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Chapter 17: Marine Resources. Laws and regulation. Mare Liberum Territorial sea 1958 to 1982 UN Law of the Sea Ratified in 1993 International law. Law of the sea. Coastal jurisdiction 12 n. miles EEZ Exclusive Economic Zone 200 n. miles Free passage International Seabed Authority
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Laws and regulation • Mare Liberum • Territorial sea • 1958 to 1982 UN Law of the Sea • Ratified in 1993 • International law
Law of the sea • Coastal jurisdiction 12 n. miles • EEZ Exclusive Economic Zone 200 n. miles • Free passage • International Seabed Authority • Law of the Sea Tribunal
EEZ of United States Fig. 17-1
Fisheries • Fish caught commercially • Five ecosystems • Non-tropical shelves • Tropical shelves • Upwelling • Coastal and coral systems • Open ocean
Fish recruitment • Fertilization of eggs • Survival of fish larvae • Survival of juvenile fish • Mortality losses huge until fish matures
Primary productivity and fisheries Relationship to nitrogen influx Fig. 17-2
More nitrogen at upwelling • Duration of upwelling • Rates of upwelling • Moderate • Too slow • Too fast
World catch • Fish production • Potential world fishery about 100 to 120 million metric tons • Overfished areas • Intended catch and bycatch
Bycatch • Caught incidentally • Tuna and dolphins • Marine Mammals Protection Act • Driftnets or gill nets • Banned in 1989
Fisheries management • Difficulties • Regulation of fishing vessels • Catch limits • Many countries • Migrating fish • Human activities in one area impact another • Economic concerns of fishers
Mariculture • 37% of total world fishery • Fish • Crustaceans • Shrimp and prawn most successful • Bivalves • Also successful • Algae • Mainly seaweed
Energy from oceans • Advantages • Nonpolluting • Huge • Renewable • Readily available along coasts
Power from • Offshore winds • Currents • Waves • Tides • Thermal energy (OTEC)
Mineral resources • Petroleum • Offshore about 30% of total world production • Likely to increase in future • Deeper ocean to be exploited
Gas hydrates • Sand and gravel • Phosphorite • Metal sulfides • Manganese nodules and crusts • Cobalt (strategic)
Chemical resources • Freshwater from desalination • Distillation • Solar humidification • Electrolysis • Reverse osmosis • Freeze separation
Reverse osmosis Fig. 17-24
Evaporative salts • Halite, common table salt • Gypsum building material • Chemical industrial uses
Pharmaceutical drugs from the sea • Soft-bodied marine organisms chemical “warfare” • Antibiotic • Anti-inflammatory • Anti-viral • Anti-tumor • Anti-cancer