Cows alter the biosphere (and all wild plant eating animals). In fact all animals alter the biosphere.
Natural fires alter the biosphere. In fact, my biosphere sucks right now. Fires down in Georgia and Florida are sending smoke so thick (northern Alabama) that visibility is way under 1 km.
Just curious, anybody north of me seeing this?
Mike
edit:
http://www.firedetect.noaa.gov/viewer.htm