PDS AP Environmental Science 5th Period 2010-11

In class yesterday we learned about the worst oil spill in the United States until last summer, the Exxon Valdez.

Exxon Valdez (1989)

History: In 1989 Mr. Hazelwood was drunk driving a huge ship in Alaska named the Valdez, which was carrying oil for the company Exxon. The ship collided with some coral and since it was only single hulled, it caused a huge hole in the ship spilling oil. An estimated 257,000 barrels of oil was released into the ocean.

Impact: The oil had a negative effect on the Alaskan wildlife. For birds, the oil weighed down their feathers, making it impossible f0r them to fly and insulate themselves. Birds that did not freeze to death died because they ingested the oil trying to clean it off. The sea

otters that lived in the area were in jeopardy as

well; oil also destroyed their insulation and it caused damage totheir eyes, lungs, and intestines.

Clean Up Methods: The Coast Guard uses physical, chemical, and biological remedies to get rid of an oil spill

Physical:

Skimmers:  Since oil is less dense than water, they could skim the oil off the surface of the water using skimmers

Booms: Booms corral oil, not allowing it to spread out and making it easier to skim

Chemical:

Dispersants: dispersants are oil solvents that can break it down into smaller parts, giving it more surface area so that the natural bacteria in the ocean can help get rid of it faster

Biological:

Bioremediation: bioremediation is when scientists use a ‘fertilizer’ to force the natural bacteria in the environment to reproduce, resulting in a larger population that can clean up the oil

Bioremediation in Alaska

Comparison to BP Spill: The spill last summer in the Gulf of Mexico was not caused by an oil tanker, but by an explosion in a drilling rig, which was about a mile underwater. This made it harder to stop the oil from leaking into the ocean. By the time they finally could, around 4.9 millions barrels of oil had been released in the Gulf of Mexico, almost ten times more oil than the Exxon Valdez.

Gulf of Mexico Oil Spill (2010)

Sources of Petroleum Input in Oceans Each Year on Average (Metric Tons):

1. Natural Seeps (600,000)

2.Consumption (480,000)

3. Transport (150,000) – Valdez incident

4. Extraction(38,000) – BP incident

Legislation:Response to the Valdez

Oil Pollution Act (1990) – requires oil companies to have double hulled boats, and requires companies to pay a fine for the damage as well as pay for the clean up.

Sources:

Exxon Valdez: http://news.nationalgeographic.com/news/2009/03/photogalleries/exxon-valdez-anniversary/images/primary/090323-03-valdez-tanker_big.jpg

Bioremediation:

http://www.alaska-in-pictures.com/data/media/17/bioremediation-project_3253.jpg

Gulf Oil Spill:

http://www.sevensidedcube.net/wp-content/uploads/oil6.jpg

In class on Tuesday we learned about species populations. A population is a group of individuals of a species that live in a particular area. Populations coevolve based off of the five relationships we learned about in the previous unit (mutualism, comensalism, parasitism, predation, and competition). All populations of any species contain these five characterisitics:

1. Size: Population sizes increase, decrease, or are stable, and  follow patterns

Equation: (Births + Immigration) – (Deaths + Emigration) = Change in size

2. Density: The number of individuals per unit of area

Increase in Density-

Pros: acccess to mates increases, safety increases

Cons: intraspecific competition increases, rescources decrease, predation increases, rate of infectious disease  spreading increases

3. Distribution:

1-Clumped Distribution:herds, school of fish, humans(urbanization)

2-Uniformed Distribution: organisims evenly spaced

3-Random Distribution: trees (seed travel)

4. Age/Sex Stucture:

Sex Ratio-porportion of males to females

Age Structure-describes relative numbers of organisms of each age within a population

Age Structure Diagram

5. Growth Rate:

-annual growth in percentage form

-grows exponentially, yet with limits, which is why graphs have a logistic growth   curve

- all populations have theoretical limit (carrying capacity)

Growth Rate Graph

Age Structure Diagram: http://images-mediawiki-sites.thefullwiki.org/08/3/8/3/25099082503828593.png

Growth Rate Graph:

http://www.cdli.ca/courses/biol2201/unit04_org01_ilo02/BI300002.gif

hey guys so I know that parasitism is when one organism attaches itself to another organism and feeds off its nutrients. One example we used was the deer and hook worm, but the deer wasn’t that effected by the hook worm. How is that different than commensalism?

hi so i wasnt here friday either and i dont really understand the whole Voluntary Cooperation, Government Regulation, and Privitization thing. I understand what each one means, but I was wondering if there was a way to use all three at the same time? like is there some kind of limit to how much the goverment can regulate on private land as opposed to public? The essay link from that class day didn’t really answer the question for me. Thanks

I think that the biggest environmental problem is the melting of the polar ice caps. This problem can lead to the destruction of habitats for many arctic animals, such as the polar bears, penguins, and seals. Also, it will cause our ocean water levels to rise all over the world, creating new shorelines and ending life as we know it.