Originating in nature, the combination of spongin protein with silicon dioxide extracted from seawater by silicatein protein presents a natural nanocomposite material of unique optical and mechanical properties. Mechanically, it combines the elasticity of protein with the flexibility and durability of silica. The light propagation inside spicules of glass sponges is of substantial interest for developing novel elements for photonics applications. The glass sponge spicules have remarkable light guiding properties. Our experimental research on passing laser pulses through spicules of Hyalonema sieboldi and Pheronema sp. reveals a concentration of guided light in the paraxial region. The multi-layer cladding of glass sponge spicules produced by nature has an obvious analogy with some contemporary artificial microstructured optical fibers. Our researches have shown that the core diameter and cladding layers thickness of the spicules of H. sieboldi and Pheronema sp. glass sponges are appropriate for causing photonic bandgaps in the infrared, visible, and ultraviolet wavelength regions. This enables singlemode waveguide and Bragg light propagation regimes in the spicules and provides exciting prospects of using them for the development of fundamentally new integrated optical elements based on peculiar waveguide properties of such structures, e.g., single-way waveguides (optical diodes) with increased mode field diameter and unique frequency and dispersion characteristics. Also, we have investigated the dynamics of propagation of intensive ultra-short pulses with durations T (0) < 40 fs through various patterns of spicules. Comparative analysis of the spectra of the output signals has shown that chromatic dispersion in spicules is considerably reduced, which can be explained by waveguide dispersion prevailing over material dispersion because of the multilayer structure of the cladding.

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In this paper, we review photonic methods and technologies that are promising for monitoring the ocean and atmosphere and have been implemented mainly in recent years at the Institute of Automation and Control Processes, Far Eastern Branch, Russian Academy of Sciences. We present results of lidar studies that have made it possible to understand key features of ocean – atmosphere interaction processes under continent – ocean transition conditions, which determine specific features of the atmospheric aerosol distribution, small gaseous components of the atmosphere and its optical characteristics. We consider methods and tools for combined optical and laser fluorescence monitoring of the ocean surface. Particular attention is paid to results of research on remote methods and tools for real-time laser-induced and laser fluorescence environmental monitoring of the ocean, including specialised fibre-optic probes and mobile underwater robotic systems. We present results of the development and investigation of highly sensitive, noise-proof fibre-optic hydro- and seismic/acoustic sensors for remote monitoring of the ocean and robotic systems for underwater laser protection of marine vessels, hydraulic structures and oceanographic instruments against the negative impact of biofouling.