Fossil Fuels and Energy Consumption: Abundance, Patterns, and Alternatives - Prof. Jeffrey, Study notes of Forestry

Download Fossil Fuels and Energy Consumption: Abundance, Patterns, and Alternatives - Prof. Jeffrey and more Study notes Forestry in PDF only on Docsity! 1. Energy. Basics – how abundant are major fossil fuels in different regions, what are major consumption patterns in the US and the world? What are the various alternative energy options and what are the advantages and disadvantages of each (including nuclear)? Abundant fossil fuels in different regions: - proven recoverable oil reserves (world supply estimated to last 50 years)– Nigeria 3.0%, Libya 3.1%, USA 2.7%, Russia 6.0%, Venezuela6.8%, Iran 11.4%, Kuwait 8.4%, UAE 8.5%, Iraq 10.0%, Saudia Arabia 23.0% - proven in-place natural gas reserves (world supply estimated to last 60-125 years)– Africa 7.8%, Asia Pacific 7.7%, North America 4.2%, South and Central America 4.1%, Other/Europe 8.7%, Russia 26.7%, Middle East 40.8% - proven coal reserves (world supply estimated to last 200-1500 years)– Asia Pacific 30%, Africa and Middle East 6%, North America 26%, South and Central America 2%, Europe and Eurasia 36% US energy consumption patterns: U.S. has shifted in recent decades from coal to oil and gas. Also uses small alternative energy sources. Transportation consumes 26%, residential and commercial building use 37.6%, industry 32.6%. - gasoline for your automobile 47% - heating costs 27% - water heater 10% - refrigerator 3% Various alternative energy options: Biomass (wood, grass, corn, etc.) – using biomass has less consequences for climate change. Replacing ALL fossil fuels with biomass would require 1/3 of plant growth on earth. - Big push for biofuel (ethanol, biodiesel): alcohol based fuel produced from plant products. - There are two types of ethanol – corn-based ethanol (uses corn) and cellulosic ethanol (uses wood, grass). Solar Energy – the amount of solar energy that reaches earth’s surface annually is 10,000 times greater than all commercial energy used. It is renewable and free of cost, no delivery necessary. Solar energy is intermittent though, because the amount changes with cloud cover, time of day, and season. - Passive solar system – allows sunlight to pass into living space and provide heat - Active solar system – converts sun energy to heat or electricity. Solar panels: usually absorb sun light and convert to heat. Photovoltaic cells – absorb sun light and convert to electricity. Wind Energy – estimated 20 million MW of wind power could be tapped worldwide. Wind energy typically operates at 35% efficiency rate under field conditions. Fifty times nuclear generation. Wind farms are large concentrations of wind generators producing commercial electricity. The negative impacts of wind farms are the interrupt view in remote places; they destroy sense of isolation, and potentially kill birds and bats. Nuclear Power – has nuclear fission which is the releasing of energy by splitting large atoms into smaller atoms. Nuclear fusion is the releasing of energy by combining (fusing) smaller atoms into large ones. All of our nuclear power comes from fission. - Advantages: extremely powerful source of energy, no greenhouse gases produced, and no sulfur compounds, ozone, etc. - Problems: tailings left over after mining uranium are toxic. Famous accidents like Three Mile Island, Pennsylvania, or Chernobyl, Ukraine. Nuclear waste half lives measure as over ten thousand years. 6-30 years of supply is minable if production is increased. 2. Conservation genetics – why genetic diversity is so good. Homozygous, heterozygous, heterozygosity. Natural selection, basic genetics terms…alleles, mutation. Inbreeding, founder effect, bottleneck. Genetic diversity is necessary to maintain a healthy, viable population (Your savings account). Natural selection – differential survival and reproduction of a distinct genotype. Heterozygosity – proportion of individuals that are heterozygote for a locus. Allele – an alternate sequence of a gene Gene – is a segment of DNA that codes for a product. The Locus is the location of a gene. Genotype – is the genetic composition of an organism. Heterozygote (2 different genes) or homozygote (2 same genes). Phenotype – is the product of an organism’s genotype. Mutation – errors in the transmission of genetic information from parents to offspring. This is the ultimate source for new genes and alleles. Bottleneck – a reduction in population followed by an increase in population. Founder effect – a new population is established by a few individuals. 3. Conservation biology. Definition of biodiversity and reasons for saving it. Aesthetic intrinsic values. Taxol and teosinte as examples of products from biodiversity, economic values other than product value. Conservation biology: the study of threatened organisms and the process of extinction. 9. Restoration ecology, what is it, why important? Kissimmee River, FL. Problems with restoring ecosystems. Restoration ecology –it is the rebuilding of damaged habitats to a condition close to original. Why is it important? - because legislation requires it (mitigation laws) - Increased use of native plants in landscaping, along highways, etc. - Extreme level of habitat damage in many areas - In Indiana, 99% of tall grass prairie is gone, 95% of black oak savanna is gone. - Conservation of these areas requires restoration. Kissimmee River – first step to reduce flooding in past, army corps of engineers converted river to a channel. 75% of area wetlands were drained as a result. Their plan didn’t work because the area still floods. The bland eagle population dropped, and water flow declined. Much of the drained land was converted to pastures, so more waste came off the land into the marshes; also increased soil erosion. 10. Human population growth: age pyramids, current and predicted world population, demographic transition model, strategies for slowing population growth. Age pyramids – in many developing countries, huge percentages of the population is very young. Some developed nations have aging populations. Current populations – world=6.7 billion, U.S. =305 million, China=1.3 billion, India=1.2 billion Predicted world population by 2100 – best case scenario is 8 billion and worst case scenario is 13 billion. Most recent study in 2007 estimates 9.2 billion people on earth. Demographic transition model – has 4 stages of a population’s development: - Stage 1 – early history of society. High birth rates and high death rates, low population and low population growth. - Stage 2 – start of modernization, first change is decreased death rates due to better food, healthcare, etc. birth rates remain high (family choice). This causes high population growth. - Stage 3 – industrialization. Less needs for families, so lower birth rates because families choose to have fewer kids. Death rates also lower. High population size, and population sizes begins to decrease. - Stage 4 – stable populations. Low birth and death rates, but total population is high. Little to no population growth. Few countries have reached this stage. Strategies for slowing population growth: - Increase death rates – inhumane and unethical. - Decrease birth rates – “family planning” programs, increased education (especially for women), increased economic opportunities (especially for women. 11. Under nutrition, malnutrition, famine. Slash and burn agriculture – what is it and why is it bad at current population levels. Ways of increasing food supply. Green revolution. Under nutrition – diets with less than minimum daily caloric requirements. Varies with human population. Malnutrition – diets with less than minimum requirements of a nutrient (protein, vitamins, etc.) iron deficiency is the most common dietary imbalance in the world; it leads to anemia. Some good sources of iron are red meat, eggs, legumes, and green vegetables. Famine – characterized by large scale food shortages, massive starvation, social disruption, and economic chaos. Environmental conditions are immediate trigger, but politics and economics are often underlying problems. Aid from rich countries often distributes surplus commodities and produces feeling of generosity. Food camps have serious drawback: stress and crowding, lack of sanitation, close contact to epidemic diseases. Ways of increasing good supply: - Greater productivity. Better crops, better techniques, genetic engineering. - Climate change affects production of food. This may be caused by amounts of precipitation in areas. Ways to ensure your crops will grow: farmers can shift farm operations to areas with enough rain, use more irrigation, and develop drought resistant crops. Slash and burn agriculture – cultivate more land but the best land is already in use. Also, losing farmland in many areas. Plus need land for wildlife, human housing, etc. Green revolution – spread of new varieties around the world. 12. Genetic engineering: terms (transgenic, GMO, etc.) Gene splicing, cloning – know basics and differences between 2 techniques. Potential problems/benefits of each. Genetic engineering – changing the genetic makeup of an organism. Traditional breeding is a form of gene engineering but it is slow. GMOs (genetically modified organisms) – contain DNA possessing genes borrowed from unrelated species. Because of GMO, we can produce crops with pest resistance and wider tolerance levels. Opponents fear traits could spread to wild varieties, and increased expense would largely hurt small farmers. 60% of all processed food in North America contains transgenic products. Gene splicing – method of placing a gene from one organism into a different one, creating the desired trait in the second organism. Often used a bacteria or a virus as a vector. - Problems: crop species may hybridize with weedy species in same field to make a super weed. GM variety may escape, and outcompete the native species altogether. Gene cloning – removal of whole DNA of one organism, and replacing it with the DNA of another. The result is an exact copy of the original organism; “clones.” - Problems: not sure if cloned animals will have the same health and lifespan as normal animals, reduces, genetic variation, and will cloning animals lead to cloning humans?