Publication Date:
2009-12-17
Description:
Biota can be described in terms of elemental composition, expressed as an atomic ratio of carbon:nitrogen:phosphorus (refs 1-3). The elemental stoichiometry of microoorganisms is fundamental for understanding the production dynamics and biogeochemical cycles of ecosystems because microbial biomass is the trophic base of detrital food webs. Here we show that heterotrophic microbial communities of diverse composition from terrestrial soils and freshwater sediments share a common functional stoichiometry in relation to organic nutrient acquisition. The activities of four enzymes that catalyse the hydrolysis of assimilable products from the principal environmental sources of C, N and P show similar scaling relationships over several orders of magnitude, with a mean ratio for C:N:P activities near 1:1:1 in all habitats. We suggest that these ecoenzymatic ratios reflect the equilibria between the elemental composition of microbial biomass and detrital organic matter and the efficiencies of microbial nutrient assimilation and growth. Because ecoenzymatic activities intersect the stoichiometric and metabolic theories of ecology, they provide a functional measure of the threshold at which control of community metabolism shifts from nutrient to energy flow.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sinsabaugh, Robert L -- Hill, Brian H -- Follstad Shah, Jennifer J -- England -- Nature. 2009 Dec 10;462(7274):795-8. doi: 10.1038/nature08632.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Biology Department, University of New Mexico, Albuquerque, New Mexico 871312, USA. rlsinsab@unm.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20010687" target="_blank"〉PubMed〈/a〉
Keywords:
Biomass
;
Carbon/*metabolism
;
*Ecosystem
;
Enzyme Assays
;
Enzymes/*metabolism
;
Food Chain
;
Geologic Sediments/*chemistry/microbiology
;
Nitrogen/*metabolism
;
Phosphorus/*metabolism
;
Plants/metabolism
;
Rivers
;
*Soil Microbiology
;
United States
;
Wetlands
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
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