It is widely accepted that humans have been a major cause of environmental problems since we began creating our cities and especially since the Industrial Revolution of the 20th century. All aspects of the Earth have been affected by humans’ desire to conquer and dominate the planet. Our impact has gone beyond pollution to altering the functioning of many natural systems. These systems include our atmosphere, several land ecosystems and the complex water environments of which we get our drinking water and food sources.
The effects have been universal ranging from ourselves to just every other living organism on this planet. Sure, it sounds like we have ruined everything and probably the best to do is just prepare for the worst of the consequences, but there is a possibility for improvement if we start correcting things now. The very air that we breathe in most major cities is considered unhealthy because of the contaminants that we put in the air through the burning of fossil fuels by our cars and industrial power plants. The residence time of these pollutants is what determines their affect.
Some pollutants are only around for days like NOx with impacts that are largely local, when at levels above air-quality standard there are increases in the number of cases of respiratory disease. Others last a little longer, a few weeks, like SO2, which then are eventually removed from the atmosphere in the form of acid rain. These pollutants are relatively insignificant in comparison with their affect on humanity, like CO2 and CFCs who are around for centuries. These are the chemicals responsible for global warming and the ozone depletion.
Also, coming from the burning of gasoline and diesel fuel is particulate matter, otherwise known as smog, when combined with any of the oxides they present a deadly combination for the health of all living organisms. Some of these chemicals, namely carbon dioxide, also is a result of our destruction of the land. Deforestation of both old growth forests and rain forests have contributed to the amount of CO2 in the atmosphere because this means that there are less trees that can recycle this carbon dioxide to oxygen, thus the impact of the natural carbon cycle is limited.
This mass clear cutting of forests also destroys the habitat of many species that are unique only to those environments, not to mention the possibilities for medical cures that could be found in the plants themselves (25% of prescription drugs in the US contain plant extracts that cannot be synthesized). Then of course we have just developed just about all economically feasible areas, if not destroying the environment, severely damaging it and making it virtually uninhabitable for many species.
Finally, our water systems have become dumping areas. In rivers at least the pollutants are washed away and diluted more by converging flows, but in ground water it sits stagnate because the movement of ground water is so slow it is not purified. Groundwater is a major source of municipal drinking water because of its relative abundance in areas in which there is little other alternatives, like in Los Angeles. Another major problem is the eutrophication of lakes due to agricultural runoff, almost 10,000 lakes are effected.
This causes algae growth, which can use up most or all of the oxygen, leaving none for fish and other organisms. The main solutions to all of these problems are alternate energy sources, more effective ways of waste disposal, with emphasis on recycling, and somehow putting a cap on the growing population. It doesn’t sound impossible, but it involves changing people’s lifestyles, which is the hardest thing to do. If it doesn’t affect that it is much easier to implement a change, but it is also more difficult to think of “solutions”.
To begin any change, education must occur so that the general population understands what problems we are facing. General education is also the best combat against the growing population, countless studies have shown that educated women tend to have fewer children. A more technical approach to these problems is in the development of alternate sources of energy and alternate techniques for disposal of wastes. The best solution would be to combine our efforts into a technique of energy and biomass recovery from wastewater.
Wastewater can also be used to grow plants while itself is being treated through hydroponics treatment. Here plants provide support for growth of biofilms, we provide aeration to the system, then eutrophic nutrients will be removed by assimilation and in some cases both anaerobic and aerobic will occur enhancing biodegradation (80-90% BOD removed, 60% SS removed, 84% of influent NH3 oxidized and DO concentration near saturation).
Phytoremediation is also available for removal of metals, pesticides, solvents, crude oil, landfill leachates and hydrocarbons, with the use of trees that have roots that reach to the water table, thus cleaning groundwater supplies. Finally in the immediate future, where fossil fuels are still being used, we need continue to prevent some of these emissions by modifying combustion processes or by practicing end-of-pipe removal by such devices as catalytic converter on cars and scrubbers on power plants.
We must understand that although these problems may be presented separately they are all linked; air pollution cannot be considered separately from water pollution because air pollutants wash out of the air in rainfall, polluting water. The realization that human societies have a severe and pervasive effect on the environment must come soon, and if we are to avoid catastrophe, everyone needs to learn to operate in a manner that our environment can sustain.