There’s so much I could go into about how wrong this paper is, but that’d be coming from an “activist” standpoint, so that viewpoint is moot. From a purely objective, “economically-scientific” standing, Costanza is highlighting a necessary evil: in a growing world, we’re going to sacrifice nature for our benefit. That is, as populations rise and as years go on, we’re going to need more space for housing, and a myriad of resources that only the natural environment can supply. Therefore, the areas mentioned in the paper will soon be destroyed and converted into something for the benefit of humankind – a different kind of benefit, however, since the areas in question are already providing some benefit to humanity in its untouched state. (Ex. A forest provides oxygen, but is cleared out for housing development.)
Don’t get me wrong, I do appreciate the paper’s purpose, and again, it is a necessary evil no matter how cruel or heartless it appears from an activist standpoint. Certain natural habitats will have to be destroyed in the future – we’ve already seen this happen throughout history – so we might as well develop a complex system of better pricing the land we need to alter in order to make sure we’re only building things that won’t make us lose the money that is otherwise provided by the habitat if left untouched.
Given the age of the paper, it’s fine to suggest these ideas as a starting point for a valuation system like this. Acknowledging that we’ve been using systems of valuation when it comes to construction sites and the like bring up a valid point on how this is a necessary task. It’s going to happen, we’re already doing it, but why not make sure we tackle this from every possible angle to make sure we’re not shortchanging ourselves? Or nature, for that matter? The paper brings up the technique of valuing based on the ability to replicate them in a synthetic environment, which is fairly ridiculous. Sure, it’d be great to be able to just cut down all the rain forests on Earth and grow them on the moon, but the drastic shift in oxygen quality on Earth would mean that a large percentage of the population would have to go live in those synthetic environments, less they be deprived.
I’m sure more comprehensive systems have been developed by now, so it’s important to read this paper with the notion that it is just a starting point in valuing our entire world, not the final plan.