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Human Impact on the Biosphere

Human Impact on the Biosphere. Those Pesky Humans!. Humans have a large impact on the environment and the organisms we share it with. This is due to our Ever increasing population size. Ever increasing use of both renewable and non-renewable resources. The Carbon Cycle.

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Human Impact on the Biosphere

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  1. Human Impact on the Biosphere

  2. Those Pesky Humans! • Humans have a large impact on the environment and the organisms we share it with. • This is due to our • Ever increasing population size. • Ever increasing use of both renewable and non-renewable resources.

  3. The Carbon Cycle • Carbon cycles through the environment mainly in the form of CO2 and carbohydrates. • Photosynthesis is the main process that removes carbon from the atmosphere. • Cellular respiration is the main process that releases carbon into the atmosphere.

  4. What processes remove carbon dioxide from the atmosphere? • Photosynthesis by land and aquatic autotrophs • Precipitation onto land & ocean

  5. What processes release carbon dioxide into the atmosphere? • Cellular respiration by autotrophs & heterotrophs. • Decomposition of organisms • Volcanic activity • Human activities - mining, cutting and burning forests, and burning fossil fuels

  6. What stores carbon dioxide? • Limestone (calcium carbonate) rock • Decomposition of organisms and their conversion into fossil fuels • Diffusion of carbon into the ocean

  7. The Carbon Cycle http://www.windows.ucar.edu/earth/climate/images/carboncycle.jpg

  8. Human Activity and the Carbon Cycle • Human activity is releasing CO2 and other related forms of carbon into the atmosphere at a much faster rate then they are absorbed. • This is due to the ever increasing rate at which we: • Clear-cut and burn forests for housing and farming • Burn fossil fuels • These activities have resulted in a global climate change .

  9. What is the Greenhouse Effect? • The greenhouse effect is the rise in temperature that the Earth experiences because certain gases in the atmosphere ,water vapor, carbon dioxide, & methane (CH4) in particular, trap energy out going heat. • Without these gases, heat would escape back into space and Earth’s average temperature would be about 60ºF colder. • Because of how they warm our world, these gases are referred to as greenhouse gases.

  10. So then what is Global Warming? • The Greenhouse Effect and Global Warming are NOT the same thing!!! • Global Warming is the increase in the average measured temperature of the Earth's near-surface air and oceans. • Global Warming affects the Greenhouse Effect. • Greenhouse Effect = GOOD • Global Warming = BAD

  11. http://www.darlington.gov.uk/NR/rdonlyres/2091F156-0B6A-456B-B5FA-24579F372F36/0/greenhouseeffect.jpghttp://www.darlington.gov.uk/NR/rdonlyres/2091F156-0B6A-456B-B5FA-24579F372F36/0/greenhouseeffect.jpg

  12. Possible Effects of Global Warming • These include: • Flooding of coastal areas. • Increased spreading of disease. • Drought across inland areas. http://www.greatdreams.com/flood/flood-antigo-2004b.jpg http://www.nytimes.com/2007/07/04/us/04drought.html?_r=1&oref=slogin http://www.michigan.gov/images/mosquito_65147_7.jpg

  13. Acid Rain • The burning of fossil fuels also releases nitrogen and sulfur compounds into the atmosphere. • These compounds combine with water vapor in the air to produce acids. • The acids then migrate for miles and fall as acid rain.

  14. http://www.greeneducation.org.hk/English/focus/wpe28.gif

  15. Effects of Acid Rain • Causes acidification of lakes and streams which affects aquatic ecosystems. • Contributes to the damage of trees/plants by acidification of soils. • In addition, acid rain accelerates the breakdown of building materials, paints, statues, and sculptures that are part of our cultural heritage.

  16. http://www.newsroom.ucr.edu/releases/images/257_3.gif

  17. The Ozone Layer • The ozone layer (O3), found in the stratosphere, protects us from UV light. • UV light causes cancer, eye damage, and can damage plant tissue. http://images.google.com/imgres?imgurl=http://www.ec.gc.ca/ozone/DOCS/KIDZONE/images/ozn_layr.gif&imgrefurl=http://www.ec.gc.ca/ozone/DOCS/KIDZONE/EN/ozoneupthere.cfm&h=425&w=301&sz=78&hl=en&start=3&tbnid=NL-HDAmXoPwZ2M:&tbnh=126&tbnw=89&prev=/images%3Fq%3Dozone%2Blayer%26gbv%3D2%26svnum%3D10%26hl%3Den%26safe%3Dactive

  18. The hole in the ozone layer – South Pole There is currently a large hole in the ozone layer over Antartica. http://www.solstation.com/stars/ozo-hole.jpg

  19. What Destroys the Ozone Layer? • Chlorofluorocarbons (CFC’s) are broken apart by UV light. This causes a chain of chemical reactions that results in ozone being broken apart. • CFC’s were used in aerosol cans, and as coolants in freezers and air conditioners. They are now banned, but some are still used in less developed areas. • Even with decreased use of CFC’s it will take another 50 years before the hole in the ozone layer begins to shrink and disappear.

  20. Biological Bioaccumulation • Biological Bioaccumulation occurs when pesticides build up in animal tissue as you move up a food chain.

  21. Biological Accumulation • http://techalive.mtu.edu/meec/module02/BioconcentrationandBioaccumulation.htm

  22. DDT in Borneo • DDT was used in Borneo to kill mosquitoes. Lizards ate the mosquitoes. Cats ate the lizards. Cats began dying. • With no cats, the rat population grew. • Rats began spreading disease. • They came up with an interesting solution…..

  23. Parachuting Cats http://imagecache2.allposters.com/images/pic/ARG/21033~Parachute-Cats-Posters.jpg

  24. DDT in the United States • DDT was used to kill mosquitoes. • DDT bioaccumulated and was found in high levels in the bald eagle. • DDT caused the birds to lay eggs with pores in their shells. • When the parent birds sat on the eggs, the eggs broke. • Our national bird almost went extinct.

  25. DDT is still in the environment despite the fact that the last time it was sprayed was over 20 years ago.

  26. Threatening Biodiversity There are 4 basic ways that human actions threaten biodiversity: • Introducing non-native species • Hunting organisms to extinction • Introducing toxins into the environment • Habitat destruction

  27. Biodiversity is important because…….

  28. Many medicines come from nature • We get digitalis, a heart medication, from foxglove. • We get Taxol, the cancer fighting chemical, from Pacific yew.

  29. Imagine the possible undiscovered medical miracles that could be hiding in the areas/species that have not been studied yet.

  30. Most crop plants have wild relatives with useful traits. We will visit this “library” when we need genes to improve our crop plants. We get genetic diversity

  31. Ecosystems are more stable Ecosystems with more organisms are more stable (or homeostatic).

  32. Summary Humans Affect the Biosphere in 4 Essential Ways: A. Global Climate Change and Acid Rain B. The Ozone Layer C. Biological Magnification/Bioaccumulation D. Threatening Biodiversity

  33. What can you do to help? Are your actions sustainable?

  34. References http://www.environmentaldefense.org/images/issue_photo_12.jpg http://www.ghgonline.org/images/fire.jpg http://www.crh.noaa.gov/iwx/wxpics/flooding/woodburnaug01.jpeg http://dep.state.ct.us/burnatr/wildlife/kids/images/kpmsqui2.gif http://www.epa.gov/sunwise/images/ozone.gif http://images.encarta.msn.com/xrefmedia/sharemed/targets/images/pho/000f1/000f1c7d.jpg http://www.anselm.edu/homepage/jpitocch/genbios/54-25-DDTInFoodChain-L.jpg http://www.americanroyalarts.com/library/FC12.jpg http://www.fws.gov/endangered/photos/bird/baldeagle_in_snow.jpg

  35. References http://www.botgard.ucla.edu/html/botanytextbooks/economicbotany/images/Digitalis/Digitalisflowers.jpg http://www.agen.ufl.edu/~chyn/age2062/lect/lect_28/40_07.GIF http://www.answers.com/main/content/wp/en-commons/b/bc/Rainforest_Fatu_Hiva.jpg http://oceanworld.tamu.edu/students/coral/images/coral_reef_1.jpg http://www.geo.msu.edu/geo333/images/slide1-R-corn.JPEG

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