Exploring green areas in Polish cities in context of anthropogenic land use changes

Recent decades saw a global degradation of ecosystems and climate change caused by rapid anthropogenic socio-economic growth. The paper investigates spatio-temporal changes in green areas in Polish cities. The study involved two levels: macro (all 936 towns and cities in Poland) and micro (zooming in on Kraków and Toruń) from 2006 to 2018. The authors analysed 64,312 records of statistical data and 32,317 polygons representing areas of specific land use categories in the Urban Atlas with GIS tools and algorithms. Results for the entire country (a macro level) indicate that the area of forests in cities is in decline, but the total share of green urban areas is increasing slightly. Polish towns and cities also exhibit a positive balance of shrub count and a negative balance of tree count. At a micro level, land use analysis indicates a slight decrease in green urban areas, but an increase in the forest area. Moreover, an analysis of the spatial distributions of changes in green areas in Kraków and Toruń demonstrated specific trends. Sites exhibiting a significant decrease in green urban areas were found mainly along main transport routes. Moreover, incomplete green belts around highly urbanised zones turned out to be a characteristic component. The slight differences in results at a micro and macro level are due to a more significant generalisation at a macro level. Micro-level research focuses on an individual case. Hence, it should be used mainly to juxtapose cities, while the macro-level perspective is adequate for cross-country analyses, for example. The results are relevant to urban policies deployed by local and regional authorities, the European Green Deal and climate neutrality.