Oceanic Hypoxia: EN Research

Oceanic Hypoxia

-          Occurs when the oxygen concentration in the water falls below 2mg/L, the necessary level to sustain most animal life

Eutrophication

-          The addition of excessive amounts of nitrates and phosphates, which when added to a marine environment causes accelerated stimulated plant and algae growth and depletes the normal amount of oxygen necessary for marine life

-          Creates algae blooms which can be deadly to the surrounding plant and animal life

-          Largest eutrophic zones are located around industrialized areas with tons of water pollution each year

Causes of Eutrophication

-          Point Sources

o   Any single identifiable source of pollution from which pollutants are released such as a sewage pipe from an industrial factory

-          Nonpoint Sources

o   Generally caused by runoff from rain and seepage

o   Fertilizers in a high water table zone

Problems Caused

-          decrease in the population of species in hypoxic areas

-          destruction of coral reef ecosystems

-          leads to dead zones where no life can be sustained

-          damages the economic coastal fishing industry

-          lowers the reproductive hormones in male and female fish in hypoxic environments

Ways to Solve

-          addition of aluminum sulfate in the water to decrease levels of phosphates

-          decreasing the amount of point and nonpoint sources of pollution in coastal industrial areas

-          learning eco friendly habits

Internet Sources

http://www.epa.gov/owow/wetlands/pdf/hypoxia_pr.pdf

http://toxics.usgs.gov/definitions/hypoxia.html

http://oceanservice.noaa.gov/products/pubs_hypox.html

http://www.cop.noaa.gov/stressors/pollution/

http://oceanservice.noaa.gov/facts/deadzone.html

http://kodu.ut.ee/~olli/eutr/html/htmlBook_4.html

http://oceanservice.noaa.gov/education/kits/pollution/03pointsource.html

Oceanic Acidification: JA Research

Acid Rain/Ocean Acidification

·      Caused when carbon dioxide, sulfur, or nitrogen combine with seawater

·      Acidification affects the organisms at the bottom of the food chain

o   Sea urchins, coral, plankton

o   Harder to harness calcium carbonate for exoskeleton

·      Increased nitrogen causes algal growth àalgal blooms and eutrophication (low oxygen)

·      Acid rain has largest effects on coastal waters

·      Fossil fuels, farming, raising livestock all create sulfur dioxide, ammonia, and nitrogen oxidesànitric and sulfuric acids

·      Most affected areas: near power plants, eastern North America, Europe, southern and eastern Asia

·      Ocean pH has been lowered by 0.1 since before Industrial Revolution; predicted to decrease another 0.3-.04 by 2100

Woods Hole Oceanographic Institution (2007, September 7). Acid Rain Has A Disproportionate Impact On Coastal Waters. ScienceDaily. Retrieved March 2, 2012, from http://www.sciencedaily.com­ /releases/2007/09/070907175147.htm

·      Acidification affects coral reefs

o   Slows growth of reefs (they need carbonate)

o   Reefs are very important to marine life

·      Reduce CO2 emissions to slow acidification

Natural Resources Defense Council (2009, September 17). Ocean Acidification: The Other CO2 Problem. Natural Resources Defense Council. Retrieved March 2, 2012, from http://www.nrdc.org/oceans/acidification/default.asp

·      Severe acidification happened before (water was so corrosive it ate the shells of animals)

o   Took millions of years to recover

·      Ocean acidifying 10 times faster than 55 million years ago when there was a mass extinction; acidification was 55 million years ago

·      .1 lowering of pH means that ocean has 30 percent more hydrogen atoms than 200 years ago

·      Tests run in labs show that acidification inhibits ability to grow calcium carbonate shellsàruin whole ecosystems

·      Lots of CO2 released into atmosphere 55 million years ago; Paleocene-Eocene thermal maximum, or PETM

o   Caused many deep ocean species to go extinct

o   Ocean bottom turned red because of acidification

·      Acidification happening faster now than before, so more extinctions possible

·      Acid is stronger, so could affect shallow water too

An Ominous Warning on the
Effects of Ocean Acidification. Yale Environment 360. Retrieved March 7, 2012 from http://e360.yale.edu/feature/an_ominous_warning_on_the__effects_of_ocean_acidification/2241/

Oceanic Acidification: RM Research

Ocean Acidification Caused by Atmospheric Carbon Dioxide

            Atmospheric carbon dioxide affects not only the air quality, but also the pH levels of the ocean below it. Specifically, the carbon dioxide makes the ocean water more acidic, resulting in the effect known as ocean acidification. Ocean acidification is detrimental to marine life. Acidification has the greatest effect on corals and plankton. Ocean acidification is important for humans to know about because human made resources are the primary cause for the abundance of carbon dioxide. The loss of marine resources from ocean acidification affects the marine ecosystem adversely.

            Higher acidic levels in the ocean have a degrading affect on the marine life. Most commonly, ocean acidification affects corals both tropical and sub-tropical. Acidic ocean water attacks the coral’s carbonate structure. The carbonate structure gives the coral its support and protection. Without the carbonate shell, the soft, organic part of the coral is left exposed. The soft part is then subject to predation and natural destruction. The elimination of coral can exterminate tropical and sub-tropical reefs. All of the organisms that inhabited the destroyed coral reef lose all forms of shelter and most food sources. The organism either falls subject to predation or starvation as a result of the destruction of a reef. Plankton are also susceptible to ocean acidification. Acidic water breaks down most plankton’s protective carbonate shells. Without the shells, the plankton die, effectively eradicating the food source of many marine organisms. Ocean acidification also has detrimental affects on nearly every organism inhabiting the oceans.

            Ocean acidification is primarily caused by humans. Humans cause ocean acidification by the combustion of fossil fuels that humans use for daily uses. Most humans are responsible for the combustion through a very common method of transportation. Any gasoline-burning vehicle emits carbon dioxide in gaseous from which travels straight into the atmosphere. Factories also burn off an immense amount of fossil fuels leading to direct atmospheric absorption. The main reason for atmospheric carbon dioxide is an increasing earth population combined with a dependence on the burning of fossil fuels to perform ordinary tasks. Burning fossil fuels is an action that can easily be both avoided and prevented by humans. However, the current increasing rate of combustion and carbon dioxide entering the atmosphere only leads to the prediction that the ocean will continue to get more acidic.

            Ocean acidification has a detrimental effect on the oceans that humans take for granted today. The acidification primarily affects corals and planktons, but can have effects through the entire marine ecosystem. The main cause of ocean acidification is oceanic absorption of atmospheric carbon dioxide. The carbon dioxide is a direct result of the combustion of fossil fuel, which humans are increasingly burning. As fossil fuels are increasingly used, Ocean acidification may destroy the world’s oceans as they are known today.

Works Cited

The Royal Society, Science Policy Section. (2005). Ocean acidification due to increasing atmospheric carbon dioxide. Cardiff: Clyvedon Press Ltd.