Respiration from oxygen consumption: Difference between revisions
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{{BreadcrumbsSecondaryProduction}} | |||
* [[Page authors|Page authors]]: [[PRIMO]] | |||
* [[Responsible curator|Responsible curator]]: [[User:Hagi BucknWise|Hagen Buck-Wiese]] | |||
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__TOC__ | |||
<div class="model-box"> | |||
{| class="model-ib" style="float:right; margin-left:1em; margin-bottom:1em;" | |||
! Community respiration | |||
|- | |||
| '''Approach:''' O<sub>2</sub> consumption in dark incubations | |||
|- | |||
| '''Context:''' incubation, lab; ''in situ'' | |||
|- | |||
| '''Spatial scale:''' point sample | |||
|- | |||
| '''Temporal scale:''' hours to days | |||
|- | |||
| '''Units:''' µmol O<sub>2</sub> L<sup>-1</sup> h<sup>-1</sup> | |||
|- | |||
| '''Community captured:''' bulk | |||
|- | |||
| '''Co-measurements:''' initial and final O<sub>2</sub>, temperature, volume, incubation time | |||
|} | |||
</div> | |||
<div style="clear:both"></div> | |||
== Method Overview == | |||
Community respiration is measured by tracking the decrease in dissolved oxygen concentration in sealed, dark-incubated water samples. Two main analytical approaches are used: end-point assessment by Winkler titration, in which oxygen is fixed chemically at the start and end of the incubation and quantified by iodometric titration<ref name="Carpenter1965">Carpenter, J. H. (1965). The Chesapeake Bay Institute technique for the Winkler dissolved oxygen method. ''Limnology and Oceanography'', 10(1), 141–143. https://doi.org/10.4319/lo.1965.10.1.0141</ref>; and continuous measurement using optical oxygen sensors (optodes), which allow real-time tracking of O<sub>2</sub> dynamics throughout the incubation<ref name="Warkentin2007">Warkentin, M., Freese, H. M., Karsten, U., & Schumann, R. (2007). New and fast method to quantify respiration rates of bacterial and plankton communities in freshwater ecosystems by using optical oxygen sensor spots. ''Applied and Environmental Microbiology'', 73(21), 6722–6729. https://doi.org/10.1128/AEM.00405-07</ref>. | |||
Incubations can be performed on board (''in vitro'') or deployed ''in situ'' using purpose-built incubators such as RESPIRE<ref name="Boyd2015">Boyd, P. W., McDonnell, A., Valdez, J., LeFevre, D., & Gall, M. P. (2015). RESPIRE: An ''in situ'' particle interceptor to conduct particle remineralization and microbial dynamics studies in the oceans' twilight zone. ''Limnology and Oceanography: Methods'', 13(9), 494–508. https://doi.org/10.1002/lom3.10043</ref>. The change in oxygen concentration over the incubation period, normalized to volume and time, gives the community respiration rate. | |||
=== Scale of measurement === | |||
Each incubation provides a point measurement in space. Multiple incubations across a depth profile or transect are typically combined to characterize spatial patterns. Temporal resolution is set by the incubation duration, which ranges from a few hours (optode-based) to 24 h (Winkler endpoint). | |||
=== Data generated === | |||
The method yields bulk community respiration rate in µmol O<sub>2</sub> L<sup>-1</sup> h<sup>-1</sup>, reflecting the combined metabolic activity of all organisms in the incubation. This integrates bacterial, microeukaryote, and (if present) zooplankton respiration. | |||
=== Units & currency === | |||
Units are µmol O<sub>2</sub> L<sup>-1</sup> h<sup>-1</sup>. The currency is oxygen; conversion to carbon requires a respiratory quotient (RQ), typically assumed to be ~0.8 but variable with substrate composition. | |||
=== Sample size === | |||
Winkler titrations commonly use 125–300 mL BOD bottles. | |||
=== Repositories & databases === | |||
== Limitations == | |||
The method assumes that respiration in the dark equals respiration in the light, and that community composition and activity remain stable throughout the incubation. Bottle confinement can alter trophic interactions and the physico-chemical environment relative to ambient conditions. For optode-based continuous measurements, sensor drift and biofouling over longer incubations must be monitored. Conversion to carbon units is uncertain due to variability in RQ across different microbial substrates and communities. | |||
== Example Applications & Protocols == | |||
=== Classic examples === | |||
* Carpenter (1965) ''The Chesapeake Bay Institute technique for the Winkler dissolved oxygen method'' <ref name="Carpenter1965" /> | |||
* Warkentin et al. (2007) ''New and fast method to quantify respiration rates of bacterial and plankton communities by using optical oxygen sensor spots'' <ref name="Warkentin2007" /> | |||
* Boyd et al. (2015) ''RESPIRE: An in situ particle interceptor for particle remineralization and microbial dynamics studies'' <ref name="Boyd2015" /> | |||
=== Recent applications === | |||
* | |||
=== Common calculations/conversions === | |||
* Respiration rate (µmol O<sub>2</sub> L<sup>-1</sup> h<sup>-1</sup>) = (O<sub>2,initial</sub> − O<sub>2,final</sub>) / incubation time. | |||
* Carbon respiration = O<sub>2</sub> consumption / RQ; a community RQ of 0.8 is commonly assumed for mixed marine communities. | |||
== References == | |||
[[Category:Main Pages|Model types]] | |||
Latest revision as of 15:02, 11 May 2026
Template:BreadcrumbsSecondaryProduction
| Community respiration |
|---|
| Approach: O2 consumption in dark incubations |
| Context: incubation, lab; in situ |
| Spatial scale: point sample |
| Temporal scale: hours to days |
| Units: µmol O2 L-1 h-1 |
| Community captured: bulk |
| Co-measurements: initial and final O2, temperature, volume, incubation time |
Method Overview
Community respiration is measured by tracking the decrease in dissolved oxygen concentration in sealed, dark-incubated water samples. Two main analytical approaches are used: end-point assessment by Winkler titration, in which oxygen is fixed chemically at the start and end of the incubation and quantified by iodometric titration[1]; and continuous measurement using optical oxygen sensors (optodes), which allow real-time tracking of O2 dynamics throughout the incubation[2].
Incubations can be performed on board (in vitro) or deployed in situ using purpose-built incubators such as RESPIRE[3]. The change in oxygen concentration over the incubation period, normalized to volume and time, gives the community respiration rate.
Scale of measurement
Each incubation provides a point measurement in space. Multiple incubations across a depth profile or transect are typically combined to characterize spatial patterns. Temporal resolution is set by the incubation duration, which ranges from a few hours (optode-based) to 24 h (Winkler endpoint).
Data generated
The method yields bulk community respiration rate in µmol O2 L-1 h-1, reflecting the combined metabolic activity of all organisms in the incubation. This integrates bacterial, microeukaryote, and (if present) zooplankton respiration.
Units & currency
Units are µmol O2 L-1 h-1. The currency is oxygen; conversion to carbon requires a respiratory quotient (RQ), typically assumed to be ~0.8 but variable with substrate composition.
Sample size
Winkler titrations commonly use 125–300 mL BOD bottles.
Repositories & databases
Limitations
The method assumes that respiration in the dark equals respiration in the light, and that community composition and activity remain stable throughout the incubation. Bottle confinement can alter trophic interactions and the physico-chemical environment relative to ambient conditions. For optode-based continuous measurements, sensor drift and biofouling over longer incubations must be monitored. Conversion to carbon units is uncertain due to variability in RQ across different microbial substrates and communities.
Example Applications & Protocols
Classic examples
- Carpenter (1965) The Chesapeake Bay Institute technique for the Winkler dissolved oxygen method [1]
- Warkentin et al. (2007) New and fast method to quantify respiration rates of bacterial and plankton communities by using optical oxygen sensor spots [2]
- Boyd et al. (2015) RESPIRE: An in situ particle interceptor for particle remineralization and microbial dynamics studies [3]
Recent applications
Common calculations/conversions
- Respiration rate (µmol O2 L-1 h-1) = (O2,initial − O2,final) / incubation time.
- Carbon respiration = O2 consumption / RQ; a community RQ of 0.8 is commonly assumed for mixed marine communities.
References
- ↑ 1.0 1.1 Carpenter, J. H. (1965). The Chesapeake Bay Institute technique for the Winkler dissolved oxygen method. Limnology and Oceanography, 10(1), 141–143. https://doi.org/10.4319/lo.1965.10.1.0141
- ↑ 2.0 2.1 Warkentin, M., Freese, H. M., Karsten, U., & Schumann, R. (2007). New and fast method to quantify respiration rates of bacterial and plankton communities in freshwater ecosystems by using optical oxygen sensor spots. Applied and Environmental Microbiology, 73(21), 6722–6729. https://doi.org/10.1128/AEM.00405-07
- ↑ 3.0 3.1 Boyd, P. W., McDonnell, A., Valdez, J., LeFevre, D., & Gall, M. P. (2015). RESPIRE: An in situ particle interceptor to conduct particle remineralization and microbial dynamics studies in the oceans' twilight zone. Limnology and Oceanography: Methods, 13(9), 494–508. https://doi.org/10.1002/lom3.10043