Thank you Jason,
I could use i-Tree Eco for my project but does this tool take into account growth of plants over the years? Or is it consider a constant size for each tree?

I'm searching about a tool for te calculation of long-term environmental benefits from a new tree planting project in Italy. I'm particularly interested in calculation of PM2.5 removal on a 40 years lifetime period, starting from little trees with DBH of 1 to 3 cm. I've tried to use i-Tree Planting ...