Fertility Indicators of Forest Soils in the South-Eastern Part of the Greater Caucasus

Nazaket Ismayilova

Abstract. This article examines the relationships between forest biogeocenoses and environmental factors on the southeastern slope of the Greater Caucasus, with particular emphasis on the role of soil as a key component in maintaining ecosystem stability and productivity. The study identifies the main ecological parameters influencing the fertility of forest soils and evaluates their significance in the functioning and development of forest ecosystems Based on field investigations and the analysis of soil profiles established under different forest formations, actual and optimal environmental indicators were determined for the construction of ecological fertility models. Special attention is paid to the soil block of the ecological model, which includes the soil profile and the physicochemical properties of soils as major sub-blocks. Diagnostic characteristics of soil horizons, including their thickness, structure, color, degree of compaction, and transition features, were used as indicators reflecting ongoing ecological processes such as soil evolution, degradation, erosion, and the effects of climatic changes. The study presents ecological characteristics of brown mountain-forest and brown forest soils formed under mesophilic beech–hornbeam–oak and xerophilous oak–hornbeam vegetation communities in different altitudinal zones of the region. The proposed soil block of the fertility model provides a scientific basis for the development of ecological passports of forest soils and can be used for monitoring the ecological condition of forest biogeocenoses, assessing the degree of their stability or degradation, and supporting the planning of conservation and restoration measures in mountain forest ecosystems of Azerbaijan.

Keywords: ecological fertility model, forest soils, soil profile, ecological passport, forest biogeocenosis, brown mountain-forest soils, beech, hornbeam, oak, Greater Caucasus