1) Nature should be allowed to proceed, at least in the portions of the biosphere we allocate to it, to proceed without human intervention. This is based on the belief that we are insufficiently knowledgable to manage nature's resources better than it will do by itself. For example, an oak tree planted in a residential area has an estimated lifetime of about 60 years, with a maximum lifetime of about 150 years. An oak tree that grows in an undisturbed forest typically lives to be 450 years old. The longest living tree is over 7000 years old (look it up!). Are we so arrogant as to think we know what is best for trees like that? If not, don't they deserve to live undisturbed by human kind? 2nd example: Smokey the Bear. Smokey was a campaign by the US Forest Agency to prevent forest fires in National Forest. What they didn't realize is that small brush fires are natural in forest and serve to control the amount of burnable material in the forest. After 50+ years of Smokey's efforts, including rushing in to put out any fires that did occur, the forest floors now how so much debree that any fires that do burn do so MUCH hotter with the flames going up into the crowns of the trees - something that seldom happens in a natural forest. Of course, most forest fires are started by humans, or at least human intervention, such as power line faults.
2) Nature deserves to have a polution free environment to grow in. Strive to give it to nature, and we will be giving it to ourselves as well. A win-win.
3) Nature can help us with everything from anti-biotics to absorbtion of CO2 (think corals that convert CO2 into coral (calcium carbonate) and lock that CO2 up basically forever).
epilog: Some resources, like iron, are more plentiful than others, but all are limited. As stated before, but in line with the polution free goal of the forum, we need to learn to recycle EVERYTHING. Accordingly the cost of goods should reflect the total lifecycle cost of that product. I suspect given that, we could quickly learn to live without a lot of products - like single-use plastic straws.