lithosphere lecture
- 1. Earth’s Lithosphere “In the developed world. . We no longer honor our relationship to the soil. . . Soil has simply become one more resource - a substance necessary for crop production and for holding up buildings. . . “ (Elena Wilken. . . World Watch article, 1995)
- 2. Let’s start with the Lithosphere 3 major zones of Earth: Core - very hot, solid & liquid Mantle - solid zone, largest (68% of its mass, rich in iron, silicon, oxygen & Magnesium Crust - outermost & thinnest portion, consists of continental crust (29%) & oceanic crust (covers 71% of Earth’s surface)
- 5. Plate Tectonics and Macroevolution – The continents are not locked in place. • They drift about Earth’s surface on plates of crust floating on a flexible layer called the mantle. – California’s infamous San Andreas fault • Is at a border where two plates slide past each other.
- 6. KQED Quest: Hayward Fault http://www.kqed.org/quest/television/the-hayward-fault-pr
- 7. About 250 million years ago • Plate movements formed the supercontinent Pangaea. • Many extinctions occurred, allowing survivors to diversify.
- 8. About 180 million years ago • Pangaea began to break up, causing geographic isolation & new species
- 9. Tectonic Movement is A Natural Part of Planet, but Can we predict earthquakes? http://www.kqed.org/quest/television/earthquakes-breaking
- 10. Earth’s Lithosphere Crust contains 8 elements make up 98.5% of weight of Earth’s crust (O, Si, Al, Fe, Ca, Na, K, Mg) –Minerals (any naturally occurring inorganic substance found in Earth’s crust as a crystalline solid) –Nonrenewable fossil fuels –Potentially renewable soil nutrients (eroded rock, mineral nutrients, decaying organic matter, water, air & living organisms)
- 11. Earth’s “continental crust” Earth’s land surface: –Only 11% arable (useable for agriculture) •Rest too nutrient poor, cold, wet, dry, etc. –Possible to add 24% more to arable land category if we irrigate & use fertilizers –Total to possibly 35% of land surface potentially arable
- 12. Element = Carbon Carbon is essentialessential to life as we know it Carbon is the basic buildingbasic building blockblock for all organic compounds necessary for life (carbohydrates, proteins, fats, DNA) To study life is to study Carbon Chemistry!
- 13. Organic Compounds Compounds which contain : – C (Carbon) combined with : – H (Hydrogen – O (Oxygen) – N (Nitrogen) – S (Sulfur) – P (Phosphorus) – Cl (Chlorine) – F (Fluorine) All other compounds are called inorganic compounds
- 14. Carbon CycleCarbon Cycle It involves naturalnatural processes A global gaseous cycle (atmospheric cycle in which a large portion of a given element (C) exists in gaseous form (C02) in atmosphere Nutrients (like Carbon) are recycledrecycled in various chemical forms (cyclic movement of carbon in different chemical forms) C cyclescycles from the abioticabiotic environment to the livingliving organisms and back to the abioticabiotic environment
- 15. Re-Draw the Carbon Cycle Into Your Notes Now
- 16. CARBON DIOXIDECARBON DIOXIDE C02 Cycles fairly rapidly from the atmosphere, through soil and organisms, and back to atmosphere Key component of nature’s thermostat If too much C02 removed from atmosphere, the atmosphere will cool If cycle generates too much C02, the atmosphere will get warmer So C02 does affect the BIOSPHEREBIOSPHERE ( and can determine temperature & possibly changetemperature & possibly change climateclimate)
- 17. Some CO2 is utilized to produce biomassbiomass in trees and plants Which can form fossil fuelsfossil fuels after millions of years of decomposition and compaction (as buried organic material) When fossil fuels (coal, oil,gas) go through combustioncombustion (burning process), CO2 is released back into the atmosphere
- 18. Terrestrial producersproducers (green plants and trees) remove CO2 from the air PHOTOSYNTHESIPHOTOSYNTHESIS takes place 6CO2 + 6H2O + solar energy is converted into C6H12O6 (glucose)+ 6O2 (oxygen) ConsumersConsumers and decomposersdecomposers breakdown glucose (consumption) and utilize oxygen for respiration The Hydrocarbons get converted back to CO2back to CO2 in the atmosphere
- 19. Humans and causes of increases in CO2 (all unsustainable practices): Cut down treestrees (producers of oxygen and users of CO2) Industries Transportation (i.e.,cars) Buildings
- 20. Increased amounts of carbon: Global warming (rising sea/water level) May lead to extinction of certain plants, insect and animals, which could cause an imbalance in the food chain. Acidification on oceans
- 22. There are three types of C Cycles AtmosphericAtmospheric cycle HydrologicalHydrological cycle SedimentarySedimentary cycle carbon dioxide dissolved carbonate and bicarbonate carbon containing minerals in rocks
- 23. Discuss as a team: Should we, as individuals &Should we, as individuals & as a country, go on a carbonas a country, go on a carbon diet? What does this mean?diet? What does this mean? A huge amount of carbon isA huge amount of carbon is sequestered in tropical forests.sequestered in tropical forests. What does this mean and whyWhat does this mean and why should we care about thisshould we care about this information?information? Should we pay a carbon tax toShould we pay a carbon tax to save tropical forests? Why orsave tropical forests? Why or why not?why not? Write responses in Your journals!
- 24. Science News Reading Activity Read the article “Soils Hidden Secrets” (Charles Pet tit) We will have a QUIZ on Wednesday – You may use HANDWRITTEN notes, but you may not use the printed article or typed notes.