Особливості урбаноземів міста Львова

Abstract

Ґрунтовий покрив міста Львова зазнав докорінних модифікацій за безпосередньої участі людини. Найбільш поширеними у місті вважаються урбаноземи, вони займають близько 2/3 території міста, основною особливістю урбаноземів є те, що вони змінюють структуру ґрунтового покриву і властивості від морфологічних ознак до фізичних та фізико-хімічних властивостей утворюючи новий урбаногенний, який витісняє природний ґрунт з території міста.

The soil cover of the city of Lviv has been changed or has undergone radical modifications by the direct influence of human activities. The urban soils are the most common in the city, occupying about 2/3 of its territory. They change under the influence of vehicles, industry, construction and reconstruction processes and carry a constant load on the natural soils, causing changes in almost all their components: a morphological structure, from physical and chemical properties to microbiological and biochemical parameters, depriving the soils in the city of the ability to perform important environmental functions such as an effective absorption of industrial and automotive emissions, forming a new urban horizon and displacing the natural soils. The natural soils cover has been preserved only in small areas in city and forest parks and on the outskirts of the city. The urban soils of the central area of the city on the territory of the lower front part of the Ivan Franko Park in Lviv have been studied. The study of the soil profiles of this area showed special features: the soil is completely loose, and the thickness of the profiles reaches two meters or more, consisting of an anthropogenic material; a significant number of artifacts in particular (ceramic ware and fragments of pots, glass, metal, leather, as well as numerous finds of ancient coins dating from the sixteenth - nineteenth centuries) have been found in the soil profiles. There are also buried horizons in the profiles of the urban soils, darker in color due to the accumulation of an organic material and a looser consistency, with a high content of the plant roots and the soil microorganisms. The studied soil profiles of this area have testified to the specificity of their features. The soils of this part of the city are completely loose with a lot of an anthropogenic material. If the natural forest soils within a complex green zone of the city are characterized by the high acidity (pH 4.5-4.9) and a lack of nutrients, the anthropogenically altered bulk soils are characterized by a neutral or alkaline reaction (pH 7.1-7.9) and, as a rule, enough nutrients. There is a high content of calcium carbonates due to the presence of inclusions of a lime plaster, which is caused by a slight alkaline reaction, low hydrolytic acidity and a high degree of the saturation of the bases. Different concentrations of humus in the horizons or its absence lead to the fact that the urban soils have many similar and individual features, and only with a small degree of probability can we assume what properties certain urban soils have. There is a significant tendency to contaminate the soil with heavy metals. It is difficult to clearly and unambiguously connect the features of the morphology of the urban soils of the city of Lviv with the functional zoning of a city. Therefore, the condition of the soils of the urban area requires constant monitoring by scientists and special attention because due to the growth of the urban environment almost all their components are changing.