1
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Atkinson A, Rossberg AG, Gaedke U, Sprules G, Heneghan RF, Batziakas S, Grigoratou M, Fileman E, Schmidt K, Frangoulis C. Steeper size spectra with decreasing phytoplankton biomass indicate strong trophic amplification and future fish declines. Nat Commun 2024; 15:381. [PMID: 38195697 PMCID: PMC10776571 DOI: 10.1038/s41467-023-44406-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 12/12/2023] [Indexed: 01/11/2024] Open
Abstract
Under climate change, model ensembles suggest that declines in phytoplankton biomass amplify into greater reductions at higher trophic levels, with serious implications for fisheries and carbon storage. However, the extent and mechanisms of this trophic amplification vary greatly among models, and validation is problematic. In situ size spectra offer a novel alternative, comparing biomass of small and larger organisms to quantify the net efficiency of energy transfer through natural food webs that are already challenged with multiple climate change stressors. Our global compilation of pelagic size spectrum slopes supports trophic amplification empirically, independently from model simulations. Thus, even a modest (16%) decline in phytoplankton this century would magnify into a 38% decline in supportable biomass of fish within the intensively-fished mid-latitude ocean. We also show that this amplification stems not from thermal controls on consumers, but mainly from temperature or nutrient controls that structure the phytoplankton baseline of the food web. The lack of evidence for direct thermal effects on size structure contrasts with most current thinking, based often on more acute stress experiments or shorter-timescale responses. Our synthesis of size spectra integrates these short-term dynamics, revealing the net efficiency of food webs acclimating and adapting to climatic stressors.
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Affiliation(s)
- Angus Atkinson
- Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth, PL13DH, UK.
| | - Axel G Rossberg
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Ursula Gaedke
- Institute of Biochemistry and Biology, University of Potsdam, 14469, Potsdam, Germany
| | - Gary Sprules
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Rd. N., Mississauga, ON, L5L 1C6, Canada
| | - Ryan F Heneghan
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Stratos Batziakas
- Hellenic Centre for Marine Research, Former U.S. Base at Gournes, P.O. Box 2214, Heraklion GR-71003, Crete, Greece
| | | | - Elaine Fileman
- Plymouth Marine Laboratory, Prospect Place, The Hoe, Plymouth, PL13DH, UK
| | - Katrin Schmidt
- University of Plymouth, School of Geography, Earth and Environmental Sciences, Plymouth, PL4 8AA, UK
| | - Constantin Frangoulis
- Hellenic Centre for Marine Research, Former U.S. Base at Gournes, P.O. Box 2214, Heraklion GR-71003, Crete, Greece
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2
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O'Brien DA, Deb S, Gal G, Thackeray SJ, Dutta PS, Matsuzaki SIS, May L, Clements CF. Early warning signals have limited applicability to empirical lake data. Nat Commun 2023; 14:7942. [PMID: 38040724 PMCID: PMC10692136 DOI: 10.1038/s41467-023-43744-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 11/17/2023] [Indexed: 12/03/2023] Open
Abstract
Research aimed at identifying indicators of persistent abrupt shifts in ecological communities, a.k.a regime shifts, has led to the development of a suite of early warning signals (EWSs). As these often perform inaccurately when applied to real-world observational data, it remains unclear whether critical transitions are the dominant mechanism of regime shifts and, if so, which EWS methods can predict them. Here, using multi-trophic planktonic data on multiple lakes from around the world, we classify both lake dynamics and the reliability of classic and second generation EWSs methods to predict whole-ecosystem change. We find few instances of critical transitions, with different trophic levels often expressing different forms of abrupt change. The ability to predict this change is highly processing dependant, with most indicators not performing better than chance, multivariate EWSs being weakly superior to univariate, and a recent machine learning model performing poorly. Our results suggest that predictive ecology should start to move away from the concept of critical transitions, developing methods suitable for predicting resilience loss not limited to the strict bounds of bifurcation theory.
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Affiliation(s)
- Duncan A O'Brien
- School of Biological Sciences, University of Bristol, Bristol, BS8 1TQ, UK.
| | - Smita Deb
- Department of Mathematics, Indian Institute of Technology Ropar, Rupnagar, Punjab, 140001, India
| | - Gideon Gal
- Kinneret Limnological Laboratory, Israel Oceanographic & Limnological Research, PO Box 447, Migdal, Israel
| | - Stephen J Thackeray
- Lake Ecosystems Group, UK Centre for Ecology & Hydrology, Bailrigg, Lancaster, UK
| | - Partha S Dutta
- Department of Mathematics, Indian Institute of Technology Ropar, Rupnagar, Punjab, 140001, India
| | - Shin-Ichiro S Matsuzaki
- Biodiversity Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan
| | - Linda May
- UK Centre for Ecology & Hydrology, Bush Estate, Penicuik, Midlothian, EH26 OQB, UK
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3
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Audzijonyte A, Delius GW, Stuart-Smith RD, Novaglio C, Edgar GJ, Barrett NS, Blanchard JL. Changes in sea floor productivity are crucial to understanding the impact of climate change in temperate coastal ecosystems according to a new size-based model. PLoS Biol 2023; 21:e3002392. [PMID: 38079442 PMCID: PMC10712853 DOI: 10.1371/journal.pbio.3002392] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 10/19/2023] [Indexed: 12/18/2023] Open
Abstract
The multifaceted effects of climate change on physical and biogeochemical processes are rapidly altering marine ecosystems but often are considered in isolation, leaving our understanding of interactions between these drivers of ecosystem change relatively poor. This is particularly true for shallow coastal ecosystems, which are fuelled by a combination of distinct pelagic and benthic energy pathways that may respond to climate change in fundamentally distinct ways. The fish production supported by these systems is likely to be impacted by climate change differently to those of offshore and shelf ecosystems, which have relatively simpler food webs and mostly lack benthic primary production sources. We developed a novel, multispecies size spectrum model for shallow coastal reefs, specifically designed to simulate potential interactive outcomes of changing benthic and pelagic energy inputs and temperatures and calculate the relative importance of these variables for the fish community. Our model, calibrated using field data from an extensive temperate reef monitoring program, predicts that changes in resource levels will have much stronger impacts on fish biomass and yields than changes driven by physiological responses to temperature. Under increased plankton abundance, species in all fish trophic groups were predicted to increase in biomass, average size, and yields. By contrast, changes in benthic resources produced variable responses across fish trophic groups. Increased benthic resources led to increasing benthivorous and piscivorous fish biomasses, yields, and mean body sizes, but biomass decreases among herbivore and planktivore species. When resource changes were combined with warming seas, physiological responses generally decreased species' biomass and yields. Our results suggest that understanding changes in benthic production and its implications for coastal fisheries should be a priority research area. Our modified size spectrum model provides a framework for further study of benthic and pelagic energy pathways that can be easily adapted to other ecosystems.
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Affiliation(s)
- Asta Audzijonyte
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia
- Centre for Marine Socioecology, University of Tasmania, Hobart, Australia
| | - Gustav W. Delius
- Department of Mathematics, University of York, York, United Kingdom
| | - Rick D. Stuart-Smith
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia
| | - Camilla Novaglio
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia
- Centre for Marine Socioecology, University of Tasmania, Hobart, Australia
| | - Graham J. Edgar
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia
| | - Neville S. Barrett
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia
| | - Julia L. Blanchard
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia
- Centre for Marine Socioecology, University of Tasmania, Hobart, Australia
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4
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Khaliq I, Biber M, E. Bowler D, Hof C. Global change impacts on bird biodiversity in South Asia: potential effects of future land-use and climate change on avian species richness in Pakistan. PeerJ 2023; 11:e16212. [PMID: 37818326 PMCID: PMC10561643 DOI: 10.7717/peerj.16212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 09/10/2023] [Indexed: 10/12/2023] Open
Abstract
Evaluating the impact of future changes in land-use and climate on species communities, especially species richness, is one of the most important challenges of current research in ecology and conservation. The impact of environmental changes on species richness depends on its sensitivity (i.e., how strongly a given level of change influences the ecological community) and its exposure (i.e., the amount of change that occurs). To examine the sensitivity, exposure, and potential impact of future environmental conditions on bird communities, we compiled data on bird species richness for Pakistan-a neglected region in macro- or country-scale studies. Since bird species richness strongly varies across seasons due to the seasonal occurrence of migratory species in winter, we compared both wintering (migratory plus resident species) and breeding (resident species only) bird richness. We found breeding and wintering species richness to be sensitive to temperature, precipitation and rainfed cropland by being positively related to these factors. Exposure varied regionally, with projected temperature changes being most profound in northern regions while the strongest projected precipitation changes occurred in central and southern regions. The projected impact of future environmental change were highly heterogeneous across the country and differed between the wintering and breeding communities. Overall, the most negatively impacted region was projected to be the Khyber Pakhtunkha province in the North of Pakistan, due to reductions in precipitation and rainfed cropland, resulting in a projected negative impact, especially on wintering species richness. By highlighting the regional and seasonal bird communities most at risk, our findings provide useful information for policy makers to help devise new policies for mitigating negative impacts of future environmental changes on birds within Pakistan.
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Affiliation(s)
- Imran Khaliq
- Department of Aquatic Ecology, Swiss Federal Institute of Aquatic Science and Technology (EAWAG), Dubendorf, Zurich, Switzerland
- Department of Zoology, Government (Defunct) College, Dera Ghazi Khan, Punjab, Pakistan
| | - Matthias Biber
- Terrestrial Ecology Research Group, Department for Life Science Systems, School of Life Sciences, Technical University of Munich, Freising, Munich, Germany
| | - Diana E. Bowler
- UK Centre for Ecology & Hydrology Maclean Building, Wallingford, Oxford, United Kingdom
| | - Christian Hof
- Terrestrial Ecology Research Group, Department for Life Science Systems, School of Life Sciences, Technical University of Munich, Freising, Munich, Germany
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5
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Merz E, Saberski E, Gilarranz LJ, Isles PDF, Sugihara G, Berger C, Pomati F. Disruption of ecological networks in lakes by climate change and nutrient fluctuations. NATURE CLIMATE CHANGE 2023; 13:389-396. [PMID: 37038592 PMCID: PMC10079529 DOI: 10.1038/s41558-023-01615-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 01/24/2023] [Indexed: 06/19/2023]
Abstract
Climate change interacts with local processes to threaten biodiversity by disrupting the complex network of ecological interactions. While changes in network interactions drastically affect ecosystems, how ecological networks respond to climate change, in particular warming and nutrient supply fluctuations, is largely unknown. Here, using an equation-free modelling approach on monthly plankton community data in ten Swiss lakes, we show that the number and strength of plankton community interactions fluctuate and respond nonlinearly to water temperature and phosphorus. While lakes show system-specific responses, warming generally reduces network interactions, particularly under high phosphate levels. This network reorganization shifts trophic control of food webs, leading to consumers being controlled by resources. Small grazers and cyanobacteria emerge as sensitive indicators of changes in plankton networks. By exposing the outcomes of a complex interplay between environmental drivers, our results provide tools for studying and advancing our understanding of how climate change impacts entire ecological communities.
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Affiliation(s)
- Ewa Merz
- Department of Aquatic Ecology, Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Erik Saberski
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA USA
| | - Luis J. Gilarranz
- Department of Aquatic Ecology, Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Peter D. F. Isles
- Vermont Department of Environmental Conservation, Montpelier, VT USA
| | - George Sugihara
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA USA
| | - Christine Berger
- Stadt Zuerich, Wasserversorgung, Qualitaetsueberwachung, Zuerich, Switzerland
| | - Francesco Pomati
- Department of Aquatic Ecology, Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
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6
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O'Brien DA, Gal G, Thackeray SJ, Matsuzaki SS, Clements CF. Planktonic functional diversity changes in synchrony with lake ecosystem state. GLOBAL CHANGE BIOLOGY 2023; 29:686-701. [PMID: 36370051 PMCID: PMC10100413 DOI: 10.1111/gcb.16485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 08/23/2022] [Accepted: 10/07/2022] [Indexed: 06/16/2023]
Abstract
Managing ecosystems to effectively preserve function and services requires reliable tools that can infer changes in the stability and dynamics of a system. Conceptually, functional diversity (FD) appears as a sensitive and viable monitoring metric stemming from suggestions that FD is a universally important measure of biodiversity and has a mechanistic influence on ecological processes. It is however unclear whether changes in FD consistently occur prior to state responses or vice versa, with no current work on the temporal relationship between FD and state to support a transition towards trait-based indicators. There is consequently a knowledge gap regarding when functioning changes relative to biodiversity change and where FD change falls in that sequence. We therefore examine the lagged relationship between planktonic FD and abundance-based metrics of system state (e.g. biomass) across five highly monitored lake communities using both correlation and cutting edge non-linear empirical dynamic modelling approaches. Overall, phytoplankton and zooplankton FD display synchrony with lake state but each lake is idiosyncratic in the strength of relationship. It is therefore unlikely that changes in plankton FD are identifiable before changes in more easily collected abundance metrics. These results highlight the power of empirical dynamic modelling in disentangling time lagged relationships in complex multivariate ecosystems, but suggest that FD cannot be generically viable as an early indicator. Individual lakes therefore require consideration of their specific context and any interpretation of FD across systems requires caution. However, FD still retains value as an alternative state measure or a trait representation of biodiversity when considered at the system level.
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Affiliation(s)
| | - Gideon Gal
- Kinneret Limnological LaboratoryIsrael Oceanographic and Limnological ResearchMigdalIsrael
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7
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Protistan epibionts affect prey selectivity patterns and vulnerability to predation in a cyclopoid copepod. Sci Rep 2022; 12:22631. [PMID: 36587046 PMCID: PMC9805443 DOI: 10.1038/s41598-022-26004-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 12/07/2022] [Indexed: 01/01/2023] Open
Abstract
Colonisation of crustacean zooplankton with ciliate epibionts is widespread in freshwater and marine environments. However, the ecology of such association are little studied as yet. The occurrence of ciliate epibionts on copepods and the preference towards this association with different life stages of Mesocyclops were studied from winter to spring. Relative susceptibility of zooplankton species was evaluated by analysing the epibiont colonies and zooids and relate this to the surface area of the host. The maximum epibiont infestation per unit body surface area was recorded on copepodites followed by copepod nauplii rather than other zooplankton species, whereas the rotifer Asplanchna was never affected. Influence of climatic factors such as temperature on the colonisation of epibionts on basibionts was found significant. In winter (November to February) samples, copepods were infested by autotrophic epibionts whereas in late spring and early summer (March-April) heterotrophic protists (peritrichian ciliates) were the sole epibionts on copepods. We conducted experiments in the laboratory on prey selection pattern of predators by direct visual and video-graphic observations of various events (encounter, attack, capture, ingestion, prey escape) during predation by infested and uninfested copepodites and adults of Mesocyclops. Postencounter the attack probability was significantly lower in infested than in uninfested copepods. The present paper reports on substrate preference by epibionts and their impacts in food rich and food scarce environments. Furthermore, major environmental interactions were studied with the reproductive phenology of copepods with respect to epibionts and the cause and effect of long term association of epibionts with copepods need to be addressed.
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8
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González-Olalla JM, Medina-Sánchez JM, Carrillo P. Fluctuation at High Temperature Combined with Nutrients Alters the Thermal Dependence of Phytoplankton. MICROBIAL ECOLOGY 2022; 83:555-567. [PMID: 34145482 DOI: 10.1007/s00248-021-01787-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 06/01/2021] [Indexed: 06/12/2023]
Abstract
The Metabolic Theory of Ecology (MTE) predicts that the temperature increases exert a common effect on organisms stimulating metabolic rates, this being stronger for a heterotrophic than for an autotrophic metabolism. However, no available studies within the MTE framework have focused on organisms' response under fluctuation at high temperature interacting with factors such as nutrient availability, or how this interaction could affect the coexistence between mixotrophic and strict autotrophic phytoplankton. Hence, we assess how the phytoplankton metabolism and species composition are affected under scenarios of high temperature and fluctuation at high temperature, and how nutrients alter the direction and magnitude of such impact. For that, we use a mixed culture composed of two phytoplankton species: a strict autotrophic species and a mixotrophic species. Our results indicate that, in agreement with the MTE, only fluctuation at high temperature treatment registered a greater activation energy (Ea) value for respiration than for primary production and stimulated mixotrophic over strict autotrophic species abundance compared to control treatment. Remarkably, fluctuation at high temperature had a strong negative impact on the total abundance of the mixed-culture. The interaction between nutrient enrichment and fluctuation at high temperature increased abundance of the strict autotrophic species and overall species abundance, and led to Ea values that were higher in primary production than in respiration. Changes in community composition, enhanced by nutrient enrichment, could be behind this response, which can have implications in ecosystem functioning in a changing world.
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Affiliation(s)
- Juan Manuel González-Olalla
- University Institute of Water Research, University of Granada, C/Ramón y Cajal, 4, 18071, Granada, Spain
- Department of Ecology, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
| | - Juan Manuel Medina-Sánchez
- Department of Ecology, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain.
| | - Presentación Carrillo
- University Institute of Water Research, University of Granada, C/Ramón y Cajal, 4, 18071, Granada, Spain
- Department of Ecology, Faculty of Sciences, University of Granada, Campus Fuentenueva s/n, 18071, Granada, Spain
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9
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Hillebrand H, Acevedo‐Trejos E, Moorthi SD, Ryabov A, Striebel M, Thomas PK, Schneider M. Cell size as driver and sentinel of phytoplankton community structure and functioning. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13986] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Helmut Hillebrand
- Institute for Chemistry and Biology of Marine Environments [ICBM] Plankton Ecology Lab Carl‐von‐Ossietzky University Oldenburg Wilhelmshaven Germany
- Helmholtz‐Institute for Functional Marine Biodiversity at the University of Oldenburg [HIFMB] Oldenburg Germany
- Alfred Wegener Institute Helmholtz‐Centre for Polar and Marine Research [AWI] Bremerhaven Germany
| | - Esteban Acevedo‐Trejos
- Earth Surface Process Modelling Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences Potsdam Germany
| | - Stefanie D. Moorthi
- Institute for Chemistry and Biology of Marine Environments [ICBM] Plankton Ecology Lab Carl‐von‐Ossietzky University Oldenburg Wilhelmshaven Germany
| | - Alexey Ryabov
- Institute for Chemistry and Biology of Marine Environments [ICBM] Mathematical Modelling Carl‐von‐Ossietzky University Oldenburg Oldenburg Germany
- Institute of Forest Growth and Computer Science Technische Universität Dresden Tharandt Germany
| | - Maren Striebel
- Institute for Chemistry and Biology of Marine Environments [ICBM] Plankton Ecology Lab Carl‐von‐Ossietzky University Oldenburg Wilhelmshaven Germany
| | - Patrick K. Thomas
- Institute for Chemistry and Biology of Marine Environments [ICBM] Plankton Ecology Lab Carl‐von‐Ossietzky University Oldenburg Wilhelmshaven Germany
| | - Marie‐Luise Schneider
- Institute for Chemistry and Biology of Marine Environments [ICBM] Plankton Ecology Lab Carl‐von‐Ossietzky University Oldenburg Wilhelmshaven Germany
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10
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Zhang H, Zhang P, Wang H, García Molinos J, Hansson LA, He L, Zhang M, Xu J. Synergistic effects of warming and eutrophication alert zooplankton predator-prey interactions along the benthic-pelagic interface. GLOBAL CHANGE BIOLOGY 2021; 27:5907-5919. [PMID: 34390088 DOI: 10.1111/gcb.15838] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 08/03/2021] [Indexed: 06/13/2023]
Abstract
Contemporary evidence suggests that climate change and other co-occurring large-scale environmental changes, such as eutrophication, will have a considerable impact on aquatic communities. However, the interactions of these environmental changes on trophic interactions among zooplankton remain largely unknown. Here we present results of a mesocosm experiment examining how a couple of zooplankton predator and prey taxa with different life-history strategies respond to the combined effect of an increase in temperature (4.5°C) and in eutrophication (phosphorus addition), during the crucial recruiting and growing season. We show that the addition of phosphorus alone significantly weakened the top-down effects by the cyclopoid copepod predators on their rotifer prey. In contrast, warming strengthened the top-down effects from the predator, leading to a reduction in the abundance of the rotifer prey. These effects of warming were enhanced by phosphorus addition. Together, our results demonstrate that warming made plankton prey organisms more susceptible to top-down effects from predators, but reduced their sensitivity to nutrient enrichment. In terms of the phenological effects, warming advanced the termination of diapause for both rotifers and cyclopoid copepods by about 2 weeks, but these temporal shifts, akin for both groups, resulted in no apparent trophic mismatch. Hence, from a future perspective, cyclopoid copepods are likely to benefit more from the combination of nutrient enrichment and climate warming to the detriment of their rotifer prey.
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Affiliation(s)
- Huan Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Peiyu Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Huan Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Jorge García Molinos
- Arctic Research Center, Hokkaido University, Sapporo, Japan
- Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan
| | | | - Liang He
- Key Laboratory of Poyang Lake Environment and Resource Utilization of Ministry of Education, Nanchang University, Nanchang, China
| | - Min Zhang
- College of Fisheries, Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Huazhong Agricultural University, Wuhan, China
| | - Jun Xu
- State Key Laboratory of Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
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11
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Fontana S, Rasmann S, de Bello F, Pomati F, Moretti M. Reconciling trait based perspectives along a trait-integration continuum. Ecology 2021; 102:e03472. [PMID: 34260747 DOI: 10.1002/ecy.3472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 04/09/2021] [Accepted: 05/18/2021] [Indexed: 11/08/2022]
Abstract
Trait based ecology has developed fast in the last decades, aiming to both explain mechanisms of community assembly, and predict patterns in nature, such as the effects of biodiversity shifts on key ecosystem processes. This body of work has stimulated the development of several conceptual frameworks and analytical methods, as well as the production of trait databases covering a growing number of taxa and organizational levels (from individuals to guilds). However, this breeding ground of novel concepts and tools currently lacks a general and coherent framework, under which functional traits can help ecologists organize their research aims, and serve as the common currency to unify several scientific disciplines. Specifically, we see a need to bridge the gaps between community ecology, ecosystem ecology, and evolutionary biology, in order to address the most pressing environmental issues of our time. To achieve this integration goal, we define a trait-integration continuum, which reconciles alternative trait definitions and approaches in ecology. This continuum outlines a coherent progression of biological scales, along which traits interact and hierarchically integrate from genetic information, to whole organism fitness-related traits, to trait syndromes and functional groups. Our conceptual scheme proposes that lower-level trait integration is closer to the inference of ecoevolutionary mechanisms determining population and community properties, whereas higher-level trait integration is most suited to the prediction of ecosystem processes. Within these two extremes, trait integration varies on a continuous scale, which relates directly to the inductive-deductive loop that should characterize the scientific method. With our proposed framework, we aim to facilitate scientists in contextualising their research based on the trait-integration levels that matter most to their specific goals. Explicitly acknowledging the existence of a trait-integration continuum is a promising way for framing the appropriate questions, thus obtaining reliable answers and results that are comparable across studies and disciplines.
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Affiliation(s)
- Simone Fontana
- Biodiversity and Conservation Biology, Swiss Federal Research Institute WSL, Zürcherstrasse 111, Birmensdorf, 8903, Switzerland.,Nature Conservation and Landscape Ecology, University of Freiburg, Tennenbacher Straße 4, Freiburg, 79106, Germany
| | - Sergio Rasmann
- Laboratory of Functional Ecology, Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, Neuchâtel, 2000, Switzerland
| | - Francesco de Bello
- Department of Botany, Faculty of Sciences, University of South Bohemia, Na Zlate Stoce 1, České Budějovice, 370 05, Czech Republic.,Desertification Research Centre (CIDE-CSIC), Carretera Moncada-Náquera, Km 4,5, Moncada (Valencia), 46113, Spain
| | - Francesco Pomati
- Department of Aquatic Ecology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, Dübendorf, 8600, Switzerland
| | - Marco Moretti
- Biodiversity and Conservation Biology, Swiss Federal Research Institute WSL, Zürcherstrasse 111, Birmensdorf, 8903, Switzerland
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12
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Suikkanen S, Uusitalo L, Lehtinen S, Lehtiniemi M, Kauppila P, Mäkinen K, Kuosa H. Diazotrophic cyanobacteria in planktonic food webs. FOOD WEBS 2021. [DOI: 10.1016/j.fooweb.2021.e00202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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13
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Manna V, De Vittor C, Giani M, Del Negro P, Celussi M. Long-term patterns and drivers of microbial organic matter utilization in the northernmost basin of the Mediterranean Sea. MARINE ENVIRONMENTAL RESEARCH 2021; 164:105245. [PMID: 33429217 DOI: 10.1016/j.marenvres.2020.105245] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 11/17/2020] [Accepted: 12/26/2020] [Indexed: 06/12/2023]
Abstract
Marine heterotrophic prokaryotes degrade, transform, and utilize half of the organic matter (OM) produced by photosynthesis, either in dissolved or particulate form. Microbial metabolic rates are affected by a plethora of different factors, spanning from environmental variables to OM composition. To tease apart the environmental drivers underlying the observed organic matter utilization rates, we analysed a 21 year-long time series from the Gulf of Trieste (NE Adriatic Sea). Heterotrophic carbon production (HCP) time series analysis highlighted a long-term structure made up by three periods of coherent observations (1999-2007; 2008-2011; 2012-2019), shared also by OM concentration time series. Temporal patterns of HCP drivers, extracted with a random forest approach, demonstrated that a period of high salinity anomalies (2002-2008) was the main driver of this structure. The reduced river runoff and the consequent depletion of river-borne inorganic nutrients induced a long-term Chl a decline (2006-2009), followed by a steady increase until 2014. HCP driving features over the three periods substantially changed in their seasonal patterns, suggesting that the years following the draught period represented a transition between two long-term regimes. Overall, temperature and particulate organic carbon concentration were the main factors driving HCP rates. The emergence of these variables highlighted the strong control exerted by the temperature-substrate co-limitation on microbial growth. Further exploration revealed that HCP rates did not follow the Arrhenius' linear response to temperature between 2008 and 2011, demonstrating that microbial growth was substrate-limited following the draught event. By teasing apart the environmental drivers of microbial growth on a long-term perspective, we demonstrated that a substantial change happened in the biogeochemistry of one of the most productive areas of the Mediterranean Sea. As planktonic microbes are the foundation of marine ecosystems, understanding their past dynamics may help to explain present and future changes.
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Affiliation(s)
- Vincenzo Manna
- National Institute of Oceanography and Applied Geophysics - OGS, Trieste, Italy; University of Trieste, Department of Life Sciences, Trieste, Italy.
| | - Cinzia De Vittor
- National Institute of Oceanography and Applied Geophysics - OGS, Trieste, Italy
| | - Michele Giani
- National Institute of Oceanography and Applied Geophysics - OGS, Trieste, Italy
| | - Paola Del Negro
- National Institute of Oceanography and Applied Geophysics - OGS, Trieste, Italy
| | - Mauro Celussi
- National Institute of Oceanography and Applied Geophysics - OGS, Trieste, Italy
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Phytoplankton Community Response to Nutrients, Temperatures, and a Heat Wave in Shallow Lakes: An Experimental Approach. WATER 2020. [DOI: 10.3390/w12123394] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Phytoplankton usually responds directly and fast to environmental fluctuations, making them useful indicators of lake ecosystem changes caused by various stressors. Here, we examined the phytoplankton community composition before, during, and after a simulated 1-month heat wave in a mesocosm facility in Silkeborg, Denmark. The experiment was conducted over three contrasting temperature scenarios (ambient (A0), Intergovernmental Panel on Climate Change A2 scenario (circa +3 °C, A2) and A2+ %50 (circa +4.5 °C, A2+)) crossed with two nutrient levels (low (LN) and high (HN)) with four replicates. The facility includes 24 mesocosms mimicking shallow lakes, which at the time of our experiment had run without interruption for 11 years. The 1-month heat wave effect was simulated by increasing the temperature by 5 °C (1 July to 1 August) in A2 and A2+, while A0 was not additionally heated. Throughout the study, HN treatments were mostly dominated by Cyanobacteria, whereas LN treatments were richer in genera and mostly dominated by Chlorophyta. Linear mixed model analyses revealed that high nutrient conditions were the most important structuring factor, which, regardless of temperature treatments and heat waves, increased total phytoplankton, Chlorophyta, Bacillariophyta, and Cyanobacteria biomasses and decreased genus richness and the grazing pressure of zooplankton. The effect of temperature was, however, modest. The effect of warming on the phytoplankton community was not significant before the heat wave, yet during the heat wave it became significant, especially in LN-A2+, and negative interaction effects between nutrient and A2+ warming were recorded. These warming effects continued after the heat wave, as also evidenced by Co-inertia analyses. In contrast to the prevailing theory stating that more diverse ecosystems would be more stable, HN were less affected by the heat wave disturbance, most likely because the dominant phytoplankton group cyanobacteria is adapted to high nutrient conditions and also benefits from increased temperature. We did not find any significant change in phytoplankton size diversity, but size evenness decreased in HN as a result of an increase in the smallest and largest size classes simultaneously. We conclude that the phytoplankton community was most strongly affected by the nutrient level, but less sensitive to changes in both temperature treatments and the heat wave simulation in these systems, which have been adapted for a long time to different temperatures. Moreover, the temperature and heat wave effects were observed mostly in LN systems, indicating that the sensitivity of phytoplankton community structure to high temperatures is dependent on nutrient availability.
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15
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Bai G, Zhang Y, Yan P, Yan W, Kong L, Wang L, Wang C, Liu Z, Liu B, Ma J, Zuo J, Li J, Bao J, Xia S, Zhou Q, Xu D, He F, Wu Z. Spatial and seasonal variation of water parameters, sediment properties, and submerged macrophytes after ecological restoration in a long-term (6 year) study in Hangzhou west lake in China: Submerged macrophyte distribution influenced by environmental variables. WATER RESEARCH 2020; 186:116379. [PMID: 32911268 DOI: 10.1016/j.watres.2020.116379] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 08/24/2020] [Accepted: 08/25/2020] [Indexed: 06/11/2023]
Abstract
Submerged macrophyte restoration is the key stage in the reestablishment of an aquatic ecosystem. Previous studies have paid considerable attention to the effect of multiple environmental factors on submerged macrophytes. Meanwhile, few studies have been conducted regarding the spatial and seasonal characteristics of water and sediment properties and their long-term relationship with submerged macrophytes after the implementation of the submerged macrophytes restoration project. On a monthly basis, we monitored the spatial and seasonal variation in water parameters, sediment properties, and the submerged macrophyte characteristics of West Lake in Hangzhou from August 2013 to July 2019. From these measurements, we characterized the relationship between environmental factors and submerged macrophytes. Water nutrient concentrations continuously decreased with time, and the accumulation of sediment nutrients was accelerated as the submerged macrophyte communities developed on a long-term scale. The results indicated that the difference in water parameters was due to seasonal changes and land-use types in the watershed. The differences in the sediment properties were mainly attributed to seasonal changes and changes in the flow field. Redundancy analysis showed that the influence of water nutrients on the submerged macrophyte distribution was greater than that of sediment nutrients. The result also suggested that the developed root system, high stoichiometric homeostasis coefficients of P, and compensation ability of substantial leaf tissue may lead to a large distribution of Vallisneria natans in West Lake in Hangzhou. The correlation of water parameters and sediment properties with submerged macrophytes for a long time was very important as the restoration was achieved. To ensure the stability of the aquatic ecosystem after performing the submerged macrophyte restoration, a greater emphasis must be placed on reestablishing the entire ecosystem, including the restoration of aquatic animals and fish stocks. We expect these findings to serve as a reference for researchers and government agencies in the field of aquatic ecosystem restoration.
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Affiliation(s)
- Guoliang Bai
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
| | - Yi Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
| | - Pan Yan
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Wenhao Yan
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; School of Environmental Studies, China University of Geosciences, Wuhan 430074, China
| | - Lingwei Kong
- Environmental Research and Design Institute of Zhejiang Province, Hangzhou 310007, China
| | - Lai Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Chuan Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Zisen Liu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Biyun Liu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Jianmin Ma
- College of Life Sciences, Henan Normal University, Xinxiang 453007, China
| | - Jincheng Zuo
- College of Life Sciences, Ludong University, Yantai 264025, China
| | - Jin Li
- Life Science School, Hubei Normal University, Huangshi 435002, China
| | - Jing Bao
- Hangzhou Administration of West Lake Water Areas (The Environmental Monitoring Station of Hangzhou West Lake Scenic Area) Hangzhou 310002, China
| | - Shibin Xia
- School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China
| | - Qiaohong Zhou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Dong Xu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Feng He
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Zhenbin Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; School of Environmental Studies, China University of Geosciences, Wuhan 430074, China.
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