Ecology and the BiosphereEcology and the Biosphere
Chapter 52
Earth from the moonEarth from the moon
Ecology Ecology
Ecology is the study of Distribution and Abundance of organisms over time.
Distribution is where we naturally find / found an organism
Abundance is how many individuals are / were counted at the study sites
Fig. 52-2Fig. 52-2
Organismalecology
Populationecology
Communityecology
Ecosystemecology
Landscapeecology
Globalecology
Ecological levelsEcological levels Populations include all the members of one species
in a given area and time. Species include all of the potentially interbreeding
populations. Community includes all of the different species
(plants, animals, fungi, etc.) living in the area Ecosystem includes the Biotic and Physical
components of the environment Landscape- Interactions between connected
ecosystems Biosphere is world –wide issues, like Global
warming, and pollution
ClimateClimate
Determines what plants can grow thereTwo major factors of climate:
– Temperature (warm to cold)– Precipitation (moisture – wet to dry)
Position on globe determines climate
TemperatureTemperature
Simple gradient from warm to cold by increasing latitude
Solar intensity greatest and warmer at equator (0o)
Less intense and cooler at poles (90o).
Solar radiationSolar radiation
Solar radiation around the Globe
Solar radiation around the Globe
PrecipitationPrecipitation
Alternating bands of wet and dry areas along a latitudinal gradient
Wet at equator 00, and 600 N / SDry at 300, and 900 poles
– Poles are frozen desertsCaused by formation of Hadley Cells
Hadley CellsHadley Cells
Air rises (00, 600) due to warming of surface.
– as the air rises it becomes less dense and cooler, dropping water as rain.
Air falls (300, 900 poles) – air becomes compressed, and heats. It
absorbs moisture and falls as dry air.
Global air circulation, precipitation, and winds: Hadley cellsGlobal air circulation, precipitation, and winds: Hadley cells
Convection CurrentsConvection Currents
Global air circulation is affected by the properties of air water, and land.
Figure 5-5Figure 5-5
Global Air CirculationGlobal Air Circulation
Hadley cell
West Coast LatitudesWest Coast Latitudes Dry : nearer 300
– San Diego=32.5; LA= 34; Sta. Barbara= 34.5
– Santa Cruz =37, SF 37.75; – Eureka= 40.75
Wetter nearing 600:
– Portland= 45.5; Seattle= 47.5 – Juneau= 58; Anchorage = 61
Hadley - Ferrel cellsHadley - Ferrel cells
Coriolis EffectCoriolis EffectGlobal air
circulation is affected by the rotation of the earth on its axis.
Figure 5-4Figure 5-4
Prevailing windsPrevailing winds
These Hadley cell wind currents move North or South
The spinning of the earth makes it seem like they come at an angle.– In CA our winds, storms usually come from
the south west.– Our Rains often bring warmer weather
Global Trade Wind PatternsGlobal Trade Wind Patterns
Ocean currentsOcean currents Prevailing winds cause ocean waters to
move in the prevailing direction. Northern Pacific flows clockwise
– Sea level 4 feet higher in Asia Water flows from Alaska southwards along
our coast Near shore upwelling brings cold, nutrient
rich water up along our shore – Very high productivity of tidal areas
Ocean CurrentsOcean Currents
Wind from the north starts surface ocean water moving
Earth's rotational force deflects moving water westward
c. Deep, cold watermoves up to replacewater moving west
Upwelling
SeasonsSeasons
Caused by tilting of earth on its rotational axis.– Intensity of sunlight varies.– Most extreme at poles– Little change at equator.
Seasons- Seasons-
Tilting of earth moves solar equator. Effectively moves solar 300 dry zone
north in summer The wet belt moves farther south
giving us wet winters
Causes of SeasonsCauses of Seasons
BiomesBiomes
Major vegetation types that also determine the animal community present.
Determined mostly by climate – Soil also important factor
Common California Biomes Common California Biomes Dry to WetDry to Wet
Desert - driestChaparral – shrubs with fire cycleGrasslands – no trees, all grassSavanna – widely spaced trees in grassWoodland – open canopyForest – closed canopy, wettest
A climograph for some major kinds of ecosystems (biomes) in North AmericaA climograph for some major kinds of ecosystems (biomes) in North America
BiomesBiomes
Major BiomesMajor Biomes
Patterns of distribution in the biospherePatterns of distribution in the biosphere
Coniferous forest, Lady Bird Grove (top left), Sequoias (right), rain Coniferous forest, Lady Bird Grove (top left), Sequoias (right), rain forest (bottom left)forest (bottom left)
Temperate deciduous forest, Great Smokey Mountains National ParkTemperate deciduous forest, Great Smokey Mountains National Park
Tropical forestsTropical forests
SavannaSavanna
Desert. Organ Pipe State Park (top), Joshua Tree National Park (bottom left), Desert. Organ Pipe State Park (top), Joshua Tree National Park (bottom left), Death Valley (bottom right)Death Valley (bottom right)
Temperate grassland- PrairieTemperate grassland- Prairie
Tundra. Denali National Park (left), reindeer (right)Tundra. Denali National Park (left), reindeer (right)
Rain shadow Rain shadow Precipitation increases as storms are
pushed up over mountains.– accordingly rain becomes snow – As air moves up slope in the Sierras it
cools 3-5 degrees per 1,000 ft. This is the same effect as moving 300 miles
farther north ! Causes deserts in Nevada
Most islands with mountains have wet and dry sides
RainshadowRainshadow
RainshadowRainshadow
Biotic Zonation of SierrasBiotic Zonation of Sierras
Summer FogSummer Fog
Summer Fog Summer Fog – Inland air warms quickly. This rising air, pulls in
coastal air.– Marine air is pulled inland by this draw in the
Central valley – causing summer winds over the low passes (Altamont)
– Cold water off CA. coast cools incoming warm, moist ocean air- causing condensation.
Essential for ranges of Coast Redwoods, relic pines and cypress species .
Can add up to 10 inches of summer precipitation in some areas.
FOG HEAVEN / The sun will come out tomorrow. Or maybe not. It's summer in the city, and that means gray skies.
What causes fog. Chronicle Graphic
Central Valley SmogCentral Valley Smog
: weblog.rudayday.com/archives/2005_08.html
Smog moves up into SierrasSmog moves up into Sierras
Temperature Inversion layersTemperature Inversion layers dense air flows downhill and collects in low spots,
valleys. Great Central valley is an example.– This dense air may be blocked by hills etc. from warmer
winds which blow over the top of dense air, leaving it alone.
– Dense tule fog may form for days. Inversion layer (cold air higher up) also traps
pollutants. Mexico City problems Reno, Tahoe now ban fireplaces.
Often “burn off” in summer but leave the haze of phytochemical smog behind.
Ocean ZonesOcean ZonesIntertidal – species rich zone on rocks
between high and low tides levels.Photic – upper sunlit layers where
phytoplankton (producers) liveNeritic – productive zone over
Continental ShelfOceanic - Open Ocean, nutrient poor
low productivity