APES review topics

1. APES review topics

2. Cycles • All nutrients on earth have to cycle: matter is neither created nor destroyed. • All nutrients pass through both living and non living components of the ecosystem • Living things need all nutrients and can only get them through consumption (animals) or uptake (plants) • Nitrogen cycle is driven by bacteria • Hydrologic cycle is driven by the sun, water vapor • Carbon cycle: greenhouse effect, carbon sequestration.

3. Soils • O layer- organic material, decaying life • A layer- topsoil, humus • B layer- subsoil, some broken parent material • C layer- parent material bedrock • Infiltration: the downward movement of water through soil. • Leaching: dissolving of minerals and organic matter in upper layers carrying them to lower layers. • The soil type determines the degree of infiltration and leaching. • Sand- 0.05-2 mm • Silt- 0.002-0.05 mm • Clay- less than 0.002 mm • Soil nutrients are determined by the type of vegetation which is determined by the climate

4. Weathering and erosion • Soil erosion lowers soil fertility and can overload nearby bodies of water with eroded sediment. • Sheet erosion: surface water or wind peel off thin layers of soil. • Rill erosion: fast-flowing little rivulets of surface water make small channels. • Gully erosion: fast-flowing water join together to cut wider and deeper ditches or gullies. • Soil erosion is the movement of soil components, especially surface litter and topsoil, by wind or water. • Soil erosion increases through activities such as farming, logging, construction, overgrazing, and off-road vehicles. • Desertification- land becoming more desert like due to soil erosion • Weathering- biologic, chemical and mechanical • Weathering is the breaking apart of rock material into smaller particles

5. Global warming • Proxy Data • Ice cores, Tree Rings and Lake Core Sediments • major factors shape the earth’s climate: • The sun. • Greenhouse effect that warms the earth’s lower troposphere and surface because of the presence of greenhouse gases. • Oceans store CO2 and heat, evaporate and receive water, move stored heat to other parts of the world. • Natural cooling process through water vapor in the troposphere (heat rises). • Between 1979 and 2005, average Arctic sea ice dropped 20% • If seas levels rise by 9-88cm during this century, most of the Maldives islands and their coral reefs will be flooded. • “global warming” refers to the current increase in global temperatures which is suspected to be caused by anthropogenic sources (cars, factories, etc)

8. Plate tectonics

9. The Earth’s Major Tectonic Plates

10. Spreading center Ocean trench Oceanic tectonic plate Oceanic tectonic plate Plate movement Plate movement Tectonic plate Oceanic crust Oceanic crust Subduction zone Continental crust Continental crust Material cools as it reaches the outer mantle Cold dense material falls back through mantle Hot material rising through the mantle Mantle convection cell Mantle Two plates move towards each other. One is subducted back into the mantle on a falling convection current. Hot outer core Inner core Collision between two continents

11. EURASIAN PLATE NORTH AMERICAN PLATE ANATOLIAN PLATE CARIBBEAN PLATE JUAN DE FUCA PLATE CHINA SUBPLATE ARABIAN PLATE PHILIPPINE PLATE AFRICAN PLATE PACIFIC PLATE SOUTH AMERICAN PLATE NAZCA PLATE INDIA-AUSTRALIAN PLATE SOMALIAN SUBPLATE ANTARCTIC PLATE Convergent plate boundaries Transform faults Divergent plate boundaries

12. Benefits of the ocean • Great diversity- coral reefs • Coral bleaching- waters getting too warm causing coral (animals) to die leaving behind only the white limestone • Coral reefs protect main land from high surf and storms. • Huge amount of carbon sequestration • estuaries are where rivers meet the sea. Help control flooding, very productive ecosystem. • Filter toxic pollution, excess plant nutrients, sediments and other pollutants.

13. Ozone depletion • How to make ozone: • O2 + High Energy UV  O + O • O2 + O  O3 • CFC’s – chlorofluorocarbons • Stratospheric ozone depletion • Harmful effects of less ozone: • Melanoma • Basal Cell Carcinomas • Squamous Cell Carcinomas • Other Skin Damage • Cataracts and Other Eye Damage • Immune Suppression • Inhibit photosynthesis in plankton

15. Air pollution • Carbon oxides- incomplete combustion of carbon-containing materials. • 93% of carbon dioxide (CO2) in the troposphere occurs as a result of the carbon cycle. • 7% of CO2 in the troposphere occurs as a result of human activities (mostly burning fossil fuels). • Nitrogen oxides- nitrogen and oxygen gas in air react at the high-combustion temperatures in automobile engines and coal-burning plants. • Sulfur Oxides- 2/3 come from coal and oil combustion • SO2 in the atmosphere can be converted to sulfuric acid (H2SO4) and sulfate salts (SO42-) that return to earth as a component of acid deposition.

16. Air Pollution • Suspended particulates (SPM) • The most harmful forms of SPM are fine particles (PM-10, with an average diameter < 10 micrometers) and ultrafine particles (PM-2.5). • Troposphere Ozone- highly reactive gas, major component of photochemical smog. • UV + VOC = NOx = Ozone • NOx: Released mainly from burning of fossil fuels • VOCs: emitted in gasoline fumes, and in the evaporation of solvents • Nitrogen dioxide- A brown gas which contributes to urban haze • Can be converted in the atmosphere to HNO3 which then is deposited as acid deposition

17. Water pollution