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Yuan J, Peng M, Tang G, Wang Y. Fine root production, mortality, and turnover in response to simulated nitrogen deposition in the subtropical Abies georgei (Orr) forest. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 923:171404. [PMID: 38432381 DOI: 10.1016/j.scitotenv.2024.171404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 02/28/2024] [Accepted: 02/29/2024] [Indexed: 03/05/2024]
Abstract
Increased nitrogen deposition has important effects on below-ground ecological processes. Fine roots are the most active part of the root system in terms of physiological activity and the main organs for nutrient and water uptake by plants. However, there is still a limited understanding of how nitrogen deposition affects the fine root dynamics in subtropical Abies georgei (Orr) forests. Consequently, a three-year field experiment was conducted to quantify the effects of three forms of nitrogen sources ((NH4)2SO4, NaNO3, and NH4NO3) at four levels (0, 5, 15, and 30 kg N·ha-1·yr-1) on the fine root dynamics in Abies georgei forests using a randomized block-group experimental design and minirhizotron technique. The first year of nitrogen addition did not affect the first-class fine roots (FR1, 0 < diameter < 0.5 mm) and second-class fine roots (FR2, 0.5 < diameter < 1.0 mm). The next two years of nitrogen addition significantly increased the production, mortality, and turnover of FR1 and FR2; the three year of nitrogen addition did not affect the dynamics of the third- class fine roots (FR3, 1.0 < diameter < 1.5 mm) and fourth- class fine roots (FR4,1.5 < diameter < 2.0 mm). Nitrogen addition positively affected the dynamics of FR1, FR2, FR3 and FR4 by positively affecting the carbon, nitrogen, and phosphorus contents of fine roots and indirectly affecting the soil pH. Increased carbon allocation to FR1 and FR2 may represent a phosphorus acquisition strategy when nitrogen is not the limiting factor. The nitrogen addition forms and levels affected the fine root dynamics in the following orde: NH4NO3 > (NH4)2SO4 > NaNO3 and high nitrogen > medium nitrogen > low nitrogen. The results suggest that the different-diameter fine root dynamics respond differently to different nitrogen addition forms and levels, and linking the different-diameter fine roots to nitrogen deposition is crucial.
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Affiliation(s)
- Jiyou Yuan
- School of Ecology and Environmental Sciences & Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, Yunnan University, Kunming, Yunnan 650091, China.
| | - Mingchun Peng
- School of Ecology and Environmental Sciences & Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, Yunnan University, Kunming, Yunnan 650091, China.
| | - Guoyong Tang
- Institute of Highland Forest Science, Chinese Academy of Forestry, Kunming 650233, China.
| | - Yun Wang
- Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection, College of Resources and Environment, Linyi University, Linyi 276000, China.
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Keller AB, Walter CA, Blumenthal DM, Borer ET, Collins SL, DeLancey LC, Fay PA, Hofmockel KS, Knops JMH, Leakey ADB, Mayes MA, Seabloom EW, Hobbie SE. Stronger fertilization effects on aboveground versus belowground plant properties across nine U.S. grasslands. Ecology 2023; 104:e3891. [PMID: 36208208 PMCID: PMC10078332 DOI: 10.1002/ecy.3891] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/09/2022] [Indexed: 02/03/2023]
Abstract
Increased nutrient inputs due to anthropogenic activity are expected to increase primary productivity across terrestrial ecosystems, but changes in allocation aboveground versus belowground with nutrient addition have different implications for soil carbon (C) storage. Thus, given that roots are major contributors to soil C storage, understanding belowground net primary productivity (BNPP) and biomass responses to changes in nutrient availability is essential to predicting carbon-climate feedbacks in the context of interacting global environmental changes. To address this knowledge gap, we tested whether a decade of nitrogen (N) and phosphorus (P) fertilization consistently influenced aboveground and belowground biomass and productivity at nine grassland sites spanning a wide range of climatic and edaphic conditions in the continental United States. Fertilization effects were strong aboveground, with both N and P addition stimulating aboveground biomass at nearly all sites (by 30% and 36%, respectively, on average). P addition consistently increased root production (by 15% on average), whereas other belowground responses to fertilization were more variable, ranging from positive to negative across sites. Site-specific responses to P were not predicted by the measured covariates. Atmospheric N deposition mediated the effect of N fertilization on root biomass and turnover. Specifically, atmospheric N deposition was positively correlated with root turnover rates, and this relationship was amplified with N addition. Nitrogen addition increased root biomass at sites with low N deposition but decreased it at sites with high N deposition. Overall, these results suggest that the effects of nutrient supply on belowground plant properties are context dependent, particularly with regard to background N supply rates, demonstrating that site conditions must be considered when predicting how grassland ecosystems will respond to increased nutrient loading from anthropogenic activity.
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Affiliation(s)
- Adrienne B. Keller
- Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSaint PaulMinnesotaUSA
| | | | - Dana M. Blumenthal
- USDA‐ARS Rangeland Resources & Systems Research UnitFort CollinsColoradoUSA
| | - Elizabeth T. Borer
- Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSaint PaulMinnesotaUSA
| | - Scott L. Collins
- Department of BiologyUniversity of New MexicoAlbuquerqueNew MexicoUSA
| | - Lang C. DeLancey
- Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSaint PaulMinnesotaUSA
| | - Philip A. Fay
- USDA‐ARS GrasslandSoil, and Water Research LaboratoryTempleTexasUSA
| | - Kirsten S. Hofmockel
- Earth and Biological Sciences DirectoratePacific Northwest National LaboratoryRichlandWashingtonUSA
- Department of AgronomyIowa State UniversityAmesIowaUSA
| | - Johannes M. H. Knops
- Health & Environmental Sciences DepartmentXi'an Jiaotong‐Liverpool UniversitySuzhouJiangsuChina
| | - Andrew D. B. Leakey
- Department of Plant Biology, Department of Crop SciencesUniversity of Illinois at Urbana‐ChampaignUrbana‐ChampaignIllinoisUSA
| | - Melanie A. Mayes
- Department of Earth and Planetary SciencesUniversity of TennesseeKnoxvilleTennesseeUSA
- Environmental Sciences DivisionOak Ridge National LaboratoryOak RidgeTennesseeUSA
| | - Eric W. Seabloom
- Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSaint PaulMinnesotaUSA
| | - Sarah E. Hobbie
- Department of Ecology, Evolution, and BehaviorUniversity of MinnesotaSaint PaulMinnesotaUSA
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Effects of Plant Fine Root Functional Traits and Soil Nutrients on the Diversity of Rhizosphere Microbial Communities in Tropical Cloud Forests in a Dry Season. FORESTS 2022. [DOI: 10.3390/f13030421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The composition and diversity of rhizosphere microbial communities may be due to root–soil–microbial interactions. The fine root functional traits and rhizosphere soil environmental factors of 13 representative plants in the Bawangling tropical cloud forest of Hainan Island were measured, to assess the key factors driving plant rhizosphere microbial communities. Illumina MiSeq sequencing technology was used to sequence the v3-V4 region of the 16SrDNA gene of 13 plant rhizosphere soil bacteria and the ITS1 region of the fungal ITSrDNA gene. Results showed that there were 355 families, 638 genera, and 719 species of rhizosphere soil bacteria as well as 29 families, 31 genera, and 31 species of rhizosphere soil fungi in the tropical cloud forests. The fine root traits, such as root phosphorus content, the specific root length and specific root area, were significantly negatively correlated with the Faith-pd indices of the bacterial community but were not correlated with the diversity of fungi communities. The soil pH was significantly and positively correlated with the Chao1 index, OTUs, Faith-pd and Simpson indices of the bacteria and fungi communities. The soil available phosphorus content was significantly and negatively correlated with the bacteria Simpson and the fungus Faith-pd indices. ABT analysis showed that soil pH and soil available phosphorus were the most important environmental conditions contributing to the rhizosphere bacterial and fungi communities, respectively. Our findings demonstrate that the soil environments had more influence on rhizosphere soil microbial diversity than the fine root functional traits.
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A Bibliometric Analysis of Global Fine Roots Research in Forest Ecosystems during 1992–2020. FORESTS 2022. [DOI: 10.3390/f13010093] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
(1) Background: Fine roots (≤2 mm in diameter) play a critical role in forest ecosystem ecological processes and has been widely identified as a major research topic. This study aimed to synthesize the global literature based on the Web of Science Core Collection scientific database from 1992 to 2020 and summarize the research trends and prospects on research of fine roots in forest ecosystems. A quantitative bibliometric analysis was presented with information related to authors, countries, institutions, journals, top cited publications, research hotspots, trends, and prospects. (2) Results: The results showed that the amount of publications has increased exponentially. USA, China, and Germany were the most productive countries. Chinese Academy of Science was the most productive institution on fine roots research and also has a key position in both domestic and international cooperation networks. Leuschner C and Hertel D were the most productive authors. Six core journals were confirmed from 471 journals based on Bradford’s law. The distribution of the frequency of authors and the number of their publications were fitted with Lotka’s Law. Author collaboration network was mainly limited in the same countries/territories and institutions. Keywords analysis indicates that the hotspots are biomass, decomposition, and respiration of fine roots, especially under climate change. (3) Conclusion: Our results provide a better understanding of global characteristics and trends of fine roots that have emerged in this field, which could offer reference for future research.
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Ji L, Liu Y, Wang J, Lu Z, Zhang L, Yang Y. Differential Variation in Non-structural Carbohydrates in Root Branch Orders of Fraxinus mandshurica Rupr. Seedlings Across Different Drought Intensities and Soil Substrates. FRONTIERS IN PLANT SCIENCE 2021; 12:692715. [PMID: 34956247 PMCID: PMC8692739 DOI: 10.3389/fpls.2021.692715] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 10/26/2021] [Indexed: 05/02/2023]
Abstract
Non-structural carbohydrates (NSCs) facilitate plant adaptation to drought stress, characterize tree growth and survival ability, and buffer against external disturbances. Previous studies have focused on the distribution and dynamics of NSCs among different plant organs under drought conditions. However, discussion about the NSC levels of fine roots in different root branch orders is limited, especially the relationship between fine root trait variation and NSC content. The objective of the study was to shed light on the synergistic variation in fine root traits and NSC content in different root branch orders under different drought and soil substrate conditions. The 2-year-old Fraxinus mandshurica Rupr. potted seedlings were planted in three different soil substrates (humus, loam, and sandy-loam soil) and subjected to four drought intensities (CK, mild drought, moderate drought, and severe drought) for 2 months. With increasing drought intensity, the biomass of fine roots decreased significantly. Under the same drought intensity, seedlings in sandy-loam soil had higher root biomass, and the coefficient of variation of 5th-order roots (37.4, 44.5, and 53% in humus, loam, and sandy-loam soil, respectively) was higher than that of lower-order roots. All branch order roots of seedlings in humus soil had the largest specific root length (SRL) and specific root surface area (SRA), in addition to the lowest diameter. With increasing drought intensity, the SRL and average diameter (AD) of all root branch orders increased and decreased, respectively. The fine roots in humus soil had a higher soluble sugar (SS) content and lower starch (ST) content compared to the loam and sandy-loam soil. Additionally, the SS and ST contents of fine roots showed decreasing and increasing tendencies with increasing drought intensities, respectively. SS and ST explained the highest degree of the total variation in fine root traits, which were 32 and 32.1%, respectively. With increasing root order, the explanation of the variation in root traits by ST decreased (only 6.8% for 5th-order roots). The observed response in terms of morphological traits of different fine root branch orders of F. mandshurica seedlings to resource fluctuations ensures the maintenance of a low cost-benefit ratio in the root system development.
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Affiliation(s)
- Li Ji
- Jilin Academy of Forestry, Changchun, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, China
| | - Yue Liu
- Jilin Academy of Forestry, Changchun, China
- Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, China
| | - Jun Wang
- Jilin Academy of Forestry, Changchun, China
| | - Zhimin Lu
- Jilin Academy of Forestry, Changchun, China
| | - Lijie Zhang
- School of Forestry, Shenyang Agricultural University, Shenyang, China
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Canadell JG, Meyer CP(M, Cook GD, Dowdy A, Briggs PR, Knauer J, Pepler A, Haverd V. Multi-decadal increase of forest burned area in Australia is linked to climate change. Nat Commun 2021; 12:6921. [PMID: 34836974 PMCID: PMC8626427 DOI: 10.1038/s41467-021-27225-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 11/03/2021] [Indexed: 12/05/2022] Open
Abstract
Fire activity in Australia is strongly affected by high inter-annual climate variability and extremes. Through changes in the climate, anthropogenic climate change has the potential to alter fire dynamics. Here we compile satellite (19 and 32 years) and ground-based (90 years) burned area datasets, climate and weather observations, and simulated fuel loads for Australian forests. Burned area in Australia's forests shows a linear positive annual trend but an exponential increase during autumn and winter. The mean number of years since the last fire has decreased consecutively in each of the past four decades, while the frequency of forest megafire years (>1 Mha burned) has markedly increased since 2000. The increase in forest burned area is consistent with increasingly more dangerous fire weather conditions, increased risk factors associated with pyroconvection, including fire-generated thunderstorms, and increased ignitions from dry lightning, all associated to varying degrees with anthropogenic climate change.
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Affiliation(s)
- Josep G. Canadell
- grid.492990.f0000 0004 0402 7163Climate Science Centre, CSIRO Oceans and Atmosphere, Canberra, ACT 2601 Australia
| | - C. P. (Mick) Meyer
- grid.492990.f0000 0004 0402 7163Climate Science Centre, CSIRO Oceans and Atmosphere, Aspendale, VIC 3195 Australia
| | - Garry D. Cook
- grid.469914.70000 0004 0385 5215CSIRO Land and Water, CSIRO Land and Water, PMB 44, Winnellie, NT 0822 Australia
| | - Andrew Dowdy
- grid.1527.1000000011086859XBureau of Meteorology, Climate Research Section, Bureau of Meteorology, Melbourne, VIC Australia
| | - Peter R. Briggs
- grid.492990.f0000 0004 0402 7163Climate Science Centre, CSIRO Oceans and Atmosphere, Canberra, ACT 2601 Australia
| | - Jürgen Knauer
- grid.492990.f0000 0004 0402 7163Climate Science Centre, CSIRO Oceans and Atmosphere, Canberra, ACT 2601 Australia
| | - Acacia Pepler
- grid.1527.1000000011086859XBureau of Meteorology, Climate Research Section, Bureau of Meteorology, Melbourne, VIC Australia
| | - Vanessa Haverd
- grid.492990.f0000 0004 0402 7163Climate Science Centre, CSIRO Oceans and Atmosphere, Canberra, ACT 2601 Australia
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7
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Huaraca Huasco W, Riutta T, Girardin CAJ, Hancco Pacha F, Puma Vilca BL, Moore S, Rifai SW, Del Aguila-Pasquel J, Araujo Murakami A, Freitag R, Morel AC, Demissie S, Doughty CE, Oliveras I, Galiano Cabrera DF, Durand Baca L, Farfán Amézquita F, Silva Espejo JE, da Costa ACL, Oblitas Mendoza E, Quesada CA, Evouna Ondo F, Edzang Ndong J, Jeffery KJ, Mihindou V, White LJT, N'ssi Bengone N, Ibrahim F, Addo-Danso SD, Duah-Gyamfi A, Djaney Djagbletey G, Owusu-Afriyie K, Amissah L, Mbou AT, Marthews TR, Metcalfe DB, Aragão LEO, Marimon-Junior BH, Marimon BS, Majalap N, Adu-Bredu S, Abernethy KA, Silman M, Ewers RM, Meir P, Malhi Y. Fine root dynamics across pantropical rainforest ecosystems. GLOBAL CHANGE BIOLOGY 2021; 27:3657-3680. [PMID: 33982340 DOI: 10.1111/gcb.15677] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 02/27/2021] [Accepted: 03/12/2021] [Indexed: 06/12/2023]
Abstract
Fine roots constitute a significant component of the net primary productivity (NPP) of forest ecosystems but are much less studied than aboveground NPP. Comparisons across sites and regions are also hampered by inconsistent methodologies, especially in tropical areas. Here, we present a novel dataset of fine root biomass, productivity, residence time, and allocation in tropical old-growth rainforest sites worldwide, measured using consistent methods, and examine how these variables are related to consistently determined soil and climatic characteristics. Our pantropical dataset spans intensive monitoring plots in lowland (wet, semi-deciduous, and deciduous) and montane tropical forests in South America, Africa, and Southeast Asia (n = 47). Large spatial variation in fine root dynamics was observed across montane and lowland forest types. In lowland forests, we found a strong positive linear relationship between fine root productivity and sand content, this relationship was even stronger when we considered the fractional allocation of total NPP to fine roots, demonstrating that understanding allocation adds explanatory power to understanding fine root productivity and total NPP. Fine root residence time was a function of multiple factors: soil sand content, soil pH, and maximum water deficit, with longest residence times in acidic, sandy, and water-stressed soils. In tropical montane forests, on the other hand, a different set of relationships prevailed, highlighting the very different nature of montane and lowland forest biomes. Root productivity was a strong positive linear function of mean annual temperature, root residence time was a strong positive function of soil nitrogen content in montane forests, and lastly decreasing soil P content increased allocation of productivity to fine roots. In contrast to the lowlands, environmental conditions were a better predictor for fine root productivity than for fractional allocation of total NPP to fine roots, suggesting that root productivity is a particularly strong driver of NPP allocation in tropical mountain regions.
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Affiliation(s)
- Walter Huaraca Huasco
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Terhi Riutta
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Cécile A J Girardin
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | | | | | - Sam Moore
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Sami W Rifai
- ARC Centre of Excellence for Climate Extremes, University of New South Wales, Sydney, NSW, Australia
| | | | - Alejandro Araujo Murakami
- Museo de Historia Natural Noel Kempff Mercado Universidad Autónoma Gabriel Rene Moreno, Santa Cruz, Bolivia
| | - Renata Freitag
- Programa de Pós-graduação em Ecologia e Conservação, Universidade do Estado de Mato Grosso, Nova Xavantina, MT, Brazil
| | - Alexandra C Morel
- Department of Geography and Environmental Science, University of Dundee, Dundee, UK
| | | | - Christopher E Doughty
- School of Informatics, Computing and Cyber systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Imma Oliveras
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
| | | | | | | | | | | | | | | | | | | | | | - Vianet Mihindou
- Ministère de la Foret, de la Mer, de l'Environnement, Chargé Du Plan Climat, Libreville, Gabon
| | - Lee J T White
- Ministère de la Foret, de la Mer, de l'Environnement, Chargé Du Plan Climat, Libreville, Gabon
| | - Natacha N'ssi Bengone
- Ministère de la Foret, de la Mer, de l'Environnement, Chargé Du Plan Climat, Libreville, Gabon
| | - Forzia Ibrahim
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, University, Kumasi, Ghana
| | - Shalom D Addo-Danso
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, University, Kumasi, Ghana
| | - Akwasi Duah-Gyamfi
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, University, Kumasi, Ghana
| | - Gloria Djaney Djagbletey
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, University, Kumasi, Ghana
| | - Kennedy Owusu-Afriyie
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, University, Kumasi, Ghana
| | - Lucy Amissah
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, University, Kumasi, Ghana
| | - Armel T Mbou
- Centro Euro-Mediterraneo sui Cambiamenti Climatici, Leece, Italy
| | | | - Daniel B Metcalfe
- Department of Ecology and Environment Science, Umeå University, Umeå, Sweden
| | - Luiz E O Aragão
- Divisão de Sensoriamento Remoto-DIDSR, Instituto Nacional de Pesquisas Espaciais, São Jose dos Campos, SP, Brazil
| | - Ben H Marimon-Junior
- Programa de Pós-graduação em Ecologia e Conservação, Universidade do Estado de Mato Grosso, Nova Xavantina, MT, Brazil
| | - Beatriz S Marimon
- Programa de Pós-graduação em Ecologia e Conservação, Universidade do Estado de Mato Grosso, Nova Xavantina, MT, Brazil
| | - Noreen Majalap
- Sabah Forestry Department, Forest Research Centre, Sabah, Malaysia
| | - Stephen Adu-Bredu
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, University, Kumasi, Ghana
| | | | - Miles Silman
- Department of Biology, Wake Forest University, Winston-Salem, NC, USA
| | - Robert M Ewers
- Department of Life Science, Imperial College London, Ascot, UK
| | - Patrick Meir
- Research School of Biology, Australian National University, Canberra, ACT, Australia
- School of Geosciences, University of Edinburgh, Edinburgh, UK
| | - Yadvinder Malhi
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
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徐 丽. Research Progress on Effects of Nitrogen Deposition on Dynamics and Morphology of Forest Fine Roots. INTERNATIONAL JOURNAL OF ECOLOGY 2021. [DOI: 10.12677/ije.2021.104078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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董 宁. Research Progress of Forest Fine Root Dynamics and Morphology Respond to Increased Nitrogen Availability. INTERNATIONAL JOURNAL OF ECOLOGY 2021. [DOI: 10.12677/ije.2021.101010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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10
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孙 贺. Simulated Effects of Atmospheric Nitrogen Deposition on the Morphology and Anatomical Structure of Fine Roots: A Review. INTERNATIONAL JOURNAL OF ECOLOGY 2021. [DOI: 10.12677/ije.2021.102021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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11
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梁 璐. The Effects of Nitrogen Deposition on Fine Root Longevity in Forest Ecosystem: A Review. INTERNATIONAL JOURNAL OF ECOLOGY 2021. [DOI: 10.12677/ije.2021.101002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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12
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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] [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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13
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Fornara DA, Flynn D, Caruso T. Effects of nutrient fertilization on root decomposition and carbon accumulation in intensively managed grassland soils. Ecosphere 2020. [DOI: 10.1002/ecs2.3103] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
| | - David Flynn
- Agri‐Food and Biosciences Institute (AFBI) BelfastBT9 5PXUK
| | - Tancredi Caruso
- School of Biology and Environmental Science, University College Dublin Dublin Ireland
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14
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Galdos MV, Brown E, Rosolem CA, Pires LF, Hallett PD, Mooney SJ. Brachiaria species influence nitrate transport in soil by modifying soil structure with their root system. Sci Rep 2020; 10:5072. [PMID: 32193510 PMCID: PMC7081357 DOI: 10.1038/s41598-020-61986-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 03/05/2020] [Indexed: 11/15/2022] Open
Abstract
Leaching of nitrate from fertilisers diminishes nitrogen use efficiency (the portion of nitrogen used by a plant) and is a major source of agricultural pollution. To improve nitrogen capture, grasses such as brachiaria are increasingly used, especially in South America and Africa, as a cover crop, either via intercropping or in rotation. However, the complex interactions between soil structure, nitrogen and the root systems of maize and different species of forage grasses remain poorly understood. This study explored how soil structure modification by the roots of maize (Zea maize), palisade grass (Brachiaria brizantha cv. Marandu) and ruzigrass (Brachiaria ruziziensis) affected nitrate leaching and retention, measured via chemical breakthrough curves. All plants were found to increase the rate of nitrate transport suggesting root systems increase the tendency for preferential flow. The greater density of fine roots produced by palisade grass, subtly decreased nitrate leaching potential through increased complexity of the soil pore network assessed with X-ray Computed Tomography. A dominance of larger roots in ruzigrass and maize increased nitrate loss through enhanced solute flow bypassing the soil matrix. These results suggest palisade grass could be a more efficient nitrate catch crop than ruzigrass (the most extensively used currently in countries such as Brazil) due to retardation in solute flow associated with the fine root system and the complex pore network.
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Affiliation(s)
- M V Galdos
- Institute for Climate and Atmospheric Science, School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, UK.,Division of Agricultural & Environmental Science, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Sutton Bonington, Loughborough, LE12 5RD, UK
| | - E Brown
- Division of Agricultural & Environmental Science, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Sutton Bonington, Loughborough, LE12 5RD, UK
| | - C A Rosolem
- Department of Crop Science, São Paulo State University, Botucatu, Brazil
| | - L F Pires
- Department of Physics, State University of Ponta Grossa, Ponta Grossa, Brazil
| | - P D Hallett
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | - S J Mooney
- Division of Agricultural & Environmental Science, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Sutton Bonington, Loughborough, LE12 5RD, UK.
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15
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Neumann M, Godbold DL, Hirano Y, Finér L. Improving models of fine root carbon stocks and fluxes in European forests. THE JOURNAL OF ECOLOGY 2020; 108:496-514. [PMID: 32189723 PMCID: PMC7065197 DOI: 10.1111/1365-2745.13328] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 11/11/2019] [Indexed: 06/10/2023]
Abstract
Fine roots and above-ground litterfall play a pivotal role in carbon dynamics in forests. Nonetheless, direct estimation of stocks of fine roots remains methodologically challenging. Models are thus widely used to estimate these stocks and help elucidate drivers of fine root growth and turnover, at a range of scales.We updated a database of fine root biomass, necromass and production derived from 454 plots across European forests. We then compared fine root biomass and production to estimates obtained from 19 different models. Typical input variables used for the models included climate, net primary production, foliage and above-ground biomass, leaf area index (LAI), latitude and/or land cover type. We tested whether performance could be improved by fitting new multiple regression models, and explored effects of species composition and sampling method on estimated fine root biomass.Average fine root biomass was 332 g/m2, and necromass 379 g/m2, for European forests where the average fine root production was 250 g m-2 year-1. Carbon fraction in fine roots averaged 48.4%, and was 1.5% greater in broadleaved species than conifers.Available models were poor predictors of fine root biomass and production. The best performing models assumed proportionality between above- and below-ground compartments, and used remotely sensed LAI or foliage biomass as key inputs. Model performance was improved by use of multiple regressions, which revealed consistently greater biomass and production in stands dominated by broadleaved species as well as in mixed stands even after accounting for climatic differences. Synthesis. We assessed the potential of existing models to estimate fine root biomass and production in European forests. We show that recalibration reduces by about 40% errors in estimates currently produced by the best available models, and increases three-fold explained variation. Our results underline the quantitative significance of fine roots (live and dead) to the global carbon cycle.
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Affiliation(s)
- Mathias Neumann
- Institute of SilvicultureUniversity of Natural Resources and Life SciencesViennaAustria
| | - Douglas L. Godbold
- Institute of Forest EcologyUniversity of Natural Resources and Life SciencesViennaAustria
- Global Change Research CentreAcademy of Sciences of the Czech RepublicPragueCzech Republic
| | - Yasuhiro Hirano
- Graduate School of Environmental StudiesNagoya UniversityNagoyaJapan
| | - Leena Finér
- Natural Resources Institute FinlandJoensuuFinland
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16
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Piñeiro J, Ochoa-Hueso R, Delgado-Baquerizo M, Dobrick S, Reich PB, Pendall E, Power SA. Effects of elevated CO 2 on fine root biomass are reduced by aridity but enhanced by soil nitrogen: A global assessment. Sci Rep 2017; 7:15355. [PMID: 29127358 PMCID: PMC5681551 DOI: 10.1038/s41598-017-15728-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 10/31/2017] [Indexed: 11/08/2022] Open
Abstract
Plant roots play a crucial role in regulating key ecosystem processes such as carbon (C) sequestration and nutrient solubilisation. Elevated (e)CO2 is expected to alter the biomass of fine, coarse and total roots to meet increased demand for other resources such as water and nitrogen (N), however, the magnitude and direction of observed changes vary considerably between ecosystems. Here, we assessed how climate and soil properties mediate root responses to eCO2 by comparing 24 field-based CO2 experiments across the globe including a wide range of ecosystem types. We calculated response ratios (i.e. effect size) and used structural equation modelling (SEM) to achieve a system-level understanding of how aridity, mean annual temperature and total soil nitrogen simultaneously drive the response of total, coarse and fine root biomass to eCO2. Models indicated that increasing aridity limits the positive response of fine and total root biomass to eCO2, and that fine (but not coarse or total) root responses to eCO2 are positively related to soil total N. Our results provide evidence that consideration of factors such as aridity and soil N status is crucial for predicting plant and ecosystem-scale responses to future changes in atmospheric CO2 concentrations, and thus feedbacks to climate change.
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Affiliation(s)
- Juan Piñeiro
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia.
| | - Raúl Ochoa-Hueso
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia
| | - Manuel Delgado-Baquerizo
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia
| | - Silvan Dobrick
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia
| | - Peter B Reich
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia
- Department of Forest Resources, University of Minnesota, St. Paul, Minnesota, USA
| | - Elise Pendall
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia
| | - Sally A Power
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia
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17
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Okada KI, Aiba SI, Kitayama K. Influence of temperature and soil nitrogen and phosphorus availabilities on fine-root productivity in tropical rainforests on Mount Kinabalu, Borneo. Ecol Res 2016. [DOI: 10.1007/s11284-016-1425-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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18
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Majdi H, Kangas P. Demography of fine roots in response to nutrient applications in a Norway spruce stand in southwestern Sweden. ECOSCIENCE 2016. [DOI: 10.1080/11956860.1997.11682396] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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19
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Hendrick RL, Pregitzer KS. The relationship between fine root demography and the soil environment in northern hardwood forests. ECOSCIENCE 2016. [DOI: 10.1080/11956860.1997.11682383] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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20
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Frank DA, Pontes AW, Maine EM, Fridley JD. Fine-scale belowground species associations in temperate grassland. Mol Ecol 2015; 24:3206-16. [PMID: 25951537 DOI: 10.1111/mec.13232] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 05/01/2015] [Accepted: 05/05/2015] [Indexed: 12/01/2022]
Abstract
Evaluating how belowground processes contribute to plant community dynamics is hampered by limited information on the spatial structure of root communities at the scale that plants interact belowground. In this study, roots were mapped to the nearest one mm and molecularly identified by species on vertical (0-15 cm deep) surfaces of soil blocks excavated from dry and mesic grasslands in Yellowstone National Park (YNP) to examine the spatial relationships among species at the scale that roots interact. Our results indicated that average interspecific root - root distances for the majority of species were within a distance (3 mm) that roots have been shown to compete for resources. Most species placed their roots at random, although low root numbers for many species probably led to overestimating the occurrence of random patterns. According to theory, we expected that most of the remaining species would segregate their root systems to avoid competition. Instead we found that more species aggregated than segregated from others. Based on previous investigations, we hypothesize that species aggregate to increase uptake of water, nitrogen and/or phosphorus made available by neighbouring roots, or as a consequence of a reduction in the pathogenicity of soil biota growing in multispecies mixtures. Our results indicate that YNP grassland root communities are organized as closely interdigitating networks of species that potentially can support strong interactions among many species combinations. Future root research should address the prevalence and functional consequences of species aggregation across plant communities.
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Affiliation(s)
- Douglas A Frank
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA
| | - Alyssa W Pontes
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA
| | - Eleanor M Maine
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA
| | - Jason D Fridley
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA
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21
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McCormack ML, Guo D. Impacts of environmental factors on fine root lifespan. FRONTIERS IN PLANT SCIENCE 2014; 5:205. [PMID: 24904605 PMCID: PMC4032987 DOI: 10.3389/fpls.2014.00205] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 04/28/2014] [Indexed: 05/17/2023]
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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22
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Rytter RM. The effect of limited availability of N or water on C allocation to fine roots and annual fine root turnover in Alnus incana and Salix viminalis. TREE PHYSIOLOGY 2013; 33:924-39. [PMID: 23963409 DOI: 10.1093/treephys/tpt060] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The effect of limited nitrogen (N) or water availability on fine root growth and turnover was examined in two deciduous species, Alnus incana L. and Salix viminalis L., grown under three different regimes: (i) supply of N and water in amounts which would not hamper growth, (ii) limited N supply and (iii) limited water supply. Plants were grown outdoors during three seasons in covered and buried lysimeters placed in a stand structure and filled with quartz sand. Computer-controlled irrigation and fertilization were supplied through drip tubes. Production and turnover of fine roots were estimated by combining minirhizotron observations and core sampling, or by sequential core sampling. Annual turnover rates of fine roots <1 mm (5-6 year(-1)) and 1-2 mm (0.9-2.8 year(-1)) were not affected by changes in N or water availability. Fine root production (<1 mm) differed between Alnus and Salix, and between treatments in Salix; i.e., absolute length and biomass production increased in the order: water limited < unlimited < N limited. Few treatment effects were detected for fine roots 1-2 mm. Proportionally more C was allocated to fine roots (≤2 mm) in N or water-limited Salix; 2.7 and 2.3 times the allocation to fine roots in the unlimited regime, respectively. Estimated input to soil organic carbon increased by ca. 20% at N limitation in Salix. However, future studies on fine root decomposition under various environmental conditions are required. Fine root growth responses to N or water limitation were less pronounced in Alnus, thus indicating species differences caused by N-fixing capacity and slower initial growth in Alnus, or higher fine root plasticity in Salix. A similar seasonal growth pattern across species and treatments suggested the influence of outer stimuli, such as temperature and light.
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Affiliation(s)
- Rose-Marie Rytter
- Swedish University of Agricultural Sciences, S-750 07 Uppsala, Sweden; Present address: Rytter Science, Backavägen 16, S-268 68 Röstånga, Sweden
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23
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Smithwick EAH, Eissenstat DM, Lovett GM, Bowden RD, Rustad LE, Driscoll CT. Root stress and nitrogen deposition: consequences and research priorities. THE NEW PHYTOLOGIST 2013; 197:712-9. [PMID: 23418632 DOI: 10.1111/nph.12081] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Stress within tree roots may influence whole-tree responses to nutrient deficiencies or toxic ion accumulation, but the mechanisms that govern root responses to the belowground chemical environment are poorly quantified. Currently, root production is modeled using rates of forest production and stoichiometry, but this approach alone may be insufficient to forecast variability in forest responses when physical and chemical stressors alter root lifespan, rooting depth or mycorrhizal colonization directly. Here, we review key research priorities for improving predictions of tree responses to changes in the belowground biogeochemical environment resulting from nitrogen deposition, including: limits of the optimum allocation paradigm, root physiological stress and lifespan, contingency effects that determine threshold responses across broad gradients, coupled water-biogeochemical interactions on roots, mycorrhizal dynamics that mediate root resilience and model frameworks to better simulate root feedbacks to aboveground function. We conclude that models incorporating physiological feedbacks, dynamic responses to coupled stressors, mycorrhizal interactions, and which challenge widely-accepted notions of optimum allocation, can elucidate potential thresholds of tree responses to biogeochemical stressors. Emphasis on comparative studies across species and environmental gradients, and which incorporates insights at the cellular and ecosystem level, is critical for forecasting whole-tree responses to altered biogeochemical landscapes.
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Affiliation(s)
- Erica A H Smithwick
- Department of Geography and Intercollege Graduate Degree Program in Ecology, The Pennsylvania State University, University Park, PA 16802, USA.
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24
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Yuan ZY, Chen HYH. A global analysis of fine root production as affected by soil nitrogen and phosphorus. Proc Biol Sci 2012; 279:3796-802. [PMID: 22764168 DOI: 10.1098/rspb.2012.0955] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Fine root production is the largest component of belowground production and plays substantial roles in the biogeochemical cycles of terrestrial ecosystems. The increasing availability of nitrogen (N) and phosphorus (P) due to human activities is expected to increase aboveground net primary production (ANNP), but the response of fine root production to N and P remains unclear. If roots respond to nutrients as ANNP, fine root production is anticipated to increase with increasing soil N and P. Here, by synthesizing data along the nutrient gradient from 410 natural habitats and from 469 N and/or P addition experiments, we showed that fine root production increased in terrestrial ecosystems with an average increase along the natural N gradient of up to 0.5 per cent with increasing soil N. Fine root production also increased with soil P in natural conditions, particularly at P < 300 mg kg(-1). With N, P and combined N + P addition, fine root production increased by a global average of 27, 21 and 40 per cent, respectively. However, its responses differed among ecosystems and soil types. The global average increases in fine root production are lower than those of ANNP, indicating that above- and belowground counterparts are coupled, but production allocation shifts more to aboveground with higher soil nutrients. Our results suggest that the increasing fertilizer use and combined N deposition at present and in the future will stimulate fine root production, together with ANPP, probably providing a significant influence on atmospheric CO(2) emissions.
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Affiliation(s)
- Z Y Yuan
- Faculty of Natural Resources Management, Lakehead University, Thunder Bay, Ontario, Canada P7B 5E1
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25
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Powers JS, Peréz-Aviles D. Edaphic Factors are a More Important Control on Surface Fine Roots than Stand Age in Secondary Tropical Dry Forests. Biotropica 2012. [DOI: 10.1111/j.1744-7429.2012.00881.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jennifer S. Powers
- Department of Ecology, Evolution and Behavior; University of Minnesota; 100 Ecology Building 1987 Upper Buford Circle St. Paul MN 55108 U.S.A
- Department of Plant Biology; University of Minnesota; St. Paul MN 55108 U.S.A
- Smithsonian Tropical Research Institute; Apartado Balboa 2072 Panama
| | - Daniel Peréz-Aviles
- Department of Ecology, Evolution and Behavior; University of Minnesota; 100 Ecology Building 1987 Upper Buford Circle St. Paul MN 55108 U.S.A
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26
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Affiliation(s)
- Eckhard George
- Institut für Pflanzenernährung, Universität Hohenheim, D‐70593 Stuttgart
| | - Horst Marschner
- Institut für Pflanzenernährung, Universität Hohenheim, D‐70593 Stuttgart
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27
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Rascher U, Blossfeld S, Fiorani F, Jahnke S, Jansen M, Kuhn AJ, Matsubara S, M Rtin LLA, Merchant A, Metzner R, M Ller-Linow M, Nagel KA, Pieruschka R, Pinto F, Schreiber CM, Temperton VM, Thorpe MR, Dusschoten DV, Van Volkenburgh E, Windt CW, Schurr U. Non-invasive approaches for phenotyping of enhanced performance traits in bean. FUNCTIONAL PLANT BIOLOGY : FPB 2011; 38:968-983. [PMID: 32480955 DOI: 10.1071/fp11164] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 10/15/2011] [Indexed: 05/26/2023]
Abstract
Plant phenotyping is an emerging discipline in plant biology. Quantitative measurements of functional and structural traits help to better understand gene-environment interactions and support breeding for improved resource use efficiency of important crops such as bean (Phaseolus vulgaris L.). Here we provide an overview of state-of-the-art phenotyping approaches addressing three aspects of resource use efficiency in plants: belowground roots, aboveground shoots and transport/allocation processes. We demonstrate the capacity of high-precision methods to measure plant function or structural traits non-invasively, stating examples wherever possible. Ideally, high-precision methods are complemented by fast and high-throughput technologies. High-throughput phenotyping can be applied in the laboratory using automated data acquisition, as well as in the field, where imaging spectroscopy opens a new path to understand plant function non-invasively. For example, we demonstrate how magnetic resonance imaging (MRI) can resolve root structure and separate root systems under resource competition, how automated fluorescence imaging (PAM fluorometry) in combination with automated shape detection allows for high-throughput screening of photosynthetic traits and how imaging spectrometers can be used to quantify pigment concentration, sun-induced fluorescence and potentially photosynthetic quantum yield. We propose that these phenotyping techniques, combined with mechanistic knowledge on plant structure-function relationships, will open new research directions in whole-plant ecophysiology and may assist breeding for varieties with enhanced resource use efficiency varieties.
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28
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Bai W, Xun F, Li Y, Zhang W, Li L. Rhizome severing increases root lifespan of Leymus chinensis in a typical steppe of Inner Mongolia. PLoS One 2010; 5:e12125. [PMID: 20711343 PMCID: PMC2920826 DOI: 10.1371/journal.pone.0012125] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Accepted: 07/16/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Root lifespan is an important trait that determines plants' ability to acquire and conserve soil resources. There have been several studies investigating characteristics of root lifespan of both woody and herbaceous species. However, most of the studies have focused on non-clonal plants, and there have been little data on root lifespan for clonal plants that occur widely in temperate grasslands. METHODOLOGY/PRINCIPAL FINDINGS We investigated the effects of rhizome severing on overall root lifespan of Leymus chinensis, a clonal, dominant grass species in the temperate steppe in northern China, in a 2-year field study using modified rhizotron technique. More specifically, we investigated the effects of rhizome severing on root lifespan of roots born in different seasons and distributed at different soil depths. Rhizome severing led to an increase in the overall root lifespan from 81 to 103 days. The increase in root lifespan exhibited spatial and temporal characteristics such that it increased lifespan for roots distributed in the top two soil layers and for roots born in summer and spring, but it had no effect on lifespan of roots in the deep soil layer and born in autumn. We also examined the effect of rhizome severing on carbohydrate and N contents in roots, and found that root carbohydrate and N contents were not affected by rhizome severing. Further, we found that root lifespan of Stipa krylovii and Artemisia frigida, two dominant, non-clonal species in the temperate steppe, was significantly longer (118 d) than that of L. chinensis (81 d), and this value became comparable to that of L. chinensis under rhizome severing (103 d). CONCLUSIONS/SIGNIFICANCE We found that root lifespan in dominant, clonal L. chinensis was shorter than for the dominant, non-clonal species of S. krylovii and A. frigida. There was a substantial increase in the root lifespan of L. chinensis in response to severing their rhizomes, and this increase in root lifespan exhibited temporal and spatial characteristics. These findings suggest that the presence of rhizomes is likely to account for the observed short lifespan of clonal plant species in the temperate steppe.
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Affiliation(s)
- Wenming Bai
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Fen Xun
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- Graduate School of Chinese Academy of Science, Yuquanlu, Beijing, China
| | - Yang Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- Graduate School of Chinese Academy of Science, Yuquanlu, Beijing, China
| | - Wenhao Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Linghao Li
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
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29
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Tateno R, Takeda H. Nitrogen uptake and nitrogen use efficiency above and below ground along a topographic gradient of soil nitrogen availability. Oecologia 2010; 163:793-804. [DOI: 10.1007/s00442-009-1561-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Accepted: 12/29/2009] [Indexed: 11/29/2022]
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30
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Milchunas DG. Estimating Root Production: Comparison of 11 Methods in Shortgrass Steppe and Review of Biases. Ecosystems 2009. [DOI: 10.1007/s10021-009-9295-8] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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Bader M, Hiltbrunner E, Körner C. Fine root responses of mature deciduous forest trees to free air carbon dioxide enrichment (FACE). Funct Ecol 2009. [DOI: 10.1111/j.1365-2435.2009.01574.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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32
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Bai WM, Wang ZW, Chen QS, Zhang WH, Li LH. Spatial and temporal effects of nitrogen addition on root life span ofLeymus chinensisin a typical steppe of Inner Mongolia. Funct Ecol 2008. [DOI: 10.1111/j.1365-2435.2008.01403.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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33
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Markham JH, Zekveld C. Nitrogen fixation makes biomass allocation to roots independent of soil nitrogen supply. ACTA ACUST UNITED AC 2007. [DOI: 10.1139/b07-075] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Biomass allocation patterns in plants are known to be affected by soil nitrogen availability. Since nitrogen availability can depress symbiotic nitrogen fixation, and nitrogen fixation can make plant growth independent of soil nitrogen availability but is energetically costly, it is unclear how allocation patterns in nitrogen-fixing species should respond to variation in soil nitrogen availability. We examined the effect of nitrogen source and concentration on the growth and allocation patterns in the nitrogen-fixing shrub Alnus viridis subsp. crispa (Aiton) Turrill. Plants were grown with either NH4+-N or NO3–-N at a range of low N concentrations, from 0 to 2 mmol·L–1, and either inoculated with Frankia or not. Plants without nodules had 25.l% lower biomass and had double the allocation to roots at all but the 2 mmol·L–1 nitrogen concentration. Even though nodulated plants increased growth with nitrogen concentration, allocation to roots as a fraction of total biomass did not vary in these plants, suggesting increased growth resulted from more efficient nitrogen acquisition. Allocation to roots was a significant predictor of plant growth in non-nodulated plants (r2 = 0.318, for linear least squares fit with log mass) but not for nodulated plants (r2 = 0.108). As nitrogen concentrations increased, allocation to nodules, specific nodule numbers, and the proportion of nitrogen fixed by the plants decreased, demonstrating a shift to soil nitrogen use.
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Affiliation(s)
- John H. Markham
- Botany Department, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Corinthe Zekveld
- Botany Department, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
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Uselman SM, Qualls RG, Lilienfein J. Fine Root Production across a Primary Successional Ecosystem Chronosequence at Mt. Shasta, California. Ecosystems 2007. [DOI: 10.1007/s10021-007-9045-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Fischer DG, Hart SC, Rehill BJ, Lindroth RL, Keim P, Whitham TG. Do high-tannin leaves require more roots? Oecologia 2006; 149:668-75. [PMID: 16804703 DOI: 10.1007/s00442-006-0471-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2006] [Accepted: 05/15/2006] [Indexed: 10/24/2022]
Abstract
The well-known deceleration of nitrogen (N) cycling in the soil resulting from addition of large amounts of foliar condensed tannins may require increased fine-root growth in order to meet plant demands for N. We examined correlations between fine-root production, plant genetics, and leaf secondary compounds in Populus angustifolia, P. fremontii, and their hybrids. We measured fine-root (<2 mm) production and leaf chemistry along an experimental genetic gradient where leaf litter tannin concentrations are genetically based and exert strong control on net N mineralization in the soil. Fine-root production was highly correlated with leaf tannins and individual tree genetic composition based upon genetic marker estimates, suggesting potential genetic control of compensatory root growth in response to accumulation of foliar secondary compounds in soils. We suggest, based on previous studies in our system and the current study, that genes for tannin production could link foliar chemistry and root growth, which may provide a powerful setting for external feedbacks between above- and belowground processes.
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Affiliation(s)
- D G Fischer
- School of Forestry, Northern Arizona University, Flagstaff, AZ 86011, USA.
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36
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Newman GS, Arthur MA, Muller RN. Above- and Belowground Net Primary Production in a Temperate Mixed Deciduous Forest. Ecosystems 2006. [DOI: 10.1007/s10021-006-0015-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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37
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Phillips DL, Johnson MG, Tingey DT, Storm MJ, Ball JT, Johnson DW. CO2 and N-fertilization effects on fine-root length, production, and mortality: a 4-year ponderosa pine study. Oecologia 2006; 148:517-25. [PMID: 16547735 DOI: 10.1007/s00442-006-0392-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2005] [Accepted: 02/21/2006] [Indexed: 11/26/2022]
Abstract
We conducted a 4-year study of juvenile Pinus ponderosa fine root (< or =2 mm) responses to atmospheric CO2 and N-fertilization. Seedlings were grown in open-top chambers at three CO2 levels (ambient, ambient+175 mumol/mol, ambient+350 mumol/mol) and three N-fertilization levels (0, 10, 20 g m(-2) year(-1)). Length and width of individual roots were measured from minirhizotron video images bimonthly over 4 years starting when the seedlings were 1.5 years old. Neither CO2 nor N-fertilization treatments affected the seasonal patterns of root production or mortality. Yearly values of fine-root length standing crop (m m(-2)), production (m m(-2) year(-1)), and mortality (m m(-2) year(-1)) were consistently higher in elevated CO2 treatments throughout the study, except for mortality in the first year; however, the only statistically significant CO2 effects were in the fine-root length standing crop (m m(-2)) in the second and third years, and production and mortality (m m(-2) year(-1)) in the third year. Higher mortality (m m(-2) year(-1)) in elevated CO2 was due to greater standing crop rather than shorter life span, as fine roots lived longer in elevated CO2. No significant N effects were noted for annual cumulative production, cumulative mortality, or mean standing crop. N availability did not significantly affect responses of fine-root standing crop, production, or mortality to elevated CO2. Multi-year studies at all life stages of trees are important to characterize belowground responses to factors such as atmospheric CO2 and N-fertilization. This study showed the potential for juvenile ponderosa pine to increase fine-root C pools and C fluxes through root mortality in response to elevated CO2.
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Affiliation(s)
- Donald L Phillips
- U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Western Ecology Division, 200 SW 35th St., Corvallis, OR, 97333, USA.
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Abstract
Soil nutrients are distributed in a non-uniform or 'patchy' manner. It is well established that the modular nature of root systems allows them to show both morphological and/or physiological plasticity upon encountering nutrient-rich patches. These plastic responses are widely believed to be foraging mechanisms by the plant to enhance nutrient resource capture. Although morphological plasticity has traditionally been viewed as the more expensive option as it requires new root construction, more recent evidence suggests this may not necessarily be the case. Moreover, plants may be able to recapture most of the initial outlay involved in new root construction, again lowering the overall cost to the plant. Under natural conditions the roots of most plant species have an additional nutrient acquisition mechanism namely mycorrhizal symbiosis. However, the impact of these important symbiotic associations upon the host plant's response to nutrient patches has received relatively little attention. The mycorrhizal fungal symbiont should, in theory, be better able to compete directly with the rest of the microbial community for the nutrients in the patch. This could potentially be important to the host plant, as generally, root proliferation responses are more important for interspecific plant, than plant-microbial, competition.
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Affiliation(s)
- A Hodge
- Department of Biology, Area 14, PO Box 373, University of York, York YO10 5YW, UK.
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Corbeels M, McMurtrie R, Pepper D, O’Connell A. A process-based model of nitrogen cycling in forest plantations. Ecol Modell 2005. [DOI: 10.1016/j.ecolmodel.2005.07.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Hishi T, Takeda H. Dynamics of heterorhizic root systems: protoxylem groups within the fine-root system of Chamaecyparis obtusa. THE NEW PHYTOLOGIST 2005; 167:509-21. [PMID: 15998402 DOI: 10.1111/j.1469-8137.2005.01418.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
To understand the physiology of fine-root functions in relation to soil organic sources, the heterogeneity of individual root functions within a fine-root system requires investigation. Here the heterogeneous dynamics within fine-root systems are reported. The fine roots of Chamaecyparis obtusa were sampled using a sequential ingrowth core method over 2 yr. After color categorization, roots were classified into protoxylem groups from anatomical observations. The root lengths with diarch and triarch groups fluctuated seasonally, whereas the tetrarch root length increased. The percentage of secondary root mortality to total mortality increased with increasing amounts of protoxylem. The carbon : nitrogen ratio indicated that the decomposability of primary roots might be greater than that of secondary roots. The position of diarch roots was mostly apical, whereas tetrarch roots tended to be distributed in basal positions within the root architecture. We demonstrate the heterogeneous dynamics within a fine-root system of C. obtusa. Fine-root heterogeneity should affect soil C dynamics. This heterogeneity is determined by the branching position within the root architecture.
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Affiliation(s)
- Takuo Hishi
- Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
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41
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References. ADV ECOL RES 2005. [DOI: 10.1016/s0065-2504(05)38015-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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42
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Guo DL, Mitchell RJ, Hendricks JJ. Fine root branch orders respond differentially to carbon source-sink manipulations in a longleaf pine forest. Oecologia 2004; 140:450-7. [PMID: 15179577 DOI: 10.1007/s00442-004-1596-1] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2003] [Accepted: 04/20/2004] [Indexed: 10/26/2022]
Abstract
Fine roots are a key component of carbon (C) flow and nitrogen (N) cycling in forest ecosystems. However, the complexity and heterogeneity of the fine root branching system have hampered the assessment and prediction of C and N dynamics at ecosystem scales. We examined how root morphology, biomass, and chemistry differed with root branch orders (1-5 with root tips classified as first order roots) and how different root orders responded to increased C sink strength (via N fertilization) and reduced carbon source strength (via canopy scorching) in a longleaf pine (Pinus palustris L.) ecosystem. With increasing root order, the diameter and length of individual roots increased, whereas the specific root length decreased. Total root biomass on an areal basis was similar among the first four orders but increased for the fifth order roots. Consequently, total root length and total root surface area decreased systematically with increasing root order. Fine root N and lignin concentrations decreased, while total non-structural carbohydrate (TNC) and cellulose concentrations increased with increasing root order. N addition and canopy disturbance did not alter root morphology, but they did influence root chemistry. N fertilization increased fine root N concentration and content per unit area in all five orders, while canopy scorching decreased root N concentration. Moreover, TNC concentration and content in fifth order roots were also reduced by canopy scorching. Our results indicate that the small, fragile, and more easily overlooked first and second order roots may be disproportionately important in ecosystem scale C and N fluxes due to their large proportions of fine root biomass, high N concentrations, relatively short lifespans, and potentially high decomposition rates.
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Affiliation(s)
- Dali L Guo
- Jones Ecological Research Center, Route 2, Box 2324, Newton, GA 39870, USA.
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Ruess RW, Hendrick RL, Burton AJ, Pregitzer KS, Sveinbjornssön B, Allen MF, Maurer GE. COUPLING FINE ROOT DYNAMICS WITH ECOSYSTEM CARBON CYCLING IN BLACK SPRUCE FORESTS OF INTERIOR ALASKA. ECOL MONOGR 2003. [DOI: 10.1890/02-4032] [Citation(s) in RCA: 208] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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44
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45
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Craine JM, Lee WG. Covariation in leaf and root traits for native and non-native grasses along an altitudinal gradient in New Zealand. Oecologia 2003; 134:471-8. [PMID: 12647118 DOI: 10.1007/s00442-002-1155-6] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2002] [Accepted: 11/11/2002] [Indexed: 10/24/2022]
Abstract
Across 30 grassland sites in New Zealand that ranged from native alpine grasslands to low elevation improved pastures, there were consistent patterns of leaf and root traits and significant differences between native and non-native grasses. Plants of high altitude sites have low N concentrations in both their leaves and roots, have thick leaves and roots, yet no differences in tissue density or photosynthetic water use efficiency when compared to plants of low altitude sites. Both the leaves and roots of the low altitude plants were enriched in (15)N relative to the plants of higher altitude, indicating that the low-N set of traits is associated with a more closed N cycle at high altitude. A second independent set of correlations shows that plants of wetter habitats have lower photosynthetic water use efficiency (more negative partial differential (13)C) and lower leaf and root tissue density than the plants of drier sites. For both leaves and roots, plants of native species consistently had traits associated with lower resource availability: lower N concentrations, denser tissues, more negative partial differential (15)N, and more positive partial differential (13)C than non-native species. If root %N is correlated with root longevity as has been shown in other systems, root longevity may be able to be predicted from simple measurements of leaf %N, though a hysteresis in the relationship between leaf and root N concentrations may make prediction of high longevity roots difficult.
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Affiliation(s)
- J M Craine
- Landcare Research, Private Mail Bag 1930, Dunedin, New Zealand.
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46
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West JB, Espeleta JF, Donovan LA. Root longevity and phenology differences between two co-occurring savanna bunchgrasses with different leaf habits. Funct Ecol 2003. [DOI: 10.1046/j.1365-2435.2003.00695.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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47
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Hiers JK, Mitchell RJ, Boring LR, Hendricks JJ, Wyatt R. Legumes native to longleaf pine savannas exhibit capacity for high N 2 -fixation rates and negligible impacts due to timing of fire. THE NEW PHYTOLOGIST 2003; 157:327-338. [PMID: 33873644 DOI: 10.1046/j.1469-8137.2003.00679.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
• N2 fixation rates of three legume species and the impact of fire regime are reported. • Summer, winter, and no burn treatments were applied. N 2 fixation rates ( 15 N isotope dilution) and C trade-offs with flowering and fine root turnover were examined in response to season of burn. • Tephrosia and Centrosema had uniformly high percentage N dfa across all treatments (74-92% N dfa ), whereas Rhynchosia showed limited N 2 fixation activity (18% and 0%). No evidence for decreased N 2 fixation due to loss of leaf area following growing season burns was found. Moreover, no consistent evidence for decreased N 2 fixation with greater flowering or fine root turnover was observed. • Despite species differences in response to fire regime, the following patterns emerged: when increased N 2 fixation is associated with decreased growth rates, legumes show limited N 2 fixation rates (as seen in Rhynchosia ). Alternatively, if greater N 2 fixation is related to increased growth rates, then legumes experience C limitations to N 2 fixation only in small individuals or during periods of rapid growth (as in Centrosema ). Reproduction may influence N 2 -fixation, but, as in the case of Tephrosia , the relationship was positive, opposite to patterns indicative of C trade-offs.
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Affiliation(s)
- J K Hiers
- Joseph W
- Jones Ecological Research Center, RR 2 Box 2324, Newton, GA 31770, USA
- Institute of Ecology, University of Georgia, Athens, GA 30602, USA
| | | | - L R Boring
- Joseph W
- Jones Ecological Research Center, RR 2 Box 2324, Newton, GA 31770, USA
| | - J J Hendricks
- Jones Ecological Research Center, RR 2 Box 2324, Newton, GA 31770, USA
- State University of West Georgia, Biology Department, Carrollton, GA 30118, USA
| | - R Wyatt
- Highlands Biological Station, PO Box 580, Highlands, NC 28741, USA
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48
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Peters DP. Plant species dominance at a grassland–shrubland ecotone: an individual-based gap dynamics model of herbaceous and woody species. Ecol Modell 2002. [DOI: 10.1016/s0304-3800(01)00460-4] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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49
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King JS, Albaugh TJ, Allen HL, Buford M, Strain BR, Dougherty P. Below-ground carbon input to soil is controlled by nutrient availability and fine root dynamics in loblolly pine. THE NEW PHYTOLOGIST 2002; 154:389-398. [PMID: 33873440 DOI: 10.1046/j.1469-8137.2002.00393.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
• Availability of growth limiting resources may alter root dynamics in forest ecosystems, possibly affecting the land-atmosphere exchange of carbon. This was evaluated for a commercially important southern timber species by installing a factorial experiment of fertilization and irrigation treatments in an 8-yr-old loblolly pine (Pinus taeda) plantation. • After 3 yr of growth, production and turnover of fine, coarse and mycorrhizal root length was observed using minirhizotrons, and compared with stem growth and foliage development. • Fertilization increased net production of fine roots and mycorrhizal roots, but did not affect coarse roots. Fine roots had average lifespans of 166 d, coarse roots 294 d and mycorrhizal roots 507 d. Foliage growth rate peaked in late spring and declined over the remainder of the growing season, whereas fine roots experienced multiple growth flushes in the spring, summer and fall. • We conclude that increased nutrient availability might increase carbon input to soils through enhanced fine root turnover. However, this will depend on the extent to which mycorrhizal root formation is affected, as these mycorrhizal roots have much longer average lifespans than fine and coarse roots.
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Affiliation(s)
- John S King
- School of Forestry and Wood Products, Michigan Technological University, Houghton, MI 49931, USA
| | - Timothy J Albaugh
- Forest Nutrition Cooperative, North Carolina State University, Raleigh, NC 27695, USA
| | - H Lee Allen
- Forest Nutrition Cooperative, North Carolina State University, Raleigh, NC 27695, USA
| | - Marilyn Buford
- USDA Forest Service, South-east Experiment Station, Research Triangle Park, NC 27709, USA
| | - Boyd R Strain
- Department of Botany, Duke University, Durham, NC 27708, USA
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Pregitzer KS, DeForest JL, Burton AJ, Allen MF, Ruess RW, Hendrick RL. FINE ROOT ARCHITECTURE OF NINE NORTH AMERICAN TREES. ECOL MONOGR 2002. [DOI: 10.1890/0012-9615(2002)072[0293:fraonn]2.0.co;2] [Citation(s) in RCA: 651] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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