Date: October Essential Question: How are humans affecting our world s oceans and what other factors are involved?

Transcription

1 Cornell Notes Lecture, reading/chapter/novel/article during class, power point, movies (if need to collect info.) Topic:_Oceans in Jeopardy Name: Mrs. Stahl Class: Marine Science Honors Period: F Date: October 2015 Essential Question: How are humans affecting our world s oceans and what other factors are involved? Questions/Main Ideas: What does the word pollution mean to you? Notes: Trash, sewage, chemicals, oil spills, high nitrogen levels, runoff, PCB s, DDT s, destroyed food webs. What are the major threats to oceans and wildlife? Pollution Climate Change Seafood farming Overfishing Invasive species Coastal development Fishing damage Seafloor damage POLLUTION A. Ocean Dumping Humans use the ocean as a dumping site Trash Plastics How does plastic harm marine animals? In 2007, Coastal Clean-up cleaned up 6 million pounds of debris. 1.3 million cigarette butts 349,143 glass bottles 308,292 metal cans 6,435 syringes 61% of the trash was plastic 235 animals were found in trapped debris -Estimated that naval and merchant ships legally dump 77 tons of plastic annually ,000 tons of fishing nets, ropes, traps, and buoys = 2,600 tons of plastic packaging. - 1 million tons of plastic waste enters the ocean annually. Enters by wind, being dumped by boats, and being flushed into drains. - Some scientists consider plastic trash to be as harmful as oil spills and toxic chemicals. -One plastic six pack ring = 450 years to break down. - Mostly endanger larger animals and birds. - 30,000 fur seals killed annually (estimated) - Discarded nets harm fish and turtles. - Shellfish traps left unmanaged trap and kill animals = starvation. - Florida: 100,000 traps set, 25,000 lost - Whales and dolphins are suffocated by plastic bags. - Birds are entangled by fishing line. - Sea turtles eat plastic bags because they resemble jellies.

2 Photodegrade Commercial Dumping Military hardware and munitions Radioactive Waste - The plastics do not get digested, but they block the digestive tract and cause the animals to starve. Plastics are broken down slowly by radiant energy which causes the plastics to turn into microscopic plastic particles that smaller organisms will ingest. Toxic substances that are not only harmful but also demand a lot of oxygen. The decomposition of these materials by microorganisms tends to deplete the water of oxygen. Upwelling brings up all of the toxic substances to the surface = kills shallow water species. -WW II: toxic gases and chemicals removed from Germany were dumped in the N. Atlantic. In the Pacific trucks, tanks, etc. were dumped. - Vietnam War: vehicles and munitions were dumped off of Southeast Asia. - Gulf War: munitions and hardware were dumped into the Arabian Gulf. -It can poison marine life but the metal can also create artificial reefs. Electronic, chemical, and defense industries and nuclear facilities produce large amounts of highly toxic / radioactive waste that is kept above ground in repositories or landfills. They want to dump it into the deep sea at subduction zones around trenches sucked back into the mantle eliminating the problem. What happens if they rupture? Urban Pollution Surface runoff from cities Pesticides Fertilizers Chemicals from oil and gasoline Residue from industry Bacteria from raw sewage All drains really do lead to the ocean! Pesticides and Toxic Materials -Everything we do on land directly influences the ocean. -Damages recreational areas as well as coastal fisheries. -Chlorine added to drinking water and then later to sewage during treatment forms chlorinated organic compounds in seawater that are toxic to some marine organisms. -Dichlorodiphenyltrichloroethane, DDT -Polychlorinated Biphenyls, PCB s -Mercury, lead, zinc, chromium - DDT was suspended in the 1960 s. -DDT and PCB s stay concentrated in the ocean for long periods of time. - DDT carried by runoff from land. -DDT was banned and another pesticide was created called dicfol- it still contained 1-7% of DDT and was used until 1988.

3 PCB s Biological Magnification -Birds were feeding on fish that were contaminated and the birds were laying eggs with really thin shells. When the parents sat on them they would break. -This decreased brown pelicans and bald eagle populations. Plastics, solvents, electrical insulators= enter the atmosphere via precipitation. Some particles do not dissolve in water but are absorbed by suspended particles of clay and detritus. They clump together and sink to the bottom. DDT and PCB s get concentrated in the sediment and it moves up the food chain, starting with phytoplankton. Organisms can t break them down so they become concentrated in their tissues. The concentration can become so high that organisms will feed on the contaminated flesh and die , Minamata, Japan: dumped waste into the bay that had high amounts of mercury, which formed organic complexes and entered the food chain (shellfish and fish). Severe mercury poisoning and death resulted. It also caused damaged nervous system in young kids (if there mom ate fish while she was pregnant it was worse). Plankton and toxic compounds Air Pollution Human Waste Eutrophication Agricultural Waste Petroleum Pollution Phytoplanktons are susceptible because they are the base of the food web. Zooplankton then eats the phytoplankton, and then larger animals eat like crustaceans, fish, sharks, and humans. The toxic compounds interferes with cell division, this is not well studied. Increased pollution in the N. Atlantic = decreased phytoplankton and zooplankton numbers. Burning of fossil fuels CO 2 released and sulfur dioxide= dissolve into the water and enter the ocean = acidic water. -Reduce water quality by adding harmful microorganisms and nutrients. - Clams, mussels, oysters filter large amounts of microbes such as hepatitis and salmonella-meat can be unfit to eat. - Coliform bacteria: found in animal intestines and are a great indicator as to how much waste is entering the water. -Raw and treated sewage adds large amounts of nutrients; nitrates, ammonia, and urea = algal blooms. - Increased phytoplankton makes the water turbid and hinders primary production in the deeper waters. - Phytoplankton dies and gets decomposed by aerobic bacteria, decreases oxygen, kills organisms, releases hydrogen sulfide (harmful), and more death occurs. Fertilizer and animal waste. Continual runoff= hypoxic zones (abnormally low oxygen levels). -High demand - Released through runoff, industrial discharge, offshore drilling accidents, cargo ship accidents that transport oil, etc.

4 Where does the oil go, what does it do? Petroleum Products: Crude oil (mixture of 10,000 different chemical compounds) = most of the compounds are organic molecules / carbon based. -Two major types are aromatic hydrocarbons (form ring structures) and aliphatic hydrocarbons (straight chains). -Spreads like a film on the surface - Lighter components evaporate -Absorbed by clay / sediment and taken to the bottom. - Bacteria can digest simple oil / smaller molecules. - Larger molecules create what s called tarry chunks where they float on the surface or lay on the bottom. -We don t know how oil affects deep sea organisms. -Suffocates upper level organisms. - Refined petroleum such as gasoline and kerosene are more toxic than crude oil. Oil Spills Thousands occur each year Ecological Effects of Oil Spills Oil Spill Clean-up Climate Change Increased carbon dioxide levels Largest in the U.S. 1. Deepwater Horizon / BP MC252 on April 20, An estimated 134 million gallons went into the Gulf of Mexico. The oil seeped out for 89 days at a depth of 5,000 ft. The depth and volume made it really hard to contain. 2. Ixtoc-1, 1979 in the Gulf of Mexico: 126 million gallons of oil. 3. Exxon Valdez in Alaska, 10.8 million gallons of oil. -Birds / Mammals: oil coats bird wings, swallow it, weighs them down, etc. -In cold weather, one drop of oil can cause hypothermia in animals. -Example- Sea otters: oil blocks the animal s natural ability to insulate itself. Clogs ears, nostrils, and irritate the eyes. Some sources say it can cause cancer in otters. - Invertebrates and Algae: Less visible. Sandy habitats: oil seeps into the spaces between the sand, which kills the crabs and organisms living in and between the grains. Bivalves: flesh becomes contaminated and passed up the food web. Molluscs: oil is a narcotic and causes the animals to lose their hold and the tides take them away. -Oil booms - Oil skimmers - Straw: collect and burn. Then it goes into the air. - Genetically engineered bacteria: breaks down / degrades most of the crude oil (organic compounds). -Naturally occurring bacteria that live near the seeps. -Last 100 years temperatures have increased..74 C (1.33. F) -Example: Glaciers freeze at 32 F (0 C), melt at 33 F, therefore if the temperature is at 33 F, then they are slowly melting. -Increased sea temperatures: alter distribution and diversity of species, oxygen levels, coral reef health, and wind / rainfall patterns. Species distribution: Water temperatures are causing animals to move into areas they wouldn t normally go. Example: Venus clam and Eastern oyster: warm water heads north, therefore they are expanding, which results in competition with the

5 native species. From there diseases are spread and native species can be driven to extinction. Water temperature and fishes: Alters spawning, growth rates, larval survival, food availability, and disrupts weather fronts. Oxygen levels: Increase in temperature, decreases the amount of oxygen in the water. Warmer temperatures also increase metabolism, which increases oxygen need. Coral Reefs: coral bleaching (stress, which increases diseases). Corals lose their zoozanthellae (60-90%) and they look pale because the calcareous skeleton shows through the now translucent tissues. Melting glaciers also raises sea levels because more freshwater is added. The increase in sea level could be devastating for corals because they won t receive adequate sunlight. Rainfall and Wind: El Nino = Pacific= changes ocean current patterns, decreases productivity, and decreases marine organisms. The more rainfall, the more acid rain and the more freshwater added to our oceans, which will decrease salinity and stress marine organisms out. Increased wind along coastlines increases upwelling and changes currents. When the currents are changed the larvae won t be properly dispersed. Increased upwelling also increase productivity because it mixes up the nutrients from the bottom and brings them to the top. However, this may seem good, but it increases the productivity too much leading to an anoxic event = mass killings Also disrupts food, distribution, and increases death. Nonnative Species Also known as alien or exotic. Organisms that have been introduced or intentionally placed into a region / body of water. Ships Ballast: Ballast: compartment within a ship that holds water. Back in the day rocks were commonly used and they would take them from the shoreline. The rocks would contain little organisms on them and when they reached their destination (ports) they would change the rocks out and discharge the water. Ex: European green crab: voracious predator that feeds on native clams, oysters, snails, and other crabs (Delaware -> Nova Scotia).

6 Aquaculture: Humans raise nonnative species and then release themcompeting with native species as well as introducing disease. Ex: 1970 s Eucheuma (alga) was imported from the Philippines to Hawaii for studying purposes (looking at using it for a food additive called carrageenan). Most widely farmed seaweed and had taken over the fringe reef where it smothers and kills coral. They have been trying to clean it up with a large vacuum cleaner that sucks up 159 pounds an hour. Accidental Introduction: Venomous lionfish (native to the Indo-Pacific) are residing in the coral, rocky, and artificial reefs along the SE coast of the US and Bahamas. Coastal Development Destruction of Habitats They were accidently added into our ecosystems during Hurricane Andrew. In 1992 an aquaria shattered and six lionfish spilled into Biscayne Bay (Miami). In 2008, they were found in N.C., Florida, Caribbean, and as far south as Cuba. They are beautiful but they have no natural predators and they compete with local species for resources. They also prey on young species. Wetlands / Seagrasses: they are crucial habitats for juvenile organisms. They act as a nursery, providing critical nutrients, shelter, and spawning grounds. These habitats make up most of the brackish estuary. About 80% of all juvenile organisms grow up in estuaries. Industrial and residential development and dredging channels are the altering these habitats. Beaches: Vacation spots, retirement, recreational fun, and lots of hotels along the shoreline. Causes a decrease in animal populations and disturbs animal nesting sites (birds, horseshoe crabs, and turtles). People ride dune buggies, bring pets, lay in the sun, leave their trash, and disturb the animals. Building beach front homes, docks, and seawalls really disrupts habitats. Beach Erosion: Development of beaches decreases sand dunes and vegetation. Each year hundreds of thousands of dollars are spent restoring the beaches that were destroyed the year before. Damming rivers: prevents natural erosion from occurring. Breakwater and jetties in coastal zones also produce changes in beaches, preventing longshore currents from occurring.

7