Suchergebnisse

The ICOS Ecosystem network is part of the ICOS European Research Infrastructure (www.icos-infrastructure.eu) together with the Atmospheric and Ocean networks. The ICOS Ecosystem includes highly standardized monitoring sites based on commercially available instruments embedded into an integrated system that is coordinated by the ICOS Ecosystem Thematic Center (ETC) which is responsible for the methodologies advancement, data processing and data distribution. The ecosystem monitoring activity will involve human intervention in field activities and for this reason rigorously standardized protocol for field ecosystem measurements are in preparation also in coordination with others international related activities. The core measurement in the ICOS Ecosystem sites are the main GHGs fluxes that include CO2, H2O, CH4 and N2O, using the eddy covariance method and chambers for the soil effluxes. To better interpret and understand the GHGs exchanges a full series of meteorological data (including spectral reflectance measurements and full radiation and water balance) are also collected and the sites are characterized in terms of carbon stocks, nutrients availability and management and disturbance history. Centralized raw data processing, QAQC and uncertainty estimation, test and development of new methodologies and techniques, assistance to the network and chemical analysis and long term storage of the vegetation and soil samples are the main activities where the ETC is responsible. The ETC, based in Italy and with sections in Belgium and France, is under construction and will be operative in 2013. The Ecosystem network, including the variables collected, the protocols under preparation and the data access and data use policies will be presented together with the Ecosystem Thematic Center role and development strategy. The aim is to identify and discuss integration and collaboration with others similar initiatives, also thanks to the support of the COOPEUS European project that will facilitate coordination between US and EU networks, and to receive the feedbacks from potential users of the infrastructure.

AbstractSoil microbes ultimately drive the mineralization of soil organic carbon and thus ecosystem functions. We compiled a dataset of the seasonality of microbial biomass carbon (MBC) and developed a semi-mechanistic model to map monthly MBC across the globe. MBC exhibits an equatorially symmetric seasonality between the Northern and Southern Hemispheres. In the Northern Hemisphere, MBC peaks in autumn and is minimal in spring at low latitudes (<25°N), peaks in the spring and is minimal in autumn at mid-latitudes (25°N to 50°N), while peaks in autumn and is minimal in spring at high latitudes (>50°N). This latitudinal shift of MBC seasonality is attributed to an interaction of soil temperature, soil moisture, and substrate availability. The MBC seasonality is inconsistent with patterns of heterotrophic respiration, indicating that MBC as a proxy for microbial activity is inappropriate at this resolution. This study highlights the need to explicitly represent microbial physiology in microbial models. The interactive controls of environments and substrate on microbial seasonality provide insights for better representing microbial mechanisms in simulating ecosystem functions at the seasonal scale.

This article is part of the FORHOT project ; Increasing temperatures can accelerate soil organic matter decomposition and release large amounts of CO2 to the atmosphere, potentially inducing positive warming feedbacks. Alterations to the temperature sensitivity and physiological functioning of soil microorganisms may play a key role in these carbon (C) losses. Geothermally active areas in Iceland provide stable and continuous soil temperature gradients to test this hypothesis, encompassing the full range of warming scenarios projected by the Intergovernmental Panel on Climate Change for the northern region. We took soils from these geothermal sites 7 years after the onset of warming and incubated them at varying temperatures and substrate availability conditions to detect persistent alterations of microbial physiology to long-term warming. Seven years of continuous warming ranging from 1.8 to 15.9 °C triggered a 8.6–58.0% decrease on the C concentrations in the topsoil (0–10 cm) of these sub-arctic silt-loam Andosols. The sensitivity of microbial respiration to temperature (Q10) was not altered. However, soil microbes showed a persistent increase in their microbial metabolic quotients (microbial respiration per unit of microbial biomass) and a subsequent diminished C retention in biomass. After an initial depletion of labile soil C upon soil warming, increasing energy costs of metabolic maintenance and resource acquisition led to a weaker capacity of C stabilization in the microbial biomass of warmer soils. This mechanism contributes to our understanding of the acclimated response of soil respiration to in situ soil warming at the ecosystem level, despite a lack of acclimation at the physiological level. Persistent increases in the respiratory costs of soil microbes in response to warming constitute a fundamental process that should be incorporated into climate change-C cycling models. ; This research was supported by the European Union's Seventh Framework Program, the Ministry of Economy, Innovation, Science and Employment of the Junta de Andalucía (postdoctoral fellowship of the Andalucía Talent Hub Program, Marie Skłodowska-Curie actions, COFUND—Grant Agreement No 291780, to SMJ), the European Research Council Synergy grant 610028 (IMBALANCE-P), the research project "GEISpain" (CGL2014-52838-C2-1-R) of the Spanish Ministry of Economy and Competitiveness and the Research Council of the University of Antwerp (FORHOT TOP-BOF project). This work contributes to the FSC-Sink, CAR-ES and ClimMani COST Action (ES1308). The Agricultural University of Iceland and Mogilsá—the Icelandic Forest Research, provided logistical support for the present study. We thank Matthias Meys, Sara Diels, Johan De Gruyter, Giovanni Dalmasso, Fabiana Quirós and Nadine Calluy for their invaluable help in the laboratory and Sara Vicca and James Weedon for their constructive suggestions. We further thank Anne Cools and Tom Van Der Spiet for their assistance with the lab chemical analyses. ; Peer Reviewed

Subterranean ecosystems play an active role in the global carbon cycle, yet only a few studies using indirect methods have focused on the role of the cave microbiota in this critical cycle. Here we present pioneering research based on in situ real-time monitoring of CO2 and CH4 diffusive fluxes and concurrent δ13C geochemical tracing in caves, combined with 16S microbiome analysis. Our findings show that cave sediments are promoting continuous CH4 consumption from cave atmosphere, resulting in a significant removal of 65% to 90%. This research reveals the most effective taxa and metabolic pathways in consumption and uptake of greenhouse gases. Methanotrophic bacteria were the most effective group involved in CH4 consumption, namely within the families Methylomonaceae, Methylomirabilaceae and Methylacidiphilaceae. In addition, Crossiella and Nitrosococcaceae wb1-P19 could be one of the main responsible of CO2 uptake, which occurs via the Calvin-Benson-Bassham cycle and reversible hydration of CO2. Thus, syntrophic relationships exist between Crossiella and nitrifying bacteria that capture CO2, consume inorganic N produced by heterotrophic ammonification in the surface of sediments, and induce moonmilk formation. Moonmilk is found as the most evolved phase of the microbial processes in cave sediments that fixes CO2 as calcite and intensifies CH4 oxidation. From an ecological perspective, cave sediments act qualitatively as soils, providing fundamental ecosystem services (e.g. nutrient cycling and carbon sequestration) with direct influence on greenhouse gas emissions. ; This work was supported by the Spanish Ministry of Science, Innovation through project PID2019-110603RB-I00, MCIN/AEI/FEDER UE/10.13039/501100011033 and with collaboration of projects RTI2018-099052-B-I00 and PID2020-114978GB-I00. This research has also received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 844535 — MIFLUKE. ; Peer reviewed

Climate change is stronger at high than at temperate and tropical latitudes. The natural geothermal conditions in southern Iceland provide an opportunity to study the impact of warming on plants, because of the geothermal bedrock channels that induce stable gradients of soil temperature. We studied two valleys, one where such gradients have been present for centuries (long-term treatment), and another where new gradients were created in 2008 after a shallow crustal earthquake (short-term treatment). We studied the impact of soil warming (0 to +15 C) on the foliar metabolomes of two common plant species of high northern latitudes: Agrostis capillaris, a monocotyledon grass; and Ranunculus acris, a dicotyledonous herb, and evaluated the dependence of shifts in their metabolomes on the length of the warming treatment. The two species responded differently to warming, depending on the length of exposure. The grass metabolome clearly shifted at the site of long-term warming, but the herb metabolome did not. The main up-regulated compounds at the highest temperatures at the long-term site were saccharides and amino acids, both involved in heat-shock metabolic pathways. Moreover, some secondary metabolites, such as phenolic acids and terpenes, associated with a wide array of stresses, were also up-regulated. Most current climatic models predict an increase in annual average temperature between 2–8 C over land masses in the Arctic towards the end of this century. The metabolomes of A. capillaris and R. acris shifted abruptly and nonlinearly to soil warming >5 C above the control temperature for the coming decades. These results thus suggest that a slight warming increase may not imply substantial changes in plant function, but if the temperature rises more than 5 C, warming may end up triggering metabolic pathways associated with heat stress in some plant species currently dominant in this region. ; This research was supported by the European Research Council Synergy grant ERC-2013-SyG-610028 IMBALANCE-P, the Spanish Government grant CGL2016-79835, the Catalan Government grant SGR 2014-274, the Scholarly Studies programme of the Smithsonian Institution, projects LM2015061 and LO1415 of the Ministry of Education, Youth and Sports of the Czech Republic, and the Research Foundation—Flanders (FWO aspirant grant to N.L.). ; Peer Reviewed

Subterranean ecosystems play an active role in the global carbon cycle, yet only a few studies using indirect methods have focused on the role of the cave microbiota in this critical cycle. Here we present pioneering research based on in situ real-time monitoring of CO2 and CH4 diffusive fluxes and concurrent δ13C geochemical tracing in caves, combined with 16S microbiome analysis. Our findings show that cave sediments are promoting continuous CH4 consumption from cave atmosphere, resulting in a significant removal of 65% to 90%. This research reveals the most effective taxa and metabolic pathways in consumption and uptake of greenhouse gases. Methanotrophic bacteria were the most effective group involved in CH4 consumption, namely within the families Methylomonaceae, Methylomirabilaceae and Methylacidiphilaceae. In addition, Crossiella and Nitrosococcaceae wb1-P19 could be one of the main responsible of CO2 uptake, which occurs via the Calvin-Benson-Bassham cycle and reversible hydration of CO2. Thus, syntrophic relationships exist between Crossiella and nitrifying bacteria that capture CO2, consume inorganic N produced by heterotrophic ammonification in the surface of sediments, and induce moonmilk formation. Moonmilk is found as the most evolved phase of the microbial processes in cave sediments that fixes CO2 as calcite and intensifies CH4 oxidation. From an ecological perspective, cave sediments act qualitatively as soils, providing fundamental ecosystem services (e.g. nutrient cycling and carbon sequestration) with direct influence on greenhouse gas emissions. ; This work was supported by the Spanish Ministry of Science, Innovation through project PID2019-110603RB-I00, MCIN/AEI/FEDER, UE/10.13039/501100011033 and with collaboration of projects RTI2018-099052-B-I00 and PID2020-114978GB-I00. This research has also received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 844535 — MIFLUKE.

International audience ; Natural gas use accounts for ≈38% of the fossil fuel CO 2 emissions in Europe, including the EU27 and UK (Eurostat, 2021). The share of this fossil fuel in the energy mix has been growing since 1990 at the expense of oil and coal, as it is viewed as a cleaner source of energy (IEA, 2021). The main sectors using natural gas are the built environment (residential, public and commercial buildings), the industry, and the electricity production (Eurostat, 2021). In addition to steadily growing natural gas use, the COVID-19 pandemic profoundly disrupted economic activities and the energy demand, beginning in early March of 2020. Specifically, the government policies restricted mobility and confined people at home during "lockdowns", and reduced or closed industrial and non-essential commercial activities, with impacts on gas use and pertaining CO 2 emissions. Although such impacts have been noted by recent reports (IEA, 2020a, 2020b), they have not yet been quantified and analyzed in detail. During the cold season period when the pandemic arrived in Europe, natural gas consumption is typically high due to the heating demand in the built environment, which represents 52% of the total gas consumption from all-sectors averaged over January to June. For both residential and commercial buildings, gas consumption is typically inversely proportional to daily air temperature when temperatures fall below a comfort threshold "critical

International audience ; Natural gas use accounts for ≈38% of the fossil fuel CO 2 emissions in Europe, including the EU27 and UK (Eurostat, 2021). The share of this fossil fuel in the energy mix has been growing since 1990 at the expense of oil and coal, as it is viewed as a cleaner source of energy (IEA, 2021). The main sectors using natural gas are the built environment (residential, public and commercial buildings), the industry, and the electricity production (Eurostat, 2021). In addition to steadily growing natural gas use, the COVID-19 pandemic profoundly disrupted economic activities and the energy demand, beginning in early March of 2020. Specifically, the government policies restricted mobility and confined people at home during "lockdowns", and reduced or closed industrial and non-essential commercial activities, with impacts on gas use and pertaining CO 2 emissions. Although such impacts have been noted by recent reports (IEA, 2020a, 2020b), they have not yet been quantified and analyzed in detail. During the cold season period when the pandemic arrived in Europe, natural gas consumption is typically high due to the heating demand in the built environment, which represents 52% of the total gas consumption from all-sectors averaged over January to June. For both residential and commercial buildings, gas consumption is typically inversely proportional to daily air temperature when temperatures fall below a comfort threshold "critical

International audience ; Natural gas use accounts for ≈38% of the fossil fuel CO 2 emissions in Europe, including the EU27 and UK (Eurostat, 2021). The share of this fossil fuel in the energy mix has been growing since 1990 at the expense of oil and coal, as it is viewed as a cleaner source of energy (IEA, 2021). The main sectors using natural gas are the built environment (residential, public and commercial buildings), the industry, and the electricity production (Eurostat, 2021). In addition to steadily growing natural gas use, the COVID-19 pandemic profoundly disrupted economic activities and the energy demand, beginning in early March of 2020. Specifically, the government policies restricted mobility and confined people at home during "lockdowns", and reduced or closed industrial and non-essential commercial activities, with impacts on gas use and pertaining CO 2 emissions. Although such impacts have been noted by recent reports (IEA, 2020a, 2020b), they have not yet been quantified and analyzed in detail. During the cold season period when the pandemic arrived in Europe, natural gas consumption is typically high due to the heating demand in the built environment, which represents 52% of the total gas consumption from all-sectors averaged over January to June. For both residential and commercial buildings, gas consumption is typically inversely proportional to daily air temperature when temperatures fall below a comfort threshold "critical

International audience ; Natural gas use accounts for ≈38% of the fossil fuel CO 2 emissions in Europe, including the EU27 and UK (Eurostat, 2021). The share of this fossil fuel in the energy mix has been growing since 1990 at the expense of oil and coal, as it is viewed as a cleaner source of energy (IEA, 2021). The main sectors using natural gas are the built environment (residential, public and commercial buildings), the industry, and the electricity production (Eurostat, 2021). In addition to steadily growing natural gas use, the COVID-19 pandemic profoundly disrupted economic activities and the energy demand, beginning in early March of 2020. Specifically, the government policies restricted mobility and confined people at home during "lockdowns", and reduced or closed industrial and non-essential commercial activities, with impacts on gas use and pertaining CO 2 emissions. Although such impacts have been noted by recent reports (IEA, 2020a, 2020b), they have not yet been quantified and analyzed in detail. During the cold season period when the pandemic arrived in Europe, natural gas consumption is typically high due to the heating demand in the built environment, which represents 52% of the total gas consumption from all-sectors averaged over January to June. For both residential and commercial buildings, gas consumption is typically inversely proportional to daily air temperature when temperatures fall below a comfort threshold "critical

International audience ; Natural gas use accounts for ≈38% of the fossil fuel CO 2 emissions in Europe, including the EU27 and UK (Eurostat, 2021). The share of this fossil fuel in the energy mix has been growing since 1990 at the expense of oil and coal, as it is viewed as a cleaner source of energy (IEA, 2021). The main sectors using natural gas are the built environment (residential, public and commercial buildings), the industry, and the electricity production (Eurostat, 2021). In addition to steadily growing natural gas use, the COVID-19 pandemic profoundly disrupted economic activities and the energy demand, beginning in early March of 2020. Specifically, the government policies restricted mobility and confined people at home during "lockdowns", and reduced or closed industrial and non-essential commercial activities, with impacts on gas use and pertaining CO 2 emissions. Although such impacts have been noted by recent reports (IEA, 2020a, 2020b), they have not yet been quantified and analyzed in detail. During the cold season period when the pandemic arrived in Europe, natural gas consumption is typically high due to the heating demand in the built environment, which represents 52% of the total gas consumption from all-sectors averaged over January to June. For both residential and commercial buildings, gas consumption is typically inversely proportional to daily air temperature when temperatures fall below a comfort threshold "critical

International audience ; As the COVID-19 virus spread over the world, governments restricted mobility to slow transmission. Public health measures had different intensities across European countries but all had significant impact on people's daily lives and economic activities, causing a drop of CO2 emissions of about 10% for the whole year 2020. Here, we analyze changes in natural gas use in the industry and gas distribution to the built environment during the first half of year 2020 with daily gas flows data from pipeline and storage facilities in Europe. We find that reductions of industrial gas use reflect decreases in industrial production across most countries. Surprisingly, natural gas use in the built environment also decreased despite most people being confined at home and cold spells in March 2020. Those reductions that we attribute to the impacts of COVID-19 remain of comparable magnitude to previous variations induced by cold or warm climate anomalies in the cold season. We conclude that climate variations played a larger role than COVID-19 induced stay-home orders in natural gas consumption across Europe.

International audience ; As the COVID-19 virus spread over the world, governments restricted mobility to slow transmission. Public health measures had different intensities across European countries but all had significant impact on people's daily lives and economic activities, causing a drop of CO2 emissions of about 10% for the whole year 2020. Here, we analyze changes in natural gas use in the industry and gas distribution to the built environment during the first half of year 2020 with daily gas flows data from pipeline and storage facilities in Europe. We find that reductions of industrial gas use reflect decreases in industrial production across most countries. Surprisingly, natural gas use in the built environment also decreased despite most people being confined at home and cold spells in March 2020. Those reductions that we attribute to the impacts of COVID-19 remain of comparable magnitude to previous variations induced by cold or warm climate anomalies in the cold season. We conclude that climate variations played a larger role than COVID-19 induced stay-home orders in natural gas consumption across Europe.

International audience ; As the COVID-19 virus spread over the world, governments restricted mobility to slow transmission. Public health measures had different intensities across European countries but all had significant impact on people's daily lives and economic activities, causing a drop of CO2 emissions of about 10% for the whole year 2020. Here, we analyze changes in natural gas use in the industry and gas distribution to the built environment during the first half of year 2020 with daily gas flows data from pipeline and storage facilities in Europe. We find that reductions of industrial gas use reflect decreases in industrial production across most countries. Surprisingly, natural gas use in the built environment also decreased despite most people being confined at home and cold spells in March 2020. Those reductions that we attribute to the impacts of COVID-19 remain of comparable magnitude to previous variations induced by cold or warm climate anomalies in the cold season. We conclude that climate variations played a larger role than COVID-19 induced stay-home orders in natural gas consumption across Europe.