PECULIARITIES OF THE TERRITORY OF THE CITY OF LVIV (UKRAINE) AND THEIR INFLUENCE ON THE HYDROLOGICAL REGIME AND EROSION PROCESSES

Abstract

The object of research is the territory of the city of Lviv (Ukraine). Lviv (geographical coordinates: 49N50, 24E00) is the largest city in Western Ukraine, with a population of over 720,000 inhabitants. The city is located in the western part of the Volyn-Podilska Upland, on the line of the Main European Ridge of the Baltic and Black Sea basins. Subject of research is relief parameters (maximum, average and minimum heights, vertical dismemberment and steepness of the surface) and land use characteristics (building intensity, phytocenotic cover). The purpose of research is to study the features of the territory of Lviv from the standpoint of influence on the hydrological regime and erosion processes. Methodology. Peculiarities of the territory of Lviv were studied by processing topographic maps using aerial photography materials and route surveys. Morphometric analysis of the relief was performed on topographic maps of scale 1: 10000 by dividing the map into elementary squares with an area of 0.25 km2. The research covers an area of 100.25 km2 (401 elementary squares). Within the elementary squares, the maximum, average and minimum heights of the territory, the depth of local erosion bases, the average surface steepness, the intensity and nature of construction, and the features of vegetation were determined. Results. The territory of Lviv is characterized by a variety of relief conditions and related nature of surface use. On the basis of morphometric maps of maximum and minimum heights, vertical dismemberment and steepness of the surface, we can distinguish the flat peripheral part of the city and the middle band of elevations. The asymmetry of the territory of Lviv in relation to the watershed causes various potential dangers of erosion processes and related unproductive moisture losses. The intensity of construction increases from the periphery to the center, with the exception of modern multi-storey buildings of the Sykhiv massif and industrial areas in the western part of the city. Low specific weight of waterproof coatings is characterized by the eastern and northern parts of the city with a complex relief. The largest amount of greenery is concentrated in the eastern part of the city (Vysokyi Zamok Park, Shevchenkivskyi grove, Pohulyanka Forest Park, Lychakiv), where surfaces with maximum relative heights predominate. The great variety of the underlying surface on the territory of Lviv causes different conditions for the formation of surface runoff and associated unproductive moisture consumption. The high potential danger of erosion processes is primarily noted by the structural-denudation level of Roztochia, which is characterized by the highest values of surface steepness. Complex relief conditions, intensive anthropogenic impact determine the need for anti-erosion organization of the city and measures aimed at optimizing hydrological processes. Scientific novelty. One of the criteria that characterizes the degree of landscape transformation within the city is the intensity of construction, which is determined by the proportion of watertight areas in the overall balance of the territory. Peculiarities of spatial arrangement of elementary plots with different intensity of construction in combination with relief parameters and land use scheme are determined. Practical significance. Knowing the parameters of the terrain and the peculiarities of land use, it is possible to determine the potential intensity of erosion processes in the territory of Lviv, to assess the level of anthropogenic changes in the hydrological regime.