What is the most immediate effect of acid rain?

The most immediate effect of acid rain is commonly seen in aquatic ecosystems, particularly concerning the health of fish populations. Acid rain, which is formed when pollutants such as sulfur dioxide and nitrogen oxides mix with water vapor in the atmosphere, results in increased acidity levels in water bodies. This immediate change in pH can lead to harmful conditions for aquatic life.

Fish and other aquatic organisms often thrive within a specific pH range. When acid rain lowers the pH of lakes, rivers, and streams, it can disrupt their biological processes. This change can lead to decreased survival rates for fish, as well as reduced reproductive success and overall biodiversity in affected ecosystems. Toxic metals that may have been previously bound to sediments can also become more soluble in lower pH, exacerbating toxicity in the water and impacting fish populations even more.

In contrast, while the decline in plant growth, increased rates of erosion, and higher incidence of respiratory illnesses are significant environmental and health issues associated with acid rain, they typically occur over a longer timeframe or involve factors that may not present as immediate consequences compared to the direct impact on aquatic organisms.