|Rain is supposed to be healthy for plants and trees. It provides them with water, which is essential for their growth. So why is some rain killing and damaging the forests? Because the raindrops contain sulfuric, nitric and other acids. These acids originate in sources such as gasoline and diesel used in cars, fossil-fuel-fired electric power plants, industrial boilers, and residential furnaces. When high concentrations of acidic compounds from such sources mix with atmospheric moisture, they create acids which are deposited in precipitation. This process creates acid rain.|
Above: Traffic is one of the leading causes of air pollution. Below: Large cities build up concentrations of air pollution, and surrounding areas experience poorer air quality, a fact which affects both people and forests. Photo credit Corel Photo Clipart CD.
|Acid rain harms forests in several ways. One detrimental effect of the rain is that the leaves are damaged. For example, the wax on the leaves is worn away, making them less resistant to more rain and insects. The leaves also lose nutrients, leading to the eventual demise of the tree. Furthermore, the fallen leaves do not decompose as quickly because acid rain causes many organisms living in the soil to have diminished respiration rates. This in turn increases the ammonia in the soil because the nutrients that are usually released in decomposition are not being made.|
[water] [leaves] [soil] [fungi] [insects]
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