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Accounting for environmental variation in co-occurrence modelling reveals the importance of positive interactions in root-associated fungal communities.

https://arctichealth.org/en/permalink/ahliterature305463
Source
Mol Ecol. 2020 07; 29(14):2736-2746
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
07-2020
Author
Nerea Abrego
Tomas Roslin
Tea Huotari
Ayco J M Tack
Björn D Lindahl
Gleb Tikhonov
Panu Somervuo
Niels Martin Schmidt
Otso Ovaskainen
Author Affiliation
Department of Agricultural Sciences, University of Helsinki, Helsinki, Finland.
Source
Mol Ecol. 2020 07; 29(14):2736-2746
Date
07-2020
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Abstract
Understanding the role of interspecific interactions in shaping ecological communities is one of the central goals in community ecology. In fungal communities, measuring interspecific interactions directly is challenging because these communities are composed of large numbers of species, many of which are unculturable. An indirect way of assessing the role of interspecific interactions in determining community structure is to identify the species co-occurrences that are not constrained by environmental conditions. In this study, we investigated co-occurrences among root-associated fungi, asking whether fungi co-occur more or less strongly than expected based on the environmental conditions and the host plant species examined. We generated molecular data on root-associated fungi of five plant species evenly sampled along an elevational gradient at a high arctic site. We analysed the data using a joint species distribution modelling approach that allowed us to identify those co-occurrences that could be explained by the environmental conditions and the host plant species, as well as those co-occurrences that remained unexplained and thus more probably reflect interactive associations. Our results indicate that not only negative but also positive interactions play an important role in shaping microbial communities in arctic plant roots. In particular, we found that mycorrhizal fungi are especially prone to positively co-occur with other fungal species. Our results bring new understanding to the structure of arctic interaction networks by suggesting that interactions among root-associated fungi are predominantly positive.
PubMed ID
32562300 View in PubMed
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An ecosystem-wide reproductive failure with more snow in the Arctic.

https://arctichealth.org/en/permalink/ahliterature308639
Source
PLoS Biol. 2019 10; 17(10):e3000392
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
10-2019
Author
Niels Martin Schmidt
Jeroen Reneerkens
Jens Hesselbjerg Christensen
Martin Olesen
Tomas Roslin
Author Affiliation
Department of Bioscience, Aarhus University, Roskilde, Denmark.
Source
PLoS Biol. 2019 10; 17(10):e3000392
Date
10-2019
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Animals
Arctic Regions
Birds - physiology
Climate change
Ecosystem
Genetic Fitness
Mammals - physiology
Plant Dormancy
Plants
Rain
Seasons
Abstract
2018: Arctic researchers have just witnessed another extreme summer-but in a new sense of the word. Although public interest has long been focused on general warming trends and trends towards a lower sea ice cover in the Arctic Ocean, this summer saw the realization of another predicted trend: that of increasing precipitation during the winter months and of increased year-to-year variability. In a well-studied ecosystem in Northeast Greenland, this resulted in the most complete reproductive failure encountered in the terrestrial ecosystem during more than two decades of monitoring: only a few animals and plants were able to reproduce because of abundant and late melting snow. These observations, we suggest, should open our eyes to potentially drastic consequences of predicted changes in both the mean and the variability of arctic climate.
PubMed ID
31613872 View in PubMed
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Arctic terrestrial biodiversity status and trends: A synopsis of science supporting the CBMP State of Arctic Terrestrial Biodiversity Report.

https://arctichealth.org/en/permalink/ahliterature307249
Source
Ambio. 2020 Mar; 49(3):833-847
Publication Type
Editorial
Review
Date
Mar-2020
Author
Jason J Taylor
James P Lawler
Mora Aronsson
Tom Barry
Anne D Bjorkman
Tom Christensen
Stephen J Coulson
Christine Cuyler
Dorothee Ehrich
Knud Falk
Alastair Franke
Eva Fuglei
Mark A Gillespie
Starri Heiðmarsson
Toke Høye
Liza K Jenkins
Virve Ravolainen
Paul A Smith
Pawel Wasowicz
Niels Martin Schmidt
Author Affiliation
U.S. National Park Service, PO Box 517, Skagway, AK, 99840, USA. Jason_J_Taylor@nps.gov.
Source
Ambio. 2020 Mar; 49(3):833-847
Date
Mar-2020
Language
English
Publication Type
Editorial
Review
Keywords
Animals
Arctic Regions
Biodiversity
Birds
Ecosystem
Invertebrates
Abstract
This review provides a synopsis of the main findings of individual papers in the special issue Terrestrial Biodiversity in a Rapidly Changing Arctic. The special issue was developed to inform the State of the Arctic Terrestrial Biodiversity Report developed by the Circumpolar Biodiversity Monitoring Program (CBMP) of the Conservation of Arctic Flora and Fauna (CAFF), Arctic Council working group. Salient points about the status and trends of Arctic biodiversity and biodiversity monitoring are organized by taxonomic groups: (1) vegetation, (2) invertebrates, (3) mammals, and (4) birds. This is followed by a discussion about commonalities across the collection of papers, for example, that heterogeneity was a predominant pattern of change particularly when assessing global trends for Arctic terrestrial biodiversity. Finally, the need for a comprehensive, integrated, ecosystem-based monitoring program, coupled with targeted research projects deciphering causal patterns, is discussed.
PubMed ID
31955399 View in PubMed
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Are gastrointestinal parasites associated with the cyclic population dynamics of their arctic lemming hosts?

https://arctichealth.org/en/permalink/ahliterature301888
Source
Int J Parasitol Parasites Wildl. 2019 Dec; 10:6-12
Publication Type
Journal Article
Date
Dec-2019
Author
Olivier Gilg
Loïc Bollache
Eve Afonso
Glenn Yannic
Niels Martin Schmidt
Lars Holst Hansen
Jannik Hansen
Benoît Sittler
Johannes Lang
Nicolas Meyer
Brigitte Sabard
Vladimir Gilg
Anita Lang
Mathilde Lebbar
Voitto Haukisalmi
Heikki Henttonen
Jérôme Moreau
Author Affiliation
Laboratoire Chrono-environnement, UMR 6249 CNRS-UFC, Université de Franche-Comté, 25000, Besançon, France.
Source
Int J Parasitol Parasites Wildl. 2019 Dec; 10:6-12
Date
Dec-2019
Language
English
Publication Type
Journal Article
Abstract
Many rodents, including most populations of arctic lemmings (genus Dicrostonyx and Lemmus), have cyclic population dynamics. Among the numerous hypotheses which have been proposed and tested to explain this typical characteristic of some terrestrial vertebrate communities, trophic interactions have often been presented as the most likely drivers of these periodic fluctuations. The possible role of parasites has, however, only seldom been assessed. In this study, we genetically measured the prevalence of two endoparasite taxa, eimerians and cestodes, in 372 faecal samples from collared lemmings, over a five year period and across three distant sites in Northeast Greenland. Prevalence of cestodes was low (2.7% over all sites and years) and this taxon was only found at one site (although in 4 out of 5 years) in adult hosts. By contrast, we found high prevalence for eimerians (77.7% over all sites and years), which occurred at all sites, in every year, for both age classes (at the Hochstetter Forland site where both adult and juvenile faeces were collected) and regardless of reproductive and social status inferred from the characteristics of the lemming nests where the samples had been collected. Prevalence of eimerians significantly varied among years (not among sites) and was higher for juvenile than for adult lemmings at the Hochstetter Forland site. However, higher prevalence of eimerians (Pt ) was only associated with lower lemming density (Nt ) at one of the three sites and we found no delayed density dependence between Nt and Pt+1 to support the parasite hypothesis. Our results show that there is no clear relation between lemming density and eimerian faecal prevalence in Northeast Greenland and hence no evidence that eimerians could be driving the cyclic population dynamics of collared lemmings in this region.
PubMed ID
31321206 View in PubMed
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Catchment vegetation and temperature mediating trophic interactions and production in plankton communities.

https://arctichealth.org/en/permalink/ahliterature282411
Source
PLoS One. 2017;12(4):e0174904
Publication Type
Article
Date
2017
Author
Anders G Finstad
Erlend B Nilsen
Ditte K Hendrichsen
Niels Martin Schmidt
Source
PLoS One. 2017;12(4):e0174904
Date
2017
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Bayes Theorem
Climate change
Ecosystem
Fishes - physiology
Food chain
Lakes
Models, Biological
Phytoplankton - growth & development - physiology
Plankton - growth & development - physiology
Temperature
Zooplankton - growth & development - physiology
Abstract
Climatic factors influence the interactions among trophic levels in an ecosystem in multiple ways. However, whereas most studies focus on single factors in isolation, mainly due to interrelation and correlation among drivers complicating interpretation and analyses, there are still only few studies on how multiple ecosystems respond to climate related factors at the same time. Here, we use a hierarchical Bayesian model with a bioenergetic predator-prey framework to study how different climatic factors affect trophic interactions and production in small Arctic lakes. Natural variation in temperature and catchment land-cover was used as a natural experiment to exemplify how interactions between and production of primary producers (phytoplankton) and grazers (zooplankton) are driven by direct (temperature) and indirect (catchment vegetation) factors, as well as the presence or absence of apex predators (fish). The results show that increased vegetation cover increased phytoplankton growth rate by mediating lake nutrient concentration. At the same time, increased temperature also increased grazing rates by zooplankton. Presence of fish increased zooplankton mortality rates, thus reducing grazing. The Arctic is currently experiencing an increase in both temperature and shrub vegetation cover due to climate change, a trend, which is likely to continue. Our results point towards a possible future general weakening of zooplankton grazing on phytoplankton and greening of arctic lakes with increasing temperatures. At the same time, the impact of the presence of an apex predator indicate considerable local variation in the response. This makes direction and strength of global change impacts difficult to forecast.
Notes
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PubMed ID
28414736 View in PubMed
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Circumpolar status of Arctic ptarmigan: Population dynamics and trends.

https://arctichealth.org/en/permalink/ahliterature299777
Source
Ambio. 2019 May 09; :
Publication Type
Journal Article
Date
May-09-2019
Author
Eva Fuglei
John-André Henden
Chris T Callahan
Olivier Gilg
Jannik Hansen
Rolf A Ims
Arkady P Isaev
Johannes Lang
Carol L McIntyre
Richard A Merizon
Oleg Y Mineev
Yuri N Mineev
Dave Mossop
Olafur K Nielsen
Erlend B Nilsen
Åshild Ønvik Pedersen
Niels Martin Schmidt
Benoît Sittler
Maria Hørnell Willebrand
Kathy Martin
Author Affiliation
Norwegian Polar Institute, Fram Centre, Postbox 6606, Langnes, 9296, Tromsø, Norway. eva.fuglei@npolar.no.
Source
Ambio. 2019 May 09; :
Date
May-09-2019
Language
English
Publication Type
Journal Article
Abstract
Rock ptarmigan (Lagopus muta) and willow ptarmigan (L. lagopus) are Arctic birds with a circumpolar distribution but there is limited knowledge about their status and trends across their circumpolar distribution. Here, we compiled information from 90 ptarmigan study sites from 7 Arctic countries, where almost half of the sites are still monitored. Rock ptarmigan showed an overall negative trend on Iceland and Greenland, while Svalbard and Newfoundland had positive trends, and no significant trends in Alaska. For willow ptarmigan, there was a negative trend in mid-Sweden and eastern Russia, while northern Fennoscandia, North America and Newfoundland had no significant trends. Both species displayed some periods with population cycles (short 3-6 years and long 9-12 years), but cyclicity changed through time for both species. We propose that simple, cost-efficient systematic surveys that capture the main feature of ptarmigan population dynamics can form the basis for citizen science efforts in order to fill knowledge gaps for the many regions that lack systematic ptarmigan monitoring programs.
PubMed ID
31073984 View in PubMed
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Circumpolar status of Arctic ptarmigan: Population dynamics and trends.

https://arctichealth.org/en/permalink/ahliterature309515
Source
Ambio. 2020 Mar; 49(3):749-761
Publication Type
Journal Article
Date
Mar-2020
Author
Eva Fuglei
John-André Henden
Chris T Callahan
Olivier Gilg
Jannik Hansen
Rolf A Ims
Arkady P Isaev
Johannes Lang
Carol L McIntyre
Richard A Merizon
Oleg Y Mineev
Yuri N Mineev
Dave Mossop
Olafur K Nielsen
Erlend B Nilsen
Åshild Ønvik Pedersen
Niels Martin Schmidt
Benoît Sittler
Maria Hørnell Willebrand
Kathy Martin
Author Affiliation
Norwegian Polar Institute, Fram Centre, Postbox 6606, Langnes, 9296, Tromsø, Norway. eva.fuglei@npolar.no.
Source
Ambio. 2020 Mar; 49(3):749-761
Date
Mar-2020
Language
English
Publication Type
Journal Article
Keywords
Alaska
Animals
Arctic Regions
Galliformes
Greenland
North America
Population Dynamics
Russia
Svalbard
Sweden
Abstract
Rock ptarmigan (Lagopus muta) and willow ptarmigan (L. lagopus) are Arctic birds with a circumpolar distribution but there is limited knowledge about their status and trends across their circumpolar distribution. Here, we compiled information from 90 ptarmigan study sites from 7 Arctic countries, where almost half of the sites are still monitored. Rock ptarmigan showed an overall negative trend on Iceland and Greenland, while Svalbard and Newfoundland had positive trends, and no significant trends in Alaska. For willow ptarmigan, there was a negative trend in mid-Sweden and eastern Russia, while northern Fennoscandia, North America and Newfoundland had no significant trends. Both species displayed some periods with population cycles (short 3-6 years and long 9-12 years), but cyclicity changed through time for both species. We propose that simple, cost-efficient systematic surveys that capture the main feature of ptarmigan population dynamics can form the basis for citizen science efforts in order to fill knowledge gaps for the many regions that lack systematic ptarmigan monitoring programs.
PubMed ID
31073984 View in PubMed
Less detail

Comment on "Global pattern of nest predation is disrupted by climate change in shorebirds".

https://arctichealth.org/en/permalink/ahliterature301095
Source
Science. 2019 06 14; 364(6445):
Publication Type
Journal Article
Comment
Date
06-14-2019
Author
Martin Bulla
Jeroen Reneerkens
Emily L Weiser
Aleksandr Sokolov
Audrey R Taylor
Benoît Sittler
Brian J McCaffery
Dan R Ruthrauff
Daniel H Catlin
David C Payer
David H Ward
Diana V Solovyeva
Eduardo S A Santos
Eldar Rakhimberdiev
Erica Nol
Eunbi Kwon
Glen S Brown
Glenda D Hevia
H River Gates
James A Johnson
Jan A van Gils
Jannik Hansen
Jean-François Lamarre
Jennie Rausch
Jesse R Conklin
Joe Liebezeit
Joël Bêty
Johannes Lang
José A Alves
Juan Fernández-Elipe
Klaus-Michael Exo
Loïc Bollache
Marcelo Bertellotti
Marie-Andrée Giroux
Martijn van de Pol
Matthew Johnson
Megan L Boldenow
Mihai Valcu
Mikhail Soloviev
Natalya Sokolova
Nathan R Senner
Nicolas Lecomte
Nicolas Meyer
Niels Martin Schmidt
Olivier Gilg
Paul A Smith
Paula Machín
Rebecca L McGuire
Ricardo A S Cerboncini
Richard Ottvall
Rob S A van Bemmelen
Rose J Swift
Sarah T Saalfeld
Sarah E Jamieson
Stephen Brown
Theunis Piersma
Tomas Albrecht
Verónica D'Amico
Richard B Lanctot
Bart Kempenaers
Author Affiliation
Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, 82319 Seewiesen, Germany. bulla.mar@gmail.com b.kempenaers@orn.mpg.de.
Source
Science. 2019 06 14; 364(6445):
Date
06-14-2019
Language
English
Publication Type
Journal Article
Comment
Keywords
Animals
Arctic Regions
Climate change
Nesting Behavior
Predatory Behavior
Abstract
Kubelka et al (Reports, 9 November 2018, p. 680) claim that climate change has disrupted patterns of nest predation in shorebirds. They report that predation rates have increased since the 1950s, especially in the Arctic. We describe methodological problems with their analyses and argue that there is no solid statistical support for their claims.
Notes
CommentOn: Science. 2018 Nov 9;362(6415):680-683 PMID 30409881
CommentIn: Science. 2019 Jun 14;364(6445): PMID 31196987
PubMed ID
31196986 View in PubMed
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A Comparative Study on the Faecal Bacterial Community and Potential Zoonotic Bacteria of Muskoxen (Ovibos moschatus) in Northeast Greenland, Northwest Greenland and Norway.

https://arctichealth.org/en/permalink/ahliterature293401
Source
Microorganisms. 2018 Jul 25; 6(3):
Publication Type
Journal Article
Date
Jul-25-2018
Author
Emilie U Andersen-Ranberg
Christopher J Barnes
Linett Rasmussen
Alejandro Salgado-Flores
Carsten Grøndahl
Jesper B Mosbacher
Anders J Hansen
Monica Alterskjær Sundset
Niels Martin Schmidt
Christian Sonne
Author Affiliation
Department of Bioscience, Faculty of Science and Technology, Arctic Research Centre, Aarhus University, 4000 Roskilde, Denmark. emilie.ranberg@sund.ku.dk.
Source
Microorganisms. 2018 Jul 25; 6(3):
Date
Jul-25-2018
Language
English
Publication Type
Journal Article
Abstract
Muskoxen (Ovibos moschatus) are ruminants adapted to a high-fibre diet. There is increasing interest in the role that gut microbes play in the digestion and utilization of these specialized diets but only limited data available on the gut microbiome of high-Arctic animals. In this study, we metabarcoded the 16S rRNA region of faecal samples from muskoxen of Northeast Greenland, Northwest Greenland and Norway, and quantified the effects of physiological and temporal factors on bacterial composition. We found significant effects of body mass, year of sampling and location on the gut bacterial communities of North East Greenland muskoxen. These effects were however dwarfed by the effects of location, emphasizing the importance of the local ecology on the gut bacterial community. Habitat alterations and rising temperatures may therefore have a considerable impact on muskoxen health and reproductive success. Moreover, muskoxen are hunted and consumed in Greenland, Canada and Alaska; therefore, this study also screened for potential zoonoses of food safety interest. A total of 13 potentially zoonotic genera were identified, including the genera Erysipelothrix and Yersinia implicated in recent mass die-offs of the muskoxen themselves.
PubMed ID
30044373 View in PubMed
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Effects of food abundance and early clutch predation on reproductive timing in a high Arctic shorebird exposed to advancements in arthropod abundance.

https://arctichealth.org/en/permalink/ahliterature284074
Source
Ecol Evol. 2016 Oct;6(20):7375-7386
Publication Type
Article
Date
Oct-2016
Author
Jeroen Reneerkens
Niels Martin Schmidt
Olivier Gilg
Jannik Hansen
Lars Holst Hansen
Jérôme Moreau
Theunis Piersma
Source
Ecol Evol. 2016 Oct;6(20):7375-7386
Date
Oct-2016
Language
English
Publication Type
Article
Abstract
Climate change may influence the phenology of organisms unequally across trophic levels and thus lead to phenological mismatches between predators and prey. In cases where prey availability peaks before reproducing predators reach maximal prey demand, any negative fitness consequences would selectively favor resynchronization by earlier starts of the reproductive activities of the predators. At a study site in northeast Greenland, over a period of 17 years, the median emergence of the invertebrate prey of Sanderling Calidris alba advanced with 1.27 days per year. Yet, over the same period Sanderling did not advance hatching date. Thus, Sanderlings increasingly hatched after their prey was maximally abundant. Surprisingly, the phenological mismatches did not affect chick growth, but the interaction of the annual width and height of the peak in food abundance did. Chicks grew especially better in years when the food peak was broad. Sanderling clutches were most likely to be depredated early in the season, which should delay reproduction. We propose that high early clutch predation may favor a later reproductive timing. Additionally, our data suggest that in most years food was still abundant after the median date of emergence, which may explain why Sanderlings did not advance breeding along with the advances in arthropod phenology.
PubMed ID
28725405 View in PubMed
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28 records – page 1 of 3.