1
How much of the earth’s surface does saltwater and freshwater aquatic zones cover?
about 71%
what are the 3 layers of aquatic life zones?
surface, middle, and bottom
what is the euphotic zone?
The upper layer where sun can penetrate
do open oceans how high or low amounts of nutrients?
low
what determines the major types of organisms found in a aquatic environment?
salinity
what are the oceans 2 major life zones?
coastal zone and oepn sea
which lake has more nutrients Oligotrophic or eutrophic?
eutrophic
where are dissolved oxygen levels higher?
near the surface due to photosynthesis
true or false: The damage humans cause to these water zones are not always visible
true
how much of coastal zones have already been lost?
1/3
how are lakes classified?
by reference to their plant nutrients
Are coral reefs better in warm or cool waters?
warm
How much of the U.S. wetlands have been lost since the 1600s?
more then 50 %
what are the 3 vertical zones of the open sea?
euphotic, bathyal, and abyssal
what are lakes in between the 2 extremes called?
mesotrophic lakes
what percent of worlds population lives on the coast?
40
what 3 things feed into lakes?
Rainfall, melting snow, stream drainage
what are the 3 aquatic life zones identified along stream flow?
source, transition, and floodplain
what is the ideal water temperature for coral reefs?
18-30 degrees celsius
what are the 4 zones a lake can have?
littoral, limnetic, profundal, and benthic