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Tang X, Yang J, Lin D, Lin H, Xiao X, Chen S, Huang Y, Qian X. Community assembly of ectomycorrhizal fungal communities in pure and mixed Pinus massoniana forests. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 362:121312. [PMID: 38824888 DOI: 10.1016/j.jenvman.2024.121312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Revised: 05/18/2024] [Accepted: 05/30/2024] [Indexed: 06/04/2024]
Abstract
Ectomycorrhizal (EcM) fungi play an important role in nutrient cycling and community ecological dynamics and are widely acknowledged as important components of forest ecosystems. However, little information is available regarding EcM fungal community structure or the possible relationship between EcM fungi, soil properties, and forestry activities in Pinus massoniana forests. In this study, we evaluated soil properties, extracellular enzyme activities, and fungal diversity and community composition in root and soil samples from pure Pinus massoniana natural forests, pure P. massoniana plantations, and P. massoniana and Liquidambar gracilipes mixed forests. The mixed forest showed the highest EcM fungal diversity in both root and bulk soil samples. Community composition and co-occurrence network structures differed significantly between forest types. Variation in the EcM fungal community was significantly correlated with the activities of β-glucuronidase and β-1,4-N-acetylglucosaminidase, whereas non-EcM fungal community characteristics were significantly correlated with β-1,4-glucosidase and β-glucuronidase activities. Furthermore, stochastic processes predominantly drove the assembly of both EcM and non-EcM fungal communities, while deterministic processes exerted greater influence on soil fungal communities in mixed forests compared to pure forests. Our findings may inform a deeper understanding of how the assembly processes and environmental roles of subterranean fungal communities differ between mixed and pure plantations and may provide insights for how to promote forest sustainability in subtropical areas.
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Affiliation(s)
- Xinghao Tang
- Fujian Agriculture and Forestry University, Fuzhou, 350002, China; Fujian Academy of Forestry Sciences, Fuzhou, 350012, China
| | - Juanjuan Yang
- Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Danhua Lin
- Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Huazhang Lin
- Fujian Datian Taoyuan State-owned Forest Farm, Sanming, 366199, China
| | - Xiangxi Xiao
- Fujian Academy of Forestry Sciences, Fuzhou, 350012, China
| | - Sensen Chen
- Fujian Datian Taoyuan State-owned Forest Farm, Sanming, 366199, China
| | - Yunpeng Huang
- Fujian Academy of Forestry Sciences, Fuzhou, 350012, China
| | - Xin Qian
- Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
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Hewitt RE, DeVan MR, Taylor DL, Mack MC. Root-associated fungi and acquisitive root traits facilitate permafrost nitrogen uptake from long-term experimentally warmed tundra. THE NEW PHYTOLOGIST 2024; 242:1704-1716. [PMID: 38273466 DOI: 10.1111/nph.19521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 11/27/2023] [Indexed: 01/27/2024]
Abstract
Root-associated fungi (RAF) and root traits regulate plant acquisition of nitrogen (N), which is limiting to growth in Arctic ecosystems. With anthropogenic warming, a new N source from thawing permafrost has the potential to change vegetation composition and increase productivity, influencing climate feedbacks. Yet, the impact of warming on tundra plant root traits, RAF, and access to permafrost N is uncertain. We investigated the relationships between RAF, species-specific root traits, and uptake of N from the permafrost boundary by tundra plants experimentally warmed for nearly three decades at Toolik Lake, Alaska. Warming increased acquisitive root traits of nonmycorrhizal and mycorrhizal plants. RAF community composition of ericoid (ERM) but not ectomycorrhizal (ECM) shrubs was impacted by warming and correlated with root traits. RAF taxa in the dark septate endophyte, ERM, and ECM guilds strongly correlated with permafrost N uptake for ECM and ERM shrubs. Overall, a greater proportion of variation in permafrost N uptake was related to root traits than RAF. Our findings suggest that warming Arctic ecosystems will result in interactions between roots, RAF, and newly thawed permafrost that may strongly impact feedbacks to the climate system through mechanisms of carbon and N cycling.
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Affiliation(s)
- Rebecca E Hewitt
- Center for Ecosystem Science and Society, Northern Arizona University, PO Box 5620, Flagstaff, AZ, 86011, USA
- Department of Environmental Studies, Amherst College, Amherst, MA, 01002, USA
| | - M Rae DeVan
- Department of Biology, University of New Mexico, MSC03 2020, Albuquerque, NM, 87131, USA
| | - D Lee Taylor
- Department of Biology, University of New Mexico, MSC03 2020, Albuquerque, NM, 87131, USA
| | - Michelle C Mack
- Center for Ecosystem Science and Society, Northern Arizona University, PO Box 5620, Flagstaff, AZ, 86011, USA
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Karst J, Jones MD, Hoeksema JD. Positive citation bias and overinterpreted results lead to misinformation on common mycorrhizal networks in forests. Nat Ecol Evol 2023; 7:501-511. [PMID: 36782032 DOI: 10.1038/s41559-023-01986-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 01/06/2023] [Indexed: 02/15/2023]
Abstract
A common mycorrhizal network (CMN) is formed when mycorrhizal fungal hyphae connect the roots of multiple plants of the same or different species belowground. Recently, CMNs have captured the interest of broad audiences, especially with respect to forest function and management. We are concerned, however, that recent claims in the popular media about CMNs in forests are disconnected from evidence, and that bias towards citing positive effects of CMNs has developed in the scientific literature. We first evaluated the evidence supporting three common claims. The claims that CMNs are widespread in forests and that resources are transferred through CMNs to increase seedling performance are insufficiently supported because results from field studies vary too widely, have alternative explanations or are too limited to support generalizations. The claim that mature trees preferentially send resources and defence signals to offspring through CMNs has no peer-reviewed, published evidence. We next examined how the results from CMN research are cited and found that unsupported claims have doubled in the past 25 years; a bias towards citing positive effects may obscure our understanding of the structure and function of CMNs in forests. We conclude that knowledge on CMNs is presently too sparse and unsettled to inform forest management.
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Affiliation(s)
- Justine Karst
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada.
| | - Melanie D Jones
- Department of Biology, University of British Columbia, Kelowna, British Columbia, Canada
| | - Jason D Hoeksema
- Department of Biology, University of Mississippi, Oxford, MS, USA
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DeVan MR, Johnstone JF, Mack MC, Hollingsworth TN, Taylor DL. Host identity affects the response of mycorrhizal fungal communities to high severity fires in Alaskan boreal forests. FUNGAL ECOL 2023. [DOI: 10.1016/j.funeco.2022.101222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Zhao W, Wang X, Howard MM, Kou Y, Liu Q. Functional shifts in soil fungal communities regulate differential tree species establishment during subalpine forest succession. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 861:160616. [PMID: 36462659 DOI: 10.1016/j.scitotenv.2022.160616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 11/27/2022] [Accepted: 11/27/2022] [Indexed: 06/17/2023]
Abstract
Soil fungi can differentially affect plant performance and community dynamics. While fungi play key roles in driving the plant-soil feedbacks (PSFs) that promote grassland succession, it remains unclear how the fungi-mediated PSFs affect tree species establishment during forest succession. We inoculated pioneer broadleaf (Betula platyphylla and Betula albosinensis) and nonpioneer coniferous tree seedlings (Picea asperata and Abies faxoniana) with fungal-dominated rooting zone soils collected from dominant plant species of early-, mid- and late-successional stages in a subalpine forest, and compared their biomass and fungal communities. All tree species accumulated abundant pathogenic fungi in early-successional inoculated soil, which generated negative biotic feedbacks and lowered seedling biomass. High levels of soil ectomycorrhizal fungi from mid- and late-successional stages resulted in positive biotic PSFs and strongly facilitated slow-growing coniferous seedling performance to favour successional development. B. albosinensis also grew better in mid- and late-successional soils with fewer pathogenic fungi than in early-successional soil, indicating its large susceptibility to pathogen attack. In contrast, the growth of another pioneer tree, B. platyphylla, was significantly suppressed in late-successional soil and was mostly driven by saprotrophic fungi, despite the unchanged pathogenic fungal community traits between the two fast-growing species. This unexpected result suggested a host specificity-dependent mechanism involved in the different impacts of fungal pathogens on host trees. Our findings reveal a critical role of functional shifts in soil fungal communities in mediating differential PSFs of tree species across successional stages, which should be considered to improve the prediction and management of community development following forest disturbances.
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Affiliation(s)
- Wenqiang Zhao
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
| | - Xiaohu Wang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mia M Howard
- Department of Biology, Indiana University, Bloomington, IN, USA
| | - Yongping Kou
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
| | - Qing Liu
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China.
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Orumaa A, Agan A, Anslan S, Drenkhan T, Drenkhan R, Kauer K, Köster K, Tedersoo L, Metslaid M. Long-term effects of forest fires on fungal community and soil properties along a hemiboreal Scots pine forest fire chronosequence. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158173. [PMID: 35988616 DOI: 10.1016/j.scitotenv.2022.158173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 08/16/2022] [Accepted: 08/16/2022] [Indexed: 06/15/2023]
Abstract
We studied long-term effects of forest fires on the dynamics of soil fungal community along a post-fire chronosequence in hemiboreal Scots pine stands in north-western Estonia. Effects of fire on soil and fungi were studied on six sites that differed in time since fire (10, 21, 36, 67, 78 and 181 years ago), without further management interventions. Soil fungal communities along the chronosequence were dominated by soil saprotrophs and ectomycorrhizal (EcM) fungi. Across the chronosequence, the most dominant phylum was Ascomycota. The most abundant OTUs were identified as Umbelopsis sp., Hyaloscyphaceae sp. and Pezoloma ericae with relative abundances of 9.5, 8.9 and 6.8 %, respectively. Fungal species richness was similar among sample areas except in the area where fire occurred 36 years ago, where it was significantly lower. There were considerable differences in EcM fungal species composition along the chronosequence. The most recently burned site had Piloderma sphaerosporum, Pseudotomentella sp. and Clavulinaceae sp. as most abundant EcM OTUs while in three oldest burned areas Clavulinaceae sp. and Cortinarius sp. were abundant. Soil C and N stocks were lower in the most recently burned area but differences with other areas were not statistically significant. Soil pH had a significant effect on fungal species composition. Older areas had substantially lower pH compared to more recently burned areas.
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Affiliation(s)
- Argo Orumaa
- Institute of Forestry and Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, 51006 Tartu, Estonia.
| | - Ahto Agan
- Institute of Forestry and Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, 51006 Tartu, Estonia; Institute of Ecology and Earth Sciences, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
| | - Sten Anslan
- Institute of Ecology and Earth Sciences, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
| | - Tiia Drenkhan
- Institute of Forestry and Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, 51006 Tartu, Estonia; Forest Health and Biodiversity, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland
| | - Rein Drenkhan
- Institute of Forestry and Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, 51006 Tartu, Estonia
| | - Karin Kauer
- Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 5, 51006 Tartu, Estonia
| | - Kajar Köster
- Department of Environmental and Biological Sciences, University of Eastern Finland, Yliopistokatu 7 (Natura), 80130 Joensuu, Finland
| | - Leho Tedersoo
- Institute of Ecology and Earth Sciences, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
| | - Marek Metslaid
- Institute of Forestry and Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, 51006 Tartu, Estonia
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Zhang Y, Wang Q, Xu L, Ma S, Cui D, Zhu K, Feng W. Mixed conifer-broadleaf trees on arbuscular mycorrhizal and ectomycorrhizal communities in rhizosphere soil of different plantation stands in the temperate zone, Northeast China. Front Microbiol 2022; 13:986515. [PMID: 36238594 PMCID: PMC9551461 DOI: 10.3389/fmicb.2022.986515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 09/09/2022] [Indexed: 12/03/2022] Open
Abstract
In comparison with ectomycorrhizal (EM) tree species, arbuscular mycorrhizal (AM) trees have different litter quality and nitrogen cycle modes, which may affect mycorrhizal colonization and the community composition and diversity. However, available studies addressing the mycorrhizal fungal colonization rate, diversity and community composition in mixed forest stands composed of AM and EM trees are rare. In the present study, we assessed litter quality, soil physicochemical properties and correlated them with mycorrhizal community characteristics in rhizosphere soils of monoculture and mixture plantation stands of AM tree species (Fraxinus mandschurica Rupr.) and EM tree species (Larix gmelinii Rupr., Picea koraiensis Nakai) in Northeast China. We hypothesized that (1) the effect of mixture pattern on mycorrhizal colonization rate and diversity would change with tree species, (2) the effect of mixture pattern on mycorrhizal community composition would be less pronounced in comparison with that of tree species. We found that mixture did not change AMF colonization rate regardless of mixture identity, whereas mixture and tree species exerted significant effects on EMF colonization rate. For AMF community, both M-AS (Fraxinus mandschurica Rupr. and Picea koraiensis Nakai) and M-AL (Fraxinus mandschurica Rupr. and Larix gmelinii Rupr.) mixtures significantly increased Pielou index and Simpson index, whereas only M-AS significantly increased Sobs. For EMF community, mixture significantly affected examined diversity indices except for Chao1. Mixture significantly shifted AMF and EMF community, and the magnitude was tree species dependent. The dominant genera in AMF and EMF communities in plantation stands were Glomus and Tomentella, respectively. The EnvFit analysis showed that the determinant factors of EMF community are soil moisture, pH, nitrate nitrogen content, dissolved organic nitrogen content, soil organic matter content, soil organic carbon/total nitrogen and litter carbon/total nitrogen. In conclusion, mixed conifer-broadleaf trees significantly changed soil physicochemical properties, litter quality as well as mycorrhizal fungi community diversity and composition.
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Miyamoto Y, Maximov TC, Kononov A, Sugimoto A. Soil propagule banks of ectomycorrhizal fungi associated with <i>Larix cajanderi</i> above the treeline in the Siberian Arctic. MYCOSCIENCE 2022; 63:142-148. [PMID: 37090475 PMCID: PMC10042316 DOI: 10.47371/mycosci.2022.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 05/08/2022] [Accepted: 05/08/2022] [Indexed: 11/16/2022]
Abstract
Microbial symbionts are essential for plant niche expansion into novel habitats. Dormant propagules of ectomycorrhizal (EM) fungi are thought to play an important role in seedling establishment in invasion fronts; however, propagule bank communities above the treeline are poorly understood in the Eurasian Arctic, where treelines are expected to advance under rapid climate change. To investigate the availability of EM fungal propagules, we collected 100 soil samples from Arctic tundra sites and applied bioassay experiments using Larix cajanderi as bait seedlings. We detected 11 EM fungal operational taxonomic units (OTUs) by obtaining entire ITS regions. Suillus clintonianus was the most frequently observed OTU, followed by Cenococcum geophilum and Sebacinales OTU1. Three Suillus and one Rhizopogon species were detected in the bioassay seedlings, indicating the availability of Larix-specific suilloid spores at least 30 km from the contemporary treeline. Spores of S. clintonianus and S. spectabilis remained infective after preservation for 14 mo and heat treatment at 60 °C, implying the durability of the spores. Long-distance dispersal capability and spore resistance to adverse conditions may represent ecological strategies employed by suilloid fungi to quickly associate with emerging seedlings of compatible hosts in treeless habitats.
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Affiliation(s)
| | - Trofim C. Maximov
- Institute for Biological Problems of Cryolithozone, Siberian Branch of Russian Academy of Sciences
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Ibáñez TS, Wardle DA, Gundale MJ, Nilsson MC. Effects of Soil Abiotic and Biotic Factors on Tree Seedling Regeneration Following a Boreal Forest Wildfire. Ecosystems 2021. [DOI: 10.1007/s10021-021-00666-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AbstractWildfire disturbance is important for tree regeneration in boreal ecosystems. A considerable amount of literature has been published on how wildfires affect boreal forest regeneration. However, we lack understanding about how soil-mediated effects of fire disturbance on seedlings occur via soil abiotic properties versus soil biota. We collected soil from stands with three different severities of burning (high, low and unburned) and conducted two greenhouse experiments to explore how seedlings of tree species (Betula pendula, Pinus sylvestris and Picea abies) performed in live soils and in sterilized soil inoculated by live soil from each of the three burning severities. Seedlings grown in live soil grew best in unburned soil. When sterilized soils were reinoculated with live soil, seedlings of P. abies and P. sylvestris grew better in soil from low burn severity stands than soil from either high severity or unburned stands, demonstrating that fire disturbance may favor post-fire regeneration of conifers in part due to the presence of soil biota that persists when fire severity is low or recovers quickly post-fire. Betula pendula did not respond to soil biota and was instead driven by changes in abiotic soil properties following fire. Our study provides strong evidence that high fire severity creates soil conditions that are adverse for seedling regeneration, but that low burn severity promotes soil biota that stimulates growth and potential regeneration of conifers. It also shows that species-specific responses to abiotic and biotic soil characteristics are altered by variation in fire severity. This has important implications for tree regeneration because it points to the role of plant–soil–microbial feedbacks in promoting successful establishment, and potentially successional trajectories and species dominance in boreal forests in the future as fire regimes become increasingly severe through climate change.
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Hewitt RE, Chapin FS, Hollingsworth TN, Mack MC, Rocha AV, Taylor DL. Limited overall impacts of ectomycorrhizal inoculation on recruitment of boreal trees into Arctic tundra following wildfire belie species-specific responses. PLoS One 2020; 15:e0235932. [PMID: 32645087 PMCID: PMC7347221 DOI: 10.1371/journal.pone.0235932] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 06/24/2020] [Indexed: 01/16/2023] Open
Abstract
We tested whether post-fire seedling establishment of common boreal tree and expanding shrub species at treeline and in Arctic tundra is facilitated by co-migration of boreal forest mycorrhizal fungi. Wildfires are anticipated to facilitate biome shifts at the forest-tundra ecotone by improving seedbed conditions for recruiting boreal species; at the same time fire alters the composition and availability of mycorrhizal fungi critical to seedling performance. To determine the role of root-associated fungi (RAF) in post-fire seedling recruitment and future biome shifts, we outplanted four dominant boreal tree and shrub species inoculated with one of three treatments at treeline and in tundra: burned boreal forest, unburned boreal forest, or a control treatment of sterilized inoculum. We compared survivorship, growth, and physiological performance of the seedlings in relation to mycorrhizal inoculum treatment and among host species, characterized the RAF communities based on ITS-rDNA sequencing of individual root tips sampled from surviving seedlings, and tested for correlations between RAF composition and the inoculation treatments, host species, and duration of the experiment. We explored correlations between RAF composition and seedling metrics. Both live and sterile autoclaved inoculation treatments had similar effects on seedling survivorship and growth for all species. RAF composition did not vary by treatment, suggesting that most colonization was due to local fungi. However, seedling traits and growth were correlated with RAF species composition, colonization, and the relative abundance of specific RAF taxa. Picea sp. performance in particular showed strong co-variation with RAF metrics. Our results suggest that mycorrhizal co-migration is not a primary limiting factor to boreal seedling recruitment because the experimental provision of inoculum did not affect seedling recruitment; yet, RAF did influence seedling performance, particularly resident RAF at treeline and in tundra, suggesting that mycorrhizal fungi are important to vegetation processes at the treeline-tundra ecotone.
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Affiliation(s)
- Rebecca E. Hewitt
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, United States of America
| | - F. Stuart Chapin
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
| | - Teresa N. Hollingsworth
- US Forest Service, Pacific Northwest Research Station, Boreal Ecology Cooperative Research Unit, Fairbanks, Alaska, United States of America
| | - Michelle C. Mack
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, United States of America
| | - Adrian V. Rocha
- Department of Biological Sciences and the Environmental Change Initiative, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - D. Lee Taylor
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, United States of America
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Yang T, Tedersoo L, Lin X, Fitzpatrick MC, Jia Y, Liu X, Ni Y, Shi Y, Lu P, Zhu J, Chu H. Distinct fungal successional trajectories following wildfire between soil horizons in a cold-temperate forest. THE NEW PHYTOLOGIST 2020; 227:572-587. [PMID: 32155671 DOI: 10.1111/nph.16531] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 03/02/2020] [Indexed: 06/10/2023]
Abstract
Soil fungi represent a major component of below-ground biodiversity that determines the succession and recovery of forests after disturbance. However, their successional trajectories and driving mechanisms following wildfire remain unclear. We examined fungal biomass, richness, composition and enzymes across three soil horizons (Oe, A1 and A2) along a near-complete fire chronosequence (1, 2, 8, 14, 30, 49 and c. 260 yr) in cold-temperate forests of the Great Khingan Mountains, China. The importance of soil properties, spatial distance and tree composition were also tested. Ectomycorrhizal fungal richness and β-glucosidase activity were strongly reduced by burning and significantly increased with 'time since fire' in the Oe horizon but not in the mineral horizons. Time since fire and soil C : N ratio were the primary drivers of fungal composition in the Oe and A1/A2 horizons, respectively. Ectomycorrhizal fungal composition was remarkably sensitive to fire history in the Oe horizon, while saprotroph community was strongly affected by time since fire in the deeper soil horizon and this effect emerged 18 years after fire in the A2 horizon. Our study demonstrates pronounced horizon-dependent successional trajectories following wildfire and indicates interactive effects of time since fire, soil stoichiometry and spatial distance in the reassembly of below-ground fungal communities in a cold and fire-prone region.
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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
| | - Leho Tedersoo
- Natural History Museum, University of Tartu, 14a Ravila, Tartu, 50411, Estonia
| | - Xingwu Lin
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing, 210008, China
| | - Matthew C Fitzpatrick
- Appalachian Laboratory, University of Maryland Centre for Environmental Science, Frostburg, MD, 21531, USA
| | - Yunsheng Jia
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing, 210008, China
| | - Xu Liu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing, 210008, China
| | - Yingying Ni
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing, 210008, China
| | - 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
| | - Pengpeng Lu
- Microbiology Institute of Shaanxi, Shaanxi Academy of Sciences, Xiying Road 76, Xi'an, 710043, China
| | - Jianguo Zhu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing, 210008, 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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Hughes KW, Case A, Matheny PB, Kivlin S, Petersen RH, Miller AN, Iturriaga T. Secret lifestyles of pyrophilous fungi in the genus Sphaerosporella. AMERICAN JOURNAL OF BOTANY 2020; 107:876-885. [PMID: 32496601 PMCID: PMC7384086 DOI: 10.1002/ajb2.1482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 03/03/2020] [Indexed: 05/07/2023]
Abstract
PREMISE Pyrophilous fungi form aboveground fruiting structures (ascocarps) following wildfires, but their ecology, natural history, and life cycles in the absence of wildfires are largely unknown. Sphaerosporella is considered to be pyrophilous. This study explores Sphaerosporella ascocarp appearance following a rare 2016 wildfire in the Great Smoky Mountains National Park (GSMNP), compares the timing of ascocarp formation with recovery of Sphaerosporella DNA sequences in soils, and explores the association of Sphaerosporella with post-fire Table Mountain pine (Pinus pungens) seedlings. METHODS Burned sites in the GSMNP were surveyed for pyrophilous fungal ascocarps over 2 years. Ascocarps, mycorrhizae, and endophyte cultures were evaluated morphologically and by Sanger sequencing of the nuclear ribosomal ITS gene region (fungal barcode; Schoch et al., 2012). DNA from soil cores was subjected to Illumina sequencing. RESULTS The timing and location of post-fire Sphaerosporella ascocarp formation was correlated with recovery of Sphaerosporella DNA sequences in soils. Genetic markers (fungal barcode) of Sphaerosporella were also recovered from mycorrhizal root tips and endophyte cultures from seedlings of Pinus pungens. CONCLUSIONS This study demonstrates that Sphaerosporella species, in the absence of fire, are biotrophic, forming both mycorrhizal and endophytic associations with developing Pinus pungens seedlings and may persist in nature in the absence of wildfire as a conifer symbiont. We speculate that Sphaerosporella may fruit only after the host plant is damaged or destroyed and that after wildfires, deep roots, needle endophytes, or heat-resistant spores could serve as a source of soil mycelium.
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Affiliation(s)
- Karen W. Hughes
- Department of Ecology and Evolutionary BiologyUniversity of TennesseeKnoxvilleTN37996USA
| | - Alexis Case
- Department of Ecology and Evolutionary BiologyUniversity of TennesseeKnoxvilleTN37996USA
| | - P. Brandon Matheny
- Department of Ecology and Evolutionary BiologyUniversity of TennesseeKnoxvilleTN37996USA
| | - Stephanie Kivlin
- Department of Ecology and Evolutionary BiologyUniversity of TennesseeKnoxvilleTN37996USA
| | - Ronald H. Petersen
- Department of Ecology and Evolutionary BiologyUniversity of TennesseeKnoxvilleTN37996USA
| | - Andrew N. Miller
- Illinois Natural History SurveyUniversity of Illinois Urbana‐Champaign1816 South Oak StreetChampaignIL61820USA
| | - Teresa Iturriaga
- School of Integrated Plant ScienceCornell University334 Plant Science BuildingIthacaNY14853‐5904USA
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13
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Ectomycorrhizal Fungi: Participation in Nutrient Turnover and Community Assembly Pattern in Forest Ecosystems. FORESTS 2020. [DOI: 10.3390/f11040453] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Ectomycorrhizal fungi (EcMF) are involved in soil nutrient cycling in forest ecosystems. These fungi can promote the uptake of nutrients (e.g., nitrogen (N) and phosphorus (P)) and water by host plants, as well as facilitate host plant growth and resistance to stresses and diseases, thereby maintaining the aboveground primary productivity of forest ecosystems. Moreover, EcMF can acquire the carbon (C) sources needed for their growth from the host plants. The nutrient regulation mechanisms of EcMF mainly include the decay of soil organic matter via enzymatic degradation, nonenzymatic mechanism (Fenton chemistry), and priming effects, which in turn promote C and N cycling. At the same time, EcMF can secrete organic acids and phosphatases to improve the availability of soil P, or increase mycelium inputs to facilitate plant acquisition of P. The spatiotemporal distribution of EcMF is influenced by a combination of historical factors and contemporary environmental factors. The community of EcMF is associated with various factors, such as climate change, soil conditions, and host distribution. Under global climate change, investigating the relationships between the nutrient cycling functions of EcMF communities and their distribution patterns under various spatiotemporal scales is conducive to more accurate assessments of the ecological effects of EcMF on the sustainable development of forest.
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14
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Bai Z, Yuan ZQ, Wang DM, Fang S, Ye J, Wang XG, Yuan HS. Ectomycorrhizal fungus-associated determinants jointly reflect ecological processes in a temperature broad-leaved mixed forest. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 703:135475. [PMID: 31767296 DOI: 10.1016/j.scitotenv.2019.135475] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 11/05/2019] [Accepted: 11/09/2019] [Indexed: 06/10/2023]
Abstract
Ectomycorrhizal (ECM) fungi are closely related to vegetation compositions, edaphic properties, and site-specific processes. However, the coevolutionary mechanisms underlying the spatial distributions in floristic and ECM fungal composition in the context of biotic adaptations and abiotic variances remain unclear. We combine a total of 25 ECM fungus-associated environmental variables to impose three types of composite scores and then quantify the environmental gradients of geographical site, soil chemical property and vegetation functional trait across 122 grids of 20 m × 20 m in a 25-hm2 forest plot. Significant dissimilarities in vegetational and ECM fungal abundance and composition existed along the above environmental gradients. Specifically, a contrasting floristic distribution (e.g., Betula platyphylla vs. Tilia mandshurica) existed between the northeastern and southwestern areas and was closely related to the nutrient and moisture gradients (with high levels in the west and low levels in the east). Furthermore, the ECM fungal communities were more abundant in the nutrient-poor and low-moisture environments than in the nutrient-rich and high-moisture environments, and the mixed-forest in the middle-gradient sites between the northeastern and southwestern areas harbored the highest ECM fungal diversity. These findings suggest that predictable within-site vegetation succession is closely related to ECM-associated determinants and the natural spatial heterogeneity of edaphic properties at a local scale.
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Affiliation(s)
- Zhen Bai
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, PR China
| | - Zuo-Qiang Yuan
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, PR China
| | - Dong-Mei Wang
- School of pharmacy, Shenyang Pharmaceutical University, 72 Wenhua Road, Shenyang 110016, PR China
| | - Shuai Fang
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, PR China
| | - Ji Ye
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, PR China
| | - Xu-Gao Wang
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, PR China.
| | - Hai-Sheng Yuan
- CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110164, PR China.
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15
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Day NJ, Dunfield KE, Johnstone JF, Mack MC, Turetsky MR, Walker XJ, White AL, Baltzer JL. Wildfire severity reduces richness and alters composition of soil fungal communities in boreal forests of western Canada. GLOBAL CHANGE BIOLOGY 2019; 25:2310-2324. [PMID: 30951220 DOI: 10.1111/gcb.14641] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 02/27/2019] [Accepted: 03/28/2019] [Indexed: 06/09/2023]
Abstract
Wildfire is the dominant disturbance in boreal forests and fire activity is increasing in these regions. Soil fungal communities are important for plant growth and nutrient cycling postfire but there is little understanding of how fires impact fungal communities across landscapes, fire severity gradients, and stand types in boreal forests. Understanding relationships between fungal community composition, particularly mycorrhizas, and understory plant composition is therefore important in predicting how future fire regimes may affect vegetation. We used an extreme wildfire event in boreal forests of Canada's Northwest Territories to test drivers of fungal communities and assess relationships with plant communities. We sampled soils from 39 plots 1 year after fire and 8 unburned plots. High-throughput sequencing (MiSeq, ITS) revealed 2,034 fungal operational taxonomic units. We found soil pH and fire severity (proportion soil organic layer combusted), and interactions between these drivers were important for fungal community structure (composition, richness, diversity, functional groups). Where fire severity was low, samples with low pH had higher total fungal, mycorrhizal, and saprotroph richness compared to where severity was high. Increased fire severity caused declines in richness of total fungi, mycorrhizas, and saprotrophs, and declines in diversity of total fungi and mycorrhizas. The importance of stand age (a surrogate for fire return interval) for fungal composition suggests we could detect long-term successional patterns even after fire. Mycorrhizal and plant community composition, richness, and diversity were weakly but significantly correlated. These weak relationships and the distribution of fungi across plots suggest that the underlying driver of fungal community structure is pH, which is modified by fire severity. This study shows the importance of edaphic factors in determining fungal community structure at large scales, but suggests these patterns are mediated by interactions between fire and forest stand composition.
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Affiliation(s)
- Nicola J Day
- Wilfrid Laurier University, Waterloo, Ontario, Canada
| | | | - Jill F Johnstone
- University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- University of Alaska Fairbanks, Fairbanks, Alaska
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16
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Species composition and colonization of dark septate endophytes are affected by host plant species and soil depth in the Mu Us sandland, northwest China. FUNGAL ECOL 2019. [DOI: 10.1016/j.funeco.2019.01.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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17
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Dresch P, Falbesoner J, Ennemoser C, Hittorf M, Kuhnert R, Peintner U. Emerging from the ice-fungal communities are diverse and dynamic in earliest soil developmental stages of a receding glacier. Environ Microbiol 2019; 21:1864-1880. [PMID: 30888722 PMCID: PMC6849718 DOI: 10.1111/1462-2920.14598] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 03/04/2019] [Accepted: 03/04/2019] [Indexed: 11/30/2022]
Abstract
We used amplicon sequencing and isolation of fungi from in-growth mesh bags to identify active fungi in three earliest stages of soil development (SSD) at a glacier forefield (0-3, 9-14, 18-25 years after retreat of glacial ice). Soil organic matter and nutrient concentrations were extremely low, but the fungal diversity was high [220 operational taxonomic units (OTUs)/138 cultivated OTUs]. A clear successional trend was observed along SSDs, and species richness increased with time. Distinct changes in fungal community composition occurred with the advent of vascular plants. Fungal communities of recently deglaciated soil are most distinctive and rather similar to communities typical for cryoconite or ice. This indicates melting water as an important inoculum for native soil. Moreover, distinct seasonal differences were detected in fungal communities. Some fungal taxa, especially of the class Microbotryomycetes, showed a clear preference for winter and early SSD. Our results provide insight into new facets regarding the ecology of fungal taxa, for example, by showing that many fungal taxa might have an alternative, saprobial lifestyle in snow-covered, as supposed for a few biotrophic plant pathogens of class Pucciniomycetes. The isolated fungi include a high proportion of unknown species, which can be formally described and used for experimental approaches.
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Affiliation(s)
- Philipp Dresch
- Institute of MicrobiologyUniversity InnsbruckInnsbruckAustria
| | | | | | | | - Regina Kuhnert
- Institute of MicrobiologyUniversity InnsbruckInnsbruckAustria
| | - Ursula Peintner
- Institute of MicrobiologyUniversity InnsbruckInnsbruckAustria
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18
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Lett S, Dorrepaal E. Global drivers of tree seedling establishment at alpine treelines in a changing climate. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13137] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Signe Lett
- Department of Ecology and Environmental ScienceClimate Impacts Research CentreUmeå University Abisko Sweden
- Terrestrial Ecology SectionDepartment of BiologyUniversity of Copenhagen Copenhagen Denmark
| | - Ellen Dorrepaal
- Department of Ecology and Environmental ScienceClimate Impacts Research CentreUmeå University Abisko Sweden
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19
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Hewitt RE, Hollingsworth TN, Stuart Chapin III F, Lee Taylor D. Fire-severity effects on plant-fungal interactions after a novel tundra wildfire disturbance: implications for arctic shrub and tree migration. BMC Ecol 2016; 16:25. [PMID: 27169473 PMCID: PMC4865011 DOI: 10.1186/s12898-016-0075-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 04/05/2016] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Vegetation change in high latitude tundra ecosystems is expected to accelerate due to increased wildfire activity. High-severity fires increase the availability of mineral soil seedbeds, which facilitates recruitment, yet fire also alters soil microbial composition, which could significantly impact seedling establishment. RESULTS We investigated the effects of fire severity on soil biota and associated effects on plant performance for two plant species predicted to expand into Arctic tundra. We inoculated seedlings in a growth chamber experiment with soils collected from the largest tundra fire recorded in the Arctic and used molecular tools to characterize root-associated fungal communities. Seedling biomass was significantly related to the composition of fungal inoculum. Biomass decreased as fire severity increased and the proportion of pathogenic fungi increased. CONCLUSIONS Our results suggest that effects of fire severity on soil biota reduces seedling performance and thus we hypothesize that in certain ecological contexts fire-severity effects on plant-fungal interactions may dampen the expected increases in tree and shrub establishment after tundra fire.
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Affiliation(s)
- Rebecca E. Hewitt
- />Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775 USA
- />Center for Ecosystem Science and Society, Northern Arizona University, PO Box 5620, Flagstaff, AZ 86011 USA
| | - Teresa N. Hollingsworth
- />US Forest Service, Pacific Northwest Research Station, Boreal Ecology Cooperative Research Unit, Fairbanks, AK 99775 USA
| | - F. Stuart Chapin III
- />Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775 USA
| | - D. Lee Taylor
- />Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775 USA
- />Department of Biology, University of New Mexico, Albuquerque, NM 87131 USA
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