Distilled water has a pH of 7. Acidic substances have a pH closer to 0 while basic substances have a pH closer to 14. One reason the pH level is important in environmental science is that substances that are very acidic or very basic can be harmful to life. Acid rain can be very harmful to the environment in many ways. It has been shown that as acid levels in lakes rise, fish population decreases.
Acid rain can harm plant life and actually kill plants.
Acid rain hastens the deterioration of ancient statues and art throughout the world. Acid rain is formed when pollutants such as sulfur dioxide and nitrogen oxide in the air mixes with atmospheric moisture to form acidic moisture. This moisture can then rain directly on the area in which it was formed, or it can be moved thousands of miles in the clouds by prevailing winds to rain on land far from where it originated. One large natural emitter of sulfur dioxide and nitrogen oxide is Volcanoes. Hawaiian volcanoes produce large amounts of sulfur dioxide and nitrogen oxide.