Earth's Resources And Environmental Protection PDF

Earth’s Resources and Environmental Protection  When one uses the term ‘a city’s ecological footprint’, what does one refer to? ► Cities impose an environmental impact on their hinterlands ► Cities impose an environmental impact on ecosystems far beyond the immediate region. ► Citi...

Earth’s Resources and Environmental Protection  When one uses the term ‘a city’s ecological footprint’, what does one refer to? ► Cities impose an environmental impact on their hinterlands ► Cities impose an environmental impact on ecosystems far beyond the immediate region. ► Cities have must be seen as urban entities that require vast inputs and have vast outputs ► They have a massive demand on natural resources especially natural resources e.g. building materials, water, land, energy (fossil fuels) ► The more populous a city the greater the demand and therefore the ecological footprint. ► Cities are also major producers of waste!  When one uses the term ‘a city’s ecological footprint’, what does one refer to? A city’s ecological footprint may be defined as the land area and the natural resource capital on which the city draws in order to sustain its population and its production structure. Note that today’s cities (especially in MEDCs) have appropriated rural areas, not only in their own countries, but also all over the world. This is due to advancements in technology and trade. Transnational corporations have their headquarters in MEDCs but have their centres of production in LEDCs  What Is a Natural Resource? ► Something that is useful to people ► Factors that determine:  Cultural  Technological  Economic  Properties of a given resource ► Examples:  Mineral and energy resources  Air and water resources  According to Bergman and Renwick, resources have the following characteristics: ► Resources are defined by  Cultural values ► What is used and valued by people in society ► Wood, mud or brick building ► Swamps become wetlands, cultural shifts  Available technology ► Potential resources ► Ability to extract and use  Economics ► Supply and demand ► Externalities Net Oil Imports and Exports  Natural Resources ► Substitutability  Stabilizes prices  Limits resource scarcity ► Nonrenewable resources  Limited amounts ► Gas, oil, coal, metals ► Renewable resources  Replaced continually ► Air, wind, water, solar  Mineral Resources ► Metallic  Copper, lead, silicon ► Nonmetallic  Building stone, graphite, slate, quartz ► Distribution of deposits  Cartels ► Depletion and substitution  Solid Waste ► Landfills ► Incineration  Sanitary landfills  Reduces volume  Provides energy  DISPOSAL AND RECYCLING OF SOLID WASTE ► The average American throws away 2 kg of solid waste / day ► How much does your household discard daily? ► The average person now throws away twice as much, as our parents did! Why do you think this is so? ► Paper accounts or 1/3 of solid waste ► Discarded food and yard waste also 1/3 of solid waste ► 99% of all consumer goods end up in a landfill site 6 months after the date of purchase. ► In most countries on Earth solid waste is disposed of in only THREE different methods!  Each method/ way presents it’s own particular set of problems either in environmental degradation or a cost to the public!  METHODS OF SOLD WASTE DISPOSAL ► LANDFILL DISPOSAL ► INCINERATION ► RECYCLING  LANDFILL DISPOSAL ► The majority of waste in the word is trucked to sanitary landfills. ► In this method solid waste is taken to a dump and a layer of earth is bulldozed over the garbage, which is then compacted ► This method reduces the emissions of gases and odours from the decaying trash, prevents fires and discourages vermin. ► The solid waste is transported to many landfill sites surrounding cities, daily. Generally they are kept out of view of the public eye. ISSUES: ► Landfills have been closed in many countries as they contaminate groundwater, devalue property, or have been filled to capacity. ► Legislation is stringent and public opposition is high. ► As a result, landfill sites are few, filled to capacity and costly. The public is often charged a fee to use them.  INCINERATION ► This refers to the burning of solid waste materials at extremely high temperatures ► Incineration reduces bulk by ¾ and the ash requires less space to dispose. Incineration also produces energy, which boils water, creates steam and can in turn be used for electrification. ISSUES: ► Incineration releases extremely toxic substances e.g. dioxins. This enters the atmosphere and remains in the ash. ► These substances can cause respiratory diseases and illnesses. RECYCLING  METHODS OF SOLD WASTE DISPOSAL ► LANDFILL DISPOSAL ► INCINERATION ► RECYCLING  RECYCLING ► This refers to the converting of solid waste into new materials and objects. ► This reduces the need for landfill sites as well as incinerators. ► It also reuses natural resources that have already been extracted from the environment ► ISSUES: ► There are very few direct problems associated with recycling solid waste, however, there are some barriers, namely, separating waste, consumer resistance, lack of market, cost, indirect loss.  Recycling ► Reduces need for landfills and incinerators ► Reuses natural resources ► Barriers  Waste separation  Consumer resistance  Lack of market  Hidden costs  Indirect losses ► New products and technologies ► Shared costs with consumers Energy Resources ► Fossil fuels ► Solar ► Hydroelectric ► Wind ► Geothermal  ► Oil, natural gas, coal Fossil Fuels  Stored energy created over millions of years ► Nonrenewable ► Wood primary energy source until 19th century ► Oil is most important energy resource today ► U.S. and Canadian industry  Natural gas, oil, coal ► Distribution of fossil fuels  Uneven  Reserves  Oil ► Distribution  2/3 of oil reserves in Middle East  North America and Europe have highest per capita oil consumption rates ► Oil production and pricing  OPEC, 1960  Oil crises ► Future of fossil fuels  Proven reserves  Unconventional sources World Energy Resources Crude Oil Prices, 1970-2006  Renewable Energy ► Nuclear  Fission versus fusion  Problems ►Potential accidents ►Radioactive waste ►Public opposition ►High cost World Nuclear Power, 2004 US Nuclear Power  Renewable Energy ► Biomass  Burning wood, plant material and animal waste  Home heating and cooking in most of world  Brazil – fuel cars and trucks ► Hydroelectric  Flowing water  ¼ of world’s electricity  Opposition to dams ► Solar  Energy from sun  Thermal and photovoltaic  Wind generation  Air Pollution ► Human causation  Predominately fossil fuels ► Acid deposition  Acid rain - sulfur, nitrogen oxides ► Urban air pollution  Wind, temperature, sunlight Human Air Pollution Sources, US 2002  Acid deposition in North America  Water Pollution ► Source  Point  Non–point ► Concentration and dilution ► Reduced oxygen levels  Biochemical oxygen demand ► Wastewater and disease ► Chemical and toxic pollutants  Controlling Pollution ► Controlling pollution  Common strategy  Removal before entering environment ►Sewage treatment ►Catalytic converters ►Smoke stack scrubbers ► End of pipe strategies  Preventing Pollution ► Paradigm shift in the 1990’s  Stop producing pollution ► Factors  Mounting liability and regulation concerns  Reduce costs  Improve image with consumers and regulators  Forests ► Uses  Renewable natural resource  Timber, paper, wood products  Recreational ► Ecosystem  Habitat  Carbon production  Biodiversity  Forest Management ► Resolving user conflict ► Balancing resource and recreation ► Government involvement ► Marketplace demands End of Chapter 9