Particulate Matter and Vertical Carbon Fluxes in the Water-Bottom System

Commonly, the particulate matter (PM) is defined as the part of the suspended matter which is retained on filters with a pore size of 0.45–1 µm. It includes particulate OM as one of the most mobile and reactive components. At present, several methods for separation and evaluation of the distribution and fluxes of particulate matter are applied. Among them, we can note water filtration through the so-called nuclepore filters (organic polymer films with a pore diameter of 0.45 µm), which are used to determine the concentrations of particulate matter and metals; glass fiber filters preliminary calcinated at a temperature of 450°C and applicable for the determination of C, N, P, and composition of organic matter; sediment traps of various sizes and designs; and the “Flax-camera” and “Survey-camera” systems. The latter performs continuous-discrete measurements of the particle spectra, their sizes and amounts in the water column, while the flaxcamera is installed on the bottom as a sediment trap and shoots from beneath the process of particulate matter accumulation. A special place in these studies belongs to the technology of the observations of particulate matter from underwater manned submersibles such as the Mir, Pisces, and Argus; In addition, optical methods for particulate matter examination are applied. The high efficiency of the use of the optical methods is caused by the continuous-discrete character of the measurements and express mode of data acquisition over space and time. The degree of the light attenuation is closely related to the particulate matter concentration, which allows one to reveal the features of the horizontal and vertical structure of the field of particulate matter, especially when the optical measurements are accompanied by direct particulate matter determinations with the filtration methods providing a possibility to construct regional algorithms linking these parameters.