Geothermally warmed soils reveal persistent increases in the respiratory costs of soil microbes contributing to substantial C losses
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 c...
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ftcdlib:oai:escholarship.org/ark:/13030/qt7s75b008 2023-05-15T15:13:44+02:00 Geothermally warmed soils reveal persistent increases in the respiratory costs of soil microbes contributing to substantial C losses Marañón-Jiménez, S Soong, JL Leblans, NIW Sigurdsson, BD Peñuelas, J Richter, A Asensio, D Fransen, E Janssens, IA 245 - 260 2018-05-01 application/pdf https://escholarship.org/uc/item/7s75b008 unknown eScholarship, University of California qt7s75b008 https://escholarship.org/uc/item/7s75b008 public Biogeochemistry, vol 138, iss 3 Agronomy & Agriculture Other Chemical Sciences Geochemistry Environmental Science and Management article 2018 ftcdlib 2021-06-20T14:22:52Z 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 7years 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 (0–10cm) 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. Article in Journal/Newspaper Arctic Climate change Iceland University of California: eScholarship Arctic |
institution |
Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
unknown |
topic |
Agronomy & Agriculture Other Chemical Sciences Geochemistry Environmental Science and Management |
spellingShingle |
Agronomy & Agriculture Other Chemical Sciences Geochemistry Environmental Science and Management Marañón-Jiménez, S Soong, JL Leblans, NIW Sigurdsson, BD Peñuelas, J Richter, A Asensio, D Fransen, E Janssens, IA Geothermally warmed soils reveal persistent increases in the respiratory costs of soil microbes contributing to substantial C losses |
topic_facet |
Agronomy & Agriculture Other Chemical Sciences Geochemistry Environmental Science and Management |
description |
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 7years 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 (0–10cm) 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. |
format |
Article in Journal/Newspaper |
author |
Marañón-Jiménez, S Soong, JL Leblans, NIW Sigurdsson, BD Peñuelas, J Richter, A Asensio, D Fransen, E Janssens, IA |
author_facet |
Marañón-Jiménez, S Soong, JL Leblans, NIW Sigurdsson, BD Peñuelas, J Richter, A Asensio, D Fransen, E Janssens, IA |
author_sort |
Marañón-Jiménez, S |
title |
Geothermally warmed soils reveal persistent increases in the respiratory costs of soil microbes contributing to substantial C losses |
title_short |
Geothermally warmed soils reveal persistent increases in the respiratory costs of soil microbes contributing to substantial C losses |
title_full |
Geothermally warmed soils reveal persistent increases in the respiratory costs of soil microbes contributing to substantial C losses |
title_fullStr |
Geothermally warmed soils reveal persistent increases in the respiratory costs of soil microbes contributing to substantial C losses |
title_full_unstemmed |
Geothermally warmed soils reveal persistent increases in the respiratory costs of soil microbes contributing to substantial C losses |
title_sort |
geothermally warmed soils reveal persistent increases in the respiratory costs of soil microbes contributing to substantial c losses |
publisher |
eScholarship, University of California |
publishDate |
2018 |
url |
https://escholarship.org/uc/item/7s75b008 |
op_coverage |
245 - 260 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Climate change Iceland |
genre_facet |
Arctic Climate change Iceland |
op_source |
Biogeochemistry, vol 138, iss 3 |
op_relation |
qt7s75b008 https://escholarship.org/uc/item/7s75b008 |
op_rights |
public |
_version_ |
1766344267597348864 |