Ecosystems

Community Interactions

• What is a food web?• How does energy move

thru a food web?• What is the role of

decomposers?• Predict what would

happen if one of these species became endangered or wiped out.

Watch…

• NASA – The Ocean A Driving Force for Weather and Climate

https://www.youtube.com/watch?v=6vgvTeuoDWY

http://www.bing.com/videos/search?q=Jet%20Stream%20Animation%20el%20nino%20and%20la%20nina&qs=n&form=QBVR&pq=jet%20stream%20animation%20el%20nino%20and%20la%20nina&sc=0-21&sp=-1&sk=#view=detail&mid=FF4D8AD21FFDF74BD002FF4D8AD21FFDF74BD002

Biodiversity

• Species rich in an ecosystem, biome, or Earth• Measure of health• Endangered species & extinction threaten

Biodiversity

Influences on Ecosystems

Biotic Factors• Biological, living, factors• Birds, trees, mushrooms,

bacteria

Abiotic Factors• Physical, nonliving factors• Temp, ppt, humidity

Competitive Exclusion Principle

Warblers are birds. Different species of warblers can live in the same tree. Can different species occupy the same niche? Explain

Niche• An organism’s job or role

in its ecosystem• Place in the food web• Type of food it eats• How obtains food• Predator/prey

relationships• Physical conditions for

survival (ie/ adapting to temp & weather changes)

Climate• Avg pattern of weather

patterns in a region• Trapping of heat by

atmosphere• Latitude – angle of heating

– Polar, temperate, tropical zones

• Transport of heat by winds & ocean currents

• Amount of precipitation

Heat Transport =unequal heating of the Earth’s surface

Winds• Warm air rises

– Near equator rises

• Cool air sinks– Near poles sinks

• Upward & downward movt create winds

• Winds move heat from regions of sinking air to rising air affecting climate

Currents• Cold water near poles sinks

& flows along ocean bottom• Cold water rises as heats in

warmer regions– Upwelling

• Water flow creates currents• Ocean currents warm/cool

the air above

Global Climate Zones

Effects on Climate

Greenhouse Effect• Rise in temp due to trapped

gases & energy from sun (water vapor, carbon dioxide)

• W/o heat would escape into space (60* colder)

Global Warming• Avg inc in Earth’s temp

(1.4*f rise in past 100 years)• Rise in temp due to human

activities• Effects rainfall patterns,

sea-lvl, plants, animals, humans

Global warming debateAlthough still a controversial subject, there is a growing consensus that global climate changes are being caused by

environmental pollution, especially by greenhouse gases.

Do we need to take more urgent action to halt this trend?

Community Interactions

• Competition – organisms try to use same resource at same time– Competitive exclusion principle• Direct competition – winner & loser• No 2 sp can occupy the same niche at the same time

• Predation – predators seek prey– Anglerfish & Nemo

• Symbiosis – species live closely together

Symbiotic Relationships

• Mutualism – (+/+)– Both benefit– Shark & remora

• Commensalism – (+/0)– One benefits, other not effected– Whale & barnacle

• Parasitism – (+/-)– One benefits, other harmed– Dog & tick

Biomes are classified by…• Climate of the region• Where biome is found & geography• Special adaptations of the vegetation• Types of animals found; physical & behavioral

adaptations to env’t

What is a biome?

• Lg area of distinct plants & animals• Consists of many ecosystems• All living things are closely related to their

env’t• Changes can cause a ripple effect on other

parts (volcano eruption, forest fire, el nino)

Biomes

Tropical Rainforest• Most diverse biome• Hot/wet year-round; humid• Found around the eqtr• Lg diverse trees & plants

Tropical Dry Forest• Seasonal rainfall; intense

dry season• Deciduous trees• Warm year-round• Mexico, C. America

Biomes

Tropical Savanna / grassland• Tropical wet / dry• More rain than desert• Isolated trees; covered by

grass• Africa

Desert• Dry, less than 25 cm rain • Extreme temp changes – no

veg to maintain heat• US, Africa, Asia, etc• Death Valley

Biomes

Temperate Grassland• Rich mix of grasses

prairies• Most fertile soils• Prone to fires• Omaha, Nebraska

Temperate Woodland• Chaparral (dominated by

shrubs)• Mix of shrubs & open woods• Semi-dry & low-plants fire

prone• Los Angeles

Biomes

Temperate Forest• Deciduous forest,

coniferous also• US!!• Seasons, winter cold, halts

plant growth

NW Coniferous Forest• Moist air, cool air• Washington• Variety of conifers & trees

(Giant redwood)• Moss covers floor & trunks

Biomes

Boreal Forest / Taiga• Dense evergreen coniferous

forests, • Northern; Alaska• winters bitterly cold,

thawing in summer

Tundra• Permafrost – perm frozen

soil• Short cool summer, long

winters• Thawing & freezing cycles

destroys plants• Alaska

Biomes

Freshwater• Ponds, lakes, streams,

rivers, wetlands• Freshwater• Wetlands have highest

species diversity

Brackish

• Estuaries, wetlands, rivers• Partial fresh & salt water• Streams/rivers merge w/ocean• Chesapeake Bay

Biomes

Marine• Oceans, coral reefs, estuaries• Covers ¾ earth’s surface• Supply most of world’s O2

supply• Zonation – 4 areas each w/

great sp diversity (shore – deepest)