Ocean acidification

Definition

Ocean acidification is the process by which the ocean becomes more acidic due to the absorption of excess carbon dioxide (CO2) from the atmosphere. This phenomenon leads to a decrease in pH levels in seawater, which can significantly impact marine ecosystems and biodiversity. As ocean acidity increases, it poses threats to organisms that rely on calcium carbonate for their shells and skeletons, such as corals and shellfish, ultimately affecting marine food webs and species diversity.

5 Must Know Facts For Your Next Test

1. Since the industrial revolution, the ocean has absorbed about 30% of the CO2 released into the atmosphere, leading to a decrease in ocean pH by approximately 0.1 units.
2. Marine species like coral reefs are particularly vulnerable to ocean acidification because they require calcium carbonate to build their structures, which becomes more difficult as acidity increases.
3. Ocean acidification can disrupt marine food webs by affecting primary producers like phytoplankton, which are crucial for the entire marine ecosystem.
4. The economic impact of ocean acidification is significant as it threatens fisheries and aquaculture industries that rely on shellfish and other marine organisms sensitive to changes in pH.
5. Research indicates that ongoing ocean acidification could lead to a loss of biodiversity in marine environments, impacting both species interactions and ecosystem resilience.

Review Questions

• How does ocean acidification affect marine biodiversity and what mechanisms are involved?
  • Ocean acidification directly impacts marine biodiversity by altering the conditions necessary for calcifying organisms like corals and shellfish to thrive. As the pH of seawater decreases, these organisms struggle to form their calcium carbonate structures, which can lead to declines in populations. This reduction not only affects individual species but also disrupts food webs and ecological interactions within marine ecosystems, leading to further losses in biodiversity.
• Discuss the economic implications of ocean acidification on coastal communities dependent on marine resources.
  • Coastal communities that rely on fishing and aquaculture are at high risk from the effects of ocean acidification. As shellfish populations decline due to increased acidity affecting their ability to build shells, local fisheries may suffer significant economic losses. This decline can result in job losses and reduced food security for communities dependent on these industries. Additionally, the overall health of marine ecosystems may deteriorate, impacting tourism and recreational activities that are economically vital for these areas.
• Evaluate potential strategies that could mitigate the impacts of ocean acidification on marine ecosystems and biodiversity.
  • To mitigate the impacts of ocean acidification, several strategies can be employed. Reducing carbon emissions through cleaner energy sources and improving energy efficiency is essential for limiting future CO2 absorption by oceans. Additionally, implementing protective measures for vulnerable marine areas can enhance resilience against acidification effects. Research into breeding or engineering more resilient marine species may also help bolster populations that are particularly sensitive to changing pH levels. Collective action at local, national, and global levels is crucial for addressing this complex challenge.

Related terms

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

Calcium Carbonate: A chemical compound (CaCO3) that is essential for the formation of shells and skeletons in many marine organisms, including corals, mollusks, and some plankton.

Ecosystem Services: The benefits that natural ecosystems provide to humans, including food production, water purification, and climate regulation, which can be disrupted by ocean acidification.