Shkhapatsev A.K., Kazeev K.Sh.

Comparative resistance of biological properties of soils of different types in the Western Caucasus to logging and fires

Soils and soil cover in the middle and low mountains of the Western Caucasus are significantly changed as a result of forest destruction. The causes of forest vegetation degradation can be logging, fires and windthrow. Initial soil alteration may be different: soil mixing and scalping during logging and skidding, pyrogenic impact, windthrow with plant roots, etc., as well as other factors. Further evolution of post-forest soils in the absence or weak erosion follows a similar scenario. The driving force is increased insolation of soil surface at elimination of closed tree crowns, which leads to changes in microclimate and regenerative successions. Changes in soil composition and properties persist for years and decades. The most dynamic and informative are biological parameters, which allow to quickly and effectively assess the ecological state of degraded soils. Generalization of long-term results obtained using an integral indicator of the biological state of soils allowed us to determine the comparative resistance of soils of different types and ecosystems to degradation (fires and logging). In the conditions of the Western Caucasus, biological activity of post-forest ecosystems and soils decreases in the series: Greyic Phaeozem Vertic > Cambisols Cromic ≥ Greyic Phaeozem Eutric ≥ Rendzik Leptosols > Cambisols Dystric.

Keywords: ANTHROPOGENIC IMPACT, LOGGING, FIRES, BIOINDICATION, BIOLOGICAL ACTIVITY, ENZYME ACTIVITY