human environment by hmharky

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									Human-Environment Interaction
Outline: • Conceptual framework and terminology • Human-Atmosphere Interactions • Human-Lithosphere Interactions • Human-Hydrosphere Interactions
• Policy Issues, Prospects, and Perspectives

Conceptual framework and terminology
• Cultural-Physical Landscape Interactions

Cultural Landscape

Physical Landscape

• Terminology
– Environment

– Biosphere (Ecosphere) … atmosphere, hydrosphere, lithosphere

Human-Atmosphere Interactions

Human-Atmosphere Interactions
• Control Factors for Climate • Climatic regions and historical development patterns • Biome – desert, grassland, steppe, tropical rain forests, northern coniferous forests. • Ecosystems

Human-Atmosphere Interactions

Human-Atmosphere Interactions (cont.)
• Natural- vs. Human-induced climate changes • Aerosols and the icebox effect
– Volcanoes / Smoke stacks

• Global Warming, Acid Rain, Ozone Depletion

Human-Atmosphere Interactions

Global Warming -- “greenhouse” effect
• Industrial revolution • Greenhouse gases
– carbon dioxide, methane, nitrous oxides, chlorofluorocarbons.

• Greenhouse effect • Secondary effects
– sea level rise, increasing aridity or dry areas, extremal weather patterns, crop yields and the distribution of agric. lands

• Counterarguments

Human-Atmosphere Interactions

Acid Rain
• low altitude vs. high altitude pollutants • volcanoes / smoke stacks (fuel consumption) • sulfur dioxide/nitrous oxide
• acid rain (precipitation)

sulfuric/nitric acid
[pH<5.6]

• geographic extent
• effects
– statues/buildings, forests, water bodies and fish, crop yields.

Human-Atmosphere Interactions

Ozone Depletion
• Upper vs. lower level atmospheric ozone • Low: photochemical smogs / car pollution • Upper:
– blocks UV radiation (DNA effects)

– CFC and chlorine/oxygen interaction

• Effects
– immune system, skin cancer, crop damage, forest damage, phytoplankton kills.

• Montreal Protocol

Human-Lithosphere Interactions

Human-Lithosphere Interactions
• Critical roles of the lithosphere
– surface reflectivity/solar radiation

– water balance – temperature and region- to global-scale climate – methane, carbon dioxide, and carbon sink.

• Major human-induced changes
– tropical deforestation, desertification, soil erosion

Human-Lithosphere Interactions

Tropical deforestation
• Total forest cover (30%); Tropical Forest (6%) • Tropical forest processes
– oxygen/carbon balance
– surface/air temperature; moisture/reflectivity – biodiversity

– regulates watersheds/ water flow

Human-Lithosphere Interactions

Tropical deforestation (cont.)
• Human-induced changes and problems
– population pressure

– agriculture – fuel and lumber – burger and steaks

• Scale
– 45% degraded globally – Africa (50%), Asia (50%), Central America (70%), South America (40%)

Human-Lithosphere Interactions

Desertification
• Arid/semi-arid regions
• Process
– plants removed water/wind erosion pavement – increased surface water runoff; declining sub-surface water.

• Causes
– Natural versus human – overgrazing, deforestation, clearing for cultivation, burning.

• Scale (900 million people; 1.2 billion hectares)
– Africa (40%), Asia (33%), Latin America (20%)

Human-Lithosphere Interactions

Desertification (cont.)
• Scale
– 900 million people; 1.2 billion hectares. – Africa (40%), Asia (33%), Latin America (20%)

– Severe cases: Algeria, Ethiopia, Iraq, Jordan, Lebanon, Mali, and Niger.

Human-Lithosphere Interactions

Soil Erosion
• Top soil and lithosphere
• Soil composition and formation
– rock inorganic mineral, organic matter, organisms, air, and water – decomposing rock and decaying organic matter – tends to increase in depth over time.

• Human-induced erosion • Mitigating factors

no agriculture.

– rotation, fallowing, and terracing.

Human-Lithosphere Interactions

Soil Erosion (cont.)
• Scale
– Global issue – Severe cases: Guatemala, El Salvador, Turkey, Haiti, China.

– “A Worldwatch Institute report of the mid-1980s projected a 19% decline in cropland per person between that time and the end of the century. But, ominously, it also projected - at then current rates of soil loss and population growth - a 32% reduction in topsoil per person by the year 2000. Current evidence confirms those predictions, with profound implications for food production trends and for economic and political stability in the world.”

Human-Hydrosphere Interactions

Human-Hydrosphere Interactions
• Critical roles of the hydrosphere
– hydrologic cycle – renewable resource

– life sustaining – agriculture and industry; constraint on development.

• Major human-induced changes
– regional supplies, silt loads, pollution, algae.

Human-Hydrosphere Interactions

• Water pollution
– wastewater treatment – 90% of sewage untreated in developing countries
– India (70%), China (80% of rivers), Taiwan, Malaysia, Hong Kong, Eastern Europe and Russia.

Solid, Hazardous, and Toxic Waste

• Solid Waste (municipal solid waste - MSW)
– history of solid waste – 200 million tons per year/ 3.5 pounds per day
– proportional to population and per capita income.

• Landfills
– open versus sanitary

– 75% of U.S. waste; declining availability – Fresh Kills, Staten Island

Solid, Hazardous, and Toxic Waste

• Incineration
– 20% of U.S. solid waste/ 125 incinerators – waste-to-energy
– dioxin, acid gases, heavy metals.

– Japan, 75% of solid wastes

3x dioxin levels.

• Ocean Dumping
– history – “sustainable yield” – scale of problem

Solid, Hazardous, and Toxic Waste

• Toxic Wastes
– toxic - death or serious injury to humans or animals – hazardous - immediate or long-term human health risk.
– 10% of industrial waste materials.

– ground water and air pollution.

• Radioactive Wastes
– Low-level (100 years) versus high-level (10,000-240,000 years) – “spent fuel” – disposal sites and problems.

Solid, Hazardous, and Toxic Waste

• Exporting Wastes
– New York (3,774,000 tons) – Illinois (2,800,000 tons) – California (453,183 tons) PA, VA, OH, CT VT, MA (0.16 mil tons) IN, WI MO, IA, IN, WI (1.3 mil. tons) NV, WA

Prospects

• Our perpetual dilemma lies in the reality that what we need and
want in support and supply from the environments we occupy generally exceeds in form and degree what they are able to yield in an unaltered state. • This final chapter detailing a few of the damaging pressures placed upon the environment by today’s economies and cultures is not meant as a litany of despair. Rather it is a reminder of the potentially destructive ecological dominance of humans.


								
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