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 Law of the Sea Tribunal

EEZ of world

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)

Divergent and convergent plates and metallic sulfides

Chemical resources Freshwater from desalination Distillation Solar humidification Electrolysis Reverse osmosis Freeze separation

Reverse osmosis Fig

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

End of Chapter 17: Marine Resources