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Chi, X., Mueller-Navarra, D. C., Hylander, S., Sommer, U. & Javidpour, J. (2019). Food quality matters: interplay among food quality, food quantity and temperature affecting life history traits of Aurelia aurita (Cnidaria: Scyphozoa) polyps. Science of the Total Environment, 656, 1280-1288
Open this publication in new window or tab >>Food quality matters: interplay among food quality, food quantity and temperature affecting life history traits of Aurelia aurita (Cnidaria: Scyphozoa) polyps
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2019 (English)In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 656, p. 1280-1288Article in journal (Refereed) Epub ahead of print
Abstract [en]

Understanding the interaction between organisms' life history traits and environmental factors is an essential task in ecology. In spite of the increasing appreciation of jellyfish as an important component in marine ecosystem, there are still considerable gaps in understanding how the phase transition from the benthic polyp to the pelagic medusa stage is influenced by multiple environmental factors, including nutrition. To investigate survival, growth, and phase transition of Aurelia aurita polyps, we designed a factorial experiment manipulating food quantity (20μg C, 5μg C and 1.5μg C polyp−1 every other day), food quality (Artemia salina and two dietary manipulated Acartia tonsa), and temperature (13°C, 20°C, and 27°C). Temperature was the key factor determining phase transition of polyps and negatively affecting their survival rate and growth at 27°C, which reflected a summer heatwave scenario. Furthermore, at polyps' optimum tolerance temperature (20°C) in our study, budding reproduction benefits from high food concentrations. Interestingly, polyps fed with food containing high level highly unsaturated fatty acid (HUFA) were able to compensate for physiological stress caused by the extreme temperature, and could enhance budding reproduction at optimum temperature. Moreover, benthic-pelagic coupling (strobilation) was determined by temperature but affected significantly by food conditions. Mild temperature together with optimum food conditions contributes to inducing more polyps, which may potentially bring about great ephyrae recruitments during overwintering. In contrast, heatwave events can potentially regulate plankton community structure accompanied by changes of nutritional conditions of primary and secondary producers and thus, negatively affect the population dynamics of polyps. We suggest a novel polyp tolerance curve, which can help to understand jellyfish population dynamics in different seasons and ecosystems. This sets up a baseline for understanding how anticipated global warming and food conditions may affect the population size of benthic polyps and consequently pelagic medusae.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Life history, Multiple stressors, Asexual reproduction, Phase transition, Tolerance curve, Jellyfish
National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-79142 (URN)10.1016/j.scitotenv.2018.11.469 (DOI)
Projects
EcoChange
Funder
Ecosystem dynamics in the Baltic Sea in a changing climate perspective - ECOCHANGE
Available from: 2018-12-10 Created: 2018-12-10 Last updated: 2018-12-10
Bais, A. F., Lucas, R. M., Bornman, J. F., Williamson, C. E., Sulzberger, B., Austin, A. T., . . . Heikkila, A. M. (2018). Environmental effects of ozone depletion, UV radiation and interactions with climate change: UNEP Environmental Effects Assessment Panel, update 2017. Photochemical and Photobiological Sciences, 17(2), 127-179
Open this publication in new window or tab >>Environmental effects of ozone depletion, UV radiation and interactions with climate change: UNEP Environmental Effects Assessment Panel, update 2017
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2018 (English)In: Photochemical and Photobiological Sciences, ISSN 1474-905X, E-ISSN 1474-9092, Vol. 17, no 2, p. 127-179Article in journal (Refereed) Published
Abstract [en]

The Environmental Effects Assessment Panel (EEAP) is one of three Panels of experts that inform the Parties to the Montreal Protocol. The EEAP focuses on the effects of UV radiation on human health, terrestrial and aquatic ecosystems, air quality, and materials, as well as on the interactive effects of UV radiation and global climate change. When considering the effects of climate change, it has become clear that processes resulting in changes in stratospheric ozone are more complex than previously held. Because of the Montreal Protocol, there are now indications of the beginnings of a recovery of stratospheric ozone, although the time required to reach levels like those before the 1960s is still uncertain, particularly as the effects of stratospheric ozone on climate change and vice versa, are not yet fully understood. Some regions will likely receive enhanced levels of UV radiation, while other areas will likely experience a reduction in UV radiation as ozone- and climate-driven changes affect the amounts of UV radiation reaching the Earth's surface. Like the other Panels, the EEAP produces detailed Quadrennial Reports every four years; the most recent was published as a series of seven papers in 2015 (Photochem. Photobiol. Sci., 2015, 14, 1-184). In the years in between, the EEAP produces less detailed and shorter Update Reports of recent and relevant scientific findings. The most recent of these was for 2016 (Photochem. Photobiol. Sci., 2017, 16, 107-145). The present 2017 Update Report assesses some of the highlights and new insights about the interactive nature of the direct and indirect effects of UV radiation, atmospheric processes, and climate change. A full 2018 Quadrennial Assessment, will be made available in 2018/2019.

Place, publisher, year, edition, pages
Royal Society of Chemistry, 2018
National Category
Climate Research Environmental Sciences
Research subject
Natural Science, Environmental Science
Identifiers
urn:nbn:se:lnu:diva-71223 (URN)10.1039/c7pp90043k (DOI)000425174200001 ()29404558 (PubMedID)
Available from: 2018-03-02 Created: 2018-03-02 Last updated: 2018-03-02Bibliographically approved
Paerl, R. W., Sundh, J., Tan, D., Svenningsen, S. L., Hylander, S., Pinhassi, J., . . . Riemann, L. (2018). Prevalent reliance of bacterioplankton on exogenous vitamin B1 and precursor availability. Proceedings of the National Academy of Sciences of the United States of America, 115(44), E10447-E10456
Open this publication in new window or tab >>Prevalent reliance of bacterioplankton on exogenous vitamin B1 and precursor availability
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2018 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 115, no 44, p. E10447-E10456Article in journal (Refereed) Published
Abstract [en]

Vitamin B1 (B1 herein) is a vital enzyme cofactor required by virtually all cells, including bacterioplankton, which strongly influence aquatic biogeochemistry and productivity and modulate climate on Earth. Intriguingly, bacterioplankton can be de novo B1 synthesizers or B1 auxotrophs, which cannot synthesize B1 de novo and require exogenous B1 or B1 precursors to survive. Recent isolate-based work suggests select abundant bacterioplankton are B1 auxotrophs, but direct evidence of B1 auxotrophy among natural communities is scant. In addition, it is entirely unknown if bulk bacterioplankton growth is ever B1-limited. We show by surveying for B1-related genes in estuarine, marine, and freshwater metagenomes and metagenome-assembled genomes (MAGs) that most naturally occurring bacterioplankton are B1 auxotrophs. Pyrimidine B1-auxotrophic bacterioplankton numerically dominated metagenomes, but multiple other B1-auxotrophic types and distinct uptake and B1-salvaging strategies were also identified, including dual (pyrimidine and thiazole) and intact B1 auxotrophs that have received little prior consideration. Time-series metagenomes from the Baltic Sea revealed pronounced shifts in the prevalence of multiple B1-auxotrophic types and in the B1-uptake and B1-salvaging strategies over time. Complementarily, we documented B1/precursor limitation of bacterioplankton production in three of five nutrient-amendment experiments at the same time-series station, specifically when intact B1 concentrations were ≤3.7 pM, based on bioassays with a genetically engineered Vibrio anguillarum B1-auxotrophic strain. Collectively, the data presented highlight the prevalent reliance of bacterioplankton on exogenous B1/precursors and on the bioavailability of the micronutrients as an overlooked factor that could influence bacterioplankton growth and succession and thereby the cycling of nutrients and energy in aquatic systems.

Place, publisher, year, edition, pages
National Academy of Sciences, 2018
Keywords
vitamin B1, thiamin, bacterioplankton, metagenomics, growth limitation
National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-78320 (URN)10.1073/pnas.1806425115 (DOI)000448713200018 ()30322929 (PubMedID)
Available from: 2018-10-16 Created: 2018-10-16 Last updated: 2018-11-15Bibliographically approved
Fridolfsson, E., Lindehoff, E., Legrand, C. & Hylander, S. (2018). Thiamin (vitamin B1) content in phytoplankton and zooplankton in the presence of filamentous cyanobacteria. Limnology and Oceanography, 63(6), 2423-2435
Open this publication in new window or tab >>Thiamin (vitamin B1) content in phytoplankton and zooplankton in the presence of filamentous cyanobacteria
2018 (English)In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 63, no 6, p. 2423-2435Article in journal (Refereed) Published
Abstract [en]

Top predators in several aquatic food webs regularly display elevated reproductive failure, caused by thiamin(vitamin B1)deficiency. The reasons for these low-thiamin levels are not understood and information about the transfer of thiamin from the producers (bacteria and phytoplankton) to higher trophic levels is limited. One main concern is whether cyanobacterial blooms could negatively affect thiamin transfer in aquatic systems. Laboratory experiments with Baltic Sea plankton communities and single phytoplankton species were used to study the effect of filamentous cyanobacteria on the transfer of thiamin from phytoplankton to zooplankton. Experiments showed that the thiamin content in copepods was reduced when exposed to elevated levels of cyanobacteria, although filamentous cyanobacteria had higher levels of thiamin than any other analyzed phytoplankton species. Filamentous cyanobacteria also had a negative effect on copepod egg production despite high concentrations of non-cyanobacterial food. Phytoplankton species composition affected overall thiamin concentration with relatively more thiamin available for transfer when the relative abundance of Dinophyceae was higher. Finally, phytoplankton thiamin levels were lower when copepods were abundant, indicating that grazers affect thiamin levels in phytoplankton community, likely by selective feeding. Overall, high levels of thiamin in phytoplankton communities are not reflected in the copepod community. We conclude that presence of filamentous cyanobacteria during summer potentially reduces the transfer of thiamin to higher trophic levels by negatively affecting phytoplankton and copepod thiamin content as well as copepod reproduction, thereby lowering the absolute capacity of the food web to transfer thiamin through copepods to higher trophic levels.

Place, publisher, year, edition, pages
John Wiley & Sons, 2018
Keywords
Acartia sp., Baltic Sea, community composition, trophic transfer, micronutrient, copepod
National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-77174 (URN)10.1002/lno.10949 (DOI)000450233300009 ()
Projects
EcoChangeCentre for Ecology and Evolution in Microbial Model Systems - EEMiS
Funder
Swedish Research Council Formas, 215-2012-1319Ecosystem dynamics in the Baltic Sea in a changing climate perspective - ECOCHANGECarl Tryggers foundation The Royal Swedish Academy of Sciences
Available from: 2018-08-17 Created: 2018-08-17 Last updated: 2018-12-06Bibliographically approved
Heuschele, J., Ekvall, M. T., Bianco, G., Hylander, S. & Hansson, L.-A. (2017). Context-dependent individual behavioral consistency in Daphnia. Ecosphere, 8(2), Article ID e01679.
Open this publication in new window or tab >>Context-dependent individual behavioral consistency in Daphnia
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2017 (English)In: Ecosphere, ISSN 2150-8925, E-ISSN 2150-8925, Vol. 8, no 2, article id e01679Article in journal (Refereed) Published
Abstract [en]

The understanding of consistent individual differences in behavior, often termed “personality,” for adapting and coping with threats and novel environmental conditions has advanced considerably during the last decade. However, advancements are almost exclusively associated with higher-order animals, whereas studies focusing on smaller aquatic organisms are still rare. Here, we show individual differences in the swimming behavior of Daphnia magna, a clonal freshwater invertebrate, before, during, and after being exposed to a lethal threat, ultraviolet radiation (UVR). We show consistency in swimming velocity among both mothers and daughters of D. magna in a neutral environment, whereas this pattern breaks down when exposed to UVR. Our study also, for the first time, illustrates how the ontogenetic development in swimming and refuge-seeking behavior of young individuals eventually approaches that of adults. Overall, we show that aquatic invertebrates are far from being identical robots, but instead they show considerable individual differences in behavior that can be attributed to both ontogenetic development and individual consistency. Our study also demonstrates, for the first time, that behavioral consistency and repeatability, that is, something resembling “personality,” is context and state dependent in this zooplankter taxa.

Keywords
animal personality, behavioral type, Daphnia, UV radiation, zooplankton
National Category
Ecology
Research subject
Natural Science, Ecology
Identifiers
urn:nbn:se:lnu:diva-61179 (URN)10.1002/ecs2.1679 (DOI)000397091300015 ()
Projects
EcoChange
Available from: 2017-03-08 Created: 2017-03-08 Last updated: 2018-10-24Bibliographically approved
Broman, E., Sachpazidou, V., Dopson, M. & Hylander, S. (2017). Diatoms dominate the eukaryotic metatranscriptome during spring in coastal 'dead zone' sediments. Proceedings of the Royal Society of London. Biological Sciences, 284(1864), Article ID 20171617.
Open this publication in new window or tab >>Diatoms dominate the eukaryotic metatranscriptome during spring in coastal 'dead zone' sediments
2017 (English)In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 284, no 1864, article id 20171617Article in journal (Refereed) Published
Abstract [en]

An important characteristic of marine sediments is the oxygen concentration that affects many central metabolic processes. There has been a widespread increase in hypoxia in coastal systems (referred to as 'dead zones') mainly caused by eutrophication. Hence, it is central to understand the metabolism and ecology of eukaryotic life in sediments during changing oxygen conditions. Therefore, we sampled coastal 'dead zone' Baltic Sea sediment during autumn and spring, and analysed the eukaryotic metatranscriptome from field samples and after incubation in the dark under oxic or anoxic conditions. Bacillariophyta (diatoms) dominated the eukaryotic metatranscriptome in spring and were also abundant during autumn. A large fraction of the diatom RNA reads was associated with the photosystems suggesting a constitutive expression in darkness. Microscope observation showed intact diatom cells and these would, if hatched, represent a significant part of the pelagic phytoplankton biomass. Oxygenation did not significantly change the relative proportion of diatoms nor resulted in any major shifts in metabolic 'signatures'. By contrast, diatoms rapidly responded when exposed to light suggesting that light is limiting diatom development in hypoxic sediments. Hence, it is suggested that diatoms in hypoxic sediments are on 'standby' to exploit the environment if they reach suitable habitats.

Keywords
diatoms, sediment, oxygen, anoxia, metatranscriptomics
National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-68552 (URN)10.1098/rspb.2017.1617 (DOI)000412553400005 ()
Projects
EcoChange
Funder
Ecosystem dynamics in the Baltic Sea in a changing climate perspective - ECOCHANGE
Available from: 2017-11-01 Created: 2017-11-01 Last updated: 2018-10-24Bibliographically approved
Andrady, A., Aucamp, P. J., Austin, A. T., Bais, A. F., Ballare, C. L., Barnes, P. W., . . . Zepp, R. G. (2017). Environmental effects of ozone depletion and its interactions with climate change: Progress report, 2016. Photochemical and Photobiological Sciences, 16(2), 107-145
Open this publication in new window or tab >>Environmental effects of ozone depletion and its interactions with climate change: Progress report, 2016
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2017 (English)In: Photochemical and Photobiological Sciences, ISSN 1474-905X, E-ISSN 1474-9092, Vol. 16, no 2, p. 107-145Article in journal (Refereed) Published
Abstract [en]

The Parties to the Montreal Protocol are informed by three Panels of experts. One of these is the Environmental Effects Assessment Panel (EEAP), which deals with two focal issues. The first focus is the effects of UV radiation on human health, animals, plants, biogeochemistry, air quality, and materials. The second focus is on interactions between UV radiation and global climate change and how these may affect humans and the environment. When considering the effects of climate change, it has become clear that processes resulting in changes in stratospheric ozone are more complex than previously believed. As a result of this, human health and environmental issues will be longer-lasting and more regionally variable. Like the other Panels, the EEAP produces a detailed report every four years; the most recent was published as a series of seven papers in 2015 (Photochem. Photobiol. Sci., 2015, 14, 1-184). In the years in between, the EEAP produces less detailed and shorter Progress Reports of the relevant scientific findings. The most recent of these was for 2015 (Photochem. Photobiol. Sci., 2016, 15, 141-147). The present Progress Report for 2016 assesses some of the highlights and new insights with regard to the interactive nature of the direct and indirect effects of UV radiation, atmospheric processes, and climate change. The more detailed Quadrennial Assessment will bemade available in 2018.

Place, publisher, year, edition, pages
Royal Society of Chemistry, 2017
National Category
Environmental Sciences
Research subject
Natural Science, Environmental Science
Identifiers
urn:nbn:se:lnu:diva-67093 (URN)10.1039/c7pp90001e (DOI)000395697000001 ()28124708 (PubMedID)
Projects
EcoChange
Available from: 2017-07-26 Created: 2017-07-26 Last updated: 2018-04-24Bibliographically approved
Neuheimer, A. B., Hartvig, M., Hylander, S., Kiorboe, T., Olsson, K. H., Saimont, J. & Andersen, K. H. (2016). Adult and offspring size in the ocean: a database of size metrics and conversion factors. John Wiley & Sons
Open this publication in new window or tab >>Adult and offspring size in the ocean: a database of size metrics and conversion factors
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2016 (English)Data set
Abstract [en]

The purpose of this dataset was to compile adult and offspring size estimates for marine organisms. Adult and offspring size estimates of 408 species were compiled from the literature covering >17 orders of magnitude in body mass and including Cephalopoda (ink fish), Cnidaria (“jelly” fish), Crustaceans, Ctenophora (comb jellies), Elasmobranchii (cartilaginous fish), Mammalia (mammals), Sagittoidea (arrow worms) and Teleost (i.e., Actinopterygii, bony fish). Individual size estimates were converted to standardized size estimates (carbon weight, g) to allow for among-group comparisons. This required a number of size estimates to be converted and a compilation of conversion factors obtained from the literature are also presented.

Place, publisher, year
John Wiley & Sons, 2016
National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-59429 (URN)10.1890/15-1261.1 (DOI)
Projects
EcoChange
Note

Published in Ecology, 2016, 97(4):1083

The complete data sets corresponding to abstracts published in the Data Papers section in the journal are published electronically as Supporting Information in the online version of this article at http://onlinelibrary.wiley.com/doi/10.1890/15-1261.1/suppinfo

Available from: 2016-12-20 Created: 2016-12-20 Last updated: 2018-10-24Bibliographically approved
Andersen, K. H., Berge, T., Goncalves, R. J., Hartvig, M., Heuschele, J., Hylander, S., . . . Kiorboe, T. (2016). Characteristic Sizes of Life in the Oceans, from Bacteria to Whales. Annual Review of Marine Science, 8, 217-241
Open this publication in new window or tab >>Characteristic Sizes of Life in the Oceans, from Bacteria to Whales
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2016 (English)In: Annual Review of Marine Science, ISSN 1941-1405, E-ISSN 1941-0611, Vol. 8, p. 217-241Article in journal (Refereed) Published
Abstract [en]

The size of an individual organism is a key trait to characterize its physiology and feeding ecology. Size-based scaling laws may have a limited size range of validity or undergo a transition from one scaling exponent to another at some characteristic size. We collate and review data on size-based scaling laws for resource acquisition, mobility, sensory range, and progeny size for all pelagic marine life, from bacteria to whales. Further, we review and develop simple theoretical arguments for observed scaling laws and the characteristic sizes of a change or breakdown of power laws. We divide life in the ocean into seven major realms based on trophic strategy, physiology, and life history strategy. Such a categorization represents a move away from a taxonomically oriented description toward a trait-based description of life in the oceans. Finally, we discuss life forms that transgress the simple size-based rules and identify unanswered questions.

Keywords
body size, metabolism, allometric scaling, plankton, mixotrophy, fish, whales
National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-49730 (URN)10.1146/annurev-marine-122414-034144 (DOI)000368369200010 ()26163011 (PubMedID)2-s2.0-84953223124 (Scopus ID)978-0-8243-4508-2 (ISBN)
Projects
EcoChange
Available from: 2016-02-12 Created: 2016-02-12 Last updated: 2018-04-24Bibliographically approved
Brüsin, M., Svensson, P. A. & Hylander, S. (2016). Individual changes in zooplankton pigmentation in relation to ultraviolet radiation and predator cues. Limnology and Oceanography, 61(4), 1337-1344
Open this publication in new window or tab >>Individual changes in zooplankton pigmentation in relation to ultraviolet radiation and predator cues
2016 (English)In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 61, no 4, p. 1337-1344Article in journal (Refereed) Published
Abstract [en]

Copepods are common crustaceans in aquatic systems and one of the most important producers of carotenoidastaxanthin pigments, which can enhance the animals’ resistance against potentially damaging ultraviolet radiation (UVR), but at the same time, increases the risk of fish predation. Previous studies have demonstrated that copepods have different pigmentation levels matching the current threat level in terms of UVR and fish occurrence. However, these other studies have quantified population-levels changes in pigmentation, making it difficult to disentangle the role of individual phenotypic colour changes from that of selection.We quantified carotenoid-based pigmentation with colorimetric methods, which enabled us to track changes within individual copepods. Two species of copepods, Diaptomus castor and Eudiaptomus gracilis, were exposed to high and low UVR and fish cues in a factorial design. L*a*b* colour values (CIE; CommissionInternational de l’Eclairage) were extracted from digital photographs of each copepod and used as proxies for carotenoid concentration. Our results showed that individual copepods significantly changed their pigmentation in response to both UVR and fish cues within a period of 2 weeks. However, the responses differed between sexes and between adults and juveniles. UVR effects were present in all life-stages whereas fish effects were only detected in juveniles, with largest responses in D. castor. This confirms that carotenoid pigmentation is a phenotypically plastic trait, and highlights that strategies for trading off risks of UVR and predation differ between males and females as well as between life-stages.

National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-51844 (URN)10.1002/lno.10303 (DOI)000383622900014 ()2-s2.0-84969915314 (Scopus ID)
Projects
EcoChange
Available from: 2016-04-01 Created: 2016-04-01 Last updated: 2018-04-24Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-3740-5998

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