Ocean acidification is an under-publicized topic that is
doing incredible damage to marine ecosystems around the world. The chemistry is
something that is very understood by scientists: as carbon dioxide is pumped
from human activities, it is absorbed by the ocean. To maintain chemical
equilibrium, some of the carbon dioxide reacts with the water to form carbonic
acid. This acid reacts with the water to form bicarbonate ions and hydronium
ions. This increase in ion concentration increases the acidity of the water. In
our oceans from 1751 to 1994, the acidity has increased almost 30%. A change
remotely close to this was about 55 million years ago when “96 percent of all
ocean species went extinct”. This change
causes some major disruptions to organisms including depressing their metabolic
rates, depressing their immune responses, increasing coral bleaching, harming their
reproduction, and disabling shellfish from forming their shells (calcification).
Surprisingly, it also makes sound travel faster and longer, making it much
harder for organisms to hear if they are accustomed to a specific level of
background noise. In a study conducted with the Clownfish , also known as “Nemo”,
as acidity increased, “it became harder for Nemo to avoid predators and harder
for it to find its way back to its home reef.” All of these harmful effects of
ocean acidification come together to result in many populations of species to disappear
from their ecosystems.
In the grand scheme of the food web, ocean acidification has
more immediate effects on smaller organisms. Corals, phytoplankton, mussels,
snails, sea urchins and a whole host of organisms use calcium and carbonate to
build their shells or skeletons. As acidity increases, carbonate availability declines
therefore making it difficult for these organisms to construct their bone structure
and protection. All of these aspects make staying alive almost impossible for
small organisms. Tough luck for the animals that feed on them. For example: “20-40%
of Pink salmon’s diet is comprised of a type of plankton that is expected to disappear
in the next 50 years”. When there is a disruption to any organism that is on a
low trophic level, it will have a lasting impact on each trophic level after
that. If a human’s main source of food was this Pink Salmon, they will have to
change the resources they use to stay alive. Even so, it isn’t just local
fisherman who rely on marine organisms, its huge companies as well. Even
McDonalds had “Fish McBites” made of Alaskan Cod. The Bay Area will especially
feel the hit of ocean acidification. With our giant market of shellfish, the
effects of this problem will take a large toll on what seafood we can eat and
sell.
This disruption will not only have huge impacts on the
resources we take advantage of as food. Humans also know less about the bottom
of the ocean than they do about the moon. “Even though we don’t really know
what’s there, it’s such a mystery and it’s so awesome to think about all these
organisms and ecosystems that are beneath the surface.” Humans have always been
fascinated by exploration and it would be such a shame to lose a whole world that
we haven’t even really discovered yet. This moral aspect to the problem of
ocean acidification of destroying habitats, ecosystems, and diversity is
coupled with an economic aspect. Marine ecosystems are especially economically
productive. Fisheries provide a “source of protein around the world and a major
source of income for fisherman”. Overall, people want to go to the beach to see
clean water, no trash, and healthy animals.
Ocean acidification is occurring and there is nothing we can
do to completely stop it. However, we can curb the output of CO2 to try and
slow the process down. If there is less carbon dioxide in the atmosphere, the
ocean and its natural processes will be able to absorb it at a rate that isn’t
as detrimental to organisms. The “number one thing that the government can do
is to reduce carbon pollution”. The role of the Center for Biological Diversity
comes into play because they work in protecting species by submitting petitions
to place them under the Endangered Species Act. Also, they sue the government
when it fails to meet the expectations of legislation that is already in place.
There needs to be much more serious laws to reduce carbon output. Luckily Obama’s
New Climate Change Plan begins to address the necessity of cutting down
emissions from existing, dirty, power plants. It also promises to provide
subsidies for cleaner technologies. Although climate change is what is being
addressed in Obama’s plan, ocean acidification will be affected as well. Also
known as “Climate Change’s Evil Twin”, ocean acidification needs to be
addressed hand in hand with greenhouse gas pollution.
If you are interested in finding more information about
Jeffers and the Center for Biological Diversity, go to www.biologicaldiversity.org.
-Julia Hansen, EarthScope Reporter
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