In Scientific American, November 2009, I found more creative thinking about our environmental problems. The article is The Rise of Vertical Farms. The author, Dickerson Despommier (a professor at Columbia University), has a web site detailing the plan, The Vertical Farm Project – Agriculture for the 21st Century and Beyond
The plan as suggested is to grow food within cities on brown field sites. These could be 30 stories high. City waste water would provide the water, the energy would come from whatever renewable was most locally suitable, supply of the produce would be local, the growing season would be all year long, the plants would be protected from many diseases and weather conditions just by being shielded from the outer environment. A lot of conventional agricultural land could be left to recover and regenerate; absorbing some of the CO2 we need less of in the atmosphere.
Desert and other arid regions could also become food producing areas. I found this a very attractive vision. As the author says, there are many matters to work out, and as I think repeatedly, let’s start small experiments now. The problem that I foresee that I did not notice mentioned is the evolution of plant diseases within these environments. As the world human population is expected to rise to 9.5 billion something new has to be done.