: Just out of couriosity, how much oxygen production is lost when trees are cut
: down? In my experience, bare dirt is almost at once covered with oxygen
: producing vegetation (weeds, to the unappreciative). I don't think any
: more sunlight reaches the ground than in the forest. Even where row crops
: are planted, they set the rows so minimal sunlight is wasted, and the
: fields are bare only when the sun is low, the days short, and the trees
: dormant)

: Anyway, when I was in school we were taught that most O2 was manufactured by
: phytoplankton in the seas. This theory seemed to lose ground about when
: the jungles turned into "rain forests"

: Anyway, does anyone have any numbers?

I do not have any number, but you forget that the detremantal factor is rainfall and amount of sun light. Obvious to all of us rainfall is no problem in rainforest and near the equator,where most rainforest are, sun light is never short of. These all make make rain forest important in O2 production. On top of all these, diversity! You cannot find more of that anywhere else. developing copuntries practice clear cutting that wipe out most species within and limited acess to others beyond the border. It's devastation goes beyond what we can understand. It is totally different from falling a single tree. That is why I make a point not to use tropical hard wood even when I worked thirty years with my dad in his cabinet building bussiness. I hoped our great grandchildren could still enjoy the same or better resourses we have.