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Ch. 4- Ecosystems and Communities

STUDY
PLAY
weather
Day to day condition of earth's atmosphere at a particular time and place
climate
the average overall weather conditions over a long period of time
greenhouse effect
the trapping of the sun's heat by gasses of the atmosphere such as carbon dioxide and methane
polar zone
extreme cold zones above 66.5 degrees north and below 66.5 degrees south latitudes
temperate zone
moderate temperature zones between 23.5 and 66.5 degrees latitude, north and south of the equator
tropical zone
warmest and most humid of the 3 major zones, between the equator and 23.5 degrees North and 23.5 degrees south latitude
biotic factor
the biological influences on an organism within an ecosystem
abiotic factor
the non-living environmental factors (temperature, humidity, wind, etc) that affect an ecosystem
habitat
the biotic and abiotic factors that make up that particular area in which an organism lives
niche
the specific way in which an organism uses its habitat to survive
resource
any naturally occurring biotic or abiotic factor that enhances an organism's ability to survive
competitive exclusion
fundamental rule in ecology that states that no two species may occupy the same niche in the same environment at the same time (blue bird and starling)
predation
relationship in nature in which one organism (predator) captures and feeds on another (prey)
symbiosis
relationship in nature in which two organisms live closely to each other for survival
mutualism
symbiotic relationship in which both organisms benefit from each other (lichen)
commensalism
relationship in which one member benefits while the other is neither helped nor hindered (ex: barnacles on whales get food, but don't hurt or help the whale)
parasitism
one organism benefits, while hurting the other organism's chances of survival (tapeworm)
ecological succession
orderly, predictable change in community over time in response to natural or human disturbance in an area
primary succession
initial species to start growing in an area devoid of soil or life
pioneer species
first organisms to populate an area usually lichen and 'exerserees' - 'rock eaters'
secondary succession
first organisms to occupy land stripped of life but not soil (cherry tree after fire)
climax community
area in which succession ends in mature, relatively stable old-growth forests
biome
particular physical environment occupied by characteristic plants and animals (desert biome vs. tropical vs. temperate forest biomes)
microclimate
small area within a larger area with its own distinct climate
canopy
dense top layer of leaves in a mature forest
understory
the shorter vegetation that lives in the shadows below the forest canopy
deciduous
trees that drop their leaves at the end of the growing season in preparation for winter
coniferous
gymnosperm tree, that reproduces with seed bearing cones. Most keep their need-shaped leaves through the winter
humus
decaying organic matter found on the forest floor
taiga
coniferous forests found at the northern edge of temperate zone biomes
permafrost
permanently frozen sub-soil found in tundra biomes of extreme northern regions
plankton
any plant or animal-like organism in the ocean that floats and is at the mercy of the tides
phytoplankton
any plant-like organism that floats in the ocean and is at the mercy of the tides
diatom
single-celled photosynthetic organisms made of silicon shells (diatomaceous earth for pool filters)
zooplankton
often single-celled animal ilk organisms that float and are at the mercy of the tides
nekton
any animal that can swim purposefully against the tides (whales, squid, people, fish)
wetland
ecosystem made of wet, marshy or near marshy land either freshwater or salt water
estuary
wetlands where rivers meet the sea, providing shelter lush breeding grounds for many life forms
detritus
organic particles that provide the base for many food webs
salt marsh
temperate zone estuaries made up of salt tolerant grasses above low tide line and underwater seagrass
mangrove swamp
coastal wetlands important in controlling shore erosion, made up of salt water tolerant trees called 'mangroves' as well as seagrasses
photic zone
well lit area 300 to 600 feet below ocean surface where sun penetrates, allow photosynthesis
aphotic zone
area in ocean below the photic zone where photosynthesis does NOT occure
zonation
horizontal banding of organisms in the ocean brought on by competition and environment
coastal ocean
relatively shallow area of the ocean that starts at the ocean's edge and extends to the outer edge of the continental shelf
kelp forest
coastal edge community made up of underwater brown seaweed called kelp
coral reef
structures constructed of tiny sea creature exoskeletons that accumulate in warm offshore oceans to make reefs
benthos
sea creatures that live on or near the ocean bottom (clams, lobsters, oysters, starfish, etc)