Ecological Sustainability of Soils of Recreational Zones of the Eastern Shore of Lake Baikal
Authors:   Institute of General and Experimental Biology SB RAS, Balsanova L. D. 
Published: February 2025

Tourist activities on the eastern coast of Lake Baikal have a significant impact on soils. The main load falls on its coastal territory, which is characterized by the greatest vulnerability. There is also the problem of assessing the resistance of soils to anthropogenic impacts, taking into account the natural and climatic characteristics of the territory. Soil studies were carried out within the middle part of the eastern coast of Lake Baikal from the Barguzinsky Bay to the Ust-Selenginsky depression. In soil samples, the pH was determined by a potentiometric method; exchangeable cations - complexometric; organic carbon content according to Tyurin, mobile phosphorus, potassium according to Kirsanov with photocolorimetric ending. Indicators of physical properties were determined by the tube method (water permeability), by the thermostat-weight method using a drill (density of undisturbed soil). The particle size distribution was determined by the laser diffraction method on a particle size analyzer Analysette-22 of the German company Fritsch. The paper considers the natural conditions of the study area. The soils are represented by сambisols, podzols, albic podzols, haplic fluvisols and gleyi-histic fluvisols. They have their morphological features. The particle size distribution of soils varies from loose sandy in Haplic Fluvisols to medium loamy in Leptic Cambisols. Chemical analysis shows an acidic to the neutral reaction of the medium, predominantly low humus content in all soils, except for Leptic Cambisols, the predominance of calcium cations in the absorbed bases, and predominantly low supply of nutrients. Changes in the morphological and physicochemical properties of soils occur under recreational stress. It is known that the properties of soils determine their stability. To assess it, control and threshold values of various soil parameters are required, which is a current global challenge. For this, it is necessary to develop appropriate indicators, taking into account the sensitivity to the impact of anthropogenic factors and the natural characteristics of the region. These include pH, humus content, exchangeable cations, mobile forms of phosphorus and potassium, CEC, density, filtration coefficient, the content of physical clay, percentage of coverage of the site with grassy vegetation, the thickness of litter, and humus strata. Next, we used a point rating for various properties. Points were assigned by soil groupings based on the work of different researchers with additions and adjustments to the analysis of the authors' data. The highest points were given to Umbric Fluvisols (40 points) and Leptic Cambisols (42 points). The least weakly resistant soils are Umbric Podzols and Gleyi-Histic Fluvisols (27 points). The weak stability of the studied soils is due to their formation on sandy sediments and genetic properties. Light particle size distribution, short profile, thin organogenic horizons, and unfavorable physicochemical properties increase the degree of their vulnerability.