Ecology & the Biosphere
Chapter 52
Ecology
Study of how organisms relate to one another & their environment
Fig. 52-5
Kangaroos/km2
0–0.10.1–11–55–1010–20> 20Limits ofdistribution
Fig. 52-9
Ecology
Organism (behavioral ecology)Population (several individuals of
same species)Community (different species that
live in a particular area)Ecosystem (abiotic factors & all the
species that live in that area)Biosphere (all the living communities
on earth-global ecosystem)
Environment
Abiotic factors (nonliving):Temperature WaterSunlightSoil /rocksClimate
Environment
ClimateBodies of waterVariation of sunlightSeasonsPrecipitationWind MountainsLong term climate change
Biomes
Major terrestrial or aquatic life zones
Defined by regional variation of climate
Aquatic Biomes
Largest part of the biospherePhotic zone (sunlight)Aphotic zone (little light)Benthic zone (bottom)Detritus (decaying matter)Turnover (circulates oxygen)
Aquatic Biomes
LakesWetlandsStreams and riversEstuaries Intertidal zonesOceanic pelagic zoneCoral reefsMarine benthic zone
Lakes
Wetlands
+/- water
Streams and rivers
Estuaries
Transition between river and sea
Intertidal zones
Tides 2x a day
Oceanic pelagic zone
Open bodies of ocean
Coral reefs
Marine benthic zone
Bottom of oceanMinimal sun
Terrestrial Biomes
Tropical rain forestSavannaDesertChaparralTemperate grasslandsTemperate deciduous forestTemperate evergreen forestTundra
Tropical rain forests
Large amounts of rain per yearRichest ecosystemContains ½ of the world’s
speciesSA,Africa, & southeast Asia
Savanna
Open, few treesSeasonal rains (75-125 cm/yr)Africa Lions, elephants
Desert
Interior of continentsDry, less than 25 cm/yr rainfall
Chaparral
Coastal regionsWet winters
Temperate grasslands
Prairies, grasslandsHerds of grazing mammalsNot as abundant
Temperate Deciduous forest
Deciduous: hardwoodsWarm summers, cool wintersNE US, Canada,
Temperate evergreen forest
Cold wintersLong dry seasonsWestern US
Tundra
Grassland few treesLittle rain/snowDeer, elk, moosePermafrost