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Lecture

PS 2235 E- Lecture 4

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Department
Political Science
Course
Political Science 2137
Professor
Ross Gibbons
Semester
Fall

Description
Politics of the Environment--PS 2235 E Lecture # 4 The Lungs of the Earth POLITICS OF THE ENVIRONMENT 1. Trees and the ecosystem --the lungs of the earth --green plants are the producers of life in the ecosystem: transferring energy through photosynthesis from physical to biological parts of the system; oxygen is produced; our atmosphere was created by green plants --trees anchor, hold soil --trees provide habitat --trees are a source of food, shelter and many other products --trees release water through transpiration (1 tree puts out 000's of gallons water in a day) --since 8000 BC billions of acres of forest and woodland have been lost to agriculture 2. Temperate: trees which survive in a seasonal climate --have evolved to survive in changing conditions; hardy resilient; --97% of the nutrients necessary for new growth are in the soil --in Canada: we have 10 major climate zones with a vast number of species --197 deciduous species --128 broad/narrow leaf coniferous (evergreen) species 3. Tropical: trees which survive in a relatively constant climate --less ability to survive change (acclimatation) --less history of being under siege from harvesting --tropical forests store 90% of their nutrients in the vegetation removed during deforestation --conditions for tropical forest regeneration: most species are pollinated by birds, insects, animals...often just one or a few species; soils and nutrients are easily washed away...tree seedlings are sensitive to changes in temperature, humidity, light 4. Definitions: Deforestation: a complete change in land use from forest to agriculture (does not include forest left to regrow even if clearcut) Degradation: a process that describes human-induced phenomena which lower the current and/or future capacity of the soil to support human life (classed as light, moderate, severe, extreme) 5. Regeneration: --requires loose, reasonably fertile soil --seed sources from nearby stands of trees --diverse species of pollinating and seed-dispensing birds, insects and mammals --freedom from recurrent fires, pollution and other destruction 6. The Retreating Rainforest: --'If the Amazon is the lungs of the world, then the debt is its pneumonia' --deforestation in Brazil, Costa Rica, India, Mynamar, the Philippines, Vietnam has accelerated and since 1992 has been known to be much worse than originally thought --Agent Orange: only we can prevent forests --tropical/rainforest harvesting has been increased dramatically: 51 million acres per year which is a 79% increase about the loss rate of 1980...this is being driven in domestic politics by repayment conditions for debt (World Bank, IMF) and by the demands of population growth --the greenhouse effect: forests act as 'sinks' for absorbing C02 so the fewer the trees, the less carbon is removed from the atmosphere; burning wood emits CO2, methane and nitrous oxide...all of which are present in greater amounts in the atmosphere...if the current emissions and deforestation continue for 40 years: we will see a temperature climb of 3 - 8 degrees Fahrenheit --flooding: undisturbed forest absorbs 35% of rainfall; partially logged absorbs 20%; planation land only 12 %...serious flood in the Phi
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