Development of a laser spectroscopy method and a hard-software framework for ecological monitoring of underwater areas by remote operated vehicles

The results of the experimental development of the method and the hard-software framework for a remote-operated underwater vehicle are presented in this work. The method of laser induced fluorescence (LIF) and a small-sized laser spectrometer are designed to monitor of the dissolved oil products pollution of underwater areas and to assess the impact of pollution on the phytoplankton community state. The excitation technique of the sea water LIF was experimentally tested to simultaneously measure the concentration of chlorophyll A, the specific reproduction of dissolved organic matter by phytoplankton cells, and the concentration of oil products dissolved in sea water. It has been experimentally shown that to implement this technique, it is necessary to carry out the excitation of the LIF by two wavelength radiation. To measure the concentration of chlorophyll A and the specific reproduction of dissolved organic matter (DOM), it is necessary to use excitation by radiation in the green region of the spectrum (532 nm in this work). To measure the concentration of dissolved petroleum products in sea water, it is necessary to use UV radiation (278 nm in this work). The results of tests of the spectrometer under laboratory conditions on sea water samples containing phytoplankton cells and solutions of petroleum products are described. The results of the work create a methodological and software-hardware basis for carrying out the mission of ecological monitoring of underwater areas with the simultaneous solution of the problem of detecting oil pollution and assessing its impact on the phytoplankton community.