Human Impacts on Forests

One problem that interests me at this point is the issue of deforestation and the effects it has on the environment.  With greater increases in population, cities grow and the formerly forest environments are no more.  With the decrease in tree populations and overall vegetation, air pollution has the ability to increase even more.  The low amount of concern society seems to have about this issue is alarming.  It is well established that trees and other plants help animals get the oxygen they need.  This includes us, as humans.  The interesting thing is that humans are both the only animals who can understand and observe this fact and the only animals that have a direct influence on the destruction of these resources.  Tree planting programs are starting to be instituted in more places, but cities are also growing and encroaching on as yet unblemished forests.  A variable that would be interesting to observe but would probably be very difficult to quantify accurately is human impacts on forests.  Over time, this has evolved from simply cutting down forests to dumping trash and releasing toxins into the air as well as water sources.  Even the forests that have not been touched by human consumption are affected by the second-hand touch of humanity: polluted streams and air. 

I guess a good variable would be pollution growth - since most of this comes from human interactions with the environment.  The graphs for this sort of thing would probably show an exponentially increasing curve.  (Okay, I'm not sure about exponentially because those curves tend to approach zero, but it would likely look something like that.  The pollution in our air and water is continually increasing because of the waste we create and the exhaust and smoke we release into the air.  I think there would be a steadily increasing trend even into the future, because while more and more people are becoming concerned with the state of the environment, it is difficult to get the entire world onto the same page with reforms that would most likely limit the convenience of day-to-day life.  Today's society is reliant on instant gratification; instituting new transportation and waste management policies would have huge political and societal ramifications.  The beginning of the increase in pollution would be seen around the time of the Industrial Revolution and as more and more advancements are made in industry and technology, those pollution numbers just keep going up.

The parts of the system would include acres of forests and volume of streams (are there kiloliters? I'm not sure how to measure the streams) that are intact and unpolluted; emissions by vehicles and industry; the average waste produced by humans per year; how much clean-up is done every year (so that would be an opposite relationship probably); public opinion for conservation; new policies; and new policies would probably lead to more creative ways of creating pollution.  I think I might be missing some parts, but those were the ones I could readily describe.  Are we going to draw causal loops of our systems?  In this system, as the emissions increase, the areas of unpolluted forests and streams would decrease.  There would also be an opposite relationship between unpolluted area and waste.  As emissions and waste increase, so would public opinion for conservation increase - leading to new policies.  Then would come in the evasion of the new laws and policies.