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