What gave me this impression? Well, when Bro. Nibley said things like this:
"...the earth comes from the hand of the Creator most glorious and beautiful, with great rivers, small streams, and mountains and hills to give variety and beauty to the scene, designed by God as a place of beauty and delight. That is the way we must keep it."
and this:
"Now we all know that Adam could not stay in the Garden. He was expelled and told to get his living by the sweat of his brow. In return for hard physical labor, the earth would yield him of her abundance (Moses 4:23-25). It was a fair exchange—he was to put hard work into the soil, and in return the soil would sustain him. He was to live by work, though, not by plunder. I spent my mission among the fields of Europe, which had been under the plow for literally thousands of years and were still yielding their abundance. After my mission I visited a glorious redwood grove near Santa Cruz, California. Only there was no grove there; the two-thousand-year-old trees were all gone: not one of them was left standing. My own grandfather had converted them all into cash. It wasn't hard to do in those days. You looked up the right people, you got your name on some pieces of paper, and presto! you were rich for a short while and the earth was impoverished forever. I'm pleased to state that my grandfather recognized that there was something wrong with this, that he was not fulfilling the commandment given to Adam, that it was not the kind of work Adam was assigned to do. There was no proportion whatever between the amount of work and the return, between what man took from the earth and what he gave to it. Grandfather took something priceless and irreplaceable and gave in return a few miles of railroad ties. He not only broke the cycle of life so beautifully exemplified in those all but immortal groves, he destroyed it for quick wealth, which served only to corrupt his children and lead them out of the Church. In those days, we enjoyed a feeling of immense prosperity through the simple device of using up in twenty or thirty years those reserves of nature's treasury that were meant to last for a thousand years. With such prodigal waste, of course, we were living high. There's no permanency in economy that takes a hundred from nature and gives back one. There's no survival value in such an operation, which is certainly the business of systematic and organized looting—the very opposite of making a fair exchange with the earth. Above all, it ignores the ancient doctrine of man's obligation to "quicken" the earth that bears for him. The old Jewish teaching is that Adam had a right only to that portion of the earth that he "quickened," on which he labored with the sweat of his brow. Let us not confuse the ethic of work with the ethic of plunder."
I can't help but see in here the admonition, not only to be conscious our usage of the natural resources God has given us, but to adopt a style of living where you give in proportion to what you take. This to me means 1. recycling -- not only to reduce the amount of natural resources we need to use in order to produce things but also to reduce the large amount of waste we dump into our planet every day. 2. eating local foods in season -- to avoid the waste of transport and etc. and reduce the need to use energy to grow out of season and specialized crops and fertilizers (pollutants) that harm the earth (and us). 3. consuming less, living more simply -- again to reduce consumptions means to reduce the need for production and reduces waste. to reuse and make do with things that aren't the newest and greatest, to wear clothes out rather than replace every season, or give up having strawberries on your birthday because they are out of season, might seem like a sacrifice when you're used to having what you want when you want it. but is it possible that these types of changes, sacrifices, were part of what Joseph Smith was talking about in his lectures on faith when he said:
"... A religion that does not require the sacrifice of all things, never has power sufficient to produce the faith necessary unto life and salvation;"
I think it is. I think it's one of the things that shows a more profound immersion in LIVING THE GOSPEL. once we get the more obvious things going, we tend to think "all is well in Zion" and don't look deeper for the many MORE ways there are to live our religion fully. it's not just a social trend to be "green" and to be mindful of how you live on this earth. i felt the truth of Bro. Nibley's words, that it is part of our responsibility in preparing the earth to receive the savior -- to receive Zion:
"The order of Zion is such as will leave the earth as near its primordial, paradisiacal condition as possible."
"We're not making Zion here, but we're preparing the ground to receive it"