Unit 6: Terrestrial & Aquatic Diversity Chapter 6 & 7

• Chapters 6 & 7

Earth has three major climate zones: Tropical, Temperate, Polar

Factors affecting climate:

Uneven heating of the earth’s surface: Rays hit equator directly &

hit poles indirectly High solar radiation increased evaporation & precipitation

Tilt in Earth’s axis Leads to seasonal changes in temp & precipitation

Rotation of the earth on its axis: winds are deflected east/west, creates global patterns of prevailing winds that distribute heat & moisture

Properties of air, water, & land: Hot air tends to rise, cool, & release moisture as precipitation; Cool air tends to sink, get warmer, & lose its moisture by evaporation, These two properties cause convection cells to circulate air, heat & moisture

Ocean currents redistribute heat & influence air

circulation; created by:

– Wind blowing over oceans

– Differences in water density

– Also mix waters & distribute nutrients

https://www.youtube.com/watch?v=KUU7IyfR34o

Winds blowing along western coasts push surface

water away from land causes upwelling: deep,

cold, nutrient-rich water rises

– Nutrients support large pops of phytoplankton zooplankton fish, birds, mammals

Coriolis Effect:

– In physics, the Coriolis effect is a deflection of moving objects when the motion is described relative to a rotating reference frame

– The Coriolis effect makes storms swirl clockwise in the Southern hemisphere and counterclockwise in the Northern Hemisphere

• https://www.youtube.com/watch?v=i2mec3vgeaI

Important Climatic Events:

– El Niňo Southern Oscillation (ENSO)

• When prevailing tropical winds blowing westward weaken or reverse

• Warms surface water along South & North American coasts suppresses normal upwellings of cold, nutrient-rich water

– Causes decline in fish species

• Can cause extreme weather in Pacific & Indian Oceans

– La Niňa

• Reverse of El Niňo

• Results in more Atlantic hurricanes, colder winters in Canada & NE U.S., and warmer/drier winters in southern U.S.

http://video.nationalgeographic.com/video/el-nino

Greenhouse effect- Greenhouse gases warm lower

atmosphere: H2O, CO2, CH4 (methane), N2O (nitrous

oxide), Gases reflect infrared radiation back to earth’s lower atmosphere

Topography (earth’s surface features) can affect climate

– Ex: Rain Shadow Effect

– Ex: Cities create microclimates: have more pollution, higher temps, & lower wind speeds

https://www.youtube.com/watch?v=DoKTTHd-XEQ

Terrestrial Diversity • Biomes vary with

– Latitude: north & south of equator

– Altitude: distance from sea level

Desert Biomes Area where evaporation > precipitation Found mostly in tropical & subtropical regions

3 types – Tropical desert:

• hot & dry most of year • Few plants • Ex: Africa’s Sahara

– Temperate desert: • Daytime temps high in

summer, low in winter • Shrubs, cacti; reptiles, birds • Ex: North America’s Mojave

– Cold desert: • Winters are quite cold,

summers are warm/hot • Ex: China’s Gobi

http://video.nationalgeographic.com/video/lizard_thornydevil

http://www.bbc.co.uk/programmes/p0037p9f bactrian camel

Terrestrial Diversity

• Desert Climate Graphs:

• Desert Adaptations:

– Succulent plants save water by having no leaves, store water in their flesh, & open stomata at night

– Evergreen plants have wax-coated leaves to save water

– Many animals are nocturnal

– Insects & reptiles have thick scales to minimize evaporation

– TED Talks:

• Ecology from the Air: http://www.ted.com/talks/greg_asner_ecology_from_the_air

• http://www.ted.com/talks/frans_lanting_s_lyrical_nature_photos

• http://www.ted.com/talks/e_o_wilson_on_saving_life_on_earth

• Grasslands Biomes

– Enough precip. for grasses, not enough for shrubs or trees

– Occur in interiors of continents

–Persist b/c of:

1. Seasonal drought

2. Grazing by herbivores

3. Occasional fires

Grasslands 3 types: Tropical grassland: Savanna

• Warm most of year; alternating dry & wet seasons • Found in Africa, South America, Australia; Acacia trees; many

herbivores like elephants, zebra, giraffes, gazelles; Animals have mass migrations to find water; plants adapted to drought, Threatened by grazing of cattle (fecal pavement)

Temperate grassland: Prairie • Daytime temps warm in summer, low in winter • Found in North America, South America, Asia • Has deep, fertile, alkaline topsoil • Grasses have thick root network • Animals include prairie dogs, bison, coyote, eagles

Cold grassland: Tundra • Most of year is cold • Has Permafrost = frozen underground soil • Hares, voles, lynx, weasel, snowy owl, fox, bears (thick fur) • Canada, Russia • There’s also the Alpine tundra – high mountains • Threatened by oil drilling & mining

Terrestrial Diversity

• Grassland Climate Graphs

Forest Biomes:

• Tropical Rain forest

• Near equator

• Year-round warm temps & high precip. (80F, 75-100 in per year)

• Dominated by broadleaf evergreen plants create canopy

• High NPP & biodiversity: Parrots, frogs, monkeys, snakes, jaguar, etc.

• Nutrient-poor, acidic soil

– Temperate Rain forest

• NW America

• Moderate temps & high precip.

• Dominated by coniferous evergreen trees (spruce, fir, redwoods)

• Lots of moss

• Relatively lower biodiversity due to limited light

• Major source for timber

• Animals: elk, weasels, owls, bear, cougar, salmon, etc.

https://www.youtube.com/watch?v=H9MV5CgPgIQ

https://www.youtube.com/watch?v=trWzDlRvv1M

https://www.youtube.com/watch?v=btM0A3jOEoc

– Temperate deciduous forest • US, Europe • Warm summers, cool winters • Dominated by broadleaf deciduous trees (oak, maple, hickory)

dormant in winter, grow leaves back each spring • Lots of birds, rodents, insect, some larger mammals (deer, skunks,

foxes, bears)

– Taiga/ Boreal forest/Coniferous

• South of arctic tundra in N. America, Europe, Asia • Warm summers, cool winters • Dominated by coniferous evergreen trees (spruce, pine, fir, cedar)

– Needles prevent water loss • Needles make soil acidic

– Slow decomp • Animals: bears, wolves, lynx, caribou, chipmunks, weasels, etc.

– Hibernate

Terrestrial Diversity

• Forest Climate Graphs

Plankton: drifting organisms

Phytoplankton Producers/Autotrophs

produce 50% of the O2 you breath everyday

Ex: Diatoms, cyanobacteria

Zooplankton consumers

Ex: rotifers, fish & crab larvae

Nekton Strong swimmers

Ex. fish, turtles, whales, adult jellyfish

Benthos Bottom dwellers

Ex. sea stars, clams, crabs, anemones

Types of Aquatic Organisms:

Limiting

Factors:

Temperature,

light,

oxygen,

nutrients,

Turbidity

(cloudiness)

http://www.planktonchronicles.org/en/episode/embryos-and-larvae

https://www.ted.com/talks/the_secret_life_of_plankton

http://education.nationalgeographic.com/education/media/plankton-revealed/?ar_a=1

*Watch short videos on plankton

Aquatic Life Zones Key factors in distribution of organisms:

1. Temperature: Decreases w/ depth

2. Availability of light for photosynthesis • Confined to Euphotic (photic) zones

• Decreases w/ depth

3. Dissolved oxygen content • Decreases with depth

4. Availability of nutrients (CO2, NO3-, PO4

3-) • CO2 increases with depth

5. Turbidity: degree of cloudiness in water • Inhibits photosynthesis

Estuaries: where fresh mixes w/saltwater

Estuaries form between Atlantic Ocean and 5 major Georgia

rivers -the Altamaha, Ogeechee, Satilla, Savannah, & St.

Mary’s

Wetlands: land covered with water all or part of year

Hydric soil -saturated by water, resulting in anaerobic conditions

Coastal Zone: Intertidal

Services: absorbs pollutants, controls flooding, storm buffer, &

provides habitat/nurseries

Watch & Answer Questions: Bill Nye wetlands

https://www.youtube.com/watch?v=k7wO3W1mWnA

Marine Life Zones:

• The Savannah River broadens into an estuary about 28 miles upstream from the Atlantic

• Sewage & industrial waste pollution

• Mercury contamination from coal fired power plants & the manufacture of chlorine

• Savannah Harbor Expansion Project (SHEP) is predicted to affect the fresh/salt water composition impacting flora & fauna

Threats:

Organisms

Adaptations

Marsh grass (spartina) & cattails

flexible stems to withstand tides, vacuoles to store salt, air spaces for oxygen transport (hydric soil not aerated), barriers to block salt

Fiddler Crab gills & a primitive lung, to breath in water & on land, burrows for escape from high tide, decrease activity level

Cypress Trees Cypress knees (provide stability)

*In general organisms will have excretory organs which remove excess salt & water

3. Coral Reefs

• Tiny animals or “polyps” secrete calcium carbonate shells

• Polyps and zooxanthellae algae = mutualism

FOCUS: Gray's Reef

- Sandstone formation (not coral) provides habitat for invertebrates: corals, moss

animals (bryozoans), tunicates (sea squirts),

sponges, & barnacles.

get O2 & chemical energy get a home & CO2 for photosynthesis

Coastal Zone: Neritic (shallow area)

Services: Biodiversity (Marine equivalent of tropical rain forests)

Provides habitat for one-fourth of all marine species

Food Recreation

Coastal Zone: Neritic-Coral Reef

Threats: Warmer ocean temperatures = coral bleaching: kills algae Increasing ocean acidity Coastal development Pollution, runoff Overfishing/ trawling Dredging Careless boat operation Ozone depletion- UV rays harm coral

*Watch short videos on ocean threats

http://www.sciencelearn.org.nz/Contexts/Life-in-the-Sea/Sci-Media/Animations-and-Interactives/Marine-ecosystem

Open Ocean/Pelagic: Three vertical zones: 1. Euphotic zone: lit upper zone

– Phytoplankton perform photosynthesis

– Nutrient levels low & d-Oxygen levels high

– Have fast swimming, predatory fish (swordfish, sharks, tuna)

2. Bathyal zone – Dimly lit, few producers, Have zooplankton and smaller fishes

3. Abyssal zone

Dark & cold, high pressure, No photosynthesis, little d- oxygen, nutrient levels vary

Deep, hot ocean vents (black smokers)

w/chemosynthetic bacteria using hydrogen

sulfide to create chemical energy

*Watch short video on abyssal creatures

http://youtu.be/FswYwyke7cc

Deep ocean vents (black smokers)

w/chemosynthetic bacteria using

hydrogen sulfide to create chemical energy

Goes down and past the continental

slope, pressure is great; food is

limited

to the debris of dead material that

sinks like snow from the above zones.

A lot of the marine fish we eat come from

pelagic fisheries (mackerel, sardine & tuna.)

Stocks have been over-exploited and some

species even face extinction due to

overfishing.

Clear, well-lit open water, large predators

Decreased light & oxygen concentrations,

Squids & swordfish

where the continental slope levels

off

http://www.untamedscience.com/biology/biomes/pelagic-biome/

https://www.youtube.com/watch?v=ufxGw8EqY5Q

• Marine Life Zones: 3 major zones

• 3. Benthic Zone: – = The Ocean Floor

• Underlies all the other zones

– Communities consist of • Bacteria • Fungi • Seaweed (algae) • Invertebrates

(sponges, echinoderms, mollusks)

• Fish

Ocean Threats : Coastal development

Habitat destruction

Overfishing, trawling

Pollution

Invasive species

Climate change &coral bleaching

Ocean acidification

Eutrophication(dead zones)

http://www.youtube.com/watch?v=Uc605ajWIBE

http://www.nbcnews.com/video/nightly-news/52403911#52403911

http://www.youtube.com/watch?v=ahOmeTOIrRg

http://www.smm.org/deadzone/what/top.html

http://i2i.stanford.edu/AcidOcean/AcidOcean3.htm

https://www.youtube.com/watch?v=Wo-bHt1bOsw

*Watch short videos on ocean threats

Ocean pH is currently around 8.1, models by end of century it may be around 7.7

Lentic (standing):

Lakes

Ponds

Lotic (flowing):

Streams

Rivers

III. Freshwater Zones

http://tdcms.ket.org/knh/loticcommunities.html

http://www.pbslearningmedia.org/resource/knh.entcomm/lenticcommunities/

Organisms & Adaptations: *interactive websites

Littoral [lit-er-uh l] zone

1. Rooted plants

2. Shallow, near shore

Limnetic zone

1. Open, away from shore

2. Photosynthetic (photic) zone

Profundal zone 1. Deep, dark 2. No photosynthesis

Benthic zone 1. Decomposers &

detritivores

4 Lake Zones (lentic):

Great Lakes -largest

supply of surface

freshwater in the world

Oligotrophic Lake Eutrophic Lake

Low nutrients

Good light penetration

High DO

Deep waters

Low algal growth

Small mouth bass, lake trout

High nutrients

Poor light penetration

Low DO

Shallow waters

High algal growth

Carp, catfish, bullhead

Cultural (artifical) eutrophication: input of excess nutrients

(fertilizers) causing excess algal growth

Aquatic Life Zones

• Lake Types Based on Nutrient Levels: – Oligotrophic lakes

• Low nutrients and low NPP

• Very clear water

– Eutrophic lakes

• High nutrients and high NPP

• Murky water with high turbidity

– Cultural (artifical) eutrophication: input of excess nutrients (fertilizers) causing excess algal growth

• Oligotrophic lake

• Eutrophic lake

• Freshwater Degradation:

–Dams destroy habitat

– Flood control levees and dikes along rivers alter flow & destroy habitat

–Pollutants from cities and farms on streams, rivers, and lakes

–Draining wetlands for agriculture & development