I recently finished reading Masanobu Fukuoka's "Sowing Seeds in The Desert," which has become something of a must-read for homesteaders and conservationists recently, as was his older book, "The One-Straw Revolution."
While there are some things I really appreciate about his low-interference approach to growing vegetables and trees, when he steps into the larger arena of reining in the growing desertification of our planet, I think he makes a huge miss, not a hit.
The idea of growing non-native species in areas of land which have become deserts is initially appealing; after all, who doesn't think that stopping good land from becoming a desert is a great idea. But it's only a good idea on the surface. By introducing non-native legumes and grass species to a landscape that has never produced them, they have the potential ability to spread and eventually crowd out native plants. Native plants are designed to feed the native wildlife at an appropriate pace (think about what happened when humans began growing grains in the grasslands of the midwest and the wild rabbit population exploded). In other words, if you start monkeying around with the wild landscape, you do so at great risk to what native plants and wildlife are left in the surrounding areas.
As far as the destruction that's taken place on our planet due to commercial agriculture, I completely agree with him about its effects, especially when he discusses places that were once rainforests and are now barren fields where commercial crops were briefly grown and then failed, once the soil's nutrients were used up. But I don't believe, sadly, you can just seed-bomb and grow a new rainforest there.
But, left alone, some places could indeed revert to something close to what they once were, if allowed to do so. If you take California's San Joaquin Valley as an example (where I lived for 25 years), it is a great example of a piece of land that's been used for a purpose that, under normal circumstances, Mother Nature would never have allowed. Crops have been grown, soil has been enriched, and large quantities of water have been brought in, diverted from other places.
Now, if for some reason the world had to leave this area suddenly and not grow there anymore, eventually, with time, the native grasses would once again populate the area. If you restored the rivers that used to flow there by un-doing the mountain dams, you'd even have some gorgeous, lush greenery in places. But most of the area would, naturally and as God created it, be a dry grassland with some vernal pools here and there, greener as you got closer to the Sierras. And while I am sure you could green up the whole place by introducing clovers and other green covers, that's no more natural for that area than rows of crops and orchards are.
Having said all this, I am thinking that perhaps I got started with the wrong Fukuoka book. I am actually looking forward to reading his other titles, which apparently deal with more that the small-scale farmer can do on his or her own land. Those ideas and suggestions may be more practical for me and therefore, more understandable. I could certainly see adding some, say, alfalfa and clover to our pastureland to increase its ability to feed our future livestock.
But as for changing the world, my own opinion is that mankind has done quite enough of that, and that the best thing we can do is leave the truly damaged places (like former rain forests) alone, to recover and to heal -- and either revert to what they once were, or become something completely new and different.