Wildrosenweg 3 · D-24119 Kiel-Kronshagen Phone (+49) 431 38040-0 Fax (+49) 431 38040-10 E-mail info@bbe-moldaenke.de Web www.bbe-moldaenke.de The bbe BenthoFluor A portable fluorometer to analyse benthic algae Various algal species have adapted different algal pigments. their nutrient uptake systems enabling By measuring the amount of red light them to survive in shallow water close to fluorescence, arising from illumination the shoreline, where sunlight still at different excitation wavelengths, a penetrates to the sea bed. This habitat is quantitative estimate of algal density and home to benthic algae, ranging from the its distribution between the different microscopic to the enormous (Giant classes is now possible. This technique Kelp). Such flora, attached to the has been well proven for pelagic seafloor sediments, play an essential phytoplankton, by extensive application role in primary production. of the bbe submersible FluoroProbe, and has now successfully been adapted to In December 2000, the European measure benthic algae. Water Framework Directive (EU-WFD) came into force. This directive stipulates The BenthoFluor is housed in a water that the ecological status of water resistant, carbon-fibre reinforced case masses must be assessed. In order to do so, several biological elements must be considered, including benthic algae. As a result, it has become obligatory to bbe BenthoFluor in field research study the development and abundance Foto by R. Dörffer, AWI Bremerhaven of benthic communities. The collected data will satisfactorily contribute to the assessment of the water quality in and during use, is transported in a back-aquatic ecosystems. pack or placed inside a small boat. All the electronics, data processing and storage Whilst macroscopic algae can be are confined in the unit, with the light easily observed due to their size, the irradiation and subsequent fluorescence occurrence of the microscopic benthic being transmitted along a 1.5m fibre-optic algae are difficult to record. The cable to a submersible adaptor. This necessity for time-consuming micro-adaptor ensures a constant distance scopy has hindered effective analysis of between the sediment and the fibre-optics, benthic algal groups. Now, using the excludes ambient light enabling dark new bbe BenthoFluor, it is possible to adaptation and prevents disturbance of the analyse benthic algae in-situ, by utilising sediment layers. The unit is controlled by a the fluorometric characteristics of the Fiber optics with adaption disk laptop or small handheld PC (Archer PDA). The chlorophyll-a content is displayed in real time in the measuring range up to 2 3 µg/cm . Up to three algae classes are determined simultaneously. All data are recorded on the display or stored in the datalogger of the BenthoFluor for further analysis. The ability to obtain and evaluate the results of the measurement on site makes the BenthoFluor a valuable tool in benthic algae analysis. The BenthoFluor comes with bbe software for use with Windows. The software uses spectral fingerprints of standardised algae from laboratory cultures but also allows the user to introduce his or her own type of algae as a special class. The BenthoFluor is a versatile instrument. Removal of the holder with fibre-optics quickly converts the BenthoFluor into a submersible FluoroProbe. Installation of the parameter set for FluoroProbe operations Distribution of benthic algae: horizontal transect in the requires only a PC and the standard bbe tidelands of North Sea near Westerhever FluoroProbe software. The graph shows the presence of diatoms. Principle of the Instrument Technical Data 2 Measuring range 0 -3 µg chl-a/cm 2 Resolution 0.1 µg chl-a/cm Flu Algae classes Up to 3 6 o 8 re Weight kg 5 s n c m e Voltage 12V n LEDs ce Operation time / load >10h Data capacity 1800 data sets High Pass Beam Band Pass Serial interface RS232 Divider (98% reflection) Housing IP 56 Your local bbe dealer... Mirror High Pass Brightness Sample © bbe Moldaenke GmbH 2003 Document Outline Seite1 Seite2