It's not easy being Green This is the topic of one of the books I have not written.
But at least I have the sketch of the book ready. I've written it many years ago. It goes like this, from memory:
1. Natural resources (bear with me for a while here, this sketch is quite old, and it takes for granted some terminology that fell out of favor since) are very often mismanaged.
2. Their mismanagement has terrible consequences (both short run and long run).
3. The consequences can be fairly understood as the "externalization of costs and benefits". (Insert longish explanation here if this is not clear -- it is an economics concept).
3.1. (As regards the OP): the externalization is usually conceived as pertaining to human subjects, but there is no intrinsic obstacle to extending the notion to non-human subjects.
4. The general framework that fosters these externalizations is the "Tragedy of the Commons" (Hardin, 1968; google it if you haven't heard about it).
So far this has all been more descriptive than prescriptive. But the prescription starts here:
5. We have, now (this was in 1998, more or less -- of course the situation is much improved since then), the technical means to enable valuation and to produce accurate estimates of the externalized costs and benefits in many commonplace situations. My example back then (in tune with my career specialization) was water use issues. It is child's play (theoretically) to estimate the cost of (a) cleaning up a polluted water body on an on-going basis and (b) prevention of pollution in the first place (e.g., by sewage treatment facilities). It is then easy to compare the two costs; and if reality is following the more expensive cost, it is, obviously, because some parties, without a say in the decision-making process, are bearing the brunt of these costs.
5.1. The situation is not so easy in other contexts. How much is a species of insect worth? What kind of ecosystem services is it involved with, and what is the value derived from them? Etc. (Note that here I was skipping the ethical problem of "who are we to put a price tag on another species", but this can be dealt with separately).
6. So, the strategy for better dealings with the environment becomes clear:
a. Reduce, as much as possible, externalizations. In other words, people who are responsible for X must pay the costs for X; people who benefit from X must be responsible for X.
b. When externalisation is (still) inevitable due to technical shortcomings of our engineering and scientific practices, act as if it could be reduced by the individual. This is an ethical imperative. People must increase their awareness of costs and benefits derived from their surroundings. Costs and benefits are not solely (or even mostly) economical in nature; the pleasure from a waterfall, the feeling of wellbeing from a well-preserved urban forest, etc. If you are aware of some benefit accruing to you, take responsibility for it. If you are aware of some cost imposed by your activities, try to pay for it. Summing up, if you are an agent (negative or positive) of externalization, be aware of it, and adjust your behavior so as to minimize externalization.
6b may sound utopic, but I don't think it is (and I strive to practice it in my own life). It is more a matter of awareness than of calculus or anything more utilitarian in nature.