September 23 rd 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; 2 nd 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 – 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

3-5 Field research vs lab research Baseline for nature Technologies!!AircraftSatellitesCameras 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, I’ll go over completion terms