How green the urban development units in Sofia are: Earth observation and population time series analysis

Abstract

Over the last decades, the pressure that people and their activities put on the environment has increased. Green areas in many cities are diminishing in size due to urbanization, which inevitably leads to a decrease in quality of life. This study uses remote sensing (RS) data for Sofia, Bulgaria, for a period of nearly four decades, analyzing the dynamics of NDVI of the urban development units (UDUs). Statistics for NDVI per were calculated for each UDU for eleven dates in the following years: 1987, 1990, 1992, 1993, 1996, 2000, 2001, 2002, 2011, 2015, and 2020.  An estimate was made of the amount of green vegetation per capita, similar to other coefficients used for population analysis. NDVI profiles for major urban parks showed differences for the studied period. Sentinel-2 data for 2020 was used for visualization of the current situation, in combination with detailed population data for all UDUs. The obtained data will help the decision-making process for the development of UDUs, while the methodology can be applied in any other city worldwide.

Green spaces in Sofia – analyses of spatial distribution

“…An initiative for the green ring of Sofia -a linear park that forms a green highway which connects the central and peripheral neighborhoods, large parks, and gardens, as well as many cultural and sports sites has started. Sarafova (2021) uses remote sensing data to analyze the NDVI and calculate the amount of green vegetation per capita. The analysis shows large differences within the study area in terms of the area of green vegetation that is available in different parts of the city.…”

A methodological framework for mapping and assessment of ecosystem services provided by the natural heritage in Bulgaria

“…The search for new indicators and methods which will ensure quantification at tier 2 and 3 with higher accuracy and lower uncertainty is very much needed. For instance, the use of freely available satellite data from Sentinel2 could be a valuable source for deriving various parameters for both ecosystem condition and services (Sarafova, 2021).…”

Geospatial localization analysis of green infrastructure development assumptions in urbanized areas concerned by air quality: the case of Sofia Municipality, Bulgaria

“…Establishing and maintaining an urban-appropriate GI is one of the most successful solutions in support of other policy and organizational measures to improve AQ, including low-emission zones, transport infrastructure, traffic speed limits, etc [23]. Current analyses of the state of the GI in Sofia show that despite efforts to maintain the natural green and park spaces inherited in the structure of the city, under the pressure of urbanization in some of the most densely populated parts of the city there is a limited presence of green elements [25].…”