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51 terms


all earth's ecosystems
abiotic factors
nonliving or physical factors that shape an ecosystem
trophic structure
the nutritional relationships among the producers and consumers in an ecosystem
organisms that consume plants or algae, primary consumers
meat eaters, eat herbivores, secondary consumers
energy pyramid
the diagram of a trophic structure
10% rule
each level recieves about one tenth of the energy of the level below it
the total quantity of living matter at each trophic level
the rate at which biomass forms
a predator species consumes a prey species
the particular combination of resources that a species is adapted to exploit
competitive exclusion principle
two species cannot occupy the same niche in the same ecosystem for long
three types of interactions between species: mutualism, parasitism, commensalism
both species benefit
a parasite lives in or on a host that provides it with nutrients or other resources
one organsism benefits and the other is unaffected
limiting factors
the idea that the supply of light, water, or other needs can limit the rate of a process like photosynthesis
exponential growth
growth pattern in which the individuals in a population reproduce at a constant rate
population density
the number of individuals per unit of land area or water volume
logistic growth
a population that develps in a new environment may begin to grow exponentially, but it soon slows to a linear growth pattern and eventually approaches a stable maximum
carrying capacity
the largest population of a species that the environment can support
boom-and-bust cycle
exponential growth leads to a period when the population exceeds its carrying capacity, causing the population to decrease rapidly or crash
predator-prey cycle
the cycles of the predators lag behind the cycle of the prey population
Large geographic areas with similar climates and ecosystems
tropical rain forest
biome near the equator with warm temperatures, wet weather, and lush plant growth
a flat grassland in tropical or subtropical regions
a barren region with little or no rainfall, usually sandy and without trees
perennial vegetation
plants that live more than one year
plants having thick leaves with large cells able to store water
type of vegetation made up of dense forests of shrubs and short trees, common in mediterranean climates
temperate grasslands
receive less water and are subject to lower temperatures than savannas. North american prairie
temperate deciduous forests
temperate areas, moderate Precipitation, Hot summers, cold winters, soil is rich in organic material
high elevations, harsh winters, short summers, lots of snow, not much water until the spring thaw
very high altitudes, plants are matlike, continuously frozen ground
producers near the surface of the water where sunlight penetrates
small animals that feed on phytoplankton
photic zone
the shallow top layer of the ocean where enough light penetrates for photosynthesis to occue
aphotic zone
below photic zone, light is insufficient there for photosynthesis
interidal zone
shore area between the high-tide and low-tide marks
neritic zone
the shallow water over the continental shelf
oceanic zone
where the sea floor drops sharply, large ocean animals live here
pelagic zone
the open water not associated with the seafloor
benthic zone
the seafloor
abyssal zone
the area of the benthic zone where light does not penetrate
dispersing organisms successfully settle in a new area
the new organism
primary succession
succession that occurs on surfaces where no soil exists
secondary succession
succession on a site where an existing community has been disrupted
plants that only live for one year
climax community
when the web of interaction is so intricate that no more species can fit in it, it has reached a stable equilibrium
common pool resources (commons)
goods and services provided by an ecosystem that is shared by many but controlled by no one person