Hagi BucknWise at 23:10, 11 May 2026

2026-05-11T23:10:01Z

← Older revision		Revision as of 16:10, 11 May 2026
Line 3:		Line 3:
	* [[Page authors\|Page authors]]: [[PRIMO]]		* [[Page authors\|Page authors]]: [[PRIMO]]
	* [[Responsible curator\|Responsible curator]]: [[User:Hagi BucknWise\|Hagen Buck-Wiese]]		* [[Responsible curator\|Responsible curator]]: [[User:Hagi BucknWise\|Hagen Buck-Wiese]]

			IS THIS ENTRY IN THE CORRECT SECTION? I THINK NOT
	----		----

Hagi BucknWise: Created page with "{{BreadcrumbsPrimaryProduction}} * Page authors: PRIMO * Responsible curator: Hagen Buck-Wiese ---- TOC
{| class="model-ib" style="float:right; margin-left:1em; margin-bottom:1em;" ! O₂ optode method |- | '''Approach:''' continuous O₂ measurement by luminescent optode, light and dark bottles |- | '''Context:''' incubation, simulated ''in situ'' |- | '..."

2026-05-11T23:08:53Z

Created page with "{{BreadcrumbsPrimaryProduction}} * Page authors: PRIMO * Responsible curator: Hagen Buck-Wiese ---- __TOC__ <div class="model-box"> {| class="model-ib" style="float:right; margin-left:1em; margin-bottom:1em;" ! O2 optode method |- | '''Approach:''' continuous O2 measurement by luminescent optode, light and dark bottles |- | '''Context:''' incubation, simulated ''in situ'' |- | '..."

New page

{{BreadcrumbsPrimaryProduction}}

* [[Page authors|Page authors]]: [[PRIMO]]
* [[Responsible curator|Responsible curator]]: [[User:Hagi BucknWise|Hagen Buck-Wiese]]
----

__TOC__
<div class="model-box">
{| class="model-ib" style="float:right; margin-left:1em; margin-bottom:1em;"
! O2 optode method
|-
| '''Approach:''' continuous O2 measurement by luminescent optode, light and dark bottles
|-
| '''Context:''' incubation, simulated ''in situ''
|-
| '''Spatial scale:''' point sample
|-
| '''Temporal scale:''' hours to one day
|-
| '''Units:''' µmol O2 L-1 d-1; convertible to µmol C L-1 d-1
|-
| '''Community captured:''' all
|-
| '''Co-measurements:''' temperature, PAR, salinity, pressure; photosynthetic quotient (PQ) for C conversion
|}
</div>
<div style="clear:both"></div>

== Method Overview ==

Luminescent optical oxygen sensors (optodes) are mounted inside incubation bottles, allowing dissolved O2 to be logged continuously throughout the incubation rather than at a single endpoint. The same light-dark bottle design as the Winkler method is used: light bottles capture NCP (net O2 production); dark bottles capture community respiration (CR). GPP = NCP + CR. Because O2 is measured continuously, the method can resolve short-term dynamics and diel patterns within a single incubation, and non-linear responses in the dark bottles can be detected and accounted for.

Optodes respond to the partial pressure of dissolved O2 via a luminescence lifetime that decreases as O2 quenches a fluorescent dye embedded in the sensor membrane. Temperature and salinity corrections are required for accurate O2 concentration calculations.

=== Scale of measurement ===

As a bottle-based incubation, the method provides a point measurement in space. Larger bottle volumes (> 1 L) compared to Winkler bottles reduce the relative contribution of wall effects and increase the signal-to-noise ratio for low-productivity waters.

=== Data generated ===

The method yields time-resolved O2 concentration trajectories, from which GPP, NCP, and CR are estimated as linear rates over selected time windows. Conversion to carbon requires PQ (for GPP and NCP) and RQ (for CR).

=== Units & currency ===

Units are µmol O2 L-1 d-1, or µmol C L-1 d-1 after conversion. The currency is oxygen (carbon is derived).

=== Sample size ===

Typical samples are > 1 L in volume.

=== Repositories & databases ===

== Limitations ==

Sensor drift over longer incubations must be monitored and corrected. Response times of optodes can lag behind rapidly changing O2 concentrations. Gas permeability of some incubation vessel materials can introduce artefacts in the O2 mass balance. The same biological bottle effects (grazer exclusion, altered physico-chemical environment) apply as in the Winkler method. Light-dependent O2 consumption reactions can cause overestimation of GPP.

== Example Applications & Protocols ==

=== Classic examples ===
*

=== Recent applications ===
*

=== Common calculations/conversions ===
* GPP (µmol O2 L-1 d-1) = rate of O2 increase in light bottle − rate of O2 decrease in dark bottle.
* GPP (µmol C L-1 d-1) = GPPO2 / PQ.

== References ==

[[Category:Main Pages|Model types]]

Continuous dissolved oxygen (DO) optodes - Revision history

Hagi BucknWise at 23:10, 11 May 2026