(Resource limits) could plausibly be ignored by economists only as long as the macroeconomy was tiny relative to the ecosystem, and the encroachment of the former into the latter did not constitute a noticeable opportunity cost. But now we live in a full world, no longer in an empty world – that is, in a finite ecosystem filled up largely by the economy. Remaining ecosystem services and natural capital are now scarce and their further reduction constitutes a significant opportunity cost of growth.
The new economic question is: Are the extra benefits of physically transforming more of the ecosystem into the economy worth the extra opportunity cost of the ecosystem services lost in the transformation? Has the macroeconomy reached, or surpassed, its optimal physical scale relative to its containing and sustaining ecosystem? Is the economy now too big for the ecosystem from the point of view of maximum human welfare?
http://steadystate.org/opportunity-cost-of-growth/