Why does it matter?

Acid rain is an important topic to learn about because it has been detrimental to soil, aquatic ecosystems, forest trees, crop plants, and human health.

Soil: The acidification of soil increases the exchange between hydrogen ion and nutrients such as potassium (K), magnesium (Mg) and calcium (Ca). This leads to nutrient deficiency in soils and causes soil fertility to decline.

Aquatic Ecosystems: Acidic water bodies have shown increased mortality rates, reproductive failure, and skeletal deformities in aquatic life. Many amphibians including frogs, toads, and salamander are sensitive to low pH. Snail and phytoplankton populations begin to decline when pH falls below 5.5. Snails are unable to live in pH levels of 5.2.

Forest Trees: Acid deposition can harm forest trees through foliage or roots. The damage of acid deposition includes reduced canopy cover, crown die back, and whole tree death. Low pH levels cause leaves and needles to discolor and decline. The leaf is most sensitive to damage as epicuticular wax erosion occurs. An injured epidermis leaves the tree viable to disease, greatly declining tree populations.

Crop Plants: Acid rain has physiological effects on crop plants. Acid rain causes photosynthetic rate to decline as well as reduce root lengths and leaf numbers.

Human Health: Acid rain has direct and indirect effects on human health. Direct effects include eye and skin irritation. Indirect effects evolve from contact with materials that have been polluted with acid deposition such as food and water. This consumption accumulates in the body and can form dry cough, asthma, headache, eye, nose, and throat irritations.


Man Made Structures: Acid rain causes deterioration to man made structures. It mostly destroys the paint on cars because of long term exposure. Historical statues also suffer from acid deposition, the Acropolis in Athens has shown great destruction.

Source: Acid rain and its ecological consequences
The Oxford Companion to Global Change
A-Z of the Environment