This may not be of value to anyone here, but...
When I was reading 'The Age of Inflation' by Jacques Rueff, he basically said that a gold standard (actually, gold convertibility) would solve the population and environmentalism problems itself.
The idea behind it (from memory) is that in our current system, in which we have inflation, there is a constant push to beat certain profit margins, at any cost. This means that companies cut corners in order to be more profitable, because they have to be.
And for population, I'm struggling to remember, but it was something along the lines of people taking responsibility for their own resource consumption, or something like that. It's hard to have 10 kids if you can't support them (but of course you can't just put kids back where they came from either).