The temperature response of soil microbial efficiency and its feedback to climate Journal Article


Authors: Frey, Serita D.; Lee, Juhwan; Melillo, Jerry M.; Six, Johan
Article Title: The temperature response of soil microbial efficiency and its feedback to climate
Abstract: Soils are the largest repository of organic carbon (C) in the terrestrial biosphere and represent an important source of carbon dioxide (CO2) to the atmosphere, releasing 60-75 Pg C annually through microbial decomposition of organic materials(1,2). A primary control on soil CO2 flux is the efficiency with which the microbial community uses C. Despite its critical importance to soil-atmosphere CO2 exchange, relatively few studies have examined the factors controlling soil microbial efficiency. Here, we measured the temperature response of microbial efficiency in soils amended with substrates varying in lability. We also examined the temperature sensitivity of microbial efficiency in response to chronic soil warming in situ. We find that the efficiency with which soil microorganisms use organic matter is dependent on both temperature and substrate quality, with efficiency declining with increasing temperatures for more recalcitrant substrates. However, the utilization efficiency of a more recalcitrant substrate increased at higher temperatures in soils exposed to almost two decades of warming 5 degrees C above ambient. Our work suggests that climate warming could alter the decay dynamics of more stable organic matter compounds, thereby having a positive feedback to climate that is attenuated by a shift towards a more efficient microbial community in the longer term.
Keywords: MODEL; COMMUNITY; ORGANIC-MATTER; RESPIRATION; DECOMPOSITION; CARBON-CYCLE FEEDBACKS; Environmental Sciences Ecology; Meteorology Atmospheric Sciences; BACTERIAL-GROWTH EFFICIENCY
Journal Title: Nature Climate Change
Volume: 3
Issue: 4
ISSN: 1758-678X
Publisher: Nature Publishing Group  
Publication Place: LONDON; MACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLAND
Date Published: 2013
Start Page: 395
End Page: 398
Language: English
DOI/URL:
Notes: PT: J; NR: 28; TC: 13; J9: NAT CLIM CHANGE; PG: 4; GA: 150OL; UT: WOS:000319400400023