The Experimental Lakes Area (ELA), was founded in 2014 by Mr. W. E Johnson and John Vallentyne, a unique collection of around 58 formerly pristine lakes, located around the Kenora District Ontario, Canada area used as a research station. The ELA investigates the aquatic effects on various lakes, ecosystems and species. Various lakes have been experimented on, however ‘Lake 223’ was the first whole-lake ecosystem study on acidification and the largest lake being ‘Lake 302’, a double basin experiment with one basin acidified by nitric oxide and the other by sulphuric acid. Both ‘Lake 223’ and ‘Lake 302’ were tested on in order to investigate acidification in large aquatic ecosystems and its consequences. Over a five year period, scientists gradually added more and more acid to the lake by reaching an annual target pH level. By 1981, the pH of ‘Lake 223’ fell from a normal pH of 6.7 to 5.0, a significantly more acidic pH. Major, irreversible changes were seen in the lake ecosystem such as, many critical species, such as Mysis shrimp, crayfish and fathead minnows were completely wiped out. Even though the pH did not reach past 5.0, the lakes biodiversity and whole ecosystem was severely disrupted. Concerning ‘Lake 302’, after five years of experiments, it was found that sulphuric acid was about 33% more potent than nitric acid. The sulphuric acid basin declined to a pH of 4.5, lower than ‘Lake 223’. This study concluded that littoral communities were very vulnerable to changes in pH. Therefore, since 2001 no acid has been added to ‘Lake 302’ and the plant and animal life of the lake is gradually recovering. Weighing out the pros and cons of the experiments undertaken at both ‘Lake 223’ and ‘Lake 302’, the beneficial outcomes end up outweighing the consequential outcomes. Without using a natural setting, for experimental purposes, the results may not be as accurate and precise as they could be as experimental research can create artificial situations that may not relate closely to a real-life situation. This is due to experimental conditions being very controlled, leading to the reactions of these tests possibly not being true indicators of their traits in a fully natural environment. In a laboratory environment, the validity of the project lies almost completely in the hands of humans and human error is very likely, furthermore leading to an inaccurate and unreliable experiment that could easily be completed in a more natural setting, such as a lake. However, when conducting experiments in a natural environment a wide variety of species (both plants and animals) are affected which greatly affects the wellbeing of the whole ecosystem. After constant experiments, the vegetation in the habitat is almost always destroyed, moreover starving the animals, wiping out key links in the food web overall causing an unbalanced, unhealthy ecosystem. Secondly, in the case of a laboratory experiment, conditions not found in a natural setting can be generated in an experimental setting. Conditions that may take longer to occur in a natural environment may take place more quickly in an experimental setting, without destructing any key parts of the ecosystem. Overall, in my opinion, the advantages of undertaking experiments at ‘Lakes 223 and 302’ exceed the disadvantages as I believe that the benefits to society and scientific research as a whole will be worth the small harm that the ecosystem will endure. Also, after the research system at the ELA, our knowledge on processes, such as acidification, will be much broader than without undertaking experiments on natural settings. Human contribution to the environment is a critical issue and is only going to get more and more dangerous if we as a race do not change our ways. Acid rain is one of the many consequences of our harmful actions, it is a type of ‘rainfall made sufficiently acidic, due to its elevated levels of hydrogen ions and atmospheric pollution that it causes environmental harm, typically to forests and lakes’ (Acid Rain. (n.d.). In Oxford Living Dictionary.). The main causes of acid rain are the industrial burning of coal and other fossil fuel, the waste gases from which contain sulphur and nitrogen oxides which combine with atmospheric acids to form acids. The known effects of acid rain are most commonly found among aquatic areas, for example streams, lakes or marshes where it can be very harmful to fish and other species present. Acid rain water is as harmful as it flows through the soil and often ends up draining the aluminum from the soil clay particles and then flowing into streams and lakes. Carbon dioxide in the air can dissolve in rain water to form carbonic acid, H2CO3 (CO2 + H2O ? H2CO3). Carbonic acid is a weak acid which partially ionises to form hydrogen ions (H2CO3 ? H+ + HCO3-), the hydrogen ions from carbonic acid give natural rain water acid pH value of 5.6. Over the last 100 years, the rain water has become far more acidic than it used to be, as the emission of pollutant gases, such as sulfur dioxide (SO2), and the level of coal burned in electricity stations (when coal is burned sulfur impurities form sulfur dioxide) has significantly increased due to a massive industrialization of our world and society. The gas is also produced when fuels from crude oil is burned. When sulfur dioxide is released into the air it reacts with water and oxygen to form sulfuric acid, H2SO4-. Sulfuric acid is a very strong acid and it ionises completely to hydrogen ions (H2SO4 ? 2H+ + SO4 2-), subsequently this gives rain water an acidic pH of below 5.0.Acid rain has been a significant issue in our society and has repeatedly been talked about, therefore Canada’s government has created a federal-provincial team to devise a common solution, the 1985 Eastern Canada Acid Rain Program, a science and monitoring program. This established the basis for the federal government to seek reductions of flows of acid pollutants from the United States. Canada also asked for support from other countries with similar concerns; this led Canada to join with the European nations and the United States to sign the 1979 United Nations Economic Commission for Europe Convention on Long-Range Transboundary Air Pollution (UNECE LRTAP) and later sub-agreements on sulphur and nitrogen oxides. Finally, both Canada and the United States have agreed to cut sulphur and nitrogen oxides emissions as well as ensure visibility protection, prevent the deterioration of clean areas and conduct emissions monitoring. After researching the topic of acidification, natural and experimental research as well as the acid rain problem, I am still wondering what else the Canadian government has in mind to help the issue of acid rain and also what scientists believe on how the future of acid rain will affect our society and world concerning what we are doing to do with it at the moment.