In the Eastern United States, there is evidence of nitrogen saturation in some forests. Nitrates can remove additional calcium and magnesium from the soils. Continued nitrogen deposition may alter other aspects of the nutrient balance in sensitive forest ecosystems and alter the chemistry of nearby lakes and streams. This may lead to unwanted growth of algae and other nuisance plants. Table I shows estimates of the percentage of nitrogen deposition which comes from the atmosphere.
Acid rain can react with aluminum in the soil.
Trees can not absorb naturally occurring aluminum, but acid rain may convert it to aluminum sulfate or aluminum nitrate. These can be absorbed by the trees, and may adversely affect them. Acid rain has not been shown to be harmful to human health, but some studies are considering whether some of the particles which can be formed from sulfate and nitrate ions can affect respiration. Acid deposition has also caused deterioration of buildings and monuments. Many of these are built of stone, that contains calcium carbonate.