1.) Urban gardening is fun and useful. You can use all sorts of high-tech methods for irrigation and for controlling water loss, because the incremental cost of extra equipment is low. This is a "big deal" in the American southwest, where we historically tried to grow Kentucky Bluegrass but have now moved to more realistic plantings.
http://www.csu.org/environment/xeriscape/index.html
2.) Farmers are very sensitive to inefficiencies in their methods--because the costs go to their bottom line. My uncle in Nebraska (farming the desert on government subsidies) explained to me in detail how they had modified their central pivot irrigation system to reduce evaporative loss.
3.) The real problem is too many people. Improving farming efficiency just allows a few million more people to survive. Malthus and all that...
You are completely right about the demographic constraints : one of the main problems is population growth. We all know how difficult it is to change that pattern. Even if "Improving farming efficiency just allows a few million more people to survive. Malthus and all that...", we should never hesitate to give those few millions a chance for a better life, be it only with a small family garden. They have the right to become a bit more happy, don't you think ? Prof. Dr. Willem Van Cotthem Beeweg 36 - B 9080 Zaffelare (Belgium)
There is a persistent assumption that by some sort of change to the political or economic or technical environment, the earth will be able to sustain more and more people. We should try to change that assumption, and work to get the global population down by quite a bit. Or, we can wait until Mother Nature does it for us by disease or famine or war...
