Presentation on theme: "OBJECTIVE 14 Trace biogeochemical cycles through the environment, including water, carbon, oxygen, and nitrogen Relating natural disasters, climate changes,"— Presentation transcript:
1OBJECTIVE 14Trace biogeochemical cycles through the environment, including water, carbon, oxygen, and nitrogenRelating natural disasters, climate changes, nonnative species, and human activity to the dynamic equilibrium of ecosystemsDescribing the process of ecological succession
3The Water Cycle CONDENSATION PRECIPITATION: Water vapor in the atmosphere condenses to form clouds.PRECIPITATION:Water falls to the Earth’s surface in the form of precipitation (rain or snow).EVAPORATION and TRANSPIRATION:Remaining water is heated by the sun and reenters the atmosphere by evaporation….ORSome seeps into the soil becoming part of groundwater. Water is taken up by the roots of plants, passes through the plants, and reenters the atmosphere by transpiration (evaporation from leaves).
6The Carbon Cycle Carbon gas is in the atmosphere. PHOTOSYNTHESIS: Carbon dioxide in the air or dissolved in water if used in by plants, algae, or bacteria in photosynthesis and then release oxygen back into the atmosphere.RESPIRATION, COMBUSTION, OR EROSIONRespiration: All living organisms use take in oxygen for respiration and release carbon dioxide back into the atmosphere.Combustion: Carbon returns to the atmosphere through combustion or burning of wood or fossil fuels.Erosion: As limestone erodes, the carbon becomes available to other organisms.
8The Oxygen Cycle Oxygen is in the atmosphere. Respiration: ALL living things take in oxygen from the atmosphere and release carbon dioxide.Photosynthesis: Plants take in carbon dioxide and release oxygen back into the atmosphere.
10The Nitrogen CycleN2 (nitrogen gas) makes up about 78 percent of the atmosphere.Nitrogen fixation: Nitrogen-fixing bacteria that live in the soil take nitrogen from the atmosphere and change it to a form that organisms can use (ammonia or NH3).Ammonification: Bacteria produce ammonia from decaying matter.Nitrification: Nitrate is produced from ammonia by the nitrogen-fixing bacteria.Assimilation: Plants absorb nitrogen and use it to form organic compounds.Denitrification: Nitrate is converted to nitrogen gas and release back into the atmosphere.Organisms eat the plants, and the get rid of the nitrogen in the form of waste. The nitrogen returns to the soil.
13Natural disastersHurricanes, Tornadoes, Fires, Landslides, Floods, Droughts, etc.Can wipe out entire populations within an ecosystemCan sometimes move entire populations to a new location
14Climate changesOrganisms must adapt to new climates or migrate to a new location to survive
15Nonnative species Interrupting the food chain Habitat degradation Diseases
16Human activity Human-induced environmental changes Acid Rain Caused by coal-burning power plants (sulfur combines with water vapor in the atmosphere to produce sulfuric acid)Dying lakes and damaged forests due to pH acidity in the environmentOzone HoleAllows more ultraviolet radiation to read Earth’s surface causing an increase in human diseases such as skin cancer, cataracts, and cancer of the retinaMajor cause: CFCs (chlorofluorocarbon chemicals) found in coolants in refrigerators and air conditioners, aerosol propellants in spray cans, plastic-foam cups and containers; use is now limited
17Human activity Human-induced environmental changes Global Warming Large increase in carbon dioxide in the Earth’s atmosphere related to burning of fossil fuels that has accompanied forest clearing and urban industrializationCaused by the greenhouse effect – chemical bonds in the carbon dioxide molecules absorb solar energy as heat radiates from the Earth trapping the heatChemical PollutionIndustrial and Agricultural
18Human activity Human-induced environmental changes Loss of Resources Extinction of speciesDestruction of habitatsLoss of TopsoilTurning over to eliminate weedsAllowing animals to overgraze ranges and pasturesPoor land managementGround-water pollution and depletionWasted on watering lawns, washing cars, leaky and inefficient faucets and toiletsPolluted by irresponsible disposal of chemical wastes
19Human activity Human-induced environmental changes Human Population Growth