Human Effect on Ocean Ecosystems Flashcards
where does most habitat disruption occur in the ocean and why?
close to shore, due to unplanned or poorly planned human development
approximately ______ of all corals reefs have been lost or are at risk: _______ of reef building coral species face extinction
one fourth, one third
zooxanthellae can only withstand a temperature change of __________
1.4 degrees farenheight
what is trawling and why is it a threat?
nets are dragged along the bottom of the ocean, causing re-suspension of sediments, which can kill many suspensions as well as deposit feeders
what is pollution
the human introduction of a substance that reduces the quality of the environment
most marine pollutants are the result of ____________
land based activities
describe the process of eutrophication
phytoplankton cells die and drop to the bottom , causing massive amounts of organic matter increasing bacteria decomposition
these organisms consume great amounts of oxygen, developing anoxic conditions
blooms also decrease light availability for photosynthesizers
Sewage pollution source
homes, city buildings, stormwater runoff.
industrial sewage from factories
what kinds of substances can sewage contain?
disease causing organisms
heavy metals
where are organisms typically most threatened to be coated in oil?
organsims living in estuaries, seagrass meadows, mangrove forests, corals
how are organisms affected by oil pollution?
it can affect reproduction, growth, development, and behavior
organisms may also die from their feathers or fur becoming coated in oil
sources of oil pollution
Natural seeps (most)
Land-based pollution
Transportation of oil
Exploration and exploration and extraction (least)
what are some examples of toxic substances in pollution?
Chlorinated hydrocarbons, polychlorinated biphenyls (PCB’s) and heavy metals
where do chlorinated hydrocarbons end up in an organism?
dissolved in the fats/lipids of organisms and are passed along the food chain.
what is biological magnification
when a toxic substance accumulated in an organisms tissues from eating other organisms because they are not biodegradable
