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ENVIRONMENTAL ISSUES

ENVIRONMENTAL ISSUES. Only when the last tree has died and the last river poisoned and the last fish been caught will we realise that we cannot eat money. Cree Indian Proverb. ECOLOGICAL FOOTPRINTS. EF is a measure of human demand on Earth’s ecosystems

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ENVIRONMENTAL ISSUES

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  1. ENVIRONMENTAL ISSUES Only when the last tree has died and the last river poisoned and the last fish been caught will we realise that we cannot eat money. Cree Indian Proverb

  2. ECOLOGICAL FOOTPRINTS • EF is a measure of human demand on Earth’s ecosystems • The area of land needed to provide necessary resources and absorb the wastes generated by a community • Mathias Wackernagel

  3. ECOLOGICAL FOOTPRINTS • Concept of EF --> Bill Rees and Mathis Wackernagel (1992)

  4. EF analysis approximates the amount of ecologically productive land, sea and other water mass area required to sustain a population, manufacture a produce, or undertake certain activities • Looks at our use of energy, food, water, building material and other consumables

  5. Calculations used are typically converted into a meausre of land area ‘global hectares (gha) per person • Coverted to number of planets • There is avg. of 1.9 ha of land for each person • Human footprint has exceeded biocapacity of earth by 25% • On average people have EF of 2.3 • We would need 1.4 planets to sustain this use • US - EF over 12 (need over 6 planets) • China & India growth rates --> need 25 planets by 2050

  6. Ecological deficit / reserve : The difference between the biocapacity and EF of a region or country • An ecological deficit occurs when the Footprint of a population exceeds the biocapacity of the area available to that population.

  7. Global overshoot - occurs when human demand on nature exceeds the biosphere’s supply or regenerative capacity • Such overshoot leads to a depletion of Earth's life supporting natural capital & a build up of waste

  8. At the global level, ecological deficit & overshoot are the same, (no net-import of resources to the planet) • Local overshoot occurs when a local ecosystem is exploited more rapidly than it can renew itself

  9. Solutions WATER FOOD GARBAGE ECOLOGICAL FOOTPRINT HOUSING TRANSPORTATION ENERGY

  10. LAND DEGRADATION • Is any deterioration of the productive capacity of soil for either present or future use Types of land degradation • Erosion • Chemical deterioration • Physical deterioration • Desertification

  11. EROSION • Removal of nutrient-rich layer of topsoil by wind or water • Water erosion - can occur anyway tends to be worse in areas with higher rainfall • Wind erosion --> common in arid or semi-arid climates

  12. EROSION • Mature forest (void of human activities) --> topsoil loss b/t 0.004 & 0.05 tones per ha per year (4-40 kg) • Cultivated land (NA and Europe) erosion 17 tonnes per hectare per year • Increase --> change from forest to farmland • Asia, Africa & S. America - 30-40 tonnes per hectare by per year

  13. Terrain Deformation • Large or small gullies may cut into farmer’s field • Landslides (mass movements of land) • Landslide • quebec

  14. Terrain Deformation • Dunes, deflation hollows • Land overblown (with materials form somewhere else)

  15. Chemical Deterioration • Deterioration of soil as result of leaching, salinization, acidification or pollution • Nitrogen, phosphorus & potassium - loss from soil in one of 2 ways • Areas of high precipitation - nutrients washed away or leached (occurs in Canada but more serious in tropical areas)

  16. Chemical Deterioration • Problem in Asia, Africa and S.America --> forests cleared for farming • For a few years farm yields are high because some organic materials remain in soil (Leaching eventually destroys fertility of soil

  17. Chemical Deterioration

  18. Chemical Deterioration • Salinization - increase in the concentration of soluble salts in soil • Salts becomes toxic for plant growth

  19. Chemical Deterioration • Salinization can occur naturally if water table is close to to surface in an arid area • Can be greatly accelerated by excessive irrigation • 1/8th of all irrigated land in the world has be degraded by sever salinization (1/3rd somewhat affected • Problem in drier parts of US, China, Australia & Middle East

  20. Physical Deterioration caused by compaction, waterlogging,or subsidence. • Occurs in 3 ways – • soil can be compacted by the use of heavy machines or by the trampling of herds or animals • waterlogging – when floods recede from an area • physical damage from sinking of the land which can be caused when a significant amount of water is removed from the water table

  21. Physical Deterioration

  22. Physical Deterioration

  23. Desertfication Occurs when human activities reduce the productivity of an arid or semi-arid area to the point that is resembles a desert • 40% of world has climates dry enough that they face possibility of desertification • Put over 1 billion people at risk

  24. Human Causes of Land Degradation • Deforestation • Overgrazing • Unsustainable agriculture • Overuse of natural vegetation • Urban/industrial pollution

  25. Deforestation • Land is cleared for agricultural use (tropical rainforests) • Soil is exposed to serious erosion and leaching

  26. Deforestation

  27. Deforestation in Canada • One case of deforestation in Canada is happening in Ontario's boreal forests, near Thunder Bay, where 28.9% of a 19,000 km² of forest area had been lost in the last 5 years and is threatening woodland caribou. This is happening mostly to supply pulp for the facial tissue industry. • In Canada, less than 8% of the boreal forest is protected from development and more than 50% has been allocated to logging companies for cutting.

  28. Deforestation in Canada

  29. Overgrazing • Too many grazing cattle, sheep, or goats can destroy vegetation beyond its ability to recover --> erosio and leaching

  30. Unsustainable Agriculture • Intensive agriculture doesn’t allow soil to renew itself • In dry areas --> salilnization • Agricultural mining --> not sustainable • Monoculture (one crop) Ex. Prairies during 1930’s • Soil may degrade --> loss of vital structure provided by organic matter (even if fertilizers used)

  31. Will Agriculture meet our demand for food • What will happen if we run out of fertile agricultural land

  32. Overuse of Natural Vegetation • Developing parts of the world - people rely on trees, shrubs for fuel and bdg materials • If density of pop. is too high may have impact similar to that of overgrazing and deforestation

  33. Urban/industrial Pollution • Pollution can foul soil or adjacent farms and make land unusable • Soil contamination caused by the presence of man-made chemicals or other alteration in the natural soil environment --> arises from the rupture of oil tanks, application of pesticides, oil & fuel dumping, leaching of wastes from landfills or direct discharge of industrial wastes to the soil.

  34. 1995 Causes of Land Degradation by Area (in %)

  35. Impact of Land Degradation Is there a correlation between land degradation and poverty and conflict???

  36. During the 1980’s and 1990’s, famines that killed tens of thousands of people were routinely blamed on drought and civil wars. • Rarely did observers acknowledge the contribution of land degradation to these tragedies.

  37. Is this because scientists find other issues more interesting to study, or that research funding is more readily available for studies in more “trendy” areas???

  38. Impacts • Land Loss from Production – • 50 000 – 70 000 square kilometres land lost to erosionPLUS20 000 – 30 000 square kilometres land lost to salinization and water logging • So that means, that land degradation takes between 70 000 – 100 000 square kilometres of land out of production per year

  39. Impacts • The growth of cities means an additional 20 000 – 40 000 square kilometres are lost from production each year. • To put these amounts in context, the area of New Brunswick is about 73 000 square kilometre

  40. Overgrazing • Too many grazing cattle, sheep or goats --> destroy vegetation beyond its ability to recover • Soil is exposed to serious erosion and leaching

  41. http://www.ted.com/index.php/talks/alex_steffen_sees_a_sustainable_future.htmlhttp://www.ted.com/index.php/talks/alex_steffen_sees_a_sustainable_future.html

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