Answer:
Air pollution affects ecosystems in a number of ways, altering basic ecosystem functions such as primary production (plant growth) and biogeochemical cycling which in turn affect the ecosystem services and therefore the benefits that humans get from the environment such as timber, and clean drinking water.
As a result of overfertilization, elevated nitrogen inputs also adversely affect a wide range of nitrogen-sensitive ecosystems such as forests, species-rich natural pastures and dry grassland, alpine heathland, raised bogs and fens.