Chapter 4: Ecosystems & Communities

Front 1

weather

Back 1

the day-to-day condition of Earth's atmosphere at a particular time and place

Front 2

climate

Back 2

the average, year-after-year conditions of temperature and precipitation in a particular region

Front 3

greenhouse effect

Back 3

the natural situation in which heat is retained by a layer of greenhouse gases

Front 4

polar zones

Back 4

cold areas where the sun's rays strike Earth at a very low angle between 66.5 N and 90 S latitudes

Front 5

temperate zones

Back 5

between the polar zones and the tropics

Front 6

tropical zone

Back 6

near the equator, between 23.5 N and 23.5 S latitudes

Front 7

biotic factors

Back 7

the biological influnences on organisms within an ecosystem

Front 8

abiiiotic factors

Back 8

physical, or nonliving, factors that shape ecosystems such as temperature, precipitation, and humidity

Front 9

habitat

Back 9

the area where an organism lives

Front 10

niche

Back 10

the full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions

Front 11

resource

Back 11

any necessity of life, such as water, nutrients, light, food, or space

Front 12

competitive exclusion principle

Back 12

no two species can occupy the same niche in the same habitat at the same time

Front 13

predation

Back 13

an interation in which one organism captures and feeds on another organism

Front 14

symbiosis

Back 14

any relationship in which two species live closesly together

Front 15

mutualism

Back 15

relationship between two species in which both benefit

Front 16

commensalism

Back 16

one member of the association benefits and the other is neither helped nor harmed

Front 17

parasitism

Back 17

one organism lives on or inside another organism and harms it

Front 18

ecological succession

Back 18

the series of predictable changes that occurs in a community over time

Front 19

primary succession

Back 19

succession that occurs on land where no soil exists

Front 20

pioneer species

Back 20

the first species to populate an area

Front 21

secondary succession

Back 21

process by which community interactions tend to restore the ecosystem to its original condition after a disturbance

Front 22

biome

Back 22

a complex of terrestrial communities that covers a large area and is characterized by certain soil and climate conditions and particular assemblages of plants and animals

Front 23

tolerance

Back 23

ability to survive and reproduce under conditions that differ from their optimal conditions

Front 24

microclimate

Back 24

the climate in a small area that differs from the climate around it

Front 25

plankton

Back 25

general term for the tiny, free-floating organisms that live in both freshwater and saltwater environments

Front 26

phytoplankton

Back 26

unicellular algae

Front 27

zooplankton

Back 27

planktonic animals

Front 28

wetland

Back 28

an ecosystem in which water either covers the soil or is present at or near the surface of the soil for at least part of the year

Front 29

estuaries

Back 29

wetlands formed where rivers meet the sea

Front 30

detritus

Back 30

tiny pieces of organic material that provide food for organisms at the base of the estuary's food web

Front 31

salt marshes

Back 31

temperate-zone estuaries dominated by salt tolerant grasses above the low-tide line, and by seagrasses under water

Front 32

mangrove swamps

Back 32

costal wetlands that are widespread across tropical regions with mangroves as the dominant plant

Front 33

photic zone

Back 33

well-lit upper layer of the ocean where photosynthesis occurs

Front 34

aphotic zone

Back 34

premanently dark layer of the ocean below the photic zone. only chemosynthetic autotrophs can surive here

Front 35

zonation

Back 35

the prominent horizontal banding of organisms that live in a particular habitat

Front 36

costal ocean

Back 36

extends from the low-tide mark to the outer edge of the continental shelf

Front 37

kelp forests

Back 37

costal ocean community whose dominant organism is kelp

Front 38

coral reefs

Back 38

tropical costal environments named for the coral animals whose hard, calcium carbonate skeletons make up their primary structure

Front 39

benthos

Back 39

organisms attached to or near the bottom of the ocean such as sea stars, anemones, and marine worms