1 / 43

WHAT IS ENVIRONMENTAL SCIENCE?

WHAT IS ENVIRONMENTAL SCIENCE?. IS IT?. A stream flowing through a wilderness area? A rainforest canopy alive with blooming flowers? OR Your backyard?. ANSWER: ALL OF THE ABOVE. It is more than you see—it is a complex web of relationships that connects us with the world we live in

erasto
Télécharger la présentation

WHAT IS ENVIRONMENTAL SCIENCE?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. WHAT IS ENVIRONMENTAL SCIENCE?

  2. IS IT? • A stream flowing through a wilderness area? • A rainforest canopy alive with blooming flowers? OR • Your backyard?

  3. ANSWER: ALL OF THE ABOVE • It is more than you see—it is a complex web of relationships that connects us with the world we live in • It is the natural world + things produced by humans

  4. ENVIRONMENTAL SCIENCE: Study of how humans interact with the environment GOAL OF ENVIRONMENTAL SCIENCE: Understand & solve environmental problems ENVIRONMENTAL SCIENCE

  5. HOW IS THIS DONE? • Env. Scientists study 2 main types of interactions btwn humans & environment • How we use natural resources (water, plants, etc) • How our actions alter our environment

  6. Environmental Science is an interdisciplinary science (involves many fields of study) • Env Scientist investigates how the nesting behavior of bees is influenced by human activities such as the planting of suburban landscaping.

  7. Ecology: study of how living things interact with each other and with their nonliving environment • Ecologist studies the relationship btwn bees & the plants bees pollinate

  8. WHAT IS MEANT BY: SCIENTISTS AS CITIZENS, CITIZENS AS SCIENTISTS? ???

  9. ENVIRONMENT THROUGH HISTORY • A. HUNTER-GATHERERS • B. THE AGRICULTURAL REVOLUTION • C. THE INDUSTRIAL REVOLUTION

  10. HUNTER GATHERS • People who obtained food by collecting plants & by hunting wild animals or scavenging their remains • Small groups of people that migrated from place to place as different types of food became available • Affect Environment— • Spread plants to areas where plants did not originally grow • In N. Am. a combination of rapid climate change & over huntingmay have lead to disappearance of some larger mammal species ( giant sloth, giant bison, mastodon)

  11. AGRICULTURAL REVOLUTION • Eventually hunter-gather groups began to collect seeds of plants & domesticated some of the animals • This allowed human populations to grow @ unprecedentated rate • An area of land can support up to 500x as many people by farming as it can by hunting-gathering • As pop. grew conc. in smaller areaspressure on local env. • Changed food we eat (domesticated vs. wild species) • Farmland destroyed habitat • Slash-and-burn agriculture • Replacing forest with farmland on large scale soil loss, floods, water shortage

  12. INDUSTRIAL REVOLUTION • Mid 1700’s • Involved shift from energy sources (animal muscle to fossil fuels, oil, coal) • Changed society greatly: ↑ efficiency of agriculture, industry, & transportation • Introduced many + changes • Light bulb, ↑ sanitation & medical care • Also came new env. problems • Artificial substances (plastics, artificial pesticides & fertilizer) in place of raw animal & plant

  13. Most modern env. problems began during Industrial Revolution • This photograph was taken in 1968 by the crew of Apollo 8. • Photographs such as this helped people realize the uniqueness of the planet we share.

  14. E A R T H • Earth is essentially a closed system • Closed System: the only thing that enters Earth’s atmosphere in LARGE amts is ENERGYfrom the SUN & the only thing that leaves in LARGE amts. is HEAT

  15. PROBLEMS WITH A CLOSED SYSTEM • 1. Some resources are limited As pop grows ↓ Resources will be used more rapidly ↓ • 2. Chance that we will produce more waste more quickly than we can dispose of

  16. Most Environmental Issues Can Be Grouped Into 3 Categories • 1. RESOURCE DEPLETION • 2. POLLUTION • 3. LOSS OF BIODIVERSITY

  17. 1. RESOURCE DEPLETION • Natural Resource: any natural material used by humans • Renewable: • Non-renewable:

  18. Renewable & Nonrenewable Resources

  19. Renewable & Nonrenewable Resources

  20. 1. RESOURCE DEPLETION • Natural Resource: any natural material used by humans • Renewable: can be replaced relatively quickly by natural processes (fresh water, air, soil, trees, crops) • Non-renewable: sources that form at much slower rate than the rate consumed (minerals, fossil fuels) • Once used up- will take millions of yrs to replenish • Depletion: a large fraction of resources that have been used up Deforestation: trees harvested faster than they grow

  21. 2. POLLUTION • Pollution: an undesired change in air, water, or soil that adversely affects the health, survival, or activities of humans or other organisms • 2 TYPES of POLLUTANTS • 1. Biodegradable Pollutants: pollutants that can be broken down by natural processes. • Ex: human sewage, newspapers • Only a problem if they accumulate faster than they can be broken down • 2. Nondegradable Pollutants: pollutants that CAN’T be broken down by natural processes • Ex: Mercury, lead, some types of plastic • B/c don’t break down easily can build up to dangerous levels in env.

  22. 3. LOSS OF BIODIVERSITY • Biodiversity: number & variety of species that live in an area. • Extinction is a natural process • Only limited info about how modern extinction rates compare with those of other periods in Earth’s history • All species have economic, scientific, aesthetic, recreational value…so it is important to preserve them

  23. THE ENVIRONMENT & SOCIETY • How does a society use/share a common resource? • A neighborhood park? • Open ocean?--- not owned by any nation YET • People from many countries use the ocean for fishing & transportation

  24. “TRAGEDY OF THE COMMONS” • 1968- ecologist Garrett Hardin published essay “Tragedy of the Commons” Described the attitude with which people use resources & became the theoretical backbone of the environmental movement A common theme is the idea of bioethics

  25. “TRAGEDY OF THE COMMONS” • Hardin argued: Main difficulty in solving environmental problems is the conflict between short-terminterests of individuals AND long termwelfare of a society

  26. “TRAGEDY OF THE COMMONS” • To illustrate his point he used example of the commons • Commons: area of land that belonged to the whole village

  27. “TRAGEDY OF THE COMMONS” • It was in best short-term interest of an individual to put as many animals as possible “If I don’t use this resource, someone else will” HOWEVER If too many animals grazed on the commons animals destroy grass now everyone suffered EVENTUALLY • Commons were replaced by closed fields owned by individual who were careful to prevent overgrazing

  28. POINT OF HARDIN’S ESSAY? • Someone or some group has to take responsibility for maintaining a resource • If no one takes that responsibility the resource can be overused & become depleted

  29. WHAT HARDIN DID NOT CONSIDER • Social nature of humans- we live in groups & depend on one another • We can solve environmental problems by planning, organizing, considering scientific evidence, proposing a solution • The solution may override interests of indivual in short term BUT improves environment for everyone in long term

  30. Earth’s Natural Resources are our modern “COMMONS”

  31. ECONOMICS & THE ENVIRONMENT • In addition to social pressures—economic forces influence how we use resources A. Supply & Demand B. Cost & Benefits C. Risk Assessment

  32. SUPPLY & DEMAND • When the demand for a product increases while the supply remains fixed, the cost of the product will increase. • Ex.: if the supply of oil decreases: 1. Pay higher price 2. Use less oil 3. find new sources of energy

  33. COST & BENEFITS • Cost of environmental solutions can be high • Cost-benefit analysis: balances the cost of action against the benefits one expects from it. • To INDUSTRY: the cost of pollution control may outweigh the benefits BUT • To a nearby COMMUNITY: benefits may be worth the higher price

  34. RISK ASSESSMENT • Tool that helps us to create cost-effective ways to protect our health & environment • One of the costs of any action is the risk of an undesirable outcome

  35. DEVELOPED vs. DEVLOPING COUNTRIES

  36. DEVELOPED vs. DEVLOPING COUNTRIES • Environmental problems in developed countries tend to be related to consumption • In developing nations, the major environmental problems are related to population growth

  37. WHAT DO YOU THINK THE ENVIRONMENTAL PROBLEMS OF EACH COMSUMPTION PATTERN ARE?

  38. Consumption Trends • Ecological Footprint: shows the productive area of Earth needed to support one person in a particular country • For a person in a developed country –the ecological footprint is an avg. 4x as large as a person in a developing country • Developed nations use ~ 75% of the world’s population, even though they make up only ~ 20% of the world’s population.

  39. Critical Thinking • Environmental Problems are complex • Balance between rights of individuals/property owners and society as a whole • Be careful when reading about issues for “BIAS”

  40. Bias in Environmental Issues • Passion for cause may lead to distortion of facts • Political clout may oversimplify environmental impact • Media sensationalizes issues • Learn to think critically, consider the source, listen to many viewpoints

  41. SUSTAINABILITY

More Related