DIVERSITY OF NATURALLY REGENERATED FOREST ECOSYSTEMS AND EVALUATION OF THE ECOLOGICAL (SOIL COVER) CONDITION ON THE LANDSLIDE SLOPES OF THE SKHALTA RIVER
Creators: name: Kiknadze, Nino
name: Gvarishvili, Nani
name: Gultamze Tavdgiridze 
name: Lominadze, Shota
name: Jashi, Darejan
name: Sharabidze, Aleksandre
name: Davitadze, Lia
name: Khakhutaishvili, Ana
Publisher: name: Reliability: Theory & Applications
Year: 2024
Subjects: secondary ecosystems
forest
variety
soil fertility
multi-element analysis

description: Adjara is located in a mountainous, exceptionally small region, noted for its diverse and unique natural landscapes. In this area, intense land exploitation disrupts the already delicate balance of the geological environment, leading to the active advancement of natural geological processes. Consequently, the natural regeneration of forest ecosystems following a disaster is understood to be a complex successional process. Over35 years, the regenerated forest ecosystems on the landslide-affected slopes of the valley have been extensively studied. For this research, the systematic arrangement of the flora was analyzed, phytocoenology surveys were conducted, and assessments of soil fertility were completed. The flora of the naturally regenerated vegetation comprises 101 species, which are organized into 32 families and 84 genera. Species-rich families such as Asteraceae, Borraginaceae, Lamiaceae, Poaceae, Brassicaceae, Umbelliferae, Scrophulariaceae, Caryophyllaceae, and Leguminosae are identified. In the research site, as woody plants developed, cenotic relationships gradually emerged among species within the phytocenoses of the pine forest (Pineta; Pinus sosnovskyi), including Pinetum Ramnosum, Alnetum Pinetozum, Alnetum Ramnosum, and Alnetum Salixsosum. Consequently, tiered differentiation occurred, a tree canopy was established, and a specific system for natural regeneration was formed. The chestnut, oak, mixed (polydominant), and beech sub-zones within broad-leaved forests are primarily characterized by typical forest soils. It has been demonstrated through studies that the pH (KCl) of soil samples obtained from regenerated forests is 5.8, indicating a weakly acidic soil reaction. The strong buffering properties of the soil absorption complex are indicated by its high calcium content (336 mg/100g) and magnesium content (43.8 mg/100g). Low levels of total humus and nitrogen content are observed in the soil. The natural forest soil, with a neutral reaction (pH 7.1), is characterized by richness in calcium (378.7 mg/100g) and magnesium (50 mg/100g). Both soils possess a significant reserve of mobile phosphorus and potassium content. In comparison to the regenerated forest soil, the natural forest soil contains 1.65% more humus and 0.132% more total nitrogen. In the vicinity of the surveyed slopes, amid the presence of the derivative-type cascade Skhalta hydroelectric power station, an investigation was conducted on the soil's multi-elemental composition to evaluate the current ecological conditions and identify any toxic elements. Nickel (Ni), mercury (Hg), lithium (Li), antimony (Sb), selenium (Se), thallium (Tl), and vanadium (V) were detected below the detection limit in the 0–40 cm layer of soils. The concentrations of manganese (Mn), cadmium (Cd), lead (Pb), and molybdenum (Mo) in both soil samples exceed the permissible limits. This could be attributed to the proximity of the Skhalta Hydroelectric Power Plant (HPP) to the slopes, where its reservoir is fed by water from the Chirukhi River discharged through the derivation tunnel. Crushed rocks were deposited and spread on the surrounding slopes during the construction of the tunnel, potentially increasing the levels of heavy metals in the soil.