ch.7 environmental
environmental functions of wetlands
-trapping and filtering sediments, nutrients, and pollutants, which keep these materials from entering lakes, reservoirs, and oceans; -reducing the likelihood of a flood, protecting agriculture, roads, buildings, and human health and safety; -buffering shorelines against erosion; -providing spawning grounds and habitat for commercially important fish and shellfish; -providing habitat for endangered species and migratory wildlife; -providing recreational activities for humans
land and climate
A river changes with the ________ & ________ through which it flows.
eutrophic
A(n) ______ lake has a large amount of plant growth due to nutrients.
the ocean
An arctic ecosystem depends almost entirely on ______ for its available food.
27
An estimated ______ % of all coral reefs are threatened by human activities.
benthos
Barnacles are a type of ________, or bottom dwelling, organisms.
absorbs
Because water ________ sunlight, photosynthesis is limited to the upper 100 meters of the ocean.
calcium carbonate and limestone
Coral polyps secrete skeletons of __________ that slowly accumulate & form coral reefs.
warm
Corals live only in shallow, _______ water where there is enough light for photosynthesis.
slowly
Downstream, a river often widens & flows more ______.
runoff
Excessive nutrient growth in an aquatic ecosystem can be accelerated by ________.
nekton
Fish are a type of ________, or free-swimming, organisms.
nutrient
In estuaries, fresh water & saltwater mix, forming a(n) ______ trap.
barrier
Long, thin _________ islands typically run parallel to a shore.
snow melt
Many rivers originate from _______ in mountains.
nonwoody and woody
Marshes are dominated by ________ plants while swamps contain mainly _______ plants.
rhiziods
Mosses use ________ to anchor themselves to rocks near churning river headwaters.
land
Most ocean pollution can be traced to activities on __________.
phytoplankton
Most of the food in aquatic ecosystems is produced by _____
What mainly distinguishes nekton from benthos?
One swims freely and the other often lives attached to a hard surface.
base
Plankton form the _____of the marine food web.
salinity
The amount of dissolved salts in water is known as _________.
open ocean
The least productive marine ecosystem is the ______.
brakish
The water in salt marshes is saltier than the water in _______ marshes.
nekton
Three groups of aquatic organisms include plankton, ________, and benthos.
phytoplankton and zooplankton
Two types of plankton are microscopic plants called ________ and microscopic animals called
swiftly
Upstream, a river is usually cold & flows _______ through a shallow riverbed.
marshes
contain nonwoody plants such cattails
benthic zone
dead and decaying organisms reach-- the bottom of a pond or lake, which is inhabited by decomposers, insect larvae and clams
mangrove swamps
dense growths of mangrove trees in swampy areas--found in tropical and subtropical zones---help to protect the coastline from erosion and reduce the damage from storms
zooplankton
drifting animals which may be microscopic or as large as a jellyfish
limnetic zone
farther from the shore, in the open water-- there are no rooted plants
swamps are commonly found on
flat, poorly drained land
Phytoplankton
food base for most aquatic ecosystems
nekton
free swimming organism such as fish and whales
alkaline fens
ideal habitat for many amphibians, such as frogs, because of the continuously moist environment
coral bleaching
if the water is too hot or cold for too long, or it is too muddy, polluted, or high in nutrients, the algae that live in the corals will leave or die-- as a result the coral tune white
salt marshes, form
in estuaries, where rivers deposit their load of mineral-rich mud
acidic bogs
in freshwater swamps--- filled with sphagnum or peat moss, which are found in warmer areas and cypress swamps
through photosynthesis
in the limnetic zone, phytoplankton make their own food
wetland
includes area where land is periodically under water
runoffs
is precipitation that can carry pollutants like fertilizers from land into bodies of water
eutrophic lake
lakes with large amounts of algae and plant growth from excessive nutrients
freshwater ecosystems
lakes, ponds, wetlands, rivers, and streams
coral reefs
limestone ridges built by tiny coral animals called coral polyps and the algae that live inside them
In which aquatic zone would you be likely to find cattails and reeds?
littoral
rhiziods
near the headwaters, mosses anchor themselves to rock by using rootliked---
littoral zone
near the shore, aquatic life is diverse and abundant
barrier islands
often run parallel to sandy shores-- they help to protect the mainland and the coastal wetlands from storms and oceans waves and often provide habitat for wildlife
plankton
organisms that cannot swim against currents, they are also drifters
Chemosythetic
organisms that derive nutrients from chemicals in the water or substrate
the type of plankton that produces most of the food in an aquatic ecosystem is called
phytoplankton
base of marine food web
plankton
runoff
potential threat to an estuary
the majority of organism are found in
shallow, coastal water
why doesn't photosynthesis occir in deep ocean water
there is no sunlight
organism that live in estuaries must adapt to changes in
water level and salinity
temperature
a factor that determines where aquatic organism live
estuary
an area in which fresh water from a river mixes with salt water from the ocean
eutrophication
an increase in the amount of nutrients
coastal wetlands
are covered by salt water for all or part of the time--- also filter out pollutants and sediments, protect shorelines from erosion, and provide recreational areas for boating, fishing, and hunting
swamps
are dominated by woody plants, such as flood-tolerant trees and shrubs
freshwater wetlands
areas of land with special soils and plants, that are covered with fresh water for at least part of the year
benthos
bottom dwelling, such as mussels, worms, and barnacles
rivers
can originate from underground springs, snow melts in mountains, or where smaller streams merge together