Carbon use efficiency of microbial communities: stoichiometry, methodology and modelling. (30th April 2013)

• Record Type: Journal Article
• Authors: Sinsabaugh, Robert L.; Manzoni, Stefano; Moorhead, Daryl L.; Richter, Andreas; Elser, James
• Is Part Of: Ecology letters. Volume 16:Number 7(2013:Jul.)
• Page Start: 930
• Page End: 939
• Publication Date: 2013-04-30
• Subjects: Ecology -- Periodicals; 577
• DOI: 10.1111/ele.12113
• Languages: English
• ISSNs: 1461-023X

Abstract

<abstract abstract-type="main" id="ele12113-abs-0001"> <title>Abstract</title> <p>Carbon use efficiency (CUE) is a fundamental parameter for ecological models based on the physiology of microorganisms. CUE determines energy and material flows to higher trophic levels, conversion of plant‐produced carbon into microbial products and rates of ecosystem carbon storage. Thermodynamic calculations support a maximum CUE value of ~ 0.60 (CUE <sub>max</sub>). Kinetic and stoichiometric constraints on microbial growth suggest that CUE in multi‐resource limited natural systems should approach ~ 0.3 (CUE <sub>max</sub>/2). However, the mean CUE values reported for aquatic and terrestrial ecosystems differ by twofold (~ 0.26 vs. ~ 0.55) because the methods used to estimate CUE in aquatic and terrestrial systems generally differ and soil estimates are less likely to capture the full maintenance costs of community metabolism given the difficulty of measurements in water‐limited environments. Moreover, many simulation models lack adequate representation of energy spilling pathways and stoichiometric constraints on metabolism, which can also lead to overestimates of CUE. We recommend that broad‐scale models use a CUE value of 0.30, unless there is evidence for lower values as a result of pervasive nutrient limitations. Ecosystem models operating at finer scales should consider resource composition, stoichiometric constraints and biomass composition, as well as environmental drivers, to predict the CUE of microbial communities.</p> </abstract>