Resources from the Ocean and Ocean Pollution

Living Resources Fishing the ocean almost 75 million tons are harvested each year Overfishing has become a problem: Orange Roughy, Rock fish, Swordfish, Blue Fin Tuna Drift nets make it easy to overfish. Drift netting is a fishing technique where nets, called drift nets, hang vertically in the water column without being anchored to the bottom. The nets are kept vertical in the water by floats attached to a rope along the top of the net and weights attached to another rope along the bottom of the net.

Dolphin free tuna. Drift nets are not very selective. Dolphins would accidently get caught in drift nets and drown. This is known as by- catch. Dolphins would drown and be ground up as part of the “tuna.” United Nations have banned drift nets, but some countries are still using them illegally.

Living Resources Farming the Ocean- many people raise ocean fish in fish farms to help meet fish demand. It requires several holding ponds which contain fish at a certain level of development. When the fish are old enough, they are harvested. Examples are shrimp, oysters, crabs, mussels.

Seaweed Species of algae An example would be kelp Grows 33 cm a day High in protein Used as a thickener in ice cream, jellies Some ice creams contain Carageenen as a thickening agent (it's an extract from kelp) Used in sushi and other dishes

Nonliving resources Oil and natural gas Fresh water and desalination Desalination is the process of removing salt from seawater. Not as simple as it sounds and is very expensive. ( million)Saudi Arabia has one of the largest desalination plants in the world. 250 are in USA; Florida, California, and Texas

Seafloor minerals Nodules on ocean floor are made mainly of manganese which can make steel. Some also contain iron, phosphates, nickel, Copper and cobalt. Estimate 15% of ocean floor is covered Nodules are formed when dissolved substances in sea water stick to solid objects like pebbles. Located in deepest parts, dangerous and expensive

Tidal energy- renewable source of energy using ocean tides. Areas must have a coastline with shallow narrow channels like Cook Inlet in Alaska Wave energy- renewable source of energy using waves. North Sea waves are strong enough to produce power in parts of Scotland and England Energy

Tidal energy Renewable energy that uses tides, must have a coast line that has shallow and narrow channels like Cook Inlet in Alaska.

Wave Energy Renewable energy that uses waves. Must have strong waves like the North Sea which can produce energy for parts of Scotland and England.

Trash Dumping 1980’s hospital trash was an issue- needles, vials of blood etc where landing on beaches. Hospitals produce 3 million tons of medical waste a year. Most are now buried in sanitary landfills. Marine animals mistake plastics for food and get tangled in it, choke etc.

Sludge Dumping By 1990, the US alone had discharged 38 trillion liters of treated sludge along it’s coast Raw sewage is all the stuff that is flushed or goes down your drains. Once it reaches the sewage treatment plants and is treated; the solid portion is called sludge. Many communities dump it in the ocean where it can be stirred up by currents or storms and pollute beaches.

Oil Spills Large tankers transport billions of barrels of oil across oceans. An example of an oil spill was the Exxon Valdez in 1989 off the Coast of Prince William Sound Alaska. Enough oil to fill 125 Olympic sized swimming pools. 2.1 billion to clean up. Effects of any oil spill can both environmental and economic effects. Economically- tourism(hotels, restaurants, shops etc), commercial fishing industry- people’s jobs in these areas are lost or have less income which means they have less money to spend, which effects other areas in the community.

Oil spill cont. Animals are hurt- breeding grounds are ruined. Spilled oil can harm living things because its chemical constituents are poisonous. This can affect organisms both from internal exposure to oil through ingestion or inhalation and from external exposure through skin and eye irritation. Oil can also smother some small species of fish or invertebrates and coat feathers and fur, reducing birds' and mammals' ability to maintain their body temperatures. Since most oils float, the creatures most affected by oil are animals like sea otters and seabirds that are found on the sea surface or on shorelines if the oil comes ashore. During most oil spills, seabirds are harmed and killed in greater numbers than other kinds of creatures. Sea otters can easily be harmed by oil, since their ability to stay warm depends on their fur remaining cleanseabirds

Oil coated birds' feathersOil coated birds' feathers, causing birds to lose their buoyancy and the ability to regulate body temperature. Mammals could have ingested oil, which causes ulcers and internal bleeding. Sea turtles were covered in oil Dead and dying deep sea corals were discovered seven miles from the Deepwater Horizon well. Mammals could have ingested oil Sea turtles were covered in oil Dead and dying deep sea corals

Cleaning up the oil spill Containment and recovery equipment includes a variety of booms, barriers, and skimmers, as well as natural and synthetic sorbent materials. Mechanical containment is used to capture and store the spilled oil until it can be disposed of properly.boomsskimmerssorbent materials Dispersing agents, also called dispersants, are chemicals that contain surfactants and/or solvent compounds that act to break petroleum oil into small droplets. In an oil spill, these droplets disperse into the water where they are subjected to natural processes, such as waves and currents, which help to break them down further.

Double hulled tankers-the inner hull prevents oil from spilling into the ocean if the outer hull of the ship is damaged.