CH13 the oceans resources

law of the sea treaty

states that the water, seabed, and sub-seabed resources of the continental shelf belong to the nearest country within 200 nautical miles offshore or the edge of the continental shelf

exclusive economic zone/eez

200 nautical miles offshore or to the edge of the continental shelf, coastal state has the power to regulate fishing, mineral resources, pollution, and research

makes up 40% of the worlds ocean

who controls the oceans resources past the eez?

united nations charter, the International Seabed Authority

how can fish production be calculated?

we need to number of trophic levels and the ecological efficiency of transfer between levels

precautionary principle

advocates restraint on damaging fishing practices even when solid scientific proof of a decline in fish stocks is lacking

marine reserves

areas of the ocean set aside where no fishing is allowed, 2% of the world ocean is one as of 2019

benefits of marine reserves

it increases…

• diversity

• density

• biomass

• body size

• reproductive potential

of fish

mariculture

marine agriculture, 1 in 4 fish eaten today are raised in farms, about 40% of salmon and shellfish are raised on farms

which organisms are currently maricultured?

• oysters

• mussels

• shrimp

• salmon

• plaice

what makes a species suitable for mariculture?

• marketable for food

• inexpensive to grow

• trophically efficient

• reach harvestable size quickly

• resistant to disease + parasites

• cultivation methods match local resources and conditions

• supply local markets

• promote local business opportunities

problems with mariculture

• carnivorous animals must be fed fishmeal

• pollutes coastal waters

• destroys habitats

what are oceans petroleum resources?

resources formed from ancient deposits of marine algae that rise and settle under impermeable rock barriers, usually on the continental shelf + slope

gas hydrates

methane molecule inside a frozen water “cage” in the deep sea around 300-2000m down that give us a tremendous supply of natural gas

sand + gravel (your favorite!)

deposits from the ice age found on continental shelf that are used for construction and beach replenishment, but the mining of it disrupts fragile benthic ecosystems

manganese nodules

mainly Mn -oxide along with irons, nickels, cobalts, coppers, zinc, and lead foud beyond the eez at depths of >2000m

cobalt rich ocean crust

crusts found on the sides of seamounts and islands in depths of 1-2.5km used in the production of jet engines

phosphate deposits

accumulates on shallow marine seafloor below highly productive waters that grow 1-10mm every thousand years, used as agriculture fertilizer

when did the worlds commercial fish catch reach its maximum?

around 1990

where are most of the worlds commercial fish caught?

coastal upwelling regions

historically, the most productive new england fishery is found where?

georges bank

what is not a consequence of overfishing?

increase in numbers of sexually mature individuals

which characteristic would make a marine organism unsuitable for mariculture?

low ecological efficiency

petroleum reserves beneath the seafloor tend to be concentrated in what type of rock?

permeable sandstone or shale

what is a gas hydrate?

methane molecule encased in ice

ferromanganese nodules are mined in the vicinity of what part of the seafloor?

deep sea floor

what three fishing techniques are damaging to fish stocks?

bottom trawling, cyanide fishing, dynamite fishing