Presentation on theme: "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."— Presentation transcript:
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)
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)
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.
About 250 million years ago Plate movements formed the supercontinent Pangaea. Many extinctions occurred, allowing survivors to diversify.
About 180 million years ago Pangaea began to break up, causing geographic isolation & new species
Tectonic Movement is A Natural Part of Planet, but Can we predict earthquakes? http://www.kqed.org/quest/television/earthquakes- breaking-new-ground http://www.kqed.org/quest/television/earthquakes- breaking-new-ground
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)
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
Element = Carbon essential Carbon is essential to life as we know it basic building block Carbon is the basic building block for all organic compounds necessary for life (carbohydrates, proteins, fats, DNA) To study life is to study Carbon Chemistry!
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
Carbon Cycle natural It involves natural processes A global gaseous cycle (atmospheric cycle in which a large portion of a given element (C) exists in gaseous form (C0 2 ) in atmosphere recycled Nutrients (like Carbon) are recycled in various chemical forms (cyclic movement of carbon in different chemical forms) cycles abioticliving abiotic C cycles from the abiotic environment to the living organisms and back to the abiotic environment
CARBON DIOXIDE C0 2 Cycles fairly rapidly from the atmosphere, through soil and organisms, and back to atmosphere Key component of nature ’ s thermostat If too much C0 2 removed from atmosphere, the atmosphere will cool If cycle generates too much C0 2, the atmosphere will get warmer BIOSPHERE temperature & possibly change climate So C0 2 does affect the BIOSPHERE ( and can determine temperature & possibly change climate)
biomass Some CO2 is utilized to produce biomass in trees and plants fossil fuels Which can form fossil fuels after millions of years of decomposition and compaction (as buried organic material) combustion When fossil fuels (coal, oil,gas) go through combustion (burning process), CO2 is released back into the atmosphere
producers Terrestrial producers (green plants and trees) remove CO2 from the air PHOTOSYNTHESI PHOTOSYNTHESIS takes place 6CO2 + 6H2O + solar energy is converted into C6H12O6 (glucose)+ 6O2 (oxygen) Consumersdecomposers Consumers and decomposers breakdown glucose (consumption) and utilize oxygen for respiration back to CO2 The Hydrocarbons get converted back to CO2 in the atmosphere
Humans and causes of increases in CO 2 (all unsustainable practices): trees Cut down trees (producers of oxygen and users of CO2) Industries Transportation (i.e.,cars) Buildings
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
There are three types of C Cycles Atmospheric Atmospheric cycle Hydrological Hydrological cycle Sedimentary Sedimentary cycle carbon dioxide dissolved carbonate and bicarbonate carbon containing minerals in rocks
Discuss as a team: Should we, as individuals & as a country, go on a carbon diet? What does this mean? A huge amount of carbon is sequestered in tropical forests. What does this mean and why should we care about this information? Should we pay a carbon tax to save tropical forests? Why or why not? Write responses in Your journals!
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.