Ocean Acidification and its Effects on Calcium Carbonate Marine Organisms
Ocean acidification is a more current issue we are facing as a society. With ocean acidification, a chemical reaction is created between the ocean water and shelled marine organisms. This reaction causes a severe detriment to the ocean’s food chain and the social factors of humans. Find out more about the topic below.
What is Ocean Acidification
Ocean acidification is the process by which the ocean’s pH decreases due to the uptake of carbon dioxide (CO2) from the atmosphere. As the ocean absorbs more carbon dioxide, the pH decreases, and the ocean becomes more acidic. This process has several impacts on ocean ecosystems, particularly on organisms that use calcium carbonate (CaCO3) to build shells and other structures.
Calcium-carbonate organisms are particularly vulnerable to ocean acidification. The decrease in pH reduces the availability of carbonate ions, making it more difficult for these organisms to build and maintain their shells and other structures. This can lead to reduced shell growth, reduced fecundity, and decreased survival rates. In extreme cases, continued ocean acidification can lead to the dissolution of existing shells and other structures, leading to population declines and, eventually, extinction.
In addition to the direct effects of ocean acidification on calcium carbonate organisms, there are also indirect effects. For example, ocean acidification has the potential to disrupt the food web by reducing the availability of food sources, leading to a decrease in overall population sizes. It can also affect the ocean’s carbon cycle, leading to further changes in the chemistry and biology of the ocean.
What Causes Ocean Acidification
Ocean acidification is caused by the increasing levels of carbon dioxide (CO2) in the atmosphere that is then absorbed by the ocean, resulting in a decrease in pH. This decrease in pH is due to the chemical reaction of CO2 with the water molecules in the ocean, forming carbonic acid. There are also human impacts that increase ocean acidification. Things such as human industry, deforestation, and runoff all lead to causing the ocean to be more acidic.
Industry
Due to the Industrial Revolution in the 1800s, the economy shifted from an agrarian economy to one dominated by industry and manufacturing. The way these industrial buildings work and operate is by burning coal or oil, which are known as fossil fuels, the burning of coal or oil creates energy and steam, which powers large turbines, and this is how energy is created. This process is one of the reasons we have an increase in carbon dioxide emissions in our atmosphere.
Deforestation
While the human industry is adding more carbon dioxide into our atmosphere each day, we are also eliminating another one of the primary sources that absorb carbon dioxide. Our forests absorb approximately 2.6 billion tons of carbon dioxide each year, making it about two-thirds of the carbon dioxide produced. Plants and trees take carbon dioxide from the atmosphere and use it for photosynthesis to turn it into organic tissue such as wood and leaves. However, when trees are cut down, the carbon that the trees had uptaken is now released back into our climate.
Runoff
When trees are cut down, and the soil gets displaced, these soils have nutrients and fertilizers that make them acidic, which then get washed away into our oceans. These nutrients then cause an increase in algal growth. Once the algal blooms die off, they consume oxygen and release carbon dioxide into the oceans, leading to the pH of the water dropping even further.
How Ocean Acidification Affects Corals
Being the backbone of so many marine organisms in the oceans is what allows many regions across the globe to harvest fish sustainably. Having a multitude of marine species is what also brings huge economic value to coastal towns and islands through the use of tourism and recreation. Many small island nations depend heavily on reef-based tourism for economic development. The economies of these small islands rely on coral reefs for their economic value because they bring in tourists for different activities such as diving tours and fishing trips. Coral reefs are not only great for providing coastal residents with food and economic value, but they also provide residents with protection from storms. During storms and floods, the reefs act like a barrier from harsh waves, essentially dampening the destruction that would typically occur if the reefs were not there.
How Ocean Acidification Affects Oysters and Clams
Other calciferous organisms, such as oysters and clams, help the ocean out by filtering the water as they search for food. Oysters feed by filtering algae and other particles from the water through the process of filter-feeding they are helping to keep the water clear. Not only do these organisms play several crucial roles in keeping the oceans clean and healthy, but they also play a significant role in our food chain. With each year, the world’s seafood consumption is increasing; however, with the impacts of the oceans becoming more acidic, it is harder for these organisms to survive. With the massive decrease in pH in such a short time, there is a strong possibility that we might see a tremendous dropoff in our shellfish intake if we cannot change our ocean’s pH.
How Ocean Acidification Affects Shrimp and Crabs
Shrimp and crabs can break the materials down to detritus. Then bacteria will reduce the detritus to nutrients. The active role of shrimp and crabs are what helps keep our oceans clean and healthy by removing unwanted matter.
Solutions to Combat Ocean Acidification
Renewable Energy
Renewable energy for fossil fuel burning. Using fossil fuel alternatives such as biomass or geothermal energy would help combat carbon dioxide emissions from 25 to 40 percent.
Industrial Regulations
We can lower carbon dioxide emissions from industrial practices is if we were to regulate how much carbon dioxide an industrial plant can put into the atmosphere. If these actions were to be regulated, we would slowly see our ocean’s pH rise and return to its standard rate.
Lower the Number of Trees Being Cut Down
Another way to combat ocean acidification is if we were to lower the number of trees being cut down, we would be able to have another significant carbon sink source back, which would allow for some of the pressure to be taken off of our oceans and allow them time to recover. Without the continuation of massive forests being cut down, this would also lower the runoff accumulation into our oceans because we would have more roots to hold the soil in place that would otherwise be washed away into the ocean.
Can We Combat Ocean Acidification
If these actions were to start happening in the near future, then over a period of time, we would slowly see our oceans come back to stability and come back to a normal place. We would probably see an increase in the productivity of so many marine species because an acidic ocean affects not just calciferous organisms; it affects every species because all species rely on calcium carbonate organisms in one way or another. The simplest way to stop more carbon dioxide from getting into our oceans is to stop cutting down forests and not run our industrial systems on fossil fuels. However, with the expansion of the human population, doing both of those things seems unrealistic. We are cutting down forests to provide timber for housing or to use the land to give the growing population a place to live. We rely on industrial institutions to manufacture the goods that we need to survive every day. Without the continuous action of these two occurring each day, the human lifestyle would diminish rapidly. So while I think we can lower our human impact on ocean acidification, I truly don’t think we can omit it.
Sources:
Hofmann, G. E., Barry, J. P., Edmunds, P. J., Gates, R. D., Hutchins, D. A., Klinger, T., & Sewell, M. A. (2010). The effect of ocean acidification on calcifying organisms in marine ecosystems: An organism-to-ecosystem perspective. Annual Review of Ecology, Evolution, and Systematics, 41(1), 127–147. https://doi.org/10.1146/annurev.ecolsys.110308.120227
Osterloff, E (n.d.). What is ocean acidification? Natural History Museum. Retrieved September 23, 2022, from https://www.nhm.ac.uk/discover/what-is-ocean-acidification.html.
Prahalad, V., DiMaggio, M., & Manzello, D. P. (2019, July 31). Effects of ocean acidification on marine calcium carbonate: Journal of Emerging Investigators. Effects of Ocean Acidification on Marine Calcium Carbonate | Journal of Emerging Investigators. Retrieved September 20, 2022, from https://emerginginvestigators.org/articles/effects-of-ocean-acidification-on-marine-calcium-carbonate
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