The value of air purification and carbon storage ecosystem services of park trees in Warsaw, Poland

This study assessed, in monetary terms, the ecosystem services provided by trees growing in public parks and garden squares in Warsaw, Poland. It focused on the valuation of two services: air purification (measured as an annual benefit stream in EUR/year) and carbon storage (measured as a fixed value at a given point in time in EUR). The study was conducted using the Avoided Cost Method with i-Tree Eco software. The initial calculations were based on data obtained from 41 selected green spaces in Warsaw. Subsequently, the results were extrapolated to all public parks and garden squares. The findings indicate that the average economic value of the NO2, SO2 and PM2.5 pollution removal ecosystem service provided by trees in Warsaw is around 3 EUR/tree/year. On average, one hectare of a public park in Warsaw provides this service at a value of 408 EUR/ha/year, while one hectare of a garden square provides this service at a value of 347 EUR/ha/year. With regards to the carbon storage ecosystem service, the results showed that the average economic value of this service is around 170 EUR/tree. On average, one hectare of a public park provides this service at a value of 22.4 thousand EUR/ha, and one hectare of a garden square provides this service at an average value of 18.9 thousand EUR/ha. By extrapolating these results, the total value of the air pollution removal ecosystem service provided by trees growing in all public parks and garden squares in Warsaw was estimated to range from 393 to 560 thousand EUR/year. The value of the carbon storage service ranges from 23.3 to 30.2 million EUR.