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The laser-induced breakdown spectroscopy (LIBS) and laser-induced fluorescence (LIF) methods were applied for element and pigment concentration detection of marine water and phytoplankton samples. The spectra of plasmas generated by focusing the first harmonic λ = 1064 nm of a pulsed Nd:YAG laser on the liquid surfaces and phytoplankton samples in atmospheric pressure are described. Some of the chemical elements detecting by LIBS in the marine water (Na, Ca, Mg) and phytoplankton (Mg, Ca, Na, Fe, Si, Al) were defined. The radiation of second harmonic λ = 1064 nm of a pulsed Nd:YAG laser was used for phytoplankton pigments and dissolved organic matter detection by LIF. The results of joint application of LIBS and LIF measurements for phytoplankton communities state investigations inside Okhotsk Sea are presented.

The Laser-Induced Breakdown Spectroscopy (LIBS) method was applied for detection of phytoplankton and marine water elemental composition. The results of the sea water quality monitoring and phytoplankton element composition measuring obtained in the Okhotsk coastal sea water during scientific research expedition in 2000-2001 years are described.

Experimental studies of the laser-induced Al plasma expansion during laser pulse into ambient air under pressures of 76 - 760 Torr was performed using 2-channel ADC attached to photomultipliers. Simultaneous measurements of the temporal dynamics of entire plasma emission and neutral Al 396.15 nm emission vs. laser pulse form were carried out with resolution 10 ns. It was detected dualization of a plasma head front, corresponding laser Q-switched pulse. This phenomena may be caused by decay of the laser-supported detonation wave. Distance on which plasma front observed vs. time was obtained under different pump energy of Nd:YAG laser. These results show that plasma expansion dynamics can be described by fast ionization wave model and laser- supported detonation wave model depending on laser pulse form.

Laser plasma generated on the surface of solid targets located in gas atmosphere leads to the formation of a strong shock wave, which changes thermodynamic and spectral plasma characteristics accompanied by Stark effect. The registration of Stark shift and broadening of emission spectral lines allowed us to determine electron temperature and electron density for the ambient gas pressure range of 200 - 1200 Torr without considering presence of local thermodynamic equilibrium in the studied volume of aluminum plasma. The electron temperature and density of plasma increased along with gas pressure, which was explained by the formation of the more intensive shock wave. The velocity of laser plasma expansion in vacuum was obtained by measuring Doppler shift of weakly broadened lines of emission spectra, collected at two different angles from the normal of target surface. The measurement of line broadening, caused by square Stark effect, gave us an estimate of electric field in aluminum plasma. For Q- switched Nd:YAG laser operating at a 1.064-micrometers wavelength with a pulse energy of 0.6 J and a time duration of the laser pulse of 20 ns, the electric field in the studied plasma volume was 18 kV/cm for ambient gas (helium) pressure of 760 Torr.