COMMUNITY ECOLOGY Flashcards
variety of life on earth
biodiversity
collection of physical resources found in a functioning ecosystem combined with the contribution each species make
ecosystem services
differences in the species composition of biomes
community diversity
signifies distinct characteristics, habits, and gene pool which can be due to evolution
species diversity
no individual is similar to the other, that the segregated gene pairs cause variations among individuals
genetic diversity
a taxon is neither critically endangered or endangered but is facing a high risk of extinction in the wild in the future
vulnerable
the taxon does not satisfy criteria for critically endangered, endangered, and vulnerable
lower risk
there is insufficient information to make direct or indirect assessment of its risk of extinction based on its distribution or population status
data deficient
array of species in a community depends on physical factors (climate) biological factors (which species arrived first) and the frequency of disturbances
community change
species composition of a community can change over time
successional change
species alter the habitat in ways that allow other species to come in and replace them
ecological succession
species that are opportunistic colonizers of new or newly vacated habitats; have high dispersal rates, grow and mature fast, produce many offspring; help and improve the soil
pioneer species
a process that begins when pioneer species colonize a barren habitat with no soil
primary succession
a disturbed area within a community recovers; if improved soil is still present, can occur fast; common in abandoned fields and burned forests
secondary succession
factors that influence succession
physical factors
chance events
Extent of disturbances in the habitat
species that has a disproportionately large effect on community structure
Keystone species
species that is especially sensitive to disturbance and can be monitored to assess the health of a habitat
Indicator species
course of recovery in living communities and restoration of functions after a disturbance
Succession
anticipated a single climax community (mature community) regulated climate which is the termination to the process of succession
Frederick Clements (1916)
Mature community
Climax community
big islands tend to support more species than small ones; more colonists will happen upon a larger island simple by virtue of its size
area effect
a well-known productive ecosystem; found in tropical and temperate areas
forest
the forests found along the earth’s equatorial region
tropical moist forest
types of tropical moist forest
tropical lowland rainforest
upland mossy or cloud forest
main plants are the conifers (evergreen trees with seed-bearing cones)
coniferous forest
forms between the polar ice cap and the belts of boreal forests in the northern hemisphere
arctic tundra
frozen layer
permafrost
occur when there is an average rainfall of less than 25cm;intermittent rainfall supports some species of plants and animals
desert
ecosystems can withstand selective pressures caused by grazing of herbivores; annual rainfall is enough to prevent desert drom forming but not enough to support woodlands
grasslands
warm n summer but cold in winter; annual rainfall of 25 to 100 cm; with rains throughout the year; grasslands in temperate areas
temperate prairies
broadbelt of grasslands with a few scattered shrubs and trees; warm year round; abundant wildlife; grasslands in tropical region
tropical savannas
gradients in light penetration, temperature and dissolved gases affect the distribution of life in aquatic habitats
freshwater
a body of standing fresh water; if sufficiently deep, will have zones that differ in physical characteristics and species composition
lakes
newly formed lake; deep, clear, and nutrient poor with low primary productivity
oligotrophic
natural or artificial processes that enrich a body of water with nutrients, allowing producers to grow and productivity rises
eutrophication
nearest shore, sunlight penetrates all the way to the lake bottom and aquatic plants are primary producers
littoral zones
upper well-lit, open waters, phytoplanktons are the primary producers
limnetic zone
light does mot penetrate, consumers depend on food produced above; debris that drifts down feeds detritivores and decomposers
profundal zone
flowing water ecosystems start as freshwater springs or seeps; as they flow downslope, they grow and emerge
streams and rivers
factors affecting flow volume and temperature
rainfall
snowmelt
geography
altitude
shade cast by plants
near the coast of continents and islands, concentrations of nutrients support some of the world’s most productive aquatic ecosystems
coastal ecosystems
an enclosed coastal region where seawater mixes with nutrient rich freshwater from rivers and streams
estuary
salt tolerant woody plants that live in sheltered areas along tropical coasts
mangroves
organisms that live along ocean shores are adapted to withstand the force of the waves and repeated tidal changes; along rocky shores, where waves prevent detritus from piling up, algae are the producers in grazing food chains
rocky and sandy shores
highly diverse and highly threatened marine ecosystems; wave resistant formations that consist primarily of calcium carbonate secreted by generations of coral polyps
coral reefs
when stressed, coral polyps expel dinoflagellates; ejecting them turns the coral white
coral bleaching
from its upper, brightly lit waters to the hydrothermal vents on its deep, dark floor, the ocean is filled with life
open ocean
the water over continental shelves and the more extensive waters farther offshore
pelagic
ocean bottom, its rocks and sediments
benthic
