Geography and Oceanography - Chapter 26 pot

Ocean Uses and Human Impacts Outline • Marine Resources • Mariculture • Drugs • Marine pollution • Invasive species • Climate Change Classes of Marine Resources Physical resources Mineral deposits, petroleum, natural gas, freshwater Biological resources Plants and animals, microbes Marine energy resources Energy from heat or motion of water Non-extractive resources Transportation, recreation, waste disposal Petroleum and Natural Gas Oil and gas are often found together beneath impermeable caprock. Drilling for oil offshore requires specialized equipment and is more costly than drilling on land. Gulf of Mexico Oil Spill 5000 barrels/day  15000 barrels/day Containment (booms), skimming, dispersants, Domes, caps, siphons, new well Full recovery will take many years Salts and Minerals • Magnesium • Sodium chloride • Manganese nodules • Phosphorite • Metallic sulfides and muds Fresh Water • Only 0.071% of Earth’s water is liquid, fresh, and available at the surface for humans • More than 1500 desalination plants worldwide • 3.5 billion gallons/day, and rising! Marine Energy – Wave Motion Energy generated by waves (Dr Brekken) and tides Biological Resources Major types of commercially harvested fishes, crustaceans, and mollusks Biological Resources World Commercial Catch of Marine Fishes, Crustaceans, and Mollusks, by Species Group, 1997 Species Group Millions of Metric Tons Herring, sardines, anchovies 21.5 Jacks, mullets, sauries 10.9 Mollusks 15.5 Cods, hakes, haddocks 10.2 Redfish, basses, conger eels 7.4 Crustaceans 6.8 Tunas, bonitos, billfishes 4.8 Mackerel, snooks, cutlass fishes 5.2 Flounders, halibuts, soles 1.0 Miscellaneous Marine Fishes 17.5 Total for all sources 100.8 Table from Garrison, 4ed [...]... http://www.mbayaq.org/cr/seafoodwatch.asp  See also:  http://www.seafoodinfocenter.org/search.html  http://www.seafoodchoices.net/ Potential Harmful Impacts of Mariculture  Escape of nonnative species  Herbicides  Disease tolerance and spread  Nutrient enrichment -> eutrophication Drugs • Researchers estimate that 10% of marine species may contain useful medical compounds • Acyclovir, the first... bone Marine Pollution - DDT  Levels of organic pollutants may be low, but biological amplification concentrates harmful toxins  The concentration of DDT in the fatty tissues of organisms was amplified up to 10 million times in a food chain off the coast of New Jersey Marine Pollution – HABs and Anoxia Invasive Species  Introduced species crowd out native species, alter habitats, and impose economic... exponentially over the past 200 years and shows no sign of leveling off  More than 175 species of introduced marine invertebrates, fish, algae, and higher plants live in San Francisco Bay  http://www.invasivespecies.gov/ Invasive Species – Zebra Mussel Recent US Bioinvasions http://www.pewoceans.org/reports/introduced_species.pdf Global Warming Arctic Ocean and Sea Ice Mountain Glacier Retreat 1858... http://www.pewoceans.org/reports/introduced_species.pdf Global Warming Arctic Ocean and Sea Ice Mountain Glacier Retreat 1858 2001 “The Snows of Kilimanjaro”?? Antarctic Ice Sheet Antarctic Ice Sheet EAIS WAIS Both Greenland Ice Sheet and West Antarctic Ice Sheet = 6 m global sea level 25% of U.S population lives within 10 m of sea level WAIS People at risk  Country population Bangladesh 115 million Egypt 55 million Indonesia...Fisheries Typical evolution of ocean fisheries Fisheries Exploitation Concept of a Stock A population of a species of fish that is reproductively isolated in space and time Each stock must be treated separately in assessing fishing impacts Stock Equilibrium Growth Recruitment Stock Size (Exploitable Biomass) Mortality Fishing Removals These four factors must remain . resources Plants and animals, microbes Marine energy resources Energy from heat or motion of water Non-extractive resources Transportation, recreation, waste disposal Petroleum and Natural Gas Oil and gas. also:  http://www.seafoodinfocenter.org/search.html  http://www.seafoodchoices.net/ Potential Harmful Impacts of Mariculture  Escape of non- native species  Herbicides  Disease tolerance and spread  Nutrient enrichment -& gt; eutrophication Drugs • Researchers. gallons/day, and rising! Marine Energy – Wave Motion Energy generated by waves (Dr Brekken) and tides Biological Resources Major types of commercially harvested fishes, crustaceans, and mollusks Biological