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Bereczki K, Tóth EG, Szili-Kovács T, Megyes M, Korponai K, Lados BB, Illés G, Benke A, Márialigeti K. Soil Parameters and Forest Structure Commonly Form the Microbiome Composition and Activity of Topsoil Layers in Planted Forests. Microorganisms 2024; 12:1162. [PMID: 38930544 PMCID: PMC11205539 DOI: 10.3390/microorganisms12061162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 05/31/2024] [Accepted: 06/03/2024] [Indexed: 06/28/2024] Open
Abstract
Soil bacterial communities play a remarkable role in nutrient cycling, significantly affecting soil organic material content, soil fertility, and, in an indirect way, plant succession processes. Conversely, vegetation type influences microbial soil life. The present study compared the bacterial microbiome composition, diversity and catabolic activity profile of topsoil samples collected under three different forest types (a twice-coppiced black locust stand, a young, naturally reforested, and a middle-aged mixed pedunculate oak stand) planted on former arable land in the early 20th century. Diversity indices determined during 16S ribosomal RNA sequencing-based metagenome analysis indicated that the black locust stand had the highest soil bacterial community diversity. At the phylum level, Acidobacteriota, Actinobacteriota, Proteobacteria, Verrucomicrobiota, Bacteroidota, and Gemmatimonadota were the most abundant taxa in the forest soils. Concerning soil parameters, redundancy analysis revealed that pH had the highest impact on bacterial community structure and pH, and soil organic carbon content on the samples' respiration patterns. As for catabolic activity, the recently clearcut oak forest showed the lowest substrate-induced respiration, and citrate was the main driver for the inter-stand variability of microbial activity. Our results confirm that soil parameters and forest type influence the composition and functioning of the soil bacterial microbiome.
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Affiliation(s)
- Katalin Bereczki
- Doctoral School of Environmental Sciences, Eötvös Loránd University, 1117 Budapest, Hungary;
- Department of Forest Management and Ecology, Forest Research Institute, University of Sopron, 9600 Sárvár, Hungary;
| | - Endre György Tóth
- National Coalition of Independent Scholars (NCIS), Brattleboro, VT 05301, USA;
| | - Tibor Szili-Kovács
- Institute for Soil Sciences, Centre for Agricultural Research, 1022 Budapest, Hungary;
| | - Melinda Megyes
- Doctoral School of Environmental Sciences, Eötvös Loránd University, 1117 Budapest, Hungary;
| | - Kristóf Korponai
- Department of Plant Molecular Biology, Agricultural Institute, Centre for Agricultural Research, 2462 Martonvásár, Hungary;
| | - Botond Boldizsár Lados
- Department of Forestry Breeding, Forest Research Institute, University of Sopron, 9600 Sárvár, Hungary; (B.B.L.); (A.B.)
| | - Gábor Illés
- Department of Forest Management and Ecology, Forest Research Institute, University of Sopron, 9600 Sárvár, Hungary;
| | - Attila Benke
- Department of Forestry Breeding, Forest Research Institute, University of Sopron, 9600 Sárvár, Hungary; (B.B.L.); (A.B.)
| | - Károly Márialigeti
- Department of Microbiology, Eötvös Loránd University, 1117 Budapest, Hungary;
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Maitra P, Hrynkiewicz K, Szuba A, Jagodziński AM, Al-Rashid J, Mandal D, Mucha J. Metabolic niches in the rhizosphere microbiome: dependence on soil horizons, root traits and climate variables in forest ecosystems. FRONTIERS IN PLANT SCIENCE 2024; 15:1344205. [PMID: 38645395 PMCID: PMC11026606 DOI: 10.3389/fpls.2024.1344205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Accepted: 03/18/2024] [Indexed: 04/23/2024]
Abstract
Understanding belowground plant-microbial interactions is important for biodiversity maintenance, community assembly and ecosystem functioning of forest ecosystems. Consequently, a large number of studies were conducted on root and microbial interactions, especially in the context of precipitation and temperature gradients under global climate change scenarios. Forests ecosystems have high biodiversity of plants and associated microbes, and contribute to major primary productivity of terrestrial ecosystems. However, the impact of root metabolites/exudates and root traits on soil microbial functional groups along these climate gradients is poorly described in these forest ecosystems. The plant root system exhibits differentiated exudation profiles and considerable trait plasticity in terms of root morphological/phenotypic traits, which can cause shifts in microbial abundance and diversity. The root metabolites composed of primary and secondary metabolites and volatile organic compounds that have diverse roles in appealing to and preventing distinct microbial strains, thus benefit plant fitness and growth, and tolerance to abiotic stresses such as drought. Climatic factors significantly alter the quantity and quality of metabolites that forest trees secrete into the soil. Thus, the heterogeneities in the rhizosphere due to different climate drivers generate ecological niches for various microbial assemblages to foster beneficial rhizospheric interactions in the forest ecosystems. However, the root exudations and microbial diversity in forest trees vary across different soil layers due to alterations in root system architecture, soil moisture, temperature, and nutrient stoichiometry. Changes in root system architecture or traits, e.g. root tissue density (RTD), specific root length (SRL), and specific root area (SRA), impact the root exudation profile and amount released into the soil and thus influence the abundance and diversity of different functional guilds of microbes. Here, we review the current knowledge about root morphological and functional (root exudation) trait changes that affect microbial interactions along drought and temperature gradients. This review aims to clarify how forest trees adapt to challenging environments by leveraging their root traits to interact beneficially with microbes. Understanding these strategies is vital for comprehending plant adaptation under global climate change, with significant implications for future research in plant biodiversity conservation, particularly within forest ecosystems.
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Affiliation(s)
- Pulak Maitra
- Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland
| | - Katarzyna Hrynkiewicz
- Department of Microbiology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, Toruń, Poland
| | - Agnieszka Szuba
- Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland
| | - Andrzej M. Jagodziński
- Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland
- Department of Game Management and Forest Protection, Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, Poznań, Poland
| | - Jubair Al-Rashid
- Tianjin Institute of Industrial Biotechnology, University of Chinese Academy of Sciences, Tianjin, China
| | - Dipa Mandal
- Institute of Microbiology, University of Chinese Academy of Sciences, Beijing, China
| | - Joanna Mucha
- Institute of Dendrology, Polish Academy of Sciences, Kórnik, Poland
- Department of Forest Entomology and Pathology, Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, Poznań, Poland
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Huang LJ, Yang W, Chen J, Yu P, Wang Y, Li N. Molecular identification and functional characterization of an environmental stress responsive glutaredoxin gene ROXY1 in Quercus glauca. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 207:108367. [PMID: 38237422 DOI: 10.1016/j.plaphy.2024.108367] [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: 09/24/2023] [Revised: 12/03/2023] [Accepted: 01/10/2024] [Indexed: 03/16/2024]
Abstract
Quercus glauca is a valuable natural resource with both economic and ecological values. It is one of the dominant forest tree species widely distributed in Southern China. As a perennial broadleaf plant, Q. glauca inevitably encounters numerous stresses from environment. Glutaredoxins (GRXs) are a kind of small oxidoreductases that play an important role in response to oxidative stress. CC-type GRXs also known as ROXYs are specific to land plants. In this study, we isolated a CC-type GRX gene, QgROXY1, from Q. glauca. Expression of QgROXY1 is induced by a variety of environmental stimuli. QgROXY1 protein localizes to both cytoplasm and nucleus; whereas the nucleus localized QgROXY1 could physically interact with the basic region/leucine zipper motif (bZIP) transcription factor AtTGA2 from Arabidopsis thaliana. Transgenic A. thaliana ectopically expressing QgROXY1 is hypersensitive to exogenously applied salicylic acid. Induction of plant defense gene is significantly impaired in QgROXY1 transgenic plants that results in enhanced susceptibility to infection of Botrytis cinerea pathogen, indicating the evolutionary conserved function among ROXY homologs in weedy and woody plants. This is the first described function for the ROXYs in tree plants. Through this case study, we demonstrated the feasibility and efficacy of molecular technology applied to characterization of gene function in tree species.
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Affiliation(s)
- Li-Jun Huang
- College of Forestry, Central South University of Forestry and Technology, Changsha, 410004, China.
| | - Wenhai Yang
- College of Forestry, Central South University of Forestry and Technology, Changsha, 410004, China
| | - Jiali Chen
- College of Forestry, Central South University of Forestry and Technology, Changsha, 410004, China; Key Laboratory of Forest Bio-resources and Integrated Pest Management for Higher Education in Hunan Province, Central South University of Forestry and Technology, Changsha, 410004, China
| | - Peiyao Yu
- College of Forestry, Central South University of Forestry and Technology, Changsha, 410004, China; Key Laboratory of Forest Bio-resources and Integrated Pest Management for Higher Education in Hunan Province, Central South University of Forestry and Technology, Changsha, 410004, China
| | - Yukun Wang
- College of Forestry, Central South University of Forestry and Technology, Changsha, 410004, China
| | - Ning Li
- College of Forestry, Central South University of Forestry and Technology, Changsha, 410004, China; Key Laboratory of Forest Bio-resources and Integrated Pest Management for Higher Education in Hunan Province, Central South University of Forestry and Technology, Changsha, 410004, China.
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Yang H, Zhang P, Wang Q, Deng S, He X, Zhang X, Wang R, Feng Q, Yin H. Temperature rather than N availability determines root exudation of alpine coniferous forests on the eastern Tibetan Plateau along elevation gradients. TREE PHYSIOLOGY 2023; 43:1479-1492. [PMID: 37209171 DOI: 10.1093/treephys/tpad067] [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: 12/16/2022] [Revised: 05/12/2023] [Accepted: 05/15/2023] [Indexed: 05/22/2023]
Abstract
Root exudation fulfills fundamental roles in regulating carbon (C)-nutrient cycling in forest ecosystems, yet the main ecological drivers of root exudation and underlying mechanisms in forests under natural gradients remain poorly understood. Here, we investigated the intraspecific variation of root exudation rates in two alpine coniferous forests (Abies faxoniana Rehder et Wilson and Abies georgei Orr) along two elevation gradients on the eastern Tibetan Plateau. Meanwhile, the fine root traits and associated climate and soil parameters were assessed to examine the effects of elevation-dependent changes in climatic and soil nutrient conditions on root exudation. Results showed that root exudation rates decreased with increasing elevation and were positively correlated with mean air temperature. However, the relationships of root exudation with soil moisture and soil nitrogen availability were not significant. The structural equation model (SEM) further revealed that air temperature affected root exudation both directly and indirectly through the effects on fine root morphology and biomass, implying that the adaption of root C allocation and fine root morphological traits to low temperatures primarily resulted in declined root exudation at higher elevations. These results highlight the perceived importance of temperature in determining the elevational variation of root exudation in alpine coniferous forests, which has foreseeably great implications for the exudate-mediated ecosystem C and nutrient processes in the face of drastic warming on the eastern Tibetan Plateau.
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Affiliation(s)
- Han Yang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province & China-Croatia "Belt and Road" Joint Laboratory on Biodiversity and Ecosystem Services, Chengdu Institute of Biology, Chinese Academy of Sciences, No. 9 Section 4 South Renmin Road, Wuhou District, Chengdu, Sichuan 610041, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Peipei Zhang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province & China-Croatia "Belt and Road" Joint Laboratory on Biodiversity and Ecosystem Services, Chengdu Institute of Biology, Chinese Academy of Sciences, No. 9 Section 4 South Renmin Road, Wuhou District, Chengdu, Sichuan 610041, China
| | - Qitong Wang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province & China-Croatia "Belt and Road" Joint Laboratory on Biodiversity and Ecosystem Services, Chengdu Institute of Biology, Chinese Academy of Sciences, No. 9 Section 4 South Renmin Road, Wuhou District, Chengdu, Sichuan 610041, China
| | - Shaojun Deng
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province & China-Croatia "Belt and Road" Joint Laboratory on Biodiversity and Ecosystem Services, Chengdu Institute of Biology, Chinese Academy of Sciences, No. 9 Section 4 South Renmin Road, Wuhou District, Chengdu, Sichuan 610041, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Xi He
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province & China-Croatia "Belt and Road" Joint Laboratory on Biodiversity and Ecosystem Services, Chengdu Institute of Biology, Chinese Academy of Sciences, No. 9 Section 4 South Renmin Road, Wuhou District, Chengdu, Sichuan 610041, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Xinjun Zhang
- Institute of Tibet Plateau Ecology & Key Laboratory of Forest Ecology in Tibet Plateau, Tibet Agriculture & Animal Husbandry University, No. 8 Xueyuan Road, Bayi District, Nyingchi, Tibet 860000, China
| | - Ruihong Wang
- Institute of Tibet Plateau Ecology & Key Laboratory of Forest Ecology in Tibet Plateau, Tibet Agriculture & Animal Husbandry University, No. 8 Xueyuan Road, Bayi District, Nyingchi, Tibet 860000, China
| | - Qiuhong Feng
- Sichuan Wolong Forest Ecosystem Research Station, Sichuan Academy of Forestry, No. 18 Xinghui West Road, Jinniu District, Chengdu, Sichuan 610081, China
| | - Huajun Yin
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province & China-Croatia "Belt and Road" Joint Laboratory on Biodiversity and Ecosystem Services, Chengdu Institute of Biology, Chinese Academy of Sciences, No. 9 Section 4 South Renmin Road, Wuhou District, Chengdu, Sichuan 610041, China
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Ping Q, Fang C, Yuan X, Agathokleous E, He H, Zheng H, Feng Z. Nitrogen addition changed the relationships of fine root respiration and biomass with key physiological traits in ozone-stressed poplars. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 875:162721. [PMID: 36898537 DOI: 10.1016/j.scitotenv.2023.162721] [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: 11/26/2022] [Revised: 03/02/2023] [Accepted: 03/04/2023] [Indexed: 06/18/2023]
Abstract
Increasing ozone (O3) and nitrogen (N) addition may have contradictory effects on plant photosynthesis and growth. However, it remains unclear whether these effects on aboveground parts further change the root resource management strategy and the relationships of fine root respiration and biomass with other physiological traits. In this study, an open-top chamber experiment was conducted to investigate the effects of O3 alone and in combination with nitrogen (N) addition on root production and fine root respiration of poplar clone 107 (Populus × euramericana cv. '74/76'). Saplings were grown with (100 kg ha-1 year-1) or without (+0 kg ha-1 year-1) N addition under two O3 regimes (non-filtered ambient air or non-filtered ambient air + 60 ppb of O3). After about two to three months of treatment, elevated O3 significantly decreased fine root biomass and starch content but increased fine root respiration, which occurred in tandem with inhibited leaf light-saturated photosynthetic rate (Asat). Nitrogen addition did not change fine root respiration or biomass, neither did it alter the effect of elevated O3 on the fine root traits. However, N addition weakened the relationships of fine root respiration and biomass with Asat, fine root starch and N concentrations. No significant relationships of fine root biomass and respiration with soil mineralized N were observed under elevated O3 or N addition. These results imply that changed relationships of plant fine root traits under global changes should be considered into earth system process models to project more accurately future carbon cycle.
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Affiliation(s)
- Qin Ping
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing Road 18, Haidian District, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chao Fang
- Key Laboratory of Ecosystem Carbon Source and Sink, China Meteorological Administration (ECSS-CMA), School of Applied Meteorology, Nanjing University of Information Science & Technology, 219 Ningliu Road, Nanjing 210044, China
| | - Xiangyang Yuan
- Key Laboratory of Ecosystem Carbon Source and Sink, China Meteorological Administration (ECSS-CMA), School of Applied Meteorology, Nanjing University of Information Science & Technology, 219 Ningliu Road, Nanjing 210044, China
| | - Evgenios Agathokleous
- Key Laboratory of Ecosystem Carbon Source and Sink, China Meteorological Administration (ECSS-CMA), School of Applied Meteorology, Nanjing University of Information Science & Technology, 219 Ningliu Road, Nanjing 210044, China.
| | - Hongxing He
- Department of Geography, McGill University, Montréal, Quebec H3A OB9, Canada
| | - Hua Zheng
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing Road 18, Haidian District, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhaozhong Feng
- Key Laboratory of Ecosystem Carbon Source and Sink, China Meteorological Administration (ECSS-CMA), School of Applied Meteorology, Nanjing University of Information Science & Technology, 219 Ningliu Road, Nanjing 210044, China.
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Hickey LJ, Nave LE, Nadelhoffer KJ, Clay C, Marini AI, Gough CM. Mechanistically-grounded pathways connect remotely sensed canopy structure to soil respiration. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158267. [PMID: 36030858 DOI: 10.1016/j.scitotenv.2022.158267] [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: 05/25/2022] [Revised: 08/19/2022] [Accepted: 08/20/2022] [Indexed: 06/15/2023]
Abstract
Variation in the soil-to-atmosphere C flux, or soil respiration (Rs), is influenced by a suite of biotic and abiotic factors, including soil temperature, soil moisture, and root biomass. However, whether light detection and ranging (lidar)-derived canopy structure is tied to soil respiration through its simultaneous influence over these drivers is not known. We assessed relationships between measures of above- and belowground vegetation density and complexity, and evaluated whether Rs is linked to remotely sensed canopy structure through pathways mediated by established biotic and abiotic mechanisms. Our results revealed that, at the stand-scale, canopy rugosity-a measure of complexity-and vegetation area index were coupled to soil respiration through their effects on light interception, soil microclimate, and fine root mass density, but this connection was stronger for complexity. Canopy and root complexity were not spatially coupled at the stand-scale, with canopy but not root complexity increasing through stand development. Our findings suggest that remotely sensed canopy complexity could be used to infer spatial variation in Rs, and that this relationship is grounded in known mechanistic pathways. The broad spatial inference of soil respiration via remotely sensed canopy complexity requires multi-site observations of canopy structure and Rs, which is possible given burgeoning open data from ecological networks and satellite remote sensing platforms.
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Affiliation(s)
- Laura J Hickey
- Biology Department, Virginia Commonwealth University, Richmond, VA, USA.
| | - Lucas E Nave
- Biological Station and Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
| | - Knute J Nadelhoffer
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
| | - Cameron Clay
- Biology Department, Virginia Commonwealth University, Richmond, VA, USA
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Kawakami E, Ataka M, Kume T, Shimono K, Harada M, Hishi T, Katayama A. Root exudation in a sloping Moso bamboo forest in relation to fine root biomass and traits. PLoS One 2022; 17:e0266131. [PMID: 35324979 PMCID: PMC8947071 DOI: 10.1371/journal.pone.0266131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 03/14/2022] [Indexed: 11/18/2022] Open
Abstract
Exudation by fine roots generally varies with their morphological traits, but the effect of belowground resource availability on the root exudation via root morphological traits and biomass remains unknown. We aimed to determine the effects of morphological and physiological traits on root exudation rates and to estimate stand-scale exudation (Estand) by measuring the mass, length, and surface area of fine roots in a Moso bamboo forest. We measured root exudation as well as morphological and physiological traits in upper and lower plots on a slope with different belowground resource availability. The mean (± S.D.) root exudation rates per mass in the upper and lower slope were 0.049 ± 0.047 and 0.040 ± 0.059 mg C g-1 h-1, respectively, which were in the range of exudation found in woody forest ecosystems. We observed significant relationships between root exudation per mass and root respiration, as well as specific root length and surface area. In contrast, exudation per length and area did not correlate with morphological traits. The morphological traits did not differ between slope positions, resulting in no significant difference in root exudation per mass. Fine root biomass, length, and surface area on a unit ground basis were much higher in the lower than those in the upper slope positions. Estand was higher when estimated by mass than by length and area because the morphological effect on exudation was ignored when scaled using mass. Estand was 1.4–2.0-fold higher in the lower than that in upper slope positions, suggesting that the scaling parameters of mass, length, and area determined the Estand estimate more than the exudation rate per mass, length, and area. Regardless of scaling, Estand was much higher in the Moso bamboo forest than in other forest ecosystems because of a large fine-root biomass.
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Affiliation(s)
- Erika Kawakami
- Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Nishiku, Fukuoka, Japan
| | - Mioko Ataka
- Research Institute for Sustainable Humanosphere, Uji, Kyoto, Japan
| | - Tomonori Kume
- Shiiba Research Forest, Kyushu University, Shiiba, Miyazaki, Japan
| | - Kohei Shimono
- Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Nishiku, Fukuoka, Japan
| | - Masayoshi Harada
- Faculty of Agriculture, Kyushu University, Nishiku, Fukuoka, Japan
| | - Takuo Hishi
- Kasuya Research Forest, Kyushu University, Sasaguri, Fukuoka, Japan
| | - Ayumi Katayama
- Shiiba Research Forest, Kyushu University, Shiiba, Miyazaki, Japan
- * E-mail:
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Suitability and Sensitivity of the Potential Distribution of Cyclobalanopsis glauca Forests under Climate Change Conditions in Guizhou Province, Southwestern China. ATMOSPHERE 2022. [DOI: 10.3390/atmos13030456] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Global climate change is becoming increasingly prominent and has already begun to influence natural biological systems. Assessing the potential impact of climate change on ecosystems is an important research topic of the International Geosphere-Biosphere Programme (IGBP). Based on current distribution data, climate data, climate change scenarios (RCP8.5 scenario, 2070–2099), and application of the MaxEnt model, this study assessed suitability and sensitivity of the potential distribution of Cyclobalanopsis glauca forests under climate change conditions in Guizhou Province. The results were as follows: (1) Area under the curve values of training data and texting data indicated excellent performance of the model; (2) Compared to the current climate, areas of probability <0.4 were decreased, and the other areas presented an increasing trend under the RCP8.5 scenario; (3) Positive sensitivity areas were much larger than negative sensitivity areas under climate change. In either case, slight sensitivity areas accounted for the largest proportion; (4) The mean altitude of slight sensitivity areas measured the lowest, and highly negative sensitivity areas were the highest.
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Wen Z, White PJ, Shen J, Lambers H. Linking root exudation to belowground economic traits for resource acquisition. THE NEW PHYTOLOGIST 2022; 233:1620-1635. [PMID: 34761404 DOI: 10.1111/nph.17854] [Citation(s) in RCA: 55] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 11/04/2021] [Indexed: 06/13/2023]
Abstract
The concept of a root economics space (RES) is increasingly adopted to explore root trait variation and belowground resource-acquisition strategies. Much progress has been made on interactions of root morphology and mycorrhizal symbioses. However, root exudation, with a significant carbon (C) cost (c. 5-21% of total photosynthetically fixed C) to enhance resource acquisition, remains a missing link in this RES. Here, we argue that incorporating root exudation into the structure of RES is key to a holistic understanding of soil nutrient acquisition. We highlight the different functional roles of root exudates in soil phosphorus (P) and nitrogen (N) acquisition. Thereafter, we synthesize emerging evidence that illustrates how root exudation interacts with root morphology and mycorrhizal symbioses at the level of species and individual plant and argue contrasting patterns in species evolved in P-impoverished vs N-limited environments. Finally, we propose a new conceptual framework, integrating three groups of root functional traits to better capture the complexity of belowground resource-acquisition strategies. Such a deeper understanding of the integrated and dynamic interactions of root morphology, root exudation, and mycorrhizal symbioses will provide valuable insights into the mechanisms underlying species coexistence and how to explore belowground interactions for sustainable managed systems.
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Affiliation(s)
- Zhihui Wen
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, 100193, Beijing, China
| | - Philip J White
- Ecological Science Group, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Jianbo Shen
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, 100193, Beijing, China
| | - Hans Lambers
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, 100193, Beijing, China
- School of Biological Sciences and Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA, 6009, Australia
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Meyer N, Xu Y, Karjalainen K, Adamczyk S, Biasi C, van Delden L, Martin A, Mganga K, Myller K, Sietiö OM, Suominen O, Karhu K. Living, dead, and absent trees-How do moth outbreaks shape small-scale patterns of soil organic matter stocks and dynamics at the Subarctic mountain birch treeline? GLOBAL CHANGE BIOLOGY 2022; 28:441-462. [PMID: 34672044 DOI: 10.1111/gcb.15951] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 09/29/2021] [Accepted: 09/30/2021] [Indexed: 06/13/2023]
Abstract
Mountain birch forests (Betula pubescens Ehrh. ssp. czerepanovii) at the subarctic treeline not only benefit from global warming, but are also increasingly affected by caterpillar outbreaks from foliage-feeding geometrid moths. Both of these factors have unknown consequences on soil organic carbon (SOC) stocks and biogeochemical cycles. We measured SOC stocks down to the bedrock under living trees and under two stages of dead trees (12 and 55 years since moth outbreak) and treeless tundra in northern Finland. We also measured in-situ soil respiration, potential SOC decomposability, biological (enzyme activities and microbial biomass), and chemical (N, mineral N, and pH) soil properties. SOC stocks were significantly higher under living trees (4.1 ± 2.1 kg m²) than in the treeless tundra (2.4 ± 0.6 kg m²), and remained at an elevated level even 12 (3.7 ± 1.7 kg m²) and 55 years (4.9 ± 3.0 kg m²) after tree death. Effects of tree status on SOC stocks decreased with increasing distance from the tree and with increasing depth, that is, a significant effect of tree status was found in the organic layer, but not in mineral soil. Soil under living trees was characterized by higher mineral N contents, microbial biomass, microbial activity, and soil respiration compared with the treeless tundra; soils under dead trees were intermediate between these two. The results suggest accelerated organic matter turnover under living trees but a positive net effect on SOC stocks. Slowed organic matter turnover and continuous supply of deadwood may explain why SOC stocks remained elevated under dead trees, despite the heavy decrease in aboveground C stocks. We conclude that the increased occurrence of moth damage with climate change would have minor effects on SOC stocks, but ultimately decrease ecosystem C stocks (49% within 55 years in this area), if the mountain birch forests will not be able to recover from the outbreaks.
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Affiliation(s)
- Nele Meyer
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
- Department of Soil Ecology, University of Bayreuth, Bayreuth, Germany
| | - Yi Xu
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Katri Karjalainen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Sylwia Adamczyk
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
- Natural Resources Institute Finland (Luke), Helsinki, Finland
| | - Christina Biasi
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Lona van Delden
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
| | - Angela Martin
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Kevin Mganga
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
- Department of Agricultural Sciences, South Eastern Kenya University, Kitui, Kenya
| | - Kristiina Myller
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Outi-Maaria Sietiö
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Otso Suominen
- Biodiversity Unit, Kevo Subarctic Research Institute, University of Turku, Turku, Finland
| | - Kristiina Karhu
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
- Helsinki Institute of Life Science (Hilife), University of Helsinki, Helsinki, Finland
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11
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Wu YF, Whitaker J, Toet S, Bradley A, Davies CA, McNamara NP. Diurnal variability in soil nitrous oxide emissions is a widespread phenomenon. GLOBAL CHANGE BIOLOGY 2021; 27:4950-4966. [PMID: 34231289 DOI: 10.1111/gcb.15791] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 06/10/2021] [Indexed: 06/13/2023]
Abstract
Manual measurements of nitrous oxide (N2 O) emissions with static chambers are commonly practised. However, they generally do not consider the diurnal variability of N2 O flux, and little is known about the patterns and drivers of such variability. We systematically reviewed and analysed 286 diurnal data sets of N2 O fluxes from published literature to (i) assess the prevalence and timing (day or night peaking) of diurnal N2 O flux patterns in agricultural and forest soils, (ii) examine the relationship between N2 O flux and soil temperature with different diurnal patterns, (iii) identify whether non-diurnal factors (i.e. land management and soil properties) influence the occurrence of diurnal patterns and (iv) evaluate the accuracy of estimating cumulative N2 O emissions with single-daily flux measurements. Our synthesis demonstrates that diurnal N2 O flux variability is a widespread phenomenon in agricultural and forest soils. Of the 286 data sets analysed, ~80% exhibited diurnal N2 O patterns, with ~60% peaking during the day and ~20% at night. Contrary to many published observations, our analysis only found strong positive correlations (R > 0.7) between N2 O flux and soil temperature in one-third of the data sets. Soil drainage property, soil water-filled pore space (WFPS) level and land use were also found to potentially influence the occurrence of certain diurnal patterns. Our work demonstrated that single-daily flux measurements at mid-morning yielded daily emission estimates with the smallest average bias compared to measurements made at other times of day, however, it could still lead to significant over- or underestimation due to inconsistent diurnal N2 O patterns. This inconsistency also reflects the inaccuracy of using soil temperature to predict the time of daily average N2 O flux. Future research should investigate the relationship between N2 O flux and other diurnal parameters, such as photosynthetically active radiation (PAR) and root exudation, along with the consideration of the effects of soil moisture, drainage and land use on the diurnal patterns of N2 O flux. The information could be incorporated in N2 O emission prediction models to improve accuracy.
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Affiliation(s)
- Yuk-Faat Wu
- UK Centre for Ecology & Hydrology, Lancaster Environment Centre, Bailrigg, Lancaster, UK
- Department of Environment and Geography, University of York, Heslington, York, UK
| | - Jeanette Whitaker
- UK Centre for Ecology & Hydrology, Lancaster Environment Centre, Bailrigg, Lancaster, UK
| | - Sylvia Toet
- Department of Environment and Geography, University of York, Heslington, York, UK
| | - Amy Bradley
- UK Centre for Ecology & Hydrology, Lancaster Environment Centre, Bailrigg, Lancaster, UK
| | - Christian A Davies
- Shell International Exploration and Production Inc., Shell Technology Centre Houston, Houston, TX, USA
| | - Niall P McNamara
- UK Centre for Ecology & Hydrology, Lancaster Environment Centre, Bailrigg, Lancaster, UK
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12
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Biotic and Abiotic Determinants of Soil Organic Matter Stock and Fine Root Biomass in Mountain Area Temperate Forests—Examples from Cambisols under European Beech, Norway Spruce, and Silver Fir (Carpathians, Central Europe). FORESTS 2021. [DOI: 10.3390/f12070823] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Forest ecosystems significantly contribute to the global organic carbon (OC) pool, exhibiting high spatial heterogeneity in this respect. Some of the components of the OC pool in a forest (woody aboveground biomass (wAGB), coarse root biomass (CRB)) can be relatively easily estimated using readily available data from land observation and forest inventories, while some of the components of the OC pool are very difficult to determine (fine root biomass (FRB) and soil organic matter (SOM) stock). The main objectives of our study were to: (1) estimate the SOM stock; (2) estimate FRB; and (3) assess the relationship between both biotic (wAGB, forest age, foliage, stand density) and abiotic factors (climatic conditions, relief, soil properties) and SOM stocks and FRB in temperate forests in the Western Carpathians consisting of European beech, Norway spruce, and silver fir (32 forest inventory plots in total). We uncovered the highest wAGB in beech forests and highest SOM stocks under beech forest. FRB was the highest under fir forest. We noted a considerable impact of stand density on SOM stocks, particularly in beech and spruce forests. FRB content was mostly impacted by stand density only in beech forests without any discernible effects on other forest characteristics. We discovered significant impacts of relief-dependent factors and SOM stocks at all the studied sites. Our biomass and carbon models informed by more detailed environmental data led to reduce the uncertainty in over- and underestimation in Cambisols under beech, spruce, and fir forests for mountain temperate forest carbon pools.
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13
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Riutta T, Kho LK, Teh YA, Ewers R, Majalap N, Malhi Y. Major and persistent shifts in below-ground carbon dynamics and soil respiration following logging in tropical forests. GLOBAL CHANGE BIOLOGY 2021; 27:2225-2240. [PMID: 33462919 DOI: 10.1111/gcb.15522] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 12/01/2020] [Indexed: 06/12/2023]
Abstract
Soil respiration is the largest carbon efflux from the terrestrial ecosystem to the atmosphere, and selective logging influences soil respiration via changes in abiotic (temperature, moisture) and biotic (biomass, productivity, quantity and quality of necromass inputs) drivers. Logged forests are a predominant feature of the tropical forest landscape, their area exceeding that of intact forest. We quantified both total and component (root, mycorrhiza, litter, and soil organic matter, SOM) soil respiration in logged (n = 5) and old-growth (n = 6) forest plots in Malaysian Borneo, a region which is a global hotspot for emission from forest degradation. We constructed a detailed below-ground carbon budget including organic carbon inputs into the system via litterfall and root turnover. Total soil respiration was significantly higher in logged forests than in old-growth forests (14.3 ± 0.23 and 12.7 ± 0.60 Mg C ha-1 year-1 , respectively, p = 0.037). This was mainly due to the higher SOM respiration in logged forests (55 ± 3.1% of the total respiration in logged forests vs. 50 ± 3.0% in old-growth forests). In old-growth forests, annual SOM respiration was equal to the organic carbon inputs into the soil (difference between SOM respiration and inputs 0.18 Mg C ha-1 year-1 , with 90% confidence intervals of -0.41 and 0.74 Mg C ha-1 year-1 ), indicating that the system is in equilibrium, while in logged forests SOM respiration exceeded the inputs by 4.2 Mg C ha-1 year-1 (90% CI of 3.6 and 4.9 Mg C ha-1 year-1 ), indicating that the soil is losing carbon. These results contribute towards understanding the impact of logging on below-ground carbon dynamics, which is one of the key uncertainties in estimating emissions from forest degradation. This study demonstrates how significant perturbation of the below-ground carbon balance, and consequent net soil carbon emissions, can persist for decades after a logging event in tropical forests.
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Affiliation(s)
- Terhi Riutta
- School of Geography and the Environment, Environmental Change Institute, University of Oxford, Oxford, UK
- Department of Life Sciences, Imperial College London, Ascot, UK
| | - Lip Khoon Kho
- School of Geography and the Environment, Environmental Change Institute, University of Oxford, Oxford, UK
- Peat Ecosystem and Biodiversity, Biology and Sustainability Research Division, Malaysian Palm Oil Board, Kajang, Selangor, Malaysia
| | - Yit Arn Teh
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Thyne, UK
| | - Robert Ewers
- Department of Life Sciences, Imperial College London, Ascot, UK
| | - Noreen Majalap
- Forest Research Centre, Sabah Forestry Department, Sandakan, Sabah, Malaysia
| | - Yadvinder Malhi
- School of Geography and the Environment, Environmental Change Institute, University of Oxford, Oxford, UK
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14
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Han M, Zhu B. Linking root respiration to chemistry and morphology across species. GLOBAL CHANGE BIOLOGY 2021; 27:190-201. [PMID: 33058350 DOI: 10.1111/gcb.15391] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 09/09/2020] [Accepted: 10/07/2020] [Indexed: 05/24/2023]
Abstract
Root respiration is a critical physiological trait involved in root resource acquisition strategies, yet it is less represented in root trait syndrome. Here we compiled a large dataset of root respiration associated with root chemical and morphological traits from 245 plant species. Our results demonstrated that root respiration correlated positively with root nitrogen concentration (RNC) and negatively with root tissue density (RTD) across and within woody and non-woody species. However, the relationships between root respiration and specific root length (SRL) and root diameter (RD) were weak or even insignificant. Such root respiration-traits relationships were not completely in line with predictions by the root economics spectrum (RES). Furthermore, the principal component analysis showed that root trait syndrome was multidimensional. Root respiration was associated more strongly with the RNC-RTD axis (the classical RES) than with the orthogonal SRL-RD axis for woody species, but not for non-woody species. Collectively, the linkages of root physiological, chemical, and morphological traits provide a better understanding of root trait covariation and root resource acquisition strategies.
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Affiliation(s)
- Mengguang Han
- Institute of Ecology, College of Urban and Environmental Sciences, and Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China
| | - Biao Zhu
- Institute of Ecology, College of Urban and Environmental Sciences, and Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China
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15
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Nyam-Osor B, Byambadorj SO, Park BB, Terzaghi M, Scippa GS, Stanturf JA, Chiatante D, Montagnoli A. Root Biomass Distribution of Populus sibirica and Ulmus pumila Afforestation Stands Is Affected by Watering Regimes and Fertilization in the Mongolian Semi-arid Steppe. FRONTIERS IN PLANT SCIENCE 2021; 12:638828. [PMID: 33968099 PMCID: PMC8102691 DOI: 10.3389/fpls.2021.638828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 03/30/2021] [Indexed: 05/11/2023]
Abstract
Desertification of the semi-arid steppe of Mongolia is advancing very rapidly, motivating afforestation efforts. The "Green Belt" joint project (Government of Mongolia and Republic of Korea), which aims to mitigate soil degradation and develop agroforestry activities through the planting of a forest shelterbelt, is one such response. In these plantations, tree growth has been supported by different watering regimes (no watering, 2, 4, and 8 L h-1) and by two types of soil fertilization (NPK and Compost). The present paper analyses the effect of these techniques on soil chemistry and root biomass partitioning of Populus sibirica (Horth ex Tausch) and Ulmus pumila (L.) tree species. In July 2019, at the plantation site in Lun Soum, Tuv province (Mongolia), six trees were excavated by hand in each treatment, the root system was divided into taproot and five diameter classes (0-2; 2-5; 5-10; 10-20; > 20 mm), and the biomass was measured. Soil organic matter, macronutrients, and pH were also measured. The addition of fertilizers in the long-term did not enhance the soil chemical properties. The build-up of root biomass in both species correlated positively with increasing levels of the watering, while the application of fertilizers led to root growth suppression. For most of the root classes and both species, an irrigation level of 4 L h-1 was sufficient to yield the highest biomass and could be recommended for afforesting the semi-arid steppe of Mongolia. The root biomass of P. sibirica was more dependent on the watering regimes and of U. pumila was more negatively influenced by the application of fertilizers, indicating that U. pumila, due to the its lower water need, could be suitable for afforesting semi-arid environments. Our experiments suggest that afforestation practices in the semi-arid steppe of Mongolia should be supported by a prior analysis of plants' needs, soil type, dose, and type of fertilizers to be applied. Knowledge of the root response to the supporting techniques is necessary for choosing the best one for the plantation and, thus, to develop a sustainable and successful strategy to restore these degraded lands.
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Affiliation(s)
- Batkhuu Nyam-Osor
- Laboratory of Forest Genetics and Ecophysiology, School of Engineering and Applied Sciences, National University of Mongolia, Ulaanbaatar, Mongolia
| | - Ser-Oddamba Byambadorj
- Laboratory of Forest Genetics and Ecophysiology, School of Engineering and Applied Sciences, National University of Mongolia, Ulaanbaatar, Mongolia
- Laboratory of Silviculture, College of Agriculture and Life Science, Chungnam National University, Deajeon, South Korea
| | - Byung Bae Park
- Laboratory of Silviculture, College of Agriculture and Life Science, Chungnam National University, Deajeon, South Korea
| | - Mattia Terzaghi
- Department of Chemistry and Biology “A. Zambelli”, University of Salerno, Salerno, Italy
| | - Gabriella Stefania Scippa
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, Isernia, Italy
| | - John A. Stanturf
- Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Tartu, Estonia
| | - Donato Chiatante
- Laboratory of Environmental and Applied Botany, Department of Biotechnology and Life Science, University of Insubria, Varese, Italy
| | - Antonio Montagnoli
- Laboratory of Environmental and Applied Botany, Department of Biotechnology and Life Science, University of Insubria, Varese, Italy
- *Correspondence: Antonio Montagnoli
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16
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Sun L, Ataka M, Han M, Han Y, Gan D, Xu T, Guo Y, Zhu B. Root exudation as a major competitive fine-root functional trait of 18 coexisting species in a subtropical forest. THE NEW PHYTOLOGIST 2021; 229:259-271. [PMID: 32772392 DOI: 10.1111/nph.16865] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 08/03/2020] [Indexed: 06/11/2023]
Abstract
Root exudation stimulates microbial decomposition and enhances nutrient availability to plants. It remains difficult to measure and predict this carbon flux in natural conditions, especially for mature woody plants. Based on a known conceptual framework of root functional traits coordination, we proposed that root functional traits may predict root exudation. We measured root exudation and other seven root morphological/chemical/physiological traits for 18 coexisting woody species in a deciduous-evergreen mixed forest in subtropical China. Root exudation, respiration, diameter and nitrogen (N) concentration all exhibited significant phylogenetic signals. We found that root exudation positively correlated with competitive traits (root respiration, N concentration) and negatively with a conservative trait (root tissue density). Furthermore, these relationships were independent of phylogenetic signals. A principal component analysis showed that root exudation and morphological traits loaded on two perpendicular axes. Root exudation is a competitive trait in a multidimensional fine-root functional coordination. The metabolic dimension on which root exudation loaded was relatively independent of the morphological dimension, indicating that increasing nutrient availability by root exudation might be a complementary strategy for plant nutrient acquisition. The positive relationship between root exudation and root respiration and N concentration is a promising approach for the future prediction of root exudation.
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Affiliation(s)
- Lijuan Sun
- Key Laboratory for Earth Surface Processes of the Ministry of Education, Institute of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Mioko Ataka
- Graduate School of Agriculture, Kyoto University, Kyoto, 6068502, Japan
| | - Mengguang Han
- Key Laboratory for Earth Surface Processes of the Ministry of Education, Institute of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Yunfeng Han
- Key Laboratory for Earth Surface Processes of the Ministry of Education, Institute of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Dayong Gan
- Key Laboratory for Earth Surface Processes of the Ministry of Education, Institute of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Tianle Xu
- Key Laboratory for Earth Surface Processes of the Ministry of Education, Institute of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Yanpei Guo
- Key Laboratory for Earth Surface Processes of the Ministry of Education, Institute of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Biao Zhu
- Key Laboratory for Earth Surface Processes of the Ministry of Education, Institute of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
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17
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Prada-Salcedo LD, Goldmann K, Heintz-Buschart A, Reitz T, Wambsganss J, Bauhus J, Buscot F. Fungal guilds and soil functionality respond to tree community traits rather than to tree diversity in European forests. Mol Ecol 2020; 30:572-591. [PMID: 33226697 DOI: 10.1111/mec.15749] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 11/10/2020] [Accepted: 11/18/2020] [Indexed: 12/23/2022]
Abstract
At the global scale, most forest research on biodiversity focuses on aboveground organisms. However, understanding the structural associations between aboveground and belowground communities provides relevant information about important functions linked to biogeochemical cycles. Microorganisms such as soil fungi are known to be closely coupled to the dominant tree vegetation, and we hypothesize that tree traits affect fungal guilds and soil functionality in multiple ways. By analysing fungal diversity of 64 plots from four European forest types using Illumina DNA sequencing, we show that soil fungal communities respond to tree community traits rather than to tree species diversity. To explain changes in fungal community structure and measured soil enzymatic activities, we used a trait-based ecological approach and community-weighted means of tree traits to define 'fast' (acquisitive) versus 'slow' (conservative) tree communities. We found specific tree trait effects on different soil fungal guilds and soil enzymatic activities: tree traits associated with litter and absorptive roots correlated with fungal, especially pathogen diversity, and influenced community composition of soil fungi. Relative abundance of the symbiotrophic and saprotrophic guilds mirrored the litter quality, while the root traits of fast tree communities enhanced symbiotrophic abundance. We found that forest types of higher latitudes, which are dominated by fast tree communities, correlated with high carbon-cycling enzymatic activities. In contrast, Mediterranean forests with slow tree communities showed high enzymatic activities related to nitrogen and phosphorous. Our findings highlight that tree trait effects of either 'fast' or 'slow' tree communities drive different fungal guilds and influence biogeochemical cycles.
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Affiliation(s)
- Luis Daniel Prada-Salcedo
- Department of Soil Ecology, Helmholtz-Centre for Environmental Research - UFZ, Halle (Saale), Germany.,Department of Biology, University of Leipzig, Leipzig, Germany
| | - Kezia Goldmann
- Department of Soil Ecology, Helmholtz-Centre for Environmental Research - UFZ, Halle (Saale), Germany
| | - Anna Heintz-Buschart
- Department of Soil Ecology, Helmholtz-Centre for Environmental Research - UFZ, Halle (Saale), Germany.,German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Thomas Reitz
- Department of Soil Ecology, Helmholtz-Centre for Environmental Research - UFZ, Halle (Saale), Germany.,German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Janna Wambsganss
- Chair of Silviculture, Faculty of Environment and Natural Resources, University of Freiburg, Freiburg, Germany.,Chair of Geobotany, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Jürgen Bauhus
- Chair of Silviculture, Faculty of Environment and Natural Resources, University of Freiburg, Freiburg, Germany
| | - François Buscot
- Department of Soil Ecology, Helmholtz-Centre for Environmental Research - UFZ, Halle (Saale), Germany.,German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
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18
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Jakoby G, Rog I, Megidish S, Klein T. Enhanced root exudation of mature broadleaf and conifer trees in a Mediterranean forest during the dry season. TREE PHYSIOLOGY 2020; 40:1595-1605. [PMID: 32705136 DOI: 10.1093/treephys/tpaa092] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 05/19/2020] [Accepted: 07/06/2020] [Indexed: 06/11/2023]
Abstract
Root exudates are part of the rhizodeposition process, which is the major source of soil organic carbon (C) released by plant roots. This flux of C is believed to have profound effects on C and nutrient cycling in ecosystems. The quantity of root exudates depends on the plant species, the period throughout the year, and external biotic and abiotic factors. Since root exudates of mature trees are difficult to collect in field conditions, very little is known about their flux, especially in water-limited ecosystems, such as the seasonally hot and dry Mediterranean maquis. Here, we collected exudates from DNA-identified roots in the forest from the gymnosperm Cupressus sempervirens L. and the evergreen angiosperm Pistacia lentiscus L. by 48-h incubations on a monthly temporal resolution throughout the year. We examined relationships of the root exudate C flux to abiotic parameters of the soil (water content, water potential, temperature) and atmosphere (vapor pressure deficit, temperature). We also studied relationships to C fluxes through the leaves as indicators of tree C balance. Root exudation rates varied significantly along the year, increasing from 6 μg C cm -2 root day-1 in both species in the wet season to 4- and 11-fold rates in Pistacia and Cupressus, respectively, in the dry season. A stepwise linear mixed-effects model showed that the three soil parameters were the most influential on exudation rates. Among biotic factors, there was a significant negative correlation of exudation rate with leaf assimilation in Cupressus and a significant negative correlation with leaf respiration in Pistacia. Our observation of enhanced exudation flux during the dry season indicates that exudation dynamics in the field are less sensitive to the low tree C availability in the dry season. The two key Mediterranean forest species seem to respond to seasonal changes in the rhizosphere such as drying and warming, and therefore invest C in the rhizosphere under seasonal drought.
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Affiliation(s)
- Gilad Jakoby
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ido Rog
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Shacham Megidish
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Tamir Klein
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
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19
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Akatsuki M, Makita N. Influence of fine root traits on in situ exudation rates in four conifers from different mycorrhizal associations. TREE PHYSIOLOGY 2020; 40:1071-1079. [PMID: 32333786 DOI: 10.1093/treephys/tpaa051] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 03/15/2020] [Accepted: 04/09/2020] [Indexed: 06/11/2023]
Abstract
Plant roots can exude organic compounds into the soil that are useful for plant survival because they can degrade microorganisms around the roots and enhance allelopathy against other plant invasions. We developed a method to collect carbon (C) exudation on a small scale from tree fine roots by C-free filter traps. We quantified total C through root exudation in four conifers from different microbial symbiotic groups (ectomycorrhiza (ECM) and arbuscular mycorrhiza (AM)) in a cool-temperate forest in Japan. We determined the relationship of mass-based exudation rate from three diameter classes (<0.5, 0.5-1.0, and 1.0-2.5 mm) of the intact root system with root traits such as morphological traits including root diameter, specific root length (SRL), specific root area (SRA), root tissue density (RTD) and chemical traits including root nitrogen (N) content and C/N. Across species, the mass-based root exudation rate was found to correlate with diameter, SRA, RTD, N and C/N. When comparing mycorrhizal types, there were significant relationships between the exudation and diameter, SRL, SRA, root N and C/N in ECM species; however, these were not significant in AM species. Our results show that relationships between in situ root exudation and every measured trait of morphology and chemistry were strongly driven by ECM roots and not by AM roots. These differences might explain the fact that ECM roots in this study potentially covaried by optimizing the exudation and root morphology in forest trees, while exudation in AM roots did not change with changes in root morphology. In addition, the contrasting results may be attributable to the effect of degree and position of ECM and AM colonization in fine root system. Differences in fine root exudation relationships to root morphology for the two types of mycorrhizae will help us better understand the underlying mechanisms of belowground C allocation in forest ecosystems.
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Affiliation(s)
- Maiko Akatsuki
- Faculty of Science, Shinshu University, 3-1-1 Asahi, Matsumoto, Nagano, 390-8621, Japan
| | - Naoki Makita
- Faculty of Science, Shinshu University, 3-1-1 Asahi, Matsumoto, Nagano, 390-8621, Japan
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Ataka M, Sun L, Nakaji T, Katayama A, Hiura T. Five-year nitrogen addition affects fine root exudation and its correlation with root respiration in a dominant species, Quercus crispula, of a cool temperate forest, Japan. TREE PHYSIOLOGY 2020; 40:367-376. [PMID: 31976533 DOI: 10.1093/treephys/tpz143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/22/2019] [Accepted: 12/18/2019] [Indexed: 06/10/2023]
Abstract
In forest ecosystems, fine root respiration directly contributes to belowground carbon (C) cycling. Exudation from fine roots indirectly affects C cycling via enhanced microbial decomposition of soil organic matter. Although these root-derived C fluxes are essential components of belowground C cycling, how nitrogen (N) addition affects these fluxes and their correlations remains unclear. In this study, fine root exudation, respiration and chemical/morphological traits were measured in a dominant canopy species, Quercus crispula Blume, found in a cool temperate forest, the Tomakomai Experimental Forest, Hokkaido University, which has undergone 5-year N addition. Soil-dissolved organic carbon (DOC) was also measured in both bulk and rhizosphere soils to evaluate the impact of fine root exudation on soil C cycling. Compared with a control plot with no N treatment, fine roots in the N addition plot exhibited larger diameters and higher N concentrations, but lower specific root lengths and areas. On a root-weight basis, respiration was not different between plots, but exudation was slightly higher under N addition. On a root-area basis, exudation was significantly higher in the N addition plot. Additionally, differences in DOC between rhizosphere and bulk soils were two times higher in the N addition plot than the control plot. Although fine root respiration was positively correlated with exudation in both the control and N addition plots, the ratio of exudation C to respiration C decreased after 5-year N addition. Nitrogen addition also affected absolute C allocation to fine root exudation and changed the C allocation strategy between exudation and respiration fluxes. These findings will help enhance predictions of belowground C allocation and C cycling under N-rich conditions in the future.
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Affiliation(s)
- Mioko Ataka
- Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake Cho, Sakyo District, Kyoto 6068502, Japan
| | - Lijuan Sun
- Institute of Ecology, College of Urban and Environmental Sciences, and Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, 5 Yiheyuan Road, Haidian District, Beijing 100871, China
| | - Tatsuro Nakaji
- Uryu Experimental Forest, Hokkaido University, Moshiri, Uryu 0740741, Japan
| | - Ayumi Katayama
- Kasuya Research Forest, Kyushu University, 394 Sasaguri, Kasuya 8112415, Japan
| | - Tsutom Hiura
- Field Science Center for Northern Biosphere, Hokkaido University, Kita 9, Nishi 9, Kita District, Sapporo 0600809, Japan
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The Case for Digging Deeper: Soil Organic Carbon Storage, Dynamics, and Controls in Our Changing World. SOIL SYSTEMS 2019. [DOI: 10.3390/soilsystems3020028] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Most of our terrestrial carbon (C) storage occurs in soils as organic C derived from living organisms. Therefore, the fate of soil organic C (SOC) in response to changes in climate, land use, and management is of great concern. Here we provide a unified conceptual model for SOC cycling by gathering the available information on SOC sources, dissolved organic C (DOC) dynamics, and soil biogeochemical processes. The evidence suggests that belowground C inputs (from roots and microorganisms) are the dominant source of both SOC and DOC in most ecosystems. Considering our emerging understanding of SOC protection mechanisms and long-term storage, we highlight the present need to sample (often ignored) deeper soil layers. Contrary to long-held biases, deep SOC—which contains most of the global amount and is often hundreds to thousands of years old—is susceptible to decomposition on decadal timescales when the environmental conditions under which it accumulated change. Finally, we discuss the vulnerability of SOC in different soil types and ecosystems globally, as well as identify the need for methodological standardization of SOC quality and quantity analyses. Further study of SOC protection mechanisms and the deep soil biogeochemical environment will provide valuable information about controls on SOC cycling, which in turn may help prioritize C sequestration initiatives and provide key insights into climate-carbon feedbacks.
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