Biogeographic variation in temperature sensitivity of decomposition in forest soils

© 2019 John Wiley & Sons Ltd.

Détails bibliographiques
Publié dans:Global change biology. - 1999. - 26(2020), 3 vom: 14. März, Seite 1873-1885
Auteur principal: Li, Jinquan (Auteur)
Autres auteurs: Nie, Ming, Pendall, Elise, Reich, Peter B, Pei, Junmin, Noh, Nam Jin, Zhu, Ting, Li, Bo, Fang, Changming
Format: Article en ligne
Langue:English
Publié: 2020
Accès à la collection:Global change biology
Sujets:Journal Article Research Support, Non-U.S. Gov't Q10 carbon cycle carbon cycle modelling carbon decomposition climate change forest spatial heterogeneity temperature sensitivity plus... Soil Carbon 7440-44-0
Description
Résumé:© 2019 John Wiley & Sons Ltd.
Determining soil carbon (C) responses to rising temperature is critical for projections of the feedbacks between terrestrial ecosystems, C cycle, and climate change. However, the direction and magnitude of this feedback remain highly uncertain due largely to our limited understanding of the spatial heterogeneity of soil C decomposition and its temperature sensitivity. Here we quantified C decomposition and its response to temperature change with an incubation study of soils from 203 sites across tropical to boreal forests in China spanning a wide range of latitudes (18°16' to 51°37'N) and longitudes (81°01' to 129°28'E). Mean annual temperature (MAT) and mean annual precipitation primarily explained the biogeographic variation in the decomposition rate and temperature sensitivity of soils: soil C decomposition rate decreased from warm and wet forests to cold and dry forests, while Q10-MAT (standardized to the MAT of each site) values displayed the opposite pattern. In contrast, biological factors (i.e. plant productivity and soil bacterial diversity) and soil factors (e.g. clay, pH, and C availability of microbial biomass C and dissolved organic C) played relatively small roles in the biogeographic patterns. Moreover, no significant relationship was found between Q10-MAT and soil C quality, challenging the current C quality-temperature hypothesis. Using a single, fixed Q10-MAT value (the mean across all forests), as is usually done in model predictions, would bias the estimated soil CO2 emissions at a temperature increase of 3.0°C. This would lead to overestimation of emissions in warm biomes, underestimation in cold biomes, and likely significant overestimation of overall C release from soil to the atmosphere. Our results highlight that climate-related biogeographic variation in soil C responses to temperature needs to be included in next-generation C cycle models to improve predictions of C-climate feedbacks
Description:Date Completed 19.03.2020
Date Revised 19.03.2020
published: Print-Electronic
Citation Status MEDLINE
ISSN:1365-2486
DOI:10.1111/gcb.14838