September 23rd Remember – no school Thursday, pep rally Friday

Test Tuesday Chapter 3 Ecosystems: What are they and how do they work?

42 M/C

1 Short Response

1 Graphic Interpretations (w/ 7questions)

Core Case Study

Tropical Rainforests

Near Earth’s equator

Incredible variety of life

Warm year round, high humidity, heavy rainfall

Cover ~2% of earth’s land surface; contain up to ½ of known terrestrial plant and animal species

Core Case Study

What’s going on in the TRF?

½ of forests destroyed or disturbed

Cut down trees, growing crops, grazing cattle

Why care?

Reduce earth’s vital biodiversity, early extinction

Accelerate atmospheric warming b/c no trees to absorb CO2

Change regional weather patterns in ways that could prevent the return of TRF

What Keeps Us and Other Organisms

Alive?

What are specific aspects of the Atmosphere described in 3-1?

Troposphere – closest, air we breathe – but 78% is Nitrogen; 21% oxygen

Greenhouse gases, absorb and release energy that warms us

Stratosphere – ozone filters 95% of UV radiation

3-1

Specifics of hydrosphere?

All water on or near earth’s surface

Water vapor in atmosphere; liquid water on surface and underground; ice – icebergs, glaciers, ice in frozen soil (permafrost)

Oceans are 71% of surface; 97% of the water

3-1

Specifics of geosphere?

Core, mantle, crust

Nonrenewable fossil fuels and minerals

Renewable soil chemicals

3 key factors

One way flow of high-quality energy from sun, through living things in their feeding interactions, into environment as low-quality energy (heat), back to space as heat

Cycling of nutrients

Gravity

3-2 Major Components

Ecology

Levels – organism, population, communities, ecosystems, biosphere

Abiotic vs biotic

Feeding/trophic levels

Basic equation for photosynthesis

3-2

Photosynthesis vs chemosynthesis

Consumers – primary, secondary, herbivores, carnivores, omnivores

Decomposers vs detritivores

3-3 Happens to Energy?

Food chain vs food web

Energy flow; 2nd law of thermodynamics – energy transfer through food chains and webs is not very efficient b/c some usable energy is degraded and lost as heat

GPP and NPP

Swamps/marshes, TRF have highest NPP for terrestrial

Estuaries for aquatic ecosystems

3-4 Happens to Matter?

Hydrologic

Collects, purifies, distributes

Powered by sun

Evaporation, precipitation, transpiration (water evaporated from surface of plants – 90% of atmospheric water)

Surface runoff; seep into soil – aquifers

Small amount ends up in living components

3-4

Hydrologic

Purification – removes impurities

Streams/lakes & aquifers – filtration; bacteria too

ONLY about 0.024% of water is available to humans as liquid freshwater

Our affects: withdraw large amounts; clear vegetation; increase flooding when drain/fill wetlands

3-4

Carbon

Building block – carbohydrates, fats, proteins, DNA

Cycle is based on CO2

In atmosphere, crucial for thermostat

Removed by producers

Used in cellular respiration by consumers; decomposers

3-4

Carbon Cycle

We alter by:

add large amounts of CO2 to atmosphere by burning fossil fuels

Clear vegetation that could remove it

3-4

Nitrogen cycle (refer to last Friday’s ppt)

Nitrates – usable form for plants

We affect it:

Add large amounts of NO when burn fuels

Add N2O through action of anaerobic bacteria using inorganic or organic fertilizer

Release stored nitrogen through destruction of forests

Upset in aquatics – add excess nitrates

Remove N from topsoil with crops

3-4

Phosphorus Cycle – never in atmosphere

Phosphate salts in rock formations and seafloor

Erosion and water carry to soil to be used by plants

Producer, consumers, decomposers

Limiting factor for plants

We remove from some soils, add to others, excess gets into aquatic ecosystems

3-4

• sulfur – mostly stored in soil, rocks, fossil fuels

Sulfur – our affects:

Release large amounts of sulfur dioxide when burn coal/oil, refine sulfur containing oil, extract metals from sulfur containing compounds when mined

3-5Field research vs lab research

Baseline for nature

Technologies!!

Aircraft

Satellites

Cameras

Remote sensing

Geographic information systems

GPS

Google maps/earth

True/False review wkst

True:

1, 3, 5-8, 11,12,14, 17-19, 21-24, 26-29

I’ll go over completion terms