Dan Hook
guldann@ix.netcom.com
----------
> From: Mitchell Porter <mitch@thehub.com.au>
>
> "Although it is possible to imagine generating
> human welfare without natural capital and ecosystem
> services in 'space colonies', this possibility is
> too remote and unlikely to be of much current
> interest. In fact, one additional way to think
> about the value of ecosystem services is to
> dteermine what it would cost to replicate them
> in a technologically produced, artificial
> biosphere. Experience with manned space
> missions and with Biosphere II in Arizona
> indicates that this is an exceedingly
> complex and expensive proposition. Biosphere I
> (the Earth) is a very effective, least-cost
> provider of human life-support services."
>
> No figures are provided in support of these
> claims about space-colony economics.