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Why Should You Care About the Environment?

Why Should You Care About the Environment?. Wade B. Worthen. Biology Department, Furman University, Greenville, SC. Overview: - Some facts about humans - Some facts about ecological systems - How are we doing? - Preserving forests – case studies.

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Why Should You Care About the Environment?

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  1. Why Should You Care About the Environment? Wade B. Worthen Biology Department, Furman University, Greenville, SC

  2. Overview: - Some facts about humans - Some facts about ecological systems - How are we doing? - Preserving forests – case studies

  3. Some facts about humans:A. What we use now - We are animals. We require food, clean water, and air - We use ~50% of the Earth’s land area for food production (and most of the remainder is not farmable) - We use ~50% of the Earth’s available fresh water - We use ~40% of the Net Primary Productivity (NPP is “new plant growth” – it is the base of the food pyramid for all terrestrial communities). - We are changing the climate of the planet

  4. Some facts about humans:B. Population growth1 billion: ~ 18002 billion: ~ 1927 (127 years later)3 billion: ~ 1960 (33 years later)4 billion: ~ 1974 (17 years later)5 billion: ~ 1987 (13 years later)6 billion: ~ 1999 (12 years later)2004: ~ 6.3 billion, adding 80 million each year (10 NYC’s) U.N. medium projection: 8.9 billion in 2050, almost all growth in developing, tropical countries.

  5. Some facts about humans:C. Two big questions: - (quantitative) Given our current pattern of resource use, will the Earth be able to sustain a population of 9 billion humans? - (qualitative) Will the quality of life change?

  6. Some facts about humans:C. What do we want for the future?- - - -

  7. Some facts about humans:C. What do we want for the future?- - - -

  8. Some facts about humans:C. What do we want for the future?- - - - “I want world peace…”

  9. Some facts about humans:C. What do we want for the future?- World Peace - - -

  10. Some facts about humans:C. What do we want for the future?- World Peace - - - “Democracy is the government of the people, by the people, for the people…”

  11. Some facts about humans:C. What do we want for the future?- World Peace - stable, moral governments - -

  12. Woo-hoo!! Some facts about humans:C. What do we want for the future?- World Peace - stable, moral governments - -

  13. Some facts about humans:C. What do we want for the future?- World Peace - stable, moral governments - stable, productive economies -

  14. Some facts about humans:C. What do we want for the future?- World Peace - stable, moral governments - stable, productive economies -

  15. Some facts about humans:C. What do we want for the future?- World Peace - stable, moral governments - stable, productive economies - stable, productive food supply

  16. Some facts about humans:D. How can we get there?- A stable, productive food supply Stable, productive economies Stable, productive, moral governments Peace and happiness for our children

  17. Some facts about humans:D. How can we get there?stable food supplyproductive economies Happy peoplestable, moral governmentsTo achieve ONE goal, we must achieve ALL goals...

  18. Some facts about ecological systems:A. What they do for humans:- They produce all our food - They produce and clean our water - They produce the oxygen we breathe and they clean our air.

  19. Some facts about ecological systems:B. How they do it: O2 CO2 Water Soil nutrients Filtered water

  20. Some facts about ecological systems: B.How they do it: - And different plants use slightly different resources and make different types of food.

  21. Some facts about ecological systems: C. What diversity does: - 1. Diversity increases productivity Rainforests are 4X more productive than agricultural fields; so they make more “food”, filter more water, and filter more air.

  22. Some facts about ecological systems: C. What diversity does: - 1. Diversity increases productivity Even agricultural ‘polycultures’ are more productive than low diversity ‘monocultures’. (However, they are more difficult to harvest…)

  23. Some facts about ecological systems:C. What diversity does: - 2. Diversity increases stability Monocultures are not very resistant; a single pathogen or disturbance can wipe out the entire community.- diverse systems are more stable

  24. Some facts about ecological systems:D. All species are not equal: - “Keystone” species exert a disproportionate effect on their communities

  25. Some facts about ecological systems:D. All species are not equal: - “Keystone” species exert a disproportionate effect on their communities - As species are lost, it becomes more likely that a keystone species will be lost; resulting in a dramatic further reduction in diversity and ecosystem function.

  26. Some facts about ecological systems:D. All species are not equal: Cougar Cougar Deer Deer overpopulate Plants Plants overgrazed

  27. Some facts about ecological systems:E. Some basic food-web energetics: (inefficiency) CARNIVORES HERBIVORES PLANTS

  28. Some facts about ecological systems:E. Some basic food-web energetics: CARNIVORES HERBIVORES PLANTS There is more food lower on the food chain…. Eating predators is energetically ‘wasteful’

  29. Some facts about ecological systems:E. Some basic food-web energetics: Area Effects CARNIVORES HERBIVORES PLANTS LARGE AREA OF HABITAT

  30. Some facts about ecological systems:E. Some basic food-web energetics: HABITAT FRAGMENTATION

  31. Some facts about ecological systems:E. Some basic food-web energetics: Carnivores can’t be supported; herbivores overgraze land, soil nutrients depleted. HABITAT FRAGMENTATION

  32. Some facts about ecological systems: - So if we want productive, stable ecological systems, we MUST preserve biodiversity – it is FUNCTIONALLY important.

  33. How are we doing?A. Food:- Food production per person has declined for grain (-11%), beef (-15%), and fish (-17%) since the1980’s Brown, L. (2001). Eco-economy.

  34. How are we doing?A. Food:- Food production per person has declined for grain (-11%), beef (-15%), and fish (-17%) since the1980’s - although yield/hectare increased 4X from 1950 to 1990 (“green revolution”), it is flat since then.Brown, L. (2001). Eco-economy.

  35. How are we doing?A. Food:- Food production per person has declined for grain (-11%), beef (-15%), and fish (-17%) since the1980’s - although yield/hectare increased 4X from 1950 to 1990 (“green revolution”), it is flat since then. - total meat production has increased 5X since 1950, although the population has only increased 3X. (Eating meat is LESS efficient than eating grains).Brown, L. (2001). Eco-economy.

  36. How are we doing?B. Natural Fisheries: - Global fish catch is declining by 500,000 metric tons/yr from peak in 1987 (Science, 2003). - Predatory fish (tuna, salmon) and bottom fish (flounder, sole) have decreased by 90%.

  37. How are we doing?B. Natural Fisheries: - Global fish catch is declining by 500,000 metric tons/yr from peak in 1987 (Science, 2003). - Predatory fish (tuna, salmon) and bottom fish (flounder, sole) have decreased by 90%. - Farmed salmon and trout are FED other fish, further increasing pressures on natural fisheries.

  38. How are we doing?C. Effects on Diversity: - Habitat loss and fragmentation reduce diversity

  39. How are we doing?C. Effects on Diversity: - Habitat loss and fragmentation reduce diversity - Climate change may be more important. Based on the distribution of 1,103 species ranging over 20% of the Earth’s land surface area, continued climate change may lead to the extinction of 15-37% of these species by 2050 if climatic trends continue (Thomas et al. 2004, Nature).

  40. How are we doing?D. Summary:- We need diverse ecosystems to sustain the existing human population.

  41. How are we doing?D. Summary:- We need diverse ecosystems to sustain the existing human population. - These services will be even more important as the population increases.

  42. How are we doing?D. Summary:- We need diverse ecosystems to sustain the existing human population. - These services will be even more important as the population increases. - Our current practice of over-exploitation of resources is contrary to our long-term goals.

  43. Case Studies Overview about Rainforests Preserving Biodiversity Case Studies: - Ecuador and Oil - Costa Rica and Ecotourism - Brazil: The Future of the Amazon

  44. RAINFOREST OVERVIEW General Characteristics: > 10cm rain/month, mean temp = 26oC Variable: 40 types, differing in rainfall. LA = 4m/yr; Africa = 1.5m/yr 2% of Earth’s Surface Area; 21% Earth’s NPP; 50% Earth’s species

  45. RAINFOREST OVERVIEW Form and Function: Trees 60m tall; lots of layers, 50% more biomass/unit area than deciduous forests in US Nutrients in biomass, not soil Decomposition is rapid, recycling nutrients to biomass Volatiles from trees - condensation nuclei - CAUSE rainfall A RAINFOREST FEEDS ITSELF NUTRIENTS AND WATER

  46. RAINFOREST OVERVIEW Why do you value cultural diversity? Why Do you value history and our libraries? We have areverence for uniqueness, creativity, and knowledge.

  47. PRESERVING BIODIVERSITY

  48. PRESERVING BIODIVERSITY A A A B C D E F G H A B A Fragmentation selects for generalist species that can live in variable, frequently disturbed habitats…. PRODUCES LESS DIVERSE, REDUNDANT COMMUNITIES

  49. CASE STUDIES NATURAL ENVIRONMENT HUMAN CULTURE

  50. CASE STUDIES: USA In the US, we have used our resources to power OUR OWN economic growth RESOURCES MANUFACTURING PROFITS and jobs GOODS AND SERVICES

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