THE ANALYSIS OF ENVIRONMENTAL RISKS FOR URBAN PLOT OF LAND

Green areas have many functions in increasing and supporting the quality of urban environment. Thus, most factors of people’s welfare depend on and are defined by green areas’ preservation, especially in cities with their concentrated population and intensive anthropogenic impact that create increased ecological risk. A risk is a qualitative or quantitative estimation of a hazard linked to undesirable consequences and losses. Risk estimation consists of several stages: risk identification, risk analysis, risk assessment. The paper is based on long-term field studies of green areas in a dozen Russian cities. The field data were recorded in standard geobotanical descriptions and forms as well as in specially developed author’s ecological assessment charts and defect lists. The main reasons, tendencies and factors of degradation and destruction of green areas were analyzed. A green area’s inability to fulfill its functions was estimated as the main risk. In the structure of the main risk nine event groups or secondary risks were described: destruction and loss of species diversity, its substitution, simplification of vertical and horizontal structure, diseases, infliction of harm, inhibition and loss of decorative value. The authors propose a classification and estimation of the risks, describe the main factors that cause a green area’s inability to fulfill its ecological functions: construction works, works for housing and public utilities, car runovers, recreational activities, trampling down, damaging and littering. The calculation of probabilities for the risk factors was carried out and their patterns were defined.

risk, green areas, cities, loss of species diversity, risk factors, assessment criteria