Emissions from industry, plus those from vehicles, are the largest sources of air pollution. Photo credit Corel Photo Clipart CD.
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This decrease of nutrients prevents the forest from growing. Acid rain also stifles new growth and kills many of the seedlings. Another effect from acid rain is that the tree's growth is decreased because the microorganisms that live near it die. Acid rain also causes physical damage to the roots, decreasing the rate of growth and eventually leading to the death of the tree. Acid causes the pH level in the soil to fall and when it reaches 4.0, aluminum and other metals are leached out of the soil. The aluminum is filtered through the roots, damaging them, and causing the tree's death. |
| By the time industrial gases fall on the forests, the rain they come down in may be ten or twenty times as acidic as normal (pre-industrial) rain. But the problem doesn't end there. The soil, and lakes and ponds also become acidic. Toxic heavy metals--cadmium, lead, zinc, etc.-- and other substances show up in the soil. |
pollution -- page 2 of 5
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sub-topic
[dying trees]
related topics
[roots] [soil] [water]
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