How does acid deposition affect aquatic ecosystems?

Acid deposition can lower the pH of water bodies, harming aquatic life and disrupting the ecosystem's balance.

Acid deposition, often referred to as acid rain, is a broad term that includes any form of precipitation with acidic components, such as sulphuric or nitric acid, that fall to the ground from the atmosphere. When this acidic precipitation falls into water bodies, it can significantly lower the pH of the water, making it more acidic. This change in pH can have detrimental effects on the aquatic ecosystem.

Aquatic organisms, particularly those at the early stages of their life cycle, are extremely sensitive to changes in pH. For instance, fish eggs will not hatch at a pH level below 5, and at pH levels below 4.5, most adult fish die. This can lead to a decrease in fish populations, which can have a knock-on effect on the entire food chain. Predators that rely on fish as a primary food source may struggle to find enough food, which can lead to a decrease in their populations as well.

Moreover, acid deposition can also affect the chemical composition of the water. It can leach aluminium from the soil into the water, which can be toxic to many forms of aquatic life. Additionally, the increased acidity can cause a decrease in biodiversity as it can make the water uninhabitable for many species. This loss of biodiversity can disrupt the balance of the ecosystem and can make it less resilient to other environmental stressors.

Furthermore, acid deposition can also affect the physical structure of the aquatic ecosystem. For example, it can lead to the erosion of the banks of rivers and streams, which can alter the flow and depth of the water. This can affect the habitats of many aquatic species and can lead to further disruptions in the ecosystem.

In conclusion, acid deposition can have a significant impact on aquatic ecosystems. It can harm aquatic life, disrupt the balance of the ecosystem, and alter the physical structure of the ecosystem. Therefore, it is crucial to take measures to reduce acid deposition to protect these vulnerable ecosystems.