One of the most devastating side effects of pollution is increased acidity in rain and groundwater. This affects animals and plants, and has long-term implications for our environment.
The pH Scale
The pH scale measures the acidity or alkalinity of a liquid, from 0 to 14---7 is neutral, anything below 7 is acidic and anything higher is alkaline.
Rain and groundwater tend to be naturally slightly acidic, usually no lower than 6 on the pH scale. Most plants and animals tolerate this level of acidity without any problems.
Byproducts of air and water pollution are acidic. While natural alkaline substances in the soil can reduce their impact, the result of such pollution is often a much more acidic environment than normal.
When low-pH water spreads via precipitation, it is called acid rain. As it soaks into the ground and collects in streams, it can drastically change the ecosystem.
As pH drops, more fragile plants and animals may become sick and die. In addition, a pH change in a body of water can affect the microorganisms living within, with domino effects that can destroy the entire aquatic food chain.