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Kong L, Song J, Ru J, Feng J, Hou J, Wang X, Zhang Q, Wang H, Yue X, Zhou Z, Sun D, Zhang J, Li H, Fan Y, Wan S. Nitrogen addition does not alter symmetric responses of soil respiration to changing precipitation in a semi-arid grassland. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 921:171170. [PMID: 38402979 DOI: 10.1016/j.scitotenv.2024.171170] [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: 10/30/2023] [Revised: 02/09/2024] [Accepted: 02/20/2024] [Indexed: 02/27/2024]
Abstract
Concurrent changing precipitation regimes and atmospheric nitrogen (N) deposition can have profound influences on soil carbon (C) cycling. However, how N enrichment regulates the responses of soil C fluxes to increasing variability of precipitation remains elusive. As part of a field precipitation gradient experiment with nine levels of precipitation amounts (-60 %, -45 %, -30 %, -15 %, ambient precipitation, +15 %, +30 %, +45 %, and +60 %) and two levels of N addition (0 and 10 g N m-2 yr-1) in a semi-arid temperate steppe on the Mongolian Plateau, this work was conducted to investigate the responses of soil respiration to decreased and increased precipitation (DP and IP), N addition, and their possible interactions. Averaged over the three years from 2019 to 2021, DP suppressed soil respiration by 16.1 %, whereas IP stimulated it by 27.4 %. Nitrogen addition decreased soil respiration by 7.1 % primarily via reducing microbial biomass C. Soil respiration showed symmetric responses to DP and IP within all the four precipitation variabilities (i.e., 15 %, 30 %, 45 %, and 60 %) under ambient N. Nevertheless, N addition did not alter the symmetric responses of soil respiration to changing precipitation due to the comparable sensitivities of microbial biomass and root growth to DP and IP under the N addition treatment. These findings indicate that intensified precipitation variability does not change but N addition could alleviate soil C releases. The unchanged symmetric responses of soil respiration to precipitation variability under N addition imply that N deposition may not change the response pattern of soil C releases to predicted increases in precipitation variability in grasslands, facilitating the robust projections of ecosystem C cycling under future global change scenarios.
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Affiliation(s)
- Lingjie Kong
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Jian Song
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Jingyi Ru
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Jiayin Feng
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Jiawei Hou
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Xueke Wang
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Qingshan Zhang
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Haidao Wang
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Xiaojing Yue
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Zhenxing Zhou
- International Joint Research Laboratory for Global Change Ecology, School of Life Sciences, Henan University, Kaifeng, Henan 475004, China
| | - Dasheng Sun
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Jiajia Zhang
- International Joint Research Laboratory for Global Change Ecology, School of Life Sciences, Henan University, Kaifeng, Henan 475004, China
| | - Heng Li
- International Joint Research Laboratory for Global Change Ecology, School of Life Sciences, Henan University, Kaifeng, Henan 475004, China
| | - Yongge Fan
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China
| | - Shiqiang Wan
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei 071002, China.
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Xiao S, Wang C, Yu K, Liu G, Wu S, Wang J, Niu S, Zou J, Liu S. Enhanced CO 2 uptake is marginally offset by altered fluxes of non-CO 2 greenhouse gases in global forests and grasslands under N deposition. GLOBAL CHANGE BIOLOGY 2023; 29:5829-5849. [PMID: 37485988 DOI: 10.1111/gcb.16869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 06/01/2023] [Indexed: 07/25/2023]
Abstract
Despite the increasing impact of atmospheric nitrogen (N) deposition on terrestrial greenhouse gas (GHG) budget, through driving both the net atmospheric CO2 exchange and the emission or uptake of non-CO2 GHGs (CH4 and N2 O), few studies have assessed the climatic impact of forests and grasslands under N deposition globally based on different bottom-up approaches. Here, we quantify the effects of N deposition on biomass C increment, soil organic C (SOC), CH4 and N2 O fluxes and, ultimately, the net ecosystem GHG balance of forests and grasslands using a global comprehensive dataset. We showed that N addition significantly increased plant C uptake (net primary production) in forests and grasslands, to a larger extent for the aboveground C (aboveground net primary production), whereas it only caused a small or insignificant enhancement of SOC pool in both upland systems. Nitrogen addition had no significant effect on soil heterotrophic respiration (RH ) in both forests and grasslands, while a significant N-induced increase in soil CO2 fluxes (RS , soil respiration) was observed in grasslands. Nitrogen addition significantly stimulated soil N2 O fluxes in forests (76%), to a larger extent in grasslands (87%), but showed a consistent trend to decrease soil uptake of CH4 , suggesting a declined sink capacity of forests and grasslands for atmospheric CH4 under N enrichment. Overall, the net GHG balance estimated by the net ecosystem production-based method (forest, 1.28 Pg CO2 -eq year-1 vs. grassland, 0.58 Pg CO2 -eq year-1 ) was greater than those estimated using the SOC-based method (forest, 0.32 Pg CO2 -eq year-1 vs. grassland, 0.18 Pg CO2 -eq year-1 ) caused by N addition. Our findings revealed that the enhanced soil C sequestration by N addition in global forests and grasslands could be only marginally offset (1.5%-4.8%) by the combined effects of its stimulation of N2 O emissions together with the reduced soil uptake of CH4 .
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Affiliation(s)
- Shuqi Xiao
- Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation, Nanjing, China
| | - Chao Wang
- Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation, Nanjing, China
| | - Kai Yu
- Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation, Nanjing, China
| | - Genyuan Liu
- Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation, Nanjing, China
| | - Shuang Wu
- Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation, Nanjing, China
- Key Laboratory of Low-carbon and Green Agriculture in Southeastern China, Ministry of Agriculture and Rural Affairs, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
| | - Jinyang Wang
- Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation, Nanjing, China
- Key Laboratory of Low-carbon and Green Agriculture in Southeastern China, Ministry of Agriculture and Rural Affairs, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
| | - Shuli Niu
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Jianwen Zou
- Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation, Nanjing, China
- Key Laboratory of Low-carbon and Green Agriculture in Southeastern China, Ministry of Agriculture and Rural Affairs, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- Jiangsu Key Lab and Engineering Center for Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, China
| | - Shuwei Liu
- Jiangsu Key Laboratory of Low Carbon Agriculture and GHGs Mitigation, Nanjing, China
- Key Laboratory of Low-carbon and Green Agriculture in Southeastern China, Ministry of Agriculture and Rural Affairs, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China
- Jiangsu Key Lab and Engineering Center for Solid Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, China
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3
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Li C, Valencia E, Shi Y, Zhou G, Li X. N 2-fixing bacteria are more sensitive to microtopography than nitrogen addition in degraded grassland. Front Microbiol 2023; 14:1240634. [PMID: 37779719 PMCID: PMC10540685 DOI: 10.3389/fmicb.2023.1240634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 08/25/2023] [Indexed: 10/03/2023] Open
Abstract
Introduction Soil bacteria play a crucial role in the terrestrial nitrogen (N) cycle by fixing atmospheric N2, and this process is influenced by both biotic and abiotic factors. The diversity of N2-fixing bacteria (NFB) directly reflects the efficiency of soil N fixation, and the diversity of NFB in degraded alpine meadow soil may change with different N fertilizing levels and varied slopes. However, how N addition affects the diversity of NFB in degraded alpine meadows, and whether this influence varies with slope, remain poorly understood. Methods We conducted an N addition field experiment at three levels (2, 5, and 10 g N·m-2·a-1) to study the effects of N addition on soil NFB diversity on two different slopes in a degraded meadow on the Tibetan Plateau. Results There were significant differences in the dominant bacterial species between the two slopes. The Chao1 index, species richness, and beta diversity of NFB did not differ significantly between slopes, but the Shannon index did. Interestingly, N addition had no effect on the diversity of NFB or the abundance of dominant bacteria. However, we did observe a significant change in some low-abundance NFB. The community composition and diversity of NFB were significantly positively correlated with slope and soil physicochemical properties (e.g., total potassium, pH, and total nitrogen). Conclusions Our study highlights the variation in NFB communities among different slopes in degraded alpine meadows and their resilience to exogenous N addition. Our results also underscore the importance of considering the effects of micro-topography on soil microbial communities in future studies of alpine ecosystems.
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Affiliation(s)
- Chengyi Li
- College of Agriculture and Animal Husbandry, Qinghai University, Xining, China
| | - Enrique Valencia
- Departamento de Biodiversidad, Ecología y Evolución, Facultad de Ciencias Biológicas, Universidad Complutense de Madrid, Madrid, Spain
| | - Yan Shi
- School of Environment, The University of Auckland, Auckland, New Zealand
| | - Guiyao Zhou
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
- Institute of Biology, Leipzig University, Leipzig, Germany
| | - Xilai Li
- College of Agriculture and Animal Husbandry, Qinghai University, Xining, China
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Du Y, Wang YP, Hui D, Su F, Yan J. Significant effects of precipitation frequency on soil respiration and its components-A global synthesis. GLOBAL CHANGE BIOLOGY 2023; 29:1188-1205. [PMID: 36408676 DOI: 10.1111/gcb.16532] [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: 06/16/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
Global warming intensifies the hydrological cycle, which results in changes in precipitation regime (frequency and amount), and will likely have significant impacts on soil respiration (Rs ). Although the responses of Rs to changes in precipitation amount have been extensively studied, there is little consensus on how Rs will be affected by changes in precipitation frequency (PF) across the globe. Here, we synthesized the field observations from 296 published papers to quantify the effects of PF on Rs and its components using meta-analysis. Our results indicated that the effects of PF on Rs decreased with an increase in background mean annual precipitation. When the data were grouped by climate conditions, increased PF showed positive effects on Rs under the arid condition but not under the semi-humid or humid conditions, whereas decreased PF suppressed Rs across all the climate conditions. The positive effects of increased PF mainly resulted from the positive response of heterotrophic respiration under the arid condition while the negative effects of decreased PF were mainly attributed to the reductions in root biomass and respiration. Overall, our global synthesis provided for the first time a comprehensive analysis of the divergent effects of PF on Rs and its components across climate regions. This study also provided a framework for understanding and modeling responses of ecosystem carbon cycling to global precipitation change.
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Affiliation(s)
- Yue Du
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- College of Geography and Environmental Science, Henan University, Kaifeng, China
| | - Ying-Ping Wang
- CSIRO Oceans and Atmosphere, Aspendale, Victoria, Australia
| | - Dafeng Hui
- Department of Biological Sciences, Tennessee State University, Nashville, Tennessee, USA
| | - Fanglong Su
- School of Life Sciences, Henan University, Kaifeng, China
| | - Junhua Yan
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
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Yu J, Zhang Y, Wang Y, Luo X, Liang X, Huang X, Zhao Y, Zhou X, Li J. Ecosystem photosynthesis depends on increased water availability to enhance carbon assimilation in semiarid desert steppe in northern China. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2022.e02202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Zhang J, Ru J, Song J, Li H, Li X, Ma Y, Li Z, Hao Y, Chi Z, Hui D, Wan S. Increased precipitation and nitrogen addition accelerate the temporal increase in soil respiration during 8-year old-field grassland succession. GLOBAL CHANGE BIOLOGY 2022; 28:3944-3959. [PMID: 35274404 DOI: 10.1111/gcb.16159] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 02/04/2022] [Indexed: 05/16/2023]
Abstract
Ecological succession after disturbance plays a vital role in influencing ecosystem structure and functioning. However, how global change factors regulate ecosystem carbon (C) cycling in successional plant communities remains largely elusive. As part of an 8-year (2012-2019) manipulative experiment, this study was designed to examine the responses of soil respiration and its heterotrophic component to simulated increases in precipitation and atmospheric nitrogen (N) deposition in an old-field grassland undergoing secondary succession. Over the 8-year experimental period, increased precipitation stimulated soil respiration by 11.6%, but did not affect soil heterotrophic respiration. Nitrogen addition increased both soil respiration (5.1%) and heterotrophic respiration (6.2%). Soil respiration and heterotrophic respiration linearly increased with time in the control plots, resulting from changes in soil moisture and shifts of plant community composition from grass-forb codominance to grass dominance in this old-field grassland. Compared to the control, increased precipitation significantly strengthened the temporal increase in soil respiration through stimulating belowground net primary productivity. By contrast, N addition accelerated temporal increases in both soil respiration and its heterotrophic component by driving plant community shifts and thus stimulating soil organic C. Our findings indicate that increases in water and N availabilities may accelerate soil C release during old-field grassland succession and reduce their potential positive impacts on soil C accumulation under future climate change scenarios.
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Affiliation(s)
- Jiajia Zhang
- School of Life Sciences, Henan University, Kaifeng, Henan, China
| | - Jingyi Ru
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei, China
| | - Jian Song
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei, China
| | - Heng Li
- School of Life Sciences, Henan University, Kaifeng, Henan, China
| | - Xiaoming Li
- School of Life Sciences, Henan University, Kaifeng, Henan, China
| | - Yafei Ma
- School of Life Sciences, Henan University, Kaifeng, Henan, China
| | - Zheng Li
- School of Life Sciences, Henan University, Kaifeng, Henan, China
| | - Yuanfeng Hao
- School of Life Sciences, Henan University, Kaifeng, Henan, China
| | - Zhensheng Chi
- School of Life Sciences, Henan University, Kaifeng, Henan, China
| | - Dafeng Hui
- Department of Biological Sciences, Tennessee State University, Nashville, Tennessee, USA
| | - Shiqiang Wan
- School of Life Sciences, Henan University, Kaifeng, Henan, China
- School of Life Sciences, Institute of Life Science and Green Development, Hebei University, Baoding, Hebei, China
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Yu B, Rossi S, Liang H, Guo X, Ma Q, Zhang S, Kang J, Zhao P, Zhang W, Ju Y, Huang JG. Effects of nitrogen addition and increased precipitation on xylem growth of Quercus acutissima Caruth. in central China. TREE PHYSIOLOGY 2022; 42:754-770. [PMID: 35029689 DOI: 10.1093/treephys/tpab152] [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: 08/20/2021] [Accepted: 11/11/2021] [Indexed: 06/14/2023]
Abstract
Atmospheric nitrogen (N) deposition and increasing precipitation affect carbon sequestration in terrestrial ecosystems, but how these two concurrent global change variables affect xylem growth in trees (i.e., independently or interactively) remains unclear. We conducted novel experiments in central China to monitor the xylem growth in a dominant species (Quercus acutissima Caruth.) in response to N addition (CN), supplemental precipitation (CW) or both treatments (CNW), compared with untreated controls (C). Measurements were made at weekly intervals during 2014-15. We found that supplemental precipitation significantly enhanced xylem growth in the dry spring of 2015, indicating a time-varying effect of increased precipitation on intra-annual xylem growth. Elevated N had no significant effect on xylem increment, xylem growth rate, and lumen diameters and potential hydraulic conductivity (Ks) of earlywood vessels, but Ks with elevated N was significantly negatively related to xylem increment. The combination of additional N and supplemental precipitation suppressed the positive effect of supplemental precipitation on xylem increment in the dry spring of 2015. These findings indicated that xylem width was more responsive to supplemental precipitation than to increasing N in a dry early growing season; the positive effect of supplemental precipitation on xylem growth could be offset by elevated N resources. The negative interactive effect of N addition and supplemental precipitation also suggested that increasing N deposition and precipitation in the future might potentially affect carbon sequestration of Q. acutissima during the early growing season in central China. The effects of N addition and supplemental precipitation on tree growth are complex and might vary depending on the growth period and local climatic conditions. Therefore, future models of tree growth need to consider multiple-time scales and local climatic conditions when simulating and projecting global change.
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Affiliation(s)
- Biyun Yu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou 510650, China
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sergio Rossi
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Département des Sciences Fondamentales, Université du Québec à Chicoutimi, Chicoutimi, QC G7H 2B1, Canada
| | - Hanxue Liang
- Institute of Loess Plateau, Shanxi University, Taiyuan 030006, China
| | - Xiali Guo
- College of Forestry, Guangxi University, Nanning 530004, China
| | - Qianqian Ma
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou 510650, China
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Shaokang Zhang
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou 510650, China
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Jian Kang
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ping Zhao
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou 510650, China
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Zhang
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Yuxi Ju
- Jigongshan National Natural Reserve, Xinyang 464000, China
| | - Jian-Guo Huang
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou 510650, China
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Su F, Wang F, Li Z, Wei Y, Li S, Bai T, Wang Y, Guo H, Hu S. Predominant role of soil moisture in regulating the response of ecosystem carbon fluxes to global change factors in a semi-arid grassland on the Loess Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 738:139746. [PMID: 32531591 DOI: 10.1016/j.scitotenv.2020.139746] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 05/21/2020] [Accepted: 05/25/2020] [Indexed: 06/11/2023]
Abstract
Climate warming, altered precipitation and nitrogen deposition may critically affect plant growth and ecosystem carbon fluxes. However, the underlying mechanisms are not fully understood. We conducted a 2-yr, multi-factor experiment (warming (W), altered precipitation (+30% and - 30%) and nitrogen addition (N)) in a semi-arid grassland on the Loess Plateau to study how these factors affect ecosystem carbon fluxes. Surprisingly, no interactive effects of warming, altered precipitation and nitrogen addition were detected on parameters of ecosystem carbon fluxes, including net ecosystem CO2 exchange (NEE), ecosystem respiration (ER), gross ecosystem productivity (GEP) and soil respiration (SR). Warming marginally reduced NEE and GEP mainly due to its negative effects on them in July and August. Altered precipitation significantly affected all parameters of carbon fluxes with precipitation reduction decreasing NEE, ER and GEP, whereas precipitation addition increasing SR. In contrast, nitrogen addition had little effect on any parameters of carbon fluxes. Soil moisture was the most important driver and positively correlated with ecosystem carbon fluxes and warming impacted ecosystem carbon fluxes indirectly by decreasing soil moisture. While plant community cover did not show significant association with carbon fluxes, semi-shrubs cover was positively related to NEE, ER and GEP. Together, these results suggest that soil water availability, rather than soil temperature and nitrogen availability, may dominate the effect of the future multi-faceted global changes on semi-arid grassland carbon fluxes on the Loess Plateau.
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Affiliation(s)
- Fanglong Su
- Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Fuwei Wang
- Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Zhen Li
- Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Yanan Wei
- Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Shijie Li
- Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Tongshuo Bai
- Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
| | - Yi Wang
- State Key Laboratory of Loess and Quaternary, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, People's Republic of China
| | - Hui Guo
- Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
| | - Shuijin Hu
- Ecosystem Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China; Department of Entomology & Plant Pathology, North Carolina State University, Raleigh, NC 27695, USA.
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9
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Wang Z, Mckenna TP, Schellenberg MP, Tang S, Zhang Y, Ta N, Na R, Wang H. Soil respiration response to alterations in precipitation and nitrogen addition in a desert steppe in northern China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 688:231-242. [PMID: 31229820 DOI: 10.1016/j.scitotenv.2019.05.419] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 05/27/2019] [Accepted: 05/27/2019] [Indexed: 06/09/2023]
Abstract
Global climate change is expected to significantly influence soil respiration. When limited, rainfall and nitrogen (N) deposition strongly modify soil respiration in a broad range of biomes, but uncertainty remains with regards to the influence of the interactions of seasonal rainfall distribution and N deposition on soil respiration in an arid steppe. In the present study, we manipulated precipitation using V-shaped plexiglass gutters (minus 50%, control, and plus 50% treatments) and tested various N additions (control and plus 35 kg N ha-1 yr-1) to evaluate their impact on soil respiration, measured using a Li-Cor 8100, in a desert steppe in China. Increased precipitation stimulated soil respiration by 26.1%, while decreased precipitation significantly reduced soil respiration by 10.8%. There was a significant increase in soil respiration under N addition at 11.5%. Statistical assessment of their interactions demonstrated that N supplementation strengthened the stimulation of soil respiration under increased precipitation, whereas decreased precipitation offset the positive impact of N addition and led to a reduction in soil respiration. Contrasting interannual precipitation patterns strongly influenced the temporal changes in soil respiration as well as its response to N addition, indicating that the desert steppe plant community was co-limited by water and N. Net primary productivity (aboveground and belowground) predominantly drove soil respiration under altered precipitation and N addition. As grasses are better equipped for water deficit due to their previous exposure to long periods without water, there could be a shift from forb to grass communities under drier conditions. These findings highlight the importance of assessing the differential impacts of plant traits and soil physiochemical properties on soil respiration under altered precipitation and N addition.
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Affiliation(s)
- Zhen Wang
- Grassland Research Institute, Chinese Academy of Agricultural Sciences, Hohhot 010010, China
| | - Thomas P Mckenna
- Department of Ecology and Evolutionary Biology, The Kansas Biological Survey University of Kansas, Lawrence, KS 66047, United States of America
| | - Michael P Schellenberg
- Swift Current Research and Development Centre (SCRDC), AAFC-AAC, Box 1030, Swift Current, Saskatchewan S9H 3X2, Canada
| | - Shiming Tang
- Department of Ecology, School of Ecology and Environment, Inner Mongolia University, No. 235 West College Road, 010021 Hohhot, China
| | - Yujuan Zhang
- Grassland Research Institute, Chinese Academy of Agricultural Sciences, Hohhot 010010, China
| | - Na Ta
- Grassland Research Institute, Chinese Academy of Agricultural Sciences, Hohhot 010010, China
| | - Risu Na
- Grassland Research Institute, Chinese Academy of Agricultural Sciences, Hohhot 010010, China.
| | - Hai Wang
- Grassland Research Institute, Chinese Academy of Agricultural Sciences, Hohhot 010010, China.
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10
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Han H, Du Y, Hui D, Jiang L, Zhong M, Wan S. Long-term antagonistic effect of increased precipitation and nitrogen addition on soil respiration in a semiarid steppe. Ecol Evol 2017; 7:10804-10814. [PMID: 29299259 PMCID: PMC5743642 DOI: 10.1002/ece3.3536] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 09/02/2017] [Accepted: 09/16/2017] [Indexed: 11/10/2022] Open
Abstract
Changes in water and nitrogen (N) availability due to climate change and atmospheric N deposition could have significant effects on soil respiration, a major pathway of carbon (C) loss from terrestrial ecosystems. A manipulative experiment simulating increased precipitation and atmospheric N deposition has been conducted for 9 years (2005-2013) in a semiarid grassland in Mongolian Plateau, China. Increased precipitation and N addition interactively affect soil respiration through the 9 years. The interactions demonstrated that N addition weakened the precipitation-induced stimulation of soil respiration, whereas increased precipitation exacerbated the negative impacts of N addition. The main effects of increased precipitation and N addition treatment on soil respiration were 15.8% stimulated and 14.2% suppressed, respectively. Moreover, a declining pattern and 2-year oscillation were observed for soil respiration response to N addition under increased precipitation. The dependence of soil respiration upon gross primary productivity and soil moisture, but not soil temperature, suggests that resources C substrate supply and water availability are more important than temperature in regulating interannual variations of soil C release in semiarid grassland ecosystems. The findings indicate that atmospheric N deposition may have the potential to mitigate soil C loss induced by increased precipitation, and highlight that long-term and multi-factor global change studies are critical for predicting the general patterns of terrestrial C cycling in response to global change in the future.
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Affiliation(s)
- Hongyan Han
- International Joint Research Laboratory for Global Change Ecology School of Life Sciences Henan University Kaifeng Henan China
| | - Yue Du
- College of Life Sciences University of Chinese Academy of Sciences Beijing China
| | - Dafeng Hui
- International Joint Research Laboratory for Global Change Ecology School of Life Sciences Henan University Kaifeng Henan China.,Department of Biological Sciences Tennessee State University Nashville TN USA
| | - Lin Jiang
- School of Biology Georgia Institute of Technology Atlanta GA USA
| | - Mingxing Zhong
- International Joint Research Laboratory for Global Change Ecology School of Life Sciences Henan University Kaifeng Henan China
| | - Shiqiang Wan
- International Joint Research Laboratory for Global Change Ecology School of Life Sciences Henan University Kaifeng Henan China
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