Bacterial Growth Efficiency in Natural Aquatic Systems

Giorgio, Paul A. del; Cole, Jonathan J.

doi:10.1146/annurev.ecolsys.29.1.503

Cited by 1,202 publications

(1,031 citation statements)

References 150 publications

(197 reference statements)

Supporting

Mentioning

923

Contrasting

Unclassified

Order By: Relevance

“…Thus, bacteria act as either remineralizers or consumers of ammonium, depending on the relationship between their fixed C:N ratio and that of the DOM they consume. Bacterial growth efficiency was set at 0.30 to reflect measured estuarine growth efficiencies (del Giorgio and Cole, 1998).…”

Section: Bacteriamentioning

confidence: 99%

Modeling the seasonal autochthonous sources of dissolved organic carbon and nitrogen in the upper Chesapeake Bay

Keller

Hood

2011

Ecological Modelling

View full text Add to dashboard Cite

a b s t r a c tIn this paper we investigate the seasonal autochthonous sources of dissolved organic carbon (DOC) and nitrogen (DON) in the euphotic zone at a station in the upper Chesapeake Bay using a new mass-based ecosystem model. Important features of the model are: (1) carbon and nitrogen are incorporated by means of a set of fixed and varying C:N ratios; (2) dissolved organic matter (DOM) is separated into labile, semi-labile, and refractory pools for both C and N; (3) the production and consumption of DOM is treated in detail; and (4) seasonal observations of light, temperature, nutrients, and surface layer circulation are used to physically force the model. The model reasonably reproduces the mean observed seasonal concentrations of nutrients, DOM, plankton biomass, and chlorophyll a. The results suggest that estuarine DOM production is intricately tied to the biomass concentration, ratio, and productivity of phytoplankton, zooplankton, viruses, and bacteria. During peak spring productivity phytoplankton exudation and zooplankton sloppy feeding are the most important autochthonous sources of DOM. In the summer when productivity peaks again, autochthonous sources of DOM are more diverse and, in addition to phytoplankton exudation, important ones include viral lysis and the decay of detritus. The potential importance of viral decay as a source of bioavailable DOM from within the bulk DOM pool is also discussed. The results also highlight the importance of some poorly constrained processes and parameters. Some potential improvements and remedies are suggested. Sensitivity studies on selected parameters are also reported and discussed.

show abstract

Section: Bacteriamentioning

confidence: 99%

Modeling the seasonal autochthonous sources of dissolved organic carbon and nitrogen in the upper Chesapeake Bay

Keller

Hood

2011

Ecological Modelling

View full text Add to dashboard Cite

show abstract

“…Two empirical equations have largely been used, one estimating BGE from bacterial production (del Giorgio & Cole 1998) and the other from temperature (Rivkin & Legendre 2001). However, they all have high data scatter and low predictive capabilities since BGE seems to depend on all these parameters simultaneously (López-Urrutia & Morán 2007).…”

Section: How Accurately Are We Measuring Bacterial Activities?mentioning

confidence: 99%

“…However, they all have high data scatter and low predictive capabilities since BGE seems to depend on all these parameters simultaneously (López-Urrutia & Morán 2007). The review of del Giorgio & Cole (1998), however, made clear that the previously often used BGEs of > 30% are too high for the oligotrophic surface ocean.…”

Section: How Accurately Are We Measuring Bacterial Activities?mentioning

confidence: 99%

Towards a better understanding of microbial carbon flux in the sea*

Gasol¹,

Pinhassi²,

Alonso‐Sáez³

et al. 2008

Aquat. Microb. Ecol.

View full text Add to dashboard Cite

We now have a relatively good idea of how bulk microbial processes shape the cycling of organic matter and nutrients in the sea. The advent of the molecular biology era in microbial ecology has resulted in advanced knowledge about the diversity of marine microorganisms, suggesting that we might have reached a high level of understanding of carbon fluxes in the oceans. However, it is becoming increasingly clear that there are large gaps in the understanding of the role of bacteria in regulating carbon fluxes. These gaps may result from methodological as well as conceptual limitations. For example, should bacterial production be measured in the light? Can bacterial production conversion factors be predicted, and how are they affected by loss of tracers through respiration? Is it true that respiration is relatively constant compared to production? How can accurate measures of bacterial growth efficiency be obtained? In this paper, we discuss whether such questions could (or should) be addressed. Ongoing genome analyses are rapidly widening our understanding of possible metabolic pathways and cellular adaptations used by marine bacteria in their quest for resources and struggle for survival (e.g. utilization of light, acquisition of nutrients, predator avoidance, etc.). Further, analyses of the identity of bacteria using molecular markers (e.g. subgroups of Bacteria and Archaea) combined with activity tracers might bring knowledge to a higher level. Since bacterial growth (and thereby consumption of DOC and inorganic nutrients) is likely regulated differently in different bacteria, it will be critical to learn about the life strategies of the key bacterial species to achieve a comprehensive understanding of bacterial regulation of C fluxes. Finally, some processes known to occur in the microbial food web are hardly ever characterized and are not represented in current food web models. We discuss these issues and offer specific comments and advice for future research agendas.

show abstract

“…This relationship between anabolic and catabolic activity is often represented in terms of carbon use efficiency (CUE), a measure of the proportion of the utilized carbon source that is converted into microbial biomass (del Giorgio and Cole 1998;Winzler and Baumberger 1938). Changes in the CUE of saprotrophic microorganisms in response to increases in temperature could potentially have large effects on overall terrestrial soil CO 2 emissions.…”

Section: Introductionmentioning

confidence: 99%

The effect of temperature and substrate quality on the carbon use efficiency of saprotrophic decomposition

et al. 2016

View full text Add to dashboard Cite

Background and aims Mineralization of soil organic matter (SOM) constitutes a major carbon flux to the atmosphere. The carbon use efficiency (CUE) of the saprotrophic microorganisms mineralizing SOM is integral for soil carbon dynamics. Here we investigate how the CUE is affected by temperature, metabolic conditions, and the molecular complexity of the substrate. Methods We incubated O-horizon soil samples (with either 13 C-glucose or 13 C-cellulose) from a boreal coniferous forest at 4, 9, 14, and 19°C, and calculated CUEs based on the amount of 13 C-CO 2 and 13 C-labelled microbial biomass produced. The effects of substrate, temperature, and metabolic conditions (representing unlimited substrate supply and substrate limitation) on CUE were evaluated. Results CUE from metabolizing glucose was higher as compared to cellulose. A slight decrease in CUE with increasing temperature was observed in glucose amended samples (but only in the range 9-19°C), but not in cellulose amended samples. CUE differed significantly with metabolic conditions, i.e. CUE was higher during unlimited growth conditions as compared to conditions with substrate limitation. Conclusions We conclude that it is integral to account for both differences in CUE during different metabolic phases, as well as complexity of substrate, when interpreting temperature dependence on CUE in incubation studies.

show abstract

Bacterial Growth Efficiency in Natural Aquatic Systems

Cited by 1,202 publications

References 150 publications

Modeling the seasonal autochthonous sources of dissolved organic carbon and nitrogen in the upper Chesapeake Bay

Modeling the seasonal autochthonous sources of dissolved organic carbon and nitrogen in the upper Chesapeake Bay

Towards a better understanding of microbial carbon flux in the sea*

The effect of temperature and substrate quality on the carbon use efficiency of saprotrophic decomposition

Contact Info

Product

Resources

About