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Cui H, He C, Zheng W, Jiang Z, Yang J. Effects of nitrogen addition on rhizosphere priming: The role of stoichiometric imbalance. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 914:169731. [PMID: 38163589 DOI: 10.1016/j.scitotenv.2023.169731] [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: 06/27/2023] [Revised: 12/24/2023] [Accepted: 12/26/2023] [Indexed: 01/03/2024]
Abstract
Nitrogen (N) input has a significant impact on the availability of carbon (C), nitrogen (N), and phosphorus (P) in the rhizosphere, leading to an imbalanced stoichiometry in microbial demands. This imbalance can result in energy or nutrient limitations, which, in turn, affect C dynamics during plant growth. However, the precise influence of N addition on the C:N:P imbalance ratio and its subsequent effects on rhizosphere priming effects (RPEs) remain unclear. To address this gap, we conducted a 75-day microcosm experiment, varying N addition rates (0, 150, 300 kg N ha-1), to examine how microbes regulate RPE by adapting to stoichiometry and maintaining homeostasis in response to N addition, using the 13C natural method. Our result showed that N input induced a stoichiometric imbalance in C:N:P, leading to P or C limitation for microbes during plant growth. Microbes responded by adjusting enzymatic stoichiometry and functional taxa to preserve homeostasis, thereby modifying the threshold element ratios (TERs) to cope with the C:N:P imbalance. Microbes adapted to the stoichiometric imbalance by reducing TER, which was attributed to a reduction in carbon use efficiency. Consequently, we observed higher RPE under P limitation, whereas the opposite trend was observed under C or N limitation. These results offer novel insights into the microbial regulation of RPE variation under different soil nutrient conditions and contribute to a better understanding of soil C dynamics.
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Affiliation(s)
- Hao Cui
- Institute of Environment Pollution Control and Treatment, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Chao He
- Institute of Environment Pollution Control and Treatment, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Weiwei Zheng
- Institute of Environment Pollution Control and Treatment, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Zhenhui Jiang
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, Zhejiang, China.
| | - Jingping Yang
- Institute of Environment Pollution Control and Treatment, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China.
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Yu Z, Zhang C, Liu X, Lei J, Zhang Q, Yuan Z, Peng C, Koerner SE, Xu J, Guo L. Responses of C:N:P stoichiometric correlations among plants, soils and microorganisms to warming: A meta-analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168827. [PMID: 38030014 DOI: 10.1016/j.scitotenv.2023.168827] [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: 08/01/2023] [Revised: 11/21/2023] [Accepted: 11/22/2023] [Indexed: 12/01/2023]
Abstract
Plants, soils and microorganisms play important roles in maintaining stable terrestrial stoichiometry. Studying how nutrient balances of these biotic and abiotic players vary across temperature gradients is important when predicting ecosystem changes on a warming planet. The respective responses of plant, soil and microbial stoichiometric ratios to warming have been observed, however, whether and how the stoichiometric correlations among the three components shift under warming has not been clearly understood and identified. In the present study, we have performed a meta-analysis based on 600 case studies from 74 sites or locations to clarify whether and how warming affects plant, soil and microbial stoichiometry, respectively, and their correlations. Our results indicated that: (1) globally, plants had higher C:N and C:P values compared to soil and microbial pools, but their N:P distributions were similar; (2) warming did not significantly alter plant, soil and microbial C:N and C:P values, but had a noticeable effect on plant N:P ratios. When ecosystem types, duration and magnitude of warming were taken into account, there was an inconsistent and even inverse warming response in terms of the direction and magnitude of changes in the C:N:P ratios occurring among plants, soils and microorganisms; (3) despite various warming responses of the stoichiometric ratios detected separately for plants, soils and microorganisms, the stoichiometric correlations among all three parts remained constant even under different warming scenarios. Our study highlighted the complexity of the effect of warming on the C:N:P stoichiometry, as well as the absence and importance of simultaneous measurements of stoichiometric ratios across different components of terrestrial ecosystems, which should be urgently strengthened in future studies.
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Affiliation(s)
- Zongkai Yu
- College of Grassland Agriculture, Northwest A&F University, Yangling 712100, China
| | - Chao Zhang
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling 712100, China
| | - Xiaowei Liu
- College of Grassland Agriculture, Northwest A&F University, Yangling 712100, China
| | - Jichu Lei
- The Research Center of Soil and Water Conservation and Ecological Environment, Chinese Academy of Sciences and Ministry of Education, Yangling 712100, China; Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiang Zhang
- College of Grassland Agriculture, Northwest A&F University, Yangling 712100, China
| | - Zhiyou Yuan
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling 712100, China
| | - Changhui Peng
- School of Geographic Sciences, Hunan Normal University, Changsha 410081, China; Department of Biology Science, Institute of Environment Sciences, University of Quebec at Montreal, H3C 3P8, Canada
| | - Sally E Koerner
- Department of Biology, University of North Carolina at Greensboro, Greensboro 27402, USA
| | - Jianchu Xu
- Center for Mountain Ecosystem Studies, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; World Agroforestry Center, Nairobi 00100, Kenya
| | - Liang Guo
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling 712100, China; Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, China.
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3
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Raza T, Qadir MF, Khan KS, Eash NS, Yousuf M, Chatterjee S, Manzoor R, Rehman SU, Oetting JN. Unrevealing the potential of microbes in decomposition of organic matter and release of carbon in the ecosystem. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 344:118529. [PMID: 37418912 DOI: 10.1016/j.jenvman.2023.118529] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 06/13/2023] [Accepted: 06/25/2023] [Indexed: 07/09/2023]
Abstract
Organic matter decomposition is a biochemical process with consequences affecting climate change and ecosystem productivity. Once decomposition begins, C is lost as CO2 or sequestered into more recalcitrant carbon difficult to further degradation. As microbial respiration releases carbon dioxide into the atmosphere, microbes act as gatekeepers in the whole process. Microbial activities were found to be the second largest CO2 emission source in the environment after human activities (industrialization), and research investigations suggest that this may have affected climate change over the past few decades. It is crucial to note that microbes are major contributors in the whole C cycle (decomposition, transformation, and stabilization). Therefore, imbalances in the C cycle might be causing changes in the entire carbon content of the ecosystem. The significance of microbes, especially soil bacteria in the terrestrial carbon cycle requires more attention. This review focuses on the factors that affect microorganism behavior during the breakdown of organic materials. The key factors affecting the microbial degradation processes are the quality of the input material, nitrogen, temperature, and moisture content. In this review, we suggest that to address global climate change and its effects on agricultural systems and vice versa, there is a need to double-up on efforts and conduct new research studies to further evaluate the potential of microbial communities to reduce their contribution to terrestrial carbon emission.
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Affiliation(s)
- Taqi Raza
- The Biosystems Engineering & Soil Science, University of Tennessee, Knoxville, USA.
| | - Muhammad Farhan Qadir
- Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad 38040, Pakistan
| | - Khuram Shehzad Khan
- College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, China Agricultural University, Beijing 100193, China
| | - Neal S Eash
- The Biosystems Engineering & Soil Science, University of Tennessee, Knoxville, USA
| | - Muhammad Yousuf
- Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad 38040, Pakistan
| | - Sumanta Chatterjee
- USDA ARS, Hydrology and Remote Sensing Laboratory, 10300 Baltimore Avenue, Beltsville, MD 20705, USA; ICAR-National Rice Research Institute, Cuttack 753006, India
| | - Rabia Manzoor
- Land Resources Research Institute, National Agricultural Research Centre, Islamabad, Pakistan
| | - Sana Ur Rehman
- National Research Center of Intercropping, The Islamia University of Bahawalpur, Pakistan
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Qu Q, Wang Z, Gan Q, Liu R, Xu H. Impact of drought on soil microbial biomass and extracellular enzyme activity. FRONTIERS IN PLANT SCIENCE 2023; 14:1221288. [PMID: 37692424 PMCID: PMC10491016 DOI: 10.3389/fpls.2023.1221288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 08/09/2023] [Indexed: 09/12/2023]
Abstract
Introduction With the continuous changes in climate patterns due to global warming, drought has become an important limiting factor in the development of terrestrial ecosystems. However, a comprehensive understanding of the impact of drought on soil microbial activity at a global scale is lacking. Methods In this study, we aimed to examine the effects of drought on soil microbial biomass (carbon [MBC], nitrogen [MBN], and phosphorus [MBP]) and enzyme activity (β-1, 4-glucosidase [BG]; β-D-cellobiosidase [CBH]; β-1, 4-N-acetylglucosaminidase [NAG]; L-leucine aminopeptidase [LAP]; and acid phosphatase [AP]). Additionally, we conducted a meta-analysis to determine the degree to which these effects are regulated by vegetation type, drought intensity, drought duration, and mean annual temperature (MAT). Result and discussion Our results showed that drought significantly decreased the MBC, MBN, and MBP and the activity levels of BG and AP by 22.7%, 21.2%, 21.6%, 26.8%, and 16.1%, respectively. In terms of vegetation type, drought mainly affected the MBC and MBN in croplands and grasslands. Furthermore, the response ratio of BG, CBH, NAG, and LAP were negatively correlated with drought intensity, whereas MBN and MBP and the activity levels of BG and CBH were negatively correlated with drought duration. Additionally, the response ratio of BG and NAG were negatively correlated with MAT. In conclusion, drought significantly reduced soil microbial biomass and enzyme activity on a global scale. Our results highlight the strong impact of drought on soil microbial biomass and carbon- and phosphorus-acquiring enzyme activity.
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Affiliation(s)
- Qing Qu
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwestern China, Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in Northwestern China of Ministry of Education, Ningxia University, Yinchuan, China
- Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, China
| | - Zhen Wang
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwestern China, Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in Northwestern China of Ministry of Education, Ningxia University, Yinchuan, China
| | - Quan Gan
- College of Forestry, Sichuan Agricultural University, Chengdu, China
| | - Rentao Liu
- Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwestern China, Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in Northwestern China of Ministry of Education, Ningxia University, Yinchuan, China
| | - Hongwei Xu
- College of Forestry, Sichuan Agricultural University, Chengdu, China
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Andrews HM, Krichels AH, Homyak PM, Piper S, Aronson EL, Botthoff J, Greene AC, Jenerette GD. Wetting-induced soil CO 2 emission pulses are driven by interactions among soil temperature, carbon, and nitrogen limitation in the Colorado Desert. GLOBAL CHANGE BIOLOGY 2023; 29:3205-3220. [PMID: 36907979 DOI: 10.1111/gcb.16669] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 01/20/2023] [Indexed: 05/03/2023]
Abstract
Warming-induced changes in precipitation regimes, coupled with anthropogenically enhanced nitrogen (N) deposition, are likely to increase the prevalence, duration, and magnitude of soil respiration pulses following wetting via interactions among temperature and carbon (C) and N availability. Quantifying the importance of these interactive controls on soil respiration is a key challenge as pulses can be large terrestrial sources of atmospheric carbon dioxide (CO2 ) over comparatively short timescales. Using an automated sensor system, we measured soil CO2 flux dynamics in the Colorado Desert-a system characterized by pronounced transitions from dry-to-wet soil conditions-through a multi-year series of experimental wetting campaigns. Experimental manipulations included combinations of C and N additions across a range of ambient temperatures and across five sites varying in atmospheric N deposition. We found soil CO2 pulses following wetting were highly predictable from peak instantaneous CO2 flux measurements. CO2 pulses consistently increased with temperature, and temperature at time of wetting positively correlated to CO2 pulse magnitude. Experimentally adding N along the N deposition gradient generated contrasting pulse responses: adding N increased CO2 pulses in low N deposition sites, whereas adding N decreased CO2 pulses in high N deposition sites. At a low N deposition site, simultaneous additions of C and N during wetting led to the highest observed soil CO2 fluxes reported globally at 299.5 μmol CO2 m-2 s-1 . Our results suggest that soils have the capacity to emit high amounts of CO2 within small timeframes following infrequent wetting, and pulse sizes reflect a non-linear combination of soil resource and temperature interactions. Importantly, the largest soil CO2 emissions occurred when multiple resources were amended simultaneously in historically resource-limited desert soils, pointing to regions experiencing simultaneous effects of desertification and urbanization as key locations in future global C balance.
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Affiliation(s)
- Holly M Andrews
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, California, USA
| | - Alexander H Krichels
- Department of Environmental Sciences, University of California, Riverside, California, USA
- Center for Conservation Biology, University of California, Riverside, California, USA
| | - Peter M Homyak
- Department of Environmental Sciences, University of California, Riverside, California, USA
| | - Stephanie Piper
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA
| | - Emma L Aronson
- Department of Microbiology and Plant Pathology, University of California, Riverside, California, USA
| | - Jon Botthoff
- Center for Conservation Biology, University of California, Riverside, California, USA
| | - Aral C Greene
- Department of Environmental Sciences, University of California, Riverside, California, USA
| | - G Darrel Jenerette
- Center for Conservation Biology, University of California, Riverside, California, USA
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA
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6
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Zeng W, Wang Z, Chen X, Yao X, Ma Z, Wang W. Nitrogen deficiency accelerates soil organic carbon decomposition in temperate degraded grasslands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 881:163424. [PMID: 37054788 DOI: 10.1016/j.scitotenv.2023.163424] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 03/24/2023] [Accepted: 04/06/2023] [Indexed: 04/15/2023]
Abstract
The impacts of nitrogen (N) availability on soil organic carbon (SOC) decomposition were often explored based on N enrichment (N+) experiments. However, many natural and anthropogenic processes often reduce soil N availability. There is no direct evidence about how decreased N availability (N-) affects SOC decomposition, and the mechanisms of microbe-driven SOC decomposition in response to N availability remain unclear. Here, we used ion-exchange membranes to simulate N-. Soil samples from four temperate grassland sites, ranging from non-degradation to extreme degradation, were incubated with the N- and N+ treatments. We found that the total cumulative carbon (C) release was promoted by the N- treatment (8.60 to 87.30 mg C/g Cinital) but was inhibited by the N+ treatment (-129.81 to -16.49 mg C/g Cinital), regardless of the degradation status. N- dramatically increased recalcitrant C decomposition by increasing soil pH at all grassland sites; while did not affect or even decreased labile C decomposition by significantly increasing microbial C use efficiency and soil microbial biomass N. Interestingly, the effects of N- and N+ on SOC decomposition was asymmetric; with increased grassland degradation, the SOC decomposition was more sensitive to N- than to N+. Our results provide direct evidence for the different effects and mechanisms of N- on SOC decomposition and should be considered in soil process models to better predict the response of the nutrient cycle to global change.
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Affiliation(s)
- Wenjing Zeng
- Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China; Department of Ecology, College of Urban and Environmental Sciences, Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China
| | - Zhaodi Wang
- Department of Ecology, College of Urban and Environmental Sciences, Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China
| | - Xinyue Chen
- Department of Ecology, College of Urban and Environmental Sciences, Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China
| | - Xiaodong Yao
- Department of Ecology, College of Urban and Environmental Sciences, Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China; State Key Laboratory for Subtropical Mountain Ecology of the Ministry of Science and Technology and Fujian Province, School of Geographical Sciences, Fujian Normal University, Fuzhou, China
| | - Zeqing Ma
- Qianyanzhou Ecological Research Station, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Wei Wang
- Department of Ecology, College of Urban and Environmental Sciences, Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China.
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7
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Zuccarini P, Sardans J, Asensio L, Peñuelas J. Altered activities of extracellular soil enzymes by the interacting global environmental changes. GLOBAL CHANGE BIOLOGY 2023; 29:2067-2091. [PMID: 36655298 DOI: 10.1111/gcb.16604] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 12/14/2022] [Indexed: 05/28/2023]
Abstract
Soil enzymes are crucial in mediating ecosystems' responses to environmental drivers, so that the comprehension of their sensitivity to drivers of global change can help make predictions of future scenarios and design tailored interventions of biomanipulation. Drivers of global change usually act in combination of two or more, and indirect effects of one driver acting through modification of another one often occur, yet most of both manipulative and meta-analysis studies available tend to focus on the direct effect of one single driver on the activity of specific soil enzymes. One of the biggest challenges is, therefore, represented by the difficulty in assessing the interactions between different drivers, due to the complexity of disentangling the single direct effects from the indirect and combined ones. In this review, after elucidating the general mechanisms of soil enzyme production and activity regulation, we display the state-of-the-art knowledge on direct, indirect and combined effects of the main drivers of global change on soil enzyme activities, identify gaps in knowledge and challenges from research, plus we analyse how this can reverberate in the future of biomanipulation techniques for the improvement of ecosystem services. We conclude that qualitative but not quantitative outcomes can be predicted for some interactions such as warming + drought or warming + CO2 , while for other ones, the results are controversial: future basic research will have to center on this holistic approach. A general trend toward the overall increase of soil enzyme activities and acceleration of biogeochemical cycles will persist, until an inflection will be caused by factors such as future shifts in microbial communities and changes in carbon use efficiency. Applied research will develop toward the refinement of "in situ" analytical systems for the study of soil enzyme activities and the support of bioengineering for the better tailoring of interventions of biomanipulation.
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Zhang S, Bai J, Zhang G, Xia Z, Wu M, Lu H. Negative effects of soil warming, and adaptive cultivation strategies of maize: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 862:160738. [PMID: 36496024 DOI: 10.1016/j.scitotenv.2022.160738] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 11/24/2022] [Accepted: 12/03/2022] [Indexed: 06/17/2023]
Abstract
Temperature is a key factor in regulating and controlling several ecological processes. As there is a feedback relationship between many biogeochemical processes and climate change, their response to temperature changes is particularly important. Previously, a large volume of literature has extensively explored the impact of rising air temperature on shoot growth and maize yield, from enzymatic responses within the leaf to grain yield. As the global temperature continues to increase and the frequency, duration, and/or intensity of heat wave events increases, the soil temperature of the tilth is likely to rise sharply. As one of the most widely planted food crops in the world, maize may be subjected to additional soil temperature pressure. However, as a nutrient organ in direct contact with soil, the root plays a key role in adapting the whole plant to excessive soil temperature. Little research has been done on the effect of the soil microenvironment induced by higher soil temperature on maize root growth and root to shoot communication regulation. Therefore, this review summarizes (1) the effects of excessive soil temperature on the soil microenvironment, including soil respiration, microbial community composition, carbon mineralization, and enzyme activity; (2) the negative response of absorption of water and nutrients by roots and maize root-shoot growth to excessive soil temperature; and (3) potential cultivation strategies to improve maize yield, including improving tillage methods, adding biochar amendments, applying organic fertilizers, optimizing irrigation, and farmland mulching.
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Affiliation(s)
- Shibo Zhang
- College of Agronomy, Northwest A&F University, Yangling 712100, China; Key Laboratory of Biology and Genetic Improvement of Maize in Arid Area of Northwest Region, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Jingxuan Bai
- College of Agronomy, Northwest A&F University, Yangling 712100, China; Key Laboratory of Biology and Genetic Improvement of Maize in Arid Area of Northwest Region, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Guixin Zhang
- College of Agronomy, Northwest A&F University, Yangling 712100, China; Key Laboratory of Biology and Genetic Improvement of Maize in Arid Area of Northwest Region, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Zhenqing Xia
- College of Agronomy, Northwest A&F University, Yangling 712100, China; Key Laboratory of Biology and Genetic Improvement of Maize in Arid Area of Northwest Region, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Mengke Wu
- College of Agronomy, Northwest A&F University, Yangling 712100, China; Key Laboratory of Biology and Genetic Improvement of Maize in Arid Area of Northwest Region, Ministry of Agriculture and Rural Affairs, Yangling 712100, China
| | - Haidong Lu
- College of Agronomy, Northwest A&F University, Yangling 712100, China; Key Laboratory of Biology and Genetic Improvement of Maize in Arid Area of Northwest Region, Ministry of Agriculture and Rural Affairs, Yangling 712100, China.
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Zhang Y, Li JT, Xu X, Chen HY, Zhu T, Xu JJ, Xu XN, Li JQ, Liang C, Li B, Fang CM, Nie M. Temperature fluctuation promotes the thermal adaptation of soil microbial respiration. Nat Ecol Evol 2023; 7:205-213. [PMID: 36635341 DOI: 10.1038/s41559-022-01944-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 10/25/2022] [Indexed: 01/14/2023]
Abstract
The magnitude of the feedback between soil microbial respiration and increased mean temperature may decrease (a process called thermal adaptation) or increase over time, and accurately representing this feedback in models improves predictions of soil carbon loss rates. However, climate change entails changes not only in mean temperature but also in temperature fluctuation, and how this fluctuation regulates the thermal response of microbial respiration has never been systematically evaluated. By analysing subtropical forest soils from a 2,000 km transect across China, we showed that although a positive relationship between soil microbial biomass-specific respiration and temperature was observed under increased constant incubation temperature, an increasing temperature fluctuation had a stronger negative effect. Our results further indicated that changes in bacterial community composition and reduced activities of carbon degradation enzymes promoted the effect of temperature fluctuation. This adaptive response of soil microbial respiration suggests that climate warming may have a lesser exacerbating effect on atmospheric CO2 concentrations than predicted.
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Affiliation(s)
- Yan Zhang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
| | - Jin-Tao Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
| | - Xiao Xu
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology and Centre for Invasion Biology, Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming, China
| | - Hong-Yang Chen
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
- Research Center for Northeast Asia Carbon Sink, Center for Ecological Research, Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, China
| | - Ting Zhu
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
| | - Jian-Jun Xu
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
| | - Xiao-Ni Xu
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
| | - Jin-Quan Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
| | - Chao Liang
- Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Bo Li
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
- Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology and Centre for Invasion Biology, Institute of Biodiversity, School of Ecology and Environmental Science, Yunnan University, Kunming, China
| | - Chang-Ming Fang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China
| | - Ming Nie
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary, Institute of Eco-Chongming, School of Life Sciences, Fudan University, Shanghai, China.
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10
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Effects of long-term enclosing on distributions of carbon and nitrogen in semia-arid grassland of Inner Mongolia. ECOL INFORM 2022. [DOI: 10.1016/j.ecoinf.2022.101762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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11
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Johnson DC, Teague R, Apfelbaum S, Thompson R, Byck P. Adaptive multi-paddock grazing management's influence on soil food web community structure for: increasing pasture forage production, soil organic carbon, and reducing soil respiration rates in southeastern USA ranches. PeerJ 2022; 10:e13750. [PMID: 35873909 PMCID: PMC9306548 DOI: 10.7717/peerj.13750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 06/28/2022] [Indexed: 01/17/2023] Open
Abstract
Background Measurement of two grazing management's influence on pasture productivity, soil food web structure, soil organic carbon and soil microbial respiration efficiency was conducted on five southeastern US, across-the-fence ranch pairs to compare adaptive multi-paddock grazing (AMP) management, using short grazing events with planned, adaptive recovery periods, to conventional grazing (CG) management, with continuous grazing at low stock density. Methodology A point-in-time experimental field analysis was conducted to compare five AMP or CG ranch pairs to better understand the influence of grazing management on (a) standing crop biomass productivity; (b) soil food web community population, structure and functionality; (c) soil organic carbon accrual; and d) soil-C (CO2) respiration kinetics. Results AMP grazing systems outperformed CG systems by generating: (a) 92.68 g m-2 more standing crop biomass (SCB), promoting 46% higher pasture photosynthetic capacity (Two sample Mann-Whitney; Z = 6.1836; no DF in MW; p = 6.26 × 10-10; Effect size = 0.35) (b) a strong positive linear relationship of SCB with fungal biomass (R = 0.9915; F(1,3) = 175.35; p = 0.015); fungal to bacterial (F:B) biomass ratio (R = 0.9616; F(1,3) = 36.75; p = 0.009) and a soil food web proxy (R = 0.9616; F(1,3) = 36.75; p = 0.009) and a concurrent very strong inverse relationship with bacteria biomass (R = -0.946; F(1,3) = 25.56; p = 0.015); (c) significant predator/prey interactions with an inverse relationship with bacterial population biomass (R = - 0.946; F(1,3) = 25.56; p = 0.015) and a positive relationship with total protozoa enumeration (R = 0.9826; F(1,3) = 83.68; p = 0.003) when compared to SCB; (d) a 19.52% reduction in soil C (CO2) respiration rates (Two sample t-test; T = -2.3581; DF = 52.3541; p = 0.0221; Effect size = 0.59); and (e) a 20.6% increase in soil organic carbon (SOC) in the top 10 cm of soil profile (Two sample Mann-Whitney; Z = 2.6507; no DF in MW; p = 0.008; Effect size = 0.24). Rancher conversion to AMP grazing strategies would appear to regenerate soil food web population, structure, diversity and biological functionality helping to improve: carbon flow into plant biomass, buildup of soil carbon, predator/prey nutrient cycling and soil microbial respiration efficiency while offering improved climate resilience and a strategy to increase the capture and storage of atmospheric CO2 in soils of the world's rangeland.
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Affiliation(s)
- David C. Johnson
- Civil Engineering, College of Engineering, New Mexico State University, Las Cruces, NM, United States of America
| | - Richard Teague
- AgriLife Research, Texas A&M University, Vernon, TX, United States of America,Department of Rangeland, Wildlife and Fisheries Management, Texas A&M University, College Station, TX, United States of America
| | - Steven Apfelbaum
- Applied Ecological Institute, Inc., Juda, WI, United States of America
| | - Ry Thompson
- Resource Environmental Solutions, Broadhead, WI, United States of America
| | - Peter Byck
- School of Sustainability, Arizona State University, Tempe, AZ, United States of America,Walter Cronkite School of Journalism, Arizona State University, Phoenix, AZ, United States of America
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12
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Schedlbauer JL, Miller J. Edge effects increase soil respiration without altering soil carbon stocks in temperate broadleaf forests. Ecosphere 2022. [DOI: 10.1002/ecs2.4092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
| | - Jason Miller
- Department of Biology West Chester University West Chester Pennsylvania USA
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13
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Cabrerizo MJ, Medina-Sánchez JM, González-Olalla JM, Sánchez-Gómez D, Carrillo P. Microbial plankton responses to multiple environmental drivers in marine ecosystems with different phosphorus limitation degrees. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 816:151491. [PMID: 34752863 DOI: 10.1016/j.scitotenv.2021.151491] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 10/21/2021] [Accepted: 11/03/2021] [Indexed: 06/13/2023]
Abstract
Multiple drivers are threatening the functioning of the microbial food webs and trophic interactions. Our understanding about how temperature, CO2, nutrient inputs, and solar ultraviolet radiation (UVR) availability interact to alter ecosystem functioning is scarce because research has focused on single and double interactions. Moreover, the role that the degree of in situ nutrient limitation could play in the outcome of these interactions has been largely neglected, despite it is predominant in marine ecosystems. We address these uncertainties by combining remote-sensing analyses, and a collapsed experimental design with natural microbial communities from Mediterranean Sea and Atlantic Ocean exposed to temperature, nutrients, CO2, and UVR interactions. At the decade scale, we found that more intense and frequent (and longer lasting) Saharan dust inputs (and marine heatwaves) were only coupled with reduced phytoplankton biomass production. When microbial communities were concurrently exposed to future temperature, CO2, nutrient, and UVR conditions (i.e. the drivers studied over long-term scales), we found shifts from net autotrophy [primary production:respiration (PP:R) ratio > 1] towards a metabolic equilibrium (PP:R ratio ~ 1) or even a net heterotrophy (PP:R ratio < 1), as P-limitation degree was higher (i.e. Atlantic Ocean). These changes in the metabolic balance were coupled with a weakened phytoplankton-bacteria interaction (i.e. bacterial carbon demand exceeded phytoplankton carbon supply. Our work reveals that an accentuated in situ P limitation may promote reductions both in carbon uptake and fluxes between trophic levels in microbial plankton communities under global-change conditions. We show that considering long-term series can aid in identifying major local environmental drivers (i.e. temperature and nutrients in our case), easing the design of future global-change studies, but also that the abiotic environment to which microbial plankton communities are acclimated should be taken into account to avoid biased predictions concerning the effects of multiple interacting global-change drivers on marine ecosystems.
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Affiliation(s)
- Marco J Cabrerizo
- Departamento de Ecología y Biología Animal, Facultad de Ciencias del Mar, Universidad de Vigo, Campus Lagoas Marcosende s/n, 36310 Vigo, Spain; Centro de Investigación Mariña, Universidad de Vigo (CIM-UVigo), Illa de Toralla s/n, 36331 Vigo, Spain; Departamento de Ecología, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain.
| | - Juan Manuel Medina-Sánchez
- Departamento de Ecología, Universidad de Granada, Campus Fuentenueva s/n, 18071 Granada, Spain; Instituto Universitario de Investigación del Agua, C/Ramón y Cajal, n 4, 18071 Granada, Spain
| | | | - Daniel Sánchez-Gómez
- Instituto Universitario de Investigación del Agua, C/Ramón y Cajal, n 4, 18071 Granada, Spain
| | - Presentación Carrillo
- Instituto Universitario de Investigación del Agua, C/Ramón y Cajal, n 4, 18071 Granada, Spain
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14
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Souza LFT, Billings SA. Temperature and pH mediate stoichiometric constraints of organically derived soil nutrients. GLOBAL CHANGE BIOLOGY 2022; 28:1630-1642. [PMID: 34767675 PMCID: PMC9298831 DOI: 10.1111/gcb.15985] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 10/27/2021] [Indexed: 06/13/2023]
Abstract
It remains unclear how warming will affect resource flows during soil organic matter (SOM) decomposition, in part due to uncertainty in how exoenzymes produced by microbes and roots will function. Rising temperatures can enhance the activity of most exoenzymes, but soil pH can impose limitations on their catalytic efficiency. The effects of temperature and pH on enzyme activity are often examined in environmental samples, but purified enzyme kinetics reveal fundamental attributes of enzymes' intrinsic temperature responses and how relative release of decay-liberated resources (their flow ratios) can change with environmental conditions. In this paper, we illuminate the principle that fundamental, biochemical limitations on SOM release of C, N, and P during decay, and differential exoenzymes' responses to the environment, can exert biosphere-scale significance on the stoichiometry of bioavailable soil resources. To that end, we combined previously published intrinsic temperature sensitivities of two hydrolytic enzymes that release C and N during decay with a novel data set characterizing the kinetics of a P-releasing enzyme (acid phosphatase) across an ecologically relevant pH gradient. We use these data to estimate potential change in the flow ratios derived from these three enzymes' activities (C:N, C:P, and N:P) at the global scale by the end of the century, based on temperature projections and soil pH distribution. Our results highlight how the temperature sensitivity of these hydrolytic enzymes and the influence of pH on that sensitivity can govern the relative availability of bioavailable resources derived from these enzymes. The work illuminates the utility of weaving well-defined kinetic constraints of microbes' exoenzymes into models that incorporate changing SOM inputs and composition, nutrient availability, and microbial functioning into their efforts to project terrestrial ecosystem functioning in a changing climate.
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Affiliation(s)
- Ligia F. T. Souza
- Department of Ecology and Evolutionary BiologyKansas Biological Survey & Center for Ecological ResearchUniversity of KansasLawrenceKansasUSA
| | - Sharon A. Billings
- Department of Ecology and Evolutionary BiologyKansas Biological Survey & Center for Ecological ResearchUniversity of KansasLawrenceKansasUSA
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15
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McLaren JR, Buckeridge KM. Enhanced plant leaf P and unchanged soil P stocks after a quarter century of warming in the arctic tundra. Ecosphere 2021. [DOI: 10.1002/ecs2.3838] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Jennie R. McLaren
- Department of Biological Sciences University of Texas at El Paso El Paso Texas 79968 USA
| | - Kate M. Buckeridge
- Department of Environmental Research and Innovation (ERIN) Luxembourg Institute of Science and Technology (LIST) 41 Rue du Brill 4422 Belvaux Luxembourg
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16
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Gao XL, Li X, Zhao L, Kuzyakov Y. Shrubs magnify soil phosphorus depletion in Tibetan meadows: Conclusions from C:N:P stoichiometry and deep soil profiles. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 785:147320. [PMID: 33957589 DOI: 10.1016/j.scitotenv.2021.147320] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 04/19/2021] [Accepted: 04/19/2021] [Indexed: 05/22/2023]
Abstract
Globally, the proliferation of shrubs within grasslands stimulates soil phosphorus (P) cycling and increases topsoil P storage beneath their canopies. However, little is known regarding the impact of shrub encroachment on subsoil P storage, and whether shrubs mediate changes in soil stoichiometry, like increasing P cycling. In grazed meadows on the Tibetan Plateau, soil and roots were sampled to 1 m depth in shrubby Hippophae rhamnoides ssp. sinensis groves and the surrounding grassy areas. Shrubs had higher P content than grasses, but lower C:P ratios in their leaves, litter, and roots. Similarly, shrubs had higher microbial P content than grasses, but lower microbial biomass C:P and N:P ratios in the soil. The larger microbial P stock in the 1 m of soil beneath shrubs responded to the larger root P stock there as well. Thus, both the plants and microbes acquired more P in shrubby areas than in grassy areas by accelerating P mineralization. The greater net production of available P in the topsoil and the synthesis of microbial P throughout the profile under shrubs increased the P solubility. Total P, inorganic P, and organic P stocks were lower under shrubs than under grasses in the top 1 m of soil. This decrease in soil P storage beneath shrubs is most likely attributable to P leaching due to higher P solubility, heavy rainfall, and larger soil gaps. Moreover, shrubs also had larger plant biomass P stock compared to grasses, and thus the depletion of P from the top 1 m of soil was further magnified via plant biomass removal. We concluded that shrubs increase P cycling to overcome the stoichiometric imbalance between their P requirement and the supply in the soil, and the fast P cycling under shrubs magnify P depletion within the rooted soil depth in alpine meadows.
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Affiliation(s)
- Xiao-Li Gao
- State Key Laboratory of Grassland and Agro-ecosystems, School of Life Sciences, Lanzhou University, 222 South Tianshui Road, Lanzhou 730000, China; Henan Key Laboratory of Integrated Air Pollution Control and Ecological Security, Henan University, Kaifeng, Jinming Avenue, Henan 475004, China.
| | - Xiaogang Li
- State Key Laboratory of Grassland and Agro-ecosystems, School of Life Sciences, Lanzhou University, 222 South Tianshui Road, Lanzhou 730000, China
| | - Ling Zhao
- State Key Laboratory of Grassland and Agro-ecosystems, School of Life Sciences, Lanzhou University, 222 South Tianshui Road, Lanzhou 730000, China
| | - Yakov Kuzyakov
- Department of Soil Science of Temperate Ecosystems, Department of Agricultural Soil Science, University of Göttingen, Göttingen, Germany
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17
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Metabolic capabilities mute positive response to direct and indirect impacts of warming throughout the soil profile. Nat Commun 2021; 12:2089. [PMID: 33828081 PMCID: PMC8027381 DOI: 10.1038/s41467-021-22408-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 03/10/2021] [Indexed: 02/01/2023] Open
Abstract
Increasing global temperatures are predicted to stimulate soil microbial respiration. The direct and indirect impacts of warming on soil microbes, nevertheless, remain unclear. This is particularly true for understudied subsoil microbes. Here, we show that 4.5 years of whole-profile soil warming in a temperate mixed forest results in altered microbial community composition and metabolism in surface soils, partly due to carbon limitation. However, microbial communities in the subsoil responded differently to warming than in the surface. Throughout the soil profile-but to a greater extent in the subsoil-physiologic and genomic measurements show that phylogenetically different microbes could utilize complex organic compounds, dampening the effect of altered resource availability induced by warming. We find subsoil microbes had 20% lower carbon use efficiencies and 47% lower growth rates compared to surface soils, which constrain microbial communities. Collectively, our results show that unlike in surface soils, elevated microbial respiration in subsoils may continue without microbial community change in the near-term.
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18
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Liu F, Kou D, Chen Y, Xue K, Ernakovich JG, Chen L, Yang G, Yang Y. Altered microbial structure and function after thermokarst formation. GLOBAL CHANGE BIOLOGY 2021; 27:823-835. [PMID: 33155741 DOI: 10.1111/gcb.15438] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 10/05/2020] [Indexed: 05/27/2023]
Abstract
Permafrost thaw could induce substantial carbon (C) emissions to the atmosphere, and thus trigger a positive feedback to climate warming. As the engine of biogeochemical cycling, soil microorganisms exert a critical role in mediating the direction and strength of permafrost C-climate feedback. However, our understanding about the impacts of thermokarst (abrupt permafrost thaw) on microbial structure and function remains limited. Here we employed metagenomic sequencing to analyze changes in topsoil (0-15 cm) microbial communities and functional genes along a permafrost thaw sequence (1, 10, and 16 years since permafrost collapse) on the Tibetan Plateau. By combining laboratory incubation and a two-pool model, we then explored changes in soil labile and stable C decomposition along the thaw sequence. Our results showed that topsoil microbial α-diversity decreased, while the community structure and functional gene abundance did not exhibit any significant change at the early stage of collapse (1 year since collapse) relative to non-collapsed control. However, as the time since the collapse increased, both the topsoil microbial community structure and functional genes differed from the control. Abundances of functional genes involved in labile C degradation decreased while those for stable C degradation increased at the late stage of collapse (16 years since collapse), largely driven by changes in substrate properties along the thaw sequence. Accordingly, faster stable C decomposition occurred at the late stage of collapse compared to the control, which was associated with the increase in relative abundance of functional genes for stable C degradation. These results suggest that upland thermokarst alters microbial structure and function, particularly enhances soil stable C decomposition by modulating microbial functional genes, which could reinforce a warmer climate over the decadal timescale.
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Affiliation(s)
- Futing Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
- Key Laboratory of Tree Breeding and Cultivation of the State Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China
| | - Dan Kou
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Yongliang Chen
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Kai Xue
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Jessica G Ernakovich
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH, USA
| | - Leiyi Chen
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Guibiao Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Yuanhe Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
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19
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Root Litter Mixing with That of Japanese Cedar Altered CO2 Emissions from Moso Bamboo Forest Soil. FORESTS 2020. [DOI: 10.3390/f11030356] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Research Highlights: This study examined the effect of mixing fine roots of Japanese cedar with moso bamboo on soil carbon dioxide (CO2) emissions with nitrogen (N) addition treatment. Background and Objectives: Moso bamboo expansion into adjacent forests and N deposition are common in subtropical China. The effects of litter input on soil CO2 emissions, especially fine root litter input, are crucial to evaluate contribution of moso bamboo expansion on greenhouse gas emissions. Materials and Methods: An in situ study over 12 months was conducted to examine mixing fine roots of Japanese cedar with moso bamboo on soil CO2 emissions with simulated N deposition. Results: Fine root litter input of Japanese cedar and moso bamboo both impacted soil CO2 emission rates, with mixed litter, positively impact soil CO2 emission rate with N addition treatment. Moso bamboo fine root litter input decreased the sensitivity of soil CO2 emission rate to soil temperature. Conclusions: The encroachment of moso bamboo into adjacent forests might benefit soil C sequestration under warming climate, which will also benefit the mitigation of global climate change.
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20
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Mueller P, Granse D, Nolte S, Weingartner M, Hoth S, Jensen K. Unrecognized controls on microbial functioning in Blue Carbon ecosystems: The role of mineral enzyme stabilization and allochthonous substrate supply. Ecol Evol 2020; 10:998-1011. [PMID: 32015860 PMCID: PMC6988540 DOI: 10.1002/ece3.5962] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 11/11/2019] [Accepted: 12/05/2019] [Indexed: 11/05/2022] Open
Abstract
Tidal wetlands are effective carbon sinks, mitigating climate change through the long-term removal of atmospheric CO2. Studies along surface-elevation and thus flooding-frequency gradients in tidal wetlands are often used to understand the effects of accelerated sea-level rise on carbon sequestration, a process that is primarily determined by the balance of primary production and microbial decomposition. It has often been hypothesized that rates of microbial decomposition would increase with elevation and associated increases in soil oxygen availability; however, previous studies yield a wide range of outcomes and equivocal results. Our mechanistic understanding of the elevation-decomposition relationship is limited because most effort has been devoted to understanding the terminal steps of the decomposition process. A few studies assessed microbial exo-enzyme activities (EEAs) as initial and rate-limiting steps that often reveal important insight into microbial energy and nutrient constraints. The present study assessed EEAs and microbial abundance along a coastal ecotone stretching a flooding gradient from tidal flat to high marsh in the European Wadden Sea. We found that stabilization of exo-enzymes to mineral sediments leads to high specific EEAs at low substrate concentrations in frequently flooded, sediment-rich zones of the studied ecotone. We argue that the high background activity of a mineral-associated enzyme pool provides a stable decomposition matrix in highly dynamic, frequently flooded zones. Furthermore, we demonstrate that microbial communities are less nutrient limited in frequently flooded zones, where inputs of nutrient-rich marine organic matter are higher. This was reflected in both increasing exo-enzymatic carbon versus nutrient acquisition and decreasing fungal versus bacterial abundance with increasing flooding frequency. Our findings thereby suggest two previously unrecognized mechanisms that may contribute to stimulated microbial activity despite decreasing oxygen availability in response to accelerated sea-level rise.
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Affiliation(s)
- Peter Mueller
- Institute of Soil ScienceUniversität HamburgHamburgGermany
- Applied Plant EcologyInstitute of Plant Science and MicrobiologyUniversität HamburgHamburgGermany
| | - Dirk Granse
- Applied Plant EcologyInstitute of Plant Science and MicrobiologyUniversität HamburgHamburgGermany
| | - Stefanie Nolte
- School of Environmental SciencesUniversity of East AngliaNorwichUnited Kingdom
- Centre for Environment, Fisheries and Aquaculture ScienceLowestoftUnited Kingdom
| | - Magdalena Weingartner
- Molecular Plant Physiology, Institute of Plant Science and MicrobiologyUniversität HamburgHamburgGermany
| | - Stefan Hoth
- Molecular Plant Physiology, Institute of Plant Science and MicrobiologyUniversität HamburgHamburgGermany
| | - Kai Jensen
- Applied Plant EcologyInstitute of Plant Science and MicrobiologyUniversität HamburgHamburgGermany
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21
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Chen S, Wu J. The sensitivity of soil microbial respiration declined due to crop straw addition but did not depend on the type of crop straw. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:30167-30176. [PMID: 31420839 DOI: 10.1007/s11356-019-06185-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 08/09/2019] [Indexed: 06/10/2023]
Abstract
An incubation experiment was conducted to investigate whether the type of crop straw added to soil influenced the temperature sensitivity of soil microbial respiration. The soil for incubation was collected from a winter wheat-soybean rotation cropland. Five temperature levels (5, 10, 15, 20, and 25 °C), five crop straw types (soybean, peanut, rice, winter wheat, and maize), and a control (CK, no crop straw addition) were established. Soil microbial respiration rates were measured on days 1, 2, 3, 5, 7, 10, 14, 20, and 27 after crop straw addition using an infrared CO2 analyser. Soil enzyme activities of invertase, urea, and catalase and the dissolved organic carbon (DOC) content were measured after incubation. Estimated Q10 (temperature sensitivity of soil microbial respiration) ranged from 1.472 ± 0.045 to 1.970 ± 0.020 and showed no significant (P > 0.05) difference between straw addition treatments, but there was significantly (P < 0.001) higher temperature sensitivity (1.970 ± 0.020) for CK. A significant (P = 0.002) relationship was found between the Q10 of cumulative soil microbial respiration and basal soil microbial respiration (soil microbial respiration at 0 °C). Moreover, a marginally significant (P < 0.1) relationship was found between the Q10 at different incubation stages and basal soil microbial respiration. A quadratic function was used to explain the relationship between estimated basal microbial respiration and the lignin content. Soil microbial respiration was positively correlated with the activities of invertase, urease, and catalase and the dissolved organic carbon (DOC) content in all treatments. This study indicated that crop straw addition significantly (P < 0.001) reduced the Q10 of soil microbial respiration and that the types of crop straw added to soil did not significantly (P > 0.05) change the Q10 value.
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Affiliation(s)
- Shutao Chen
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
- School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
| | - Jing Wu
- School of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, 210044, China
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22
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Min K, Buckeridge K, Ziegler SE, Edwards KA, Bagchi S, Billings SA. Temperature sensitivity of biomass-specific microbial exo-enzyme activities and CO 2 efflux is resistant to change across short- and long-term timescales. GLOBAL CHANGE BIOLOGY 2019; 25:1793-1807. [PMID: 30809844 DOI: 10.1111/gcb.14605] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 02/08/2019] [Indexed: 06/09/2023]
Abstract
Accurate representation of temperature sensitivity (Q10 ) of soil microbial activity across time is critical for projecting soil CO2 efflux. As microorganisms mediate soil carbon (C) loss via exo-enzyme activity and respiration, we explore temperature sensitivities of microbial exo-enzyme activity and respiratory CO2 loss across time and assess mechanisms associated with these potential changes in microbial temperature responses. We collected soils along a latitudinal boreal forest transect with different temperature regimes (long-term timescale) and exposed these soils to laboratory temperature manipulations at 5, 15, and 25°C for 84 days (short-term timescale). We quantified temperature sensitivity of microbial activity per g soil and per g microbial biomass at days 9, 34, 55, and 84, and determined bacterial and fungal community structure before the incubation and at days 9 and 84. All biomass-specific rates exhibited temperature sensitivities resistant to change across short- and long-term timescales (mean Q10 = 2.77 ± 0.25, 2.63 ± 0.26, 1.78 ± 0.26, 2.27 ± 0.25, 3.28 ± 0.44, 2.89 ± 0.55 for β-glucosidase, N-acetyl-β-d-glucosaminidase, leucine amino peptidase, acid phosphatase, cellobiohydrolase, and CO2 efflux, respectively). In contrast, temperature sensitivity of soil mass-specific rates exhibited either resilience (the Q10 value changed and returned to the original value over time) or resistance to change. Regardless of the microbial flux responses, bacterial and fungal community structure was susceptible to change with temperature, significantly differing with short- and long-term exposure to different temperature regimes. Our results highlight that temperature responses of microbial resource allocation to exo-enzyme production and associated respiratory CO2 loss per unit biomass can remain invariant across time, and thus, that vulnerability of soil organic C stocks to rising temperatures may persist in the long term. Furthermore, resistant temperature sensitivities of biomass-specific rates in spite of different community structures imply decoupling of community constituents and the temperature responses of soil microbial activities.
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Affiliation(s)
- Kyungjin Min
- Department of Ecology and Evolutionary Biology, Kansas Biological Survey, University of Kansas, Lawrence, Kansas
| | - Kate Buckeridge
- Department of Ecology and Evolutionary Biology, Kansas Biological Survey, University of Kansas, Lawrence, Kansas
| | - Susan E Ziegler
- Department of Earth Sciences, Memorial University, St. John's, NL, Canada
| | - Kate A Edwards
- Natural Resources Canada, Canadian Forest Service, Ottawa, ON, Canada
| | - Samik Bagchi
- Department of Ecology and Evolutionary Biology, Kansas Biological Survey, University of Kansas, Lawrence, Kansas
| | - Sharon A Billings
- Department of Ecology and Evolutionary Biology, Kansas Biological Survey, University of Kansas, Lawrence, Kansas
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23
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Is There Anybody Out There? Substrate Availability Controls Microbial Activity outside of Hotspots in Subsoils. SOIL SYSTEMS 2018. [DOI: 10.3390/soilsystems2020035] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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24
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Feng W, Liang J, Hale LE, Jung CG, Chen J, Zhou J, Xu M, Yuan M, Wu L, Bracho R, Pegoraro E, Schuur EAG, Luo Y. Enhanced decomposition of stable soil organic carbon and microbial catabolic potentials by long-term field warming. GLOBAL CHANGE BIOLOGY 2017; 23:4765-4776. [PMID: 28597589 DOI: 10.1111/gcb.13755] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 04/24/2017] [Indexed: 06/07/2023]
Abstract
Quantifying soil organic carbon (SOC) decomposition under warming is critical to predict carbon-climate feedbacks. According to the substrate regulating principle, SOC decomposition would decrease as labile SOC declines under field warming, but observations of SOC decomposition under warming do not always support this prediction. This discrepancy could result from varying changes in SOC components and soil microbial communities under warming. This study aimed to determine the decomposition of SOC components with different turnover times after subjected to long-term field warming and/or root exclusion to limit C input, and to test whether SOC decomposition is driven by substrate lability under warming. Taking advantage of a 12-year field warming experiment in a prairie, we assessed the decomposition of SOC components by incubating soils from control and warmed plots, with and without root exclusion for 3 years. We assayed SOC decomposition from these incubations by combining inverse modeling and microbial functional genes during decomposition with a metagenomic technique (GeoChip). The decomposition of SOC components with turnover times of years and decades, which contributed to 95% of total cumulative CO2 respiration, was greater in soils from warmed plots. But the decomposition of labile SOC was similar in warmed plots compared to the control. The diversity of C-degradation microbial genes generally declined with time during the incubation in all treatments, suggesting shifts of microbial functional groups as substrate composition was changing. Compared to the control, soils from warmed plots showed significant increase in the signal intensities of microbial genes involved in degrading complex organic compounds, implying enhanced potential abilities of microbial catabolism. These are likely responsible for accelerated decomposition of SOC components with slow turnover rates. Overall, the shifted microbial community induced by long-term warming accelerates the decomposition of SOC components with slow turnover rates and thus amplify the positive feedback to climate change.
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Affiliation(s)
- Wenting Feng
- National Engineering Laboratory for Improving Quality of Arable Land, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Junyi Liang
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- Environmental Science Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Lauren E Hale
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
| | - Chang Gyo Jung
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Ji Chen
- Center for Ecological and Environmental Sciences, Northwestern Polytechnical University, Xi'an, China
| | - Jizhong Zhou
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
| | - Minggang Xu
- National Engineering Laboratory for Improving Quality of Arable Land, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Mengting Yuan
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
| | - Liyou Wu
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA
| | - Rosvel Bracho
- School of Forest Resources and Conservation, University of Florida, Gainesville, FL, USA
| | - Elaine Pegoraro
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, USA
| | - Edward A G Schuur
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, USA
| | - Yiqi Luo
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
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25
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Studer MS, Künzli R, Maier R, Schmidt MWI, Siegwolf RTW, Woodhatch I, Abiven S. The MICE facility - a new tool to study plant-soil C cycling with a holistic approach. ISOTOPES IN ENVIRONMENTAL AND HEALTH STUDIES 2017; 53:286-297. [PMID: 27846728 DOI: 10.1080/10256016.2016.1254209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 08/18/2016] [Indexed: 06/06/2023]
Abstract
Plant-soil interactions are recognized to play a crucial role in the ecosystem response to climate change. We developed a facility to disentangle the complex interactions behind the plant-soil C feedback mechanisms. The MICE ('Multi-Isotope labelling in a Controlled Environment') facility consists of two climate chambers with independent control of the atmospheric conditions (light, CO2, temperature, humidity) and the soil environment (temperature, moisture). Each chamber holds 15 plant-soil systems with hermetical separation of the shared above ground (shoots) from the individual belowground compartments (roots, rhizosphere, soil). Stable isotopes (e.g. 13C, 15N, 2H, 18O) can be added to either compartment and traced within the whole system. The soil CO2 efflux rate is monitored, and plant material, leached soil water and gas samples are taken frequently. The facility is a powerful tool to improve our mechanistic understanding of plant-soil interactions that drive the C cycle feedback to climate change.
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Affiliation(s)
- Mirjam S Studer
- a Department of Geography , University of Zurich , Zurich , Switzerland
| | | | - Reto Maier
- c Physics Institute, University of Zurich , Zurich , Switzerland
| | | | - Rolf T W Siegwolf
- d Laboratory for Atmospheric Chemistry, Paul Scherrer Institute , Villigen , Switzerland
| | - Ivan Woodhatch
- a Department of Geography , University of Zurich , Zurich , Switzerland
| | - Samuel Abiven
- a Department of Geography , University of Zurich , Zurich , Switzerland
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26
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Min K, Lehmeier CA, Iv FB, Billings SA. Carbon Availability Modifies Temperature Responses of Heterotrophic Microbial Respiration, Carbon Uptake Affinity, and Stable Carbon Isotope Discrimination. Front Microbiol 2016; 7:2083. [PMID: 28082957 PMCID: PMC5184216 DOI: 10.3389/fmicb.2016.02083] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 12/08/2016] [Indexed: 11/15/2022] Open
Abstract
Microbial transformations of organic carbon (OC) generate a large flux of CO2 into the atmosphere and influence the C balance of terrestrial and aquatic ecosystems. Yet, inherent heterogeneity in natural environments precludes direct quantification of multiple microbial C fluxes that underlie CO2 production. Here we used a continuous flow bioreactor coupled with a stable C isotope analyzer to determine the effects of temperature and C availability (cellobiose concentration) on C fluxes and 13C discrimination of a microbial population growing at steady-state in a homogeneous, well-mixed environment. We estimated C uptake affinity and C use efficiency (CUE) to characterize the physiological responses of microbes to changing environmental conditions. Temperature increased biomass-C specific respiration rate and C uptake affinity at lower C availability, but did not influence those parameters at higher C availability. CUE decreased non-linearly with increasing temperature. The non-linear, negative relationship between CUE and temperature was more pronounced under lower C availability than under relatively high C availability. We observed stable isotope fractionation between C substrate and microbial biomass C (7~12‰ depletion), and between microbial biomass and respired CO2 (4~10‰ depletion). Microbial discrimination against 13C-containing cellobiose during C uptake was influenced by temperature and C availability, while discrimination during respiration was only influenced by C availability. Shifts in C uptake affinity with temperature and C availability may have modified uptake-induced 13C fractionation. By stressing the importance of C availability on temperature responses of microbial C fluxes, C uptake affinity, CUE, and isotopic fractionation, this study contributes to a fundamental understanding of C flow through microbes. This will help guide parameterization of microbial responses to varying temperature and C availability within Earth-system models.
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Affiliation(s)
- Kyungjin Min
- Department of Ecology and Evolutionary Biology, Kansas Biological Survey, University of Kansas, Lawrence KS, USA
| | - Christoph A Lehmeier
- Department of Ecology and Evolutionary Biology, Kansas Biological Survey, University of Kansas, Lawrence KS, USA
| | - Ford Ballantyne Iv
- Department of Ecology and Evolutionary Biology, Kansas Biological Survey, University of Kansas, Lawrence KS, USA
| | - Sharon A Billings
- Department of Ecology and Evolutionary Biology, Kansas Biological Survey, University of Kansas, Lawrence KS, USA
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27
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Zhang Q, Wu J, Yang F, Lei Y, Zhang Q, Cheng X. Alterations in soil microbial community composition and biomass following agricultural land use change. Sci Rep 2016; 6:36587. [PMID: 27812029 PMCID: PMC5095713 DOI: 10.1038/srep36587] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 10/17/2016] [Indexed: 01/22/2023] Open
Abstract
The effect of agricultural land use change on soil microbial community composition and biomass remains a widely debated topic. Here, we investigated soil microbial community composition and biomass [e.g., bacteria (B), fungi (F), Arbuscular mycorrhizal fungi (AMF) and Actinomycete (ACT)] using phospholipid fatty acids (PLFAs) analysis, and basal microbial respiration in afforested, cropland and adjacent uncultivated soils in central China. We also investigated soil organic carbon and nitrogen (SOC and SON), labile carbon and nitrogen (LC and LN), recalcitrant carbon and nitrogen (RC and RN), pH, moisture, and temperature. Afforestation averaged higher microbial PLFA biomass compared with cropland and uncultivated soils with higher values in top soils than deep soils. The microbial PLFA biomass was strongly correlated with SON and LC. Higher SOC, SON, LC, LN, moisture and lower pH in afforested soils could be explained approximately 87.3% of total variation of higher total PLFAs. Afforestation also enhanced the F: B ratios compared with cropland. The basal microbial respiration was higher while the basal microbial respiration on a per-unit-PLFA basis was lower in afforested land than adjacent cropland and uncultivated land, suggesting afforestation may increase soil C utilization efficiency and decrease respiration loss in afforested soils.
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Affiliation(s)
- Qian Zhang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, P. R. China
- Graduate University of Chinese Academy of Sciences, Beijing, 10039, China
| | - Junjun Wu
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, P. R. China
- Graduate University of Chinese Academy of Sciences, Beijing, 10039, China
| | - Fan Yang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, P. R. China
- Graduate University of Chinese Academy of Sciences, Beijing, 10039, China
| | - Yao Lei
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, P. R. China
| | - Quanfa Zhang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, P. R. China
| | - Xiaoli Cheng
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, P. R. China
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28
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Auffret MD, Karhu K, Khachane A, Dungait JAJ, Fraser F, Hopkins DW, Wookey PA, Singh BK, Freitag TE, Hartley IP, Prosser JI. The Role of Microbial Community Composition in Controlling Soil Respiration Responses to Temperature. PLoS One 2016; 11:e0165448. [PMID: 27798702 PMCID: PMC5087920 DOI: 10.1371/journal.pone.0165448] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 10/12/2016] [Indexed: 11/19/2022] Open
Abstract
Rising global temperatures may increase the rates of soil organic matter decomposition by heterotrophic microorganisms, potentially accelerating climate change further by releasing additional carbon dioxide (CO2) to the atmosphere. However, the possibility that microbial community responses to prolonged warming may modify the temperature sensitivity of soil respiration creates large uncertainty in the strength of this positive feedback. Both compensatory responses (decreasing temperature sensitivity of soil respiration in the long-term) and enhancing responses (increasing temperature sensitivity) have been reported, but the mechanisms underlying these responses are poorly understood. In this study, microbial biomass, community structure and the activities of dehydrogenase and β-glucosidase enzymes were determined for 18 soils that had previously demonstrated either no response or varying magnitude of enhancing or compensatory responses of temperature sensitivity of heterotrophic microbial respiration to prolonged cooling. The soil cooling approach, in contrast to warming experiments, discriminates between microbial community responses and the consequences of substrate depletion, by minimising changes in substrate availability. The initial microbial community composition, determined by molecular analysis of soils showing contrasting respiration responses to cooling, provided evidence that the magnitude of enhancing responses was partly related to microbial community composition. There was also evidence that higher relative abundance of saprophytic Basidiomycota may explain the compensatory response observed in one soil, but neither microbial biomass nor enzymatic capacity were significantly affected by cooling. Our findings emphasise the key importance of soil microbial community responses for feedbacks to global change, but also highlight important areas where our understanding remains limited.
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Affiliation(s)
- Marc D. Auffret
- University of Aberdeen, Cruickshank Building St Machar Drive, Aberdeen AB24 3UU, United Kingdom
- * E-mail:
| | - Kristiina Karhu
- University of Exeter Amory Building, Rennes Drive, Exeter EX4 4RJ, United Kingdom
| | - Amit Khachane
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith 2751 NSW, Australia
| | - Jennifer A. J. Dungait
- Sustainable Soils and Grassland Systems Department, Rothamsted Research North Wyke, Okehampton, EX20 2SB, United Kingdom
| | - Fiona Fraser
- School of Energy, Environment and Agrifood, Cranfield University, Cranfield, Bedfordshire, MK43 0AL, United Kingdom
| | - David W. Hopkins
- The Royal Agricultural University, Cirencester, Gloucestershire, GL7 6JS, United Kingdom
| | - Philip A. Wookey
- Institute of Life & Earth Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, United Kingdom
| | - Brajesh K. Singh
- Hawkesbury Institute for the Environment, University of Western Sydney, Penrith 2751 NSW, Australia
| | - Thomas E. Freitag
- The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, United Kingdom
| | - Iain P. Hartley
- University of Exeter Amory Building, Rennes Drive, Exeter EX4 4RJ, United Kingdom
| | - James I. Prosser
- University of Aberdeen, Cruickshank Building St Machar Drive, Aberdeen AB24 3UU, United Kingdom
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29
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Malik AA, Chowdhury S, Schlager V, Oliver A, Puissant J, Vazquez PGM, Jehmlich N, von Bergen M, Griffiths RI, Gleixner G. Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling. Front Microbiol 2016; 7:1247. [PMID: 27555839 PMCID: PMC4977315 DOI: 10.3389/fmicb.2016.01247] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 07/27/2016] [Indexed: 11/13/2022] Open
Abstract
Despite several lines of observational evidence, there is a lack of consensus on whether higher fungal:bacterial (F:B) ratios directly cause higher soil carbon (C) storage. We employed RNA sequencing, protein profiling and isotope tracer techniques to evaluate whether differing F:B ratios are associated with differences in C storage. A mesocosm (13)C labeled foliar litter decomposition experiment was performed in two soils that were similar in their physico-chemical properties but differed in microbial community structure, specifically their F:B ratio (determined by PLFA analyses, RNA sequencing and protein profiling; all three corroborating each other). Following litter addition, we observed a consistent increase in abundance of fungal phyla; and greater increases in the fungal dominated soil; implicating the role of fungi in litter decomposition. Litter derived (13)C in respired CO2 was consistently lower, and residual (13)C in bulk SOM was higher in high F:B soil demonstrating greater C storage potential in the F:B dominated soil. We conclude that in this soil system, the increased abundance of fungi in both soils and the altered C cycling patterns in the F:B dominated soils highlight the significant role of fungi in litter decomposition and indicate that F:B ratios are linked to higher C storage potential.
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Affiliation(s)
- Ashish A. Malik
- Department of Biogeochemical Processes, Max Planck Institute for BiogeochemistryJena, Germany
- Centre for Ecology and HydrologyWallingford, UK
| | - Somak Chowdhury
- Department of Biogeochemical Processes, Max Planck Institute for BiogeochemistryJena, Germany
| | - Veronika Schlager
- Department of Biogeochemical Processes, Max Planck Institute for BiogeochemistryJena, Germany
| | - Anna Oliver
- Centre for Ecology and HydrologyWallingford, UK
| | | | - Perla G. M. Vazquez
- Department of Biogeochemical Processes, Max Planck Institute for BiogeochemistryJena, Germany
| | - Nico Jehmlich
- Department of Proteomics, Helmholtz Centre for Environmental ResearchLeipzig, Germany
| | - Martin von Bergen
- Department of Proteomics, Helmholtz Centre for Environmental ResearchLeipzig, Germany
- Department of Metabolomics, Helmholtz Centre for Environmental ResearchLeipzig, Germany
- Institute of Biochemistry, Faculty of Biosciences, Pharmacy and Psychology, University of LeipzigLeipzig, Germany
- Department of Life Sciences and Chemistry, Aalborg UniversityAalborg, Denmark
| | | | - Gerd Gleixner
- Department of Biogeochemical Processes, Max Planck Institute for BiogeochemistryJena, Germany
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30
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Temperature Dependence of Soil Respiration Modulated by Thresholds in Soil Water Availability Across European Shrubland Ecosystems. Ecosystems 2016. [DOI: 10.1007/s10021-016-0016-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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31
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Sinsabaugh RL, Turner BL, Talbot JM, Waring BG, Powers JS, Kuske CR, Moorhead DL, Follstad Shah JJ. Stoichiometry of microbial carbon use efficiency in soils. ECOL MONOGR 2016. [DOI: 10.1890/15-2110.1] [Citation(s) in RCA: 165] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
| | - Benjamin L. Turner
- Smithsonian Tropical Research Institute Apartado 0843‐03092 Balboa, Ancon Panama
| | - Jennifer M. Talbot
- Department of Biology Boston University 5 Cummington Mall Boston Massachusetts 02215 USA
| | - Bonnie G. Waring
- Department of Ecology, Evolution, and Behavior University of Minnesota St. Paul Minnesota 55108 USA
| | - Jennifer S. Powers
- Department of Ecology, Evolution, and Behavior University of Minnesota St. Paul Minnesota 55108 USA
- Department of Plant Biology University of Minnesota St. Paul Minnesota 55108 USA
| | - Cheryl R. Kuske
- Bioscience Division Los Alamos National Laboratory Los Alamos New Mexico 87545 USA
| | - Daryl L. Moorhead
- Department of Environmental Sciences University of Toledo 2810 West Bancroft Street Toledo Ohio 43606 USA
| | - Jennifer J. Follstad Shah
- Environmental and Sustainable Studies Program University of Utah 260 South Central Campus Drive Salt Lake City Utah 84112 USA
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32
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Bond-Lamberty B, Bolton H, Fansler S, Heredia-Langner A, Liu C, McCue LA, Smith J, Bailey V. Soil Respiration and Bacterial Structure and Function after 17 Years of a Reciprocal Soil Transplant Experiment. PLoS One 2016; 11:e0150599. [PMID: 26934712 PMCID: PMC4775055 DOI: 10.1371/journal.pone.0150599] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Accepted: 02/17/2016] [Indexed: 11/18/2022] Open
Abstract
The effects of climate change on soil organic matter-its structure, microbial community, carbon storage, and respiration response-remain uncertain and widely debated. In addition, the effects of climate changes on ecosystem structure and function are often modulated or delayed, meaning that short-term experiments are not sufficient to characterize ecosystem responses. This study capitalized on a long-term reciprocal soil transplant experiment to examine the response of dryland soils to climate change. The two transplant sites were separated by 500 m of elevation on the same mountain slope in eastern Washington state, USA, and had similar plant species and soil types. We resampled the original 1994 soil transplants and controls, measuring CO2 production, temperature response, enzyme activity, and bacterial community structure after 17 years. Over a laboratory incubation of 100 days, reciprocally transplanted soils respired roughly equal cumulative amounts of carbon as non-transplanted controls from the same site. Soils transplanted from the hot, dry, lower site to the cooler and wetter (difference of -5°C monthly maximum air temperature, +50 mm yr-1 precipitation) upper site exhibited almost no respiratory response to temperature (Q10 of 1.1), but soils originally from the upper, cooler site had generally higher respiration rates. The bacterial community structure of transplants did not differ significantly from that of untransplanted controls, however. Slight differences in local climate between the upper and lower Rattlesnake locations, simulated with environmental control chambers during the incubation, thus prompted significant differences in microbial activity, with no observed change to bacterial structure. These results support the idea that environmental shifts can influence soil C through metabolic changes, and suggest that microbial populations responsible for soil heterotrophic respiration may be constrained in surprising ways, even as shorter- and longer-term soil microbial dynamics may be significantly different under changing climate.
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Affiliation(s)
- Ben Bond-Lamberty
- Pacific Northwest National Laboratory, Joint Global Change Research Institute at the University of Maryland–College Park, 5825 University Research Court #3500, College Park, MD, 20740, United States of America
- * E-mail:
| | - Harvey Bolton
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA, 99352, United States of America
| | - Sarah Fansler
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA, 99352, United States of America
| | - Alejandro Heredia-Langner
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA, 99352, United States of America
| | - Chongxuan Liu
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA, 99352, United States of America
| | - Lee Ann McCue
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA, 99352, United States of America
| | - Jeffrey Smith
- USDA-ARS, 215 Johnson Hall, Washington State University, Pullman, WA, 99164, United States of America
| | - Vanessa Bailey
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA, 99352, United States of America
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33
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He N, Yu G. Stoichiometrical regulation of soil organic matter decomposition and its temperature sensitivity. Ecol Evol 2016; 6:620-7. [PMID: 26843944 PMCID: PMC4729244 DOI: 10.1002/ece3.1927] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Revised: 12/08/2015] [Accepted: 12/09/2015] [Indexed: 11/11/2022] Open
Abstract
The decomposition of soil organic matter (SOM) can be described by a set of kinetic principles, environmental constraints, and substrate supply. Here, we hypothesized that SOM decomposition rates (R) and its temperature sensitivity (Q 10) would increase steadily with the N:C ratios of added substrates by alleviating N limitation on microbial growth. We tested this hypothesis by investigating SOM decomposition in both grassland and forest soils after addition of substrates with a range of N:C ratios. The results showed that Michaelis-Menten equations well fit the response of R to the N:C ratio variations of added substrates, and their coefficients of determination (R (2)) ranged from 0.65 to 0.89 (P < 0.01). Moreover, the maximal R, Q 10, and cumulative C emission of SOM decomposition increased exponentially with the N:C ratios of added substrates, and were controlled interactively by incubation temperature and the N:C ratios of the added substrates. We demonstrated that SOM decomposition rate and temperature sensitivity were exponentially correlated to substrate stoichiometry (N:C ratio) in both grassland and forest soils. Therefore, these correlations should be incorporated into the models for the prediction of SOM decomposition rate under warmer climatic scenarios.
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Affiliation(s)
- Nianpeng He
- Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China
| | - Guirui Yu
- Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China
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34
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Nottingham AT, Whitaker J, Turner BL, Salinas N, Zimmermann M, Malhi Y, Meir P. Climate Warming and Soil Carbon in Tropical Forests: Insights from an Elevation Gradient in the Peruvian Andes. Bioscience 2015; 65:906-921. [PMID: 26955086 PMCID: PMC4777015 DOI: 10.1093/biosci/biv109] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The temperature sensitivity of soil organic matter (SOM) decomposition in tropical forests will influence future climate. Studies of a 3.5-kilometer elevation gradient in the Peruvian Andes, including short-term translocation experiments and the examination of the long-term adaptation of biota to local thermal and edaphic conditions, have revealed several factors that may regulate this sensitivity. Collectively this work suggests that, in the absence of a moisture constraint, the temperature sensitivity of decomposition is regulated by the chemical composition of plant debris (litter) and both the physical and chemical composition of preexisting SOM: higher temperature sensitivities are found in litter or SOM that is more chemically complex and in SOM that is less occluded within aggregates. In addition, the temperature sensitivity of SOM in tropical montane forests may be larger than previously recognized because of the presence of "cold-adapted" and nitrogen-limited microbial decomposers and the possible future alterations in plant and microbial communities associated with warming. Studies along elevation transects, such as those reviewed here, can reveal factors that will regulate the temperature sensitivity of SOM. They can also complement and guide in situ soil-warming experiments, which will be needed to understand how this vulnerability to temperature may be mediated by altered plant productivity under future climatic change.
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Affiliation(s)
- Andrew T Nottingham
- Andrew T. Nottingham ( ) is affiliated with the School of Geosciences at the University of Edinburgh, in the United Kingdom. Jeanette Whitaker is with the Centre for Ecology and Hydrology at the Lancaster Environment Centre, in Lancaster, United Kingdom. Benjamin L. Turner is affiliated with the Smithsonian Tropical Research Institute, in Balboa, Ancon, Republic of Panama. Norma Salinas is with the Seccion Química at the Universidad La Católica, in Lima, Peru. Michael Zimmermann is affiliated with the University of Natural Resources and Applied Life Sciences, in Vienna, Austria. Yadvinder Malhi is with the Environmental Change Institute in the School of Geography and the Environment at the University of Oxford, in the United Kingdom. Patrick Meir is affiliated with the Research School of Biology at Australian National University, in Canberra, and with the School of Geosciences at the University of Edinburgh, in the United Kingdom
| | - Jeanette Whitaker
- Andrew T. Nottingham ( ) is affiliated with the School of Geosciences at the University of Edinburgh, in the United Kingdom. Jeanette Whitaker is with the Centre for Ecology and Hydrology at the Lancaster Environment Centre, in Lancaster, United Kingdom. Benjamin L. Turner is affiliated with the Smithsonian Tropical Research Institute, in Balboa, Ancon, Republic of Panama. Norma Salinas is with the Seccion Química at the Universidad La Católica, in Lima, Peru. Michael Zimmermann is affiliated with the University of Natural Resources and Applied Life Sciences, in Vienna, Austria. Yadvinder Malhi is with the Environmental Change Institute in the School of Geography and the Environment at the University of Oxford, in the United Kingdom. Patrick Meir is affiliated with the Research School of Biology at Australian National University, in Canberra, and with the School of Geosciences at the University of Edinburgh, in the United Kingdom
| | - Benjamin L Turner
- Andrew T. Nottingham ( ) is affiliated with the School of Geosciences at the University of Edinburgh, in the United Kingdom. Jeanette Whitaker is with the Centre for Ecology and Hydrology at the Lancaster Environment Centre, in Lancaster, United Kingdom. Benjamin L. Turner is affiliated with the Smithsonian Tropical Research Institute, in Balboa, Ancon, Republic of Panama. Norma Salinas is with the Seccion Química at the Universidad La Católica, in Lima, Peru. Michael Zimmermann is affiliated with the University of Natural Resources and Applied Life Sciences, in Vienna, Austria. Yadvinder Malhi is with the Environmental Change Institute in the School of Geography and the Environment at the University of Oxford, in the United Kingdom. Patrick Meir is affiliated with the Research School of Biology at Australian National University, in Canberra, and with the School of Geosciences at the University of Edinburgh, in the United Kingdom
| | - Norma Salinas
- Andrew T. Nottingham ( ) is affiliated with the School of Geosciences at the University of Edinburgh, in the United Kingdom. Jeanette Whitaker is with the Centre for Ecology and Hydrology at the Lancaster Environment Centre, in Lancaster, United Kingdom. Benjamin L. Turner is affiliated with the Smithsonian Tropical Research Institute, in Balboa, Ancon, Republic of Panama. Norma Salinas is with the Seccion Química at the Universidad La Católica, in Lima, Peru. Michael Zimmermann is affiliated with the University of Natural Resources and Applied Life Sciences, in Vienna, Austria. Yadvinder Malhi is with the Environmental Change Institute in the School of Geography and the Environment at the University of Oxford, in the United Kingdom. Patrick Meir is affiliated with the Research School of Biology at Australian National University, in Canberra, and with the School of Geosciences at the University of Edinburgh, in the United Kingdom
| | - Michael Zimmermann
- Andrew T. Nottingham ( ) is affiliated with the School of Geosciences at the University of Edinburgh, in the United Kingdom. Jeanette Whitaker is with the Centre for Ecology and Hydrology at the Lancaster Environment Centre, in Lancaster, United Kingdom. Benjamin L. Turner is affiliated with the Smithsonian Tropical Research Institute, in Balboa, Ancon, Republic of Panama. Norma Salinas is with the Seccion Química at the Universidad La Católica, in Lima, Peru. Michael Zimmermann is affiliated with the University of Natural Resources and Applied Life Sciences, in Vienna, Austria. Yadvinder Malhi is with the Environmental Change Institute in the School of Geography and the Environment at the University of Oxford, in the United Kingdom. Patrick Meir is affiliated with the Research School of Biology at Australian National University, in Canberra, and with the School of Geosciences at the University of Edinburgh, in the United Kingdom
| | - Yadvinder Malhi
- Andrew T. Nottingham ( ) is affiliated with the School of Geosciences at the University of Edinburgh, in the United Kingdom. Jeanette Whitaker is with the Centre for Ecology and Hydrology at the Lancaster Environment Centre, in Lancaster, United Kingdom. Benjamin L. Turner is affiliated with the Smithsonian Tropical Research Institute, in Balboa, Ancon, Republic of Panama. Norma Salinas is with the Seccion Química at the Universidad La Católica, in Lima, Peru. Michael Zimmermann is affiliated with the University of Natural Resources and Applied Life Sciences, in Vienna, Austria. Yadvinder Malhi is with the Environmental Change Institute in the School of Geography and the Environment at the University of Oxford, in the United Kingdom. Patrick Meir is affiliated with the Research School of Biology at Australian National University, in Canberra, and with the School of Geosciences at the University of Edinburgh, in the United Kingdom
| | - Patrick Meir
- Andrew T. Nottingham ( ) is affiliated with the School of Geosciences at the University of Edinburgh, in the United Kingdom. Jeanette Whitaker is with the Centre for Ecology and Hydrology at the Lancaster Environment Centre, in Lancaster, United Kingdom. Benjamin L. Turner is affiliated with the Smithsonian Tropical Research Institute, in Balboa, Ancon, Republic of Panama. Norma Salinas is with the Seccion Química at the Universidad La Católica, in Lima, Peru. Michael Zimmermann is affiliated with the University of Natural Resources and Applied Life Sciences, in Vienna, Austria. Yadvinder Malhi is with the Environmental Change Institute in the School of Geography and the Environment at the University of Oxford, in the United Kingdom. Patrick Meir is affiliated with the Research School of Biology at Australian National University, in Canberra, and with the School of Geosciences at the University of Edinburgh, in the United Kingdom
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Zhou Z, Xu M, Kang F, Jianxin Sun O. Maximum temperature accounts for annual soil CO2 efflux in temperate forests of Northern China. Sci Rep 2015; 5:12142. [PMID: 26179467 PMCID: PMC4503994 DOI: 10.1038/srep12142] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Accepted: 06/16/2015] [Indexed: 11/26/2022] Open
Abstract
It will help understand the representation legality of soil temperature to explore the correlations of soil respiration with variant properties of soil temperature. Soil temperature at 10 cm depth was hourly logged through twelve months. Basing on the measured soil temperature, soil respiration at different temporal scales were calculated using empirical functions for temperate forests. On monthly scale, soil respiration significantly correlated with maximum, minimum, mean and accumulated effective soil temperatures. Annual soil respiration varied from 409 g C m−2 in coniferous forest to 570 g C m−2 in mixed forest and to 692 g C m−2 in broadleaved forest, and was markedly explained by mean soil temperatures of the warmest day, July and summer, separately. These three soil temperatures reflected the maximum values on diurnal, monthly and annual scales. In accordance with their higher temperatures, summer soil respiration accounted for 51% of annual soil respiration across forest types, and broadleaved forest also had higher soil organic carbon content (SOC) and soil microbial biomass carbon content (SMBC), but a lower contribution of SMBC to SOC. This added proof to the findings that maximum soil temperature may accelerate the transformation of SOC to CO2-C via stimulating activities of soil microorganisms.
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Affiliation(s)
- Zhiyong Zhou
- 1] Ministry of Education Key Laboratory for Silviculture and Conservation, Beijing Forestry University, Beijing, 100083, China [2] The Institute of Forestry and Climate Change Research, Beijing Forestry University, Beijing, 100083, China
| | - Meili Xu
- 1] Ministry of Education Key Laboratory for Silviculture and Conservation, Beijing Forestry University, Beijing, 100083, China [2] The Institute of Forestry and Climate Change Research, Beijing Forestry University, Beijing, 100083, China
| | - Fengfeng Kang
- Ministry of Education Key Laboratory for Silviculture and Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Osbert Jianxin Sun
- 1] Ministry of Education Key Laboratory for Silviculture and Conservation, Beijing Forestry University, Beijing, 100083, China [2] The Institute of Forestry and Climate Change Research, Beijing Forestry University, Beijing, 100083, China
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Li J, He N, Wei X, Gao Y, Zuo Y. Changes in Temperature Sensitivity and Activation Energy of Soil Organic Matter Decomposition in Different Qinghai-Tibet Plateau Grasslands. PLoS One 2015; 10:e0132795. [PMID: 26176705 PMCID: PMC4503348 DOI: 10.1371/journal.pone.0132795] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2014] [Accepted: 06/18/2015] [Indexed: 12/03/2022] Open
Abstract
Qinghai-Tibet Plateau grasslands are unique geographical regions and store substantial soil organic matter (SOM) in the soil surface, which make them very sensitive to global climate change. Here, we focused on three main grassland types (alpine meadow, steppe, and desert) and conducted a soil incubation experiment at five different temperatures (5, 10, 15, 20, and 25°C) to investigate SOM decomposition rates (R), temperature sensitivity (Q10), and activation energy (Ea). The results showed that grassland type and incubation temperature had significant impact on R (P < 0.001), and the values of R were exponential correlated with incubation temperature in three alpine grasslands. At the same temperature, R was in the following order: alpine meadow > alpinesteppe > alpine desert. The Q10 values differed significantly among different grasslands, and the overall trends were as follows: alpine meadow (1.56 ± 0.09) < alpine steppe (1.88 ± 0.23) < alpine desert (2.39 ± 0.32). Moreover, the Ea values differed significantly across different grassland types (P < 0.001) and increased with increasing incubation time. The exponential negative correlations between Ea and R at 20°C across all grassland types (all Ps < 0.001) indicated that the substrate-quality temperature hypothesis is applicable to the alpine grasslands. Our findings provide new insights for understanding the responses of SOM decomposition and storage to warming scenarios in this Plateau.
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Affiliation(s)
- Jie Li
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
- Institute of Grassland Science, Northeast Normal University, Changchun, 130024, China
- Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, 130024, China
| | - Nianpeng He
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
- * E-mail: (NH); (XW)
| | - Xuehong Wei
- Agricultural and Animal Husbandry College of Tibet University, Linzhi, 860000, China
- * E-mail: (NH); (XW)
| | - Yang Gao
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yao Zuo
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
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37
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Cross WF, Hood JM, Benstead JP, Huryn AD, Nelson D. Interactions between temperature and nutrients across levels of ecological organization. GLOBAL CHANGE BIOLOGY 2015; 21:1025-40. [PMID: 25400273 DOI: 10.1111/gcb.12809] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Accepted: 10/06/2014] [Indexed: 05/04/2023]
Abstract
Temperature and nutrient availability play key roles in controlling the pathways and rates at which energy and materials move through ecosystems. These factors have also changed dramatically on Earth over the past century as human activities have intensified. Although significant effort has been devoted to understanding the role of temperature and nutrients in isolation, less is known about how these two factors interact to influence ecological processes. Recent advances in ecological stoichiometry and metabolic ecology provide a useful framework for making progress in this area, but conceptual synthesis and review are needed to help catalyze additional research. Here, we examine known and potential interactions between temperature and nutrients from a variety of physiological, community, and ecosystem perspectives. We first review patterns at the level of the individual, focusing on four traits--growth, respiration, body size, and elemental content--that should theoretically govern how temperature and nutrients interact to influence higher levels of biological organization. We next explore the interactive effects of temperature and nutrients on populations, communities, and food webs by synthesizing information related to community size spectra, biomass distributions, and elemental composition. We use metabolic theory to make predictions about how population-level secondary production should respond to interactions between temperature and resource supply, setting up qualitative predictions about the flows of energy and materials through metazoan food webs. Last, we examine how temperature-nutrient interactions influence processes at the whole-ecosystem level, focusing on apparent vs. intrinsic activation energies of ecosystem processes, how to represent temperature-nutrient interactions in ecosystem models, and patterns with respect to nutrient uptake and organic matter decomposition. We conclude that a better understanding of interactions between temperature and nutrients will be critical for developing realistic predictions about ecological responses to multiple, simultaneous drivers of global change, including climate warming and elevated nutrient supply.
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Affiliation(s)
- Wyatt F Cross
- Department of Ecology, Montana State University, Bozeman, MT, 59717, USA
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38
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Wang Q, Wang D, Wen X, Yu G, He N, Wang R. Differences in SOM decomposition and temperature sensitivity among soil aggregate size classes in a temperate grasslands. PLoS One 2015; 10:e0117033. [PMID: 25692291 PMCID: PMC4334239 DOI: 10.1371/journal.pone.0117033] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 12/17/2014] [Indexed: 11/19/2022] Open
Abstract
The principle of enzyme kinetics suggests that the temperature sensitivity (Q10) of soil organic matter (SOM) decomposition is inversely related to organic carbon (C) quality, i.e., the C quality-temperature (CQT) hypothesis. We tested this hypothesis by performing laboratory incubation experiments with bulk soil, macroaggregates (MA, 250-2000 μm), microaggregates (MI, 53-250 μm), and mineral fractions (MF, <53 μm) collected from an Inner Mongolian temperate grassland. The results showed that temperature and aggregate size significantly affected on SOM decomposition, with notable interactive effects (P<0.0001). For 2 weeks, the decomposition rates of bulk soil and soil aggregates increased with increasing incubation temperature in the following order: MA>MF>bulk soil >MI(P <0.05). The Q10 values were highest for MA, followed (in decreasing order) by bulk soil, MF, and MI. Similarly, the activation energies (Ea) for MA, bulk soil, MF, and MI were 48.47, 33.26, 27.01, and 23.18 KJ mol-1, respectively. The observed significant negative correlations between Q10 and C quality index in bulk soil and soil aggregates (P<0.05) suggested that the CQT hypothesis is applicable to soil aggregates. Cumulative C emission differed significantly among aggregate size classes (P <0.0001), with the largest values occurring in MA (1101 μg g-1), followed by MF (976 μg g-1) and MI (879 μg g-1). These findings suggest that feedback from SOM decomposition in response to changing temperature is closely associated withsoil aggregation and highlights the complex responses of ecosystem C budgets to future warming scenarios.
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Affiliation(s)
- Qing Wang
- Resources and Environment College, Anhui Agricultural University, Hefei, China
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Dan Wang
- Resources and Environment College, Anhui Agricultural University, Hefei, China
| | - Xuefa Wen
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Guirui Yu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Nianpeng He
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Rongfu Wang
- Resources and Environment College, Anhui Agricultural University, Hefei, China
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Whitaker J, Ostle N, McNamara NP, Nottingham AT, Stott AW, Bardgett RD, Salinas N, Ccahuana AJQ, Meir P. Microbial carbon mineralization in tropical lowland and montane forest soils of Peru. Front Microbiol 2014; 5:720. [PMID: 25566230 PMCID: PMC4270188 DOI: 10.3389/fmicb.2014.00720] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 12/02/2014] [Indexed: 11/13/2022] Open
Abstract
Climate change is affecting the amount and complexity of plant inputs to tropical forest soils. This is likely to influence the carbon (C) balance of these ecosystems by altering decomposition processes e.g., "positive priming effects" that accelerate soil organic matter mineralization. However, the mechanisms determining the magnitude of priming effects are poorly understood. We investigated potential mechanisms by adding (13)C labeled substrates, as surrogates of plant inputs, to soils from an elevation gradient of tropical lowland and montane forests. We hypothesized that priming effects would increase with elevation due to increasing microbial nitrogen limitation, and that microbial community composition would strongly influence the magnitude of priming effects. Quantifying the sources of respired C (substrate or soil organic matter) in response to substrate addition revealed no consistent patterns in priming effects with elevation. Instead we found that substrate quality (complexity and nitrogen content) was the dominant factor controlling priming effects. For example a nitrogenous substrate induced a large increase in soil organic matter mineralization whilst a complex C substrate caused negligible change. Differences in the functional capacity of specific microbial groups, rather than microbial community composition per se, were responsible for these substrate-driven differences in priming effects. Our findings suggest that the microbial pathways by which plant inputs and soil organic matter are mineralized are determined primarily by the quality of plant inputs and the functional capacity of microbial taxa, rather than the abiotic properties of the soil. Changes in the complexity and stoichiometry of plant inputs to soil in response to climate change may therefore be important in regulating soil C dynamics in tropical forest soils.
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Affiliation(s)
- Jeanette Whitaker
- Centre for Ecology & Hydrology, Lancaster Environment Centre Lancaster, UK
| | - Nicholas Ostle
- Soil and Ecosystem Laboratory, Lancaster Environment Centre, Lancaster University Lancaster, UK
| | - Niall P McNamara
- Centre for Ecology & Hydrology, Lancaster Environment Centre Lancaster, UK
| | | | - Andrew W Stott
- Centre for Ecology & Hydrology, Lancaster Environment Centre Lancaster, UK
| | | | - Norma Salinas
- Seccion Química, Pontificia Universidad Católica del Perú Lima, Peru ; School of Geography and the Environment, Environmental Change Institute, University of Oxford Oxford, UK
| | - Adan J Q Ccahuana
- Facultad de Ciencias Biologicas, Universidad Nacional de San Antonio Abad Cusco, Peru
| | - Patrick Meir
- School of Geosciences, University of Edinburgh Edinburgh, UK
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40
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Jia X, Zhou X, Luo Y, Xue K, Xue X, Xu X, Yang Y, Wu L, Zhou J. Effects of substrate addition on soil respiratory carbon release under long-term warming and clipping in a tallgrass prairie. PLoS One 2014; 9:e114203. [PMID: 25490701 PMCID: PMC4260856 DOI: 10.1371/journal.pone.0114203] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 11/05/2014] [Indexed: 11/18/2022] Open
Abstract
Regulatory mechanisms of soil respiratory carbon (C) release induced by substrates (i.e., plant derived substrates) are critical for predicting ecosystem responses to climate change, but the mechanisms are not well understood. In this study, we sampled soils from a long-term field manipulative experiment and conducted a laboratory incubation to explore the role of substrate supply in regulating the differences in soil C release among the experimental treatments, including control, warming, clipping, and warming plus clipping. Three types of substrates (glucose, C3 and C4 plant materials) were added with an amount equal to 1% of soil dry weight under the four treatments. We found that the addition of all three substrates significantly stimulated soil respiratory C release in all four warming and clipping treatments. In soils without substrate addition, warming significantly stimulated soil C release but clipping decreased it. However, additions of glucose and C3 plant materials (C3 addition) offset the warming effects, whereas C4 addition still showed the warming-induced stimulation of soil C release. Our results suggest that long-term warming may inhibit microbial capacity for decomposition of C3 litter but may enhance it for decomposition of C4 litter. Such warming-induced adaptation of microbial communities may weaken the positive C-cycle feedback to warming due to increased proportion of C4 species in plant community and decreased litter quality. In contrast, clipping may weaken microbial capacity for warming-induced decomposition of C4 litter but may enhance it for C3 litter. Warming- and clipping-induced shifts in microbial metabolic capacity may be strongly associated with changes in plant species composition and could substantially influence soil C dynamics in response to global change.
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Affiliation(s)
- Xiaohong Jia
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China
- Shapotou Desert Research and Experimental Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma 73019, United States of America
| | - Xuhui Zhou
- Coastal Ecosystems Research Station of Yangtze River Estuary, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, The Institute of Biodiversity Science, Fudan University, Shanghai 200433, China
- * E-mail:
| | - Yiqi Luo
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma 73019, United States of America
| | - Kai Xue
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma 73019, United States of America
| | - Xian Xue
- Shapotou Desert Research and Experimental Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma 73019, United States of America
| | - Xia Xu
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma 73019, United States of America
| | - Yuanhe Yang
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma 73019, United States of America
| | - Liyou Wu
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma 73019, United States of America
| | - Jizhong Zhou
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma 73019, United States of America
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41
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Jankowski K, Schindler DE, Lisi PJ. Temperature sensitivity of community respiration rates in streams is associated with watershed geomorphic features. Ecology 2014. [DOI: 10.1890/14-0608.1] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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42
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Temperature sensitivity of soil respiration rates enhanced by microbial community response. Nature 2014; 513:81-4. [PMID: 25186902 DOI: 10.1038/nature13604] [Citation(s) in RCA: 214] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 06/17/2014] [Indexed: 11/09/2022]
Abstract
Soils store about four times as much carbon as plant biomass, and soil microbial respiration releases about 60 petagrams of carbon per year to the atmosphere as carbon dioxide. Short-term experiments have shown that soil microbial respiration increases exponentially with temperature. This information has been incorporated into soil carbon and Earth-system models, which suggest that warming-induced increases in carbon dioxide release from soils represent an important positive feedback loop that could influence twenty-first-century climate change. The magnitude of this feedback remains uncertain, however, not least because the response of soil microbial communities to changing temperatures has the potential to either decrease or increase warming-induced carbon losses substantially. Here we collect soils from different ecosystems along a climate gradient from the Arctic to the Amazon and investigate how microbial community-level responses control the temperature sensitivity of soil respiration. We find that the microbial community-level response more often enhances than reduces the mid- to long-term (90 days) temperature sensitivity of respiration. Furthermore, the strongest enhancing responses were observed in soils with high carbon-to-nitrogen ratios and in soils from cold climatic regions. After 90 days, microbial community responses increased the temperature sensitivity of respiration in high-latitude soils by a factor of 1.4 compared to the instantaneous temperature response. This suggests that the substantial carbon stores in Arctic and boreal soils could be more vulnerable to climate warming than currently predicted.
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Streit K, Hagedorn F, Hiltbrunner D, Portmann M, Saurer M, Buchmann N, Wild B, Richter A, Wipf S, Siegwolf RTW. Soil warming alters microbial substrate use in alpine soils. GLOBAL CHANGE BIOLOGY 2014; 20:1327-1338. [PMID: 24106016 DOI: 10.1111/gcb.12396] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 09/07/2013] [Indexed: 06/02/2023]
Abstract
Will warming lead to an increased use of older soil organic carbon (SOC) by microbial communities, thereby inducing C losses from C-rich alpine soils? We studied soil microbial community composition, activity, and substrate use after 3 and 4 years of soil warming (+4 °C, 2007-2010) at the alpine treeline in Switzerland. The warming experiment was nested in a free air CO2 enrichment experiment using depleted (13)CO2 (δ(13)C = -30‰, 2001-2009). We traced this depleted (13)C label in phospholipid fatty acids (PLFA) of the organic layer (0-5 cm soil depth) and in C mineralized from root-free soils to distinguish substrate ages used by soil microorganisms: fixed before 2001 ('old'), from 2001 to 2009 ('new') or in 2010 ('recent'). Warming induced a sustained stimulation of soil respiration (+38%) without decline in mineralizable SOC. PLFA concentrations did not reveal changes in microbial community composition due to soil warming, but soil microbial metabolic activity was stimulated (+66%). Warming decreased the amount of new and recent C in the fungal biomarker 18:2ω6,9 and the amount of new C mineralized from root-free soils, implying a shift in microbial substrate use toward a greater use of old SOC. This shift in substrate use could indicate an imbalance between C inputs and outputs, which could eventually decrease SOC storage in this alpine ecosystem.
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Affiliation(s)
- Kathrin Streit
- Paul Scherrer Institute (PSI), Laboratory of Atmospheric Chemistry, Villigen PSI, 5232, Switzerland
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44
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Zhou W, Hui D, Shen W. Effects of soil moisture on the temperature sensitivity of soil heterotrophic respiration: a laboratory incubation study. PLoS One 2014; 9:e92531. [PMID: 24647610 PMCID: PMC3960259 DOI: 10.1371/journal.pone.0092531] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 02/23/2014] [Indexed: 11/22/2022] Open
Abstract
The temperature sensitivity (Q10) of soil heterotrophic respiration (Rh) is an important ecological model parameter and may vary with temperature and moisture. While Q10 generally decreases with increasing temperature, the moisture effects on Q10 have been controversial. To address this, we conducted a 90-day laboratory incubation experiment using a subtropical forest soil with a full factorial combination of five moisture levels (20%, 40%, 60%, 80%, and 100% water holding capacity - WHC) and five temperature levels (10, 17, 24, 31, and 38°C). Under each moisture treatment, Rh was measured several times for each temperature treatment to derive Q10 based on the exponential relationships between Rh and temperature. Microbial biomass carbon (MBC), microbial community structure and soil nutrients were also measured several times to detect their potential contributions to the moisture-induced Q10 variation. We found that Q10 was significantly lower at lower moisture levels (60%, 40% and 20% WHC) than at higher moisture level (80% WHC) during the early stage of the incubation, but became significantly higher at 20%WHC than at 60% WHC and not significantly different from the other three moisture levels during the late stage of incubation. In contrast, soil Rh had the highest value at 60% WHC and the lowest at 20% WHC throughout the whole incubation period. Variations of Q10 were significantly associated with MBC during the early stages of incubation, but with the fungi-to-bacteria ratio during the later stages, suggesting that changes in microbial biomass and community structure are related to the moisture-induced Q10 changes. This study implies that global warming’s impacts on soil CO2 emission may depend upon soil moisture conditions. With the same temperature rise, wetter soils may emit more CO2 into the atmosphere via heterotrophic respiration.
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Affiliation(s)
- Weiping Zhou
- Key laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Graduate University of the Chinese Academy of Sciences, Beijing, PR China
| | - Dafeng Hui
- Department of Biological Sciences, Tennessee State University, Nashville, Tennessee, United States of America
| | - Weijun Shen
- Key laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- * E-mail:
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Nianpeng H, Ruomeng W, Yang G, Jingzhong D, Xuefa W, Guirui Y. Changes in the temperature sensitivity of SOM decomposition with grassland succession: implications for soil C sequestration. Ecol Evol 2013; 3:5045-54. [PMID: 24455135 PMCID: PMC3892367 DOI: 10.1002/ece3.881] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 10/11/2013] [Accepted: 10/15/2013] [Indexed: 11/10/2022] Open
Abstract
Understanding the temperature sensitivity (Q 10) of soil organic matter (SOM) decomposition is important for predicting soil carbon (C) sequestration in terrestrial ecosystems under warming scenarios. Whether Q 10 varies predictably with ecosystem succession and the ways in which the stoichiometry of input SOM influences Q 10 remain largely unknown. We investigate these issues using a grassland succession series from free-grazing to 31-year grazing-exclusion grasslands in Inner Mongolia, and an incubation experiment performed at six temperatures (0, 5, 10, 15, 20, and 25°C) and with four substrates: control (CK), glucose (GLU), mixed grass leaf (GRA), and Medicago falcata leaf (MED). The results showed that basal soil respiration (20°C) and microbial biomass C (MBC) logarithmically decreased with grassland succession. Q 10 decreased logarithmically from 1.43 in free-grazing grasslands to 1.22 in 31-year grazing-exclusion grasslands. Q 10 increased significantly with the addition of substrates, and the Q 10 levels increased with increase in N:C ratios of substrate. Moreover, accumulated C mineralization was controlled by the N:C ratio of newly input SOM and by incubation temperature. Changes in Q 10 with grassland ecosystem succession are controlled by the stoichiometry of newly input SOM, MBC, and SOM quality, and the combined effects of which could partially explain the mechanisms underlying soil C sequestration in the long-term grazing-exclusion grasslands in Inner Mongolia, China. The findings highlight the effect of substrate stoichiometry on Q 10 which requires further study.
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Affiliation(s)
- He Nianpeng
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences Beijing, 100101, China
| | - Wang Ruomeng
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences Beijing, 100101, China
| | - Gao Yang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences Beijing, 100101, China
| | - Dai Jingzhong
- College of Ecology and Environmental Science, Inner Mongolia Agricultural University Hohhot, Inner Mongolia, 010018, China
| | - Wen Xuefa
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences Beijing, 100101, China
| | - Yu Guirui
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences Beijing, 100101, China
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Ecosystem carbon and nitrogen accumulation after grazing exclusion in semiarid grassland. PLoS One 2013; 8:e55433. [PMID: 23383191 PMCID: PMC3559475 DOI: 10.1371/journal.pone.0055433] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 12/23/2012] [Indexed: 11/21/2022] Open
Abstract
The grazing exclusion in degraded grassland has been extensively used to prevent the loss of grassland resources and to improve grassland services. The effects of grazing exclusion on C and N balance, however, have not been well addressed but are essential for assessing grassland C sinks, the sustainable use of grassland resources and the support of grassland services. To understand the response of ecosystem C and N to grazing exclusion in semiarid grassland, we determined the C and N in litter, aboveground biomass, roots and soils from ungrazed grassland fenced at different times in northwest China. Our results showed that the aboveground biomass, root biomass and plant litter were 70–92%, 56–151% and 59–141% higher, respectively, in grazer excluded grassland than in grazed grassland. Grazing exclusion significantly increased C and N stored in plant biomass and litter and increased the concentrations and stocks of C and N in soils. Grazing exclusion thus significantly increased the C and N stored in grassland ecosystems. The increase in C and N stored in soil contributed to more than 95% and 97% of the increases in ecosystem C and N storage. The highest C and N stocks in ecosystems were observed in 17-year grazer excluded grassland. The results from this study indicate that grazing exclusion has the potential to increase C and N storage in degraded semiarid grassland and that the recovery of ecosystem C and N was mainly due to the accumulation of C and N in soils.
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