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Filonchyk M, Peterson MP, Zhang L, Hurynovich V, He Y. Greenhouse gases emissions and global climate change: Examining the influence of CO 2, CH 4, and N 2O. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 935:173359. [PMID: 38768722 DOI: 10.1016/j.scitotenv.2024.173359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 05/05/2024] [Accepted: 05/17/2024] [Indexed: 05/22/2024]
Abstract
An in-depth analysis of the role of greenhouse gases (GHGs) in climate change is examined here along with their diverse sources, including the combustion of fossil fuels, agriculture, and industrial processes. Key GHG components such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) are considered, along with data on emissions across various economic sectors. The consequences of climate change are also highlighted, ranging from more frequent and intense extreme weather events to rising sea levels and impacts on ecosystems and human health. The industrial revolution and unrestricted use of fossil fuels are key factors leading to an increase in GHG concentrations in the atmosphere. Global efforts to reduce emissions are considered, starting with the 1997 Kyoto Protocol and culminating in the 2015 Paris Agreement. The limited effectiveness of early initiatives is underscored, emphasizing the significant importance of the Paris Agreement that provides a global framework for establishing goals to reduce GHG emissions by country. The Green Climate Fund and other international financial mechanisms are also considered as essential tools for financing sustainable projects in developing countries. The global community faces the challenge and necessity for more ambitious efforts to achieve the set goals for reducing GHG emissions. Successful strategies are examined by Sweden, Costa Rica, and Denmark to achieve zero GHG emissions that integrate renewable energy sources and technologies. The importance of global cooperation for creating a sustainable future is also emphasized.
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Affiliation(s)
- Mikalai Filonchyk
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring, Lanzhou 730070, Gansu, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China.
| | - Michael P Peterson
- Department of Geography/Geology, University of Nebraska Omaha, Omaha, NE 68182, USA
| | - Lifeng Zhang
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring, Lanzhou 730070, Gansu, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China
| | - Volha Hurynovich
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring, Lanzhou 730070, Gansu, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China
| | - Yi He
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring, Lanzhou 730070, Gansu, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China
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Ji Y, Zeng S, Liu X, Xia J. Mutual inhibition effects of elevated CO 2 and climate change on global forest GPP. ENVIRONMENTAL RESEARCH 2024; 252:119145. [PMID: 38754610 DOI: 10.1016/j.envres.2024.119145] [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: 03/07/2024] [Revised: 05/12/2024] [Accepted: 05/13/2024] [Indexed: 05/18/2024]
Abstract
The impact of CO2 fertilization on enhancing global forest gross primary productivity (GPP) is acknowledged, but its interaction with climate factors-air temperature (Tem), precipitation (Pre), vapor pressure deficit (VPD), and radiation (Rad)-remains unclear. In this study, global forest GPP trends from 1982 to 2018 were examined using BEPS, NIRv, FLUXCOM, and revised EC-LUE datasets, with interannual trends of 5.618 (p < 0.01), 5.831 (p < 0.01), 0.227, and 6.566 g C m-2 yr-1 (p < 0.01), respectively. Elevated CO2 was identified as the primary driver of GPP trends, with the dominant area ranging from 51.11% to 90.37% across different GPP datasets. In the NIRv and revised EC-LUE datasets, the positive impact of CO2 on GPP showed a decrease of 0.222 g C m-2 yr-1, while the negative impact of Rad increased by 0.007 g C m-2 yr-1. An inhibitory relationship was found between the actual effects of elevated CO2 and climate change on GPP in most forest types. At lower latitudes, Tem primarily constrained CO2 fertilization, while at higher latitudes, VPD emerged as the key limiting factor. This was mainly attributed to the potential trade-off or competition between elevated CO2 and climate change in influencing GPP, with strategic resource allocation varying across different forest ecosystems. This study highlights the significant inhibitory effects of elevated CO2 and climate change on global forest GPP, providing insights into the dynamic responses of forest ecosystems to changing environments.
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Affiliation(s)
- Yongyue Ji
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China; Chongqing School, University of Chinese Academy of Sciences, Chongqing, 400714, China
| | - Sidong Zeng
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China; Chongqing School, University of Chinese Academy of Sciences, Chongqing, 400714, China.
| | - Xin Liu
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China; Chongqing School, University of Chinese Academy of Sciences, Chongqing, 400714, China
| | - Jun Xia
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, 430072, China
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Pan Y, Birdsey RA, Phillips OL, Houghton RA, Fang J, Kauppi PE, Keith H, Kurz WA, Ito A, Lewis SL, Nabuurs GJ, Shvidenko A, Hashimoto S, Lerink B, Schepaschenko D, Castanho A, Murdiyarso D. The enduring world forest carbon sink. Nature 2024; 631:563-569. [PMID: 39020035 DOI: 10.1038/s41586-024-07602-x] [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: 05/22/2023] [Accepted: 05/24/2024] [Indexed: 07/19/2024]
Abstract
The uptake of carbon dioxide (CO2) by terrestrial ecosystems is critical for moderating climate change1. To provide a ground-based long-term assessment of the contribution of forests to terrestrial CO2 uptake, we synthesized in situ forest data from boreal, temperate and tropical biomes spanning three decades. We found that the carbon sink in global forests was steady, at 3.6 ± 0.4 Pg C yr-1 in the 1990s and 2000s, and 3.5 ± 0.4 Pg C yr-1 in the 2010s. Despite this global stability, our analysis revealed some major biome-level changes. Carbon sinks have increased in temperate (+30 ± 5%) and tropical regrowth (+29 ± 8%) forests owing to increases in forest area, but they decreased in boreal (-36 ± 6%) and tropical intact (-31 ± 7%) forests, as a result of intensified disturbances and losses in intact forest area, respectively. Mass-balance studies indicate that the global land carbon sink has increased2, implying an increase in the non-forest-land carbon sink. The global forest sink is equivalent to almost half of fossil-fuel emissions (7.8 ± 0.4 Pg C yr-1 in 1990-2019). However, two-thirds of the benefit from the sink has been negated by tropical deforestation (2.2 ± 0.5 Pg C yr-1 in 1990-2019). Although the global forest sink has endured undiminished for three decades, despite regional variations, it could be weakened by ageing forests, continuing deforestation and further intensification of disturbance regimes1. To protect the carbon sink, land management policies are needed to limit deforestation, promote forest restoration and improve timber-harvesting practices1,3.
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Affiliation(s)
- Yude Pan
- USDA Forest Service, Durham, NH, USA.
| | | | | | | | | | - Pekka E Kauppi
- Department of Forest Sciences, University of Helsinki, Helsinki, Finland
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Heather Keith
- Climate Action Beacon, Griffith University, Gold Coast, Australia
| | - Werner A Kurz
- Natural Resources Canada, Canadian Forest Service, Victoria, Canada
| | | | - Simon L Lewis
- School of Geography, University of Leeds, Leeds, UK
- Department of Geography, University College London, London, UK
| | - Gert-Jan Nabuurs
- Wageningen Environmental Research, Wageningen University & Research, Wageningen, Netherlands
- Forest Ecology and Forest Management Group, Wageningen University & Research, Wageningen, Netherlands
| | - Anatoly Shvidenko
- International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria
| | - Shoji Hashimoto
- The University of Tokyo, Tokyo, Japan
- Forestry and Forest Products Research Institute, Tsukuba, Japan
| | - Bas Lerink
- Wageningen Environmental Research, Wageningen University & Research, Wageningen, Netherlands
| | - Dmitry Schepaschenko
- International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria
| | | | - Daniel Murdiyarso
- Department of Geophysics and Meteorology, IPB University, Bogor, Indonesia
- Center for International Forestry Research - World Agroforestry, Bogor, Indonesia
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Zhang-Zheng H, Adu-Bredu S, Duah-Gyamfi A, Moore S, Addo-Danso SD, Amissah L, Valentini R, Djagbletey G, Anim-Adjei K, Quansah J, Sarpong B, Owusu-Afriyie K, Gvozdevaite A, Tang M, Ruiz-Jaen MC, Ibrahim F, Girardin CAJ, Rifai S, Dahlsjö CAL, Riutta T, Deng X, Sun Y, Prentice IC, Oliveras Menor I, Malhi Y. Contrasting carbon cycle along tropical forest aridity gradients in West Africa and Amazonia. Nat Commun 2024; 15:3158. [PMID: 38605006 PMCID: PMC11009382 DOI: 10.1038/s41467-024-47202-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Accepted: 03/22/2024] [Indexed: 04/13/2024] Open
Abstract
Tropical forests cover large areas of equatorial Africa and play a substantial role in the global carbon cycle. However, there has been a lack of biometric measurements to understand the forests' gross and net primary productivity (GPP, NPP) and their allocation. Here we present a detailed field assessment of the carbon budget of multiple forest sites in Africa, by monitoring 14 one-hectare plots along an aridity gradient in Ghana, West Africa. When compared with an equivalent aridity gradient in Amazonia, the studied West African forests generally had higher productivity and lower carbon use efficiency (CUE). The West African aridity gradient consistently shows the highest NPP, CUE, GPP, and autotrophic respiration at a medium-aridity site, Bobiri. Notably, NPP and GPP of the site are the highest yet reported anywhere for intact forests. Widely used data products substantially underestimate productivity when compared to biometric measurements in Amazonia and Africa. Our analysis suggests that the high productivity of the African forests is linked to their large GPP allocation to canopy and semi-deciduous characteristics.
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Affiliation(s)
- Huanyuan Zhang-Zheng
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, United Kingdom.
- Leverhulme Centre for Nature Recovery, University of Oxford, Oxford, United Kingdom.
| | - Stephen Adu-Bredu
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, Kumasi, Ghana
- Department of Natural Resources Management, CSIR College of Science and Technology, Kumasi, Ghana
| | - Akwasi Duah-Gyamfi
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, Kumasi, Ghana
| | - Sam Moore
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, United Kingdom
| | - Shalom D Addo-Danso
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, Kumasi, Ghana
| | - Lucy Amissah
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, Kumasi, Ghana
| | | | - Gloria Djagbletey
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, Kumasi, Ghana
| | - Kelvin Anim-Adjei
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, Kumasi, Ghana
| | - John Quansah
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, Kumasi, Ghana
| | - Bernice Sarpong
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, Kumasi, Ghana
| | - Kennedy Owusu-Afriyie
- Forestry Research Institute of Ghana, Council for Scientific and Industrial Research, Kumasi, Ghana
| | - Agne Gvozdevaite
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, United Kingdom
| | - Minxue Tang
- Georgina Mace Centre for the Living Planet, Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, United Kingdom
| | - Maria C Ruiz-Jaen
- Forestry Division, Food and Agriculture Organization of the United Nations, Panama City, Panama
| | - Forzia Ibrahim
- Department of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Praha, Czech Republic
| | - Cécile A J Girardin
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, United Kingdom
| | - Sami Rifai
- School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Cecilia A L Dahlsjö
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, United Kingdom
| | - Terhi Riutta
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, United Kingdom
| | - Xiongjie Deng
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, United Kingdom
| | - Yuheng Sun
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, P.O. Box 11103, 9700 CC, Groningen, The Netherlands
| | - Iain Colin Prentice
- Georgina Mace Centre for the Living Planet, Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, United Kingdom
- Department of Earth System Science, Ministry of Education Key Laboratory for Earth System Modeling, Institute for Global Change Studies, Tsinghua University, Beijing, China
| | - Imma Oliveras Menor
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, United Kingdom
- AMAP (Botanique et Modelisation de l'Architecture des Plantes et des Végétations), CIRAD, CNRS, INRA, IRD,Université de Montpellier, Montpellier, France
| | - Yadvinder Malhi
- Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, United Kingdom.
- Leverhulme Centre for Nature Recovery, University of Oxford, Oxford, United Kingdom.
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Bejagam V, Sharma A, Wei X. Projected decline in the strength of vegetation carbon sequestration under climate change in India. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170166. [PMID: 38253099 DOI: 10.1016/j.scitotenv.2024.170166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/07/2024] [Accepted: 01/12/2024] [Indexed: 01/24/2024]
Abstract
Tropical vegetation plays a critical role in terrestrial carbon budget and supply many ecological functions such as carbon sequestration. In recent decades, India has witnessed an increase in net primary productivity (NPP), an important measure of carbon sequestration. However, uncertainties persist regarding the sustainability of these land carbon sinks in the face of climate change. The enhanced NPP is driven by the strong CO2 fertilization effect (CFE), but the temporal patterns of this feedback remain unclear. Using the carbon flux data from the Earth System Models (ESMs), an increasing trend in NPP was observed, with projections of NPP to 2.00 ± 0.12 PgCyr-1 (25 % increase) during 2021-2049, 2.36 ± 0.12 PgCyr-1 (18 % increase) during 2050-2079, and 2.67 ± 0.07 PgCyr-1 (13 % increase) during 2080-2099 in Indian vegetation under SSP585 scenario. This suggests a significant decline in the NPP growth rate. To understand the feedback mechanisms driving NPP, the relative effects of CFE and warming were analyzed. Comparing simulations from the biogeochemically coupled model (BGC) with the fully coupled model, the BGC model projected a 74.7 % increase in NPP, significantly higher than the 55.9 % increase projected by the fully coupled model by the end of the century. This indicates that the consistent increase in NPP was associated with CO2 fertilization. More importantly, results reveal that the decrease in the NPP growth rate was due to the declining contribution of CFE at a rate of -0.62 % per 100 ppm CO2 increase. This decline could be attributed to factors such as nutrient limitations and high temperatures. Additionally, significant shifts in the strength of carbon sinks in offsetting the CO2 emissions were identified, decreasing at a rate of -1.15 % per decade. This decline in the strength of vegetation carbon sequestration may increase the societal dependence on mitigation measures to address climate change.
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Affiliation(s)
- Vijaykumar Bejagam
- Department of Hydrology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India; Department of Earth, Environmental and Geographic Sciences, The University of British Columbia, Okanagan, Kelowna, BC V1V 1V7, Canada
| | - Ashutosh Sharma
- Department of Hydrology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India.
| | - Xiaohua Wei
- Department of Earth, Environmental and Geographic Sciences, The University of British Columbia, Okanagan, Kelowna, BC V1V 1V7, Canada
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Liu Z, Zeng N, Liu Y, Wang J, Han P, Cai Q. Weaker regional carbon uptake albeit with stronger seasonal amplitude in northern mid-latitudes estimated by higher resolution GEOS-Chem model. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169477. [PMID: 38143002 DOI: 10.1016/j.scitotenv.2023.169477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/27/2023] [Accepted: 12/16/2023] [Indexed: 12/26/2023]
Abstract
Terrestrial ecosystem in the Northern Hemisphere is characterized by a substantial carbon sink in recent decades. However, the carbon sink inferred from atmospheric CO2 data is usually larger than process- and inventory-based estimates, resulting in carbon release or near-neutral carbon exchange in the tropics. The atmospheric approach is known to be uncertain due to systematic biases of coarse atmospheric transport model simulation. Compared to a coarse-resolution inverse estimate at 4° × 5° using GEOS-Chem in the integrated region of N. America, E. Asia, and Europe from 2015 to 2018, the annual carbon sink estimate at a native high-resolution of 0.5° × 0.625° is reduced from -3.0±0.08 gigatons of carbon per year (GtC yr-1) to -2.15±0.08 GtC yr-1 due to prominent more carbon release during the non-growing seasons. The major reductions concentrate in the mid-latitudes (20°N-45°N), where the mean land carbon sinks in China and the USA are reduced from 0.64±0.03 and 0.35±0.02 GtC yr-1 to 0.14±0.03 and 0.15±0.02 GtC yr-1, respectively. The coarse-resolution GEOS-Chem tends to trap both the release and uptake signal within the planetary boundary layer, resulting in weaker estimates of biosphere seasonal strength. Since the strong fossil fuel emissions are persistently released from the surface, the trapped signal leads to the stronger estimates of annual carbon uptakes. These results suggest that high-resolution inversion with accurate vertical and meridional transport is urgently needed in targeting national carbon neutrality.
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Affiliation(s)
- Zhiqiang Liu
- CMA Key Open Laboratory of Transforming Climate Resources to Economy, Chongqing Institute of Meteorological Sciences, Chongqing 401147, China.
| | - Ning Zeng
- Dept. of Atmospheric and Oceanic Science, University of Maryland, College Park, Maryland, USA; Earth System Science Interdisciplinary Center, University of Maryland, College Park, Maryland, USA.
| | - Yun Liu
- Geochemical and Environment Research Group, Texas A&M University, College Station, TX, USA
| | - Jun Wang
- International Institute for Earth System Science, Nanjing University, Nanjing, China
| | - Pengfei Han
- Carbon Neutrality Research Center, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China; Laboratory of Numerical Modeling for Atmospheric Sciences & Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
| | - Qixiang Cai
- Laboratory of Numerical Modeling for Atmospheric Sciences & Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
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Chen Z, Wang W, Forzieri G, Cescatti A. Transition from positive to negative indirect CO 2 effects on the vegetation carbon uptake. Nat Commun 2024; 15:1500. [PMID: 38374331 PMCID: PMC10876672 DOI: 10.1038/s41467-024-45957-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Accepted: 02/08/2024] [Indexed: 02/21/2024] Open
Abstract
Although elevated atmospheric CO2 concentration (eCO2) has substantial indirect effects on vegetation carbon uptake via associated climate change, their dynamics remain unclear. Here we investigate how the impacts of eCO2-driven climate change on growing-season gross primary production have changed globally during 1982-2014, using satellite observations and Earth system models, and evaluate their evolution until the year 2100. We show that the initial positive effect of eCO2-induced climate change on vegetation carbon uptake has declined recently, shifting to negative in the early 21st century. Such emerging pattern appears prominent in high latitudes and occurs in combination with a decrease of direct CO2 physiological effect, ultimately resulting in a sharp reduction of the current growth benefits induced by climate warming and CO2 fertilization. Such weakening of the indirect CO2 effect can be partially attributed to the widespread land drying, and it is expected to be further exacerbated under global warming.
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Affiliation(s)
- Zefeng Chen
- National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing, China
- Yangtze Institute for Conservation and Development, Hohai University, Nanjing, China
- College of Hydrology and Water Resources, Hohai University, Nanjing, China
| | - Weiguang Wang
- National Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing, China.
- Yangtze Institute for Conservation and Development, Hohai University, Nanjing, China.
- College of Hydrology and Water Resources, Hohai University, Nanjing, China.
| | - Giovanni Forzieri
- Department of Civil and Environmental Engineering, University of Florence, Florence, Italy
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Gao J, Kennedy DM, McSweeney S. Decadal changes in vegetation cover within coastal dunes at the regional scale in Victoria, SE Australia. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 351:119622. [PMID: 38042079 DOI: 10.1016/j.jenvman.2023.119622] [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: 04/05/2023] [Revised: 11/13/2023] [Accepted: 11/14/2023] [Indexed: 12/04/2023]
Abstract
Vegetation is a critical boundary condition for the stability of coastal dunes. Globally, vegetation cover is increasing on the coast with many dunes being stabilised in the past decades. This pattern is driven by site-specific (e.g., coastal management) and global (e.g., climatic changes) factors. This study examines changes in dune vegetation during the past six decades at the regional scale along the southeast coast of Australia to understand the relative importance of the climate and human interventions in vegetation cover change. A total area of >31,000 ha, comprising 53% of the open coast of Victoria was studied. Since the 1960's, a general trend of dune stabilisation and coastal greening has occurred with total vegetation cover increasing from 61% to 84% coverage until 2020. At the regional scale, the increase in vegetation cover has been primarily driven by both climatic-related drivers, such as rising temperature, elevating CO2 concentrations and declining windiness, and state-wide coastal management interventions (e.g., marram grass planting, fencing, fire control, grazing removal). The only areas where there was a decline in total area of vegetation was where substantial coastal recession had occurred. The decrease in vegetation is a result of a loss of land area rather than a loss of plant biomass over the dunefields. Therefore, it is considered that the overall decadal changes in both climate and coastal management are forcing the dunes toward a more stabilised state at the regional scale. At the same time, compelling local drivers (e.g., storms and local sediment deficiency) can be the most crucial factor to regulate vegetation change and shift dune mobility at the site-specific scale.
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Affiliation(s)
- Jinjuan Gao
- School of Geography, Earth and Atmospheric Sciences, University of Melbourne, Parkville, VIC, Australia.
| | - David M Kennedy
- School of Geography, Earth and Atmospheric Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Sarah McSweeney
- School of Earth and Environment, The University of Canterbury, Upper Riccarton, Christchurch, 8041, New Zealand
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9
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Dobor L, Baldo M, Bílek L, Barka I, Máliš F, Štěpánek P, Hlásny T. The interacting effect of climate change and herbivory can trigger large-scale transformations of European temperate forests. GLOBAL CHANGE BIOLOGY 2024; 30:e17194. [PMID: 38385958 DOI: 10.1111/gcb.17194] [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: 03/02/2023] [Revised: 01/25/2024] [Accepted: 01/25/2024] [Indexed: 02/23/2024]
Abstract
In many regions of Europe, large wild herbivores alter forest community composition through their foraging preferences, hinder the forest's natural adaptive responses to climate change, and reduce ecosystem resilience. We investigated a widespread European forest type, a mixed forest dominated by Picea abies, which has recently experienced an unprecedented level of disturbance across the continent. Using the forest landscape model iLand, we investigated the combined effect of climate change and herbivory on forest structure, composition, and carbon and identified conditions leading to ecosystem transitions on a 300-year timescale. Eight climate change scenarios, driven by Representative Concentration Pathways 4.5 and 8.5, combined with three levels of regeneration browsing, were tested. We found that the persistence of the current level of browsing pressure impedes adaptive changes in community composition and sustains the presence of the vulnerable yet less palatable P. abies. These development trajectories were tortuous, characterized by a high disturbance intensity. On the contrary, reduced herbivory initiated a transformation towards the naturally dominant broadleaved species that was associated with an increased forest carbon and a considerably reduced disturbance. The conditions of RCP4.5 combined with high and moderate browsing levels preserved the forest within its reference range of variability, defining the actual boundaries of resilience. The remaining combinations of browsing and climate change led to ecosystem transitions. Under RCP4.5 with browsing effects excluded, the new equilibrium conditions were achieved within 120 years, whereas the stabilization was delayed by 50-100 years under RCP8.5 with higher browsing intensities. We conclude that forests dominated by P. abies are prone to transitions driven by climate change. However, reducing herbivory can set the forest on a stable and predictable trajectory, whereas sustaining the current browsing levels can lead to heightened disturbance activity, extended transition times, and high variability in the target conditions.
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Affiliation(s)
- Laura Dobor
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Prague 6, Suchdol, Czech Republic
| | - Marco Baldo
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Prague 6, Suchdol, Czech Republic
| | - Lukáš Bílek
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Prague 6, Suchdol, Czech Republic
| | - Ivan Barka
- National Forest Centre - Forest Research Institute Zvolen, Zvolen, Slovakia
| | - František Máliš
- National Forest Centre - Forest Research Institute Zvolen, Zvolen, Slovakia
- Faculty of Forestry, Technical University Zvolen, Zvolen, Slovakia
| | - Petr Štěpánek
- Global Change Research Institute, Czech Academy of Sciences, Prague, Czech Republic
| | - Tomáš Hlásny
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Prague 6, Suchdol, Czech Republic
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10
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Hogan JA, Domke GM, Zhu K, Johnson DJ, Lichstein JW. Climate change determines the sign of productivity trends in US forests. Proc Natl Acad Sci U S A 2024; 121:e2311132121. [PMID: 38227667 PMCID: PMC10823222 DOI: 10.1073/pnas.2311132121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 12/01/2023] [Indexed: 01/18/2024] Open
Abstract
Forests are integral to the global land carbon sink, which has sequestered ~30% of anthropogenic carbon emissions over recent decades. The persistence of this sink depends on the balance of positive drivers that increase ecosystem carbon storage-e.g., CO2 fertilization-and negative drivers that decrease it-e.g., intensifying disturbances. The net response of forest productivity to these drivers is uncertain due to the challenge of separating their effects from background disturbance-regrowth dynamics. We fit non-linear models to US forest inventory data (113,806 plot remeasurements in non-plantation forests from ~1999 to 2020) to quantify productivity trends while accounting for stand age, tree mortality, and harvest. Productivity trends were generally positive in the eastern United States, where climate change has been mild, and negative in the western United States, where climate change has been more severe. Productivity declines in the western United States cannot be explained by increased mortality or harvest; these declines likely reflect adverse climate-change impacts on tree growth. In the eastern United States, where data were available to partition biomass change into age-dependent and age-independent components, forest maturation and increasing productivity (likely due, at least in part, to CO2 fertilization) contributed roughly equally to biomass carbon sinks. Thus, adverse effects of climate change appear to overwhelm any positive drivers in the water-limited forests of the western United States, whereas forest maturation and positive responses to age-independent drivers contribute to eastern US carbon sinks. The future land carbon balance of forests will likely depend on the geographic extent of drought and heat stress.
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Affiliation(s)
- J. Aaron Hogan
- Department of Biology, University of Florida, Gainesville, FL32611
| | - Grant M. Domke
- Northern Research Station, United States Department of Agriculture Forest Service, Saint Paul, MN55108
| | - Kai Zhu
- School for Environment and Sustainability, University of Michigan, Ann Arbor, MI48109
| | - Daniel J. Johnson
- School of Forest, Fisheries, and Geomatics Sciences, University of Florida, Gainesville, FL32611
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11
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Lozano-Calvo S, Loaiza JM, García JC, Tapias R, López F. Kinetic and hydrogen production analysis in the sequential valorization of a Populus clone by cold alkaline extraction and pyrolysis. Sci Rep 2024; 14:1509. [PMID: 38233531 PMCID: PMC10794177 DOI: 10.1038/s41598-024-52052-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 01/12/2024] [Indexed: 01/19/2024] Open
Abstract
This work employed a two-step biorefining process, consisting of a hemicellulose-rich liquor production through ultrasound-assisted cold alkaline extraction (CAE), followed by thermochemical treatment of the resultant solid phase. The post-CAE solid phase's pyrolytic potential was assessed by application of thermogravimetric analysis (TGA) and Friedman's isoconversional method, and also from hydrogen production. The solid phases remaining after the CAE treatment were more reactive than the untreated raw material. Notably, the alkali concentration employed in the first step was the individual variable most pronounced influence on their activation energy (Ea). Thus, at a degree of conversion α = 0.50, Ea ranged from 109.7 to 254.3 kJ/mol for the solid phases, compared to 177 kJ/mol for the raw material; this value decreased with rising glucan content. At maximal degradation, the post-CAE solid phases produced up to 15.57% v/v more hydrogen than did the untreated raw material.
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Affiliation(s)
- S Lozano-Calvo
- Research Centre for Technology of Products and Chemical Processes (PRO2TECS), Department of Chemical Engineering, University of Huelva, Av. 3 de Marzo S/N, 21071, Huelva, Spain.
| | - J M Loaiza
- Research Centre for Technology of Products and Chemical Processes (PRO2TECS), Department of Chemical Engineering, University of Huelva, Av. 3 de Marzo S/N, 21071, Huelva, Spain
| | - J C García
- Research Centre for Technology of Products and Chemical Processes (PRO2TECS), Department of Chemical Engineering, University of Huelva, Av. 3 de Marzo S/N, 21071, Huelva, Spain
| | - R Tapias
- Department of Forest Engineering, University of Huelva, Huelva, Spain
| | - F López
- Research Centre for Technology of Products and Chemical Processes (PRO2TECS), Department of Chemical Engineering, University of Huelva, Av. 3 de Marzo S/N, 21071, Huelva, Spain
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12
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Ryan KA, Lawrence GB. Recent, widespread nitrate decreases may be linked to persistent dissolved organic carbon increases in headwater streams recovering from past acidic deposition. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167646. [PMID: 37813265 DOI: 10.1016/j.scitotenv.2023.167646] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 09/14/2023] [Accepted: 10/05/2023] [Indexed: 10/11/2023]
Abstract
Long-term monitoring of water quality responses to natural and anthropogenic perturbation of watersheds informs policies for managing natural resources. Dissolved organic carbon (DOC) and nitrate (NO3-) in streams draining forested landscapes provide valuable information on ecosystem function due to their biogeochemical reactivity and solubility in water. Here we evaluate a 20-year record (2001-2021) of biweekly stream-water samples (n > 3000) and continuous discharge in three forested catchments in the Adirondack region of New York to investigate and interpret long-term trends in DOC and NO3- concentrations. Results from the intensively monitored catchments were compared with data from synoptic surveys of streams throughout the Adirondack region. A weighted regressions on time, discharge, and season (WRTDS) model, used to estimate daily flow-normalized concentrations, determined that DOC increased by ~30 to 50 % while NO3- decreased by ~50 to 70 % over the study period. The large amount of data from catchments with different soil properties permitted us to assess the relative effects of hydrology, season, and land cover factors on temporal trends in DOC and NO3- concentrations. We found weak evidence of climatic forcing of long-term increases in DOC, and instead contend that declining ionic strength in precipitation linked to declining anthropogenic acid deposition is driving DOC trends in stream waters. Nitrate concentrations were more variable but clearly decreased in recent years possibly related to declining N deposition. The recent increase in DOC:NO3- in all catchments indicates a major shift in stream stoichiometry that reflects changes in ecosystem functioning that may have important biogeochemical implications for terrestrial as well as aquatic ecosystems.
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Affiliation(s)
- Kevin A Ryan
- U.S. Geological Survey, New York Water Science Center, United States of America.
| | - Gregory B Lawrence
- U.S. Geological Survey, New York Water Science Center, United States of America
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13
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Muñoz E, Chanca I, Sierra CA. Increased atmospheric CO 2 and the transit time of carbon in terrestrial ecosystems. GLOBAL CHANGE BIOLOGY 2023; 29:6441-6452. [PMID: 37795922 DOI: 10.1111/gcb.16961] [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: 06/26/2023] [Revised: 09/12/2023] [Accepted: 09/12/2023] [Indexed: 10/06/2023]
Abstract
The response of terrestrial ecosystems to increased atmospheric CO2 concentrations is controversial and not yet fully understood, with previous large-scale forest manipulation experiments exhibiting contrasting responses. Although there is consensus that increased CO2 has a relevant effect on instantaneous processes such as photosynthesis and transpiration, there are large uncertainties regarding the fate of extra assimilated carbon in ecosystems. Filling this research gap is challenging because tracing the movement of new carbon across ecosystem compartments involves the study of multiple processes occurring over a wide range of timescales, from hours to millennia. We posit that a comprehensive quantification of the effect of increased CO2 must answer two interconnected questions: How much and for how long is newly assimilated carbon stored in ecosystems? Therefore, we propose that the transit time distribution of carbon is the key concept needed to effectively address these questions. Here, we show how the transit time distribution of carbon can be used to assess the fate of newly assimilated carbon and the timescales at which it is cycled in ecosystems. We use as an example a transit time distribution obtained from a tropical forest and show that most of the 60% of fixed carbon is respired in less than 1 year; therefore, we infer that under increased CO2 , most of the new carbon would follow a similar fate unless increased CO2 would cause changes in the rates at which carbon is cycled and transferred among ecosystem compartments. We call for a more frequent adoption of the transit time concept in studies seeking to quantify the ecosystem response to increased CO2 .
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Affiliation(s)
- Estefanía Muñoz
- Theoretical Ecosystem Ecology Group, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Ingrid Chanca
- Theoretical Ecosystem Ecology Group, Max Planck Institute for Biogeochemistry, Jena, Germany
- Laboratório de Radiocarbono, Instituto de Física, Universidade Federal Fluminense, Niterói, Brazil
| | - Carlos A Sierra
- Theoretical Ecosystem Ecology Group, Max Planck Institute for Biogeochemistry, Jena, Germany
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14
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Lloyd MK, Stein RA, Ibarra DE, Barclay RS, Wing SL, Stahle DW, Dawson TE, Stolper DA. Isotopic clumping in wood as a proxy for photorespiration in trees. Proc Natl Acad Sci U S A 2023; 120:e2306736120. [PMID: 37931112 PMCID: PMC10655223 DOI: 10.1073/pnas.2306736120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 09/22/2023] [Indexed: 11/08/2023] Open
Abstract
Photorespiration can limit gross primary productivity in terrestrial plants. The rate of photorespiration relative to carbon fixation increases with temperature and decreases with atmospheric [CO2]. However, the extent to which this rate varies in the environment is unclear. Here, we introduce a proxy for relative photorespiration rate based on the clumped isotopic composition of methoxyl groups (R-O-CH3) in wood. Most methoxyl C-H bonds are formed either during photorespiration or the Calvin cycle and thus their isotopic composition may be sensitive to the mixing ratio of these pathways. In water-replete growing conditions, we find that the abundance of the clumped isotopologue 13CH2D correlates with temperature (18-28 °C) and atmospheric [CO2] (280-1000 ppm), consistent with a common dependence on relative photorespiration rate. When applied to a global dataset of wood, we observe global trends of isotopic clumping with climate and water availability. Clumped isotopic compositions are similar across environments with temperatures below ~18 °C. Above ~18 °C, clumped isotopic compositions in water-limited and water-replete trees increasingly diverge. We propose that trees from hotter climates photorespire substantially more than trees from cooler climates. How increased photorespiration is managed depends on water availability: water-replete trees export more photorespiratory metabolites to lignin whereas water-limited trees either export fewer overall or direct more to other sinks that mitigate water stress. These disparate trends indicate contrasting responses of photorespiration rate (and thus gross primary productivity) to a future high-[CO2] world. This work enables reconstructing photorespiration rates in the geologic past using fossil wood.
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Affiliation(s)
- Max K. Lloyd
- Department of Earth and Planetary Science, University of California, Berkeley, CA94720
- Department of Geosciences, The Pennsylvania State University, University Park, PA16802
| | - Rebekah A. Stein
- Department of Earth and Planetary Science, University of California, Berkeley, CA94720
- Department of Chemistry and Physical Sciences, Quinnipiac University, Hamden, CT06518
| | - Daniel E. Ibarra
- Department of Earth and Planetary Science, University of California, Berkeley, CA94720
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, RI02912
| | - Richard S. Barclay
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC20560
| | - Scott L. Wing
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC20560
| | - David W. Stahle
- Department of Geosciences, University of Arkansas, Fayetteville, AR72701
| | - Todd E. Dawson
- Department of Integrative Biology, University of California, Berkeley, CA94720
| | - Daniel A. Stolper
- Department of Earth and Planetary Science, University of California, Berkeley, CA94720
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15
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Peng X, Jiang S, Liu S, Valbuena R, Smith A, Zhan Y, Shi Y, Ning Y, Feng S, Gao H, Wang Z. Long-term satellite observations show continuous increase of vegetation growth enhancement in urban environment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 898:165515. [PMID: 37451465 DOI: 10.1016/j.scitotenv.2023.165515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/18/2023]
Abstract
Urbanization shows continuous expansion and development, ushering in the co-evolution of urban environments and vegetation over time. Recent remote sensing-based studies have discovered prevalent vegetation growth enhancement in urban environments. However, whether there is a temporal evolution of the growth enhancement remains unknown and unexplored. Here we expanded the existing framework for assessing the long-term impact of urbanization on vegetation greenness (enhanced vegetation index, EVI) using long time series of remote sensing images and applied it in Changsha, the capital city of Hunan province in China. Results showed that vegetation growth experienced widespread enhancement from 2000 to 2017, and increased 1.8 times from 2000 to 2017, suggesting strong continuous adaptive capability of vegetation to urban conditions. Although the overall impact of urbanization was negative due to the replacement of vegetated surfaces, the growth enhancement nevertheless offset or compensated the direct loss of vegetated cover during urbanization in the magnitude of 28 % in 2000 to 44 % in 2017. Our study also revealed large spatial heterogeneity in vegetation growth response among various districts at different urbanization levels and found an emergent trend under the observed spatial heterogeneity toward an asymptotic maximum with urbanization, showing EVI converges to 0.22 in highly urbanized areas. We further found that the positive effect of urbanization on vegetation growth is a function of urbanization intensity and time, which implies that the effect of the urban environment on vegetation can be simulated and predicted, and can be verified in more cities in the future. Our study is the first to successfully quantify long-term spatial patterns on the co-evolution of urbanization and vegetation, providing a new understanding of the continuous adaptive responses of vegetation growth to urbanization and shedding light on predicting biological responses to future environmental change.
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Affiliation(s)
- Xi Peng
- College of Life Science and Technology, National Engineering Laboratory for Applied Technology in Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha 410004, China
| | - Shucheng Jiang
- College of Life Science and Technology, National Engineering Laboratory for Applied Technology in Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha 410004, China
| | - Shuguang Liu
- College of Life Science and Technology, National Engineering Laboratory for Applied Technology in Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha 410004, China.
| | - Rubén Valbuena
- School of Natural Sciences, Bangor University, Bangor, UK
| | - Andy Smith
- School of Natural Sciences, Bangor University, Bangor, UK
| | - Yang Zhan
- College of Life Science and Technology, National Engineering Laboratory for Applied Technology in Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha 410004, China
| | - Yi Shi
- College of Life Science and Technology, National Engineering Laboratory for Applied Technology in Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha 410004, China
| | - Ying Ning
- College of Life Science and Technology, National Engineering Laboratory for Applied Technology in Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha 410004, China
| | - Shuailong Feng
- College of Life Science and Technology, National Engineering Laboratory for Applied Technology in Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha 410004, China
| | - Haiqiang Gao
- College of Life Science and Technology, National Engineering Laboratory for Applied Technology in Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha 410004, China
| | - Zhao Wang
- College of Life Science and Technology, National Engineering Laboratory for Applied Technology in Forestry & Ecology in South China, Central South University of Forestry and Technology, Changsha 410004, China
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16
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Wu C, Qi G, Zhang J, Cheng J, Wang B. Porous Mo 3 P/Mo Nanorods as Efficient Mott-Schottky Cathode Catalysts for Low Polarization Li-CO 2 Battery. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2302078. [PMID: 37386784 DOI: 10.1002/smll.202302078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 05/22/2023] [Indexed: 07/01/2023]
Abstract
Li-CO2 battery with high energy density has aroused great interest recently, large-scale applications are hindered by the limited cathode catalysis performance and execrably cycle performance. Herein, Mo3 P/Mo Mott-Schottky heterojunction nanorod electrocatalyst with abundant porous structure is fabricated and served as cathodes for Li-CO2 batteries. The Mo3 P/Mo cathodes exhibit ultra-high discharge specific capacity of 10 577 mAh g-1 , low polarization voltage of 0.15 V, and high energy efficiency of up to 94.7%. Mott-Schottky heterojunction formed by Mo and Mo3 P drives electron transfer and optimizes the surface electronic structure, which is beneficial to accelerate the interface reaction kinetics. Distinctively, during the discharge process, the C2 O4 2- intermediates combine with Mo atoms to form a stable Mo-O coupling bridge on the catalyst surface, which effectively facilitate the formation and stabilization of Li2 C2 O4 products. In addition, the construction of the Mo-O coupling bridge between the Mott-Schottky heterojunction and Li2 C2 O4 promotes the reversible formation and decomposition of discharge products and optimizes the polarization performance of the Li-CO2 battery. This work provides another pathway for the development of heterostructure engineering electrocatalysts for high-performance Li-CO2 batteries.
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Affiliation(s)
- Chunhui Wu
- Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang, 621900, China
- Institute of Fundamental and Frontier Science, University of Electronic Science and Technology of China, Chengdu, 611731, China
- Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou, 313001, China
| | - Guicai Qi
- Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang, 621900, China
| | - Junxiang Zhang
- Institute of Fundamental and Frontier Science, University of Electronic Science and Technology of China, Chengdu, 611731, China
- Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou, 313001, China
| | - Jianli Cheng
- Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang, 621900, China
| | - Bin Wang
- Institute of Fundamental and Frontier Science, University of Electronic Science and Technology of China, Chengdu, 611731, China
- Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China, Huzhou, 313001, China
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17
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Zeng J, Zhou T, Xu Y, Lin Q, Tan E, Zhang Y, Wu X, Zhang J, Liu X. The fusion of multiple scale data indicates that the carbon sink function of the Qinghai-Tibet Plateau is substantial. CARBON BALANCE AND MANAGEMENT 2023; 18:19. [PMID: 37695559 PMCID: PMC10494389 DOI: 10.1186/s13021-023-00239-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 09/03/2023] [Indexed: 09/12/2023]
Abstract
BACKGROUND The Qinghai-Tibet Plateau is the "sensitive area" of climate change, and also the "driver" and "amplifier" of global change. The response and feedback of its carbon dynamics to climate change will significantly affect the content of greenhouse gases in the atmosphere. However, due to the unique geographical environment characteristics of the Qinghai-Tibet Plateau, there is still much controversy about its carbon source and sink estimation results. This study designed a new algorithm based on machine learning to improve the accuracy of carbon source and sink estimation by integrating multiple scale carbon input (net primary productivity, NPP) and output (soil heterotrophic respiration, Rh) information from remote sensing and ground observations. Then, we compared spatial patterns of NPP and Rh derived from the fusion of multiple scale data with other widely used products and tried to quantify the differences and uncertainties of carbon sink simulation at a regional scale. RESULTS Our results indicate that although global warming has potentially increased the Rh of the Qinghai-Tibet Plateau, it will also increase its NPP, and its current performance is a net carbon sink area (carbon sink amount is 22.3 Tg C/year). Comparative analysis with other data products shows that CASA, GLOPEM, and MODIS products based on remote sensing underestimate the carbon input of the Qinghai-Tibet Plateau (30-70%), which is the main reason for the severe underestimation of the carbon sink level of the Qinghai-Tibet Plateau (even considered as a carbon source). CONCLUSIONS The estimation of the carbon sink in the Qinghai-Tibet Plateau is of great significance for ensuring its ecological barrier function. It can deepen the community's understanding of the response to climate change in sensitive areas of the plateau. This study can provide an essential basis for assessing the uncertainty of carbon sources and sinks in the Qinghai-Tibet Plateau, and also provide a scientific reference for helping China achieve "carbon neutrality" by 2060.
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Affiliation(s)
- Jingyu Zeng
- Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education, Beijing Normal University, Beijing, 100875, China
- State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China
| | - Tao Zhou
- Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education, Beijing Normal University, Beijing, 100875, China.
- State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China.
| | - Yixin Xu
- Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education, Beijing Normal University, Beijing, 100875, China
- State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China
| | - Qiaoyu Lin
- Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education, Beijing Normal University, Beijing, 100875, China
- State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China
| | - E Tan
- Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education, Beijing Normal University, Beijing, 100875, China
- State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China
| | - Yajie Zhang
- Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education, Beijing Normal University, Beijing, 100875, China
- State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China
| | - Xuemei Wu
- Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education, Beijing Normal University, Beijing, 100875, China
- State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China
| | - Jingzhou Zhang
- Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education, Beijing Normal University, Beijing, 100875, China
- State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China
| | - Xia Liu
- Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of Education, Beijing Normal University, Beijing, 100875, China
- State Key Laboratory of Earth Surface Processes and Resource Ecology (ESPRE), Beijing Normal University, Beijing, 100875, China
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18
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Heo JB, Yun HR, Lee YS, Chung CH. Strategic biomodification for raw plant-based pretreatment biorefining toward sustainable chemistry. Crit Rev Biotechnol 2023; 43:870-883. [PMID: 35968908 DOI: 10.1080/07388551.2022.2092715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 03/16/2022] [Accepted: 05/08/2022] [Indexed: 11/03/2022]
Abstract
Plant-based pretreatment biorefining is the initial triggering process in biomass-conversion to bio-based chemical products. In view of chemical sustainability, the raw plant-based pretreatment biorefining process is more favorable than the fossil-based one. Its direct use contributes to reducing CO2 emissions and the production cost of the target products by eliminating costly steps, such as the separation and purification of intermediates. Three types of feedstock plant resources have been utilized as raw plant feedstock sources, such as: lignocellulosic, starchy, and inulin-rich feedstock plants. These plant sources can be directly used for bio-based chemical products. To enhance the efficiency of their pretreatment biorefining process, well-designed biomodification schemes are discussed in this review to afford important information on useful biomodification approaches. For lignocellulosic feedstock plants, the enzymes and regulatory elements involved in lignin reduction are discussed using: COMT, GAUT4, CSE, PvMYB4 repressor, etc. For inulin-rich feedstock plants, 1-SST, 1-FFT, 1-FEH, and endoinulinase are illustrated in relation with the reduction of chain length of inulin polymer. For starchy feedstock plants, their biomodification is targeted to enhancing the depolymerization efficiency of starch to glucose monomer units. For this biomodification target, six candidates are discussed. These are SBE I, SBE IIa, SBE IIb, GBSS I, PTSTI, GWD 1, and PTSTI. The biomodification strategies discussed here promise to be conducive to enhancing the efficiency of the plant-based pretreatment biorefining process.
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Affiliation(s)
- Jae Bok Heo
- Department of Molecular Genetic Biotechnology, Dong-A University, Busan, South Korea
| | - Hee Rang Yun
- Department of Molecular Genetic Biotechnology, Dong-A University, Busan, South Korea
| | - Yong-Suk Lee
- Research Institute for Basic Sciences, Pukyong National University, Busan, South Korea
| | - Chung-Han Chung
- Department of Biotechnology, Dong-A University, Busan, South Korea
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19
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Ge Y, Li L, Xi S, Ma L, Luan Z, Zhang X. Raman spectral characteristics of 12CO 2/ 13CO 2 and quantitative measurements of carbon isotopic compositions from 50 to 450 °C and 50 to 400 bar. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 296:122651. [PMID: 37060650 DOI: 10.1016/j.saa.2023.122651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/27/2023] [Accepted: 03/17/2023] [Indexed: 06/19/2023]
Abstract
The carbon isotopic composition of CO2 is traced to its different origins and widely used in the fields of geology, biology, and chemistry. Raman spectroscopy can be performed in situ, is nondestructive, and requires no sample preparation; these characteristics enable Raman spectroscopy to be considered a new alternative method to measure the carbon isotopic composition of CO2. In this work, Raman spectra of high-purity 13CO2, 12CO2, and six 12CO2-13CO2 binary mixtures with known mixing ratios were collected using a High Pressure Optical Cell (HPOC) at 50-450 °C and 50-400 bar. The results showed that the characteristic peak positions of both 13CO2 and 12CO2 shift to lower wavenumbers with increasing temperature and decreasing pressure, but the peak positions of 13CO2 show a larger shift. The peak position difference of the corresponding characteristic peaks between 13CO2 and 12CO2 is greater than 15 cm-1 under the above temperatures and pressures, and the peaks can be distinguished. However, ν-13 overlays νH.B.12 near 1265 cm-1, ν+12 overlaps νH.B.13 near 1288 cm-1. The existence of 13CO2 can cause a change in the Fermi diad splitting of 12CO2 and affect the establishment of CO2 Raman densimeters. The positive correlation obtained between the peak intensity ratio and the content ratio is affected by temperature, pressure, and 13CO2 content. I+13/I+12 and I-13/I-12 were selected as the quantitative indices to establish Raman quantitative analysis models for the determination of the carbon isotopic composition of CO2, which can be applied to in-situ measurements of high-temperature and high-pressure systems.
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Affiliation(s)
- Yuzhou Ge
- CAS Key Laboratory of Marine Geology and Environment & Center of Deep Sea Research, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Geology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266061, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lianfu Li
- CAS Key Laboratory of Marine Geology and Environment & Center of Deep Sea Research, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shichuan Xi
- CAS Key Laboratory of Marine Geology and Environment & Center of Deep Sea Research, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Liang Ma
- CAS Key Laboratory of Marine Geology and Environment & Center of Deep Sea Research, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhendong Luan
- CAS Key Laboratory of Marine Geology and Environment & Center of Deep Sea Research, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Geology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266061, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xin Zhang
- CAS Key Laboratory of Marine Geology and Environment & Center of Deep Sea Research, Institute of Oceanology, Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Geology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266061, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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20
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Jung CG, Keyser AR, Remy CC, Krofcheck D, Allen CD, Hurteau MD. Topographic information improves simulated patterns of post-fire conifer regeneration in the southwest United States. GLOBAL CHANGE BIOLOGY 2023; 29:4342-4353. [PMID: 37211629 DOI: 10.1111/gcb.16764] [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: 01/15/2023] [Revised: 04/19/2023] [Accepted: 05/07/2023] [Indexed: 05/23/2023]
Abstract
The western United States is projected to experience more frequent and severe wildfires in the future due to drier and hotter climate conditions, exacerbating destructive wildfire impacts on forest ecosystems such as tree mortality and unsuccessful post-fire regeneration. While empirical studies have revealed strong relationships between topographical information and plant regeneration, ecological processes in ecosystem models have either not fully addressed topography-mediated effects on the probability of plant regeneration, or the probability is only controlled by climate-related factors, for example, water and light stresses. In this study, we incorporated seedling survival data based on a planting experiment in the footprint of the 2011 Las Conchas Fire into the Photosynthesis and EvapoTranspiration (PnET) extension of the LANDIS-II model by adding topographic and an additional climatic variable to the probability of regeneration. The modified algorithm included topographic parameters such as heat load index and ground slope and spring precipitation. We ran simulations on the Las Conchas Fire landscape for 2012-2099 using observed and projected climate data (i.e., Representative Concentration Pathway 4.5 and 8.5). Our modification significantly reduced the number of regeneration events of three common southwestern conifer tree species (piñon, ponderosa pine, and Douglas-fir), leading to decreases in aboveground biomass, regardless of climate scenario. The modified algorithm decreased regeneration at higher elevations and increased regeneration at lower elevations relative to the original algorithm. Regenerations of three species also decreased in eastern aspects. Our findings suggest that ecosystem models may overestimate post-fire regeneration events in the southwest United States. To better represent regeneration processes following wildfire, ecosystem models need refinement to better account for the range of factors that influence tree seedling establishment. This will improve model utility for projecting the combined effects of climate and wildfire on tree species distributions.
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Affiliation(s)
- Chang Gyo Jung
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Alisa R Keyser
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
- Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, Colorado, USA
| | - Cecile C Remy
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
- Institute of Geography, Augsburg University, Augsburg, Germany
| | - Daniel Krofcheck
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Craig D Allen
- Department of Geography and Environmental Studies, University of New Mexico, Albuquerque, New Mexico, USA
| | - Matthew D Hurteau
- Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
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21
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He Y, Liu Y, Lei L, Terrer C, Huntingford C, Peñuelas J, Xu H, Piao S. CO 2 fertilization contributed more than half of the observed forest biomass increase in northern extra-tropical land. GLOBAL CHANGE BIOLOGY 2023; 29:4313-4326. [PMID: 37277951 DOI: 10.1111/gcb.16806] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 04/23/2023] [Accepted: 05/11/2023] [Indexed: 06/07/2023]
Abstract
The existence of a large-biomass carbon (C) sink in Northern Hemisphere extra-tropical ecosystems (NHee) is well-established, but the relative contribution of different potential drivers remains highly uncertain. Here we isolated the historical role of carbon dioxide (CO2 ) fertilization by integrating estimates from 24 CO2 -enrichment experiments, an ensemble of 10 dynamic global vegetation models (DGVMs) and two observation-based biomass datasets. Application of the emergent constraint technique revealed that DGVMs underestimated the historical response of plant biomass to increasing [CO2 ] in forests (β Forest Mod ) but overestimated the response in grasslands (β Grass Mod ) since the 1850s. Combining the constrainedβ Forest Mod (0.86 ± 0.28 kg C m-2 [100 ppm]-1 ) with observed forest biomass changes derived from inventories and satellites, we identified that CO2 fertilization alone accounted for more than half (54 ± 18% and 64 ± 21%, respectively) of the increase in biomass C storage since the 1990s. Our results indicate that CO2 fertilization dominated the forest biomass C sink over the past decades, and provide an essential step toward better understanding the key role of forests in land-based policies for mitigating climate change.
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Affiliation(s)
- Yue He
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Yongwen Liu
- State Key Laboratory of Earth System and Environmental Resources of the Tibetan Plateau (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
| | - Lingjie Lei
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - César Terrer
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | | | - Josep Peñuelas
- CREAF, Cerdanyola del Valles, Barcelona, Spain
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, Barcelona, Spain
| | - Hao Xu
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
| | - Shilong Piao
- Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing, China
- State Key Laboratory of Earth System and Environmental Resources of the Tibetan Plateau (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
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22
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Hong Y, Liu X, Camarero JJ, Xu G, Zhang L, Zeng X, Aritsara ANA, Zhang Y, Wang W, Xing X, Lu Q. The effects of intrinsic water-use efficiency and climate on wood anatomy. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2023:10.1007/s00484-023-02475-7. [PMID: 37072578 DOI: 10.1007/s00484-023-02475-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 04/05/2023] [Accepted: 04/11/2023] [Indexed: 05/03/2023]
Abstract
Climate warming may induce growth decline in warm-temperate areas subjected to seasonal soil moisture deficit, whereas increasing atmospheric CO2 concentration (Ca) is expected to enhance tree growth. An accurate understanding of tree growth and physiological processes responding to climate warming and increasing Ca is critical. Here, we analyzed tree-ring stable carbon isotope and wood anatomical traits of Pinus tabuliformis from Qinling Mountains in China to understand how lumen diameter (LD) determining potential hydraulic conductivity and cell-wall thickness (CWT) determining carbon storage responded to climate and Ca. The effects of climate and Ca on intrinsic water-use efficiency (iWUE) were isolated, and iWUE values due to only-climate (iWUEClim) and only-CO2 effects (iWUECO2) were obtained. During a low-iWUE period, the influences of climate on earlywood (EW) LD and latewood (LW) CWT prevailed. During a high-iWUE period, CO2 fertilization promoted cell enlargement and carbon storage but this was counteracted by a negative influence of climate warming. The limiting direct effects of iWUEClim and indirect effects of climate on EW LD were greater than on LW CWT. P. tabuliformis in temperate forests will face a decline of growth and carbon fixation, but will produce embolism-resistant tracheids with narrow lumen responding to future hotter droughts.
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Affiliation(s)
- Yixue Hong
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, China
- State Key Laboratory of Biocontrol, School of Ecology, Shenzhen Campus of Sun Yat-Sen University, Shenzhen, 518107, China
| | - Xiaohong Liu
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, China.
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
| | - J Julio Camarero
- Instituto Pirenaico de Ecología (IPE-CSIC), Zaragoza, 50092, Spain
| | - Guobao Xu
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Lingnan Zhang
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, China
| | - Xiaomin Zeng
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, China
| | - Amy Ny Aina Aritsara
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangxi University, Nanning, 530004, China
| | - Yu Zhang
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, China
| | - Wenzhi Wang
- The Key Laboratory of Mountain Environment Evolution and Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China
| | - Xiaoyu Xing
- Qinling National Botanical Garden, Xi'an, 710061, China
| | - Qiangqiang Lu
- School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, China
- Xi'an Botanical Garden of Shaanxi Province (Institute of Botany of Shaanxi Province), Xi'an, 710061, China
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23
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Hemes KS, Norlen CA, Wang JA, Goulden ML, Field CB. The magnitude and pace of photosynthetic recovery after wildfire in California ecosystems. Proc Natl Acad Sci U S A 2023; 120:e2201954120. [PMID: 37011220 PMCID: PMC10104501 DOI: 10.1073/pnas.2201954120] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 01/26/2023] [Indexed: 04/05/2023] Open
Abstract
Wildfire modifies the short- and long-term exchange of carbon between terrestrial ecosystems and the atmosphere, with impacts on ecosystem services such as carbon uptake. Dry western US forests historically experienced low-intensity, frequent fires, with patches across the landscape occupying different points in the fire-recovery trajectory. Contemporary perturbations, such as recent severe fires in California, could shift the historic stand-age distribution and impact the legacy of carbon uptake on the landscape. Here, we combine flux measurements of gross primary production (GPP) and chronosequence analysis using satellite remote sensing to investigate how the last century of fires in California impacted the dynamics of ecosystem carbon uptake on the fire-affected landscape. A GPP recovery trajectory curve of more than five thousand fires in forest ecosystems since 1919 indicated that fire reduced GPP by [Formula: see text] g C m[Formula: see text] y[Formula: see text]([Formula: see text]) in the first year after fire, with average recovery to prefire conditions after [Formula: see text] y. The largest fires in forested ecosystems reduced GPP by [Formula: see text] g C m[Formula: see text] y[Formula: see text] (n = 401) and took more than two decades to recover. Recent increases in fire severity and recovery time have led to nearly [Formula: see text] MMT CO[Formula: see text] (3-y rolling mean) in cumulative forgone carbon uptake due to the legacy of fires on the landscape, complicating the challenge of maintaining California's natural and working lands as a net carbon sink. Understanding these changes is paramount to weighing the costs and benefits associated with fuels management and ecosystem management for climate change mitigation.
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Affiliation(s)
- Kyle S. Hemes
- Woods Institute for the Environment, Stanford University, Stanford, CA92697
| | - Carl A. Norlen
- Department of Earth System Science, University of California, Irvine, CA92697
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA94305
| | - Jonathan A. Wang
- Department of Earth System Science, University of California, Irvine, CA92697
| | - Michael L. Goulden
- Department of Earth System Science, University of California, Irvine, CA92697
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Yong Z, Wang Z, Xiong J, Tian J. Tropical volcanic eruptions reduce vegetation net carbon uptake on the Qinghai-Tibet Plateau under background climate conditions. FRONTIERS IN PLANT SCIENCE 2023; 14:1122959. [PMID: 37008501 PMCID: PMC10061027 DOI: 10.3389/fpls.2023.1122959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 02/28/2023] [Indexed: 06/19/2023]
Abstract
The vegetation carbon uptake plays an important role in the terrestrial carbon cycle on the Qinghai-Tibet Plateau (QTP), while it is extremely sensitive to the impact of natural external forcings. Until now, there is limited knowledge on the spatial-temporal patterns of vegetation net carbon uptake (VNCU) after the force that caused by tropical volcanic eruptions. Here, we conducted an exhaustive reconstruction of VNCU on the QTP over the last millennium, and used a superposed epoch analysis to characterize the VNCU response of the QTP after the tropical volcanic eruptions. We then further investigated the divergent changes of VNCU response across different elevation gradients and vegetation types, and the impact of teleconnection forcing on VNCU after volcanic eruptions. Within a climatic background, we found that VNCU of the QTP tends to decrease after large volcanic eruptions, lasting until about 3 years, with a maximum decrease value occurring in the following 1 year. The spatial and temporal patterns of the VNCU were mainly driven by the post-eruption climate and moderated by the negative phase trends of El Niño-Southern Oscillation and the Atlantic multidecadal oscillation. In addition, elevation and vegetation types were undeniable driving forces associated with VNCU on QTP. Different water-heat conditions and vegetation types contributed to significant differences in the response and recovery processes of VNCU. Our results emphasized the response and recovery processes of VNCU to volcanic eruptions without the strong anthropogenic forcings, while the influence mechanisms of natural forcing on VNCU should receive more attention.
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Affiliation(s)
- Zhiwei Yong
- School of Geoscience and Technology, Southwest Petroleum University, Chengdu, China
| | - Zegen Wang
- School of Geoscience and Technology, Southwest Petroleum University, Chengdu, China
| | - Junnan Xiong
- School of Civil Engineering and Geomatics, Southwest Petroleum University, Chengdu, China
- Institute of Oil and Gas Spatial Information Engineering, Southwest Petroleum University, Chengdu, China
| | - Jie Tian
- School of Civil Engineering and Geomatics, Southwest Petroleum University, Chengdu, China
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25
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Xu X, Liu J, Jiao F, Zhang K, Ye X, Gong H, Lin N, Zou C. Ecological engineering induced carbon sinks shifting from decreasing to increasing during 1981-2019 in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 864:161037. [PMID: 36565873 DOI: 10.1016/j.scitotenv.2022.161037] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 06/17/2023]
Abstract
Substantial evidence shows that most of China's terrestrial ecosystems are important carbon sinks. However, the nonlinear trend of the carbon sinks and their nonlinear response to driving factors are unclear. Taking the net ecosystem productivity (NEP) as a proxy for the ecosystem carbon sink, the nonlinear relationships between the monotonically increasing trends and decreasing to increasing shifts in the carbon sink to climate change and ecological engineering were investigated based on ensemble empirical mode decomposition (EEMD) and machine learning algorithm (boosted regression tree model, BRT). The results suggest that 16.75 % of the carbon sinks in China experienced a monotonic increase. Additionally, 20.55 % of the carbon sinks shifted from decreasing to increasing trends, primarily after 1995, and these carbon sinks were located in the key ecological engineering areas, such as the middle reaches of the Yellow River shelterbelt program area, the Liaohe shelterbelt program area, the Grain to Green program area, and the Three-North Forest shelterbelt program area. Moreover, carbon sinks exhibited strong spatial autocorrelation with low-low clustering in the north and high-high clustering in the south. The increase in CO2 (slope of CO2 < 1.8 g/m2/s/y) and solar radiation (slope of radiation >1 w/m2/y) promoted the monotonic increase in the carbon sinks in the center of China. The increase in the areas of forest and grassland shifted the carbon sink trend from decreasing to increasing in the key ecological engineering program areas, and economic development reversed the carbon sink reduction in the Pearl River shelterbelt program area. These findings highlight the positive effect of ecological engineering on carbon sinks and provide adaptation strategies and guidance for China to achieve the "carbon neutrality" target.
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Affiliation(s)
- Xiaojuan Xu
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China
| | - Jing Liu
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China
| | - Fusheng Jiao
- School of Geography, Nanjing Normal University, Nanjing 210023, China
| | - Kun Zhang
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China
| | - Xin Ye
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China
| | - Haibo Gong
- School of Geography, Nanjing Normal University, Nanjing 210023, China
| | - Naifeng Lin
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China.
| | - Changxin Zou
- Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China.
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26
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Lu X, Chen Y, Sun Y, Xu Y, Xin Y, Mo Y. Spatial and temporal variations of net ecosystem productivity in Xinjiang Autonomous Region, China based on remote sensing. FRONTIERS IN PLANT SCIENCE 2023; 14:1146388. [PMID: 36866372 PMCID: PMC9973376 DOI: 10.3389/fpls.2023.1146388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Net ecosystem productivity (NEP), which plays a key role in the carbon cycle, is an important indicator of the ecosystem's carbon budget. In this paper, the spatial and temporal variations of NEP over Xinjiang Autonomous Region, China from 2001 to 2020 were studied based on remote sensing and climate re-analysis data. The modified Carnegie Ames Stanford Approach (CASA) model was employed to estimate net primary productivity (NPP), and the soil heterotrophic respiration model was used to calculate soil heterotrophic respiration. Then NEP was obtained by calculating the difference between NPP and heterotrophic respiration. The annual mean NEP of the study area was high in the east and low in the west, high in the north and low in the south. The 20-year mean vegetation NEP of the study area is 128.54 gC·m-2, indicating that the study area is a carbon sink on the whole. From 2001 to 2020, the annual mean vegetation NEP ranged between 93.12 and 158.05 gC·m-2, and exhibited an increasing trend in general. 71.46% of the vegetation area showed increasing trends of NEP. NEP exhibited a positive relationship with precipitation and a negative relationship with air temperature, and the correlation with air temperature was more significant. The work reveals the spatio-temporal dynamics of NEP in Xinjiang Autonomous Region and can provide a valuable reference for assessing regional carbon sequestration capacity.
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Affiliation(s)
- Xiangjun Lu
- The First Ecological and Environment Monitoring Station of Xinjiang Production and Construction Corps, Urumchi, China
| | - Yang Chen
- School of Remote Sensing and Geomatics Engineering, Nanjing University of Information Science & Technology, Nanjing, China
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Yuyin Sun
- The First Ecological and Environment Monitoring Station of Xinjiang Production and Construction Corps, Urumchi, China
| | - Yongming Xu
- School of Remote Sensing and Geomatics Engineering, Nanjing University of Information Science & Technology, Nanjing, China
| | - Yan Xin
- School of Remote Sensing and Geomatics Engineering, Nanjing University of Information Science & Technology, Nanjing, China
| | - Yaping Mo
- School of Remote Sensing and Geomatics Engineering, Nanjing University of Information Science & Technology, Nanjing, China
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27
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Gojon A, Cassan O, Bach L, Lejay L, Martin A. The decline of plant mineral nutrition under rising CO 2: physiological and molecular aspects of a bad deal. TRENDS IN PLANT SCIENCE 2023; 28:185-198. [PMID: 36336557 DOI: 10.1016/j.tplants.2022.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 09/13/2022] [Accepted: 09/28/2022] [Indexed: 05/26/2023]
Abstract
The elevation of atmospheric CO2 concentration has a strong impact on the physiology of C3 plants, far beyond photosynthesis and C metabolism. In particular, it reduces the concentrations of most mineral nutrients in plant tissues, posing major threats on crop quality, nutrient cycles, and carbon sinks in terrestrial agro-ecosystems. The causes of the detrimental effect of high CO2 levels on plant mineral status are not understood. We provide an update on the main hypotheses and review the increasing evidence that, for nitrogen, this detrimental effect is associated with direct inhibition of key mechanisms of nitrogen uptake and assimilation. We also mention promising strategies for identifying genotypes that will maintain robust nutrient status in a future high-CO2 world.
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Affiliation(s)
- Alain Gojon
- Institut des Sciences des Plantes de Montpellier (IPSiM), Université de Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Institut Agro, Montpellier, France
| | - Océane Cassan
- Institut des Sciences des Plantes de Montpellier (IPSiM), Université de Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Institut Agro, Montpellier, France
| | - Liên Bach
- Institut des Sciences des Plantes de Montpellier (IPSiM), Université de Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Institut Agro, Montpellier, France
| | - Laurence Lejay
- Institut des Sciences des Plantes de Montpellier (IPSiM), Université de Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Institut Agro, Montpellier, France
| | - Antoine Martin
- Institut des Sciences des Plantes de Montpellier (IPSiM), Université de Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Institut Agro, Montpellier, France.
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28
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Labrière N, Davies SJ, Disney MI, Duncanson LI, Herold M, Lewis SL, Phillips OL, Quegan S, Saatchi SS, Schepaschenko DG, Scipal K, Sist P, Chave J. Toward a forest biomass reference measurement system for remote sensing applications. GLOBAL CHANGE BIOLOGY 2023; 29:827-840. [PMID: 36270799 PMCID: PMC10099565 DOI: 10.1111/gcb.16497] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 10/14/2022] [Indexed: 05/02/2023]
Abstract
Forests contribute to climate change mitigation through carbon storage and uptake, but the extent to which this carbon pool varies in space and time is still poorly known. Several Earth Observation missions have been specifically designed to address this issue, for example, NASA's GEDI, NASA-ISRO's NISAR and ESA's BIOMASS. Yet, all these missions' products require independent and consistent validation. A permanent, global, in situ, site-based forest biomass reference measurement system relying on ground data of the highest possible quality is therefore needed. Here, we have assembled a list of almost 200 high-quality sites through an in-depth review of the literature and expert knowledge. In this study, we explore how representative these sites are in terms of their coverage of environmental conditions, geographical space and biomass-related forest structure, compared to those experienced by forests worldwide. This work also aims at identifying which sites are the most representative, and where to invest to improve the representativeness of the proposed system. We show that the environmental coverage of the system does not seem to improve after at least the 175 most representative sites are included, but geographical and structural coverages continue to improve as more sites are added. We highlight the areas of poor environmental, geographical, or structural coverage, including, but not limited to, Canada, the western half of the USA, Mexico, Patagonia, Angola, Zambia, eastern Russia, and tropical and subtropical highlands (e.g. in Colombia, the Himalayas, Borneo, Papua). For the proposed system to succeed, we stress that (1) data must be collected and processed applying the same standards across all countries and continents; (2) system establishment and management must be inclusive and equitable, with careful consideration of working conditions; and (3) training and site partner involvement in downstream activities should be mandatory.
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Affiliation(s)
- Nicolas Labrière
- Evolution and Biological Diversity (EDB)CNRS/IRD/UPSToulouseFrance
| | - Stuart J. Davies
- Forest Global Earth ObservatorySmithsonian Tropical Research InstituteWashingtonDistrict of ColumbiaUSA
| | - Mathias I. Disney
- Department of GeographyUniversity College London (UCL)LondonUK
- NERC National Centre for Earth Observation (NCEO)LondonUK
| | - Laura I. Duncanson
- Department of Geographical SciencesUniversity of MarylandCollege ParkMarylandUSA
| | - Martin Herold
- GFZ German Research Centre for GeosciencesPotsdamBrandenburgGermany
| | - Simon L. Lewis
- Department of GeographyUniversity College London (UCL)LondonUK
- School of GeographyUniversity of LeedsLeedsUK
| | | | - Shaun Quegan
- School of Mathematics and StatisticsUniversity of SheffieldSheffieldUK
| | - Sassan S. Saatchi
- Jet Propulsion Laboratory (JPL)California Institute of TechnologyPasadenaCaliforniaUSA
| | - Dmitry G. Schepaschenko
- International Institute for Applied Systems Analysis (IIASA)LaxenburgAustria
- Center for Forest Ecology and Productivity of the Russian Academy of SciencesMoscowRussia
| | | | | | - Jérôme Chave
- Evolution and Biological Diversity (EDB)CNRS/IRD/UPSToulouseFrance
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29
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Acclimation of phenology relieves leaf longevity constraints in deciduous forests. Nat Ecol Evol 2023; 7:198-204. [PMID: 36635342 DOI: 10.1038/s41559-022-01946-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 11/02/2022] [Indexed: 01/13/2023]
Abstract
Leaf phenology is key for regulating total growing-season mass and energy fluxes. Long-term temporal trends towards earlier leaf unfolding are observed across Northern Hemisphere forests. Phenological dates also vary between years, whereby end-of-season (EOS) dates correlate positively with start-of-season (SOS) dates and negatively with growing-season total net CO2 assimilation (Anet). These associations have been interpreted as the effect of a constrained leaf longevity or of premature carbon (C) sink saturation-with far-reaching consequences for long-term phenology projections under climate change and rising CO2. Here, we use multidecadal ground and remote-sensing observations to show that the relationships between Anet and EOS are opposite at the interannual and the decadal time scales. A decadal trend towards later EOS persists in parallel with a trend towards increasing Anet-in spite of the negative Anet-EOS relationship at the interannual scale. This finding is robust against the use of diverse observations and models. Results indicate that acclimation of phenology has enabled plants to transcend a constrained leaf longevity or premature C sink saturation over the course of several decades, leading to a more effective use of available light and a sustained extension of the vegetation CO2 uptake season over time.
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Lian X, Jiao L, Liu Z. Saturation response of enhanced vegetation productivity attributes to intricate interactions. GLOBAL CHANGE BIOLOGY 2023; 29:1080-1095. [PMID: 36367336 DOI: 10.1111/gcb.16522] [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: 08/10/2022] [Revised: 10/24/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
Evidence for the multifaceted responses of terrestrial ecosystems has been shown by the weakening of CO2 fertilization-induced and warming-controlled productivity gains. The intricate relationship between vegetation productivity and various environmental controls still remains elusive spatially. Here several inherent preponderances make China a natural experimental setting to investigate the interaction and relative contributions of five drivers to gross primary productivity for the period from 1982 to 2018 (i.e., elevated atmospheric CO2 concentrations, climate change, nutrient availability, anthropogenic land use change, and soil moisture) by coupling multiple long-term datasets. Despite a strikingly prominent enhancement of vegetation productivity in China, it exhibits similar saturation responses to the aforementioned environmental drivers (elevated CO2 , climatic factors, and soil moisture). The CO2 fertilization-dominated network explains the long-term variations in vegetation productivity in humid regions, but its effect is clearly attenuated or even absent in arid and alpine environments controlled by climate and soil moisture. Divergence in interactions also provides distinct evidence that water availability plays an essential role in limiting the potential effects of climate change and elevated CO2 concentrations on vegetation productivity. Unprecedented industrialization and dramatic surface changes may have breached critical thresholds of terrestrial ecosystems under the diverse natural environment and thus forced a shift from a period dominated by CO2 fertilization to a period with nonlinear interactions. These findings suggest that future benefits in terrestrial ecosystems are likely to be counteracted by uncertainties in the complicated network, implying an increasing reliance on human societies to combat potential risks. Our results therefore highlight the need to account for the intricate interactions globally and thus incorporate them into mitigation and adaptation policies.
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Affiliation(s)
- Xihong Lian
- School of Resource and Environmental Sciences, Wuhan University, Wuhan, China
- Key Laboratory of Geographic Information System, Ministry of Education, Wuhan University, Wuhan, China
| | - Limin Jiao
- School of Resource and Environmental Sciences, Wuhan University, Wuhan, China
- Key Laboratory of Geographic Information System, Ministry of Education, Wuhan University, Wuhan, China
| | - Zejin Liu
- School of Resource and Environmental Sciences, Wuhan University, Wuhan, China
- Key Laboratory of Geographic Information System, Ministry of Education, Wuhan University, Wuhan, China
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Soil-vegetation moisture capacitor maintains dry season vegetation productivity over India. Sci Rep 2023; 13:888. [PMID: 36650187 PMCID: PMC9845320 DOI: 10.1038/s41598-022-27277-6] [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: 10/04/2022] [Accepted: 12/29/2022] [Indexed: 01/19/2023] Open
Abstract
India receives more than 70% of its annual rainfall in the summer monsoon from June to September. The rainfall is scanty and scattered for the rest of the year. Combining satellite data and model simulations, we show that the soil-vegetation continuum works as a natural capacitor of water, storing the monsoon pulse and releasing the moisture to the atmosphere through evapotranspiration over approximately 135 days when the moisture supply from precipitation is less than the evapotranspiration losses. The total Gross Primary Productivity of vegetation in India during the capacitor period accounts for almost 35% of the total annual GPP value. It primarily depends on the soil moisture at the beginning of the period, a measure of moisture capacitance of soil, with a correlation of 0.6. Given that India is the second largest contributor to recent global greening, its soil-vegetation water capacitance plays a significant role in the global carbon balance.
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Warming-induced tree growth may help offset increasing disturbance across the Canadian boreal forest. Proc Natl Acad Sci U S A 2023; 120:e2212780120. [PMID: 36595673 PMCID: PMC9926259 DOI: 10.1073/pnas.2212780120] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Large projected increases in forest disturbance pose a major threat to future wood fiber supply and carbon sequestration in the cold-limited, Canadian boreal forest ecosystem. Given the large sensitivity of tree growth to temperature, warming-induced increases in forest productivity have the potential to reduce these threats, but research efforts to date have yielded contradictory results attributed to limited data availability, methodological biases, and regional variability in forest dynamics. Here, we apply a machine learning algorithm to an unprecedented network of over 1 million tree growth records (1958 to 2018) from 20,089 permanent sample plots distributed across both Canada and the United States, spanning a 16.5 °C climatic gradient. Fitted models were then used to project the near-term (2050 s time period) growth of the six most abundant tree species in the Canadian boreal forest. Our results reveal a large, positive effect of increasing thermal energy on tree growth for most of the target species, leading to 20.5 to 22.7% projected gains in growth with climate change under RCP 4.5 and 8.5. The magnitude of these gains, which peak in the colder and wetter regions of the boreal forest, suggests that warming-induced growth increases should no longer be considered marginal but may in fact significantly offset some of the negative impacts of projected increases in drought and wildfire on wood supply and carbon sequestration and have major implications on ecological forecasts and the global economy.
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Li W, Tan L, Peng M, Chen H, Tan C, Zhao E, Zhang L, Peng H, Liang Y. The spatial distribution of phytoliths and phytolith-occluded carbon in wheat (Triticum aestivum L.) ecosystem in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 850:158005. [PMID: 35964741 DOI: 10.1016/j.scitotenv.2022.158005] [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: 06/25/2022] [Revised: 08/07/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
Phytolith is a form of SiO2 in plants. Carbon can be sequestrated as phytolith-occluded carbon (PhytOC) during the formation of phytoliths. PhytOC is characterized by its high resistance to temperature, oxidation and decomposition under protection of phytoliths and can be stored in the soil for thousands of years. Soil also is a huge PhytOC sink; however, most studies focus on PhytOC storage in straw and other residues. Wheat is a major staple food crop accumulating high content of Si and distributed widely, while its potential for PhytOC is not clear. At present, PhytOC storage only considers on the average value, but not on the relationship between ecological factors and the spatial distribution of PhytOC sequestration. Climatic factors and soil physiochemical properties together affect the formation process and stability of phytoliths. In our study, we collected wheat straw and soil samples from 95 sites among five provinces to extract phytolith and PhytOC. We constructed XGBoost model to predict the spatial distribution of phytolith and PhytOC across the country using the national soil testing and formula fertilization nutrient dataset and climate data. As a result, soil physiochemical factors such as available silicon (Siavail), total carbon (Ctot) and total nitrogen (Ntot) and climate factors related to temperature and precipitation have a great positive impact on the production of phytoliths and PhytOC. Meanwhile, PhytOC storage in wheat ecosystems was estimated to be 7.59 × 106 t, which is equivalent to 27.83 Tg of CO2. In China, the distribution characteristics of phytoliths and PhytOC in wheat straw and soil display a trend of decrease from south to north. He'nan Province is the largest wheat production area, producing approximately 1.59 × 106 t PhytOC per year. Therefore, PhytOC is a stable CO2 sink pathway in the agricultural ecosystems, which is of great importance for mitigating climate warming.
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Affiliation(s)
- Wenjuan Li
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Li Tan
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Miao Peng
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hao Chen
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Che Tan
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Enqiang Zhao
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Lei Zhang
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hongyun Peng
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yongchao Liang
- Ministry of Education Key Laboratory of Environment Remediation and Ecological Health, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China.
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Santos GADA, Morais Filho LFF, Meneses KCD, Silva Junior CAD, Rolim GDS, La Scala N. Hot spots and anomalies of CO2 over eastern Amazonia, Brazil: A time series from 2015 to 2018. ENVIRONMENTAL RESEARCH 2022; 215:114379. [PMID: 36162477 DOI: 10.1016/j.envres.2022.114379] [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: 07/18/2022] [Revised: 09/13/2022] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
The easternmost Amazon, located in the Maranhão State, in Brazil, has suffered massive deforestation in recent years, which has devastated almost 80% of the original vegetation. We aim to characterize hot spots, hot moments, atmospheric carbon dioxide anomalies (Xco2, ppm), and their interactions with climate and vegetation indices in eastern Amazon, using data from NASA's Orbiting Carbon Observatory-2 (OCO-2). The study covered the period from January 2015 to December 2018. The data were subjected to regression, correlation, and temporal analysis, identifying the spatial distribution of hot/cold moments and hot/cold spots. In addition, anomalies were calculated to identify potential CO2 sources and sinks. Temporal changes indicate atmospheric Xco2 in the range from 362.2 to 403.4 ppm. Higher Xco2 values (hot moments) were concentrated between May and September, with some peaks in December. The lowest values (cold moments) were concentrated from November to April. SIF 771 W m-2 sr-1 μm-1 explained the temporal changes of Xco2 in 58% (R2 adj = 0.58; p < 0.001) and precipitation in 27% (R2 adj = 0.27; p ≤ 0.001). Spatial hot spots with 90% confidence were more representative in 2016. The maximum and minimum Xco2 (ppm) anomalies were 6.19 ppm (source) and -6.29 ppm (sink), respectively. We conclude that the hot moments of Xco2 in the eastern Amazon rainforest are concentrated in the dry season of the year. Xco2 spatial hot spots and anomalies are concentrated in the southern region and close to protected areas of the Amazon rainforest.
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Affiliation(s)
- Gustavo André de Araújo Santos
- Campus Avançado Porto Franco, Instituto Federal de Educação, Ciência e Tecnologia Do Maranhão - IFMA, Rua Custódio Barbosa, Nº 09, Centro, Porto Franco, Maranhão, 65.970-000, Brazil; Center of Agricultural, Natural and Literary Sciences, State University of the Tocantina Region of Maranhão (UEMASUL), Av. Brejo Do Pinto, S/N - Brejo Do Pinto, Estreito, Maranhão, 65975-000, Brazil; Department of Engineering and Exact Sciences, São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane S/n, 14884-900 Jaboticabal, São Paulo, Brazil.
| | - Luiz Fernando Favacho Morais Filho
- Department of Engineering and Exact Sciences, São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane S/n, 14884-900 Jaboticabal, São Paulo, Brazil
| | - Kamila Cunha de Meneses
- Department of Engineering and Exact Sciences, São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane S/n, 14884-900 Jaboticabal, São Paulo, Brazil
| | | | - Glauco de Souza Rolim
- Department of Engineering and Exact Sciences, São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane S/n, 14884-900 Jaboticabal, São Paulo, Brazil
| | - Newton La Scala
- Department of Engineering and Exact Sciences, São Paulo State University (FCAV-UNESP), Via de Acesso Prof. Paulo Donato Castellane S/n, 14884-900 Jaboticabal, São Paulo, Brazil
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Zhan C, Orth R, Migliavacca M, Zaehle S, Reichstein M, Engel J, Rammig A, Winkler AJ. Emergence of the physiological effects of elevated CO 2 on land-atmosphere exchange of carbon and water. GLOBAL CHANGE BIOLOGY 2022; 28:7313-7326. [PMID: 36097831 DOI: 10.1111/gcb.16397] [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: 03/14/2022] [Accepted: 07/12/2022] [Indexed: 06/15/2023]
Abstract
Elevated atmospheric CO2 (eCO2 ) influences the carbon assimilation rate and stomatal conductance of plants, thereby affecting the global cycles of carbon and water. Yet, the detection of these physiological effects of eCO2 in observational data remains challenging, because natural variations and confounding factors (e.g., warming) can overshadow the eCO2 effects in observational data of real-world ecosystems. In this study, we aim at developing a method to detect the emergence of the physiological CO2 effects on various variables related to carbon and water fluxes. We mimic the observational setting in ecosystems using a comprehensive process-based land surface model QUINCY to simulate the leaf-level effects of increasing atmospheric CO2 concentrations and their century-long propagation through the terrestrial carbon and water cycles across different climate regimes and biomes. We then develop a statistical method based on the signal-to-noise ratio to detect the emergence of the eCO2 effects. The eCO2 effect on gross primary productivity (GPP) emerges at relatively low CO2 increase (∆[CO2 ] ~ 20 ppm) where the leaf area index is relatively high. Compared to GPP, the eCO2 effect causing reduced transpiration water flux (normalized to leaf area) emerges only at relatively high CO2 increase (∆[CO2 ] >> 40 ppm), due to the high sensitivity to climate variability and thus lower signal-to-noise ratio. In general, the response to eCO2 is detectable earlier for variables related to the carbon cycle than the water cycle, when plant productivity is not limited by climatic constraints, and stronger in forest-dominated rather than in grass-dominated ecosystems. Our results provide a step toward when and where we expect to detect physiological CO2 effects in in-situ flux measurements, how to detect them and encourage future efforts to improve the understanding and quantification of these effects in observations of terrestrial carbon and water dynamics.
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Affiliation(s)
- Chunhui Zhan
- Department for Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - René Orth
- Department for Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Mirco Migliavacca
- Department for Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
- European Commission, Joint Research Centre, Ispra, Italy
| | - Sönke Zaehle
- Department of Biogeochemical Signals, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Markus Reichstein
- Department for Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Jan Engel
- Department of Biogeochemical Signals, Max Planck Institute for Biogeochemistry, Jena, Germany
| | - Anja Rammig
- Land Surface-Atmosphere Interactions, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Alexander J Winkler
- Department for Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
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36
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Brychkova G, Kekae K, McKeown PC, Hanson J, Jones CS, Thornton P, Spillane C. Climate change and land-use change impacts on future availability of forage grass species for Ethiopian dairy systems. Sci Rep 2022; 12:20512. [PMID: 36443389 PMCID: PMC9705545 DOI: 10.1038/s41598-022-23461-w] [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: 03/30/2021] [Accepted: 10/31/2022] [Indexed: 11/29/2022] Open
Abstract
Forage grasses are central feed resources for livestock globally. In Ethiopian dairy systems, they serve as feed sources during both wet and dry seasons, yet escalating climate change could threaten forage supply. Here, we investigate projected climate change impacts on three forage grasses currently recommended for Ethiopian dairy systems. We determine areas of geographical suitability for each species using three climate projections generated by General Circulation Models (GCMs) and calculate their ability to meet predicted dry matter demand under four scenarios for livestock intensification and land availability. By 2050, Buffel grass (Cenchrus ciliaris) is likely to be negatively affected by climate change in regions such as Tigray, while Rhodes grass (Chloris gayana) and Napier grass (Cenchrus purpureus) may have improved suitability under future climates. Our findings suggest that feed demands could theoretically be met by production of these forage grasses under current and future climates. However, if land availability is reduced and herd composition shifts towards higher-productivity exotic breeds, forage resources will not meet cattle demand even with improved agronomic management.
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Affiliation(s)
- Galina Brychkova
- Agriculture and Bioeconomy Research Centre, Ryan Institute, University of Galway, University Road, Galway, H91 REW4 Ireland
| | - Kelebogile Kekae
- Agriculture and Bioeconomy Research Centre, Ryan Institute, University of Galway, University Road, Galway, H91 REW4 Ireland
| | - Peter C. McKeown
- Agriculture and Bioeconomy Research Centre, Ryan Institute, University of Galway, University Road, Galway, H91 REW4 Ireland
| | - Jean Hanson
- grid.419369.00000 0000 9378 4481CGIAR Research Program On Climate Change, Agriculture and Food Security (CCAFS), International Livestock Research Institute (ILRI), Nairobi, Kenya
| | - Chris S. Jones
- grid.419369.00000 0000 9378 4481CGIAR Research Program On Climate Change, Agriculture and Food Security (CCAFS), International Livestock Research Institute (ILRI), Nairobi, Kenya
| | - Philip Thornton
- grid.419369.00000 0000 9378 4481CGIAR Research Program On Climate Change, Agriculture and Food Security (CCAFS), International Livestock Research Institute (ILRI), Nairobi, Kenya
| | - Charles Spillane
- Agriculture and Bioeconomy Research Centre, Ryan Institute, University of Galway, University Road, Galway, H91 REW4 Ireland
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Huntington TG, Shanley JB. A systematic increase in the slope of the concentration discharge relation for dissolved organic carbon in a forested catchment in Vermont, USA. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 844:156954. [PMID: 35760172 DOI: 10.1016/j.scitotenv.2022.156954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 06/20/2022] [Accepted: 06/21/2022] [Indexed: 06/15/2023]
Abstract
The production, mobilization and fluvial transport of dissolved organic carbon (DOC) in temperate forests are important components of the carbon cycle that are influenced by ongoing changes in climate. Numerous studies have reported temporal trends in stream water DOC concentrations and have attributed changes in concentrations to climatic and hydrologic variables. Fewer studies have reported trends in concentration-discharge (C-Q) relations for DOC. The goal of this study was to detect and quantify changes in DOC concentration and slope of the C-Q relation from 1991 to 2018 in an intensively sampled forested research watershed in northern Vermont. Stream water DOC concentration and slope of the C-Q relation increased over time as did precipitation, stream discharge, and air temperature. The increases in DOC concentration and slope of the C-Q were substantially greater in the summer and fall (autumn) than in winter and spring. The largest increases in the magnitude of C-Q slopes occurred in the December, October and September. The increases in slope of the C-Q relation in summer and fall were larger for baseflow than for storm flow. The increases in DOC concentration and slope of the C-Q relation over time may be related to increasing temperature, longer growing seasons, and associated increases in production and microbial decomposition of soil organic matter that supplies DOC for mobilization to streams. The results suggest that in a changing climate, C-Q relations may not necessarily be stationary and therefore analyses that attempt to estimate future DOC concentrations and loads should consider potentially changing C-Q relations over time.
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Affiliation(s)
- Thomas G Huntington
- U. S. Geological Survey, New England Water Science Center, 196 Whitten Rd., Augusta, Maine 04330, USA.
| | - James B Shanley
- U. S. Geological Survey, New England Water Science Center, 87 State Street, Montpelier, VT 05602, USA
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38
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Davis EC, Sohngen B, Lewis DJ. The effect of carbon fertilization on naturally regenerated and planted US forests. Nat Commun 2022; 13:5490. [PMID: 36123337 PMCID: PMC9485135 DOI: 10.1038/s41467-022-33196-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 09/08/2022] [Indexed: 11/24/2022] Open
Abstract
Over the last half century in the United States, the per-hectare volume of wood in trees has increased, but it is not clear whether this increase has been driven by forest management, forest recovery from past land uses, such as agriculture, or other environmental factors such as elevated carbon dioxide, nitrogen deposition, or climate change. This paper uses empirical analysis to estimate the effect of elevated carbon dioxide on aboveground wood volume in temperate forests of the United States. To accomplish this, we employ matching techniques that allow us to disentangle the effects of elevated carbon dioxide from other environmental factors affecting wood volume and to estimate the effects separately for planted and natural stands. We show that elevated carbon dioxide has had a strong and consistently positive effect on wood volume while other environmental factors yielded a mix of both positive and negative effects. This study, by enabling a better understanding of how elevated carbon dioxide and other anthropogenic factors are influencing forest stocks, can help policymakers and other stakeholders better account for the role of forests in Nationally Determined Contributions and global mitigation pathways to achieve a 1.5 degree Celsius target. The CO2 fertilisation effect in forests remains controversial. Here, the authors disentangle the effect of CO2 on forest wood volume from other environmental factors, showing that elevated CO2 had a positive effect on wood volume in planted and natural US temperate forests.
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Affiliation(s)
- Eric C Davis
- United States Department of Agriculture-Economic Research Service, Kansas City, MO, 64105, USA.
| | - Brent Sohngen
- Department of Agricultural, Environmental, and Development Economics, The Ohio State University, Columbus, OH, 43210, USA
| | - David J Lewis
- Department of Applied Economics, College of Agricultural Sciences, Oregon State University, Corvallis, OR, 97331, USA
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Sun W, Berry JA, Yakir D, Seibt U. Leaf relative uptake of carbonyl sulfide to CO 2 seen through the lens of stomatal conductance-photosynthesis coupling. THE NEW PHYTOLOGIST 2022; 235:1729-1742. [PMID: 35478172 DOI: 10.1111/nph.18178] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 04/16/2022] [Indexed: 06/14/2023]
Abstract
Carbonyl sulfide (COS) has emerged as a multi-scale tracer for terrestrial photosynthesis. To infer ecosystem-scale photosynthesis from COS fluxes often requires knowledge of leaf relative uptake (LRU), the concentration-normalized ratio between leaf COS uptake and photosynthesis. However, current mechanistic understanding of LRU variability remains inadequate for deriving robust COS-based estimates of photosynthesis. We derive a set of closed-form equations to describe LRU responses to light, humidity and CO2 based on the Ball-Berry stomatal conductance model and the biochemical model of photosynthesis. This framework reproduces observed LRU responses: decreasing LRU with increasing light or decreasing humidity; it also predicts that LRU increases with ambient CO2 . By fitting the LRU equations to flux measurements on a C3 reed (Typha latifolia), we obtain physiological parameters that control LRU variability, including an estimate of the Ball-Berry slope of 7.1 without using transpiration measurements. Sensitivity tests reveal that LRU is more sensitive to photosynthetic capacity than to the Ball-Berry slope, indicating stomatal response to photosynthesis. This study presents a simple framework for interpreting observed LRU variability and upscaling LRU. The stoma-regulated LRU response to CO2 suggests that COS may offer a unique window into long-term stomatal acclimation to elevated CO2 .
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Affiliation(s)
- Wu Sun
- Department of Global Ecology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA, 94305, USA
| | - Joseph A Berry
- Department of Global Ecology, Carnegie Institution for Science, 260 Panama Street, Stanford, CA, 94305, USA
| | - Dan Yakir
- Earth and Planetary Science, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Ulli Seibt
- Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, 520 Portola Plaza, Los Angeles, CA, 90095-1565, USA
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40
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Liu C, Wu Z, Hu Z, Yin N, Islam ARMT, Wei Z. Characteristics and influencing factors of carbon fluxes in winter wheat fields under elevated CO 2 concentration. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 307:119480. [PMID: 35588957 DOI: 10.1016/j.envpol.2022.119480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 05/03/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
Elevated carbon dioxide (ECO2) concentration has profound impacts on ecosystem carbon fluxes, with consequent changes in carbon sequestration and its feedback to climate change. Agroecosystem plays an essential role in global carbon sequestration. However, it is not well understood how the carbon fluxes of agroecosystem respond to increasing atmospheric CO2 concentrations. In this study, an in-situ 2-year field experiment was conducted using open-top chamber with treatments including ambient CO2 concentration (CK) and ambient plus 200 μmol mol-1 (T) to investigate the characteristics and main factors influencing carbon fluxes during the 2017-2019 winter wheat growing seasons. Results showed that the dynamics of CO2 fluxes under different treatments had similar seasonal trends, with the peak flux observed at the heading-filling stage. Compared to the CK, T treatment increased the cumulative amount of CO2 (CAC) by 17.2% and 24.0% in 2017-2018 and 2018-2019 growing seasons, respectively. In addition, the seasonal CAC was highly dependent on treatment and varied with year, while there was no interactive effect of treatment and year (p > 0.05). ECO2 concentration increased the biomass of wheat by an average of 8.28% over two growing seasons. There was a significant positive correlation between biomass and CAC, with biomass elucidating 52% and 76% of the variations in CAC under CK and T treatments, respectively. A good correlation was found between net ecosystem exchange (NEE) and environmental variables under different treatments. During the pre-milk ripening period, the NEE mainly depended on photosynthetically active radiation (PAR) and air temperature (Ta), while NEE was mainly controlled by PAR and soil water content (SWC) during the post-milk ripening period. Overall, the findings presented here demonstrate that the carbon exchange in wheat fields under different treatments serves as carbon sequestration, while ECO2 concentration enhances the capacity of winter wheat fields to act as carbon sinks, which may have feedback to the climate system in the future.
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Affiliation(s)
- Chao Liu
- Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Jiangsu Key Laboratory of Agricultural Meteorology, School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China.
| | - Zhurong Wu
- Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Jiangsu Key Laboratory of Agricultural Meteorology, School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Zhenghua Hu
- Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Jiangsu Key Laboratory of Agricultural Meteorology, School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China.
| | - Nan Yin
- Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Jiangsu Key Laboratory of Agricultural Meteorology, School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - A R M Towfiqul Islam
- Department of Disaster Management, Begum Rokeya University, Rangpur, 5400, Bangladesh
| | - Zhaowei Wei
- Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Jiangsu Key Laboratory of Agricultural Meteorology, School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China
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41
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Recurrent droughts increase risk of cascading tipping events by outpacing adaptive capacities in the Amazon rainforest. Proc Natl Acad Sci U S A 2022; 119:e2120777119. [PMID: 35917341 PMCID: PMC9371734 DOI: 10.1073/pnas.2120777119] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Tipping elements are nonlinear subsystems of the Earth system that have the potential to abruptly shift to another state if environmental change occurs close to a critical threshold with large consequences for human societies and ecosystems. Among these tipping elements may be the Amazon rainforest, which has been undergoing intensive anthropogenic activities and increasingly frequent droughts. Here, we assess how extreme deviations from climatological rainfall regimes may cause local forest collapse that cascades through the coupled forest-climate system. We develop a conceptual dynamic network model to isolate and uncover the role of atmospheric moisture recycling in such tipping cascades. We account for heterogeneity in critical thresholds of the forest caused by adaptation to local climatic conditions. Our results reveal that, despite this adaptation, a future climate characterized by permanent drought conditions could trigger a transition to an open canopy state particularly in the southern Amazon. The loss of atmospheric moisture recycling contributes to one-third of the tipping events. Thus, by exceeding local thresholds in forest adaptive capacity, local climate change impacts may propagate to other regions of the Amazon basin, causing a risk of forest shifts even in regions where critical thresholds have not been crossed locally.
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Braghiere RK, Fisher JB, Allen K, Brzostek E, Shi M, Yang X, Ricciuto DM, Fisher RA, Zhu Q, Phillips RP. Modeling Global Carbon Costs of Plant Nitrogen and Phosphorus Acquisition. JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS 2022; 14:e2022MS003204. [PMID: 36245670 PMCID: PMC9539603 DOI: 10.1029/2022ms003204] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 08/02/2022] [Accepted: 08/06/2022] [Indexed: 06/16/2023]
Abstract
Most Earth system models (ESMs) do not explicitly represent the carbon (C) costs of plant nutrient acquisition, which leads to uncertainty in predictions of the current and future constraints to the land C sink. We integrate a plant productivity-optimizing nitrogen (N) and phosphorus (P) acquisition model (fixation & uptake of nutrients, FUN) into the energy exascale Earth system (E3SM) land model (ELM). Global plant N and P uptake are dynamically simulated by ELM-FUN based on the C costs of nutrient acquisition from mycorrhizae, direct root uptake, retranslocation from senescing leaves, and biological N fixation. We benchmarked ELM-FUN with three classes of products: ILAMB, a remotely sensed nutrient limitation product, and CMIP6 models; we found significant improvements in C cycle variables, although the lack of more observed nutrient data prevents a comprehensive level of benchmarking. Overall, we found N and P co-limitation for 80% of land area, with the remaining 20% being either predominantly N or P limited. Globally, the new model predicts that plants invested 4.1 Pg C yr-1 to acquire 841.8 Tg N yr-1 and 48.1 Tg P yr-1 (1994-2005), leading to significant downregulation of global net primary production (NPP). Global NPP is reduced by 20% with C costs of N and 50% with C costs of NP. Modeled and observed nutrient limitation agreement increases when N and P are considered together (r 2 from 0.73 to 0.83).
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Affiliation(s)
- R. K. Braghiere
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
- Joint Institute for Regional Earth System Science and EngineeringUniversity of California Los AngelesLos AngelesCAUSA
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - J. B. Fisher
- Schmid College of Science and TechnologyChapman UniversityOrangeCAUSA
| | - K. Allen
- Manaaki Whenua—Landcare ResearchLincolnNew Zealand
| | - E. Brzostek
- Department of BiologyWest Virginia UniversityMorgantownWVUSA
| | - M. Shi
- Pacific Northwest National LaboratoryRichlandWAUSA
| | - X. Yang
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTNUSA
| | - D. M. Ricciuto
- Environmental Sciences Division and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTNUSA
| | - R. A. Fisher
- Center for International Climate ResearchOsloNorway
- Laboratoire Évolution & Diversité BiologiqueCNRS:UMRUniversité Paul SabatierToulouseFrance
| | - Q. Zhu
- Climate and Ecosystem Sciences DivisionClimate Sciences DepartmentLawrence Berkeley National LaboratoryBerkeleyCAUSA
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Increasing Impact of Precipitation on Alpine-Grassland Productivity over Last Two Decades on the Tibetan Plateau. REMOTE SENSING 2022. [DOI: 10.3390/rs14143430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Understanding the importance of temperature and precipitation on plant productivity is beneficial, to reveal the potential impact of climate change on vegetation growth. Although some studies have quantified the response of vegetation productivity to climate change at local, regional, and global scales, changes in climatic constraints on vegetation productivity over time are not well understood. This study combines the normalized difference vegetation index (NDVI) and the net primary production (NPP) modeled by CASA during the plant-growing season, to quantify the interplay of climatic (growing-season temperature and precipitation, GST and GSP) constraints on alpine-grassland productivity on the Tibetan Plateau, as well as the temporal dynamics of these constraints. The results showed that (1) 42.2% and 36.3% of grassland NDVI and NPP on the Tibetan Plateau increased significantly from 2000 to 2019. GSP controlled grassland growth in dryland regions, while humid grasslands were controlled by the GST. (2) The response strength of the NDVI and NPP to precipitation (partial correlation coefficient RNDVI-GSP and RNPP-GSP) increased substantially between 2000 and 2019. Especially, the RNDVI-GSP and RNPP-GSP increased from 0.14 and 0.01 in the first 10year period (2000–2009) to 0.83 and 0.78 in the second 10-year period (2010–2019), respectively. As a result, the controlling factor for alpine-grassland productivity variations shifted from temperature during 2000–2009 to precipitation during 2010–2019. (3) The increase in precipitation constraints was mainly distributed in dryland regions of the plateau. This study highlights that the climatic constraints on alpine-grassland productivity might change under ongoing climate change, which helps the understanding of the ecological responses and helps predict how vegetation productivity changes in the future.
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Mo F, Ren C, Yu K, Zhou Z, Phillips RP, Luo Z, Zhang Y, Dang Y, Han J, Ye J, Vinay N, Liao Y, Xiong Y, Wen X. Global pattern of soil priming effect intensity and its environmental drivers. Ecology 2022; 103:e3790. [PMID: 35718753 DOI: 10.1002/ecy.3790] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 04/16/2022] [Accepted: 05/09/2022] [Indexed: 11/05/2022]
Abstract
The microbial priming effect - the decomposition of soil organic carbon (SOC) induced by plant inputs - has long been considered an important driver of SOC dynamics, yet we have limited understanding about the direction, intensitiy, and drivers of priming across ecosystem types and biomes. This gap hinders our ability to predict how shifts in litter inputs under global change can affect climate feedbacks. Here, we synthesized 18,919 observations of CO2 effluxes in 802 soils across the globe to test the relative effects (i.e., log response ratio; RR) of litter additions on native SOC decomposition, and identified the dominant environmental drivers in natural ecosystems and agricultural lands. Globally, litter additions enhanced native SOC decomposition (RR = 0.35, 95% CI: 0.32 ~ 0.38), with greater priming effects occurring with decreasing latitude, and more in agricultural soils (RR = 0.43) than in uncultivated soils (RR = 0.28). In natural ecosystems, soil pH and microbial community composition (e.g., bacteria:fungi ratio) were the best predictors of priming, with greater effects occurring in acidic, bacterial-dominated, sandy soils. In contrast, substrate properties of plant litter and soils were the most important drivers of priming in agricultural systems, as soils with high C:N ratio and those receiving large inputs of low quality litter had the highest priming effects. Collectively, our results suggest that while different factors may control priming effects, the ubquitious nature of priming means that alterations of litter quality and quantity owing to global changes will likely have consequences for global C cycling and climate forcing.
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Affiliation(s)
- Fei Mo
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Chengjie Ren
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Kailiang Yu
- High Meadows Environmental Institute, Princeton University, Princeton, NJ, USA
| | - Zhenghu Zhou
- Center for Ecological Research, Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, Northeast Forestry University, 26 Hexing Road, Harbin, China
| | - Richard P Phillips
- Department of Biology, Indiana University Bloomington, Bloomington, IM, USA
| | - Zhongkui Luo
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yeye Zhang
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Yuteng Dang
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Juan Han
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Jiansheng Ye
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Nangia Vinay
- International Center for Agricultural Research in the Dry Areas (ICARDA), P.O. Box 6299-10112, Rabat, Morocco
| | - Yuncheng Liao
- Collage of Agriculture, Shanxi Agricultural University, Taigu, China
| | - Youcai Xiong
- State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Xiaoxia Wen
- College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
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Three Decades of Gross Primary Production (GPP) in China: Variations, Trends, Attributions, and Prediction Inferred from Multiple Datasets and Time Series Modeling. REMOTE SENSING 2022. [DOI: 10.3390/rs14112564] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The accurate estimation of gross primary production (GPP) is crucial to understanding plant carbon sequestration and grasping the quality of the ecological environment. Nevertheless, due to the inconsistencies of current GPP products, the variations, trends and short-term predictions of GPP have not been sufficiently well studied. In this study, we explore the spatiotemporal variability and trends of GPP and its associated climatic and anthropogenic factors in China from 1982 to 2015, mainly based on the optimum light use efficiency (LUEopt) product. We also employ an autoregressive integrated moving average (ARIMA) model to forecast the monthly GPP for a one-year lead time. The results show that GPP experienced an upward trend of 2.268 g C/m2 per year during the studied period, that is, an increasing rate of 3.9% per decade since 1982. However, these trend changes revealed distinct heterogeneity across space and time. The positive trends were mainly distributed in the Yellow River and Huaihe River out of the nine major river basins in China. We found that the dynamics of GPP were concurrently affected by climate factors and human activities. While air temperature and leaf area index (LAI) played dominant roles at a national level, the effects of precipitation, downward shortwave radiation (SRAD), carbon dioxide (CO2) and aerosol optical depth (AOD) exhibited discrepancies in terms of degree and scope. The ARIMA model achieved satisfactory prediction performance in most areas, though the accuracy was influenced by both data values and data quality. The model can potentially be generalized for other biophysical parameters with distinct seasonality. Our findings are further verified and corroborated by four widely used GPP products, demonstrating a good consistency of GPP trends and prediction. Our analysis provides a robust framework for characterizing long-term GPP dynamics that shed light on the improved assessment of the environmental quality of terrestrial ecosystems.
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Abstract
Current models may be overestimating the sequestration potential of forests.
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Affiliation(s)
- Julia K Green
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, USA
| | - Trevor F Keenan
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, USA.,Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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Launiainen S, Katul GG, Leppä K, Kolari P, Aslan T, Grönholm T, Korhonen L, Mammarella I, Vesala T. Does growing atmospheric CO 2 explain increasing carbon sink in a boreal coniferous forest? GLOBAL CHANGE BIOLOGY 2022; 28:2910-2929. [PMID: 35112446 PMCID: PMC9544622 DOI: 10.1111/gcb.16117] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/04/2022] [Indexed: 05/27/2023]
Abstract
The terrestrial net ecosystem productivity (NEP) has increased during the past three decades, but the mechanisms responsible are still unclear. We analyzed 17 years (2001-2017) of eddy-covariance measurements of NEP, evapotranspiration (ET) and light and water use efficiency from a boreal coniferous forest in Southern Finland for trends and inter-annual variability (IAV). The forest was a mean annual carbon sink (252 [ ± 42] gC m-2a-1 ), and NEP increased at rate +6.4-7.0 gC m-2a-1 (or ca. +2.5% a-1 ) during the period. This was attributed to the increasing gross-primary productivity GPP and occurred without detectable change in ET. The start of annual carbon uptake period was advanced by 0.7 d a-1 , and increase in GPP and NEP outside the main growing season contributed ca. one-third and one-fourth of the annual trend, respectively. Meteorological factors were responsible for the IAV of fluxes but did not explain the long-term trends. The growing season GPP trend was strongest in ample light during the peak growing season. Using a multi-layer ecosystem model, we showed that direct CO2 fertilization effect diminishes when moving from leaf to ecosystem, and only 30-40% of the observed ecosystem GPP increase could be attributed to CO2 . The increasing trend in leaf-area index (LAI), stimulated by forest thinning in 2002, was the main driver of the enhanced GPP and NEP of the mid-rotation managed forest. It also compensated for the decrease of mean leaf stomatal conductance with increasing CO2 and LAI, explaining the apparent proportionality between observed GPP and CO2 trends. The results emphasize that attributing trends to their physical and physiological drivers is challenged by strong IAV, and uncertainty of LAI and species composition changes due to the dynamic flux footprint. The results enlighten the underlying mechanisms responsible for the increasing terrestrial carbon uptake in the boreal zone.
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Affiliation(s)
| | - Gabriel G. Katul
- Department of Civil and Environmental EngineeringDuke UniversityDurhamNorth CarolinaUSA
| | - Kersti Leppä
- Natural Resources Institute FinlandHelsinkiFinland
| | - Pasi Kolari
- Faculty of ScienceInstitute for Atmospheric and Earth System Research/PhysicsUniversity of HelsinkiHelsinkiFinland
| | - Toprak Aslan
- Faculty of ScienceInstitute for Atmospheric and Earth System Research/PhysicsUniversity of HelsinkiHelsinkiFinland
| | | | | | - Ivan Mammarella
- Faculty of ScienceInstitute for Atmospheric and Earth System Research/PhysicsUniversity of HelsinkiHelsinkiFinland
| | - Timo Vesala
- Faculty of ScienceInstitute for Atmospheric and Earth System Research/PhysicsUniversity of HelsinkiHelsinkiFinland
- Faculty of Agriculture and ForestryInstitute for Atmospheric and Earth System Research/Forest SciencesUniversity of HelsinkiHelsinkiFinland
- Yugra State UniversityKhanty‐MansiyskRussia
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Shin Y, Midgley GF, Archer ERM, Arneth A, Barnes DKA, Chan L, Hashimoto S, Hoegh‐Guldberg O, Insarov G, Leadley P, Levin LA, Ngo HT, Pandit R, Pires APF, Pörtner H, Rogers AD, Scholes RJ, Settele J, Smith P. Actions to halt biodiversity loss generally benefit the climate. GLOBAL CHANGE BIOLOGY 2022; 28:2846-2874. [PMID: 35098619 PMCID: PMC9303674 DOI: 10.1111/gcb.16109] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 01/07/2022] [Accepted: 01/11/2022] [Indexed: 05/04/2023]
Abstract
The two most urgent and interlinked environmental challenges humanity faces are climate change and biodiversity loss. We are entering a pivotal decade for both the international biodiversity and climate change agendas with the sharpening of ambitious strategies and targets by the Convention on Biological Diversity and the United Nations Framework Convention on Climate Change. Within their respective Conventions, the biodiversity and climate interlinked challenges have largely been addressed separately. There is evidence that conservation actions that halt, slow or reverse biodiversity loss can simultaneously slow anthropogenic mediated climate change significantly. This review highlights conservation actions which have the largest potential for mitigation of climate change. We note that conservation actions have mainly synergistic benefits and few antagonistic trade-offs with climate change mitigation. Specifically, we identify direct co-benefits in 14 out of the 21 action targets of the draft post-2020 global biodiversity framework of the Convention on Biological Diversity, notwithstanding the many indirect links that can also support both biodiversity conservation and climate change mitigation. These relationships are context and scale-dependent; therefore, we showcase examples of local biodiversity conservation actions that can be incentivized, guided and prioritized by global objectives and targets. The close interlinkages between biodiversity, climate change mitigation, other nature's contributions to people and good quality of life are seldom as integrated as they should be in management and policy. This review aims to re-emphasize the vital relationships between biodiversity conservation actions and climate change mitigation in a timely manner, in support to major Conferences of Parties that are about to negotiate strategic frameworks and international goals for the decades to come.
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Affiliation(s)
| | - Guy F. Midgley
- School for Climate Studies, Department of Botany and ZoologyStellenbosch UniversityStellenboschSouth Africa
| | - Emma R. M. Archer
- Department of GeographyGeo‐Informatics and MeteorologyUniversity of PretoriaHatfield, PretoriaSouth Africa
| | - Almut Arneth
- Atmospheric Environmental ResearchKarlsruhe Institute of Technology (KIT)Garmisch‐PartenkirchenGermany
| | | | - Lena Chan
- International Biodiversity Conservation DivisionNational Parks BoardSingaporeSingapore
| | | | - Ove Hoegh‐Guldberg
- School of Biological Sciences and ARC Centre of Excellence for Coral Reef StudiesThe University of QueenslandBrisbaneQueenslandAustralia
| | - Gregory Insarov
- Institute of Geography of the Russian Academy for SciencesMoscowRussia
| | - Paul Leadley
- Laboratoire d’Ecologie Systématique EvolutionUniversité Paris‐Saclay, CNRS, AgroParisTechOrsayFrance
| | - Lisa A. Levin
- Center for Marine Biodiversity and Conservation and Integrative Oceanography DivisionScripps Institution of OceanographyUniversity of CaliforniaSan DiegoCaliforniaUSA
| | - Hien T. Ngo
- Office of Climate Change, Biodiversity and Environment, Food and Agriculture Organization of the United NationsRomeItaly
- Intergovernmental Science‐Policy Platform on Biodiversity and Ecosystem Services (IPBES)BonnGermany
| | - Ram Pandit
- Centre for Environmental Economics and PolicyUWA School of Agriculture and EnvironmentThe University of Western AustraliaCrawleyWestern AustraliaAustralia
- Global Center for Food, Land and Water ResourcesResearch Faculty of AgricultureHokkaido UniversitySapporoHokkaidoJapan
| | - Aliny P. F. Pires
- Department of Ecology – IBRAGRio de Janeiro State University (UERJ)Rio de JaneiroBrazil
| | - Hans‐Otto Pörtner
- Alfred Wegener Institute for Polar and Marine ResearchBremerhavenGermany
| | | | - Robert J. Scholes
- Global Change InstituteUniversity of the WitwatersrandJohannesburgSouth Africa
| | - Josef Settele
- Department of Conservation Biology and Social‐Ecological SystemsHelmholtz Centre for Environmental Research—UFZHalleGermany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐LeipzigLeipzigGermany
| | - Pete Smith
- Institute of Biological and Environmental SciencesUniversity of AberdeenAberdeenUK
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Terrestrial carbon sinks in China and around the world and their contribution to carbon neutrality. SCIENCE CHINA. LIFE SCIENCES 2022; 65:861-895. [PMID: 35146581 DOI: 10.1007/s11427-021-2045-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 12/13/2021] [Indexed: 01/04/2023]
Abstract
Enhancing the terrestrial ecosystem carbon sink (referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide (CO2) concentration and to achieve carbon neutrality target. To better understand the characteristics of terrestrial C sinks and their contribution to carbon neutrality, this review summarizes major progress in terrestrial C budget researches during the past decades, clarifies spatial patterns and drivers of terrestrial C sources and sinks in China and around the world, and examines the role of terrestrial C sinks in achieving carbon neutrality target. According to recent studies, the global terrestrial C sink has been increasing from a source of (-0.2±0.9) Pg C yr-1 (1 Pg=1015 g) in the 1960s to a sink of (1.9±1.1) Pg C yr-1 in the 2010s. By synthesizing the published data, we estimate terrestrial C sink of 0.20-0.25 Pg C yr-1 in China during the past decades, and predict it to be 0.15-0.52 Pg C yr-1 by 2060. The terrestrial C sinks are mainly located in the mid- and high latitudes of the Northern Hemisphere, while tropical regions act as a weak C sink or source. The C balance differs much among ecosystem types: forest is the major C sink; shrubland, wetland and farmland soil act as C sinks; and whether the grassland functions as C sink or source remains unclear. Desert might be a C sink, but the magnitude and the associated mechanisms are still controversial. Elevated atmospheric CO2 concentration, nitrogen deposition, climate change, and land cover change are the main drivers of terrestrial C sinks, while other factors such as fires and aerosols would also affect ecosystem C balance. The driving factors of terrestrial C sink differ among regions. Elevated CO2 concentration and climate change are major drivers of the C sinks in North America and Europe, while afforestation and ecological restoration are additionally important forcing factors of terrestrial C sinks in China. For future studies, we recommend the necessity for intensive and long term ecosystem C monitoring over broad geographic scale to improve terrestrial biosphere models for accurately evaluating terrestrial C budget and its dynamics under various climate change and policy scenarios.
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50
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Wang Z, Huang M, Gong H, Li X, Zhang H, Zhou X. Increased tropical vegetation respiration is dually induced by El Niño and upper atmospheric warm anomalies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 818:151719. [PMID: 34822906 DOI: 10.1016/j.scitotenv.2021.151719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 11/04/2021] [Accepted: 11/12/2021] [Indexed: 06/13/2023]
Abstract
Tropical vegetation respiration (TVR) is affected by extreme climate change. As it is very difficult to directly observe TVR, our understanding of the land-ocean-atmosphere carbon cycle, and particularly the regulatory effect of El Niño-Southern Oscillation (ENSO) on TVR and the land-atmosphere carbon balance, is very limited. Therefore, usingModerate Resolution Imaging Spectroradiometer (MODIS) products and meteorological data, we investigated the response of TVR to changes in ENSO during 2000-2015. The influence of El Niño on TVR was approximately 10.8% higher than that of La Niña. During El Niño years, a significant and anomalous increase in thermal measures related to TVR and ENSO and a significant and anomalous decrease in related hydrological measures favor the formation of warmer and drier climate conditions. Furthermore, the zonal distributions of air temperature and vertical velocity at 200-1000 hPa during El Niño years show that a stronger atmospheric inversion over tropical regions causes an increase in the surface temperature. Moreover, anomalous atmospheric subsidence inhibits the upward transport of water vapor, leading to a decrease in the cloud formation probability and reduced precipitation. In summary, increased surface temperatures caused by increased solar radiation and enhanced atmospheric inversion and decreased precipitation cause warmer and drier climate conditions, which forces TVR to increase. As TVR constitutes the key node of the land-atmosphere‑carbon cycle process, we focus on TVR and its close linkage with ENSO events and further establish a knowledge framework for understanding the land-atmosphere-ocean carbon cycle. This study deepens our understanding of not only the mechanism of the land-atmosphere carbon balance but also the ocean-induced terrestrial ecosystem processes spurred by ENSO-involved climate change. PLAIN LANGUAGE SUMMARY: Vegetation respiration regulates the carbon balance of the land and atmosphere. As it is very difficult to directly observe vegetation respiration, our understanding of the land-ocean-atmosphere carbon cycle involved and the roles of vegetation respiration and El Niño-Southern Oscillation (ENSO) in regulating the land-atmosphere carbon balance is very limited. Therefore, using MODIS products and meteorological data, we investigated the response of tropical vegetation respiration to changes in ENSO during 2000-2015. We found that during El Niño years, warmer and drier climate conditions over tropical regions increased vegetation respiration. Exacerbating the warmer and drier climate conditions, upper atmospheric warm anomalies further caused a remarkable increase in tropical vegetation respiration. Based on the land-atmosphere‑carbon cycle process, we establish a knowledge framework for understanding the land-atmosphere-ocean carbon cycle. This knowledge deepens our understanding of not only the mechanism of the land-atmosphere carbon balance but also the ocean-induced terrestrial ecosystem processes spurred by ENSO-involved climate change.
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Affiliation(s)
- Zhaosheng Wang
- National Ecosystem Science Data Center, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China; State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, Shaanxi, China
| | - Mei Huang
- National Ecosystem Science Data Center, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.
| | - He Gong
- National Ecosystem Science Data Center, Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Xinzhou Li
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, Shaanxi, China
| | - Hao Zhang
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
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