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Kengdo SK, Ahrens B, Tian Y, Heinzle J, Wanek W, Schindlbacher A, Borken W. Increase in carbon input by enhanced fine root turnover in a long-term warmed forest soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 855:158800. [PMID: 36116665 DOI: 10.1016/j.scitotenv.2022.158800] [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: 07/11/2022] [Revised: 08/18/2022] [Accepted: 09/12/2022] [Indexed: 06/15/2023]
Abstract
Fine root litter represents an important carbon input to soils, but the effect of global warming on fine root turnover (FRT) is hardly explored in forest ecosystems. Understanding tree fine roots' response to warming is crucial for predicting soil carbon dynamics and the functioning of forests as a sink for atmospheric carbon dioxide (CO2). We studied fine root production (FRP) with ingrowth cores and used radiocarbon signatures of first-order, second- to third-order, and bulk fine roots to estimate fine root turnover times after 8 and 14 years of soil warming (+4 °C) in a temperate forest. Fine root turnover times of the individual root fractions were estimated with a one-pool model. Soil warming strongly increased fine root production by up to 128 % within one year, but after two years, the production was less pronounced (+35 %). The first-year production was likely very high due to the rapid exploitation of the root-free ingrowth cores. The radiocarbon signatures of fine roots were overall variable among treatments and plots. Soil warming tended to decrease fine root turnover times of all the measured root fractions after 8 and 14 years of warming, and there was a tendency for trees to use older carbon reserves for fine root production in warmed plots. Furthermore, soil warming increased fine root turnover from 50 to 106 g C m-2 yr-1 (based on two different approaches). Our findings suggest that future climate warming may increase carbon input into soils by enhancing fine root turnover. If this increase may partly offset carbon losses by increased mineralization of soil organic matter in temperate forest soils is still unclear and should guide future research.
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Affiliation(s)
- Steve Kwatcho Kengdo
- Department of Soil Ecology, Bayreuth Center of Ecology and Environmental Research (BAYCEER), University of Bayreuth, Dr.-Hans-Frisch-Straße 1-3, 95448 Bayreuth, Germany.
| | - Bernhard Ahrens
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, 07745 Jena, Germany
| | - Ye Tian
- Division of Terrestrial Ecosystem Research, Department of Microbiology and Ecosystem Science, Center of Microbiology and Environmental Systems Science, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria
| | - Jakob Heinzle
- Department of Forest Ecology and Soil, Federal Research and Training Centre for Forests, Natural Hazards and Landscape-BFW, Seckendorff-Gudent Weg 8, 1131 Vienna, Austria
| | - Wolfgang Wanek
- Division of Terrestrial Ecosystem Research, Department of Microbiology and Ecosystem Science, Center of Microbiology and Environmental Systems Science, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria
| | - Andreas Schindlbacher
- Department of Forest Ecology and Soil, Federal Research and Training Centre for Forests, Natural Hazards and Landscape-BFW, Seckendorff-Gudent Weg 8, 1131 Vienna, Austria
| | - Werner Borken
- Department of Soil Ecology, Bayreuth Center of Ecology and Environmental Research (BAYCEER), University of Bayreuth, Dr.-Hans-Frisch-Straße 1-3, 95448 Bayreuth, Germany
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2
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Neumann M, Godbold DL, Hirano Y, Finér L. Improving models of fine root carbon stocks and fluxes in European forests. THE JOURNAL OF ECOLOGY 2020; 108:496-514. [PMID: 32189723 PMCID: PMC7065197 DOI: 10.1111/1365-2745.13328] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 11/11/2019] [Indexed: 06/10/2023]
Abstract
Fine roots and above-ground litterfall play a pivotal role in carbon dynamics in forests. Nonetheless, direct estimation of stocks of fine roots remains methodologically challenging. Models are thus widely used to estimate these stocks and help elucidate drivers of fine root growth and turnover, at a range of scales.We updated a database of fine root biomass, necromass and production derived from 454 plots across European forests. We then compared fine root biomass and production to estimates obtained from 19 different models. Typical input variables used for the models included climate, net primary production, foliage and above-ground biomass, leaf area index (LAI), latitude and/or land cover type. We tested whether performance could be improved by fitting new multiple regression models, and explored effects of species composition and sampling method on estimated fine root biomass.Average fine root biomass was 332 g/m2, and necromass 379 g/m2, for European forests where the average fine root production was 250 g m-2 year-1. Carbon fraction in fine roots averaged 48.4%, and was 1.5% greater in broadleaved species than conifers.Available models were poor predictors of fine root biomass and production. The best performing models assumed proportionality between above- and below-ground compartments, and used remotely sensed LAI or foliage biomass as key inputs. Model performance was improved by use of multiple regressions, which revealed consistently greater biomass and production in stands dominated by broadleaved species as well as in mixed stands even after accounting for climatic differences. Synthesis. We assessed the potential of existing models to estimate fine root biomass and production in European forests. We show that recalibration reduces by about 40% errors in estimates currently produced by the best available models, and increases three-fold explained variation. Our results underline the quantitative significance of fine roots (live and dead) to the global carbon cycle.
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Affiliation(s)
- Mathias Neumann
- Institute of SilvicultureUniversity of Natural Resources and Life SciencesViennaAustria
| | - Douglas L. Godbold
- Institute of Forest EcologyUniversity of Natural Resources and Life SciencesViennaAustria
- Global Change Research CentreAcademy of Sciences of the Czech RepublicPragueCzech Republic
| | - Yasuhiro Hirano
- Graduate School of Environmental StudiesNagoya UniversityNagoyaJapan
| | - Leena Finér
- Natural Resources Institute FinlandJoensuuFinland
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3
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Rainer-Lethaus G, Oberhuber W. Phloem Girdling of Norway Spruce Alters Quantity and Quality of Wood Formation in Roots Particularly Under Drought. FRONTIERS IN PLANT SCIENCE 2018; 9:392. [PMID: 29636766 PMCID: PMC5881222 DOI: 10.3389/fpls.2018.00392] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 03/12/2018] [Indexed: 05/31/2023]
Abstract
Carbon (C) availability plays an essential role in tree growth and wood formation. We evaluated the hypothesis that a decrease in C availability (i) triggers mobilization of C reserves in the coarse roots of Picea abies to maintain growth and (ii) causes modification of wood structure notably under drought. The 6-year-old saplings were subjected to two levels of soil moisture (watered versus drought conditions) and root C status was manipulated by physically blocking phloem transport in the stem at three girdling dates (GDs). Stem girdling was done before the onset of bud break [day of the year (doy) 77], during vigorous aboveground shoot and radial stem growth (GD doy 138), and after cessation of shoot growth (GD doy 190). The effect of blockage of C transport on root growth, root phenology, and wood anatomical traits [cell lumen diameter (CLD) and cell wall thickness (CWT)] in earlywood (EW) and latewood (LW) was determined. To evaluate changes in belowground C status caused by girdling, non-structural carbohydrates (soluble sugars and starch) in coarse roots were determined at the time of girdling and after the growing season. Although fine root mass significantly decreased in response to blockage of phloem C transport, the phenology of root elongation growth was not affected. Surprisingly, radial root growth and CLD of EW tracheids in coarse roots were strikingly increased in drought-stressed trees, when girdling occurred before bud break or during aboveground stem growth. In watered trees, the growth response to girdling was less distinct, but the CWT of EW significantly increased. Starch reserves in the roots of girdled trees significantly decreased in both soil moisture treatments and at all GDs. We conclude that (i) radial growth and wood development in coarse roots of P. abies saplings are not only dependent on current photosynthates, and (ii) blockage of phloem transport induces physiological changes that outweigh drought effects imposed on root cambial activity and cell differentiation.
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Affiliation(s)
| | - Walter Oberhuber
- Department of Botany, University of Innsbruck, Innsbruck, Austria
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4
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Ostonen I, Truu M, Helmisaari HS, Lukac M, Borken W, Vanguelova E, Godbold DL, Lõhmus K, Zang U, Tedersoo L, Preem JK, Rosenvald K, Aosaar J, Armolaitis K, Frey J, Kabral N, Kukumägi M, Leppälammi-Kujansuu J, Lindroos AJ, Merilä P, Napa Ü, Nöjd P, Parts K, Uri V, Varik M, Truu J. Adaptive root foraging strategies along a boreal-temperate forest gradient. THE NEW PHYTOLOGIST 2017; 215:977-991. [PMID: 28586137 DOI: 10.1111/nph.14643] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Accepted: 04/30/2017] [Indexed: 05/05/2023]
Abstract
The tree root-mycorhizosphere plays a key role in resource uptake, but also in the adaptation of forests to changing environments. The adaptive foraging mechanisms of ectomycorrhizal (EcM) and fine roots of Picea abies, Pinus sylvestris and Betula pendula were evaluated along a gradient from temperate to subarctic boreal forest (38 sites between latitudes 48°N and 69°N) in Europe. Variables describing tree resource uptake structures and processes (absorptive fine root biomass and morphology, nitrogen (N) concentration in absorptive roots, extramatrical mycelium (EMM) biomass, community structure of root-associated EcM fungi, soil and rhizosphere bacteria) were used to analyse relationships between root system functional traits and climate, soil and stand characteristics. Absorptive fine root biomass per stand basal area increased significantly from temperate to boreal forests, coinciding with longer and thinner root tips with higher tissue density, smaller EMM biomass per root length and a shift in soil microbial community structure. The soil carbon (C) : N ratio was found to explain most of the variability in absorptive fine root and EMM biomass, root tissue density, N concentration and rhizosphere bacterial community structure. We suggest a concept of absorptive fine root foraging strategies involving both qualitative and quantitative changes in the root-mycorrhiza-bacteria continuum along climate and soil C : N gradients.
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Affiliation(s)
- Ivika Ostonen
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
| | - Marika Truu
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
| | | | - Martin Lukac
- School of Agriculture, Policy and Development, University of Reading, Reading, RG6 6AR, UK
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Prague, 165 00, Czech Republic
| | - Werner Borken
- Soil Ecology, University of Bayreuth, Dr.-Hans-Frisch-Straße 1-3, D 95448, Bayreuth, Germany
| | - Elena Vanguelova
- Centre for Ecosystem, Society and Biosecurity Forest Research, Farnham, GU10 4LH, UK
| | - Douglas L Godbold
- Institute of Forest Ecology, University of Natural Resources and Life Sciences, BOKU, 1190, Vienna, Austria
- Global Change Research Institute, Ceské Budejovice, 370 05, Czech Republic
| | - Krista Lõhmus
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
| | - Ulrich Zang
- Soil Ecology, University of Bayreuth, Dr.-Hans-Frisch-Straße 1-3, D 95448, Bayreuth, Germany
| | - Leho Tedersoo
- Natural History Museum and Botanical Garden, University of Tartu, 14a Ravila, Tartu, 50411, Estonia
| | - Jens-Konrad Preem
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
| | - Katrin Rosenvald
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
| | - Jürgen Aosaar
- Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, Tartu, 51014, Estonia
| | - Kęstutis Armolaitis
- Institute of Forestry, Lithuanian Research Centre for Agriculture and Forestry, Liepų str. 1, Kaunas District, LT-53101, Girionys, Lithuania
| | - Jane Frey
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
| | - Naima Kabral
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
| | - Mai Kukumägi
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
| | | | - Antti-Jussi Lindroos
- Natural Resources Institute Finland (Luke), Oulu, 90570, Finland
- Natural Resources Institute Finland (Luke), Helsinki, 00790, Finland
| | - Päivi Merilä
- Natural Resources Institute Finland (Luke), Oulu, 90570, Finland
- Natural Resources Institute Finland (Luke), Helsinki, 00790, Finland
| | - Ülle Napa
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
| | - Pekka Nöjd
- Natural Resources Institute Finland (Luke), Luke c/o Aalto yliopisto, PL 16200, 00076, Aalto, Finland
| | - Kaarin Parts
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
| | - Veiko Uri
- Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, Tartu, 51014, Estonia
| | - Mats Varik
- Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, Tartu, 51014, Estonia
| | - Jaak Truu
- Institute of Ecology and Earth Sciences, University of Tartu, 46 Vanemuise, Tartu, 51014, Estonia
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Weemstra M, Mommer L, Visser EJW, van Ruijven J, Kuyper TW, Mohren GMJ, Sterck FJ. Towards a multidimensional root trait framework: a tree root review. THE NEW PHYTOLOGIST 2016; 211:1159-69. [PMID: 27174359 DOI: 10.1111/nph.14003] [Citation(s) in RCA: 224] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 04/06/2016] [Indexed: 05/03/2023]
Abstract
Contents 1159 I. 1159 II. 1161 III. 1164 IV. 1166 1167 References 1167 SUMMARY: The search for a root economics spectrum (RES) has been sparked by recent interest in trait-based plant ecology. By analogy with the one-dimensional leaf economics spectrum (LES), fine-root traits are hypothesised to match leaf traits which are coordinated along one axis from resource acquisitive to conservative traits. However, our literature review and meta-level analysis reveal no consistent evidence of an RES mirroring an LES. Instead the RES appears to be multidimensional. We discuss three fundamental differences contributing to the discrepancy between these spectra. First, root traits are simultaneously constrained by various environmental drivers not necessarily related to resource uptake. Second, above- and belowground traits cannot be considered analogues, because they function differently and might not be related to resource uptake in a similar manner. Third, mycorrhizal interactions may offset selection for an RES. Understanding and explaining the belowground mechanisms and trade-offs that drive variation in root traits, resource acquisition and plant performance across species, thus requires a fundamentally different approach than applied aboveground. We therefore call for studies that can functionally incorporate the root traits involved in resource uptake, the complex soil environment and the various soil resource uptake mechanisms - particularly the mycorrhizal pathway - in a multidimensional root trait framework.
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Affiliation(s)
- Monique Weemstra
- Forest Ecology and Forest Management group, Wageningen University, 6700 AA, Wageningen, the Netherlands
- Plant Ecology and Nature Conservation group, Wageningen University, 6700 AA, Wageningen, the Netherlands
| | - Liesje Mommer
- Plant Ecology and Nature Conservation group, Wageningen University, 6700 AA, Wageningen, the Netherlands
| | - Eric J W Visser
- Department of Experimental Plant Ecology, Institute for Water and Wetland Research, Radboud University Nijmegen, 6500 GL, Nijmegen, the Netherlands
| | - Jasper van Ruijven
- Plant Ecology and Nature Conservation group, Wageningen University, 6700 AA, Wageningen, the Netherlands
| | - Thomas W Kuyper
- Department of Soil Quality, Wageningen University, 6700 AA, Wageningen, the Netherlands
| | - Godefridus M J Mohren
- Forest Ecology and Forest Management group, Wageningen University, 6700 AA, Wageningen, the Netherlands
| | - Frank J Sterck
- Forest Ecology and Forest Management group, Wageningen University, 6700 AA, Wageningen, the Netherlands
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6
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Angst G, John S, Mueller CW, Kögel-Knabner I, Rethemeyer J. Tracing the sources and spatial distribution of organic carbon in subsoils using a multi-biomarker approach. Sci Rep 2016; 6:29478. [PMID: 27380728 PMCID: PMC4933938 DOI: 10.1038/srep29478] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 06/20/2016] [Indexed: 11/15/2022] Open
Abstract
Soil organic carbon (SOC) from aboveground and belowground sources has rarely been differentiated although it may drive SOC turnover and stabilization due to a presumed differing source dependent degradability. It is thus crucial to better identify the location of SOC from different sources for the parameterization of SOC models, especially in the less investigated subsoils. The aim of this study was to spatially assess contributions of organic carbon from aboveground and belowground parts of beech trees to subsoil organic carbon in a Dystric Cambisol. Different sources of SOC were distinguished by solvent-extractable and hydrolysable lipid biomarkers aided by (14)C analyses of soil compartments <63 μm. We found no effect of the distance to the trees on the investigated parameters. Instead, a vertical zonation of the subsoil was detected. A high contribution of fresh leaf- and root-derived organic carbon to the upper subsoil (leaf- and root-affected zone) indicate that supposedly fast-cycling, leaf-derived SOC may still be of considerable importance below the A-horizon. In the deeper subsoil (root-affected zone), roots were an important source of fresh SOC. Simultaneously, strongly increasing apparent (14)C ages (3860 yrs BP) indicate considerable contribution of SOC that may be inherited from the Pleistocene parent material.
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Affiliation(s)
- Gerrit Angst
- Chair of Soil Science, Technical University of Munich, Emil-Ramann-Straße 2, D-85354 Freising, Germany
| | - Stephan John
- Institute for Geology and Mineralogy, University of Cologne, Zülpicher Straße 49a, D-50674 Cologne, Germany
| | - Carsten W. Mueller
- Chair of Soil Science, Technical University of Munich, Emil-Ramann-Straße 2, D-85354 Freising, Germany
| | - Ingrid Kögel-Knabner
- Chair of Soil Science, Technical University of Munich, Emil-Ramann-Straße 2, D-85354 Freising, Germany
- Institute for Advanced Study, Technical University of Munich, Lichtenbergstraße 2a, D-85748 Garching, Germany
| | - Janet Rethemeyer
- Institute for Geology and Mineralogy, University of Cologne, Zülpicher Straße 49a, D-50674 Cologne, Germany
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Artacho P, Bonomelli C. Changes in fine-root production, phenology and spatial distribution in response to N application in irrigated sweet cherry trees. TREE PHYSIOLOGY 2016; 36:601-17. [PMID: 26888890 PMCID: PMC4886287 DOI: 10.1093/treephys/tpw002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 01/01/2016] [Indexed: 06/05/2023]
Abstract
Factors regulating fine-root growth are poorly understood, particularly in fruit tree species. In this context, the effects of N addition on the temporal and spatial distribution of fine-root growth and on the fine-root turnover were assessed in irrigated sweet cherry trees. The influence of other exogenous and endogenous factors was also examined. The rhizotron technique was used to measure the length-based fine-root growth in trees fertilized at two N rates (0 and 60 kg ha(-1)), and the above-ground growth, leaf net assimilation, and air and soil variables were simultaneously monitored. N fertilization exerted a basal effect throughout the season, changing the magnitude, temporal patterns and spatial distribution of fine-root production and mortality. Specifically, N addition enhanced the total fine-root production by increasing rates and extending the production period. On average, N-fertilized trees had a length-based production that was 110-180% higher than in control trees, depending on growing season. Mortality was proportional to production, but turnover rates were inconsistently affected. Root production and mortality was homogeneously distributed in the soil profile of N-fertilized trees while control trees had 70-80% of the total fine-root production and mortality concentrated below 50 cm depth. Root mortality rates were associated with soil temperature and water content. In contrast, root production rates were primarily under endogenous control, specifically through source-sink relationships, which in turn were affected by N supply through changes in leaf photosynthetic level. Therefore, exogenous and endogenous factors interacted to control the fine-root dynamics of irrigated sweet cherry trees.
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Affiliation(s)
- Pamela Artacho
- Ph.D. Program in Agricultural Sciences, Agronomy and Forestry Faculty, Pontifical Catholic University of Chile, Vicuña Mackenna 4860, 7820436-Macul, Región Metropolitana, Chile;
| | - Claudia Bonomelli
- Pomology and Enology Department, Pontifical Catholic University of Chile, Vicuña Mackenna 4860, 7820436-Macul, Región Metropolitana, Chile
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8
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Brunner I, Herzog C, Dawes MA, Arend M, Sperisen C. How tree roots respond to drought. FRONTIERS IN PLANT SCIENCE 2015; 6:547. [PMID: 26284083 PMCID: PMC4518277 DOI: 10.3389/fpls.2015.00547] [Citation(s) in RCA: 240] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 07/06/2015] [Indexed: 05/17/2023]
Abstract
The ongoing climate change is characterized by increased temperatures and altered precipitation patterns. In addition, there has been an increase in both the frequency and intensity of extreme climatic events such as drought. Episodes of drought induce a series of interconnected effects, all of which have the potential to alter the carbon balance of forest ecosystems profoundly at different scales of plant organization and ecosystem functioning. During recent years, considerable progress has been made in the understanding of how aboveground parts of trees respond to drought and how these responses affect carbon assimilation. In contrast, processes of belowground parts are relatively underrepresented in research on climate change. In this review, we describe current knowledge about responses of tree roots to drought. Tree roots are capable of responding to drought through a variety of strategies that enable them to avoid and tolerate stress. Responses include root biomass adjustments, anatomical alterations, and physiological acclimations. The molecular mechanisms underlying these responses are characterized to some extent, and involve stress signaling and the induction of numerous genes, leading to the activation of tolerance pathways. In addition, mycorrhizas seem to play important protective roles. The current knowledge compiled in this review supports the view that tree roots are well equipped to withstand drought situations and maintain morphological and physiological functions as long as possible. Further, the reviewed literature demonstrates the important role of tree roots in the functioning of forest ecosystems and highlights the need for more research in this emerging field.
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Affiliation(s)
- Ivano Brunner
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorf, Switzerland
| | - Claude Herzog
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorf, Switzerland
- Swiss Federal Institute of Technology ZürichZürich, Switzerland
| | - Melissa A. Dawes
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorf, Switzerland
| | - Matthias Arend
- Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorf, Switzerland
| | - Christoph Sperisen
- Forest Soils and Biogeochemistry, Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorf, Switzerland
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9
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Leifeld J, Meyer S, Budge K, Sebastia MT, Zimmermann M, Fuhrer J. Turnover of grassland roots in mountain ecosystems revealed by their radiocarbon signature: role of temperature and management. PLoS One 2015; 10:e0119184. [PMID: 25734640 PMCID: PMC4347979 DOI: 10.1371/journal.pone.0119184] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 01/26/2015] [Indexed: 11/18/2022] Open
Abstract
Root turnover is an important carbon flux component in grassland ecosystems because it replenishes substantial parts of carbon lost from soil via heterotrophic respiration and leaching. Among the various methods to estimate root turnover, the root's radiocarbon signature has rarely been applied to grassland soils previously, although the value of this approach is known from studies in forest soils. In this paper, we utilize the root's radiocarbon signatures, at 25 plots, in mountain grasslands of the montane to alpine zone of Europe. We place the results in context of a global data base on root turnover and discuss driving factors. Root turnover rates were similar to those of a subsample of the global data, comprising a similar temperature range, but measured with different approaches, indicating that the radiocarbon method gives reliable, plausible and comparable results. Root turnover rates (0.06-1.0 y(-1)) scaled significantly and exponentially with mean annual temperatures. Root turnover rates indicated no trend with soil depth. The temperature sensitivity was significantly higher in mountain grassland, compared to the global data set, suggesting additional factors influencing root turnover. Information on management intensity from the 25 plots reveals that root turnover may be accelerated under intensive and moderate management compared to low intensity or semi-natural conditions. Because management intensity, in the studied ecosystems, co-varied with temperature, estimates on root turnover, based on mean annual temperature alone, may be biased. A greater recognition of management as a driver for root dynamics is warranted when effects of climatic change on belowground carbon dynamics are studied in mountain grasslands.
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Affiliation(s)
- Jens Leifeld
- Agroscope, Climate/Air Pollution Group, Zurich, Switzerland
| | - Stefanie Meyer
- Institute for Geography, Friedrich Schiller Universität, Jena, Germany
| | - Karen Budge
- Independent Researcher, Kirkwall, Orkney, United Kingdom
| | - Maria Teresa Sebastia
- Forest Sciences Centre of Catalonia, Lleida, Spain
- Dept. HBJ, ETSEA, University of Lleida, Lleida, Spain
| | - Michael Zimmermann
- University of Natural Resources and Life Sciences Vienna, Department of Forest and Soil Sciences, Vienna, Austria
| | - Juerg Fuhrer
- Agroscope, Climate/Air Pollution Group, Zurich, Switzerland
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10
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Kubisch P, Hertel D, Leuschner C. Do ectomycorrhizal and arbuscular mycorrhizal temperate tree species systematically differ in root order-related fine root morphology and biomass? FRONTIERS IN PLANT SCIENCE 2015; 6:64. [PMID: 25717334 PMCID: PMC4324066 DOI: 10.3389/fpls.2015.00064] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 01/25/2015] [Indexed: 05/08/2023]
Abstract
While most temperate broad-leaved tree species form ectomycorrhizal (EM) symbioses, a few species have arbuscular mycorrhizas (AM). It is not known whether EM and AM tree species differ systematically with respect to fine root morphology, fine root system size and root functioning. In a species-rich temperate mixed forest, we studied the fine root morphology and biomass of three EM and three AM tree species from the genera Acer, Carpinus, Fagus, Fraxinus, and Tilia searching for principal differences between EM and AM trees. We further assessed the evidence of convergence or divergence in root traits among the six co-occurring species. Eight fine root morphological and chemical traits were investigated in root segments of the first to fourth root order in three different soil depths and the relative importance of the factors root order, tree species and soil depth for root morphology was determined. Root order was more influential than tree species while soil depth had only a small effect on root morphology All six species showed similar decreases in specific root length and specific root area from the 1st to the 4th root order, while the species patterns differed considerably in root tissue density, root N concentration, and particularly with respect to root tip abundance. Most root morphological traits were not significantly different between EM and AM species (except for specific root area that was larger in AM species), indicating that mycorrhiza type is not a key factor influencing fine root morphology in these species. The order-based root analysis detected species differences more clearly than the simple analysis of bulked fine root mass. Despite convergence in important root traits among AM and EM species, even congeneric species may differ in certain fine root morphological traits. This suggests that, in general, species identity has a larger influence on fine root morphology than mycorrhiza type.
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Affiliation(s)
- Petra Kubisch
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute of Plant Sciences, University of Göttingen Göttingen, Germany
| | - Dietrich Hertel
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute of Plant Sciences, University of Göttingen Göttingen, Germany
| | - Christoph Leuschner
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute of Plant Sciences, University of Göttingen Göttingen, Germany
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11
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Kubisch P, Hertel D, Leuschner C. Do ectomycorrhizal and arbuscular mycorrhizal temperate tree species systematically differ in root order-related fine root morphology and biomass? FRONTIERS IN PLANT SCIENCE 2015. [PMID: 25717334 DOI: 10.3389/fpls.2015.0006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
While most temperate broad-leaved tree species form ectomycorrhizal (EM) symbioses, a few species have arbuscular mycorrhizas (AM). It is not known whether EM and AM tree species differ systematically with respect to fine root morphology, fine root system size and root functioning. In a species-rich temperate mixed forest, we studied the fine root morphology and biomass of three EM and three AM tree species from the genera Acer, Carpinus, Fagus, Fraxinus, and Tilia searching for principal differences between EM and AM trees. We further assessed the evidence of convergence or divergence in root traits among the six co-occurring species. Eight fine root morphological and chemical traits were investigated in root segments of the first to fourth root order in three different soil depths and the relative importance of the factors root order, tree species and soil depth for root morphology was determined. Root order was more influential than tree species while soil depth had only a small effect on root morphology All six species showed similar decreases in specific root length and specific root area from the 1st to the 4th root order, while the species patterns differed considerably in root tissue density, root N concentration, and particularly with respect to root tip abundance. Most root morphological traits were not significantly different between EM and AM species (except for specific root area that was larger in AM species), indicating that mycorrhiza type is not a key factor influencing fine root morphology in these species. The order-based root analysis detected species differences more clearly than the simple analysis of bulked fine root mass. Despite convergence in important root traits among AM and EM species, even congeneric species may differ in certain fine root morphological traits. This suggests that, in general, species identity has a larger influence on fine root morphology than mycorrhiza type.
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Affiliation(s)
- Petra Kubisch
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute of Plant Sciences, University of Göttingen Göttingen, Germany
| | - Dietrich Hertel
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute of Plant Sciences, University of Göttingen Göttingen, Germany
| | - Christoph Leuschner
- Plant Ecology and Ecosystems Research, Albrecht von Haller Institute of Plant Sciences, University of Göttingen Göttingen, Germany
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12
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Ahrens B, Hansson K, Solly EF, Schrumpf M. Reconcilable differences: a joint calibration of fine-root turnover times with radiocarbon and minirhizotrons. THE NEW PHYTOLOGIST 2014; 204:932-942. [PMID: 25196967 DOI: 10.1111/nph.12979] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 06/27/2014] [Indexed: 05/29/2023]
Abstract
We used bomb-radiocarbon and raw minirhizotron lifetimes of fine roots (< 0.5 mm in diameter) in the organic layer of Norway spruce (Picea abies) forests in southern Sweden to test if different models are able to reconcile the apparently contradicting turnover time estimates from both techniques. We present a framework based on survival functions that is able to jointly model bomb-radiocarbon and minirhizotron data. At the same time we integrate prior knowledge about biases of both techniques--the classification of dead roots in minirhizotrons and the use of carbon reserves to grow new roots. Two-pool models, either in parallel or in serial setting, were able to reconcile the bomb-radiocarbon and minirhizotron data. These models yielded a mean residence time of 3.80 ± 0.16 yr (mean ± SD). On average 60 ± 2% of fine roots turned over within 0.75 ± 0.10 yr, while the rest was turning over within 8.4 ± 0.2 yr. Bomb-radiocarbon and minirhizotron data alone give a biased estimate of fine-root turnover. The two-pool models allow a mechanistic interpretation for the coexistence of fast- and slow-cycling roots--suberization and branching for the serial-two-pool model and branching due to ectomycorrhizal fungi-root interactions for the parallel-two-pool model.
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Affiliation(s)
- Bernhard Ahrens
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, 07445, Jena, Germany
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13
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Herzog C, Steffen J, Graf Pannatier E, Hajdas I, Brunner I. Nine years of irrigation cause vegetation and fine root shifts in a water-limited pine forest. PLoS One 2014; 9:e96321. [PMID: 24802642 PMCID: PMC4011741 DOI: 10.1371/journal.pone.0096321] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 04/05/2014] [Indexed: 11/19/2022] Open
Abstract
Scots pines (Pinus sylvestris L.) in the inner-Alpine dry valleys of Switzerland have suffered from increased mortality during the past decades, which has been caused by longer and more frequent dry periods. In addition, a proceeding replacement of Scots pines by pubescent oaks (Quercus pubescens Willd.) has been observed. In 2003, an irrigation experiment was performed to track changes by reducing drought pressure on the natural pine forest. After nine years of irrigation, we observed major adaptations in the vegetation and shifts in Scots pine fine root abundance and structure. Irrigation permitted new plant species to assemble and promote canopy closure with a subsequent loss of herb and moss coverage. Fine root dry weight increased under irrigation and fine roots had a tendency to elongate. Structural composition of fine roots remained unaffected by irrigation, expressing preserved proportions of cellulose, lignin and phenolic substances. A shift to a more negative δ13C signal in the fine root C indicates an increased photosynthetic activity in irrigated pine trees. Using radiocarbon (14C) measurement, a reduced mean age of the fine roots in irrigated plots was revealed. The reason for this is either an increase in newly produced fine roots, supported by the increase in fine root biomass, or a reduced lifespan of fine roots which corresponds to an enhanced turnover rate. Overall, the responses belowground to irrigation are less conspicuous than the more rapid adaptations aboveground. Lagged and conservative adaptations of tree roots with decadal lifespans are challenging to detect, hence demanding for long-term surveys. Investigations concerning fine root turnover rate and degradation processes under a changing climate are crucial for a complete understanding of C cycling.
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Affiliation(s)
- Claude Herzog
- Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
- Swiss Federal Institute of Technology Zürich ETH, Zurich, Switzerland
| | - Jan Steffen
- Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
| | | | - Irka Hajdas
- Swiss Federal Institute of Technology Zürich ETH, Zurich, Switzerland
| | - Ivano Brunner
- Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
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14
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Adams TS, Eissenstat DM. The continuous incorporation of carbon into existing Sassafras albidum fine roots and its implications for estimating root turnover. PLoS One 2014; 9:e95321. [PMID: 24788762 PMCID: PMC4008494 DOI: 10.1371/journal.pone.0095321] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 03/26/2014] [Indexed: 11/19/2022] Open
Abstract
Although understanding the timing of the deposition of recent photosynthate into fine roots is critical for determining root lifespan and turnover using isotopic techniques, few studies have directly examined the deposition and subsequent age of root carbon. To gain a better understanding of the timing of the deposition of root carbon, we labeled four individual Sassafras albidum trees with 99% 13C CO2. We then tracked whether the label appeared in roots that were at least two weeks old and no longer elongating, at the time of labeling. We found that not only were the non-structural carbon pools (soluble sugars and starch) of existing first-order tree roots incorporating carbon from current photosynthate, but so were the structural components of the roots, even in roots that were more than one year old at the time of labeling.Our findings imply that carbon used in root structural and nonstructural pools is not derived solely from photosynthate at root initiation and have implications regarding the determination of root age and turnover using isotopic techniques.
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Affiliation(s)
- Thomas S. Adams
- Department of Ecosystem Science and Management and the Ecology Graduate Program, the Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - David M. Eissenstat
- Department of Ecosystem Science and Management and the Ecology Graduate Program, the Pennsylvania State University, University Park, Pennsylvania, United States of America
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15
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Ostonen I, Rosenvald K, Helmisaari HS, Godbold D, Parts K, Uri V, Lõhmus K. Morphological plasticity of ectomycorrhizal short roots in Betula sp and Picea abies forests across climate and forest succession gradients: its role in changing environments. FRONTIERS IN PLANT SCIENCE 2013; 4:335. [PMID: 24032035 PMCID: PMC3759007 DOI: 10.3389/fpls.2013.00335] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 08/09/2013] [Indexed: 05/13/2023]
Abstract
Morphological plasticity of ectomycorrhizal (EcM) short roots (known also as first and second order roots with primary development) allows trees to adjust their water and nutrient uptake to local environmental conditions. The morphological traits (MTs) of short-living EcM roots, such as specific root length (SRL) and area, root tip frequency per mass unit (RTF), root tissue density, as well as mean diameter, length, and mass of the root tips, are good indicators of acclimation. We investigated the role of EcM root morphological plasticity across the climate gradient (48-68°N) in Norway spruce (Picea abies (L.) Karst) and (53-66°N) birch (Betula pendula Roth., B. pubescens Ehrh.) forests, as well as in primary and secondary successional birch forests assuming higher plasticity of a respective root trait to reflect higher relevance of that characteristic in acclimation process. We hypothesized that although the morphological plasticity of EcM roots is subject to the abiotic and biotic environmental conditions in the changing climate; the tools to achieve the appropriate morphological acclimation are tree species-specific. Long-term (1994-2010) measurements of EcM roots morphology strongly imply that tree species have different acclimation-indicative root traits in response to changing environments. Birch EcM roots acclimated along latitude by changing mostly SRL [plasticity index (PI) = 0.60], while spruce EcM roots became adjusted by modifying RTF (PI = 0.68). Silver birch as a pioneer species must have a broader tolerance to environmental conditions across various environments; however, the mean PI of all MTs did not differ between early-successional birch and late-successional spruce. The differences between species in SRL, and RTF, diameter, and length decreased southward, toward temperate forests with more favorable growth conditions. EcM root traits reflected root-rhizosphere succession across forest succession stages.
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Affiliation(s)
- Ivika Ostonen
- Institute of Ecology and Earth Sciences, University of TartuTartu, Estonia
| | - Katrin Rosenvald
- Institute of Ecology and Earth Sciences, University of TartuTartu, Estonia
| | | | | | - Kaarin Parts
- Institute of Ecology and Earth Sciences, University of TartuTartu, Estonia
| | - Veiko Uri
- Institute of Forestry and Rural Engineering, Estonian University of Life SciencesTartu, Estonia
| | - Krista Lõhmus
- Institute of Ecology and Earth Sciences, University of TartuTartu, Estonia
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16
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Terzaghi M, Montagnoli A, Di Iorio A, Scippa GS, Chiatante D. Fine-root carbon and nitrogen concentration of European beech (Fagus sylvatica L.) in Italy Prealps: possible implications of coppice conversion to high forest. FRONTIERS IN PLANT SCIENCE 2013; 4:192. [PMID: 23785374 PMCID: PMC3680728 DOI: 10.3389/fpls.2013.00192] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 05/24/2013] [Indexed: 05/10/2023]
Abstract
Fine-root systems represent a very sensitive plant compartment to environmental changes. Gaining further knowledge about their dynamics would improve soil carbon input understanding. This paper investigates C and N concentrations in fine roots in relation to different stand characteristics resulting from conversion of coppiced forests to high forests. In order to evaluate possible interferences due to different vegetative stages of vegetation, fine-root sampling was repeated six times in each stand during the same 2008 growing season. Fine-root sampling was conducted within three different soil depths (0-10; 10-20; and 20-30 cm). Fine-root traits were measured by means of WinRHIZO software which enable us to separate them into three different diameter classes (0-0.5, 0.5-1.0 and 1.0-2.0 mm). The data collected indicate that N concentration was higher in converted stands than in the coppiced stand whereas C concentration was higher in the coppiced stand than in converted stands. Consequently the fine-root C:N ratio was significantly higher in coppiced than in converted stands and showed an inverse relationship with fine-root turnover rate, confirming a significant change of fine-root status after the conversion of a coppice to high forest.
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Affiliation(s)
- Mattia Terzaghi
- Department of Biotechnology and Life Sciences, University of InsubriaVarese, Italy
| | - Antonio Montagnoli
- Department of Biotechnology and Life Sciences, University of InsubriaVarese, Italy
| | - Antonino Di Iorio
- Department of Biotechnology and Life Sciences, University of InsubriaVarese, Italy
| | - Gabriella S. Scippa
- Department of Science and Technology for Environment and Territory, University of MolisePesche, Italy
| | - Donato Chiatante
- Department of Biotechnology and Life Sciences, University of InsubriaVarese, Italy
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17
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Terzaghi M, Montagnoli A, Di Iorio A, Scippa GS, Chiatante D. Fine-root carbon and nitrogen concentration of European beech (Fagus sylvatica L.) in Italy Prealps: possible implications of coppice conversion to high forest. FRONTIERS IN PLANT SCIENCE 2013. [PMID: 23785374 DOI: 10.1080/11263504.2012.741626] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Fine-root systems represent a very sensitive plant compartment to environmental changes. Gaining further knowledge about their dynamics would improve soil carbon input understanding. This paper investigates C and N concentrations in fine roots in relation to different stand characteristics resulting from conversion of coppiced forests to high forests. In order to evaluate possible interferences due to different vegetative stages of vegetation, fine-root sampling was repeated six times in each stand during the same 2008 growing season. Fine-root sampling was conducted within three different soil depths (0-10; 10-20; and 20-30 cm). Fine-root traits were measured by means of WinRHIZO software which enable us to separate them into three different diameter classes (0-0.5, 0.5-1.0 and 1.0-2.0 mm). The data collected indicate that N concentration was higher in converted stands than in the coppiced stand whereas C concentration was higher in the coppiced stand than in converted stands. Consequently the fine-root C:N ratio was significantly higher in coppiced than in converted stands and showed an inverse relationship with fine-root turnover rate, confirming a significant change of fine-root status after the conversion of a coppice to high forest.
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Affiliation(s)
- Mattia Terzaghi
- Department of Biotechnology and Life Sciences, University of Insubria Varese, Italy
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18
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Yuan ZY, Chen HYH. Indirect methods produce higher estimates of fine root production and turnover rates than direct methods. PLoS One 2012; 7:e48989. [PMID: 23166603 PMCID: PMC3494664 DOI: 10.1371/journal.pone.0048989] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 10/02/2012] [Indexed: 11/19/2022] Open
Abstract
The production and turnover of fine roots play substantial roles in the biogeochemical cycles of terrestrial ecosystems. However, the disparity among the estimates of both production and turnover, particularly due to technical limitations, has been debated for several decades. Here, we conducted a meta-analysis to compare published estimates of fine root production and turnover rates derived from different methods at the same sites and at the same sampling time. On average, the estimates of fine root production and turnover rates were 87% and 124% higher, respectively, by indirect methods than by direct methods. The substantially higher fine root production and turnover estimated by indirect methods, on which most global carbon models are based, indicate the necessity of re-assessing the global carbon model predictions for atmospheric carbon sequestration in soils as a result of the production and turnover of fine roots.
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Affiliation(s)
- Z. Y. Yuan
- Faculty of Natural Resources Management, Lakehead University, Thunder Bay, Ontario, Canada
| | - Han Y. H. Chen
- Faculty of Natural Resources Management, Lakehead University, Thunder Bay, Ontario, Canada
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19
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Forest soil respiration reflects plant productivity across a temperature gradient in the Alps. Oecologia 2012; 170:1143-54. [DOI: 10.1007/s00442-012-2371-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 05/10/2012] [Indexed: 11/25/2022]
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20
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Keel SG, Campbell CD, Högberg MN, Richter A, Wild B, Zhou X, Hurry V, Linder S, Näsholm T, Högberg P. Allocation of carbon to fine root compounds and their residence times in a boreal forest depend on root size class and season. THE NEW PHYTOLOGIST 2012; 194:972-981. [PMID: 22452424 DOI: 10.1111/j.1469-8137.2012.04120.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Fine roots play a key role in the forest carbon balance, but their carbon dynamics remain largely unknown. We pulse labelled 50 m(2) patches of young boreal forest by exposure to (13)CO(2) in early and late summer. Labelled photosynthates were traced into carbon compounds of < 1 and 1-3 mm diameter roots (fine roots), and into bulk tissue of these and first-order roots (root tips). Root tips were the most strongly labelled size class. Carbon allocation to all size classes was higher in late than in early summer; mean residence times (MRTs) in starch increased from 4 to 11 months. In structural compounds, MRTs were 0.8 yr in tips and 1.8 yr in fine roots. The MRT of carbon in sugars was in the range of days. Functional differences within the fine root population were indicated by carbon allocation patterns and residence times. Pronounced allocation of recent carbon and higher turnover rates in tips are associated with their role in nutrient and water acquisition. In fine roots, longer MRTs but high allocation to sugars and starch reflect their role in structural support and storage. Accounting for heterogeneity in carbon residence times will improve and most probably reduce the estimates of fine root production.
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Affiliation(s)
- Sonja G Keel
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), SE-901 83 Umeå, Sweden
- Present address: Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA
| | - Catherine D Campbell
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, SE-901 87 Umeå, Sweden
| | - Mona N Högberg
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), SE-901 83 Umeå, Sweden
| | - Andreas Richter
- Department of Terrestrial Ecosystem Research, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, AT-1090 Vienna, Austria
| | - Birgit Wild
- Department of Terrestrial Ecosystem Research, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, AT-1090 Vienna, Austria
| | - Xuhui Zhou
- Research Institute for the Changing Global Environment, Fudan University, Shanghai 200433 China
- Department of Botany and Microbiology, University of Oklahoma, Norman, OK 73019, USA
| | - Vaughan Hurry
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, SE-901 87 Umeå, Sweden
| | - Sune Linder
- Southern Swedish Forest Research Centre, SLU, PO Box 49, SE-230 53 Alnarp, Sweden
| | - Torgny Näsholm
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), SE-901 83 Umeå, Sweden
| | - Peter Högberg
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), SE-901 83 Umeå, Sweden
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Kennedy P. Ectomycorrhizal fungi and interspecific competition: species interactions, community structure, coexistence mechanisms, and future research directions. THE NEW PHYTOLOGIST 2010; 187:895-910. [PMID: 20673286 DOI: 10.1111/j.1469-8137.2010.03399.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The field of ectomycorrhizal fungal (EMF) ecology has largely developed outside the ecological mainstream, owing in large part to the challenges in studying the structure and dynamics of EMF communities. With advances in molecular identification and other research techniques, however, there has been growing interest among mycologists and ecologists in understanding how different ecological factors affect EMF community structure and diversity. While factors such as soil chemistry and host specificity have long been considered important, an increasing number of laboratory and field studies have documented that interspecific competition also has a major impact on EMF species interactions and may significantly influence EMF community structure. In this review, I examine the progress that has been made in understanding the nature of EMF competition. Currently, there are four conclusions that can be drawn: negative competitive effects are rarely reciprocal; competitive outcomes are environmentally context-dependent; field distributions often reflect competitive interactions; and timing of colonization influences competitive success. In addition, I highlight recent studies documenting links between competitive coexistence and EMF community structure, including checkerboard distributions, lottery models, storage effects, and colonization-competition tradeoffs. Finally, I discuss several aspects of EMF competition needing further investigation and some newer methods with which to address them.
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Affiliation(s)
- Peter Kennedy
- Department of Biology, Lewis and Clark College, 0615 SW Palatine Hill Rd, Portland, OR 97219, USA
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22
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Meinen C, Hertel D, Leuschner C. Root Growth and Recovery in Temperate Broad-Leaved Forest Stands Differing in Tree Species Diversity. Ecosystems 2009. [DOI: 10.1007/s10021-009-9271-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/22/2023]
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