Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1002/jpln.200700051
Title (Primary) Soil carbon preservation through habitat constraints and biological limitations on decomposer activity
Author Ekschmitt, K.; Kandeler, E.; Poll, C.; Brune, A.; Buscot, F.; Friedrich, M.; Gleixner, G.; Hartmann, A.; Kästner, M.; Marhan, S.; Miltner, A. ORCID logo ; Scheu, S.; Wolters, V.
Source Titel Journal of Plant Nutrition and Soil Science
Year 2008
Department UBT; BOOEK
Volume 171
Issue 1
Page From 27
Page To 35
Language englisch
Keywords soil microflora; soil fauna; carbon turnover; recalcitrance; accessibility
Abstract We review recent experimental results on the role of soil biota in stabilizing or destabilizing soil organic matter (SOM). Specifically, we analyze how the differential substrate utilization of the various decomposer organisms contributes to a decorrelation of chemical stability, residence time, and carbon (C) age of organic substrates. Along soil depth profiles, a mismatch of C allocation and abundance of decomposer organisms is consistently observed, revealing that a relevant proportion of soil C is not subjected to efficient decomposition. Results from recent field and laboratory experiments suggest that (1) bacterial utilization of labile carbon compounds is limited by short-distance transport processes and, therefore, can take place deep in the soil under conditions of effective local diffusion or convection. In contrast, (2) fungal utilization of phenolic substrates, including lignin, appears to be restricted to the upper soil layer due to the requirement for oxygen of the enzymatic reaction involved. (3) Carbon of any age is utilized by soil microorganisms, and microbial C is recycled in the microbial food web. Due to stoichiometric requirements of their metabolism, (4) soil animals tend to reduce the C concentration of SOM disproportionally, until it reaches a threshold level. The reviewed investigations provide new and quantitative evidence that different soil C pools underlie divergent biological constraints of decomposition. The specialization of decomposers towards different substrates and microhabitats leads to a relatively longer persistence of virtually all kinds of organic substrates in the nonpreferred soil spaces. We therefore propose to direct future research explicitly towards such biologically nonpreferred areas where decomposition rates are slow, or where decomposition is frequently interrupted, in order to assess the potential for long-term preservation of C in the soil.
Persistent UFZ Identifier
Ekschmitt, K., Kandeler, E., Poll, C., Brune, A., Buscot, F., Friedrich, M., Gleixner, G., Hartmann, A., Kästner, M., Marhan, S., Miltner, A., Scheu, S., Wolters, V. (2008):
Soil carbon preservation through habitat constraints and biological limitations on decomposer activity
J. Plant Nutr. Soil Sci. 171 (1), 27 - 35 10.1002/jpln.200700051