Сontinental ecological-geological systems of hydrothermal soils massifs of South Kamchatka

The authors identified the main features of continental (land) ecological-geological systems (EGS) of hydrothermal soil massifs at the local level using the example of thermal fields in the south of the Kamchatka Peninsula — the East Pauzhetsky geothermal field. The field is located on the northwestern slope of the Kambalny volcanic ridge at an altitude of about 300 m above sea level. It has a shape elongated in the sublatitudinal direction with linear dimensions of the order of 350×100 m. From the surface, the thermal field is composed of hydrothermal clays formed due to the complete degeneration of andesites during interaction with gas–hydrothermal fluids. The abiotic and biotic components of the EGS data were analyzed. The specific features of the lithotopes of the considered EGS, represented by massifs of hydrothermal-metasomatic soils with a certain topography, a characteristic hydrotope, as well as geochemical, geodynamic and geophysical fields developed within their boundaries, have been established. The characteristic features of the lithotope of the EGS under consideration are: 1) the essentially clayey composition of the soils in the uppermost part of the section; 2) elevated temperature causing a temperature anomaly; 3) acidic–slightly acidic environment of pore solutions in the near-surface horizon and alkaline at depth; 4) changed (compared to parent rocks) characteristics of structure and texture, indicators of physical, physico-chemical and physico-mechanical properties. Lithotopes, in turn, determine specific edaphotopes on their surface, as well as the development of peculiar biocenoses: thermophilic microbiocenoses, communities of characteristic plants and animal thermophiles. The EGS of hydrothermal soil massifs is characterized by horizontal zoning, which manifests itself in all of its components and is caused, first of all, by the presence of a zonal temperature anomaly in the hydrotherms under consideration. The main determining factor in the formation of the specific features of this EGS is the originality of its lithotope, represented by an array of hydrothermal-metasomatic soils with vertical and horizontal zoning. The identified features in the composition and structure of the analyzed EGS must be taken into account during engineering and environmental studies and engineering and environmental surveys at similar objects.