|Appears in Collections:||Biological and Environmental Sciences Journal Articles|
|Peer Review Status:||Refereed|
|Title:||Does the temperature sensitivity of decomposition of soil organic matter depend upon water content, soil horizon, or incubation time?|
Angeli, Andrew C
Tenhunen, John D
|Publisher:||Blackwell Publishing (now Wiley-Blackwell)|
|Citation:||Reichstein M, Subke J, Angeli AC & Tenhunen JD (2005) Does the temperature sensitivity of decomposition of soil organic matter depend upon water content, soil horizon, or incubation time?, Global Change Biology, 11 (10), pp. 1754- 1767.|
|Abstract:||Several studies have shown multiple confounding factors influencing soil respiration in the field, which often hampers a correct separation and interpretation of the different environmental effects on respiration. Here, we present a controlled laboratory experiment on undisturbed organic and mineral soil cores separating the effects of temperature, drying–rewetting and decomposition dynamics on soil respiration. Specifically, we address the following questions: (1) Is the temperature sensitivity of soil respiration (Q10) dependent on soil moisture or soil organic matter age (incubation time) and does it differ for organic and mineral soil as suggested by recent field studies. (2) How much do organic and mineral soil layers contribute to total soil respiration? (3) Is there potential to improve soil flux models of soil introducing a multilayer source model for soil respiration? Eight organic soil and eight mineral soil cores were taken from a Norway spruce (Picea abies) stand in southern Germany, and incubated for 90 days in a climate chamber with a diurnal temperature regime between 7 and 23 1C. Half of the samples were rewetted daily, while the other half were left to dry and rewetted thereafter. Soil respiration was measured with a continuously operating open dynamic soil respiration chamber system. The Q10 was stable at around 2.7, independent of soil horizon and incubation time, decreasing only slightly when the soil dried. We suggest that recent findings of the Q10 dependency on several factors are emergent properties at the ecosystem level, that should be analysed further e.g. with regard to rhizosphere effects. Most of the soil CO2 efflux was released from the organic samples. Initially, it averaged 4.0 lmolm 2 s 1 and declined to 1.8 lmolm 2 s 1 at the end of the experiment. In terms of the third question, we show that models using only one temperature as predictor of soil respiration fail to explain more than 80% of the diurnal variability, are biased with a hysteresis effect, and slightly underestimate the temperature sensitivity of respiration. In contrast, consistently more than 95% of the diurnal variability is explained by a dual-source model, with one CO2 source related to the surface temperature and another CO2 source related to the central temperature, highlighting the role of soil surface processes for ecosystem carbon balanc|
|Rights:||The publisher does not allow this work to be made publicly available in this Repository. Please use the Request a Copy feature at the foot of the Repository record to request a copy directly from the author; you can only request a copy if you wish to use this work for your own research or private study.|
|Affiliation:||University of Tuscia|
Biological and Environmental Sciences
University of York
University of Bayreuth
|Reichstein et al 2005_GCB.pdf||548.95 kB||Adobe PDF||Under Embargo until 31/12/2999 Request a copy|
Note: If any of the files in this item are currently embargoed, you can request a copy directly from the author by clicking the padlock icon above. However, this facility is dependant on the depositor still being contactable at their original email address.
This item is protected by original copyright
Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
If you believe that any material held in STORRE infringes copyright, please contact email@example.com providing details and we will remove the Work from public display in STORRE and investigate your claim.