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Henriksson N, Marshall J, Högberg MN, Högberg P, Polle A, Franklin O, Näsholm T. Re-examining the evidence for the mother tree hypothesis - resource sharing among trees via ectomycorrhizal networks. THE NEW PHYTOLOGIST 2023. [PMID: 37149889 DOI: 10.1111/nph.18935] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 03/19/2023] [Indexed: 05/09/2023]
Abstract
Seminal scientific papers positing that mycorrhizal fungal networks can distribute carbon (C) among plants have stimulated a popular narrative that overstory trees, or 'mother trees', support the growth of seedlings in this way. This narrative has far-reaching implications for our understanding of forest ecology and has been controversial in the scientific community. We review the current understanding of ectomycorrhizal C metabolism and observations on forest regeneration that make the mother tree narrative debatable. We then re-examine data and conclusions from publications that underlie the mother tree hypothesis. Isotopic labeling methods are uniquely suited for studying element fluxes through ecosystems, but the complexity of mycorrhizal symbiosis, low detection limits, and small carbon discrimination in biological processes can cause researchers to make important inferences based on miniscule shifts in isotopic abundance, which can be misleading. We conclude that evidence of a significant net C transfer via common mycorrhizal networks that benefits the recipients is still lacking. Furthermore, a role for fungi as a C pipeline between trees is difficult to reconcile with any adaptive advantages for the fungi. Finally, the hypothesis is neither supported by boreal forest regeneration patterns nor consistent with the understanding of physiological mechanisms controlling mycorrhizal symbiosis.
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Affiliation(s)
- Nils Henriksson
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
| | - John Marshall
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
| | - Mona N Högberg
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
| | - Peter Högberg
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
| | - Andrea Polle
- Forest Botany and Tree Physiology, Georg-August University of Göttingen, Büsgenweg 2, 37077, Göttingen, Germany
| | - Oskar Franklin
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
- International Institute for Applied Systems Analysis, Schlossplatz 1, Laxenburg, A-2361, Austria
| | - Torgny Näsholm
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden
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Zhou Y, Yang M, Tai Z, Jia J, Luan D, Ma X. Carbohydrates and secondary compounds of alpine tundra shrubs in relation to experimental warming. BMC PLANT BIOLOGY 2022; 22:482. [PMID: 36210454 PMCID: PMC9549620 DOI: 10.1186/s12870-022-03851-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND It is critical to understand the sensitivity, response direction and magnitude of carbohydrates and secondary compounds to warming for predicting the structure and function of the tundra ecosystem towards future climate change. RESULTS Open-top chambers (OTCs) were used to passively increase air and soil temperatures on Changbai Mountain alpine tundra. After seven years' continuous warming (+ 1.5 °C), the vegetation coverage, nonstructural carbohydrates (soluble sugars and starch) and secondary compounds (total phenols, flavonoids and triterpenes) of leaves and roots in three dominant dwarf shrubs, Dryas octopetala var. asiatica, Rhododendron confertissimum and Vaccinium uliginosum, were investigated during the growing season. Warming did not significantly affect the concentrations of carbohydrates but decreased total phenols for the three species. Carbohydrates and secondary compounds showed significantly seasonal pattern and species-specific variation. No significant trade-off or negative relationship between carbohydrates and secondary compounds was observed. Compared to Dr. octopetala var. asiatica, V. uliginosum allocated more carbon on secondary compounds. Warming significantly increased the coverage of Dr. octopetala var. asiatica, did not change it for V. uliginosum and decreased it for Rh. confertissimum. Rh. confertissimum had significantly lower carbohydrates and invested more carbon on secondary compounds than the other two species. CONCLUSIONS Enhanced dominance and competitiveness of Dr. octopetala var. asiatica was companied by increased trend in carbohydrate concentrations and decreased ratio of secondary compounds to total carbon in the warming OTCs. We, therefore, predict that Dr. octopetala var. asiatica will continue to maintain dominant status, but the competition ability of V. uliginosum could gradually decrease with warming, leading to changes in species composition and community structure of the Changbai tundra ecosystem under future climate warming.
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Affiliation(s)
- Yumei Zhou
- Ecological Technique and Engineering School, Shanghai Institute of Technology, Shanghai, 201418, China
| | - Ming Yang
- Ecological Technique and Engineering School, Shanghai Institute of Technology, Shanghai, 201418, China
| | - Zhijuan Tai
- Department of Tourism Economy, Changbai Mountain Academy of Sciences, Baihe, 133633, China
| | - Jingjing Jia
- Ecological Technique and Engineering School, Shanghai Institute of Technology, Shanghai, 201418, China
| | - Dongtao Luan
- Ecological Technique and Engineering School, Shanghai Institute of Technology, Shanghai, 201418, China
| | - Xia Ma
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Shanghai, 201418, China.
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Heckford TR, Leroux SJ, Vander Wal E, Rizzuto M, Balluffi‐Fry J, Richmond IC, Wiersma YF. Ecoregion and community structure influences on the foliar elemental niche of balsam fir ( Abies balsamea (L.) Mill.) and white birch ( Betula papyrifera Marshall). Ecol Evol 2022; 12:e9244. [PMID: 36110871 PMCID: PMC9465200 DOI: 10.1002/ece3.9244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 06/18/2022] [Accepted: 08/01/2022] [Indexed: 11/14/2022] Open
Abstract
Changes in foliar elemental niche properties, defined by axes of carbon (C), nitrogen (N), and phosphorus (P) concentrations, reflect how species allocate resources under different environmental conditions. For instance, elemental niches may differ in response to large-scale latitudinal temperature and precipitation regimes that occur between ecoregions and small-scale differences in nutrient dynamics based on species co-occurrences at a community level. At a species level, we compared foliar elemental niche hypervolumes for balsam fir (Abies balsamea (L.) Mill.) and white birch (Betula papyrifera Marshall) between a northern and southern ecoregion. At a community level, we grouped our focal species using plot data into conspecific (i.e., only one focal species is present) and heterospecific groups (i.e., both focal species are present) and compared their foliar elemental concentrations under these community conditions across, within, and between these ecoregions. Between ecoregions at the species and community level, we expected niche hypervolumes to be different and driven by regional biophysical effects on foliar N and P concentrations. At the community level, we expected niche hypervolume displacement and expansion patterns for fir and birch, respectively-patterns that reflect their resource strategy. At the species level, foliar elemental niche hypervolumes between ecoregions differed significantly for fir (F = 14.591, p-value = .001) and birch (F = 75.998, p-value = .001) with higher foliar N and P in the northern ecoregion. At the community level, across ecoregions, the foliar elemental niche hypervolume of birch differed significantly between heterospecific and conspecific groups (F = 4.075, p-value = .021) but not for fir. However, both species displayed niche expansion patterns, indicated by niche hypervolume increases of 35.49% for fir and 68.92% for birch. Within the northern ecoregion, heterospecific conditions elicited niche expansion responses, indicated by niche hypervolume increases for fir of 29.04% and birch of 66.48%. In the southern ecoregion, we observed a contraction response for birch (niche hypervolume decreased by 3.66%) and no changes for fir niche hypervolume. Conspecific niche hypervolume comparisons between ecoregions yielded significant differences for fir and birch (F = 7.581, p-value = .005 and F = 8.038, p-value = .001) as did heterospecific comparisons (F = 6.943, p-value = .004, and F = 68.702, p-value = .001, respectively). Our results suggest species may exhibit biogeographical specific elemental niches-driven by biophysical differences such as those used to describe ecoregion characteristics. We also demonstrate how a species resource strategy may inform niche shift patterns in response to different community settings. Our study highlights how biogeographical differences may influence foliar elemental traits and how this may link to concepts of ecosystem and landscape functionality.
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Affiliation(s)
- Travis R. Heckford
- British Columbia GovernmentMinistry of Forests, Cariboo Natural Resource RegionWilliams LakeBritish ColumbiaCanada
| | - Shawn J. Leroux
- Department of BiologyMemorial University of NewfoundlandSt. John'sNewfoundland and LabradorCanada
| | - Eric Vander Wal
- Department of BiologyMemorial University of NewfoundlandSt. John'sNewfoundland and LabradorCanada
| | - Matteo Rizzuto
- Department of BiologyMemorial University of NewfoundlandSt. John'sNewfoundland and LabradorCanada
| | - Juliana Balluffi‐Fry
- Department of BiologyMemorial University of NewfoundlandSt. John'sNewfoundland and LabradorCanada
| | - Isabella C. Richmond
- Department of BiologyMemorial University of NewfoundlandSt. John'sNewfoundland and LabradorCanada
| | - Yolanda F. Wiersma
- Department of BiologyMemorial University of NewfoundlandSt. John'sNewfoundland and LabradorCanada
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Authier L, Violle C, Richard F. Ectomycorrhizal Networks in the Anthropocene: From Natural Ecosystems to Urban Planning. FRONTIERS IN PLANT SCIENCE 2022; 13:900231. [PMID: 35845640 PMCID: PMC9280895 DOI: 10.3389/fpls.2022.900231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
Trees acquire hydric and mineral soil resources through root mutualistic associations. In most boreal, temperate and Mediterranean forests, these functions are realized by a chimeric structure called ectomycorrhizae. Ectomycorrhizal (ECM) fungi are highly diversified and vary widely in their specificity toward plant hosts. Reciprocally, association patterns of ECM plants range from highly specialist to generalist. As a consequence, ECM symbiosis creates interaction networks, which also mediate plant-plant nutrient interactions among different individuals and drive plant community dynamics. Our knowledge of ECM networks essentially relies on a corpus acquired in temperate ecosystems, whereas the below-ground facets of both anthropogenic ECM forests and inter-tropical forests remain poorly investigated. Here, we successively (1) review the current knowledge of ECM networks, (2) examine the content of early literature produced in ECM cultivated forests, (3) analyze the recent progress that has been made in understanding the place of ECM networks in urban soils, and (4) provide directions for future research based on the identification of knowledge gaps. From the examined corpus of knowledge, we reach three main conclusions. First, the emergence of metabarcoding tools has propelled a resurgence of interest in applying network theory to ECM symbiosis. These methods revealed an unexpected interconnection between mutualistic plants with arbuscular mycorrhizal (AM) herbaceous plants, embedding ECM mycelia through root-endophytic interactions. This affinity of ECM fungi to bind VA and ECM plants, raises questions on the nature of the associated functions. Second, despite the central place of ECM trees in cultivated forests, little attention has been paid to these man-made landscapes and in-depth research on this topic is lacking. Third, we report a lag in applying the ECM network theory to urban soils, despite management initiatives striving to interconnect motile organisms through ecological corridors, and the highly challenging task of interconnecting fixed organisms in urban greenspaces is discussed. In particular, we observe a pauperized nature of resident ECM inoculum and a spatial conflict between belowground human pipelines and ECM networks. Finally, we identify the main directions of future research to make the needed link between the current picture of plant functioning and the understanding of belowground ECM networks.
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Affiliation(s)
- Louise Authier
- CEFE, Univ Montpellier - CNRS - EPHE - IRD, Montpellier, France
- Ilex Paysage + Urbanisme, Lyon, France
| | - Cyrille Violle
- CEFE, Univ Montpellier - CNRS - EPHE - IRD, Montpellier, France
| | - Franck Richard
- CEFE, Univ Montpellier - CNRS - EPHE - IRD, Montpellier, France
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Spitzer CM, Sundqvist MK, Wardle DA, Gundale MJ, Kardol P. Root trait variation along a sub‐arctic tundra elevational gradient. OIKOS 2022. [DOI: 10.1111/oik.08903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Clydecia M. Spitzer
- Dept of Forest Ecology and Management, Swedish Univ. of Agricultural Sciences Umeå Sweden
| | - Maja K. Sundqvist
- Dept of Forest Ecology and Management, Swedish Univ. of Agricultural Sciences Umeå Sweden
| | - David A. Wardle
- Asian School of the Environment, Nanyang Technological Univ. Singapore Singapore
| | - Michael J. Gundale
- Dept of Forest Ecology and Management, Swedish Univ. of Agricultural Sciences Umeå Sweden
| | - Paul Kardol
- Dept of Forest Ecology and Management, Swedish Univ. of Agricultural Sciences Umeå Sweden
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Khan NF, Reshi ZA. Diversity of root-associated mycobiome of Betula utilis D. Don: a treeline species in Kashmir Himalaya. Trop Ecol 2022. [DOI: 10.1007/s42965-022-00230-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Heim RJ, Heim W, Bültmann H, Kamp J, Rieker D, Yurtaev A, Hölzel N. Fire disturbance promotes biodiversity of plants, lichens and birds in the Siberian subarctic tundra. GLOBAL CHANGE BIOLOGY 2022; 28:1048-1062. [PMID: 34706133 DOI: 10.1111/gcb.15963] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 10/06/2021] [Indexed: 06/13/2023]
Abstract
Fire shapes the world's terrestrial ecosystems and has been influencing biodiversity patterns for millennia. Anthropogenic drivers alter fire regimes. Wildfires can amplify changes in the structure, biodiversity and functioning of the fast-warming tundra ecosystem. However, there is little evidence available, how these fires affect species diversity and community composition of tundra ecosystems over the long term. We studied long-term fire effects on community composition and diversity at different trophic levels of the food web in the subarctic tundra of Western Siberia. In a space-for-time approach we compared three large fire scars (>44, 28 and 12 years old) to unburnt controls. We found that diversity (measured as species richness, Shannon index and evenness) of vascular and non-vascular plants and birds was strongly affected by fire, with the greatest species richness of plants and birds for the intermediate-age fire scar (28 years). Species composition of plants and birds still differed from that of the control >44 years after fire. Increased deciduous shrub cover was related to species richness of all plants in a hump-shaped manner. The proportion of southern (taiga) bird species was highest in the oldest fire scar, which had the highest shrub cover. We conclude that tundra fires have long-term legacies with regard to species diversity and community composition. They may also increase landscape-scale species richness and facilitate range expansions of more southerly distributed species to the subarctic tundra ecosystem.
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Affiliation(s)
- Ramona J Heim
- Institute of Landscape Ecology, University of Münster, Münster, Germany
| | - Wieland Heim
- Institute of Landscape Ecology, University of Münster, Münster, Germany
- Department of Biology, University of Turku, Turku, Finland
| | - Helga Bültmann
- Institute of Landscape Ecology, University of Münster, Münster, Germany
| | - Johannes Kamp
- Department of Conservation Biology, University of Göttingen, Göttingen, Germany
| | - Daniel Rieker
- Institute for Ecology, Evolution and Diversity, Goethe University Frankfurt, Frankfurt, Germany
| | - Andrey Yurtaev
- Research Institute of Ecology and Natural Resources Management, Tyumen State University, Tyumen, Russia
| | - Norbert Hölzel
- Institute of Landscape Ecology, University of Münster, Münster, Germany
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9
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Martin AC, Macias-Fauria M, Bonsall MB, Forbes BC, Zetterberg P, Jeffers ES. Common mechanisms explain nitrogen-dependent growth of Arctic shrubs over three decades despite heterogeneous trends and declines in soil nitrogen availability. THE NEW PHYTOLOGIST 2022; 233:670-686. [PMID: 34087005 DOI: 10.1111/nph.17529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 05/20/2021] [Indexed: 06/12/2023]
Abstract
Heterogeneity has been observed in the responses of Arctic shrubs to climate variability over recent decades, which may reflect landscape-scale variability in belowground resources. At a northern fringe of tall shrub expansion (Yuribei, Yamal Peninsula, Russia), we sought to determine the mechanisms relating nitrogen (N) limitation to shrub growth over decadal time. We analysed the ratio of 15 N to 14 N isotopes in wood rings of 10 Salix lanata individuals (399 measurements) to reconstruct annual point-based bioavailable N between 1980 and 2013. We applied a model-fitting/model-selection approach with a suite of competing ecological models to assess the most-likely mechanisms that explain each shrub's individual time-series. Shrub δ15 N time-series indicated declining (seven shrubs), increasing (two shrubs) and no trend (one shrub) in N availability. The most appropriate model for all shrubs included N-dependent growth of linear rather than saturating form. Inclusion of plant-soil feedbacks better explained ring width and δ15 N for eight of 10 individuals. Although N trajectories were individualistic, common mechanisms of varying strength confirmed the N-dependency of shrub growth. The linear mechanism may reflect intense scavenging of scarce N; the importance of plant-soil feedbacks suggests that shrubs subvert the microbial bottleneck by actively controlling their environment.
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Affiliation(s)
- Andrew C Martin
- Oxford Long-Term Ecology Laboratory, Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK
- Biogeosciences Lab, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK
| | - Marc Macias-Fauria
- Biogeosciences Lab, School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK
| | - Michael B Bonsall
- Mathematical Ecology Research Group, Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK
| | - Bruce C Forbes
- Arctic Centre, University of Lapland, Pohjoisranta 4, Rovaniemi, 96100, Finland
| | - Pentti Zetterberg
- Department of Forest Sciences, University of Eastern Finland, Joensuu, 80101, Finland
| | - Elizabeth S Jeffers
- Oxford Long-Term Ecology Laboratory, Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK
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Biophysical Determinants of Shifting Tundra Vegetation Productivity in the Beaufort Delta Region of Canada. Ecosystems 2022. [DOI: 10.1007/s10021-021-00725-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractTemperature increases across the circumpolar north have driven rapid increases in vegetation productivity, often described as ‘greening’. These changes have been widespread, but spatial variation in their pattern and magnitude suggests that biophysical factors also influence the response of tundra vegetation to climate warming. In this study, we used field sampling of soils and vegetation and random forests modeling to identify the determinants of trends in Landsat-derived Enhanced Vegetation Index, a surrogate for productivity, in the Beaufort Delta region of Canada between 1984 and 2016. This region has experienced notable change, with over 71% of the Tuktoyaktuk Coastlands and over 66% of the Yukon North Slope exhibiting statistically significant greening. Using both classification and regression random forests analyses, we show that increases in productivity have been more widespread and rapid at low-to-moderate elevations and in areas dominated by till blanket and glaciofluvial deposits, suggesting that nutrient and moisture availability mediate the impact of climate warming on tundra vegetation. Rapid greening in shrub-dominated vegetation types and observed increases in the cover of low and tall shrub cover (4.8% and 6.0%) also indicate that regional changes have been driven by shifts in the abundance of these functional groups. Our findings demonstrate the utility of random forests models for identifying regional drivers of tundra vegetation change. To obtain additional fine-grained insights on drivers of increased tundra productivity, we recommend future research combine spatially comprehensive time series satellite data (as used herein) with samples of high spatial resolution imagery and integrated field investigations.
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Figueiredo AF, Boy J, Guggenberger G. Common Mycorrhizae Network: A Review of the Theories and Mechanisms Behind Underground Interactions. FRONTIERS IN FUNGAL BIOLOGY 2021; 2:735299. [PMID: 37744156 PMCID: PMC10512311 DOI: 10.3389/ffunb.2021.735299] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 08/23/2021] [Indexed: 09/26/2023]
Abstract
Most terrestrial plants establish symbiotic associations with mycorrhizal fungi for accessing essential plant nutrients. Mycorrhizal fungi have been frequently reported to interconnect plants via a common mycelial network (CMN), in which nutrients and signaling compounds can be exchanged between the connected plants. Several studies have been performed to demonstrate the potential effects of the CMN mediating resource transfer and its importance for plant fitness. Due to several contrasting results, different theories have been developed to predict benefits or disadvantages for host plants involved in the network and how it might affect plant communities. However, the importance of the mycelium connections for resources translocation compared to other indirect pathways, such as leakage of fungi hyphae and subsequent uptake by neighboring plant roots, is hard to distinguish and quantify. If resources can be translocated via mycelial connections in significant amounts that could affect plant fitness, it would represent an important tactic for plants co-existence and it could shape community composition and dynamics. Here, we report and critically discuss the most recent findings on studies aiming to evaluate and quantify resources translocation between plants sharing a CMN and predict the pattern that drives the movement of such resources into the CMN. We aim to point gaps and define open questions to guide upcoming studies in the area for a prospect better understanding of possible plant-to-plant interactions via CMN and its effect in shaping plants communities. We also propose new experiment set-ups and technologies that could be used to improve previous experiments. For example, the use of mutant lines plants with manipulation of genes involved in the symbiotic associations, coupled with labeling techniques to track resources translocation between connected plants, could provide a more accurate idea about resource allocation and plant physiological responses that are truly accountable to CMN.
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Noffsinger C, Cripps CL. Systematic analysis of Russula in the North American Rocky Mountain alpine zone. Mycologia 2021; 113:1278-1315. [PMID: 34477492 DOI: 10.1080/00275514.2021.1947695] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Russula (Russulales) is an important ectomycorrhizal fungal genus in Arctic and alpine regions where it occurs with Salix, Betula, Dryas, and Polygonum, yet a complex phylogenetic analysis of the genus in these habitats is lacking. This research compared collections of Russula from the Rocky Mountain alpine (Colorado, Montana, Wyoming) with reference specimens from Arctic and alpine habitats, mostly in Europe, using an in-depth morphological study and a phylogenetic analysis of the nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS barcode) and the second largest subunit of the RNA polymerase II gene (rpb2). One hundred thirty-nine Russula collections were sequenced, including type material. Ten species are reported from alpine or treeline habitats in the Rocky Mountains. This is the first formal report of R. cf. altaica, R. saliceticola, and R. subrubens from the Rocky Mountains and of R. purpureofusca in North America. Russula laevis is reported for the first time under this name with a voucher, and not as an environmental sample. Previous reports of R. nana and R. laccata are molecularly confirmed. Two species are reported from subalpine habitats at treeline: R. montana with conifers and R. cf. altaica with Betula. In this study, R. laccata, R. subrubens, and R. laevis were collected in alpine habitats but have been reported below treeline in Europe; these species may also be present at lower elevations in North America. Most species have an intercontinental distribution and have been reported in other alpine or Arctic habitats. Two unidentified and potentially new species were only found in North America and are discussed. A key to the alpine Russulas of North America is provided.
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Affiliation(s)
- Chance Noffsinger
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, Montana 59717
| | - Cathy L Cripps
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, Montana 59717
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Heim RJ, Bucharova A, Brodt L, Kamp J, Rieker D, Soromotin AV, Yurtaev A, Hölzel N. Post-fire vegetation succession in the Siberian subarctic tundra over 45 years. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 760:143425. [PMID: 33172629 DOI: 10.1016/j.scitotenv.2020.143425] [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: 07/28/2020] [Revised: 10/28/2020] [Accepted: 10/28/2020] [Indexed: 06/11/2023]
Abstract
Wildfires are relatively rare in subarctic tundra ecosystems, but they can strongly change ecosystem properties. Short-term fire effects on subarctic tundra vegetation are well documented, but long-term vegetation recovery has been studied less. The frequency of tundra fires will increase with climate warming. Understanding the long-term effects of fire is necessary to predict future ecosystem changes. We used a space-for-time approach to assess vegetation recovery after fire over more than four decades. We studied soil and vegetation patterns on three large fire scars (>44, 28 and 12 years old) in dry, lichen-dominated forest tundra in Western Siberia. On 60 plots, we determined soil temperature and permafrost thaw depth, sampled vegetation and measured plant functional traits. We assessed trends in Normalized Difference Vegetation Index (NDVI) to support the field-based results on vegetation recovery. Soil temperature, permafrost thaw depth and total vegetation cover had recovered to pre-fire levels after >44 years, as well as total vegetation cover. In contrast, after >44 years, functional groups had not recovered to the pre-fire state. Burnt areas had lower lichen and higher bryophyte and shrub cover. The dominating shrub species, Betula nana, exhibited a higher vitality (higher specific leaf area and plant height) on burnt compared with control plots, suggesting a fire legacy effect in shrub growth. Our results confirm patterns of shrub encroachment after fire that were detected before in other parts of the Arctic and Subarctic. In the so far poorly studied Western Siberian forest tundra we demonstrate for the first time, long-term fire-legacies on the functional composition of relatively dry shrub- and lichen-dominated vegetation.
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Affiliation(s)
- Ramona J Heim
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany.
| | - Anna Bucharova
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany
| | - Leya Brodt
- Research Institute of Ecology and Natural Resources Management, Tyumen State University, 6 Volodarskogo Street, Tyumen, Russia
| | - Johannes Kamp
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany; Department of Conservation Biology, University of Göttingen, Bürgerstr. 50, 37073 Göttingen, Germany
| | - Daniel Rieker
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany; Institute of Ecology, Diversity and Evolution, Goethe University Frankfurt/Main, 60438 Frankfurt am Main, Germany
| | - Andrey V Soromotin
- Research Institute of Ecology and Natural Resources Management, Tyumen State University, 6 Volodarskogo Street, Tyumen, Russia
| | - Andrey Yurtaev
- Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 6 Volodarskogo Street, Tyumen, Russia
| | - Norbert Hölzel
- Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany
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Řezáčová V, Řezáč M, Gryndlerová H, Wilson GWT, Michalová T. Arbuscular mycorrhizal fungi favor invasive Echinops sphaerocephalus when grown in competition with native Inula conyzae. Sci Rep 2020; 10:20287. [PMID: 33219310 PMCID: PMC7679399 DOI: 10.1038/s41598-020-77030-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 09/28/2020] [Indexed: 12/04/2022] Open
Abstract
In a globalized world, plant invasions are common challenges for native ecosystems. Although a considerable number of invasive plants form arbuscular mycorrhizae, interactions between arbuscular mycorrhizal (AM) fungi and invasive and native plants are not well understood. In this study, we conducted a greenhouse experiment examining how AM fungi affect interactions of co-occurring plant species in the family Asteracea, invasive Echinops sphaerocephalus and native forb of central Europe Inula conyzae. The effects of initial soil disturbance, including the effect of intact or disturbed arbuscular mycorrhizal networks (CMNs), were examined. AM fungi supported the success of invasive E. sphaerocephalus in competition with native I. conyzae, regardless of the initial disturbance of CMNs. The presence of invasive E. sphaerocephalus decreased mycorrhizal colonization in I. conyzae, with a concomitant loss in mycorrhizal benefits. Our results confirm AM fungi represent one important mechanism of plant invasion for E. sphaerocephalus in semi-natural European grasslands.
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Affiliation(s)
- Veronika Řezáčová
- Crop Research Institute, Drnovská 507, Prague 6, Czech Republic.
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, Prague 4, Czech Republic.
| | - Milan Řezáč
- Crop Research Institute, Drnovská 507, Prague 6, Czech Republic
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, Prague 4, Czech Republic
| | - Hana Gryndlerová
- Crop Research Institute, Drnovská 507, Prague 6, Czech Republic
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, Prague 4, Czech Republic
| | - Gail W T Wilson
- Department of Natural Resource Ecology and Management, Oklahoma State University, Stillwater, OK, USA
| | - Tereza Michalová
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, Prague 4, Czech Republic
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15
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Zhang S, Shao L, Sun Z, Huang Y, Liu N. An atmospheric pollutant (inorganic nitrogen) alters the response of evergreen broad-leaved tree species to extreme drought. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 187:109750. [PMID: 31655412 DOI: 10.1016/j.ecoenv.2019.109750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 09/30/2019] [Accepted: 10/01/2019] [Indexed: 06/10/2023]
Abstract
Drought and nitrogen (N) deposition are important components of global climate and environmental change. In this greenhouse study, we investigated the ecophysiological responses of the seedlings of three subtropical forest plant species (Schima superba, Castanopsis fissa, and Michelia macclurei) to short-term experimental drought stress, N addition, and their interaction. The results showed that drought stress reduced the activities of antioxidant enzymes [superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT)] and total antioxidant capacity (T-AOC), but increased the malondialdehyde (MDA), abscisic acid (ABA), and proline (PRO) contents in plants. The PRO content, T-AOC, and antioxidant enzyme activities were increased, and ABA and MDA contents were decreased by N addition alone. Furthermore, N addition under drought stress increased antioxidant enzymes activities, PRO content, and T-AOC. The treatments, however, did not significantly affect the chlorophyll fluorescence parameters of the species. T-AOC was positively correlated with antioxidant enzyme activities in each species, indicating that antioxidant enzymes were important for plant resistance to oxidative stress. MDA content increased with the increase of ABA content, indicating that ABA may help regulate stomatal movement and drought-induced oxidative injury in plants. T-AOC was positively correlated with PRO content, probably because PRO participated in osmotic regulation of cells and increased osmotic stress resistance. These results indicate that N addition can reduce drought stress of subtropical forest plants and will help researchers predict how evergreen broad-leaved forests will respond to global change in the future.
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Affiliation(s)
- Shike Zhang
- CAS Engineering Laboratory for Ecological Restoration of Islands and Coastal Zones, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ling Shao
- School of Food Pharmaceutical Engineering, Zhao Qing University, Zhaoqing, 526061, China
| | - Zhongyu Sun
- Guangdong Open Laboratory of Geospatial Information Technology and Application, Guangzhou Institute of Geography, Guangzhou, 510070, China
| | - Yao Huang
- CAS Engineering Laboratory for Ecological Restoration of Islands and Coastal Zones, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Nan Liu
- CAS Engineering Laboratory for Ecological Restoration of Islands and Coastal Zones, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China.
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16
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Canini F, Zucconi L, Pacelli C, Selbmann L, Onofri S, Geml J. Vegetation, pH and Water Content as Main Factors for Shaping Fungal Richness, Community Composition and Functional Guilds Distribution in Soils of Western Greenland. Front Microbiol 2019; 10:2348. [PMID: 31681213 PMCID: PMC6797927 DOI: 10.3389/fmicb.2019.02348] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 09/26/2019] [Indexed: 01/29/2023] Open
Abstract
Fungi are the most abundant and one of the most diverse components of arctic soil ecosystems, where they are fundamental drivers of plant nutrient acquisition and recycling. Nevertheless, few studies have focused on the factors driving the diversity and functionality of fungal communities associated with these ecosystems, especially in the scope of global warming that is particularly affecting Greenland and is leading to shrub expansion, with expected profound changes of soil microbial communities. We used soil DNA metabarcoding to compare taxonomic and functional composition of fungal communities in three habitats [bare ground (BG), biological soil crusts (BSC), and vascular vegetation (VV) coverage] in Western Greenland. Fungal richness increased with the increasing complexity of the coverage, but BGs and BSCs samples showed the highest number of unique OTUs. Differences in both fungal community composition and distribution of functional guilds identified were correlated with edaphic factors (mainly pH and water content), in turn connected with the different type of coverage. These results suggest also possible losses of diversity connected to the expansion of VV and possible interactions among the members of different functional guilds, likely due to the nutrient limitation, with potential effects on elements recycling.
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Affiliation(s)
- Fabiana Canini
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
- Biodiversity Dynamics, Naturalis Biodiversity Center, Leiden, Netherlands
| | - Laura Zucconi
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Claudia Pacelli
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Laura Selbmann
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
- Section of Mycology, Italian National Antarctic Museum (MNA), Genoa, Italy
| | - Silvano Onofri
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - József Geml
- Biodiversity Dynamics, Naturalis Biodiversity Center, Leiden, Netherlands
- Faculty of Science, Leiden University, Leiden, Netherlands
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17
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Zhou Y, Deng J, Tai Z, Jiang L, Han J, Meng G, Li MH. Leaf Anatomy, Morphology and Photosynthesis of Three Tundra Shrubs after 7-Year Experimental Warming on Changbai Mountain. PLANTS 2019; 8:plants8080271. [PMID: 31394735 PMCID: PMC6724111 DOI: 10.3390/plants8080271] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 08/01/2019] [Accepted: 08/02/2019] [Indexed: 11/30/2022]
Abstract
Tundra is one of the most sensitive biomes to climate warming. Understanding plant eco-physiological responses to warming is critical because these traits can give feedback on the effects of climate-warming on tundra ecosystem. We used open-top chambers following the criteria of the International Tundra Experiment to passively warm air and soil temperatures year round in alpine tundra. Leaf size, photosynthesis and anatomy of three dominant species were investigated during the growing seasons after 7 years of continuous warming. Warming increased the maximal light-saturated photosynthetic rate (Pmax) by 43.6% for Dryas. octopetala var. asiatica and by 26.7% for Rhododendron confertissimum across the whole growing season, while warming did not significantly affect the Pmax of V. uliginosum. The leaf size of Dr. octopetala var. asiatica and Rh. confertissimum was increased by warming. No marked effects of warming on anatomical traits of Dr. octopetala var. asiatica were observed. Warming decreased the leaf thickness of Rh. confertissimum and Vaccinium uliginosum. This study highlights the species-specific responses to climate warming. Our results imply that Dr. octopetala var. asiatica could be more dominant because it, mainly in terms of leaf photosynthetic capacity and size, seems to have advantages over the other two species in a warming world.
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Affiliation(s)
- Yumei Zhou
- Ecological Technique and Engineering School, Shanghai Institute of Technology, Shanghai 201418, China
| | - Jifeng Deng
- Ecological Technique and Engineering School, Shanghai Institute of Technology, Shanghai 201418, China
| | - Zhijuan Tai
- Department of Tourism Economy, Changbai Mountain Academy of Sciences, Baihe 133633, China
| | - Lifen Jiang
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Jianqiu Han
- Ecological Technique and Engineering School, Shanghai Institute of Technology, Shanghai 201418, China
| | - Gelei Meng
- Ecological Technique and Engineering School, Shanghai Institute of Technology, Shanghai 201418, China
| | - Mai-He Li
- Swiss Federal Research Institute WSL, Zuercherstrasse 111, 8903 Birmensdorf, Switzerland.
- School of Geographical Sciences, Northeast Normal University, Changchun 130024, China.
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18
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Yang T, Tedersoo L, Soltis PS, Soltis DE, Gilbert JA, Sun M, Shi Y, Wang H, Li Y, Zhang J, Chen Z, Lin H, Zhao Y, Fu C, Chu H. Phylogenetic imprint of woody plants on the soil mycobiome in natural mountain forests of eastern China. THE ISME JOURNAL 2019; 13:686-697. [PMID: 30353037 PMCID: PMC6461945 DOI: 10.1038/s41396-018-0303-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 08/26/2018] [Accepted: 09/30/2018] [Indexed: 12/19/2022]
Abstract
Recent studies have detected strong phylogenetic signals in tree-fungus associations for diseased leaves and mycorrhizal symbioses. However, the extent of plant phylogenetic constraints on the free-living soil mycobiome remains unknown, especially at broad geographic scales. Here, 343 soil samples were collected adjacent to individual tree trunks, representing 58 woody plant species located in five mountain forests of eastern China. Integrating plant species identity and phylogenetic information, we aimed to unravel the relative contributions of phylogenetic relationships among tree species, abiotic environmental filtering, and geographic isolation to the geographic distribution of soil mycobiome. We found that the community dissimilarities of total fungi and each dominant guild (viz. saprotrophs, plant pathogens, and ectomycorrhizal fungi) significantly increased with increasing plant phylogenetic distance. Plant phylogenetic eigenvectors explained 11.4% of the variation in community composition, whereas environmental and spatial factors explained 24.1% and 7.2% of the variation, respectively. The communities of ectomycorrhizal fungi and plant pathogens were relatively more strongly affected by plant phylogeny than those of saprotrophs (13.7% and 10.4% vs. 8.5%). Overall, our results demonstrate how plant phylogeny, environment, and geographic space contribute to forest soil fungal distributions and suggest that the influence of plant phylogeny on fungal association may differ by guilds.
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Affiliation(s)
- Teng Yang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing, 210008, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Leho Tedersoo
- Natural History Museum, University of Tartu, 14a Ravila, Tartu, 50411, Estonia
| | - Pamela S Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, FL, 32611, USA
| | - Douglas E Soltis
- Florida Museum of Natural History, University of Florida, Gainesville, FL, 32611, USA
| | - Jack A Gilbert
- Department of Ecology and Evolution, and Department of Surgery, University of Chicago, Chicago, IL, 60637, USA
| | - Miao Sun
- Florida Museum of Natural History, University of Florida, Gainesville, FL, 32611, USA
| | - Yu Shi
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing, 210008, China
| | - Hongfei Wang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing, 210008, China
| | - Yuntao Li
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing, 210008, China
| | - Jian Zhang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Zhiduan Chen
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Hanyang Lin
- Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Yunpeng Zhao
- Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Chengxin Fu
- Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Haiyan Chu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing, 210008, China.
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19
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Zhao Q, Sundqvist MK, Newman GS, Classen AT. Soils beneath different arctic shrubs have contrasting responses to a natural gradient in temperature. Ecosphere 2018. [DOI: 10.1002/ecs2.2290] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Qiong Zhao
- CAS Key Laboratory of Forest Ecology and Management Institute of Applied Ecology Shenyang 110016 China
- The Center for Macroecology, Evolution and Climate The Natural History Museum of Denmark University of Copenhagen Universitetsparken 15, 2100 Copenhagen Ø Denmark
| | - Maja K. Sundqvist
- The Center for Macroecology, Evolution and Climate The Natural History Museum of Denmark University of Copenhagen Universitetsparken 15, 2100 Copenhagen Ø Denmark
- Department of Ecology and Environmental Science Umeå University 901 87 Umeå Sweden
| | - Gregory S. Newman
- The Center for Macroecology, Evolution and Climate The Natural History Museum of Denmark University of Copenhagen Universitetsparken 15, 2100 Copenhagen Ø Denmark
- Rubenstein School of Environment and Natural Resources University of Vermont Burlington Vermont 05405 USA
| | - Aimée T. Classen
- The Center for Macroecology, Evolution and Climate The Natural History Museum of Denmark University of Copenhagen Universitetsparken 15, 2100 Copenhagen Ø Denmark
- Rubenstein School of Environment and Natural Resources University of Vermont Burlington Vermont 05405 USA
- The Gund Institute for Environment University of Vermont Burlington Vermont 05405 USA
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20
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Dahl MB, Priemé A, Brejnrod A, Brusvang P, Lund M, Nymand J, Kramshøj M, Ro-Poulsen H, Haugwitz MS. Warming, shading and a moth outbreak reduce tundra carbon sink strength dramatically by changing plant cover and soil microbial activity. Sci Rep 2017; 7:16035. [PMID: 29167456 PMCID: PMC5700064 DOI: 10.1038/s41598-017-16007-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 11/01/2017] [Indexed: 01/09/2023] Open
Abstract
Future increases in temperature and cloud cover will alter plant growth and decomposition of the large carbon pools stored in Arctic soils. A better understanding of interactions between above- and belowground processes and communities of plants and microorganisms is essential for predicting Arctic ecosystem responses to climate change. We measured ecosystem CO2 fluxes during the growing season for seven years in a dwarf-shrub tundra in West Greenland manipulated with warming and shading and experiencing a natural larvae outbreak. Vegetation composition, soil fungal community composition, microbial activity, and nutrient availability were analyzed after six years of treatment. Warming and shading altered the plant community, reduced plant CO2 uptake, and changed fungal community composition. Ecosystem carbon accumulation decreased during the growing season by 61% in shaded plots and 51% in warmed plots. Also, plant recovery was reduced in both manipulations following the larvae outbreak during the fifth treatment year. The reduced plant recovery in manipulated plots following the larvae outbreak suggests that climate change may increase tundra ecosystem sensitivity to disturbances. Also, plant community changes mediated via reduced light and reduced water availability due to increased temperature can strongly lower the carbon sink strength of tundra ecosystems.
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Affiliation(s)
- Mathilde Borg Dahl
- Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK-1350, Copenhagen K, Denmark
- Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100, Copenhagen Ø, Denmark
| | - Anders Priemé
- Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK-1350, Copenhagen K, Denmark.
- Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100, Copenhagen Ø, Denmark.
| | - Asker Brejnrod
- Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100, Copenhagen Ø, Denmark
| | - Peter Brusvang
- Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK-1350, Copenhagen K, Denmark
- Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100, Copenhagen Ø, Denmark
| | - Magnus Lund
- Arctic Research Centre, Department of Bioscience, Aarhus University, Frederiksborgvej 399, DK-4000, Roskilde, Denmark
| | - Josephine Nymand
- Department of Environment and Mineral Resources, Greenland Institute of Natural Resources, Box 570, DK-3900, Nuuk, Greenland
| | - Magnus Kramshøj
- Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK-1350, Copenhagen K, Denmark
- Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100, Copenhagen Ø, Denmark
| | - Helge Ro-Poulsen
- Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK-1350, Copenhagen K, Denmark
- Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100, Copenhagen Ø, Denmark
| | - Merian Skouw Haugwitz
- Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK-1350, Copenhagen K, Denmark
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21
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Sørensen MV, Strimbeck R, Nystuen KO, Kapas RE, Enquist BJ, Graae BJ. Draining the Pool? Carbon Storage and Fluxes in Three Alpine Plant Communities. Ecosystems 2017. [DOI: 10.1007/s10021-017-0158-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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22
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Pickles BJ, Wilhelm R, Asay AK, Hahn AS, Simard SW, Mohn WW. Transfer of 13 C between paired Douglas-fir seedlings reveals plant kinship effects and uptake of exudates by ectomycorrhizas. THE NEW PHYTOLOGIST 2017; 214:400-411. [PMID: 27870059 DOI: 10.1111/nph.14325] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 10/08/2016] [Indexed: 05/27/2023]
Abstract
Processes governing the fixation, partitioning, and mineralization of carbon in soils are under increasing scrutiny as we develop a more comprehensive understanding of global carbon cycling. Here we examined fixation by Douglas-fir seedlings and transfer to associated ectomycorrhizal fungi, soil microbes, and full-sibling or nonsibling neighbouring seedlings. Stable isotope probing with 99% 13 C-CO2 was applied to trace 13 C-labelled photosynthate throughout plants, fungi, and soil microbes in an experiment designed to assess the effect of relatedness on 13 C transfer between plant pairs. The fixation and transfer of the 13 C label to plant, fungal, and soil microbial tissue was examined in biomass and phospholipid fatty acids. After a 6 d chase period, c. 26.8% of the 13 C remaining in the system was translocated below ground. Enrichment was proportionally greatest in ectomycorrhizal biomass. The presence of mesh barriers (0.5 or 35 μm) between seedlings did not restrict 13 C transfer. Fungi were the primary recipients of 13 C-labelled photosynthate throughout the system, representing 60-70% of total 13 C-enriched phospholipids. Full-sibling pairs exhibited significantly greater 13 C transfer to recipient roots in two of four Douglas-fir families, representing three- and fourfold increases (+ c. 4 μg excess 13 C) compared with nonsibling pairs. The existence of a root/mycorrhizal exudation-hyphal uptake pathway was supported.
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Affiliation(s)
- Brian J Pickles
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
- School of Biological Sciences, University of Reading, Harborne Building, Whiteknights, Reading, RG6 6AS, UK
| | - Roland Wilhelm
- Department of Microbiology & Immunology, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada, V6T 1Z3
| | - Amanda K Asay
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Aria S Hahn
- Department of Microbiology & Immunology, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada, V6T 1Z3
| | - Suzanne W Simard
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - William W Mohn
- Department of Microbiology & Immunology, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada, V6T 1Z3
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23
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Diversity of fungal assemblages in roots of Ericaceae in two Mediterranean contrasting ecosystems. C R Biol 2017; 340:226-237. [PMID: 28302364 DOI: 10.1016/j.crvi.2017.02.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 02/13/2017] [Accepted: 02/14/2017] [Indexed: 11/20/2022]
Abstract
The plants belonging to the Ericaceae family are morphologically diverse and widely distributed groups of plants. They are typically found in soil with naturally poor nutrient status. The objective of the current study was to identify cultivable mycobionts from roots of nine species of Ericaceae (Calluna vulgaris, Erica arborea, Erica australis, Erica umbellate, Erica scoparia, Erica multiflora, Arbutus unedo, Vaccinium myrtillus, and Vaccinium corymbosum). The sequencing approach was used to amplify the Internal Transcribed Spacer (ITS) region. Results from the phylogenetic analysis of ITS sequences stored in the Genbank confirmed that most of strains (78) were ascomycetes, 16 of these were closely related to Phialocephala spp, 12 were closely related to Helotiales spp and 6 belonged to various unidentified ericoid mycorrhizal fungal endophytes. Although the isolation frequencies differ sharply according to regions and ericaceous species, Helotiales was the most frequently encountered order from the diverse assemblage of associated fungi (46.15%), especially associated with C. vulgaris (19.23%) and V. myrtillus (6.41%), mostly present in the Loge (L) and Mellousa region (M). Moreover, multiple correspondence analysis (MCA) showed three distinct groups connecting fungal order to ericaceous species in different regions.
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24
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Yang T, Sun H, Shen C, Chu H. Fungal Assemblages in Different Habitats in an Erman's Birch Forest. Front Microbiol 2016; 7:1368. [PMID: 27625646 PMCID: PMC5003828 DOI: 10.3389/fmicb.2016.01368] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 08/18/2016] [Indexed: 12/12/2022] Open
Abstract
Recent meta-analyses of fungal diversity using deeply sequenced marker genes suggest that most fungal taxa are locally distributed. However, little is known about the extent of overlap and niche partitions in total fungal communities or functional guilds within distinct habitats on a local forest scale. Here, we compared fungal communities in endosphere (leaf interior), phyllosphere (leaf interior and associated surface area) and soil samples from an Erman's birch forest in Changbai Mountain, China. Community structures were significantly differentiated in terms of habitat, with soil having the highest fungal richness and phylogenetic diversity. Endophytic and phyllosphere fungi of Betula ermanii were more phylogenetically clustered compared with the corresponding soil fungi, indicating the ability of that host plants to filter and select their fungal partners. Furthermore, the majority of soil fungal taxa were soil specialists, while the dominant endosphere and phyllosphere taxa were aboveground generalists, with soil and plant foliage only sharing <8.2% fungal taxa. Most of the fungal taxa could be assigned to different functional guilds; however, the assigned guilds showed significant habitat specificity with variation in relative abundance. Collectively, the fungal assemblages in this Erman's birch forest were strictly niche specialized and constrained by weak migration among habitats. The findings suggest that phylogenetic relatedness and functional guilds' assignment can effectively interpret the certain ecological processes.
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Affiliation(s)
- Teng Yang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of SciencesNanjing, China
- University of Chinese Academy of SciencesBeijing, China
| | - Huaibo Sun
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of SciencesNanjing, China
| | - Congcong Shen
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of SciencesBeijing, China
| | - Haiyan Chu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of SciencesNanjing, China
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25
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Blanc-Betes E, Welker JM, Sturchio NC, Chanton JP, Gonzalez-Meler MA. Winter precipitation and snow accumulation drive the methane sink or source strength of Arctic tussock tundra. GLOBAL CHANGE BIOLOGY 2016; 22:2818-2833. [PMID: 26851545 DOI: 10.1111/gcb.13242] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 12/24/2015] [Indexed: 06/05/2023]
Abstract
Arctic winter precipitation is projected to increase with global warming, but some areas will experience decreases in snow accumulation. Although Arctic CH4 emissions may represent a significant climate forcing feedback, long-term impacts of changes in snow accumulation on CH4 fluxes remain uncertain. We measured ecosystem CH4 fluxes and soil CH4 and CO2 concentrations and (13) C composition to investigate the metabolic pathways and transport mechanisms driving moist acidic tundra CH4 flux over the growing season (Jun-Aug) after 18 years of experimental snow depth increases and decreases. Deeper snow increased soil wetness and warming, reducing soil %O2 levels and increasing thaw depth. Soil moisture, through changes in soil %O2 saturation, determined predominance of methanotrophy or methanogenesis, with soil temperature regulating the ecosystem CH4 sink or source strength. Reduced snow (RS) increased the fraction of oxidized CH4 (Fox) by 75-120% compared to Ambient, switching the system from a small source to a net CH4 sink (21 ± 2 and -31 ± 1 mg CH4 m(-2) season(-1) at Ambient and RS). Deeper snow reduced Fox by 35-40% and 90-100% in medium- (MS) and high- (HS) snow additions relative to Ambient, contributing to increasing the CH4 source strength of moist acidic tundra (464 ± 15 and 3561 ± 97 mg CH4 m(-2) season(-1) at MS and HS). Decreases in Fox with deeper snow were partly due to increases in plant-mediated CH4 transport associated with the expansion of tall graminoids. Deeper snow enhanced CH4 production within newly thawed soils, responding mainly to soil warming rather than to increases in acetate fermentation expected from thaw-induced increases in SOC availability. Our results suggest that increased winter precipitation will increase the CH4 source strength of Arctic tundra, but the resulting positive feedback on climate change will depend on the balance between areas with more or less snow accumulation than they are currently facing.
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Affiliation(s)
- Elena Blanc-Betes
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, 60607, USA
| | - Jeffrey M Welker
- Department of Biological Sciences, University of Alaska, Anchorage, Anchorage, AK, 99501, USA
| | - Neil C Sturchio
- Department of Geological Sciences, University of Delaware, Newark, DE, 19716, USA
| | - Jeffrey P Chanton
- Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, FL, 32306, USA
| | - Miquel A Gonzalez-Meler
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, 60607, USA
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26
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Mundra S, Halvorsen R, Kauserud H, Bahram M, Tedersoo L, Elberling B, Cooper EJ, Eidesen PB. Ectomycorrhizal and saprotrophic fungi respond differently to long-term experimentally increased snow depth in the High Arctic. Microbiologyopen 2016; 5:856-869. [PMID: 27255701 PMCID: PMC5061721 DOI: 10.1002/mbo3.375] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 04/11/2016] [Accepted: 04/18/2016] [Indexed: 11/24/2022] Open
Abstract
Changing climate is expected to alter precipitation patterns in the Arctic, with consequences for subsurface temperature and moisture conditions, community structure, and nutrient mobilization through microbial belowground processes. Here, we address the effect of increased snow depth on the variation in species richness and community structure of ectomycorrhizal (ECM) and saprotrophic fungi. Soil samples were collected weekly from mid‐July to mid‐September in both control and deep snow plots. Richness of ECM fungi was lower, while saprotrophic fungi was higher in increased snow depth plots relative to controls. [Correction added on 23 September 2016 after first online publication: In the preceding sentence, the richness of ECM and saprotrophic fungi were wrongly interchanged and have been fixed in this current version.] ECM fungal richness was related to soil NO3‐N, NH4‐N, and K; and saprotrophic fungi to NO3‐N and pH. Small but significant changes in the composition of saprotrophic fungi could be attributed to snow treatment and sampling time, but not so for the ECM fungi. Delayed snow melt did not influence the temporal variation in fungal communities between the treatments. Results suggest that some fungal species are favored, while others are disfavored resulting in their local extinction due to long‐term changes in snow amount. Shifts in species composition of fungal functional groups are likely to affect nutrient cycling, ecosystem respiration, and stored permafrost carbon.
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Affiliation(s)
- Sunil Mundra
- The University Centre in Svalbard, P.O. Box 156, NO-9171, Longyearbyen, Norway. , .,Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, P.O. Box 1066, Blindern, NO-0316, Oslo, Norway. ,
| | - Rune Halvorsen
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Håvard Kauserud
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, P.O. Box 1066, Blindern, NO-0316, Oslo, Norway
| | - Mohammad Bahram
- Institute of Ecology and Earth Sciences, Tartu University, 14A Ravila, 50411, Tartu, Estonia.,Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, SE 75236, Uppsala, Sweden
| | - Leho Tedersoo
- Natural History Museum, University of Tartu, 14A Ravila, 50411, Tartu, Estonia
| | - Bo Elberling
- Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, DK-1350, Copenhagen, Denmark
| | - Elisabeth J Cooper
- Department of Arctic and Marine Biology, Institute of Biosciences Fisheries and Economics, UiT The Arctic University of Norway, N-9037, Tromsø, Norway
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27
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Wild B, Gentsch N, Čapek P, Diáková K, Alves RJE, Bárta J, Gittel A, Hugelius G, Knoltsch A, Kuhry P, Lashchinskiy N, Mikutta R, Palmtag J, Schleper C, Schnecker J, Shibistova O, Takriti M, Torsvik VL, Urich T, Watzka M, Šantrůčková H, Guggenberger G, Richter A. Plant-derived compounds stimulate the decomposition of organic matter in arctic permafrost soils. Sci Rep 2016; 6:25607. [PMID: 27157964 PMCID: PMC4860603 DOI: 10.1038/srep25607] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 04/18/2016] [Indexed: 11/30/2022] Open
Abstract
Arctic ecosystems are warming rapidly, which is expected to promote soil organic matter (SOM) decomposition. In addition to the direct warming effect, decomposition can also be indirectly stimulated via increased plant productivity and plant-soil C allocation, and this so called “priming effect” might significantly alter the ecosystem C balance. In this study, we provide first mechanistic insights into the susceptibility of SOM decomposition in arctic permafrost soils to priming. By comparing 119 soils from four locations across the Siberian Arctic that cover all horizons of active layer and upper permafrost, we found that an increased availability of plant-derived organic C particularly stimulated decomposition in subsoil horizons where most of the arctic soil carbon is located. Considering the 1,035 Pg of arctic soil carbon, such an additional stimulation of decomposition beyond the direct temperature effect can accelerate net ecosystem C losses, and amplify the positive feedback to global warming.
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Affiliation(s)
- Birgit Wild
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria.,Austrian Polar Research Institute, Vienna, Austria.,Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Norman Gentsch
- Institute of Soil Science, Leibniz Universität Hannover, Hannover, Germany
| | - Petr Čapek
- Department of Ecosystem Biology, University of South Bohemia, České Budějovice, Czech Republic
| | - Kateřina Diáková
- Department of Ecosystem Biology, University of South Bohemia, České Budějovice, Czech Republic
| | - Ricardo J Eloy Alves
- Austrian Polar Research Institute, Vienna, Austria.,Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria
| | - Jiři Bárta
- Department of Ecosystem Biology, University of South Bohemia, České Budějovice, Czech Republic
| | - Antje Gittel
- Department of Biology, Centre for Geobiology, University of Bergen, Bergen, Norway.,Department of Bioscience, Center for Geomicrobiology, Aarhus, Denmark
| | - Gustaf Hugelius
- Department of Physical Geography, Stockholm University, Stockholm, Sweden
| | - Anna Knoltsch
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria.,Austrian Polar Research Institute, Vienna, Austria
| | - Peter Kuhry
- Department of Physical Geography, Stockholm University, Stockholm, Sweden
| | - Nikolay Lashchinskiy
- Central Siberian Botanical Garden, Siberian Branch of Russian Academy of Sciences, Novosibirsk, Russia
| | - Robert Mikutta
- Institute of Soil Science, Leibniz Universität Hannover, Hannover, Germany.,Soil Science and Soil Protection, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Juri Palmtag
- Department of Physical Geography, Stockholm University, Stockholm, Sweden
| | - Christa Schleper
- Austrian Polar Research Institute, Vienna, Austria.,Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria
| | - Jörg Schnecker
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria.,Austrian Polar Research Institute, Vienna, Austria.,Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH, USA
| | - Olga Shibistova
- Institute of Soil Science, Leibniz Universität Hannover, Hannover, Germany.,VN Sukachev Institute of Forest, Siberian Branch of Russian Academy of Sciences, Krasnoyarsk, Russia
| | - Mounir Takriti
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria.,Austrian Polar Research Institute, Vienna, Austria.,Lancaster Environment Centre, Lancaster University, Lancaster, UK
| | - Vigdis L Torsvik
- Department of Biology, Centre for Geobiology, University of Bergen, Bergen, Norway
| | - Tim Urich
- Austrian Polar Research Institute, Vienna, Austria.,Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria.,Institute of Microbiology, Ernst-Moritz-Arndt University, Greifswald, Germany
| | - Margarete Watzka
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
| | - Hana Šantrůčková
- Department of Ecosystem Biology, University of South Bohemia, České Budějovice, Czech Republic
| | - Georg Guggenberger
- Institute of Soil Science, Leibniz Universität Hannover, Hannover, Germany.,VN Sukachev Institute of Forest, Siberian Branch of Russian Academy of Sciences, Krasnoyarsk, Russia
| | - Andreas Richter
- Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria.,Austrian Polar Research Institute, Vienna, Austria
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28
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Deslippe JR, Hartmann M, Grayston SJ, Simard SW, Mohn WW. Stable isotope probing implicates a species of Cortinarius in carbon transfer through ectomycorrhizal fungal mycelial networks in Arctic tundra. THE NEW PHYTOLOGIST 2016; 210:383-90. [PMID: 26681156 DOI: 10.1111/nph.13797] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Affiliation(s)
- Julie R Deslippe
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Martin Hartmann
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Zuercherstrasse 111, CH-8903, Birmensdorf, Switzerland
- Molecular Ecology, Institute for Sustainability Sciences, Agroscope, Reckenholzstrasse 191, CH-8046, Zurich, Switzerland
- Department of Microbiology and Immunology, Life Sciences Institute, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Susan J Grayston
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Suzanne W Simard
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada
| | - William W Mohn
- Department of Microbiology and Immunology, Life Sciences Institute, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
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29
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Hewitt RE, Bent E, Hollingsworth TN, Chapin FS, Taylor DL. Resilience of Arctic mycorrhizal fungal communities after wildfire facilitated by resprouting shrubs. ECOSCIENCE 2015. [DOI: 10.2980/20-3-3620] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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30
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Classen AT, Sundqvist MK, Henning JA, Newman GS, Moore JAM, Cregger MA, Moorhead LC, Patterson CM. Direct and indirect effects of climate change on soil microbial and soil microbial-plant interactions: What lies ahead? Ecosphere 2015. [DOI: 10.1890/es15-00217.1] [Citation(s) in RCA: 337] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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31
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Hollesen J, Buchwal A, Rachlewicz G, Hansen BU, Hansen MO, Stecher O, Elberling B. Winter warming as an important co-driver for Betula nana growth in western Greenland during the past century. GLOBAL CHANGE BIOLOGY 2015; 21:2410-23. [PMID: 25788025 PMCID: PMC4657495 DOI: 10.1111/gcb.12913] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 02/05/2015] [Accepted: 02/14/2015] [Indexed: 05/09/2023]
Abstract
Growing season conditions are widely recognized as the main driver for tundra shrub radial growth, but the effects of winter warming and snow remain an open question. Here, we present a more than 100 years long Betula nana ring-width chronology from Disko Island in western Greenland that demonstrates a highly significant and positive growth response to both summer and winter air temperatures during the past century. The importance of winter temperatures for Betula nana growth is especially pronounced during the periods from 1910-1930 to 1990-2011 that were dominated by significant winter warming. To explain the strong winter importance on growth, we assessed the importance of different environmental factors using site-specific measurements from 1991 to 2011 of soil temperatures, sea ice coverage, precipitation and snow depths. The results show a strong positive growth response to the amount of thawing and growing degree-days as well as to winter and spring soil temperatures. In addition to these direct effects, a strong negative growth response to sea ice extent was identified, indicating a possible link between local sea ice conditions, local climate variations and Betula nana growth rates. Data also reveal a clear shift within the last 20 years from a period with thick snow depths (1991-1996) and a positive effect on Betula nana radial growth, to a period (1997-2011) with generally very shallow snow depths and no significant growth response towards snow. During this period, winter and spring soil temperatures have increased significantly suggesting that the most recent increase in Betula nana radial growth is primarily triggered by warmer winter and spring air temperatures causing earlier snowmelt that allows the soils to drain and warm quicker. The presented results may help to explain the recently observed 'greening of the Arctic' which may further accelerate in future years due to both direct and indirect effects of winter warming.
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Affiliation(s)
- Jørgen Hollesen
- Center for Permafrost (CENPERM), Department of Geoscience and Natural Resource Management, University of CopenhagenØster Voldgade 10, DK-1350, Copenhagen, Denmark
- Department of Conservation and Natural Sciences, National Museum of Denmark, I.C. ModewegsvejBrede, DK-2800, Lyngby, Denmark
| | - Agata Buchwal
- Institute of Geoecology and Geoinformation, Adam Mickiewicz UniversityDziegielowa 27, 61-680, Poznan, Poland
- Department of Biological Sciences, University of Alaska Anchorage, Ecosystem and Biomedical Lab3151 Alumni Loop, Anchorage, AK 99508, USA
| | - Grzegorz Rachlewicz
- Institute of Geoecology and Geoinformation, Adam Mickiewicz UniversityDziegielowa 27, 61-680, Poznan, Poland
| | - Birger U Hansen
- Center for Permafrost (CENPERM), Department of Geoscience and Natural Resource Management, University of CopenhagenØster Voldgade 10, DK-1350, Copenhagen, Denmark
| | - Marc O Hansen
- Center for Permafrost (CENPERM), Department of Geoscience and Natural Resource Management, University of CopenhagenØster Voldgade 10, DK-1350, Copenhagen, Denmark
| | - Ole Stecher
- Arctic Station, University of CopenhagenQeqertarsuaq, Greenland
| | - Bo Elberling
- Center for Permafrost (CENPERM), Department of Geoscience and Natural Resource Management, University of CopenhagenØster Voldgade 10, DK-1350, Copenhagen, Denmark
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32
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Gorzelak MA, Asay AK, Pickles BJ, Simard SW. Inter-plant communication through mycorrhizal networks mediates complex adaptive behaviour in plant communities. AOB PLANTS 2015; 7:plv050. [PMID: 25979966 PMCID: PMC4497361 DOI: 10.1093/aobpla/plv050] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 03/26/2015] [Indexed: 05/03/2023]
Abstract
Adaptive behaviour of plants, including rapid changes in physiology, gene regulation and defence response, can be altered when linked to neighbouring plants by a mycorrhizal network (MN). Mechanisms underlying the behavioural changes include mycorrhizal fungal colonization by the MN or interplant communication via transfer of nutrients, defence signals or allelochemicals. We focus this review on our new findings in ectomycorrhizal ecosystems, and also review recent advances in arbuscular mycorrhizal systems. We have found that the behavioural changes in ectomycorrhizal plants depend on environmental cues, the identity of the plant neighbour and the characteristics of the MN. The hierarchical integration of this phenomenon with other biological networks at broader scales in forest ecosystems, and the consequences we have observed when it is interrupted, indicate that underground 'tree talk' is a foundational process in the complex adaptive nature of forest ecosystems.
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Affiliation(s)
- Monika A Gorzelak
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Amanda K Asay
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Brian J Pickles
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
| | - Suzanne W Simard
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
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33
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Song YY, Simard SW, Carroll A, Mohn WW, Zeng RS. Defoliation of interior Douglas-fir elicits carbon transfer and stress signalling to ponderosa pine neighbors through ectomycorrhizal networks. Sci Rep 2015; 5:8495. [PMID: 25683155 PMCID: PMC4329569 DOI: 10.1038/srep08495] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 01/20/2015] [Indexed: 01/01/2023] Open
Abstract
Extensive regions of interior Douglas-fir (Pseudotsuga menziesii var. glauca, IDF) forests in North America are being damaged by drought and western spruce budworm (Choristoneura occidentalis). This damage is resulting from warmer and drier summers associated with climate change. To test whether defoliated IDF can directly transfer resources to ponderosa pine (Pinus ponderosae) regenerating nearby, thus aiding in forest recovery, we examined photosynthetic carbon transfer and defense enzyme response. We grew pairs of ectomycorrhizal IDF 'donor' and ponderosa pine 'receiver' seedlings in pots and isolated transfer pathways by comparing 35 μm, 0.5 μm and no mesh treatments; we then stressed IDF donors either through manual defoliation or infestation by the budworm. We found that manual defoliation of IDF donors led to transfer of photosynthetic carbon to neighboring receivers through mycorrhizal networks, but not through soil or root pathways. Both manual and insect defoliation of donors led to increased activity of peroxidase, polyphenol oxidase and superoxide dismutase in the ponderosa pine receivers, via a mechanism primarily dependent on the mycorrhizal network. These findings indicate that IDF can transfer resources and stress signals to interspecific neighbors, suggesting ectomycorrhizal networks can serve as agents of interspecific communication facilitating recovery and succession of forests after disturbance.
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Affiliation(s)
- Yuan Yuan Song
- College of Life Sciences, Fujian Agriculture and Forestry University, Jinshan, Fuzhou 350002, P.R. China
| | - Suzanne W. Simard
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada
| | - Allan Carroll
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada
| | - William W. Mohn
- Department of Microbiology & Immunology, Life Sciences Institute, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Ren Sen Zeng
- College of Life Sciences, Fujian Agriculture and Forestry University, Jinshan, Fuzhou 350002, P.R. China
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34
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Qiao X, Bei S, Li C, Dong Y, Li H, Christie P, Zhang F, Zhang J. Enhancement of faba bean competitive ability by arbuscular mycorrhizal fungi is highly correlated with dynamic nutrient acquisition by competing wheat. Sci Rep 2015; 5:8122. [PMID: 25631933 PMCID: PMC4309967 DOI: 10.1038/srep08122] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 01/06/2015] [Indexed: 11/09/2022] Open
Abstract
The mechanistic understanding of the dynamic processes linking nutrient acquisition and biomass production of competing individuals can be instructive in optimizing intercropping systems. Here, we examine the effect of inoculation with Funneliformis mosseae on competitive dynamics between wheat and faba bean. Wheat is less responsive to mycorrhizal inoculation. Both inoculated and uninoculated wheat attained the maximum instantaneous N and P capture approximately five days before it attained the maximum instantaneous biomass production, indicating that wheat detected the competitor and responded physiologically to resource limitation prior to the biomass response. By contrast, the instantaneous N and P capture by uninoculated faba bean remained low throughout the growth period, and plant growth was not significantly affected by competing wheat. However, inoculation substantially enhanced biomass production and N and P acquisition of faba bean. The exudation of citrate and malate acids and acid phosphatase activity were greater in mycorrhizal than in uninoculated faba bean, and rhizosphere pH tended to decrease. We conclude that under N and P limiting conditions, temporal separation of N and P acquisition by competing plant species and enhancement of complementary resource use in the presence of AMF might be attributable to the competitive co-existence of faba bean and wheat.
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Affiliation(s)
- Xu Qiao
- Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University; Key Laboratory of Plant-Soil Interactions, Ministry of Education, Beijing 100193, China
- Institute of Grain Groups, Xinjiang Academy of Agricultural Sciences; Key Laboratory of Crop Ecophysiology and Farming Systems in Desert Oasis Region, Ministry of Agriculture, Urumqi, Xinjiang 830091, China
| | - Shuikuan Bei
- Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University; Key Laboratory of Plant-Soil Interactions, Ministry of Education, Beijing 100193, China
| | - Chunjie Li
- Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University; Key Laboratory of Plant-Soil Interactions, Ministry of Education, Beijing 100193, China
| | - Yan Dong
- College of Resources and Environment, Yunnan Agricultural University, Kunming 650201, China
| | - Haigang Li
- Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University; Key Laboratory of Plant-Soil Interactions, Ministry of Education, Beijing 100193, China
| | - Peter Christie
- Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University; Key Laboratory of Plant-Soil Interactions, Ministry of Education, Beijing 100193, China
| | - Fusuo Zhang
- Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University; Key Laboratory of Plant-Soil Interactions, Ministry of Education, Beijing 100193, China
| | - Junling Zhang
- Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University; Key Laboratory of Plant-Soil Interactions, Ministry of Education, Beijing 100193, China
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35
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Resource Transfer Between Plants Through Ectomycorrhizal Fungal Networks. ECOLOGICAL STUDIES 2015. [DOI: 10.1007/978-94-017-7395-9_5] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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36
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Iversen CM, Sloan VL, Sullivan PF, Euskirchen ES, McGuire AD, Norby RJ, Walker AP, Warren JM, Wullschleger SD. The unseen iceberg: plant roots in arctic tundra. THE NEW PHYTOLOGIST 2015; 205:34-58. [PMID: 25209220 DOI: 10.1111/nph.13003] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 07/10/2014] [Indexed: 06/03/2023]
Abstract
Plant roots play a critical role in ecosystem function in arctic tundra, but root dynamics in these ecosystems are poorly understood. To address this knowledge gap, we synthesized available literature on tundra roots, including their distribution, dynamics and contribution to ecosystem carbon and nutrient fluxes, and highlighted key aspects of their representation in terrestrial biosphere models. Across all tundra ecosystems, belowground plant biomass exceeded aboveground biomass, with the exception of polar desert tundra. Roots were shallowly distributed in the thin layer of soil that thaws annually, and were often found in surface organic soil horizons. Root traits - including distribution, chemistry, anatomy and resource partitioning - play an important role in controlling plant species competition, and therefore ecosystem carbon and nutrient fluxes, under changing climatic conditions, but have only been quantified for a small fraction of tundra plants. Further, the annual production and mortality of fine roots are key components of ecosystem processes in tundra, but extant data are sparse. Tundra root traits and dynamics should be the focus of future research efforts. Better representation of the dynamics and characteristics of tundra roots will improve the utility of models for the evaluation of the responses of tundra ecosystems to changing environmental conditions.
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Affiliation(s)
- Colleen M Iversen
- Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA; Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831-6301, USA
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37
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Heskel MA, Greaves HE, Turnbull MH, O'Sullivan OS, Shaver GR, Griffin KL, Atkin OK. Thermal acclimation of shoot respiration in an Arctic woody plant species subjected to 22 years of warming and altered nutrient supply. GLOBAL CHANGE BIOLOGY 2014; 20:2618-2630. [PMID: 24510889 DOI: 10.1111/gcb.12544] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 01/04/2014] [Indexed: 06/03/2023]
Abstract
Despite concern about the status of carbon (C) in the Arctic tundra, there is currently little information on how plant respiration varies in response to environmental change in this region. We quantified the impact of long-term nitrogen (N) and phosphorus (P) treatments and greenhouse warming on the short-term temperature (T) response and sensitivity of leaf respiration (R), the high-T threshold of R, and associated traits in shoots of the Arctic shrub Betula nana in experimental plots at Toolik Lake, Alaska. Respiration only acclimated to greenhouse warming in plots provided with both N and P (resulting in a ~30% reduction in carbon efflux in shoots measured at 10 and 20 °C), suggesting a nutrient dependence of metabolic adjustment. Neither greenhouse nor N+P treatments impacted on the respiratory sensitivity to T (Q10 ); overall, Q10 values decreased with increasing measuring T, from ~3.0 at 5 °C to ~1.5 at 35 °C. New high-resolution measurements of R across a range of measuring Ts (25-70 °C) yielded insights into the T at which maximal rates of R occurred (Tmax ). Although growth temperature did not affect Tmax , N+P fertilization increased Tmax values ~5 °C, from 53 to 58 °C. N+P fertilized shoots exhibited greater rates of R than nonfertilized shoots, with this effect diminishing under greenhouse warming. Collectively, our results highlight the nutrient dependence of thermal acclimation of leaf R in B. nana, suggesting that the metabolic efficiency allowed via thermal acclimation may be impaired at current levels of soil nutrient availability. This finding has important implications for predicting carbon fluxes in Arctic ecosystems, particularly if soil N and P become more abundant in the future as the tundra warms.
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Affiliation(s)
- Mary A Heskel
- Research School of Biology, Division of Plant Sciences, Building 46, Australian National University, Canberra, ACT 0200, Australia
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Mohan JE, Cowden CC, Baas P, Dawadi A, Frankson PT, Helmick K, Hughes E, Khan S, Lang A, Machmuller M, Taylor M, Witt CA. Mycorrhizal fungi mediation of terrestrial ecosystem responses to global change: mini-review. FUNGAL ECOL 2014. [DOI: 10.1016/j.funeco.2014.01.005] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Sistla SA, Rastetter EB, Schimel JP. Responses of a tundra system to warming using SCAMPS: a stoichiometrically coupled, acclimating microbe–plant–soil model. ECOL MONOGR 2014. [DOI: 10.1890/12-2119.1] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Blaalid R, Davey ML, Kauserud H, Carlsen T, Halvorsen R, Høiland K, Eidesen PB. Arctic root-associated fungal community composition reflects environmental filtering. Mol Ecol 2014; 23:649-59. [DOI: 10.1111/mec.12622] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 11/19/2013] [Accepted: 12/04/2013] [Indexed: 12/01/2022]
Affiliation(s)
- Rakel Blaalid
- Department of Biology; Microbial Evolution Research Group (MERG); University of Oslo; PO Box 1066 Blindern NO-0316 Oslo Norway
| | - Marie L. Davey
- The University Centre in Svalbard; PO Box 156 NO-9171 Longyearbyen Norway
| | - Håvard Kauserud
- Department of Biology; Microbial Evolution Research Group (MERG); University of Oslo; PO Box 1066 Blindern NO-0316 Oslo Norway
| | - Tor Carlsen
- Department of Biology; Microbial Evolution Research Group (MERG); University of Oslo; PO Box 1066 Blindern NO-0316 Oslo Norway
| | - Rune Halvorsen
- Natural History Museum; University of Oslo; PO Box 1172 Blindern NO-0318 Oslo Norway
| | - Klaus Høiland
- Department of Biology; Microbial Evolution Research Group (MERG); University of Oslo; PO Box 1066 Blindern NO-0316 Oslo Norway
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Microbial competition in polar soils: a review of an understudied but potentially important control on productivity. BIOLOGY 2013; 2:533-54. [PMID: 24832797 PMCID: PMC3960893 DOI: 10.3390/biology2020533] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 03/11/2013] [Accepted: 03/12/2013] [Indexed: 01/29/2023]
Abstract
Intermicrobial competition is known to occur in many natural environments, and can result from direct conflict between organisms, or from differential rates of growth, colonization, and/or nutrient acquisition. It has been difficult to extensively examine intermicrobial competition in situ, but these interactions may play an important role in the regulation of the many biogeochemical processes that are tied to microbial communities in polar soils. A greater understanding of how competition influences productivity will improve projections of gas and nutrient flux as the poles warm, may provide biotechnological opportunities for increasing the degradation of contaminants in polar soil, and will help to predict changes in communities of higher organisms, such as plants.
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Heskel M, Greaves H, Kornfeld A, Gough L, Atkin OK, Turnbull MH, Shaver G, Griffin KL. Differential physiological responses to environmental change promote woody shrub expansion. Ecol Evol 2013; 3:1149-62. [PMID: 23762503 PMCID: PMC3678471 DOI: 10.1002/ece3.525] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 02/13/2013] [Accepted: 02/14/2013] [Indexed: 12/02/2022] Open
Abstract
Direct and indirect effects of warming are increasingly modifying the carbon-rich vegetation and soils of the Arctic tundra, with important implications for the terrestrial carbon cycle. Understanding the biological and environmental influences on the processes that regulate foliar carbon cycling in tundra species is essential for predicting the future terrestrial carbon balance in this region. To determine the effect of climate change impacts on gas exchange in tundra, we quantified foliar photosynthesis (Anet), respiration in the dark and light (RD and RL, determined using the Kok method), photorespiration (PR), carbon gain efficiency (CGE, the ratio of photosynthetic CO2 uptake to total CO2 exchange of photosynthesis, PR, and respiration), and leaf traits of three dominant species – Betula nana, a woody shrub; Eriophorum vaginatum, a graminoid; and Rubus chamaemorus, a forb – grown under long-term warming and fertilization treatments since 1989 at Toolik Lake, Alaska. Under warming, B. nana exhibited the highest rates of Anet and strongest light inhibition of respiration, increasing CGE nearly 50% compared with leaves grown in ambient conditions, which corresponded to a 52% increase in relative abundance. Gas exchange did not shift under fertilization in B. nana despite increases in leaf N and P and near-complete dominance at the community scale, suggesting a morphological rather than physiological response. Rubus chamaemorus, exhibited minimal shifts in foliar gas exchange, and responded similarly to B. nana under treatment conditions. By contrast, E. vaginatum, did not significantly alter its gas exchange physiology under treatments and exhibited dramatic decreases in relative cover (warming: −19.7%; fertilization: −79.7%; warming with fertilization: −91.1%). Our findings suggest a foliar physiological advantage in the woody shrub B. nana that is further mediated by warming and increased soil nutrient availability, which may facilitate shrub expansion and in turn alter the terrestrial carbon cycle in future tundra environments.
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Affiliation(s)
- Mary Heskel
- Department of Ecology, Evolution, and Environmental Biology, Columbia University New York, New York USA, 10027
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Kornfeld A, Heskel M, Atkin OK, Gough L, Griffin KL, Horton TW, Turnbull MH. Respiratory flexibility and efficiency are affected by simulated global change in Arctic plants. THE NEW PHYTOLOGIST 2013; 197:1161-1172. [PMID: 23278298 DOI: 10.1111/nph.12083] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2012] [Accepted: 11/04/2012] [Indexed: 06/01/2023]
Abstract
Laboratory studies indicate that, in response to environmental conditions, plants modulate respiratory electron partitioning between the 'energy-wasteful' alternative pathway (AP) and the 'energy-conserving' cytochrome pathway (CP). Field data, however, are scarce. Here we investigate how 20-yr field manipulations simulating global change affected electron partitioning in Alaskan Arctic tundra species. We sampled leaves from three dominant tundra species - Betula nana, Eriophorum vaginatum and Rubus chamaemorus - that had been strongly affected by manipulations of soil nutrients, light availability, and warming. We measured foliar dark respiration, in-vivo electron partitioning and alternative oxidase/cytochrome c oxidase concentrations in addition to leaf traits and mitochondrial ultrastructure. Changes in leaf traits and ultrastructure were similar across species. Respiration at 20°C (R(20)) was reduced 15% in all three species grown at elevated temperature, suggesting thermal acclimation of respiration. In Betula, the species with the largest growth response to added nutrients, CP activity increased from 9.4 ± 0.8 to 16.6 ± 1.6 nmol O(2) g(-1) DM s(-1) whereas AP activity was unchanged. The ability of Betula to selectively increase CP activity in response to the environment may contribute to its overall ecological success by increasing respiratory energy efficiency, and thus retaining more carbon for growth.
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Affiliation(s)
- Ari Kornfeld
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand
| | - Mary Heskel
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, NY, 10027, USA
| | - Owen K Atkin
- Division of Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT, 0200, Australia
| | - Laura Gough
- Department of Biology, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Kevin L Griffin
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, NY, 10027, USA
- Department of Earth and Environmental Sciences, Columbia University, New York, NY, 10027, USA
- Lamont-Doherty Earth Observatory, Columbia University, 61 Rt 9W, Palisades, NY, 10964, USA
| | - Travis W Horton
- Department of Geological Sciences, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand
| | - Matthew H Turnbull
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand
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Sistla SA, Schimel JP. Stoichiometric flexibility as a regulator of carbon and nutrient cycling in terrestrial ecosystems under change. THE NEW PHYTOLOGIST 2012; 196:68-78. [PMID: 22924404 DOI: 10.1111/j.1469-8137.2012.04234.x] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Ecosystems across the biosphere are subject to rapid changes in elemental balance and climatic regimes. A major force structuring ecological responses to these perturbations lies in the stoichiometric flexibility of systems - the ability to adjust their elemental balance whilst maintaining function. The potential for stoichiometric flexibility underscores the utility of the application of a framework highlighting the constraints and consequences of elemental mass balance and energy cycling in biological systems to address global change phenomena. Improvement in the modeling of ecological responses to disturbance requires the consideration of the stoichiometric flexibility of systems within and across relevant scales. Although a multitude of global change studies over various spatial and temporal scales exist, the explicit consideration of the role played by stoichiometric flexibility in linking micro-scale to macro-scale biogeochemical processes in terrestrial ecosystems remains relatively unexplored. Focusing on terrestrial systems under change, we discuss the mechanisms by which stoichiometric flexibility might be expressed and connected from organisms to ecosystems. We suggest that the transition from the expression of stoichiometric flexibility within individuals to the community and ecosystem scales is a key mechanism regulating the extent to which environmental perturbation may alter ecosystem carbon and nutrient cycling dynamics.
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Affiliation(s)
- Seeta A Sistla
- Department of Ecology, Evolution and Marine Biology, University of California Santa Barbara, Santa Barbara, CA 93108, USA
| | - Joshua P Schimel
- Department of Ecology, Evolution and Marine Biology, University of California Santa Barbara, Santa Barbara, CA 93108, USA
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Timling I, Taylor DL. Peeking through a frosty window: molecular insights into the ecology of Arctic soil fungi. FUNGAL ECOL 2012. [DOI: 10.1016/j.funeco.2012.01.009] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Vohník M, Sadowsky JJ, Kohout P, Lhotáková Z, Nestby R, Kolařík M. Novel root-fungus symbiosis in Ericaceae: sheathed ericoid mycorrhiza formed by a hitherto undescribed basidiomycete with affinities to Trechisporales. PLoS One 2012; 7:e39524. [PMID: 22761814 PMCID: PMC3382583 DOI: 10.1371/journal.pone.0039524] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 05/22/2012] [Indexed: 11/19/2022] Open
Abstract
Ericaceae (the heath family) are widely distributed calcifuges inhabiting soils with inherently poor nutrient status. Ericaceae overcome nutrient limitation through symbiosis with ericoid mycorrhizal (ErM) fungi that mobilize nutrients complexed in recalcitrant organic matter. At present, recognized ErM fungi include a narrow taxonomic range within the Ascomycota, and the Sebacinales, basal Hymenomycetes with unclamped hyphae and imperforate parenthesomes. Here we describe a novel type of basidiomycetous ErM symbiosis, termed 'sheathed ericoid mycorrhiza', discovered in two habitats in mid-Norway as a co-dominant mycorrhizal symbiosis in Vaccinium spp. The basidiomycete forming sheathed ErM possesses clamped hyphae with perforate parenthesomes, produces 1- to 3-layer sheaths around terminal parts of hair roots and colonizes their rhizodermis intracellularly forming hyphal coils typical for ErM symbiosis. Two basidiomycetous isolates were obtained from sheathed ErM and molecular and phylogenetic tools were used to determine their identity; they were also examined for the ability to form sheathed ErM and lignocellulolytic potential. Surprisingly, ITS rDNA of both conspecific isolates failed to amplify with the most commonly used primer pairs, including ITS1 and ITS1F + ITS4. Phylogenetic analysis of nuclear LSU, SSU and 5.8S rDNA indicates that the basidiomycete occupies a long branch residing in the proximity of Trechisporales and Hymenochaetales, but lacks a clear sequence relationship (>90% similarity) to fungi currently placed in these orders. The basidiomycete formed the characteristic sheathed ErM symbiosis and enhanced growth of Vaccinium spp. in vitro, and degraded a recalcitrant aromatic substrate that was left unaltered by common ErM ascomycetes. Our findings provide coherent evidence that this hitherto undescribed basidiomycete forms a morphologically distinct ErM symbiosis that may occur at significant levels under natural conditions, yet remain undetected when subject to amplification by 'universal' primers. The lignocellulolytic assay suggests the basidiomycete may confer host adaptations distinct from those provisioned by the so far investigated ascomycetous ErM fungi.
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Affiliation(s)
- Martin Vohník
- Department of Mycorrhizal Symbioses, Institute of Botany, Academy of Sciences of the Czech Republic, Průhonice, Czech Republic.
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Deslippe JR, Hartmann M, Simard SW, Mohn WW. Long-term warming alters the composition of Arctic soil microbial communities. FEMS Microbiol Ecol 2012; 82:303-15. [DOI: 10.1111/j.1574-6941.2012.01350.x] [Citation(s) in RCA: 134] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2011] [Revised: 02/27/2012] [Accepted: 02/27/2012] [Indexed: 10/28/2022] Open
Affiliation(s)
| | | | - Suzanne W. Simard
- Department of Forest Science; Faculty of Forest Science, University of British Columbia; Vancouver; BC; Canada
| | - William W. Mohn
- Department of Microbiology and Immunology; Life Sciences Institute; University of British Columbia; Vancouver; BC; Canada
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Simard SW, Beiler KJ, Bingham MA, Deslippe JR, Philip LJ, Teste FP. Mycorrhizal networks: Mechanisms, ecology and modelling. FUNGAL BIOL REV 2012. [DOI: 10.1016/j.fbr.2012.01.001] [Citation(s) in RCA: 157] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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