Check out this slide-show: http://edition.cnn.com/2012/11/01/world/gallery/eco-sols-text-nature-economics/index.html
The idea is to put a monetary value on these natural 'assets' to prove to people that it will be more expensive to destroy them than to preserve them.
The problem is in the way the price-tags are assigned. They are assigned in terms of what direct costs these ecological systems prevent to be unleashed on the economy and in terms of what people think and believe to be valuable/important. For instance - how much do they value having nice green views, or the idea that somewhere far away some tiger is being protected?
So - the value of nature is only measured in terms of human interests. Intrinsically - the value of an animal's natural habitat is - to him/her - priceless. He/she needs it to survive and without it, well - the animal dies. There's no money you can give the animal that will make the animal say "oh okay, if you give me so many million then you can destroy my habitat."
child is worth - one human life - are we seriously thinking we can put a price on something as important as the rainforest, which is responsible for ALL life on Earth?
We've got some serious re-considerations to do if this is how we decide to take care of the Earth - by putting a price on it's apparent value and then, accordingly, either protect it or destroy it. Who are we kidding? We will not make it without nature, we will not make it without the animal kingdom - we will die - it's really that simple. We are not independent of nature - we are a part of it and we are affected by it. It's time we realise that the only way we'll save ourselves is through taking responsibility for the damage we've done and doing what we can to correct it.
In an Equal Money System, the only Value will be Life - not Human Life - LIFE itself - that which humans don't even understand yet. Accordingly, no animal or plant will be treated with less respect and reverence than the human - and so, we will find our place in the world again - among those who have supported us for millenia, while we have done nothing but attempted to destroy them in return.