酸性雨
Atmospheric pollution is pollution that falls from the sky and comes to rest back on earth in the water table and in the lakes and oceans. This air pollution usually comes from smoke and chemicals being thrown into the air from smoke stacks. One of the most troubling facts about atmospheric pollution is that it usually falls hundreds of miles away from its source and therefore is difficult to track and locate, but it is a major contributor to the pollution of not only the Great Lakes but all over the world. Pollution from one country can be hurting another. The best-known type of atmospheric pollution is acid rain. Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the atmosphere. These substances rise very high into the air, they can then mix with and react with water, oxygen, and other chemicals to create pollutants known as acid rain. The effects of acid rain are mostly seen in aquatic ecosystems. As the rain flows through the soil, the acidic water can drain away aluminum from the soil and them flow into streams and lakes. As more acid is released into the environment, more aluminum is also released. There are some plants and animals that are able to tolerate acid rain and moderate amounts of aluminum, but others are not as tolerant and will start to die off as the pH decreases. One of the biggest contributors to acid rain is the burning of coal and fossil fuels.