The predecessor of the DIVING-PAM-II (the DIVING-PAM) has been proven as reliable and robust chlorophyll fluorometer for studying photosynthesis in and under water. To date, about 500 scientific papers containing measurements with the DIVING-PAM have been published.
The DIVING-PAM-II continues the proven and trusted design of its predecessor but advances data acquisition and instrument control by employing the latest progress in LED technology, optics and electronics.
DIVING-PAM-II and Universal Sample Holder DIVING-II-USH
The DIVING-PAM-II fluorometer permits examinations of photosynthesis down to 50 m water depth. All functions of the instrument can be controlled by 10 infrared reflection switches situated inside a transparent, cylinder-shaped housing. A new feature is the energy-saving B/W screen which displays instrument status and measured data. The transflective screen is readable even under sunlight. For long-term assessment of photosynthesis, the instrument can also be operated by a computer via a special underwater cable.
The innovative Miniature Spectrometer MINI-SPEC, being part of the basic DIVING-PAM-II system, adds a new level of information to studies of photosynthesis. The MINI-SPEC measures spectra of PAR, which are known to vary significantly with water depth. The device also permits spectral analyses of reflectance and fluorescence emission of a sample. Also new is an internal PAR sensor which continuously records the intensity of the internal light source of the DIVING-PAM-II.
In situ investigations of cyanobacterial photosynthesis using a Walz DIVING-PAM fluorometer has been released. The video was recorded during a research campaign in Greenland (2013) which was targeted to photosynthesis of algae on surfaces of submarine mineral formations (ikaide columns). This research campaign was sponsored in part by Walz.
Miniature spectrometer for PAR measurement, spectral information on PAR and reflectance
Wireless LAN for convenient data download at experimental site
Graphical and alphanumerical display by low-power consuming transflective B/W screen
High power LED for actinic light and saturation pulses. Far red LED for PS I excitation.
Advanced pressure and temperature sensor
High capacity battery for more than 1,300 PS II yield measurements. Flash memory for more than 27,000 saturation pulse analyses
Continuous monitoring of internal light intensity by built-in PAR sensor
Automatic calculation of all relevant parameters of saturation pulse analysis
Accessories included in the basic system:
1.5 m flexible fiber optics, miniature spectrometer, distance clip, dark leaf clips, surface holder, PC Interface Box, battery charger, USB cable, 5 m underwater cable, WinControl-3 software packed in a rugged outdoor transport case
The color of light emitted by the primary LED distinguishes the BLUE from the RED version of the DIVING-PAM-II fluorometer (Fig. 1). The BLUE version (DIVING-PAM-II/B) possesses a blue LED emitting maximally around 475 nm which is replaced by a red LED emitting maximally around 655 nm in the RED version (DIVING-PAM-II/R). Both versions have a second LED providing far red light for specific excitation of photosystem I.
The second difference between the two versions is the spectral window for fluorescence detection. The BLUE version detects fluorescence at wavelengths > 630 nm but the RED version detects fluorescence at wavelengths > 700 nm (Fig. 2).
Figure 1: Typical LED emission spectra normalized to their maxima. The blue curve corresponds to the spectrum of the blue LED of the DIVING-PAM-II/B, the orange curve represents the red LED in the DIVING-PAM-II/R. Both DIVING-PAM-II versions possess a far red LED which emits maximally above 700 nm (rightmost curve). Max, peak wavelength in nm. FWHM, full width at half maximum in nm.