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Additive partitioning of testate amoeba species diversity across habitat hierarchy within the pristine southern taiga landscape (Pechora-Ilych Biosphere Reserve, Russia).

https://arctichealth.org/en/permalink/ahliterature262104
Source
Eur J Protistol. 2015 Feb;51(1):42-54
Publication Type
Article
Date
Feb-2015
Author
Andrey N Tsyganov
Alexander A Komarov
Edward A D Mitchell
Satoshi Shimano
Olga V Smirnova
Alexey A Aleynikov
Yuri A Mazei
Source
Eur J Protistol. 2015 Feb;51(1):42-54
Date
Feb-2015
Language
English
Publication Type
Article
Keywords
Amoeba - classification - physiology
Biodiversity
Russia
Soil - parasitology
Taiga
Abstract
In order to better understand the distribution patterns of terrestrial eukaryotic microbes and the factors governing them, we studied the diversity partitioning of soil testate amoebae across levels of spatially nested habitat hierarchy in the largest European old-growth dark coniferous forest (Pechora-Ilych Biosphere Reserve; Komi Republic, Russia). The variation in testate amoeba species richness and assemblage structure was analysed in 87 samples from six biotopes in six vegetation types using an additive partitioning procedure and principal component analyses. The 80 taxa recorded represent the highest value of species richness for soil testate amoebae reported for taiga soils so far. Our results indicate that testate amoeba assemblages were highly aggregated at all levels and were mostly controlled by environmental factors rather than dispersal processes. The variation in species diversity of testate amoebae increased from the lowest to the highest hierarchical level. We conclude that, similarly to macroscopic organisms, testate amoeba species richness and community structure are primarily controlled by environmental conditions within the landscape and suggest that metacommunity dynamics of free-living microorganisms are driven by species sorting and/or mass effect processes.
PubMed ID
25553551 View in PubMed
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Anthropogenic deposition of heavy metals and phosphorus may reduce biological N2 fixation in boreal forest mosses.

https://arctichealth.org/en/permalink/ahliterature292461
Source
Sci Total Environ. 2018 Jul 15; 630:203-210
Publication Type
Journal Article
Date
Jul-15-2018
Author
Dalton L Scott
Robert L Bradley
Jean-Philippe Bellenger
Daniel Houle
Michael J Gundale
Kathrin Rousk
Thomas H DeLuca
Author Affiliation
Université de Sherbrooke, Département de Biologie, Sherbrooke, Canada.
Source
Sci Total Environ. 2018 Jul 15; 630:203-210
Date
Jul-15-2018
Language
English
Publication Type
Journal Article
Keywords
Bryophyta
Bryopsida - drug effects - physiology
Environmental monitoring
Metals, Heavy - analysis - toxicity
Nitrogen - analysis
Nitrogen Fixation - drug effects
Norway
Phosphorus - analysis - toxicity
Taiga
Abstract
A study was undertaken to test the effects of molybdenum (Mo) and phosphorus (P) amendments on biological nitrogen (N) fixation (BNF) by boreal forest moss-associated cyanobacteria. Feather moss (Pleurozium schreberi) samples were collected on five sites, on two dates and at different roadside distances (0-100m) corresponding to an assumed gradient of reactive N deposition. Potential BNF of Mo and P amended moss samples was measured using the acetylene reduction assay. Total N, P and heavy metal concentrations of mosses collected at 0 and 100m from roadsides were also measured. Likewise, the needles from Norway spruce trees (Picea abies) at different roadside distances were collected in late summer and analyzed for total N, P and heavy metals. There was a significant increase in BNF with roadside distance on 7-of-10 individual Site×Date combinations. We found no clear evidence of an N gradient across roadside distances. Elemental analyses of feather moss and Norway spruce needle tissues suggested decreasing deposition of heavy metals (Mo-Co-Cr-Ni-V-Pb-Ag-Cu) as well as P with increasing distance from the roadside. The effects of Mo and P amendments on BNF were infrequent and inconsistent across roadside distances and across sites. One particular site, however, displayed greater concentrations of heavy metals near the roadside, as well as a steeper P fertility gradient with roadside distance, than the other sites. Here, BNF increased with roadside distance only when moss samples were amended with P. Also at this site, BNF across all roadside distances was higher when mosses were amended with both Mo and P, suggesting a co-limitation of these two nutrients in controlling BNF. In summary, our study showed a potential for car emissions to increase heavy metals and P along roadsides and underscored the putative roles of these anthropogenic pollutants on BNF in northern latitudes.
PubMed ID
29477819 View in PubMed
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Anthropogenic nitrogen deposition enhances carbon sequestration in boreal soils.

https://arctichealth.org/en/permalink/ahliterature272603
Source
Glob Chang Biol. 2015 Aug;21(8):3169-80
Publication Type
Article
Date
Aug-2015
Author
Nadia I Maaroufi
Annika Nordin
Niles J Hasselquist
Lisbet H Bach
Kristin Palmqvist
Michael J Gundale
Source
Glob Chang Biol. 2015 Aug;21(8):3169-80
Date
Aug-2015
Language
English
Publication Type
Article
Keywords
Carbon - analysis
Carbon Sequestration
Ecosystem
Nitrogen - analysis
Soil - chemistry
Soil Microbiology
Sweden
Taiga
Abstract
It is proposed that carbon (C) sequestration in response to reactive nitrogen (Nr ) deposition in boreal forests accounts for a large portion of the terrestrial sink for anthropogenic CO2 emissions. While studies have helped clarify the magnitude by which Nr deposition enhances C sequestration by forest vegetation, there remains a paucity of long-term experimental studies evaluating how soil C pools respond. We conducted a long-term experiment, maintained since 1996, consisting of three N addition levels (0, 12.5, and 50 kg N ha(-1) yr(-1) ) in the boreal zone of northern Sweden to understand how atmospheric Nr deposition affects soil C accumulation, soil microbial communities, and soil respiration. We hypothesized that soil C sequestration will increase, and soil microbial biomass and soil respiration will decrease, with disproportionately large changes expected compared to low levels of N addition. Our data showed that the low N addition treatment caused a non-significant increase in the organic horizon C pool of ~15% and a significant increase of ~30% in response to the high N treatment relative to the control. The relationship between C sequestration and N addition in the organic horizon was linear, with a slope of 10 kg C kg(-1) N. We also found a concomitant decrease in total microbial and fungal biomasses and a ~11% reduction in soil respiration in response to the high N treatment. Our data complement previous data from the same study system describing aboveground C sequestration, indicating a total ecosystem sequestration rate of 26 kg C kg(-1) N. These estimates are far lower than suggested by some previous modeling studies, and thus will help improve and validate current modeling efforts aimed at separating the effect of multiple global change factors on the C balance of the boreal region.
PubMed ID
25711504 View in PubMed
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Applying a framework for landscape planning under climate change for the conservation of biodiversity in the Finnish boreal forest.

https://arctichealth.org/en/permalink/ahliterature267267
Source
Glob Chang Biol. 2015 Feb;21(2):637-51
Publication Type
Article
Date
Feb-2015
Author
Adriano Mazziotta
Maria Triviño
Olli-Pekka Tikkanen
Jari Kouki
Harri Strandman
Mikko Mönkkönen
Source
Glob Chang Biol. 2015 Feb;21(2):637-51
Date
Feb-2015
Language
English
Publication Type
Article
Keywords
Biodiversity
Climate change
Conservation of Natural Resources - methods
Finland
Models, Biological
Taiga
Trees - physiology
Abstract
Conservation strategies are often established without consideration of the impact of climate change. However, this impact is expected to threaten species and ecosystem persistence and to have dramatic effects towards the end of the 21st century. Landscape suitability for species under climate change is determined by several interacting factors including dispersal and human land use. Designing effective conservation strategies at regional scales to improve landscape suitability requires measuring the vulnerabilities of specific regions to climate change and determining their conservation capacities. Although methods for defining vulnerability categories are available, methods for doing this in a systematic, cost-effective way have not been identified. Here, we use an ecosystem model to define the potential resilience of the Finnish forest landscape by relating its current conservation capacity to its vulnerability to climate change. In applying this framework, we take into account the responses to climate change of a broad range of red-listed species with different niche requirements. This framework allowed us to identify four categories in which representation in the landscape varies among three IPCC emission scenarios (B1, low; A1B, intermediate; A2, high emissions): (i) susceptible (B1 = 24.7%, A1B = 26.4%, A2 = 26.2%), the most intact forest landscapes vulnerable to climate change, requiring management for heterogeneity and resilience; (ii) resilient (B1 = 2.2%, A1B = 0.5%, A2 = 0.6%), intact areas with low vulnerability that represent potential climate refugia and require conservation capacity maintenance; (iii) resistant (B1 = 6.7%, A1B = 0.8%, A2 = 1.1%), landscapes with low current conservation capacity and low vulnerability that are suitable for restoration projects; (iv) sensitive (B1 = 66.4%, A1B = 72.3%, A2 = 72.0%), low conservation capacity landscapes that are vulnerable and for which alternative conservation measures are required depending on the intensity of climate change. Our results indicate that the Finnish landscape is likely to be dominated by a very high proportion of sensitive and susceptible forest patches, thereby increasing uncertainty for landscape managers in the choice of conservation strategies.
Notes
Erratum In: Glob Chang Biol. 2015 Sep;21(9):319326386356
PubMed ID
25044467 View in PubMed
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Source
Science. 2015 Dec 4;350(6265):1148-51
Publication Type
Article
Date
Dec-4-2015
Author
Eli Kintisch
Source
Science. 2015 Dec 4;350(6265):1148-51
Date
Dec-4-2015
Language
English
Publication Type
Article
Keywords
Animals
Bison
Conservation of Natural Resources
Herbivory
Parks, Recreational
Permafrost
Siberia
Taiga
PubMed ID
26785455 View in PubMed
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Can Siberian alder N-fixation offset N-loss after severe fire? Quantifying post-fire Siberian alder distribution, growth, and N-fixation in boreal Alaska.

https://arctichealth.org/en/permalink/ahliterature304854
Source
PLoS One. 2020; 15(9):e0238004
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Date
2020
Author
Brian Houseman
Roger Ruess
Teresa Hollingsworth
Dave Verbyla
Author Affiliation
Institute of Arctic Biology, University of Alaska, Fairbanks, Alaska, United States of America.
Source
PLoS One. 2020; 15(9):e0238004
Date
2020
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Keywords
Alaska
Alnus - growth & development - metabolism
Ecosystem
Fires
Nitrogen - analysis - metabolism
Nitrogen Fixation
Taiga
Trees - growth & development - metabolism
Abstract
Fire severity affects both ecosystem N-loss and post-fire N-balance. Climate change is altering the fire regime of interior Alaska, although the effects on Siberian alder (Alnus viridis ssp. fruticosa) annual N-fixation input (kg N ha-1 yr-1) and ecosystem N-balance are largely unknown. We established 263 study plots across two burn scars within the Yukon-Tanana Uplands ecoregion of interior Alaska. Siberian alder N-input was quantified by post-fire age, fire severity, and stand type. We modeled the components of Siberian alder N-input using environmental variables and fire severity within and across burn scars and estimated post-fire N-balance using N-loss (volatilized N) and N-gain [biological N-fixation and atmospheric deposition]. Mean nodule-level N-fixation rate was 70% higher 11-years post-fire (12.88 ± 1.18 µmol N g-1 hr-1) than 40-years post-fire (7.58 ± 0.59 µmol N g-1 hr-1). Structural equation modeling indicated that fire severity had a negative effect on Siberian alder density, but a positive effect on live nodule biomass (g nodule m-2 plant-1). Post-fire Siberian alder N-input was highest in 11-year old moderately burned deciduous stands (11.53 ± 0.22 kg N ha-1 yr-1), and lowest in 11-year old stands that converted from black spruce to deciduous dominance after severe fire (0.06 ± 0.003 kg N ha-1 yr-1). Over a 138-year fire return interval, N-gains in converted black spruce stands are estimated to offset 15% of volatilized N, whereas N-gains in burned deciduous stands likely exceed volatilized N by an order of magnitude. High Siberian alder density and nodule biomass drives N-input in burned deciduous stands, while low N-fixer density (including Siberian alder) limits N-input in high severity black spruce stands not underlain by permafrost. A severe fire regime that converts black spruce stands to deciduous dominance without alder recruitment may induce progressive N-losses which alter boreal forest ecosystem patterns and processes.
PubMed ID
32877417 View in PubMed
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Carbon sequestration is related to mycorrhizal fungal community shifts during long-term succession in boreal forests.

https://arctichealth.org/en/permalink/ahliterature266720
Source
New Phytol. 2015 Mar;205(4):1525-36
Publication Type
Article
Date
Mar-2015
Author
Karina E Clemmensen
Roger D Finlay
Anders Dahlberg
Jan Stenlid
David A Wardle
Björn D Lindahl
Source
New Phytol. 2015 Mar;205(4):1525-36
Date
Mar-2015
Language
English
Publication Type
Article
Keywords
Biodiversity
Carbon Sequestration
Ecosystem
Islands
Models, Biological
Mycorrhizae - physiology
Phylogeny
Species Specificity
Sweden
Taiga
Time Factors
Abstract
Boreal forest soils store a major proportion of the global terrestrial carbon (C) and below-ground inputs contribute as much as above-ground plant litter to the total C stored in the soil. A better understanding of the dynamics and drivers of root-associated fungal communities is essential to predict long-term soil C storage and climate feedbacks in northern ecosystems. We used 454-pyrosequencing to identify fungal communities across fine-scaled soil profiles in a 5000 yr fire-driven boreal forest chronosequence, with the aim of pinpointing shifts in fungal community composition that may underlie variation in below-ground C sequestration. In early successional-stage forests, higher abundance of cord-forming ectomycorrhizal fungi (such as Cortinarius and Suillus species) was linked to rapid turnover of mycelial biomass and necromass, efficient nitrogen (N) mobilization and low C sequestration. In late successional-stage forests, cord formers declined, while ericoid mycorrhizal ascomycetes continued to dominate, potentially facilitating long-term humus build-up through production of melanized hyphae that resist decomposition. Our results suggest that cord-forming ectomycorrhizal fungi and ericoid mycorrhizal fungi play opposing roles in below-ground C storage. We postulate that, by affecting turnover and decomposition of fungal tissues, mycorrhizal fungal identity and growth form are critical determinants of C and N sequestration in boreal forests.
Notes
Comment In: New Phytol. 2015 Mar;205(4):1378-8025645716
PubMed ID
25494880 View in PubMed
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Chronic Nitrogen Deposition Has a Minor Effect on the Quantity and Quality of Aboveground Litter in a Boreal Forest.

https://arctichealth.org/en/permalink/ahliterature285257
Source
PLoS One. 2016;11(8):e0162086
Publication Type
Article
Date
2016
Author
Nadia I Maaroufi
Annika Nordin
Kristin Palmqvist
Michael J Gundale
Source
PLoS One. 2016;11(8):e0162086
Date
2016
Language
English
Publication Type
Article
Keywords
Bryophyta - chemistry - physiology
Carbon - analysis
Ecosystem
Nitrogen - analysis
Soil - chemistry
Sweden
Taiga
Abstract
There is evidence that anthropogenic nitrogen (N) deposition enhances carbon (C) sequestration in boreal soils. However, key underlying mechanisms explaining this increase have not been resolved. Two potentially important mechanisms are that aboveground litter production increases, or that litter quality changes in response to N enrichment. As such, our aim was to quantify whether simulated chronic N deposition caused changes in aboveground litter production or quality in a boreal forest. We conducted a long-term (17 years) stand-scale (0.1 ha) forest experiment, consisting of three N addition levels (0, 12.5, and 50 kg N ha-1 yr-1) in northern Sweden, where background N deposition rates are very low. We measured the annual quantity of litter produced for 8 different litter categories, as well as their concentrations of C, N, phosphorus (P), lignin, cellulose and hemi-cellulose. Our results indicate that mosses were the only major litter component showing significant quantitative and qualitative alterations in response to the N additions, indicative of their ability to intercept a substantial portion of the N added. These effects were, however, offset by the other litter fractions where we found no changes in the total litter fluxes, or individual chemical constituents when all litter categories were summed. This study indicates that the current annual litter fluxes cannot explain the increase in soil C that has occurred in our study system in response to simulated chronic N application. These results suggest that other mechanisms are likely to explain the increased soil C accumulation rate we have observed, such as changes in soil microbial activity, or potentially transient changes in aboveground litter inputs that were no longer present at the time of our study.
Notes
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PubMed ID
27580120 View in PubMed
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Climate change and bird reproduction: warmer springs benefit breeding success in boreal forest grouse.

https://arctichealth.org/en/permalink/ahliterature292089
Source
Proc Biol Sci. 2017 Nov 15; 284(1866):
Publication Type
Journal Article
Date
Nov-15-2017
Author
Per Wegge
Jørund Rolstad
Author Affiliation
Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003 NMBU, 1432, Ås, Norway per.wegge@nmbu.no.
Source
Proc Biol Sci. 2017 Nov 15; 284(1866):
Date
Nov-15-2017
Language
English
Publication Type
Journal Article
Keywords
Animals
Climate change
Female
Galliformes - physiology
Global warming
Norway
Reproduction
Seasons
Species Specificity
Taiga
Temperature
Abstract
Global warming is predicted to adversely affect the reproduction of birds, especially in northern latitudes. A recent study in Finland inferred that declining populations of black grouse, Tetrao tetrix, could be attributed to advancement of the time of mating and chicks hatching too early-supporting the mismatch hypothesis. Here, we examine the breeding success of sympatric capercaillie, T. urogallus, and black grouse over a 38-year period in southeast Norway. Breeding season temperatures increased, being most pronounced in April. Although the onset of spring advanced nearly three weeks, the peak of mating advanced only 4-5 days. In contrast to the result of the Finnish study, breeding success increased markedly in both species (capercaillie: 62%, black grouse: 38%). Both brood frequency and brood size increased during the study period, but significantly so only for brood frequency in capercaillie. Whereas the frequency of capercaillie broods was positively affected by rising temperatures, especially during the pre-hatching period, this was not the case in black grouse. Brood size, on the other hand, increased with increasing post-hatching temperatures in both species. Contrary to the prediction that global warming will adversely affect reproduction in boreal forest grouse, our study shows that breeding success was enhanced in warmer springs.
Notes
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PubMed ID
29118133 View in PubMed
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Climate change induces multiple risks to boreal forests and forestry in Finland: A literature review.

https://arctichealth.org/en/permalink/ahliterature305800
Source
Glob Chang Biol. 2020 08; 26(8):4178-4196
Publication Type
Journal Article
Review
Date
08-2020
Author
Ari Venäläinen
Ilari Lehtonen
Mikko Laapas
Kimmo Ruosteenoja
Olli-Pekka Tikkanen
Heli Viiri
Veli-Pekka Ikonen
Heli Peltola
Author Affiliation
Finnish Meteorological Institute, Helsinki, Finland.
Source
Glob Chang Biol. 2020 08; 26(8):4178-4196
Date
08-2020
Language
English
Publication Type
Journal Article
Review
Keywords
Animals
Climate change
Ecosystem
Finland
Forestry
Forests
Norway
Taiga
Abstract
Climate change induces multiple abiotic and biotic risks to forests and forestry. Risks in different spatial and temporal scales must be considered to ensure preconditions for sustainable multifunctional management of forests for different ecosystem services. For this purpose, the present review article summarizes the most recent findings on major abiotic and biotic risks to boreal forests in Finland under the current and changing climate, with the focus on windstorms, heavy snow loading, drought and forest fires and major insect pests and pathogens of trees. In general, the forest growth is projected to increase mainly in northern Finland. In the south, the growing conditions may become suboptimal, particularly for Norway spruce. Although the wind climate does not change remarkably, wind damage risk will increase especially in the south, because of the shortening of the soil frost period. The risk of snow damage is anticipated to increase in the north and decrease in the south. Increasing drought in summer will boost the risk of large-scale forest fires. Also, the warmer climate increases the risk of bark beetle outbreaks and the wood decay by Heterobasidion root rot in coniferous forests. The probability of detrimental cascading events, such as those caused by a large-scale wind damage followed by a widespread bark beetle outbreak, will increase remarkably in the future. Therefore, the simultaneous consideration of the biotic and abiotic risks is essential.
PubMed ID
32449267 View in PubMed
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75 records – page 1 of 8.