Article

Similar Response of Labile and Resistant Soil Organic Matter Pools to Changes in Temperature

School of Biological Sciences, University of Aberdeen, Aberdeen AB24 3UU, UK.
Nature (Impact Factor: 41.46). 02/2005; 433(7021):57-9. DOI: 10.1038/nature03138
Source: PubMed

ABSTRACT

Our understanding of the relationship between the decomposition of soil organic matter (SOM) and soil temperature affects our predictions of the impact of climate change on soil-stored carbon. One current opinion is that the decomposition of soil labile carbon is sensitive to temperature variation whereas resistant components are insensitive. The resistant carbon or organic matter in mineral soil is then assumed to be unresponsive to global warming. But the global pattern and magnitude of the predicted future soil carbon stock will mainly rely on the temperature sensitivity of these resistant carbon pools. To investigate this sensitivity, we have incubated soils under changing temperature. Here we report that SOM decomposition or soil basal respiration rate was significantly affected by changes in SOM components associated with soil depth, sampling method and incubation time. We find, however, that the temperature sensitivity for SOM decomposition was not affected, suggesting that the temperature sensitivity for resistant organic matter pools does not differ significantly from that of labile pools, and that both types of SOM will therefore respond similarly to global warming.

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    • "However, previous studies have shown inconsistent patterns of Q 10 values of soil respiration with soil depth. Increase (Lomander et al. 1998; Fierer et al. 2003; Jin et al. 2008; Karhu et al. 2010), decrease (Winkler et al. 1996; MacDonald et al. 1999; Gillabel et al. 2010), or no changes (Fang et al. 2005; Leifeld and Fuhrer 2005; Rey et al. 2008) in apparent Q 10 values with increasing soil depth have been observed in different studies. Much of the variation in the apparent temperature sensitivity of SOC decomposition may be related to the fact that labile substrate availability is often unaccounted for in these studies (Davidson and Janssens 2006; Gershenson et al. 2009; Conant et al. 2011). "

    Full-text · Dataset · Dec 2015
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    • "However, previous studies have shown inconsistent patterns of Q 10 values of soil respiration with soil depth. Increase (Lomander et al. 1998; Fierer et al. 2003; Jin et al. 2008; Karhu et al. 2010), decrease (Winkler et al. 1996; MacDonald et al. 1999; Gillabel et al. 2010), or no changes (Fang et al. 2005; Leifeld and Fuhrer 2005; Rey et al. 2008) in apparent Q 10 values with increasing soil depth have been observed in different studies. Much of the variation in the apparent temperature sensitivity of SOC decomposition may be related to the fact that labile substrate availability is often unaccounted for in these studies (Davidson and Janssens 2006; Gershenson et al. 2009; Conant et al. 2011). "

    Full-text · Article · Oct 2015 · Biogeochemistry
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    • " Paul et al . , 1997 ; Schöning and Kögel - Knabner , 2006 ) . Little direct evidence has been provided showing that SOC stabilized under previous conditions will remain stable with changing conditions , such as with climate change , and some studies have shown that previously stable SOC may be rapidly mobilized to CO 2 ( Fontaine et al . , 2007 ; Fang et al . , 2005 ) ."
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