Let me preface by saying that I wholly and enthusiastically endorse a greener world, particularly within cities and near industrial areas. The localized effects both ecologically and psychologically are enormous. I do, however, have one tiny gripe with the “plant a tree, save the world” philosophy though.
It stems, if you’ll pardon the pun, from this:
There is a commonly held belief that by creating a forest, you will magically and permanently remove a large amount of the man made greenhouse gases in our environment. In truth, vegetations is only a short term solution. You see, in its early stages, a forest begins to absorb large amounts of CO2 and other undesirable products. However, in time the forest reaches maturity and the original generation of trees begin to die. With their death they begin to release the contained CO2 and other products at a fairly equal rate to the uptake of new growth.
Depending on the location of the forest and the type of trees, this maturation could be a few decades to a hundred years. While this is a signifigant amount of time on the human scale, it is just as shortsighted as the practices which have caused the original problem.
You see, large, collosal amounts of greenhouses gases have been historically stored in far more stable mediums, such as oil, coal, shale, etc. These mediums take millions of years to form and are not generally reintroduced into the enviroment. And as a lovely a thought as it might be, I just don’t believe that even covering the planet’s surface would provide enough biomass to recapture millions and millions of years of stored CO2 from previous forests. Think about it, how many forests and biological products have been converted into high density CO2 storage in the form of coal and oil during the course of life on this planet?
Recently, there has been some attempts and interest into reinserting CO2 and other products into permeable sandstone and other receptive geological structures. This has been highly controversal and billed as only encouraging the further proliferation of poor industrial/agricultural practices.
I, for one, would like to see more study into this process as I believe that the genie is out bottle and optimism alone will not coax it back in.