FastOcean ADP Profiling System
FastOcean APD is an automous profiling system which comprises two FastOcean multi-wavelength Fast Repetition Rate fluorometers (ambient plus dark), pumped dark chamber, programmable battery pack and a PAR sensor for autonomous, in situ estimation of gross primary production. This system is smaller, lighter and more power efficient than earlier FRRf profiling systems.
This high performance system is suitable for use in a wide range of applications from the assessment of primary production within the world's oceans to environmental monitoring within reservoirs and rivers.
- Applications and Features
- In situ estimation of gross primary productivity (GPP): With fully configured FastOcean-based systems
- Sea-truthing of satellite data: Using new algorithms for the estimation of GPP and light absorption
- Incorporates third generation (FRRf3) FastOcean sensors: Which makes the complete systems smaller, lighter, more power efficient and far more capable than earlier FRRf profiling systems
- Real time and battery (autonomous) versions: The real time version uses a sea cable and interface unit to connect to a PC at the surface, whilst the battery version logs data within each FastOcean sensor (including PAR and pressure)
- New data analysis methods: Which remove the requirement for independent measurement of PSII reaction centre concentration for estimation of gross primary productivity and improve signal to noise at high PAR
- Three excitation wavelengths: Independently controlled LED arrays for fluorescence excitation, centred at 450, 530 and 624 nm
- Integration of PAR and pressure: Synchronised PAR and pressure values are logged within the ambient sensor and/or transmitted to the surface with the FRRf data
- Pumped dark chamber: Ensures consistent dark-adaptation and matched sampling between ambient and dark
- FastPro8 GUI: Provides synchronisation between the ambient and dark sensors, whilst providing real time data analysis (real time system) or data import (battery system), analysis, presentation and archiving
- Components & Specifications
System Components Part No Real time system Battery system 1 x FastOcean PTX (2220-140-PL) √ √ 1 x FastOcean to PAR sensor cable (2220-168-PL) √ √
1 x 2pi PAR sensor
(0046-3097-4.3) √ √ 1 x FastOcean (2220-141-PL) √ √ 2 x USB cables (2292-007-PL) √ √ 2 x 24 V power units (2292-008-PL) √ √ 1 x pumped dark chamber (2220-113-PL) √ √ 1 x profiling frame (2220-111-PL) √ √ 1 x profiling frame interconnect cable (2220-167-PL) √ √ 1 x 24 V dual interface unit (2292-003-PL) √ - 1 x programming / deck cable (2220-170-PL) √ - 1 x programmable 24 V battery pack with 3 x remotes (2220-112-PL) - √ 1 x charger for 24 V battery pack (2220-215-PL) - √ 1 x transit case (2220-204-PL) √ √ System Specifications Mass (weight in air, water) 16 kg (157 N, 63 N) 20.3 kg (200 N, 98 N) Dimensions W 316 x D 292 x H 685 mm W 316 x D 292 x H 685 mm Time between charging for battery system - 7 hrs Power consumption for real time system 16 Watts -
- System Integration
Simple Integration of Ambient plus Dark Sensors and Data Within an APD system, the 'primary' FastOcean is the ambient sensor. To add the dark sensor, only the COM port and delay between ambient and dark measurements need to be set, through the FRRf3 APD system dialog. All other settings are automatically matched between sensors by FastPro8. This includes setting the appropriate drive currents for each LED channel to provide the required photon fluxes. FastPro8 provides a number of tools for the presentation of FRRf acquisitions and parameter data. The sample data shown above are generated from the ambient and dark sensors within an APD system, with dark values in brackets, where appropriate. JVPSII values require both ambient and dark, whilst aLHII values are from the dark sensor. FastPro8 includes tools for separating data sets based on excitation levels. In the above example, three datasets could be created on this basis (450 nm, 450 + 530 nm and 450 + 624 nm). The data plot window above can be used to display up to eight parameters simultaneously. If data are from an APD system there is an option to show parameters from both ambient and dark sensors (black line, above). The window above shows matched ambient and dark ST acquisitions. The dark acquisition was taken 2 s after the ambient, to allow for dark-adaptation of the sample. The acquisition showing within this window is linked to the selection within the file and data plot windows shown above.
Parameters available for FastOcean
ST saturation phase data are fit using the equations originally presented by Kolber et al. (1998)1. A full range offluorescence parameters is calculated in real time, including:
Fo 'origin' of variable fluorescence in the dark-adapted state F' steady-state fluorescence in the light-adapted state Fm and Fm' maximum fluorescence in the dark and light-adapted states, respectively Fv/Fm maximum PS II photochemical efficiency Fq'/Fm' PS II operating efficiency RσPSII probability of an RCII being closed by the first ST flashlet σPSII absorption cross section of PSII photochemistry p connectivity parameter [Chl] chlorophyll concentration If an ST measurement includes a relaxation phase, the following additional parameters are calculated in real time: tf time constant for PS II centre re-opening Fa fluorescence at the asymptote of the relaxation phase Parameters available for FastAct & FastOcean APD Systems If a FastOcean sensor is being used with a FastAct system, or two FastOcean sensors are being used in situ as a synchronised pair (light + dark), additional ST saturation phase parameters are calculated in real time, including: Fo' 'origin' of variable fluorescence in the light-adapted state qP, qL and qJ steady-state fluorescence in the light-adapted state NPQ for tracking of Non-Photochemical Quenching JPSII photochemical flux per RCII [RCII] functional RCII centres m-3 JVPSII photochemical flux per unit volume (JPSII m-3) ETR Electronic Transfer Rate (from PSII to NADP)
These data are generated using the established Sigma algorithm plus a new Absorption algorithm (developed in collaboration with researchers at the NOC, Southampton and The University of Essex), which does not require values of σPSII, [RCII] or the fraction of RCII in the open state (from qP, qL or qJ). The Absorption algorithm provides a better signal to noise under high ambient light and low biomass and, in addition, can be used to generate a PSII absorption coefficient (aPSII) with units of m-1.
1Kolber ZS, Prásîl O, Falkowski PG (1998) Measurements of variable chlorophyll fluorescence using fast-repetition rate techniques: defining methodology and experimental protocols Biochim. Biophys. Acta 1367: 88-106.
Fast Repetition Rate Fluorometry in the Press:
Sophie Richier, Anna I. Macey, Nicola J. Pratt, David J. Honey, C. Mark Moore, Thomas S. Bibby, Ocean and Earth Science, National Oceanography Centre. Abundances of Iron-Binding Photosynthetic and Nitrogen-Fixing Proteins of Trichodesmium Both in Culture and In Situ from the North Atlantic. Plus One - 2012. Link to article. Download pdf.
Oxborough, K. Moore, C.M., Suggett, D.J., Lawson, T., Chan, H.G. and Geider, R.G. Direct estimation of functional PSII reaction centre concentration and PSII electron flux on a volume basis: a new approach to the analysis of Fast Repetition Rate fluorometry (FRRf) data. Liminology & Oceanography: Methods – 2012, 10:142-154. Link to article. Download pdf.