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Exit Choose to view chapter section with a click on the section heading. ►Resource ClassificationResource Classification ►Nonrenewable ResourcesNonrenewable.

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Presentation on theme: "Exit Choose to view chapter section with a click on the section heading. ►Resource ClassificationResource Classification ►Nonrenewable ResourcesNonrenewable."— Presentation transcript:

1 Exit Choose to view chapter section with a click on the section heading. ►Resource ClassificationResource Classification ►Nonrenewable ResourcesNonrenewable Resources ►Renewable ResourcesRenewable Resources ►Biological Resources – Marine MammalsBiological Resources – Marine Mammals ►Biological Resources – Algae, Aquaculture and MedicineBiological Resources – Algae, Aquaculture and Medicine ►Biological Resources – FishBiological Resources – Fish ►The State of the World’s Fisheries – A Bleak PictureThe State of the World’s Fisheries – A Bleak Picture ►Commercial FishingCommercial Fishing ►Who Owns the Sea?Who Owns the Sea? ►Biodiversity and the FutureBiodiversity and the Future Chapter Topic Menu

2 MenuPreviousNext Resource Classification nAll resources have political and environmental significance because they all have economic value. nTwo common categories for classifying marine resources are:  Renewable and… nRenewable resources are those that growing organisms, sunlight, or other processes naturally replace.  …Nonrenewable Resources nNonrenewable resources are those that natural processes don’t replace, or that do so at such a slow rate that they are not replenished in a human lifespan.  Physical and… nPhysical resources don’t involve biological processes. They include minerals, energy production, and recreation.  …Biological Resources nBiological resources involve bioproductivity, such as fisheries and kelp harvesting. nMost marine biological resources are potentially renewable, but some are not. It happens when a fishery takes a species from the ocean faster than it can reproduce and maintain its population. Whaling is an example of this. Resource Classification Chapter 15 Pages 15-3 & 15-4

3 MenuPreviousNext Energy nAmong the physical marine resources, petroleum and natural gas are the most important to economic contribution. About one third of the world’s crude oil and about a quarter of the natural gas comes from the sea.  Petroleum and natural gas form from the remains of primarily marine organisms, such as plankton and soft-bodied benthic organisms. nSeismic instruments are used to help find oil and natural gas.  Physical characteristics of the rock surrounding oil and natural gas are important. This determines where the oil or gas collects.  Source rock is where hydrocarbons originate, and collect in the spaces underneath reserve rock. This is called an oil or gas reserve.  Sound waves detect the oil and natural gas reserves as low-density pockets in the reserve rock. Nonrenewable Resources Chapter 15 Pages 15-5 to 8

4 MenuPreviousNext Energy (continued) nOil companies use platforms to drill from to extract oil and gas by drilling through sediment and rock into the reserves.  Special drilling equipment is used to minimize the risk of an oil spill or gas leak. nMethane hydrates are ice crystals containing methane found on the continental slope.  The unusual hydrocarbon deposits consist of frozen water molecules that create a “cage” within sediment. Each “cage” holds a single methane gas molecule.  They are another form of non-renewable hydrocarbon. nThey are not currently used as an energy source because it is very expensive to recover them and they are relatively dangerous to handle.  Technologies for handling methane hydrates are in development. Nonrenewable Resources Chapter 15 Pages 15-8 & 15-9

5 MenuPreviousNext Salts and Minerals nFerromanganese Nodules - Nodules are rich in copper, nickel and cobalt as well as iron and manganese.  This makes ferromanganese nodules tremendously valuable. Unfortunately, the cost of recovery at present exceeds the worth of the minerals. nMagnesium Compounds - About half the worldwide magnesium production comes from seawater.  Magnesium is the third most abundant element dissolved in seawater. It occurs as magnesium chloride and magnesium sulfate. nSalts - Evaporites are the salts left behind when seawater evaporates.  Manufacturers use evaporites in the production of fertilizers, medicines, wallboard, other building materials, and table salt. Table salt in turn is used for snow and ice removal, water softeners, agriculture and food processing. Nonrenewable Resources Chapter 15 Pages to 15-13

6 MenuPreviousNext Salts and Minerals (continued) nPhosphorite - Phosphorite or phosphate rock deposits are the remains of marine organisms that live in areas with extensive upwelling. Offshore phosphorite deposits are currently uneconomical to exploit.  Today terrestrial sources are mined. It is estimated these deposits may be depleted by the mid 21st century. To avert a crisis in agriculture/industry, offshore deposits may be important. nMarine Muds and Metals - Hydrothermal vent seawater carries large quantities of dissolved metals and minerals including zinc, iron, copper, lead, silver, cadmium and sulfur.  In the Red Sea are hot brines producing muds rich in metal sulfides, silicate, and other oxides in a high enough concentration to make recovering them economically feasible.  Seamounts are potential resources, in particular cobalt deposits. Nonrenewable Resources Chapter 15 Pages to 15-13

7 MenuPreviousNext Gravel and Sand nSand and gravel are important marine resources. They are second to gas and oil in terms of their annual economic value. nEach year industry mines more than one billion metric tons of sand and gravel from offshore deposits. Nonrenewable Resources Chapter 15 Page 15-13

8 MenuPreviousNext Energy nThe sea provides several types of renewable energy for human use:  1. Wave action accounts for two methods: n1. Building a caisson with an opening under water that permits waves to enter and compress air in the chamber forcing it through a turbine to generate electricity. n2. Placing a series of buoys that rise and fall in the waves cranking a wheel in a circle. An axle coming off the wheel turns a generator.  2. Tides can be be used for energy where tidal change is 3 meters(10 feet) or more. As the tide flows in and out of two way dams, its energy is used to turn turbine generators. One in France produces 500 kilowatts yearly.  3. Warm surface water is used by Ocean Thermal Energy Conversion (OTEC) to vaporize liquid ammonia which in turn drives a turbine. Water is piped back to the deep sea. nOf the three, the most feasible appears to be harnessing wave energy. Renewable Resources Chapter 15 Pages & 15-16

9 MenuPreviousNext Fresh Water nThe single most important factor determining how many people can live in a given area is the availability of fresh water. Human population is rising, and the demand for fresh water with it. The supply isn’t keeping pace, making this resource a growing concern as we move through this century. nDesalinization – getting fresh from seawater – involves removing dissolved salts. Currently there are more than 7,500 desalinization plants worldwide, 60% of which are in the Middle East. The Western Hemisphere accounts for only 12% of the fresh water produced by desalinization.  Recovery methods include: nBoiling seawater - capturing and condensing water vapor. nFreezing seawater - salt is left behind and fresh water is produced. nReverse osmosis - forcing seawater through a semipermeable membrane under pressure letting the water through, but holding back the salt. nCovering large shallow pools of seawater with plastic and recovering the condensation that forms underneath the covers. nOne bottled water company even melts icebergs on special barges to get fresh water. Renewable Resources Chapter 15 Pages & 15-18

10 MenuPreviousNext Nonextractive Resources nYou may not think of these as resources, but they are. Nonextractive resources are those we obtain from the sea without removing anything from the sea. The two most conspicuous of these are sea transport shipping and recreation.  After WW II, the invention of the cargo container revolutionized sea transport shipping. Standardized cargo containers made it possible to quickly load and unload ships. Modern ships can hold more than 4,000 containers.  Ecotourism focuses on visiting and experiencing natural environments and wildlife. Much of it is on or near the sea. nOn the positive side, in a growing number of destinations local people are realizing that they need to preserve the local environments. nOn the negative side, some areas have trouble keeping pace ith the rising number of tourists. Construction and traffic are putting strain on the areas’ ecology. Something seemingly as harmless as feeding fish can change wildlife behaviors. Renewable Resources Chapter 15 Pages to 15-20

11 MenuPreviousNext Whales nUntil 1868, primitive technology made whaling dangerous and difficult.  With the crude methods of harpoon and longshore boats, comparatively few whales could be taken and whale populations remained stable.  Everything changed in 1868 with the invention of the modern harpoon gun. nWhale populations have declined drastically during the 20th century.  International whaling has been so successful that from an estimated whale population of 4.4 million in 1900, today the estimated population is around 1 million. nIn 1982, the International Whaling Commission (IWC) called for an indefinite moratorium on commercial whaling that became effective in  The gray, blue and humpback whales seem to be on the rise in the Pacific.  Unfortunately, the right and southern blue whales in the North Atlantic appear to still be declining. Biological Resources – Marine Mammals Chapter 15 Pages & 15-22

12 MenuPreviousNext Whales (continued) nWhaling continues despite the moratorium for several reasons:  IWC is a voluntary organization and even members don’t have to abide by its rulings.  Whaling continues with the IWC’s allowance for aboriginal hunting to preserve their cultural traditions. Often the “traditions” are carried out with modern equipment.  Another exemption is for scientific whaling. Allowing whales to be taken as specimens for study. Japan, in particular, continues to hunt whales using this clause with their government authorizing 400 whale kills annually. These “specimens” are sold to wholesalers and used as food in school lunches. Other Cetaceans nSeveral small cetaceans are not protected under the moratorium:  Dolphins have become the most endangered of the cetacean. They and small whales are a by-catch problem in tuna fishing.  Many countries eat dolphin. “Dolphin” on a menu in the US is a mahi-mahi fish. “Dolphin” in Peru is dolphin. Biological Resources – Marine Mammals Chapter 15 Pages to 15-24

13 MenuPreviousNext Seals and Sea Lions nHistorically, seals and sea lions have been biological resources exploited for their fur and for food.  Although the marine mammal fur trade no longer exists in the US due to the Marine Mammal Protection Act and consumer pressure, worldwide up to half a million of these seals and sea lions die for their fur annually.  World opposition continues to pressure Canada to ban the harp seal hunt for the pups’ fur. The killing of harp seal pups continues. So public opposition will continue, if for no other reason than that many consider it offensive to exploit these harmless and appealing pups. Biological Resources – Marine Mammals Chapter 15 Pages & 15-25

14 MenuPreviousNext Algae nMarine algae is another resource used as food.  Annually, the Japanese consume nearly 150,000 tons of red algae nori. nThe commercial product algin, which comes from the mucus in kelp and other marine algae, is useful in food processing and other applications.  Algin is used as a food source in salad dressing, ice cream and is used to clarify beer and wine. It is also used in paint and abrasives. nThe industry uses nearly $250 million worth of algin annually. Farming the Sea nThe growth trend in aquaculture is steeply upward. Currently it is growing three times faster than livestock production on land and may exceed it in the next decade. nToday about 25%-30% of the world’s seafood comes from aquaculture. Biological Resources – Algae, Aquaculture and Medicine Chapter 15 Pages & 15-27

15 MenuPreviousNext Farming the Sea (continued) nThere are problems with farming the sea:  Aquaculture also has problems similar to raising livestock on land. nSome farmed fish species take fish to feed them – salmon for example. nKeeping many animals in close quarters tends to allow disease to spread rapidly. nDrugs given to farmed fish to prevent disease pass through them into the environment. nMany pens release concentrated waste in the form of nitrates, leading to plankton blooms. nAquatic farms consume resources that wild organisms would use. nRaising species not indigenous to the area raises a risk of throwing the local ecological balance off should some escape. nIt can also compromise the gene pool of wild species if the domestic animals breed with them. New Medicines from the Oceans nBioprospecting is the search for organisms with pharmacological or other chemical benefits. nBioprospecting is important in the development of new drugs because it is in nature that chemists often find new ways to fight disease. Biological Resources – Algae, Aquaculture and Medicine Chapter 15 Pages & 15-29

16 MenuPreviousNext Fisheries for Food and Industry nAbout 18% of the protein we eat in the US comes from the ocean. Worldwide, it accounts for only about 4% and varies by nation and culture. nCommercially important fish are found primarily in two places: the water of the continental shelves and a few offshore regions with abundant upwelling. nContinental shelves and upwellings have high productivity because of the ample supply of nutrients and sunlight. nClupeids – herring, sardines and anchovies account for the largest single group that is taken for commercial harvest. nIndustrial fishing is catching for purposes other than direct human consumption. Over one third of the commercial fish catch is industrial. Biological Resources – Fish Chapter 15 Pages & 15-31

17 MenuPreviousNext Trends in the Worldwide Commercial Fish Catch nSince WW II, the worldwide annual catch has been greatly increasing. nThe commercial extinction of many target fish, e.g. orange roughy, and the decline of others including cod fisheries, raises doubts in the minds of scientists about the accuracy of the FAO’s estimates and reports. nPredicted trend is that soon the worldwide fisheries will not be able to meet the rising demand. Even the FAO estimates that by 2010, the worldwide catch will fall short of the demand. Biological Resources – Fish Chapter 15 Pages to 15-33

18 MenuPreviousNext Maximum Sustainable Yield and Overfishing nThe concept of maximum sustainable yield lies at the heart of fisheries management.  It is the number of a target species that fisheries can take without jeopardizing future populations. nThe precise definition of overfishing is taking more of a species than the maximum sustainable yield. nEvidence indicates overfishing in virtually all the world’s fisheries.  Fleets catch less than in past years, yet have to range farther for fish.  Indications are that half the marine fisheries are overfished or already commercially extinct.  The FAO estimates that 70% of the worldwide fish stocks are overfished or depleted.  The National Marine Fisheries Service estimates that 50% of the fish stock in US waters is over fished. The State of the World’s Fisheries – A Bleak Picture Chapter 15 Pages & 15-36

19 MenuPreviousNext The Problems with Overfishing nThe fishing industry has become more efficient and blind to the threat.  By refining technology and methods, they are taking ever larger proportions of declining fish stocks.  They are also responding by turning to new, unexploited fisheries. nProblems associated specifically with overfishing species low in the food web. nThe first is that these species are food for higher species. nA second problem is that it allows the proliferation of other organisms low on the food web. nThere are also indirect problems related to overfishing:  1. Humans aren’t the only organisms eating fish. Alaskan stellar sea lions are in decline. The decline is thought to be the result of heavy commercial fishing for pollock.  2. By-catch is the unintentional capture of organisms. nEstimates indicate this accounts for 25% of the catch. By-catch involves not only fish, but birds, mammals, fish, and reptiles. The State of the World’s Fisheries – A Bleak Picture Chapter 15 Pages & 15-37

20 MenuPreviousNext Recommendations for Sustaining the World’s Fisheries nIn June 2003, the Pew Ocean Commission, a respected group of US scientists, wildlife advocates, natural resource managers, and politicians made these four recommendations to restore US fisheries as sustainable biological resources.  1. Make the principal objective of US fisheries policies the protection of marine ecosystems.  2. Create an independent government agency responsible for managing ocean resources.  3. Invest in more marine research over the next five years. The commission recommended doubling current funding.  4. Establish a network of marine reserves or protected areas. The State of the World’s Fisheries – A Bleak Picture Chapter 15 Pages & 15-38

21 MenuPreviousNext Commercial Fishing Methods The Economics of Commercial Fishing nIt costs more to catch fish than is made from selling fish. Fishing fleets spend about $124 billion to catch $70 billion in fish. The fishing industry survives because of global government subsidies. Commercial Fishing Chapter 15 Pages to Five Primary Methods of Commercial Fishing

22 MenuPreviousNext The Origin of Territorial Waters nIn 1604, Dutch jurist Hugo Grotius wrote De Jure Praedae (On the Law of Prize and Booty), the most important part of which was a chapter defending free access to the sea by all nations. It took about 100 years, but finally it was internationally recognized. nNations agreed to territorial water over which coastal nations had complete control. The seaward boundary was set at 5 kilometers (3 miles), not coincidentally the maximum effective range for cannon fire at the time. Beyond this limit was the high sea (international waters) belonging to no one. The Truman Proclamation nIn 1945, President Harry Truman issued this proclamation claiming all physical and biological resources on the continental shelf of the continental United States.  Very quickly other nations followed suit.  The proclamation changed the concept of international waters by widening the concept of territorial water. Who Owns the Sea? Chapter 15 Pages & 15-44

23 MenuPreviousNext Exclusive Economic Zones nUNCLOS is the United Nations Convention of the Law of the Sea.  It established the concept of the exclusive economic zone (EEZ). A nation’s EEZ extends 370 kilometers (200 nautical miles) from the shoreline. nWithin EEZ, a nation has complete control of all resources, economic activity, and environmental protections.  Areas beyond the EEZs are the high seas or international waters belonging to no one country.  One of the more controversial aspects of UNCLOS was the establishment of the International Seabed Authority plan. This plan said that mineral wealth recovered from the seabed in international waters must be shared internationally. nBecause mineral wealth is to be shared internationally, the US, Canada, and Great Britain have not ratified the UNCLOS treaty.  In 1983, the US proclaimed its own EEZ within 200 nautical miles of its coasts. This proclamation shares the limits, but omits provisions about shared resources in international waters. Several other countries that have not ratified UNCLOS have similarly declared EEZs of their own. Who Owns the Sea? Chapter 15 Pages to 15-46

24 MenuPreviousNext The Ultimate Resource nBiodiversity is the concept that the preservation of the Earth and ecosystems relies on the broad genetic diversity of all the organisms on Earth. nWe never know when losing one or more species is losing too many or just how important each single species is or when losing this species is the one that counts. nThe importance of biodiversity is that every organism is a biological resource. Even if there is no direct use of an organism, it is important because it is part of what keeps life going. Biodiversity and the Future Chapter 15 Pages & 15-47


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