Abstract: A wave suppression device, for use suppressing waves and for use in the demarcation of swimming pool lanes, comprised of a cylindrical core having a plurality of fins radially extending from its outer surface. The fins are positioned substantially coextensively along the length of the core. At least one spacer is circumferentially positioned about and connected to the core member and fins. A flotation assembly is axially positioned within the core member and compression fit against the inner surface thereof. The flotation assembly includes a central axial opening for receiving a cable or like device for stringing a plurality of wave suppression devices together to form a lane demarcation.

Abstract: Apparatus is provided for optically measuring scalar irradiance or incident flux of radiant energy and for optically measuring naturally occurring chlorophyll fluorescence or upwelling radiance in a parcel of water in a natural setting. From a comparison of the two measurements, rate of primary photosynthetic production is calculated by appropriately programmed computer means. Readout means are provided to indicate the rate of primary production. Further, concentrations of chlorophyll that generate the primary production are also determined by means of the apparatus of this invention. The method of this invention, employing measurement instruments of the type disclosed, enables the determination of concentrations of chlorophyll and primary production in parcels of water.