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Environmental Challenges. Important dates for the environment. Today the earth is changing. Speed of environmental changes has increased dramatically over the past 20 years We have seen an increase in fire risk to the boreal forest, drought, flooding and severe storms. - PowerPoint PPT Presentation
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Environmental Challenges
Important dates for the environment
Today the earth is changing• Speed of environmental changes
has increased dramatically over the past 20 years
• We have seen an increase in fire risk to the boreal forest, drought, flooding and severe storms.
• Tropical disease has migrated pole ward. And a huge increase in skin cancer.
• The natural environment has given way to human use as we over populate the planet.
Canada’s Arctic• Sea ice is shrinking:
– Leading to the potential extinction of polar bears
• Low ice flow prevents them from hunting the seals
– Arctic communities have sinking shorelines
– Other nations are going after previously inaccessible resources
• United States, Russia, Denmark and Norway want to tap the rich oil and natural gas deposits
– Increased shipping in the Northwest passage
• Counties are questioning our claim to sovereignty in the arctic.
Growth and sustainability
CoverageOceans
Arable land
Forest and woodlands
Meadows and pastures
Land that supports lit -tle or no life
• Feeding the population– 70% of water is used in
agriculture– Deforestation
• Cleared for farmland• Cities expanding on previous
farmland• Energy source
– Genetically modified food– Garbage
• Landfills are overflowing• Pollution is sinking in to
ground water
Water Basics • People
– Require 1.8l of water a day• State of the worlds water:
– 2.5% of worlds water is fresh of that 70% is in ice caps and glaciers. 0.3% is in lakes and rivers the rest is in ground water
• Drainage basins– (watersheds) are areas that when
water falls on the ground it will all move into the same river system.
• Water table – is the level at which a person must
dig down to reach the water. Wells take ground water and cause the water table to lower and well to dry up.
• Aquifers – are areas of porous material that are capable of supplying large
amounts of ground water normally has flowing water under some pressure
• Springs & artesian wells – are created if there is enough pressure behind the aquifer to push
water to the surface with out using a pump.
• Water use today: – Industry
• slowly being reduced due to new technology
– Agriculture • by far the largest user of
water for irrigation.– Domestic
• amounts continue to rise and put huge strain on water supply in areas that are heavily populated.
Water Usage
IndustryAgricultureResidential
Conserving our water• Domestic conservation will
reduce the load on water in populated areas – with new low flow fixtures, night
time watering of plants, and common respect for water.
• Raise the cost of water will reduce the waist of companies and businesses.
• Save & reuse more drain water.
• Line & cap canals, to reduce seepage and evaporation.
• Build dams: – although they have huge environmental problems like: loss of habitat,
pollution from decaying material or contamination for material in the ground. Destruction of fish hatching areas. They do increase recreational opportunities & limit flooding.
• Build desalinization plants: – currently cost is 10times that of traditional water
supply so it is not practical for most areas.
Water Use By Nations
Angola,
Cambodia,
Rwanda H
aitiChina UK
Brazil
Canad
a
Mexico
Austrail
iaUSA
World pove
rty th
reshold
0100200300400500600
Water Use Liters
Water Use Liters
Water Pollution
Degradation of water quality due to biological chemical and physical criteria.
• Types of H2O pollution:– Oxygen demanding waste (sewer
and dead waste)
• Pathogenic Organisms: (disease causing) micro organisms. Fecal coli form bacteria.
• Nutrients (phosphorus and nitrogen) Cause algae to grow.
• Oil Exxon Valdez• Toxic substances: heavy metals, &
hazardous chemicals
• Sediments: reduces quality of H2O
• Thermal pollution: water coolant
Point and Nonpoint SourcesNONPOINT SOURCES
Urban streets
Suburban development
Wastewater treatment plant
Rural homes
Cropland
Factory
Animal feedlot
POINT SOURCES
Treatment of pollution:
– Buffer zones around rivers lakes and water sheds.
– Sewage treatment facilities for sewage and city runoff.
– Government regulations on shipping and manufacturing.
– Education of public: waste disposal and product use.