mouse@uw-beaver.arpa (04/10/85)
From: utcsri!mcgill-vision!mcgill-vision!mouse@uw-beaver.arpa (der Mouse) > sad if these things were gone. Friend, it wouldn't be sad 'cause you > need oxygen to be sad. You ain't got oxygen, you ain't gonna be around > to miss the chipmunks. > .... > (I really expect someone to pop up at this point and say that maybe the > Earthlings are getting their oxygen from moss or something. You are correct. I believe something like 80-90% of the O2 production at the moment is due to green stuff in the oceans. Not moss, not anything else on land, there isn't enough of it (though for sure, every bit will help if things get iffy -- as in ORA:CLE). But there is a *LOT* of plankton and similar beasties out there. Remember, about three-quarters (is that the right ratio?) of the Earth's surface is ocean rather than land. > Even in the dubious possibility that a stable eco-system is possible > based on other sources of oxygen, you can't get there from here without > a whole lot of disruption that would probably kill off old Homo Saps > anyway.) Well, as I said, I don't think it's that dubious. But I have to agree. Removing forests will cause us to lose a lot of topsoil immediately and knock great gaping holes in the ecosystem in other ways I'm sure -- is there an ecologist out there who can elaborate for us? der Mouse {ihnp4,decvax,...}!utcsri!mcgill-vision!mouse
wfi@unc.UUCP (William F. Ingogly) (04/13/85)
> Removing forests will cause us to lose a lot of topsoil immediately and > knock great gaping holes in the ecosystem in other ways I'm sure -- is > there an ecologist out there who can elaborate for us? I *almost* have an MS in environmental sciences (never finished my thesis), so I think I can help out on this question. If you'd like to read up on the science of ecology, try E. P. Odum's text (I can't remember the title right now, unfortunately). Loss of the world's tropical forests would have several unfortunate consequences: 1. A large fraction of the world's animal and plant species live in the tropics. Elimination of the tropical ecosystems would destroy a potentially valuable and little-understood gene pool. How many life-saving drugs have we already found in the tropics, for example? 2. The lateritic soils found in the tropics are low in organic matter, and at least some of them turn rock-hard when exposed to the sun. Angkor Wat (sp?) was built with lateritic soils, and it's lasted for hundreds of years. If the overlying vegetable material is removed, the land beneath would make pretty good landing fields but would be good for little else. Loss of topsoil doesn't occur in the tropics, since there's little topsoil; virtually all nutrients and organic matter are tied up in living organisms. 3. Evapotranspiration from the rain forests has an large impact on the world's weather systems, since tropical trees are incredibly efficient water pumps. I seem to recall that a rain forest puts nearly as much water back into the atmosphere as an open tract of water of equivalent size. The result of the removal of the world's tropical forests would probably be the desertification of large tracts of land in the South American and African continents, which would have unknown consequences for weather in the northern hemisphere. There's a vicious cycle involved here: less vegetation leads to less rainfall leads to less vegetation... As I recall, loss of the world's temperate forests would have some impact but nothing like the dire consequences of the rain forests' destruction. Of course, a large amount of the system's nutrients and organic matter is tied up in the temperate forest's soil, so erosion renders the land useless for agriculture. It's been a number of years since I studied environmental sciences, so I hope others can add to this or patch the holes in my discussion. -- Bill Ingogly
leeper@ahutb.UUCP (m.r.leeper) (04/16/85)
I have to admit that it is at least conceivable that the oceans create enough oxygen so that the dire consequences of my first posting could be avoided. I bow the people who have a better background in ecology than I do (and that is possibly quite a few people on the net.) I find is hard to believe that the land would be so polluted that the forests would have to be shot into space and the oceans could keep on churning out oxygen unscathed. I also still contend the jump to the new ecosystem could be pretty grim (I am responding to the net as a whole, I think mouse agreed with me on this point). Also, I am not sure how secure I would feel if I lived in Kansas with all the oxygen coming from the oceans. :-) I did not cry at the end of SILENT RUNNING, but I can understand that some people did. This is a "go for the emotions" film. I think as a 7-year-old I cried when I read CHARLOTTE'S WEB. That doesn't mean that I think it plausible that spiders really do try to save the lives of pigs. I didn't even then. As a sad story, SILENT RUNNING is a matter of taste. My objection was more about logical flaws. Mark Leeper ...ihnp4!ahutb!leeper
demillo@uwmacc.UUCP (Rob DeMillo) (04/19/85)
> > > Removing forests will cause us to lose a lot of topsoil immediately and > > knock great gaping holes in the ecosystem in other ways I'm sure -- is > > there an ecologist out there who can elaborate for us? > > Loss of the world's tropical forests would have several unfortunate > consequences: > As I recall, loss of the world's temperate forests would have some > impact but nothing like the dire consequences of the rain forests' > destruction. Of course, a large amount of the system's nutrients and > organic matter is tied up in the temperate forest's soil, so erosion > renders the land useless for agriculture. It's been a number of years > since I studied environmental sciences, so I hope others can add to > this or patch the holes in my discussion. > > -- Bill Ingogly Oh, thank you Bill Ingogly and the other gentle-person (whose name I unfortunately don't have...sorry, 'bout that...) for a little sanity. I have been reading SF-LOVERS for a long time, and have become REALLY dismayed by the numerous statements about Silent Running. Now, whether you like the movie or not is a matter of opinion, and that's have the fun of reading book and movie reviews...BUT.... ...good grief, I could not believe the number of people who thought (or seemed to think, correct me if I'm wrong...) that eliminating the world's forests is no big shakes! Yeesh! Certainly, the oxygen supply would continue (for a while, anyway) from algae, but that isn't the end of the story. Plants wuz here furst, and animals depend on them...period. It would eliminate a chunk of the food chain, increase surface erosion, send a lotta dust into the atmosphere, disturb the nitrogen cycle, and a trillion other things that we as mere mortals could only guess at... Sorry if it sounds like a flame without a warning, but seemingly flagerant disregard for ecology flares up a strong "Watt" signal in my brain.... ...there, I had my little say, now back to our regularly scheduled programme.. -- --- Rob DeMillo Madison Academic Computer Center ...seismo!uwvax!uwmacc!demillo / =|-- = \ = [][][] "...I don't know what this thing does, but it's pointing in your direction."