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Jin X, Zhu J, Wei X, Xiao Q, Xiao J, Jiang L, Xu D, Shen C, Liu J, He Z. Adaptation Strategies of Seedling Root Response to Nitrogen and Phosphorus Addition. Plants (Basel) 2024; 13:536. [PMID: 38498541 PMCID: PMC10892864 DOI: 10.3390/plants13040536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 02/11/2024] [Accepted: 02/12/2024] [Indexed: 03/20/2024]
Abstract
The escalation of global nitrogen deposition levels has heightened the inhibitory impact of phosphorus limitation on plant growth in subtropical forests. Plant roots area particularly sensitive tissue to nitrogen and phosphorus elements. Changes in the morphological characteristics of plant roots signify alterations in adaptive strategies. However, our understanding of resource-use strategies of roots in this environment remains limited. In this study, we conducted a 10-month experiment at the Castanopsis kawakamii Nature Reserve to evaluate the response of traits of seedling roots (such as specific root length, average diameter, nitrogen content, and phosphorus content) to nitrogen and phosphorus addition. The aim was to reveal the adaptation strategies of roots in different nitrogen and phosphorus addition concentrations. The results showed that: (1) The single phosphorus and nitrogen-phosphorus interaction addition increased the specific root length, surface area, and root phosphorus content. In addition, single nitrogen addition promotes an increase in the average root diameter. (2) Non-nitrogen phosphorus addition and single nitrogen addition tended to adopt a conservative resource-use strategy to maintain growth under low phosphorus conditions. (3) Under the single phosphorus addition and interactive addition of phosphorus and nitrogen, the roots adopted an acquisitive resource-use strategy to obtain more available phosphorus resources. Accordingly, the adaptation strategy of seedling roots can be regulated by adding appropriate concentrations of nitrogen or phosphorus, thereby promoting the natural regeneration of subtropical forests.
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Affiliation(s)
- Xing Jin
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (X.J.); (J.Z.); (X.W.); (Q.X.); (J.X.); (L.J.); (D.X.)
- Key Laboratory of Ecology and Resource Statistics in Fujian Province, Fuzhou 350002, China
| | - Jing Zhu
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (X.J.); (J.Z.); (X.W.); (Q.X.); (J.X.); (L.J.); (D.X.)
- Key Laboratory of Ecology and Resource Statistics in Fujian Province, Fuzhou 350002, China
| | - Xin Wei
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (X.J.); (J.Z.); (X.W.); (Q.X.); (J.X.); (L.J.); (D.X.)
- Key Laboratory of Ecology and Resource Statistics in Fujian Province, Fuzhou 350002, China
| | - Qianru Xiao
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (X.J.); (J.Z.); (X.W.); (Q.X.); (J.X.); (L.J.); (D.X.)
- Key Laboratory of Ecology and Resource Statistics in Fujian Province, Fuzhou 350002, China
| | - Jingyu Xiao
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (X.J.); (J.Z.); (X.W.); (Q.X.); (J.X.); (L.J.); (D.X.)
- Key Laboratory of Ecology and Resource Statistics in Fujian Province, Fuzhou 350002, China
| | - Lan Jiang
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (X.J.); (J.Z.); (X.W.); (Q.X.); (J.X.); (L.J.); (D.X.)
- Key Laboratory of Ecology and Resource Statistics in Fujian Province, Fuzhou 350002, China
| | - Daowei Xu
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (X.J.); (J.Z.); (X.W.); (Q.X.); (J.X.); (L.J.); (D.X.)
- Key Laboratory of Ecology and Resource Statistics in Fujian Province, Fuzhou 350002, China
| | - Caixia Shen
- School of Economics and Management, Sanming University, Sanming 365000, China;
| | - Jinfu Liu
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (X.J.); (J.Z.); (X.W.); (Q.X.); (J.X.); (L.J.); (D.X.)
- Key Laboratory of Ecology and Resource Statistics in Fujian Province, Fuzhou 350002, China
| | - Zhongsheng He
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (X.J.); (J.Z.); (X.W.); (Q.X.); (J.X.); (L.J.); (D.X.)
- Key Laboratory of Ecology and Resource Statistics in Fujian Province, Fuzhou 350002, China
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Wang X, Xu C, Xiong D, Yao X, Chen T, Jiang Q, Jia L, Fan A, Chen G. Root age-related response of fine root respiration of Chinese fir seedlings to soil warming. Tree Physiol 2022; 42:1177-1187. [PMID: 35043963 DOI: 10.1093/treephys/tpac004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
The variation in fine root respiration with root age provides insight into root adaptation to climate warming, but the mechanism is poorly understood. In this study, we investigated the respiratory response of fine roots (<1 mm and 1-2 mm) of different ages (2-, 4- and 6-month old) of Chinese fir (Cunninghamia lanceolata (Lamb.)) seedlings to soil warming (4 °C above the control using cable heating). Fine roots were excised to measure the specific respiration rate at a reference temperature of 20 °C (SRR20), and root morphological and chemical traits were measured. Soil warming significantly increased SRR20 by 40% compared with the control, potentially indicating limited acclimation on a short time scale (6 months). However, soil warming increased SRR20 significantly in 2-month-old roots (by 72%) compared with 4- and 6-month-old roots, leading to a steeper decline in SRR20 with root age. This result suggests possible increased nutrient uptake efficiency in young fine roots under warmer temperatures. Soil warming significantly increased specific root length (SRL) but not root tissue nitrogen concentration (RTN). The variation in SRR20 between warming treatments, but not across root ages, was predicted by SRL and RTN individually or together. Our findings conclusively indicate that soil warming increased the respiration cost of young fine roots, which was predicted by adjusting for SRL and RTN, indicating that Chinese fir may adopt a faster fine root turnover strategy to enhance nutrient uptake and soil exploitation under warmer temperatures. Future studies should simultaneously investigate age-related root respiration and nutrient uptake in warming experiments to better understand the effects of warming on root metabolic activity.
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Affiliation(s)
- Xiaohong Wang
- Key Laboratory for Subtropical Mountain Ecology (Ministry of Science and Technology and Fujian Province Funded), School of Geographical Sciences, Fujian Normal University, Shangsan road No.8, Cangshan district, Fuzhou 350007, China
| | - Chensen Xu
- Key Laboratory for Subtropical Mountain Ecology (Ministry of Science and Technology and Fujian Province Funded), School of Geographical Sciences, Fujian Normal University, Shangsan road No.8, Cangshan district, Fuzhou 350007, China
| | - Decheng Xiong
- Key Laboratory for Subtropical Mountain Ecology (Ministry of Science and Technology and Fujian Province Funded), School of Geographical Sciences, Fujian Normal University, Shangsan road No.8, Cangshan district, Fuzhou 350007, China
| | - Xiaodong Yao
- Key Laboratory for Subtropical Mountain Ecology (Ministry of Science and Technology and Fujian Province Funded), School of Geographical Sciences, Fujian Normal University, Shangsan road No.8, Cangshan district, Fuzhou 350007, China
| | - Tingting Chen
- Key Laboratory for Subtropical Mountain Ecology (Ministry of Science and Technology and Fujian Province Funded), School of Geographical Sciences, Fujian Normal University, Shangsan road No.8, Cangshan district, Fuzhou 350007, China
| | - Qi Jiang
- Key Laboratory for Subtropical Mountain Ecology (Ministry of Science and Technology and Fujian Province Funded), School of Geographical Sciences, Fujian Normal University, Shangsan road No.8, Cangshan district, Fuzhou 350007, China
| | - Linqiao Jia
- Key Laboratory for Subtropical Mountain Ecology (Ministry of Science and Technology and Fujian Province Funded), School of Geographical Sciences, Fujian Normal University, Shangsan road No.8, Cangshan district, Fuzhou 350007, China
| | - Ailian Fan
- Key Laboratory for Subtropical Mountain Ecology (Ministry of Science and Technology and Fujian Province Funded), School of Geographical Sciences, Fujian Normal University, Shangsan road No.8, Cangshan district, Fuzhou 350007, China
| | - Guangshui Chen
- Key Laboratory for Subtropical Mountain Ecology (Ministry of Science and Technology and Fujian Province Funded), School of Geographical Sciences, Fujian Normal University, Shangsan road No.8, Cangshan district, Fuzhou 350007, China
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3
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Dallstream C, Weemstra M, Soper FM. A framework for fine‐root trait syndromes: syndrome coexistence may support phosphorus partitioning in tropical forests. OIKOS 2022. [DOI: 10.1111/oik.08908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Monique Weemstra
- Ecology and Evolutionary Biology, Univ. of Michigan Ann Arbor MI USA
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An N, Lu N, Fu B, Chen W, Keyimu M, Wang M. Evidence of Differences in Covariation Among Root Traits Across Plant Growth Forms, Mycorrhizal Types, and Biomes. Front Plant Sci 2022; 12:785589. [PMID: 35154176 PMCID: PMC8836870 DOI: 10.3389/fpls.2021.785589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 12/22/2021] [Indexed: 06/02/2023]
Abstract
Fine roots play an important role in plant ecological strategies, adaptation to environmental constraints, and ecosystem functions. Covariation among root traits influence the physiological and ecological processes of plants and ecosystems. Root trait covariation in multiple dimensions at the global scale has been broadly discussed. How fine-root traits covary at the regional scale and whether the covariation is generalizable across plant growth forms, mycorrhizal types, and biomes are largely unknown. Here, we collected six key traits - namely root diameter (RD), specific root length (SRL), root tissue density (RTD), root C content (RCC), root N content (RNC), and root C:N ratio (RCN) - of first- and second-order roots of 306 species from 94 sampling sites across China. We examined the covariation in root traits among different plant growth forms, mycorrhizal types, and biomes using the phylogenetic principal component analysis (pPCA). Three independent dimensions of the covariation in root traits were identified, accounting for 39.0, 26.1, and 20.2% of the total variation, respectively. The first dimension was represented by SRL, RNC, RTD, and RCN, which was in line with the root economics spectrum (RES). The second dimension described a negative relationship between RD and SRL, and the third dimension was represented by RCC. These three main principal components were mainly influenced by biome and mycorrhizal type. Herbaceous and ectomycorrhizal species showed a more consistent pattern with the RES, in which RD, RTD, and RCN were negatively correlated with SRL and RNC within the first axis compared with woody and arbuscular mycorrhizal species, respectively. Our results highlight the roles of plant growth form, mycorrhizal type, and biome in shaping root trait covariation, suggesting that root trait relationships in specific regions may not be generalized from global-scale analyses.
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Affiliation(s)
- Nannan An
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Nan Lu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Bojie Fu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
- Faculty of Geographical Science, Beijing Normal University, Beijing, China
| | - Weiliang Chen
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing, China
| | - Maierdang Keyimu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing, China
| | - Mengyu Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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Freschet GT, Pagès L, Iversen CM, Comas LH, Rewald B, Roumet C, Klimešová J, Zadworny M, Poorter H, Postma JA, Adams TS, Bagniewska‐Zadworna A, Bengough AG, Blancaflor EB, Brunner I, Cornelissen JHC, Garnier E, Gessler A, Hobbie SE, Meier IC, Mommer L, Picon‐Cochard C, Rose L, Ryser P, Scherer‐Lorenzen M, Soudzilovskaia NA, Stokes A, Sun T, Valverde‐Barrantes OJ, Weemstra M, Weigelt A, Wurzburger N, York LM, Batterman SA, Gomes de Moraes M, Janeček Š, Lambers H, Salmon V, Tharayil N, McCormack ML. A starting guide to root ecology: strengthening ecological concepts and standardising root classification, sampling, processing and trait measurements. New Phytol 2021; 232:973-1122. [PMID: 34608637 PMCID: PMC8518129 DOI: 10.1111/nph.17572] [Citation(s) in RCA: 89] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 03/22/2021] [Indexed: 05/17/2023]
Abstract
In the context of a recent massive increase in research on plant root functions and their impact on the environment, root ecologists currently face many important challenges to keep on generating cutting-edge, meaningful and integrated knowledge. Consideration of the below-ground components in plant and ecosystem studies has been consistently called for in recent decades, but methodology is disparate and sometimes inappropriate. This handbook, based on the collective effort of a large team of experts, will improve trait comparisons across studies and integration of information across databases by providing standardised methods and controlled vocabularies. It is meant to be used not only as starting point by students and scientists who desire working on below-ground ecosystems, but also by experts for consolidating and broadening their views on multiple aspects of root ecology. Beyond the classical compilation of measurement protocols, we have synthesised recommendations from the literature to provide key background knowledge useful for: (1) defining below-ground plant entities and giving keys for their meaningful dissection, classification and naming beyond the classical fine-root vs coarse-root approach; (2) considering the specificity of root research to produce sound laboratory and field data; (3) describing typical, but overlooked steps for studying roots (e.g. root handling, cleaning and storage); and (4) gathering metadata necessary for the interpretation of results and their reuse. Most importantly, all root traits have been introduced with some degree of ecological context that will be a foundation for understanding their ecological meaning, their typical use and uncertainties, and some methodological and conceptual perspectives for future research. Considering all of this, we urge readers not to solely extract protocol recommendations for trait measurements from this work, but to take a moment to read and reflect on the extensive information contained in this broader guide to root ecology, including sections I-VII and the many introductions to each section and root trait description. Finally, it is critical to understand that a major aim of this guide is to help break down barriers between the many subdisciplines of root ecology and ecophysiology, broaden researchers' views on the multiple aspects of root study and create favourable conditions for the inception of comprehensive experiments on the role of roots in plant and ecosystem functioning.
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Affiliation(s)
- Grégoire T. Freschet
- CEFEUniv Montpellier, CNRS, EPHE, IRD1919 route de MendeMontpellier34293France
- Station d’Ecologie Théorique et ExpérimentaleCNRS2 route du CNRS09200MoulisFrance
| | - Loïc Pagès
- UR 1115 PSHCentre PACA, site AgroparcINRAE84914Avignon cedex 9France
| | - Colleen M. Iversen
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTN37831USA
| | - Louise H. Comas
- USDA‐ARS Water Management Research Unit2150 Centre Avenue, Bldg D, Suite 320Fort CollinsCO80526USA
| | - Boris Rewald
- Department of Forest and Soil SciencesUniversity of Natural Resources and Life SciencesVienna1190Austria
| | - Catherine Roumet
- CEFEUniv Montpellier, CNRS, EPHE, IRD1919 route de MendeMontpellier34293France
| | - Jitka Klimešová
- Department of Functional EcologyInstitute of Botany CASDukelska 13537901TrebonCzech Republic
| | - Marcin Zadworny
- Institute of DendrologyPolish Academy of SciencesParkowa 562‐035KórnikPoland
| | - Hendrik Poorter
- Plant Sciences (IBG‐2)Forschungszentrum Jülich GmbHD‐52425JülichGermany
- Department of Biological SciencesMacquarie UniversityNorth RydeNSW2109Australia
| | | | - Thomas S. Adams
- Department of Plant SciencesThe Pennsylvania State UniversityUniversity ParkPA16802USA
| | - Agnieszka Bagniewska‐Zadworna
- Department of General BotanyInstitute of Experimental BiologyFaculty of BiologyAdam Mickiewicz UniversityUniwersytetu Poznańskiego 661-614PoznańPoland
| | - A. Glyn Bengough
- The James Hutton InstituteInvergowrie, Dundee,DD2 5DAUK
- School of Science and EngineeringUniversity of DundeeDundee,DD1 4HNUK
| | | | - Ivano Brunner
- Forest Soils and BiogeochemistrySwiss Federal Research Institute WSLZürcherstr. 1118903BirmensdorfSwitzerland
| | - Johannes H. C. Cornelissen
- Department of Ecological ScienceFaculty of ScienceVrije Universiteit AmsterdamDe Boelelaan 1085Amsterdam1081 HVthe Netherlands
| | - Eric Garnier
- CEFEUniv Montpellier, CNRS, EPHE, IRD1919 route de MendeMontpellier34293France
| | - Arthur Gessler
- Forest DynamicsSwiss Federal Research Institute WSLZürcherstr. 1118903BirmensdorfSwitzerland
- Institute of Terrestrial EcosystemsETH Zurich8092ZurichSwitzerland
| | - Sarah E. Hobbie
- Department of Ecology, Evolution and BehaviorUniversity of MinnesotaSt PaulMN55108USA
| | - Ina C. Meier
- Functional Forest EcologyUniversity of HamburgHaidkrugsweg 122885BarsbütelGermany
| | - Liesje Mommer
- Plant Ecology and Nature Conservation GroupDepartment of Environmental SciencesWageningen University and ResearchPO Box 476700 AAWageningenthe Netherlands
| | | | - Laura Rose
- Station d’Ecologie Théorique et ExpérimentaleCNRS2 route du CNRS09200MoulisFrance
- Senckenberg Biodiversity and Climate Research Centre (BiK-F)Senckenberganlage 2560325Frankfurt am MainGermany
| | - Peter Ryser
- Laurentian University935 Ramsey Lake RoadSudburyONP3E 2C6Canada
| | | | - Nadejda A. Soudzilovskaia
- Environmental Biology DepartmentInstitute of Environmental SciencesCMLLeiden UniversityLeiden2300 RAthe Netherlands
| | - Alexia Stokes
- INRAEAMAPCIRAD, IRDCNRSUniversity of MontpellierMontpellier34000France
| | - Tao Sun
- Institute of Applied EcologyChinese Academy of SciencesShenyang110016China
| | - Oscar J. Valverde‐Barrantes
- International Center for Tropical BotanyDepartment of Biological SciencesFlorida International UniversityMiamiFL33199USA
| | - Monique Weemstra
- CEFEUniv Montpellier, CNRS, EPHE, IRD1919 route de MendeMontpellier34293France
| | - Alexandra Weigelt
- Systematic Botany and Functional BiodiversityInstitute of BiologyLeipzig UniversityJohannisallee 21-23Leipzig04103Germany
| | - Nina Wurzburger
- Odum School of EcologyUniversity of Georgia140 E. Green StreetAthensGA30602USA
| | - Larry M. York
- Biosciences Division and Center for Bioenergy InnovationOak Ridge National LaboratoryOak RidgeTN37831USA
| | - Sarah A. Batterman
- School of Geography and Priestley International Centre for ClimateUniversity of LeedsLeedsLS2 9JTUK
- Cary Institute of Ecosystem StudiesMillbrookNY12545USA
| | - Moemy Gomes de Moraes
- Department of BotanyInstitute of Biological SciencesFederal University of Goiás1974690-900Goiânia, GoiásBrazil
| | - Štěpán Janeček
- School of Biological SciencesThe University of Western Australia35 Stirling HighwayCrawley (Perth)WA 6009Australia
| | - Hans Lambers
- School of Biological SciencesThe University of Western AustraliaCrawley (Perth)WAAustralia
| | - Verity Salmon
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTN37831USA
| | - Nishanth Tharayil
- Department of Plant and Environmental SciencesClemson UniversityClemsonSC29634USA
| | - M. Luke McCormack
- Center for Tree ScienceMorton Arboretum, 4100 Illinois Rt. 53LisleIL60532USA
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Primka EJ, Adams TS, Buck A, Eissenstat DM. Topographical shifts in fine root lifespan in a mixed, mesic temperate forest. PLoS One 2021; 16:e0254672. [PMID: 34260660 PMCID: PMC8279377 DOI: 10.1371/journal.pone.0254672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 06/30/2021] [Indexed: 11/18/2022] Open
Abstract
Root lifespan, often is estimated in landscape- and ecosystem-level carbon models using linear approximations. In water manipulation experiments, fine root lifespan can vary with soil water content. Soil water content is generally structured by complex topography, which is largely unaccounted for in landscape- and ecosystem-scale carbon models. Topography governs the range of soil water content experienced by roots which may impact their lifespan. We hypothesized that root lifespan varied nonlinearly across a temperate, mesic, forested catchment due to differences in soil water content associated with topographic position. We expected regions of the landscape that were too wet or too dry would have soils that were not optimal for roots and thus result in shorter root lifespans. Specifically, we hypothesized that root lifespan would be longest in areas that consistently had soil water content in the middle of the soil water content spectrum, while in soils at either very low or very high soil water content, root lifespan would be relatively short. We tested this hypothesis by collecting and analyzing two years of minirhizotron and soil moisture data in plots widely distributed in the Shale Hills catchment of the Susquehanna-Shale Hills Critical Zone Observatory in Pennsylvania. We found that fine root lifespans were longer in traditionally wetter topographic regions, but detected no short term (biweekly) effect of soil moisture on root lifespan. Additionally, depth in soil, soil series, slope face orientation, and season of birth strongly affected root lifespans across the catchment. In contrast, lifespan was unaffected by root diameter or mycorrhizal association. Failure to account for these variables could result in erroneous estimates of fine root lifespan and, consequentially, carbon flux in temperate forested regions.
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Affiliation(s)
- Edward J. Primka
- Department of Ecosystem Science and Management, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Graduate Program in Ecology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Thomas S. Adams
- Department of Plant Science, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Alexandra Buck
- Department of Ecosystem Science and Management, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - David M. Eissenstat
- Department of Ecosystem Science and Management, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Graduate Program in Ecology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
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Pierick K, Leuschner C, Homeier J. Topography as a factor driving small-scale variation in tree fine root traits and root functional diversity in a species-rich tropical montane forest. New Phytol 2021; 230:129-138. [PMID: 33278844 DOI: 10.1111/nph.17136] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
We investigated the variation in tree fine root traits and their functional diversity along a local topographic gradient in a Neotropical montane forest to test if fine root trait variation along the gradient is consistent with the predictions of the root economics spectrum on a shift from acquisitive to conservative traits with decreasing resource supply. We measured five fine root functional traits in 179 randomly selected tree individuals of 100 species and analysed the variation of single traits (using Bayesian phylogenetic multilevel models) and of functional trait diversity with small-scale topography. Fine roots exhibited more conservative traits (thicker diameters, lower specific root length and nitrogen concentration) at upper slope compared with lower slope positions, but the largest proportion of variation (40-80%) was explained by species identity and phylogeny. Fine root functional diversity decreased towards the upper slopes. Our results suggest that local topography and the related soil fertility and moisture gradients cause considerable small-scale variation in fine root traits and functional diversity along tropical mountain slopes, with conservative root traits and greater trait convergence being associated with less favourable soil conditions due to environmental filtering. We provide evidence of a high degree of phylogenetic conservation in fine root traits.
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Affiliation(s)
- Kerstin Pierick
- Plant Ecology and Ecosystems Research, University of Goettingen, Untere Karspüle 2, Göttingen, 37073, Germany
| | - Christoph Leuschner
- Plant Ecology and Ecosystems Research, University of Goettingen, Untere Karspüle 2, Göttingen, 37073, Germany
- Centre for Biodiversity and Sustainable Land Use, University of Goettingen, Büsgenweg 1, Göttingen, 37077, Germany
| | - Jürgen Homeier
- Plant Ecology and Ecosystems Research, University of Goettingen, Untere Karspüle 2, Göttingen, 37073, Germany
- Centre for Biodiversity and Sustainable Land Use, University of Goettingen, Büsgenweg 1, Göttingen, 37077, Germany
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Macdonald CA, Anderson IC, Khachane A, Singh BP, Barton CV, Duursma RA, Ellsworth DS, Singh BK. Plant productivity is a key driver of soil respiration response to climate change in a nutrient-limited soil. Basic Appl Ecol 2021; 50:155-68. [DOI: 10.1016/j.baae.2020.12.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Yang Z, Zhou B, Ge X, Cao Y, Brunner I, Shi J, Li MH. Species-Specific Responses of Root Morphology of Three Co-existing Tree Species to Nutrient Patches Reflect Their Root Foraging Strategies. Front Plant Sci 2021; 11:618222. [PMID: 33569072 PMCID: PMC7868422 DOI: 10.3389/fpls.2020.618222] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 12/30/2020] [Indexed: 06/02/2023]
Abstract
Root foraging strategies of plants may be critical to the competition for nutrient resources in the nutrient patches, but little is known about these of co-existing tree species in subtropical regions. This study aimed to elucidate root foraging strategies of three co-existing tree species in nutrient heterogeneous soils by exploring their root distribution, root morphology, photosynthates allocation and nutrient accumulation. Seedlings of the three tree species [moso bamboo (Phyllostachys edulis), Chinese fir (Cunninghamia lanceolata), and masson pine (Pinus massoniana)] were grown for 8months under one homogeneous soil [uniform nitrogen (N) plus phosphorus (P)] and three heterogeneous soils (localized N supply, localized P supply, or localized N plus P supply). The biomass, root morphological parameters (i.e., root length and root surface area), specific root length (SRL), non-structural carbohydrates (NSCs, i.e., mobile sugar and starch) in roots, total N and total P of plants were measured. The plasticity and distribution of root system were analyzed by calculating the root response ratio (RRR) and root foraging precision (FP), respectively. The results are as follows (i) Chinese fir tended to forage more N by promoting root proliferation in the N-rich patch, while root proliferation of bamboo and pine did not change. For P, bamboo absorbed more P by promoting root proliferation in the P-rich patch. The total P content of Pine and Chinese fir under localized P supply treatment remain the same despite the fact that the root length in the P-rich patch and the FP increased. (ii) Chinese fir foraged more N by increasing root length and decreasing SRL in the NP-rich patch; bamboo foraged more N and P by increasing root length and SRL in the NP-rich patch. The FP and foraging scale (FS) of both bamboo and Chinese fir were significantly improved under localized N plus P treatment. (iii) The concentrations of NSC were positively correlated with root morphological plasticity for moso bamboo and Chinese fir. Our results indicated that higher morphological plasticity is exhibited in moso bamboo and Chinese fir than masson pine in nutrient heterogeneous soils, allowing them to successfully forage for more nutrients.
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Affiliation(s)
- Zhenya Yang
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Bamboo Research, Zhejiang Academy of Forestry, Hangzhou, China
- Qianjiangyuan Forest Ecosystem Research Station, National Forestry and Grassland Administration, Hangzhou, China
| | - Benzhi Zhou
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, China
- Qianjiangyuan Forest Ecosystem Research Station, National Forestry and Grassland Administration, Hangzhou, China
| | - Xiaogai Ge
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, China
- Qianjiangyuan Forest Ecosystem Research Station, National Forestry and Grassland Administration, Hangzhou, China
| | - Yonghui Cao
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, China
- Qianjiangyuan Forest Ecosystem Research Station, National Forestry and Grassland Administration, Hangzhou, China
| | - Ivano Brunner
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
| | - Jiuxi Shi
- Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, China
- Qianjiangyuan Forest Ecosystem Research Station, National Forestry and Grassland Administration, Hangzhou, China
| | - Mai-He Li
- Forest Dynamics, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
- Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, School of Geographical Sciences, Northeast Normal University, Changchun, China
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10
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徐 丽. Research Progress on Effects of Nitrogen Deposition on Dynamics and Morphology of Forest Fine Roots. IJE 2021. [DOI: 10.12677/ije.2021.104078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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11
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董 宁. Research Progress of Forest Fine Root Dynamics and Morphology Respond to Increased Nitrogen Availability. IJE 2021. [DOI: 10.12677/ije.2021.101010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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12
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Zeng W, Xiang W, Zhou B, Ouyang S, Zeng Y, Chen L, Freschet GT, Valverde‐Barrantes OJ, Milcu A. Positive tree diversity effect on fine root biomass: via density dependence rather than spatial root partitioning. OIKOS 2020. [DOI: 10.1111/oik.07777] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Weixian Zeng
- Faculty of Life Science and Technology, Central South Univ. of Forestry and Technology CN‐410004 Changsha Hunan Province PR China
| | - Wenhua Xiang
- Faculty of Life Science and Technology, Central South Univ. of Forestry and Technology CN‐410004 Changsha Hunan Province PR China
- Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem in Hunan Province CN‐438107 Huitong PR China
| | - Bo Zhou
- Faculty of Life Science and Technology, Central South Univ. of Forestry and Technology CN‐410004 Changsha Hunan Province PR China
| | - Shuai Ouyang
- Faculty of Life Science and Technology, Central South Univ. of Forestry and Technology CN‐410004 Changsha Hunan Province PR China
- Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem in Hunan Province CN‐438107 Huitong PR China
| | - Yelin Zeng
- Faculty of Life Science and Technology, Central South Univ. of Forestry and Technology CN‐410004 Changsha Hunan Province PR China
- Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem in Hunan Province CN‐438107 Huitong PR China
| | - Liang Chen
- Faculty of Life Science and Technology, Central South Univ. of Forestry and Technology CN‐410004 Changsha Hunan Province PR China
- Huitong National Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem in Hunan Province CN‐438107 Huitong PR China
| | - Grégoire T. Freschet
- Centre Ecologie Fonctionnelle Evolutive, Univ. Montpellier, CNRS, Univ. Paul Valéry, EPHE, IRD Montpellier France
| | | | - Alexandru Milcu
- Centre Ecologie Fonctionnelle Evolutive, Univ. Montpellier, CNRS, Univ. Paul Valéry, EPHE, IRD Montpellier France
- Ecotron Européen de Montpellier, Univ. Montpellier, CNRS Montferrier sur Lez France
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13
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Pierre S, Litton CM, Giardina CP, Sparks JP, Fahey TJ. Mean annual temperature influences local fine root proliferation and arbuscular mycorrhizal colonization in a tropical wet forest. Ecol Evol 2020; 10:9635-9646. [PMID: 33005336 PMCID: PMC7520179 DOI: 10.1002/ece3.6561] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 05/11/2020] [Accepted: 05/21/2020] [Indexed: 11/25/2022] Open
Abstract
Mean annual temperature (MAT) is an influential climate factor affecting the bioavailability of growth-limiting nutrients nitrogen (N) and phosphorus (P). In tropical montane wet forests, warmer MAT drives higher N bioavailability, while patterns of P availability are inconsistent across MAT. Two important nutrient acquisition strategies, fine root proliferation into bulk soil and root association with arbuscular mycorrhizal fungi, are dependent on C availability to the plant via primary production. The case study presented here tests whether variation in bulk soil N bioavailability across a tropical montane wet forest elevation gradient (5.2°C MAT range) influences (a) morphology fine root proliferation into soil patches with elevated N, P, and N+P relative to background soil and (b) arbuscular mycorrhizal fungal (AMF) colonization of fine roots in patches. We created a fully factorial fertilized root ingrowth core design (N, P, N+P, unfertilized control) representing soil patches with elevated N and P bioavailability relative to background bulk soil. Our results show that percent AMF colonization of roots increased with MAT (r 2 = .19, p = .004), but did not respond to fertilization treatments. Fine root length (FRL), a proxy for root foraging, increased with MAT in N+P-fertilized patches only (p = .02), while other fine root morphological parameters did not respond to the gradient or fertilized patches. We conclude that in N-rich, fine root elongation into areas with elevated N and P declines while AMF abundance increases with MAT. These results indicate a tradeoff between P acquisition strategies occurring with changing N bioavailability, which may be influenced by higher C availability with warmer MAT.
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Affiliation(s)
- Suzanne Pierre
- Department of Ecology and Evolutionary Biology Cornell University Ithaca New York USA
- Department of Integrative Biology University of California, Berkeley Berkeley California USA
| | - Creighton M Litton
- Department of Natural Resources and Environmental Management University of Hawai'i at Manoa Honolulu Hawai'i USA
| | - Christian P Giardina
- Institute of Pacific Islands Forestry Pacific Southwest Research Station US Forest Service Hilo Hawaii USA
| | - Jed P Sparks
- Department of Ecology and Evolutionary Biology Cornell University Ithaca New York USA
| | - Timothy J Fahey
- Department of Natural Resources Cornell University Ithaca New York USA
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Xia Z, He Y, Yu L, Lv R, Korpelainen H, Li C. Sex-specific strategies of phosphorus (P) acquisition in Populus cathayana as affected by soil P availability and distribution. New Phytol 2020; 225:782-792. [PMID: 31487045 DOI: 10.1111/nph.16170] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 08/24/2019] [Indexed: 06/10/2023]
Abstract
Soil phosphorus (P) availability and its distribution influence plant growth and productivity, but how they affect the growth dynamics and sex-specific P acquisition strategies of dioecious plant species is poorly understood. In this study, the impact of soil P availability and its distribution on dioecious Populus cathayana was characterized. P. cathayana males and females were grown under three levels of P supply, and with homogeneous or heterogeneous P distribution. Females had a greater total root length, specific root length (SRL), biomass and foliar P concentration under high P supply. Under P deficiency, males had a smaller root system than females but a greater exudation of soil acid phosphatase, and a higher colonization rate and arbuscular mycorrhizal hyphal biomass, suggesting a better capacity to mine P and a stronger association with arbuscular mycorrhizal fungi to forage P. Heterogeneous P distribution enhanced growth and root length density (RLD) in females. Female root proliferation in P-rich patches was related to increased foliar P assimilation. Localized P application for increasing P availability did not enhance the biomass accumulation and the morphological plasticity of roots in males, but it raised hyphal biomass. The findings herein indicate that sex-specific strategies in P acquisition relate to root morphology, root exudation and mycorrhizal symbioses, and they may contribute to sex-specific resource utilization patterns and niche segregation.
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Affiliation(s)
- Zhichao Xia
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, Zhejiang, China
| | - Yue He
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, Zhejiang, China
| | - Lei Yu
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, Zhejiang, China
| | - Rubing Lv
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, Zhejiang, China
| | - Helena Korpelainen
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, PO Box 27, Helsinki, FI-00014, Finland
| | - Chunyang Li
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, Zhejiang, China
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15
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Mackay DS, Savoy PR, Grossiord C, Tai X, Pleban JR, Wang DR, McDowell NG, Adams HD, Sperry JS. Conifers depend on established roots during drought: results from a coupled model of carbon allocation and hydraulics. New Phytol 2020; 225:679-692. [PMID: 31276231 DOI: 10.1111/nph.16043] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 07/01/2019] [Indexed: 06/09/2023]
Abstract
Trees may survive prolonged droughts by shifting water uptake to reliable water sources, but it is unknown if the dominant mechanism involves activating existing roots or growing new roots during drought, or some combination of the two. To gain mechanistic insights on this unknown, a dynamic root-hydraulic modeling framework was developed that set up a feedback between hydraulic controls over carbon allocation and the role of root growth on soil-plant hydraulics. The new model was tested using a 5 yr drought/heat field experiment on an established piñon-juniper stand with root access to bedrock groundwater. Owing to the high carbon cost per unit root area, modeled trees initialized without adequate bedrock groundwater access experienced potentially lethal declines in water potential, while all of the experimental trees maintained nonlethal water potentials. Simulated trees were unable to grow roots rapidly enough to mediate the hydraulic stress, particularly during warm droughts. Alternatively, modeled trees initiated with root access to bedrock groundwater matched the hydraulics of the experimental trees by increasing their water uptake from bedrock groundwater when soil layers dried out. Therefore, the modeling framework identified a critical mechanism for drought response that required trees to shift water uptake among existing roots rather than growing new roots.
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Affiliation(s)
- D Scott Mackay
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | - Philip R Savoy
- Department of Biology, Duke University, Durham, NC, 27708, USA
| | - Charlotte Grossiord
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903, Birmensdorf, Switzerland
| | - Xiaonan Tai
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | - Jonathan R Pleban
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | - Diane R Wang
- Department of Geography, University at Buffalo, Buffalo, NY, 14261, USA
| | | | - Henry D Adams
- Department of Plant Biology, Ecology, and Evolution, Oklahoma State University, Stillwater, OK, 74078, USA
| | - John S Sperry
- Department of Biology, University of Utah, Salt Lake City, UT, 84112, USA
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16
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Yang S, Cheng R, Xiao W, Shen Y, Wang L, Guo Y, Sun P. Heterogeneity in Decomposition Rates and Nutrient Release in Fine-Root Architecture of Pinus massoniana in the Three Gorges Reservoir Area. Forests 2020; 11:14. [DOI: 10.3390/f11010014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Fine-root decomposition contributes a substantial amount of nitrogen that sustains both plant productivity and soil metabolism, given the high turnover rates and short root life spans of fine roots. Fine-root decomposition and soil carbon and nitrogen cycling were investigated in a 1-year field litterbag study on lower-order roots (1–2 and 3–4) of Pinus massoniana to understand the mechanisms of heterogeneity in decomposition rates and further provide a scientific basis for short-time research on fine-root decomposition and nutrient cycling. Lower-order roots had slower decay rates compared with higher-order roots (5–6). A significantly negative correlation was observed between the decay constant mass remaining and initial N concentrations as well as acid unhydrolyzable residues. Results also showed that in lower-order roots (orders 1–2 and 3–4) with a lower C:N ratio, root residual N was released and then immobilized, whereas in higher-order roots (order 5–6) with a higher C:N ratio, root residual N was immobilized and then released in the initial stage. In the later stage, N immobilization occurred in lower-order roots and N release in higher-order roots, with the C:N ratio gradually decreasing to about 40 in three branching-order classes and then increasing. Our results suggest that lower-order roots decompose more slowly than higher-order roots, which may result from the combined effects of high initial N concentration and poor C quality in lower-order roots. During the decomposition of P. massoniana, N release or N immobilization occurred at the critical C:N ratio.
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17
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Zwetsloot MJ, Goebel M, Paya A, Grams TEE, Bauerle TL. Specific spatio-temporal dynamics of absorptive fine roots in response to neighbor species identity in a mixed beech-spruce forest. Tree Physiol 2019; 39:1867-1879. [PMID: 31504991 DOI: 10.1093/treephys/tpz086] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/07/2019] [Accepted: 07/18/2019] [Indexed: 06/10/2023]
Abstract
Absorptive fine roots are an important driver of soil biogeochemical cycles. Yet, the spatio-temporal dynamics of those roots in the presence of neighboring species remain poorly understood. The aim of this study was to analyze shifts in absorptive fine-root traits in monoculture or mixtures of Fagus sylvatica [L.] and Picea abies [L.] Karst. We hypothesized that root competition would be higher under single-species than mixed-species interactions, leading to changes in (i) root survivorship, diameter and respiration and (ii) spatio-temporal patterns of root growth and death. Using minirhizotron methods, we monitored the timing and location of absorptive fine-root growth and death at an experimental forest in southern Germany from 2011 to 2013. We also measured root respiration in the spring and fall seasons of 2012 and 2013. Our findings show that the absorptive fine roots of F. sylvatica had a 50% higher risk of root mortality and higher respiration rates in the single-species compared to mixed-species zones. These results support our hypothesis that root competition is less intense for F. sylvatica in mixture versus monoculture. We were unable to find confirmation for the same hypothesis for P. abies. To analyze spatio-temporal patterns of absorptive fine-root production and mortality, we used a mixed-effects model considering root depth (space) and seasons (time) simultaneously. This analysis showed that F. sylvatica shifts root production towards shallower soil layers in mixed-species stands, besides significant seasonal fluctuations in root production depths for both species. Ultimately, the impact of neighbor species identity on root traits observed in this study has important implications for where, when and how fast root-facilitated carbon cycling takes place in single-species versus mixed-species forests. In addition, our study highlights the need for inclusion of absorptive fine-root spatio-temporal dynamics when examining belowground plant interactions and biogeochemical cycles.
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Affiliation(s)
- Marie J Zwetsloot
- School of Integrative Plant Science, Cornell University, 236 Tower Road, Ithaca, NY 14853, USA
- Soil Biology Group, Wageningen University, Droevendaalsesteeg 3, 6708 PB Wageningen, the Netherlands
| | - Marc Goebel
- Department of Natural Resources, Cornell University, 111 Fernow Hall, Ithaca, NY 14853, USA
| | - Alex Paya
- School of Integrative Plant Science, Cornell University, 236 Tower Road, Ithaca, NY 14853, USA
| | - Thorsten E E Grams
- Ecophysiology of Plants, Technical University of Munich, Am Hochanger 13, 85354 Freising, Germany
| | - Taryn L Bauerle
- School of Integrative Plant Science, Cornell University, 236 Tower Road, Ithaca, NY 14853, USA
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Song X, Wan F, Chang X, Zhang J, Sun M, Liu Y. Effects of Nutrient Deficiency on Root Morphology and Nutrient Allocation in Pistacia chinensis Bunge Seedlings. Forests 2019; 10:1035. [DOI: 10.3390/f10111035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Plant growth depends on soil mineral elements, a lack of which results in reduced nutrient accumulation leading to poor growth and resistance in plants. Therefore, more information is needed about the response of Pistacia chinensis Bunge (P. chinensis) seedlings to nutrient deficiency. In this study, we investigated how soil nutrient availability affects the nutrient accumulation and root system of P. chinensis seedlings. Seedlings were cultivated under five different nutrient treatments (500 mg, 400 mg, 300 mg, 200 mg, and 100 mg N). Various indices, including seedling growth, nutrient accumulation and root morphology, were analyzed at the end of the growing season. Nutrient deficiency (300 mg, 200 mg, and 100 mg N) reduced the accumulation of nitrogen (N), phosphorus (P) and potassium (K) in roots and stems, while the nutrient proportion of N, P, and K stored in the roots and root to shoot ratio (R/S) was increased at the end of growing season. Root length, root surface area, and root volume of very fine roots (<0.5 mm in diameter) and coarse roots (>3.0 mm in diameter) of the three lower nutrient treatments were significantly lower than those of the two highest nutrient treatments, while no significant difference was detected in the fine roots (1.0–3.0 mm in diameter). Instead, foliar N and K contents in seedlings treated with the two highest treatments were significantly greater than those of the three lower nutrient treatments, resulting in a greater nutrient loss ratio. However, seedlings treated with 100 mg N had significantly higher foliar P content than those treated with 500 mg. Seedlings treated with 300 mg and 200 mg N did not have restricted root nutrient accumulation but did have reduced nutrient accumulation in the stems. The 100 mg N treatment significantly reduced the root nutrient accumulation of N and K. The 500 mg N treatment did not increase the accumulation of nutrients in the storage organs compared with the 400 mg N treatment, but did increase the loss of N and K due to defoliation in autumn. In conclusion, there is a threshold for nutrient accumulation in storage organs at the nursery stage under a specific environment. P. chinensis seedlings reduced the negative effects of nutrient deficiency by promoting root growth, particularly fine roots, and increasing N and K allocation in storage organs.
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Wang Z, Yu K, Lv S, Niklas KJ, Mipam TD, Crowther TW, Umaña MN, Zhao Q, Huang H, Reich PB. The scaling of fine root nitrogen versus phosphorus in terrestrial plants: A global synthesis. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13434] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Zhiqiang Wang
- Institute for Advanced Study Chengdu University Chengdu China
| | - Kailiang Yu
- Institute of Integrative Biology ETH Zürich Zürich Switzerland
| | - Shiqi Lv
- State Key Laboratory of Grassland and Agro‐Ecosystems, School of Life Sciences Lanzhou University Lanzhou China
| | - Karl J. Niklas
- Plant Biology Section, School of Integrative Plant Science Cornell University Ithaca NY USA
| | - Tserang Donko Mipam
- Institute of Qinghai‐Tibetan Plateau Southwest Minzu University Chengdu China
- Key Laboratory for Bio‐Resources and Eco‐Environment, College of Life Sciences Sichuan University Chengdu China
| | | | - María N. Umaña
- Department of Plant Biology Michigan University East Lansing MI USA
| | - Qi Zhao
- Institute for Advanced Study Chengdu University Chengdu China
| | - Heng Huang
- Department of Environmental Science, Policy, and Management University of California Berkeley CA USA
| | - Peter B. Reich
- Department of Forest Resources University of Minnesota St Paul MN USA
- Hawkesbury Institute for the Environment Western Sydney University Sydney NSW Australia
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Shao X, Wang L, Zhang Q, Liu Y, Yang X. Future direction of searching for root economics spectrum: focusing on the fibrous roots “absorptive unit”. Ecosphere 2019. [DOI: 10.1002/ecs2.2716] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Xinliang Shao
- College of Forestry Henan Agricultural University Zhengzhou 450002 China
- Zhengzhou Yaoling Technology Co., Ltd. Zhengzhou 450000 China
| | - Lijun Wang
- College of Light Industry and Food Engineering Guangxi University Nanning 530004 China
| | - Qin Zhang
- Zhengzhou Yaoling Technology Co., Ltd. Zhengzhou 450000 China
| | - Yuhui Liu
- Zhengzhou Yaoling Technology Co., Ltd. Zhengzhou 450000 China
| | - Xitian Yang
- College of Forestry Henan Agricultural University Zhengzhou 450002 China
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Wan F, Ross-davis AL, Shi W, Weston C, Song X, Chang X, Davis AS, Liu Y, Teng F. Subirrigation Effects on Larch Seedling Growth, Root Morphology, and Media Chemistry. Forests 2019; 10:38. [DOI: 10.3390/f10010038] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Subirrigation (SI), where water is provided to container seedlings from below and rises through the growing media via capillary action, is regarded as an environmentally-responsible method of delivering water and fertilizer to nursery-grown plants, resulting in more uniform crops and improved production efficiency. While a concern around adopting this method is that a potential higher salt concentration in the upper layers of growing media under SI may inhibit root growth and result in decreased plant quality, few studies have focused on how root morphology is altered by SI. Therefore, a balanced two-factor factorial design with three rates of fertilization (50, 100, and 150 mg N seedling−1) and two irrigation methods (SI or overhead irrigation (OI)) was used to examine the growth response of Prince Rupprecht’s larch (Larix principis-rupprechtii Mayr) seedlings for one nursery season. Associated changes between rhizosphere electrical conductivity (EC) and root morphology of different root size classes were analyzed. Results show that (1) height, root-collar diameter, and root volume were similar between seedlings grown under SI and OI. However, (2) compared to seedlings receiving OI, SI-seedlings had less root mass, length, and surface area but greater average root diameter (ARD). (3) Morphological differences were evident primarily in root diameter size classes I–III (D ≤ 1.0 mm). (4) Fertilizer rate influenced root length and surface area up to 130 days after sowing but affected ARD throughout the growing season such that seedlings treated with 50 mg N had smaller ARD than seedlings treated with 100 mg N. (5) As the growing season progressed, SI-media had significantly higher EC compared to OI-media and EC increased with increasing fertilizer rate under SI but not under OI. These results indicate that SI can produce larch seedlings of similar height and root collar diameter (RCD) compared to OI, but root systems are smaller overall with fewer small-diameter roots, which may be related to high EC levels in SI-media, which is exacerbated by the use of high rates of fertilizer. Therefore, the EC in the media should be monitored and adjusted by reducing fertilizer rates under SI.
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McCormack ML, Iversen CM. Physical and Functional Constraints on Viable Belowground Acquisition Strategies. Front Plant Sci 2019; 10:1215. [PMID: 31681355 PMCID: PMC6797606 DOI: 10.3389/fpls.2019.01215] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 09/03/2019] [Indexed: 05/19/2023]
Abstract
Since their emergence onto land, terrestrial plants have developed diverse strategies to acquire soil resources. However, we lack a framework that adequately captures how these strategies vary among species. Observations from around the world now allow us to quantify the variation observed in commonly-measured fine-root traits but it is unclear how root traits are interrelated and whether they fall along an "economic" spectrum of acquisitive to conservative strategies. We assessed root trait variation and mycorrhizal colonization rates by leveraging the largest global database of fine-root traits (the Fine-Root Ecology Database; FRED). We also developed a heuristic model to explore the role of mycorrhizal fungi in defining belowground exploration efficiency across a gradient of thin- to thick-diameter roots. In support of the expectations of the "root economic spectrum," we found that root diameter was negatively related to specific root length (Pearson's r=-0.76). However, we found an unexpected negative relationship between root diameter and root tissue density (Pearson's r = -0.40), and we further observed that root nitrogen content was largely unrelated to other economic traits. Mycorrhizal colonization was most closely associated with root diameter (Pearson's r = 0.62) and was unrelated to root tissue density and root nitrogen. The heuristic model demonstrated that while thinner roots have inherently greater capacity to encounter soil resources based on higher surface area per unit mass, the potential for increased associations with mycorrhizal fungi in thicker roots, combined with greater hyphal growth, can result in equally acquisitive strategies for both thin- and thick roots. Taken together, our assessments of root trait variation, trade-offs with mycorrhizal fungi, and broader connections to root longevity allowed us to propose a series of fundamental constraints on belowground resource acquisition strategies. Physical tradeoffs based on root construction (i.e., economic traits) and functional limitations related to the capacity of a root to encounter and acquire soil resources combine to limit the two-dimensional belowground trait space. Within this trait space there remains a diversity of additional variation in root traits that facilitates a wide range of belowground resource acquisition strategies.
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Affiliation(s)
- M. Luke McCormack
- Center for Tree Science, The Morton Arboretum. Lisle, IL, United States
- *Correspondence: M. Luke McCormack,
| | - Colleen M. Iversen
- Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory. Oak Ridge, TN, United States
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Wang P, Yang Y, Mou P, Zhao Q, Li Y. Local root growth and death are mediated by contrasts in nutrient availability and root quantity between soil patches. Proc Biol Sci 2018; 285:20180699. [PMID: 30209222 PMCID: PMC6158519 DOI: 10.1098/rspb.2018.0699] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 08/21/2018] [Indexed: 11/12/2022] Open
Abstract
Plants are thought to be able to regulate local root growth according to its overall nutrient status as well as nutrient contents in a local substrate patch. Therefore, root plastic responses to environmental changes are probably co-determined by local responses of root modules and systematic control of the whole plant. Recent studies showed that the contrast in nutrient availability between different patches could significantly influence the growth and death of local roots. In this study, we further explored, beside nutrient contrast, whether root growth and death in a local patch are also affected by relative root quantity in the patch. We conducted a split-root experiment with different splitting ratios of roots of Canada goldenrod (Solidago canadensis) individuals, as well as high- (5× Hoagland solution versus water) or low- (1× Hoagland solution versus water) contrast nutrient conditions for the split roots. The results showed that root growth decreased in nutrient-rich patches but increased in nutrient-poor patches when more roots co-occurred in the same patches, irrespective of nutrient contrast condition. Root mortality depended on contrasts in both root quantity and nutrients: in the high-nutrient-contrast condition, it increased in nutrient-rich patches but decreased in nutrient-poor patches with increasing root proportion; while in the low-nutrient-contrast condition, it showed the opposite trend. These results demonstrated that root growth and death dynamics were affected by the contrast in both nutrient availability and root quantity between patches. Our study provided ecological evidence that local root growth and death are mediated by both the responses of root modules to a nutrient patch and the whole-plant nutrient status, suggesting that future work investigating root production and turnover should take into account the degree of heterogeneity in nutrient and root distribution.
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Affiliation(s)
- Peng Wang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Yan Yang
- College of Life Sciences, Beijing Normal University, Beijing, People's Republic of China
- Wuhu TianJiaBing Experimental High School, Wuhu, People's Republic of China
| | - Pu Mou
- College of Life Sciences, Beijing Normal University, Beijing, People's Republic of China
| | - Qingzhou Zhao
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Yunbin Li
- College of Environmental and Safety Engineering, Shenyang University of Chemical Technology, Shenyang, People's Republic of China
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Affiliation(s)
- Weile Chen
- Intercollege Graduate Degree Program in Ecology The Pennsylvania State University University Park PA USA
- Department of Ecosystem Science and Management The Pennsylvania State University University Park PA USA
| | - Roger T. Koide
- Intercollege Graduate Degree Program in Ecology The Pennsylvania State University University Park PA USA
- Department of Biology Brigham Young University Provo UT USA
| | - David M. Eissenstat
- Intercollege Graduate Degree Program in Ecology The Pennsylvania State University University Park PA USA
- Department of Ecosystem Science and Management The Pennsylvania State University University Park PA USA
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25
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Trocha LK, Bulaj B, Kutczynska P, Mucha J, Rutkowski P, Zadworny M. The interactive impact of root branch order and soil genetic horizon on root respiration and nitrogen concentration. Tree Physiol 2017; 37:1055-1068. [PMID: 28903525 DOI: 10.1093/treephys/tpx096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 07/05/2017] [Indexed: 06/07/2023]
Abstract
In general, respiration (RS) is highly correlated with nitrogen concentration (N) in plant organs, including roots, which exhibit a positive N-RS relationship. Less is known, however, about the relationship between N and RS in roots of different branch orders within an individual tree along a vertical soil profile; this is especially true in trees with contrasting life strategies, such as pioneer Scots pine (Pinus sylvestris L.) vs mid-successional sessile oak (Quercus petraea Liebl.). In the present research, the impact of root branch order, as represented by those with absorptive vs transporting ability, and soil genetic horizon on root N, RS and the N-RS relationship was examined. Mean RS and total N concentration differed significantly among root branch orders and was significantly higher in absorptive roots than in transporting roots. The soil genetic horizon differentially affected root RS in Scots pine vs sessile oak. The genetic horizon mostly affected RS in absorptive roots of Scots pine and transporting roots in sessile oak. Root N was the highest in absorptive roots and most affected by soil genetic horizon in both tree species. Root N was not correlated with soil N, although N levels were higher in roots growing in fertile soil genetic horizons. Overall, RS in different root branch orders was positively correlated with N in both species. The N-RS relationship in roots, pooled by soil genetic horizon, was significant in both species, but was only significant in sessile oak when roots were pooled by root branch order. In both tree species, a significant interaction was found between the soil genetic horizon and root branch order with root function; however, species-specific responses were found. Both root N, which was unaffected by soil N, and the positive N-RS relationship consistently observed in different genetic horizons suggest that root function prevails over environmental factors, such as soil genetic horizon.
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Affiliation(s)
- Lidia K Trocha
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland
| | - Bartosz Bulaj
- Faculty of Forestry, Poznan University of Life Sciences, Wojska Polskiego 28, 60-637 Poznan, Poland
| | - Paulina Kutczynska
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland
| | - Joanna Mucha
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland
| | - Pawel Rutkowski
- Faculty of Forestry, Poznan University of Life Sciences, Wojska Polskiego 28, 60-637 Poznan, Poland
| | - Marcin Zadworny
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland
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26
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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. New Phytol 2017; 215:977-991. [PMID: 28586137 DOI: 10.1111/nph.14643] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Mosca E, Montecchio L, Barion G, Dal Cortivo C, Vamerali T. Combined effects of thinning and decline on fine root dynamics in a Quercus robur L. forest adjoining the Italian Pre-Alps. Ann Bot 2017; 119:1235-1246. [PMID: 28334145 PMCID: PMC5604614 DOI: 10.1093/aob/mcx007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 12/21/2016] [Indexed: 06/06/2023]
Abstract
AIMS Oak decline is a complex phenomenon, characterized by symptoms of canopy transparency, bark cracks and root biomass reduction. Root health status is one of the first stress indicators, and root turnover is a key process in plant adaptation to unfavourable conditions. In this study, the combined effects of decline and thinning were evaluated on fine root dynamics in an oak forest adjoining the Italian Pre-Alps by comparison of acute declining trees with non-declining trees, both with and without thinning treatment of surrounding trees. METHODS Dynamics of volumetric root length density (RLD V ) and tip density (RTD V ), root tip density per unit length of root (RTD L ), diameter, branching index (BI) and mycorrhizal colonization were monitored by soil coring over 2 years as possible descriptors of decline. KEY RESULTS At the beginning of the experiment, the relationship between canopy transparency and root status was weak, declining trees having slightly lower RLD V (-20 %) and RTD V (-11 %). After a 1 year lag, during which the parameters were almost unaffected, BI and RLD V , together with tip density, tip vitality and mycorrhizal colonization, became the descriptors most representative of both decline class and thinning. Thinning of declining trees increased RLD V (+12 %) and RTD V (+32 %), but reduced tip mycorrhizal colonization and vitality over time compared with non-thinned trees, whereas the opposite occurred in healthy trees, together with a marked decrease in branching. After thinning, there was an initial reduction in the structure of the ectomycorrhizal community, although recovery occurred about 10 months later, regardless of decline severity. CONCLUSIONS Decline causes losses of fine root length, and a moderate recovery can be achieved by thinning, allowing better soil exploration by oak roots. The close correlation between root vitality and mycorrhizal colonization and their deterioration after thinning indicates that decline does not benefit from reduced root competition, excluding the hypothesis of limited water and nutrient availability as a possible cause of the syndrome in this forest.
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Affiliation(s)
- E. Mosca
- Faculty of Science and Technology, Free University of Bolzano, Piazza Università 1, 39100 Bolzano, Italy
- Research and Innovation Centre, Edmund Mach Foundation, Via E. Mach 1, 38010 S. Michele all’Adige, Trento, Italy
| | - L. Montecchio
- Department of Landscape and Agroforestry Systems, University of Padua, Viale dell’Università 16, 35020 Legnaro, Padua, Italy
| | - G. Barion
- Department of Agronomy, Food, Natural Resources, Animals and the Environment, University of Padua, Viale dell’Università 16, 35020 Legnaro, Padua, Italy
| | - C. Dal Cortivo
- Department of Agronomy, Food, Natural Resources, Animals and the Environment, University of Padua, Viale dell’Università 16, 35020 Legnaro, Padua, Italy
| | - T. Vamerali
- Department of Agronomy, Food, Natural Resources, Animals and the Environment, University of Padua, Viale dell’Università 16, 35020 Legnaro, Padua, Italy
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28
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Caplan JS, Stone BWG, Faillace CA, Lafond JJ, Baumgarten JM, Mozdzer TJ, Dighton J, Meiners SJ, Grabosky JC, Ehrenfeld JG. Nutrient foraging strategies are associated with productivity and population growth in forest shrubs. Ann Bot 2017; 119:977-988. [PMID: 28119293 PMCID: PMC5604599 DOI: 10.1093/aob/mcw271] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 12/07/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND AND AIMS Temperate deciduous forest understoreys are experiencing widespread changes in community composition, concurrent with increases in rates of nitrogen supply. These shifts in plant abundance may be driven by interspecific differences in nutrient foraging (i.e. conservative vs. acquisitive strategies) and, thus, adaptation to contemporary nutrient loading conditions. This study sought to determine if interspecific differences in nutrient foraging could help explain patterns of shrub success and decline in eastern North American forests. METHODS Using plants grown in a common garden, fine root traits associated with nutrient foraging were measured for six shrub species. Traits included the mean and skewness of the root diameter distribution, specific root length (SRL), C:N ratio, root tissue density, arbuscular mycorrhizal colonization and foraging precision. Above- and below-ground productivity were also determined for the same plants, and population growth rates were estimated using data from a long-term study of community dynamics. Root traits were compared among species and associations among root traits, measures of productivity and rates of population growth were evaluated. KEY RESULTS Species fell into groups having thick or thin root forms, which correspond to conservative vs. acquisitive nutrient foraging strategies. Interspecific variation in root morphology and tissue construction correlated with measures of productivity and rates of cover expansion. Of the four species with acquisitive traits, three were introduced species that have become invasive in recent decades, and the fourth was a weedy native. In contrast, the two species with conservative traits were historically dominant shrubs that have declined in abundance in eastern North American forests. CONCLUSIONS In forest understoreys of eastern North America, elevated nutrient availability may impose a filter on species success in addition to above-ground processes such as herbivory and overstorey canopy conditions. Shrubs that have root traits associated with rapid uptake of soil nutrients may be more likely to increase in abundance, while species without such traits may be less likely to keep pace with more productive species.
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Affiliation(s)
- Joshua S. Caplan
- Department of Ecology, Evolution, and Natural Resources, Rutgers, The State University of New Jersey, 14 College Farm Road, New Brunswick, NJ 08901, USA
- Department of Biology, Bryn Mawr College, 101 North Merion Avenue, Bryn Mawr, PA 19010, USA
| | - Bram W. G. Stone
- Department of Biology, University of Mississippi, 30 University Avenue, University, MS 38677, USA
| | - Cara A. Faillace
- Department of Ecology, Evolution, and Natural Resources, Rutgers, The State University of New Jersey, 14 College Farm Road, New Brunswick, NJ 08901, USA
| | - Jonathan J. Lafond
- Department of Ecology, Evolution, and Natural Resources, Rutgers, The State University of New Jersey, 14 College Farm Road, New Brunswick, NJ 08901, USA
| | - Joni M. Baumgarten
- Department of Ecology, Evolution, and Natural Resources, Rutgers, The State University of New Jersey, 14 College Farm Road, New Brunswick, NJ 08901, USA
- Rutgers Pinelands Field Station, PO Box 206, New Lisbon, NJ 08064, USA
| | - Thomas J. Mozdzer
- Department of Biology, Bryn Mawr College, 101 North Merion Avenue, Bryn Mawr, PA 19010, USA
| | - John Dighton
- Rutgers Pinelands Field Station, PO Box 206, New Lisbon, NJ 08064, USA
| | - Scott J. Meiners
- Department of Biological Sciences, Eastern Illinois University, 600 Lincoln Avenue, Charleston, IL 61920, USA
| | - Jason C. Grabosky
- Department of Ecology, Evolution, and Natural Resources, Rutgers, The State University of New Jersey, 14 College Farm Road, New Brunswick, NJ 08901, USA
| | - Joan G. Ehrenfeld
- Department of Ecology, Evolution, and Natural Resources, Rutgers, The State University of New Jersey, 14 College Farm Road, New Brunswick, NJ 08901, USA
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Cheng L, Chen W, Adams TS, Wei X, Li L, McCormack ML, DeForest JL, Koide RT, Eissenstat DM. Mycorrhizal fungi and roots are complementary in foraging within nutrient patches. Ecology 2016; 97:2815-2823. [DOI: 10.1002/ecy.1514] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 06/13/2016] [Accepted: 06/13/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Lei Cheng
- College of Life Sciences Zhejiang University Hangzhou 310058 China
- Department of Ecosystem Science and Management The Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Weile Chen
- Department of Ecosystem Science and Management The Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Thomas S. Adams
- Department of Ecosystem Science and Management The Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Xing Wei
- Department of Ecosystem Science and Management The Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Le Li
- Department of Ecosystem Science and Management The Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Michael Luke McCormack
- Department of Ecosystem Science and Management The Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Jared L. DeForest
- Department of Environmental and Plant Biology Ohio University Athens Ohio 45701 USA
| | - Roger T. Koide
- Department of Ecosystem Science and Management The Pennsylvania State University University Park Pennsylvania 16802 USA
- Department of Biology Brigham Young University Provo Utah 84602 USA
| | - David M. Eissenstat
- Department of Ecosystem Science and Management The Pennsylvania State University University Park Pennsylvania 16802 USA
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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. New Phytol 2016; 211:1159-69. [PMID: 27174359 DOI: 10.1111/nph.14003] [Citation(s) in RCA: 218] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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31
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Ceccon C, Tagliavini M, Schmitt AO, Eissenstat DM. Untangling the effects of root age and tissue nitrogen on root respiration in Populus tremuloides at different nitrogen supply. Tree Physiol 2016; 36:618-27. [PMID: 27095257 PMCID: PMC4886293 DOI: 10.1093/treephys/tpw022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 02/28/2016] [Indexed: 05/29/2023]
Abstract
Root respiration is a major contributor to terrestrial carbon flux. Many studies have shown root respiration to increase with an increase in root tissue nitrogen (N) concentration across species and study sites. Studies have also shown that both root respiration and root N concentration typically decrease with root age. The effects of added N may directly increase respiration of existing roots or may affect respiration by shifting the age structure of a root population by stimulating growth. To the best of our knowledge, no study has ever examined the effect of added N as a function of root age on root respiration. In this study, root respiration of 13-year-old Populus tremuloides Michx. trees grown in the field and 1-year-old P. tremuloides seedlings grown in containers was analyzed for the relative influence of root age and root N concentration independent of root age on root respiration. Field roots were first tracked using root windows and then sampled at known age. Nitrogen was either applied or not to small patches beneath the windows. In a pot experiment, each plant was grown with its root system split between two separate pots and N was applied at three different levels, either at the same or at different rates between pots. Root N concentration ranged between 1.4 and 1.7% in the field experiment and 1.8 and 2.6% in the seedling experiment. We found that addition of N increased root N concentration of only older roots in the field but of roots of all ages in the potted seedlings. In both experiments, the age-dependent decline in root respiration was largely consistent, and could be explained by a negative power function. Respiration decreased ∼50% by 3 weeks of age. Although root age was the dominant factor affecting respiration in both experiments, in the field experiment, root N also contributed to root respiration independent of root age. These results add further insight into respiratory responses of roots to N addition and mechanisms underlying the tissue N-respiration relationship.
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Affiliation(s)
- Christian Ceccon
- Faculty of Science and Technology, Free University of Bozen-Bolzano, University Square 5, 39100 Bolzano, Italy Department of Ecosystem Science and Management, Penn State University, 201 Forest Resources Bldg, University Park, PA 16802, USA
| | - Massimo Tagliavini
- Faculty of Science and Technology, Free University of Bozen-Bolzano, University Square 5, 39100 Bolzano, Italy
| | - Armin Otto Schmitt
- Faculty of Science and Technology, Free University of Bozen-Bolzano, University Square 5, 39100 Bolzano, Italy
| | - David M Eissenstat
- Department of Ecosystem Science and Management, Penn State University, 201 Forest Resources Bldg, University Park, PA 16802, USA
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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 Physiol 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Eissenstat DM, Kucharski JM, Zadworny M, Adams TS, Koide RT. Linking root traits to nutrient foraging in arbuscular mycorrhizal trees in a temperate forest. New Phytol 2015; 208:114-24. [PMID: 25970701 DOI: 10.1111/nph.13451] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 04/05/2015] [Indexed: 05/05/2023]
Affiliation(s)
- David M. Eissenstat
- Intercollege Graduate Degree Program in Plant Biology Penn State University University Park PA 16802 USA
- Department of Ecosystem Science and Management Penn State University University Park PA 16802 USA
| | - Joshua M. Kucharski
- Intercollege Graduate Degree Program in Plant Biology Penn State University University Park PA 16802 USA
| | - Marcin Zadworny
- Intercollege Graduate Degree Program in Plant Biology Penn State University University Park PA 16802 USA
- Institute of Dendrology Polish Academy of Sciences Parkowa 5 62‐035 Kórnik Poland
| | - Thomas S. Adams
- Department of Ecosystem Science and Management Penn State University University Park PA 16802 USA
| | - Roger T. Koide
- Intercollege Graduate Degree Program in Plant Biology Penn State University University Park PA 16802 USA
- Department of Biology Brigham Young University Provo UT 84602 USA
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Liu B, Li H, Zhu B, Koide RT, Eissenstat DM, Guo D. Complementarity in nutrient foraging strategies of absorptive fine roots and arbuscular mycorrhizal fungi across 14 coexisting subtropical tree species. New Phytol 2015; 208:125-36. [PMID: 25925733 DOI: 10.1111/nph.13434] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 03/29/2015] [Indexed: 05/05/2023]
Abstract
In most cases, both roots and mycorrhizal fungi are needed for plant nutrient foraging. Frequently, the colonization of roots by arbuscular mycorrhizal (AM) fungi seems to be greater in species with thick and sparsely branched roots than in species with thin and densely branched roots. Yet, whether a complementarity exists between roots and mycorrhizal fungi across these two types of root system remains unclear. We measured traits related to nutrient foraging (root morphology, architecture and proliferation, AM colonization and extramatrical hyphal length) across 14 coexisting AM subtropical tree species following root pruning and nutrient addition treatments. After root pruning, species with thinner roots showed more root growth, but lower mycorrhizal colonization, than species with thicker roots. Under multi-nutrient (NPK) addition, root growth increased, but mycorrhizal colonization decreased significantly, whereas no significant changes were found under nitrogen or phosphate additions. Moreover, root length proliferation was mainly achieved by altering root architecture, but not root morphology. Thin-root species seem to forage nutrients mainly via roots, whereas thick-root species rely more on mycorrhizal fungi. In addition, the reliance on mycorrhizal fungi was reduced by nutrient additions across all species. These findings highlight complementary strategies for nutrient foraging across coexisting species with contrasting root traits.
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Affiliation(s)
- Bitao Liu
- Center of Forest Ecosystem Studies and Qianyanzhou Ecological Station, Key Laboratory of Ecosystem Network Observation and Modeling, Synthesis Research Center of Chinese Ecosystem Research Network, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hongbo Li
- Center of Forest Ecosystem Studies and Qianyanzhou Ecological Station, Key Laboratory of Ecosystem Network Observation and Modeling, Synthesis Research Center of Chinese Ecosystem Research Network, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Biao Zhu
- Department of Ecology, College of Urban and Environmental Sciences, and Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, 100871, China
| | - Roger T Koide
- Department of Biology, Brigham Young University, Provo, UT, 84602, USA
| | - David M Eissenstat
- Department of Ecosystem Science and Management, and Intercollege Graduate Degree Program in Plant Biology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Dali Guo
- Center of Forest Ecosystem Studies and Qianyanzhou Ecological Station, Key Laboratory of Ecosystem Network Observation and Modeling, Synthesis Research Center of Chinese Ecosystem Research Network, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
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Makita N, Hirano Y, Sugimoto T, Tanikawa T, Ishii H. Intraspecific variation in fine root respiration and morphology in response to in situ soil nitrogen fertility in a 100-year-old Chamaecyparis obtusa forest. Oecologia 2015; 179:959-67. [DOI: 10.1007/s00442-015-3413-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 07/25/2015] [Indexed: 11/26/2022]
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McCormack ML, Lavely E, Ma Z. Fine-root and mycorrhizal traits help explain ecosystem processes and responses to global change. New Phytol 2014; 204:455-458. [PMID: 25312610 DOI: 10.1111/nph.13023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Affiliation(s)
- M Luke McCormack
- Key Laboratory of Ecosystem Network Observation and Modeling, Synthesis Research Center of Chinese Ecosystem Research Network, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Emily Lavely
- Department of Plant Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Zeqing Ma
- Key Laboratory of Ecosystem Network Observation and Modeling, Synthesis Research Center of Chinese Ecosystem Research Network, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
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Kong D, Ma C, Zhang Q, Li L, Chen X, Zeng H, Guo D. Leading dimensions in absorptive root trait variation across 96 subtropical forest species. New Phytol 2014; 203:863-72. [PMID: 24824672 DOI: 10.1111/nph.12842] [Citation(s) in RCA: 188] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 04/03/2014] [Indexed: 05/03/2023]
Abstract
Absorptive root traits show remarkable cross-species variation, but major root trait dimensions across species have not been defined. We sampled first-order roots and measured 14 root traits for 96 angiosperm woody species from subtropical China, including root diameter, specific root length, stele diameter, cortex thickness, root vessel size and density, mycorrhizal colonization rate, root branching intensity, tissue density, and concentrations of carbon and nitrogen ([N]). Root traits differed in the degree of variation and phylogenetic conservatism, but showed predictable patterns of cross-trait coordination. Root diameter, cortex thickness and stele diameter displayed high variation across species (coefficient of variation (CV)=0.51-0.69), whereas the stele:root diameter ratio and [N] showed low variation (CV<0.32). Root diameter, cortex thickness and stele diameter showed a strong phylogenetic signal across species, whereas root branching traits did not, and these two sets of traits were segregated onto two nearly orthogonal (independent) principal component analysis (PCA) axes. Two major dimensions of root trait variation were found: a diameter-related dimension potentially integrating root construction, maintenance, and persistence with mycorrhizal colonization, and a branching architecture dimension expressing root plastic responses to the environment. These two dimensions may offer a promising path for better understanding root trait economics and root ecological strategies world-wide.
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Affiliation(s)
- Deliang Kong
- The Key Laboratory for Urban Habitat Environmental Science and Technology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
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Abstract
The lifespan of fast-cycling roots is a critical parameter determining a large flux of plant carbon into soil through root turnover and is a biological feature regulating the capacity of a plant to capture soil water and nutrients via root-age-related physiological processes. While the importance of root lifespan to whole-plant and ecosystem processes is increasingly recognized, robust descriptions of this dynamic process and its response to changes in climatic and edaphic factors are lacking. Here we synthesize available information and propose testable hypotheses using conceptual models to describe how changes in temperature, water, nitrogen (N), and phosphorus (P) availability impact fine root lifespan within a species. Each model is based on intrinsic responses including root physiological activity and alteration of carbohydrate allocation at the whole-plant level as well as extrinsic factors including mycorrhizal fungi and pressure from pathogens, herbivores, and other microbes. Simplifying interactions among these factors, we propose three general principles describing fine root responses to complex environmental gradients. First, increases in a factor that strongly constrains plant growth (temperature, water, N, or P) should result in increased fine root lifespan. Second, increases in a factor that exceeds plant demand or tolerance should result in decreased lifespan. Third, as multiple factors interact fine root responses should be determined by the most dominant factor controlling plant growth. Moving forward, field experiments should determine which types of species (e.g., coarse vs. fine rooted, obligate vs. facultative mycotrophs) will express greater plasticity in response to environmental gradients while ecosystem models may begin to incorporate more detailed descriptions of root lifespan and turnover. Together these efforts will improve quantitative understanding of root dynamics and help to identify areas where future research should be focused.
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Affiliation(s)
- M. Luke McCormack
- Key Laboratory of Ecosystem Network Observation and Modeling, Synthesis Research Center of Chinese Ecosystem Research Network, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of SciencesBeijing, China
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Hu F, Mou PP, Weiner J, Li S. Contrasts between whole-plant and local nutrient levels determine root growth and death in Ailanthus altissima (Simaroubaceae). Am J Bot 2014; 101:812-819. [PMID: 24812109 DOI: 10.3732/ajb.1400129] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Accepted: 03/31/2014] [Indexed: 06/03/2023]
Abstract
UNLABELLED • PREMISE OF THE STUDY There is an ongoing debate about the importance of whole-plant control vs. local modular mechanisms for root growth. We conducted a split-root experiment with different patch/background levels of nitrogen to examine whether local root growth and death are controlled by local resource levels or at the whole-plant level.• METHODS Three microrhizotrons with 0, 10, and 100 µg N/g growth medium levels (74 g growth medium each) were attached to pots of high or low soil N in which one Ailanthus altissima individual was growing. One fine root was guided into each of the microrhizotrons and photographed every 4 d. Plants were harvested after 28 d; root growth and mortality in the microrhizotrons were recorded. Changes in root length, number of laterals, and interlateral length were determined from the photos and analyzed.• KEY RESULTS While overall plant growth was influenced by background N level, both patch and background N levels influenced root growth and mortality in patches. Local roots proliferated most when the patch N level was high and background level low, and they proliferated least and showed highest mortality when patch N was low and the background level high.• CONCLUSIONS The fate of roots growing in a patch is influenced by the resource environment of the plant's other roots as well as the resource levels in the patch itself. Thus, the growth and death of roots in patches is determined by both modular and whole-plant mechanisms.
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Affiliation(s)
- Fengqin Hu
- The Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, No. 19 Xinjiekouwai Street, Beijing 100875, China Institute of Soil Science, Chinese Academy of Sciences, No. 71 Beijing East Road, Nanjing 210008, China
| | - Paul P Mou
- The Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, No. 19 Xinjiekouwai Street, Beijing 100875, China
| | - Jacob Weiner
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg, Denmark
| | - Shuo Li
- The Ministry of Education Key Laboratory for Biodiversity Sciences and Ecological Engineering, College of Life Sciences, Beijing Normal University, No. 19 Xinjiekouwai Street, Beijing 100875, China
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