Some interesting data for one beech of 30 meters height and in an isolated position has:

approximately 200.000 leaves a foliar area of 1.250 sq. meters approximately 100 billions of chloroplast a total of approximately 200grs of chlorophyll.

During a sunny day

it almost produce 10kg of organic materials it needs almost 9.000 liters of carbon anhydride (CO2) and a total of 30.000 cubic meters of air, it evaporates 200 liters of water and liberates 9.000 liters of oxygen (equals to the daily breath need of ten men)

Folicaduceous and Coniferous Trees - Bruno P. Kremer - Editorial Hispano Europea