Abstract: An apparatus employs a plurality of transducers distributed along a cable to sample a medium. Some of the transducers may be operated according to various sequences which specific wavelengths and/or magnitudes of emission of electromagnetic energy. Some of the transducers sample, detect or measure responses of the fluid medium to the emissions. Various other transducers may sample or measure temperature, depth or pressure, and flow characteristics of the fluid medium, and optionally flow characteristics above a surface or above a surface of the fluid medium. Such may allow identification and/or characterization of characteristics of the fluid medium and/or substances (e.g., contaminants for instance petroleum, phytoplankton, red tide microorganisms, nutrients, dissolved oxygen or other gasses). The apparatus may communicate with remote facilities, allowing monitoring, remote control, and/or analysis with or with information from other platforms.