ИСТИНА

The main objective of the research was to define a spatial unit for urban landscape assessment that better corresponds to the scale of city planning tasks. The second objective was to study contribution of original natural environment of the city to its present state. The well-known approach to assess urban landscape functions and ecosystem services consists in analysis of spatial pattern of land cover units derived from remote sensing data. Rare and more sophisticated approach consists in allocating and study of homogenous areas within the cities with specific combination of urban artefacts and greenery. We allocated sites, named urban geosystems by analogy with natural geosystems, which included all common biophysical attributes: relief properties, soil moisture and parent material, vegetation; and specificity of grey infrastructure: housing height, density and function. The border between adjoining urban geosystems was lined due to either natural or artificial factor which strongly alters the conditions of mass and heat transfer. To evaluate our approach, we studied statistical relation between chosen indicators of regulating functions of urban landscapes and two representations of spatial pattern. As a first representation we used only interpretation of remote sensing information – metrics of composition of different types of land cover (sealed soils, trees, grass and water) and configuration they formed (patch size, shape, isolation, etc.) in a moving window. Secondly, we performed a large-scale mapping of urban geosystems of Tyumen and studied landscape properties and land cover pattern within the borders of allocated units, and their near and far neighborhood. Indicators of air quality regulation were estimated for winter and summer 2018 by volume of field-measured dust in melted snow and on the surface of tree leaves. Indicators of local climate regulation were characterized by remote sensing estimations of spatial variation of surface temperature in the same seasons. The study shows that joint analysis of multiple landscape properties based on urban geosystem mapping gives better understanding of spatial variability of chosen indicators. Contribution of relief and soil wetness to urban climate regulation is commensurable with contribution of impervious surface and vegetation. Effect of housing type and function on air quality is comparable with the effect of tree vegetation.