient cycles and nutrient fluxes from sediments, and succession of communities that are important components of whole-ecosystem responses. Erroneous assumptions about ecosystem processes and lack of accounting for hysteresis during lake recovery have further confused management of eutrophication. I conclude that long-term, whole-ecosystem experiments and case histories of lake recovery provide the only reliable evidence for policies to reduce eutrophication. The only method that has had proven success in reducing the eutrophication of lakes is reducing input of phosphorus. There are no case histories or long-term ecosystem-scale experiments to support recent claims that to reduce eutrophication of lakes, nitrogen must be controlled instead of or in addition to phosphorus. Before expensive policies to reduce nitrogen input are implemented, they require ecosystem-scale verification. The recent claim that the ‘phosphorus paradigm’ for recovering lakes from eutrophication has been ‘eroded’ has no basis. Instead, the case for phosphorus control has been strengthened by numerous case histories and large-scale experiments spanning several decades.

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HISTORY, POLITICS, AND CLAIMS OF MAN-MADE GLOBAL WARMING

Social Philosophy and Policy ◽

10.1017/s0265052509090232 ◽

2009 ◽

Vol 26 (2) ◽

pp. 231-271

Author(s):

John David Lewis

Keyword(s):

Global Warming ◽

Environmental Protection Agency ◽

Fossil Fuels ◽

Global Scale ◽

The Political ◽

Economic Decline ◽

Protection Agency ◽

Short Term ◽

Scientific Support

Claims that a man-made global warming catastrophe is imminent have two major aspects: the scientific support offered for the claims, and the political proposals brought forth in response to the claims. The central questions are whether non-scientists should accept the claims themselves as true, and whether they should support the political proposals attached to them. Predictions of a coming disaster are shown to be a-historical in both the long term and the short term, to involve shifting predictions that are contrary to evidence, and to be opposed by many scientists. The political proposals to alleviate this alleged problem—especially plans by the U.S. Environmental Protection Agency—are shown to offer no alternative to fossil fuels, and to portend a major economic decline and permanent losses of liberty. The anthropogenic global warming claims are largely motivated not by science, but by a desire for socialist intervention on a national and a global scale. Neither the claims to an impending climate catastrophe nor the political proposals attached to those claims should be accepted.

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On the Identification and Characterization of Drought and Aridity in Postglacial Paleoenvironmental Records from the Northern Great Plains

Géographie physique et Quaternaire ◽

10.7202/009108ar ◽

2004 ◽

Vol 56 (2-3) ◽

pp. 229-246 ◽

Cited By ~ 8

Author(s):

Alwynne B. Beaudoin

Keyword(s):

Global Warming ◽

High Resolution ◽

Great Plains ◽

Northern Great Plains ◽

Short Term ◽

Instrumental Data ◽

Proxy Records ◽

Identification And Characterization

Abstract The Northern Great Plains region is especially sensitive to drought and is likely to be even more drought-prone under projected global warming. Drought has been invoked as an explanatory factor for changes seen in postglacial paleoenvironmental records. These proxy records may extend drought history derived from instrumental data. Moreover, in the last decade, some paleoenvironmental studies have been expressly undertaken for the examination of long-term drought history. Nevertheless, few such studies explicitly define drought. This makes it difficult to compare results or to understand what the results mean in terms of the operational drought definitions that are used in resource management. Operational drought is defined as usually short-term; longer sustained dry intervals reflect a shift to aridity. Therefore, high resolution paleoenvironmental proxies (annual or subdecadal) are best for the investigation of drought history. Such proxies include tree rings and some lake records. However, most lake-based records are sampled at lower resolution (decadal or subcentury) and are therefore providing aridity signals.

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Technical note: On comparing greenhouse gas emission metrics

Atmospheric Chemistry and Physics ◽

10.5194/acp-21-4699-2021 ◽

2021 ◽

Vol 21 (6) ◽

pp. 4699-4708

Author(s):

Ian Enting ◽

Nathan Clisby

Keyword(s):

Global Warming ◽

Greenhouse Gas ◽

Global Warming Potential ◽

Radiative Forcing ◽

Greenhouse Gas Emission ◽

Technical Note ◽

Short Term ◽

Rates Of Change

Abstract. Many metrics for comparing greenhouse gas emissions can be expressed as an instantaneous global warming potential multiplied by the ratio of airborne fractions calculated in various ways. The forcing equivalent index (FEI) provides a specification for equal radiative forcing at all times at the expense of generally precluding point-by-point equivalence over time. The FEI can be expressed in terms of asymptotic airborne fractions for exponentially growing emissions. This provides a reference against which other metrics can be compared. Four other equivalence metrics are evaluated in terms of how closely they match the timescale dependence of FEI, with methane referenced to carbon dioxide used as an example. The 100-year global warming potential overestimates the long-term role of methane, while metrics based on rates of change overestimate the short-term contribution. A recently proposed metric based on differences between methane emissions 20 years apart provides a good compromise. Analysis of the timescale dependence of metrics expressed as Laplace transforms leads to an alternative metric that gives closer agreement with FEI at the expense of considering methane over longer time periods. The short-term behaviour, which is important when metrics are used for emissions trading, is illustrated with simple examples for the four metrics.

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The Short-Term Cooling but Long-Term Global Warming Due to Biomass Burning

Journal of Climate ◽

10.1175/1520-0442(2004)017<2909:tscblg>2.0.co;2 ◽

2004 ◽

Vol 17 (15) ◽

pp. 2909-2926 ◽

Cited By ~ 58

Author(s):

Mark Z. Jacobson

Keyword(s):

Global Warming ◽

Biomass Burning ◽

Short Term

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Ecosystem consequences of multi-trait response to environmental changes in Japanese medaka, Oryzias latipes

Conservation Physiology ◽

10.1093/conphys/coaa011 ◽

2020 ◽

Vol 8 (1) ◽

Cited By ~ 1

Author(s):

Beatriz Diaz Pauli ◽

Eric Edeline ◽

Charlotte Evangelista

Keyword(s):

Body Size ◽

Feeding Rate ◽

Oryzias Latipes ◽

Ecosystem Processes ◽

Nutrient Concentrations ◽

Ammonium Excretion ◽

Short Term ◽

Mean And Variance ◽

Stoichiometric Traits

Abstract Intraspecific trait variation has large effects on the ecosystem and is greatly affected by human activities. To date, most studies focused on single-trait analyses, while considering multiple traits is expected to better predict how an individual interacts with its environment. Here, we used a mesocosm experiment with fish Oryzias latipes to test whether individual growth, boldness and functional traits (feeding rate and stoichiometric traits) formed one functional pace-of-life syndrome (POLS). We then tested the effects of among-individual mean and variance of fish functional POLSs within mesocosms on invertebrate community (e.g. zoobenthos and zooplankton abundances) and ecosystem processes (e.g. ecosystem metabolism, algae stock, nutrient concentrations). Stoichiometric traits correlated with somatic growth and behaviours, forming two independent functional POLS (i.e. two major covariance axes). Mean values of the first syndrome were sex- and environment-dependent and were associated with (i) long-term (10 generations; 4 years) selection for small or large body size resulting in contrasting life histories and (ii) short-term (6 weeks) effects of experimental treatments on resource availability (through manipulation of light intensity and interspecific competition). Specifically, females and individuals from populations selected for a small body size presented fast functional POLS with faster growth rate, higher carbon body content and lower boldness. Individuals exposed to low resources (low light and high competition) displayed a slow functional POLS. Higher mesocosm mean and variance values in the second functional POLS (i.e. high feeding rate, high carbon:nitrogen body ratio, low ammonium excretion rate) were associated to decreased prey abundances, but did not affect any of the ecosystem processes. We highlighted the presence of functional multi-trait covariation in medaka, which were affected by sex, long-term selection history and short-term environmental conditions, that ultimately had cascading ecological consequences. We stressed the need for applying this approach to better predict ecosystem response to anthropogenic global changes.

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