Acidification

Definition

Acidification refers to the process by which water bodies become more acidic, often due to the absorption of carbon dioxide (CO2) from the atmosphere and other pollutants. This change in pH can have severe consequences for aquatic ecosystems, affecting the health of marine life, water chemistry, and overall environmental quality. The phenomenon is closely linked to both natural processes and human-induced activities, such as fossil fuel combustion and industrial emissions.

5 Must Know Facts For Your Next Test

1. Acidification is often measured using the pH scale, where a decrease in pH indicates increased acidity; a change of 1 unit on the pH scale represents a tenfold increase in acidity.
2. The main contributor to acidification in marine environments is increased levels of CO2 in the atmosphere, which dissolves in seawater and forms carbonic acid.
3. Acidification can harm calcifying organisms, such as corals and shellfish, making it difficult for them to build their shells and skeletons.
4. Freshwater systems can also be affected by acidification due to acid rain, which results from air pollution and can lead to harmful impacts on fish populations and aquatic biodiversity.
5. The impacts of acidification are not limited to individual species; they can disrupt entire food webs and ecosystems, causing shifts in species composition and biodiversity.

Review Questions

• How does acidification affect aquatic ecosystems, particularly concerning species diversity?
  • Acidification can significantly impact aquatic ecosystems by altering the conditions necessary for various species to thrive. Many organisms, especially those that rely on calcium carbonate for their shells or skeletons, are adversely affected as acidity increases. This can lead to declines in these species, which not only disrupts their populations but also affects predator-prey relationships and overall biodiversity within the ecosystem.
• Discuss the role of human activities in contributing to acidification in both freshwater and marine environments.
  • Human activities play a significant role in acidification through the release of greenhouse gases like carbon dioxide from fossil fuel combustion and industrial processes. In marine environments, increased atmospheric CO2 dissolves in seawater, forming carbonic acid and lowering pH levels. In freshwater systems, acid rain resulting from industrial emissions further contributes to lower pH levels. These changes can drastically alter the chemistry of water bodies and impact aquatic life.
• Evaluate the long-term ecological implications of continued acidification on global marine biodiversity and fisheries.
  • Continued acidification poses serious long-term ecological threats to global marine biodiversity and fisheries. As ocean acidity rises, many marine organisms may struggle to survive or reproduce, leading to shifts in community structures. This decline in biodiversity can destabilize ecosystems, reduce resilience against environmental changes, and impact fisheries that depend on healthy populations of fish and shellfish. Additionally, these changes may have cascading effects on human livelihoods that rely on marine resources for food and economic activity.

Related terms

pH: A measure of how acidic or basic a solution is, with lower values indicating higher acidity and higher values indicating higher alkalinity.

Ocean Acidification: The specific decrease in pH of ocean waters caused primarily by the absorption of atmospheric CO2, leading to negative impacts on marine organisms, particularly those with calcium carbonate shells or skeletons.

Eutrophication: A process where water bodies become overly enriched with nutrients, leading to excessive growth of algae that can deplete oxygen levels and contribute to acidification.