Microbial carbon limitation: The need for integrating microorganisms into our understanding of ecosystem carbon cycling

Journal Article · Sat Jan 25 00:00:00 EST 2020 · Global Change Biology

DOI:https://doi.org/10.1111/gcb.14962· OSTI ID:1595151

Soong, Jennifer L.  ^[1]; Fuchslueger, Lucia  ^[2]; Marañon‐Jimenez, Sara  ^[3]; Torn, Margaret S.  ^[1]; Janssens, Ivan A.  ^[4]; Penuelas, Josep  ^[3]; Richter, Andreas  ^[5]

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1. Lawrence Berkeley National Laboratory Climate and Ecosystem Science Division Berkeley CA USA
2. Department of Biology University of Antwerp Wilrijk Belgium, Centre for Microbiology and Environmental Systems Science University of Vienna Vienna Austria
3. Center for Ecological Research and Forestry Application Bellaterra Catalonia Spain, Global Ecology Unit CREAF‐CSIC‐UAB Bellaterra Catalonia Spain
4. Department of Biology University of Antwerp Wilrijk Belgium
5. Centre for Microbiology and Environmental Systems Science University of Vienna Vienna Austria, Ecosystems Services and Management Program International Institute for Applied Systems Analysis Laxenburg Austria

Abstract Numerous studies have demonstrated that fertilization with nutrients such as nitrogen, phosphorus, and potassium increases plant productivity in both natural and managed ecosystems, demonstrating that primary productivity is nutrient limited in most terrestrial ecosystems. In contrast, it has been demonstrated that heterotrophic microbial communities in soil are primarily limited by organic carbon or energy. While this concept of contrasting limitations, that is, microbial carbon and plant nutrient limitation, is based on strong evidence that we review in this paper, it is often ignored in discussions of ecosystem response to global environment changes. The plant‐centric perspective has equated plant nutrient limitations with those of whole ecosystems, thereby ignoring the important role of the heterotrophs responsible for soil decomposition in driving ecosystem carbon storage. To truly integrate carbon and nutrient cycles in ecosystem science, we must account for the fact that while plant productivity may be nutrient limited, the secondary productivity by heterotrophic communities is inherently carbon limited. Ecosystem carbon cycling integrates the independent physiological responses of its individual components, as well as tightly coupled exchanges between autotrophs and heterotrophs. To the extent that the interacting autotrophic and heterotrophic processes are controlled by organisms that are limited by nutrient versus carbon accessibility, respectively, we propose that ecosystems by definition cannot be ‘limited’ by nutrients or carbon alone. Here, we outline how models aimed at predicting non‐steady state ecosystem responses over time can benefit from dissecting ecosystems into the organismal components and their inherent limitations to better represent plant–microbe interactions in coupled carbon and nutrient models.

• Sponsoring Organization: USDOE
• Grant/Contract Number: DE‐AD01‐05CH11231
• OSTI ID: 1595151
• Journal Information: Global Change Biology, Journal Name: Global Change Biology Vol. 26 Journal Issue: 4; ISSN 1354-1013
• Publisher: Wiley-Blackwell
• Country of Publication: United Kingdom
• Language: English