marine pollution

marine pollution

introduced by humans of substances, heat, or sound that decreases the quality of the marine environment

point source

any single identifiable source of pollution from which pollutants are discharged

examples of point source

pipes, ditches, ships, factory smokestack

non-point source

any source of water pollution that doesnt meet the legal definition of “point source”

• often run off

bioaccumulation

pollutants enter individuals organisms and are stored or “build up” in tissues

biomagnification

pollutants become increasingly concentrated as you move up trophic levels

eutrophication

artificial enrichment of waters (by humans) that causes an algal bloom that then dies, decomposes, all the O2 is used

dead zones

hypoxic (oxygen-poor) water

• suffocates benthic organisms

how many dead zones are world wide

more than 500

sewage sludge

semisolid material after sewage treatment

• human waste, oil, heavy metals

primary treatment sewage sludge

solids settle and dewater

secondary treatment sewage sludge

treat sludge with bacteria-killing chlorine

clean water act 1972

no dumping of sludge in ocean after 1981

___ and _____ dumped inshore until 1986 and offshore until 1993

NY and Philly

Boston sewage sludge

sludge entered the boston harbor until 90’s, now pipe further off shore

oil spill are caused from…

• accidental

• extraction

• loading/unloading accidents

• intentional spill during war

fate of oil in the ocean

• sticking to surface

• oxidize into the atmosphere

• oil in water column

• pollutant gasses released into atmosphere

the five heavy metals are

zinc

copper

lead

silver

mercury

where are heavy metals from?

sewage

mining

chemical / power plants

minamata disease

chemical plant in Japan released mercury in 1938

• methyl mercury toxic to living organisms

• caused ecological changes & poisoned humans

synthetic materials

persistent biologically active chemicals widespread in ocean

examples of synthetic materials

• pesticides

• industrial chemicals

• pharmaceuticals

DDT

insecticide was widely used in 50’s

affects of DDT on marine life

caused a decline in bird populations

thin eggshells

• long island osprey

• california brown pelican

solid waste

• non point source

most common: cigarettes followed by plastic bags & bottles + cans

ocean dumping

dumping of trash / plastic into the waters

US lakes, rivers, bays, sounds, and three miles from shore

illegal to dump everything

3-12 miles

illegal to dump everything (plastic/dunnage) and garbage unless it is ground to less than one inch

12-25 miles

illegal to dump plastic and dunnage only

outside 25

illegal to dump plastic only

fate of plastics

plastics do not degrade, they just break down into smaller pits (microplastics)

how many great garbage patches are in the oceans?

at least five, one in each major ocean basin

how do ocean garbage patches form?

marine debris are driven by ocean currents accumulating in the center of ocean gyres

impacts of garbage patches on marine life

• cause death by becoming trapped, they starve or suffocate

• eating plastics kill the animals

• plastics can get rapped around animals body parts and hinder there ability to live

thermal pollution

heated water is added into the marine environment that alters O2 levels, reproductive cycles, and biodiversity

sound pollution

loud noises that alter marine life lifestyle

humans increased sound levels ___x in last 50 years

10

sound perception organs

cilia

bladders

ossicles

otoliths

why is it important to reduce pollution?

• saves money

• increases biodiversity

trash skimmers

removes floating debris from the waters by attracting them, trapping them, storing them and releasing water

the ocean clean up

project founded by a college student to clear debris from the five major garbage patches

in hawaii _____ ____ are being converted into energy

fishing nets