environmental science docs

Chapters 6-8, 12

3 Prospectives: Family Planning: Developmental Distributivity: Crisis Environmentalist: Life Boat: You can only fit so many people on the lifeboat You can only let on so many people otherwise it will sink Laudato Si' Chapter 1: Against what we were learning in class: People who focus on the number of humans as the only problem are mistaken The inequality of quality of life is a more immediate problem Science and interconnectedness vs catholic theology Categorize the pope into the worksheet from the last class Equations You Need To Know: Doubling rate: 70/rate= #years it takes to double population Exponential growth: Nt=N0ert r= the natural rate of population change Chapter 6: Human Population Problems of overpopulation Demographic Transitions- understand graphs (how it changes in each phase) KNOW THIS! Pre-Industrial Stage Birth rates and death rates high Death rates high because disease is widespread due to lack of strong medical care and unreliable food Birth rates high to compensate for high infant mortality rate and lack of reliable birth control Children are valuable as workers Transitional Stage Declining death rates due to increased food production and improved medical care Birth rates still high because people have not gotten used to new economic and social conditions Industrial Stage Increases employment opportunities (esp. For women) Children less valuable in economic terms Birth rates fall which reduces population growth Post-industrial Stage Birth and death rates fall to low stable levels Solutions Figure out ways to reduce the fertility rate in developing nations Better education for women Better access to birth control/ condoms Socially have boys and girls equal. (Women will then not continue to have children until they have at least 1 boy) "Human K"= Carrying Capacity How many people we can fit on the earth Quality of Life Affluence: Standard of living/how many resources you have access to We cannot add people forever I=PAT Model Impact Population Affluence Technology Strategies to limit population growth What changes do you have to make to get down to 1 earth (adjust quality of life) Initiatives to give women skills to make a living Family Planning Access to condoms/Birth control China's one child policy---worked Focuses on incentives and punishments Preference of sons -- led to some abortion of girls Japan Not having enough people to support the elderly Low birth rates Case Study of women in Africa High population density, low economic stability/growth Exponential growth equation, doubling time equations* Chapter 7: Soil, Agriculture, and the Future of Food Soil degradation: Quality of soil Ability to hold water How well it is able to hold nutrients Genetic engineering- bacteria used to mutate animals ID a trait that you want to put into a crop, that trait may exist in a virus fungus or animal. Extract DNA from the animal, and implant it into bacteria and grow a lot of bacteria (grows quickly). Get plasma out of bacteria, take the DNA copies and put it into a plant that will be transformed Using pesticides can harm the ecosystem- the pests evolve resistance GMOs do not harm people's health We need soil to grow plants to provide nutrients and hold moisture for plants Know the problems and solutions Irrigation water Ways to minimize water use Solutions for: Reduce the loss of soil/erosion Shelterbelts- shields wind Crop rotation Intercropping Contour farming- perpendicular to slope Synthetic fertilizers Intercropping Conservation tillage Synthetic Pesticides Natural predators Intercropping Crops use a lot of water so use.. Terracing Drip irrigation Chapter 8: Biodiversity Sixth mass extinction Invasive species Overharvesting If everyone was vegetarian we could feed more people Chapter 12: Water Just Pollution and Fisheries! Sources of pollution and the influence of that pollution Oil spills Pesticides Nutrients pollution Soil from farms move down mississippi (nitrogen and phosphorus) and create the dead zone (lack of oxygen in the ocean) in the gulf of mexico Point source v. Nonpoint source Easier to control if it's a point source (one source of pollution) Fisheries Use them to supply food, instead of cattle, etc Overfishing* serious problem (so few fish now, and smaller) Freshwater Pollution

Chapter 13-16

Chapter 13: Atmospheric Science, Air Quality, and Pollution Control Case Study LA has the worst smog Sister Cities program Mexico City also has really bad smog Most of the pollution is generated by traffic Both LA and Mexico City are surrounded by mountains making it so thermal inversions can trap pollutants over the city Mexico City's high altitude makes solar radiation more intense which worses smog formed by the interaction of pollutants with sunlight Mexico City has taken many approaches to clean the air and it has made it much better The Atmosphere The Atmosphere: the layer of gases that envelops our planet Moderates our climate Provides oxygen Shields from emeteors Shields from solar radiation Transports and recycles water and nutrients Is made up of 78% nitrogen and 21% oxygen with the remaining 1% being argon and minute concentrations of other gases Humans are altering the quantities of gases like carbon dioxide, methane, and ozone Troposphere: the bottommost layer Air movement drives the planets whether Contains 3/4s of the atmosphere's mass Air gets colder with altitude Tropopause: where the temperatures stabilize and acts like a cap, limiting mixing between the troposphere and the stratosphere Stratosphere: 11-50 km above sea level Drier and less dense than the troposphere Gases have little vertical mixing so pollutants and substances that enter it stay for a long time Warms with altitude Its ozone and oxygen absorb the sun's uv radiation Ozone layer: where most of the atmosphere's ozone concentrates (this is an area in the stratosphere) It absorbs and scatters incoming uv radiation so it greatly reduces the amount of radiation that reaches the earth UV light is bad for living tissue Mesosphere: above the stratosphere Temperatures decrease with altitude Where incoming meteors burn up Thermosphere: above the mesosphere Exosphere: the region where the atmosphere merges into space The sun influences weather and climate 70% of solar energy is absorbed by the atmosphere and planetary surface while the rest is bounced back up into space Land and surface water absorb solar energy and then emit thermal infrared radiation which warms the air and causes some water to evaporate Air near near earth's surface tends to be warmer and moister than air at higher altitudes Convective circulation: Warm air, being less dense, rises and creates vertical currents As air rises into regions of lesser atmospheric pressure, it expands and cools, causing moisture to condense and fall as rain Once the air cools, it descends and becomes denser, replacing warm air that is rising The descending air picks up heat and moisture near ground level and prepares to rise again, continuing the process. This cycle influences both weather and climate Weather: specifies atmospheric conditions in a location over minutes, hours, days, or weeks Climate: describes typical patterns of atmospheric conditions in a location over years, decades, centuries, millennia Inversions affect air quality Normal temperature profile: air in the troposphere becomes cooler as altitude increases and because warm air rises, vertical mixing results Temperature inversion/thermal inversion: departure from the normal temperature profile A layer of cool air forming beneath a layer of warmer air Inversion layer: the band of air in which temperature rises with altitude Ex. common type of inversion is in mountain valleys where slopes block morning sunlight, keeping ground-level air within the valley shaded and cool Thermal inversions trap pollutants near the ground Outdoor air quality Air pollutants: gases and particulate material added to the atmosphere that can affect climate or harm people or other living things Air pollution: the release of air pollutants Outdoor air pollution/ambient air pollution Greenhouse gases is the biggest factor of air pollution Some air pollution can be caused naturally from: Fires Volcanic eruptions Windblown dust But sometimes we cause these Point source: describes a specific location from which large quantities of pollutants are discharged Ex. Coal-fired power plant Non-point source: are more diffuse, consisting of many small, widely spread sources Ex. Millions of automobiles Primary pollutants: pollutants released directly from a source Ex. Ash from volcanic eruption Secondary pollutants: when primary pollutants interact with other constituents of the atmosphere these form Residence time: the amount of time a pollutant spends in the atmosphere Pollutants with short residence time exert localized impacts over short time periods Pollutants that drive climate changed, and deplete the Earth's ozone have long residence time The Clean Air Act Created in 1963 Funds research into pollution control Sets standards for air quality, Imposes limits on emissions from new sources Enables citizens to sue parties violating the standards U.S. Environmental Protection Act (EPA) sets national standards for emissions and concentrations of major pollutants in ambient air States have to submit plans to EPA Six major pollutants that have to be monitored and reported to the EPA: Carbon monoxide (CO): colorless odorless gas produced primarily by the incomplete combustion of fuel Bad because it binds to hemoglobin in red blood cells, preventing the hemoglobin from binding with oxygen Vehicles and engines account for most CO emissions in the U.S. Sulfur dioxide (SO2): colorless gas with a pungent odor Most emissions results from the combustion of coal for electricity generation and for industry Once in the atmosphere it may react to form sulfur trioxide and sulfuric acid which may settle back to earth in acid deposition Nitrogen dioxides (NOx): a family of compounds that include nitric oxide (NO) and nitrogen dioxide (NO2) Most U.S. emissions results from when nitrogen and oxygen from the atmosphere react at high temperatures during combustion in vehicle engines also from fossil fuel combustion NOx emissions contribute to smog, acid deposition, and stratospheric ozone depletion Volatile organic compounds (VOCs): are carbon-containing chemicals emitted by vehicle engines and a wide variety of solvents, industrial processes, household chemicals, and consumer items VOCs can react to produce a number of secondary pollutants, as occurs in urban smog Particulate matter: composed of solid or liquid particles small enough to be suspended in the atmosphere Scientist classify particulate matter by the size of particles Lead (Pb): a heavy metal that enters the atmosphere as a particulate pollutant Lead containing compounds in gasoline Exhaust from combustion of leaded gas can make lead airborne which can be inhaled or go into land and water If it goes into the food chain it accumulates into the body tissues and can cause ventral nervous system problems and other ailment Air quality has improved In the U.S. EPA and the states monitor outdoor air quality by measuring concentrations of six criteria pollutants Criteria pollutants: pollutants judged to pose substantial risk to human health Carbon monoxide Sulfur dioxide Particulate matter Lead Nitrogen dioxide: a type of nitrogen oxide that is a foul-smelling, highly reactive reddish brown gas that contributes to smog and acid deposition Tropospheric ozone: a secondary pollutant created by the reaction of nitrogen oxides and volatile carbon-containing chemical in the presence of sunlight which is a major component of photochemical smog Air Quality Index (AQI): a value from 0-500 that reflects the pollutants (one of the 6 criteria pollutants) concentration and that is calculated by the EPA with the data it complies Below 100= satisfaction Above 100= unhealthy Air pollution is getting worse in industrializing nations Mexico City Causes problems in the cardiovascular and respiratory system Can also affect the brain Worse at low elevations India China Smog Smog: an unhealthy mixture of air pollutants that often forms over urban areas as a result of fossil fuel combustion Industrial smog: main components are sulfur dioxide, sulfuric acid, and soot When coal and oil is burned some portion is completely combusted forming CO2 Some is partially combusted producing CO Some remains unburned and is released as soot (particles of carbon) Coal contains mercury and sulfur and when sulfur reacts with oxygen it forms sulfur dioxide which can turn into sulfuric acid and other chemicals Still a problem in industrializing regions such as China, India, and eastern Europe Photochemical smog: forms when sunlight drives chemical reactions between primary pollutants and atmospheric compounds, producing a potent cocktail of over 100 different chemicals, tropospheric ozone often being the most abundant, contains NO2 so it is normally a brownish haze Hot, sunny and windless days in urban areas provide perfect conditions Exhaust from morning traffic releases NO and VOCs into the air and then sunlight promotes the production of ozone and other secondary pollutants, leading pollution to peak in the midafternoon Ozone Depletion Ozone in the stratosphere protects life on Earth by absorbing the sun's ultraviolet (UV) radiation, which can damage tissues and DNA Ozone-depleting substances: Halocarbons: human-made compounds derived from simple hydrocarbons in which hydrogen atoms are replaced by halogen atoms, such as chlorine, bromine, or fluorine Chlorofluorocarbons a type of halocarbon (CFCs stay in the stratosphere for a century or more) Ozone hole: a thinned ozone concentrations over Antarctica Ozone concentrations is roughly half the historic levels Always reappears in the spring During winter: Icy clouds form in the stratosphere containing condensed nitric acid which splits chlorine atoms of compounds such as CFCs The freed chlorine atoms accumulate in the clouds trapped over Antarctica by circular wind currents In the spring: Sun dissipates the clouds which releases the chlorine atoms which begins destroying the ozone Solar radiation also catalyzes chemical reactions, speeding up the ozone depletion as temperatures warm Montreal Protocol Made in 1987 In this treaty, the world's nations agreed to cut CFC production in half by 1988 This treaty halted the advance of ozone depletion and stopped the Antarctic ozone hole from growing worse Will take the ozone a long time to recover because of how long the substances stay in Because of its success in addressing ozone depletion, the Montreal Protocol is widely viewed as a model for international cooperation on other global problems, from biodiversity loss to persistent organic pollutants to climate change Addressing acid deposition Acid deposition: deposition of acidic or acid-forming pollutants from the atmosphere onto Earth's surface Acid rain: most commonly acid deposition takes place by precipitation Can also occur by fog, gases, or the deposition of dry particles Acid deposition is one type of atmospheric deposition Atmospheric deposition: refers broadly to the wet or dry deposition of a variety of pollutants, including mercury, nitrates, organochlorines, and others How it is made: Originates primarily with the emission of sulfur dioxide and nitrogen oxides, largely through fossil fuel combustion by automobiles, electric utilities and industrial facilities Once airborne, these pollutants react with water, oxygen, and oxidants to produce compounds of low pH, primarily sulfuric acid and nitric acid Suspended in the troposphere, these acids can travel days or weeks for hundreds of kilometers Acid deposition has many impacts Acids leach nutrients such as calcium, magnesium, and potassium ions from topsoil, harming plants and soil organisms Acid deposition also "mobilizes" toxic metal ions such as aluminum, zinc, mercury, and copper by chemically converting them from insoluble forms to soluble forms Elevated soil concentrations of metal ions damage root tissue of plants Populations of snails and other invertebrates typically decline reducing the food supply for birds Acidic water runs off from land affecting streams, rivers, and lakes Acid deposition leaches aluminum ions out of soil and rock and into the waterways These ions damage the gills of fish and disrupt their salt balance, water balance, breathing, and circulation Addressing acid deposition Acid Rain Program that was established under the Clean Air Act of 1990 Set up an emissions trading system for sulfur dioxide Cap-and-trade program was an economic incentive Required power plants to reduce nitrogen oxide emissions Indoor air quality Indoor air generally contains higher concentrations of pollutants than outdoor air Health impacts from indoor air pollutants are worse than from outdoor air pollutants Indoor air pollution has the biggest effect in the developing world because poverty forces people to burn things in their home with little ventilation Primary indoor air health risks are cigarette smoke and radon Radon is the second-leading cause of lung cancer in the developing world Radon is a radioactive gas resulting from the natural decay of uranium in soil, rock, or water which can seep up from the ground into buildings Volatile organic compounds (VOCs), airborne carbon-containing compounds released by plastics, oils, perfumes, paints, cleaning fluids, adhesives, pesticides, and tiny living organisms are all indoor air pollutants Chapter 14: Global Climate Change Case study Island in the Indian Ocean called Maldives is having problems with the sea level rising from climate change Officials are upset because they are suffering from the climate change but contribute to it the least Held an underwater cabinet meeting The alliance of Small Island States (AOSIS) Climate change Global climate change: describes an array of changes in aspects of Earth's climate, such as temperature, precipitation, and the frequency and intensity of storms Fossil fuel combustion and deforestation are largely responsible for climate changes Global warming: refers specifically to an increase in Earth's average surface temperature Global warming is only one aspect of global climate change, but warming does in turn drive other components of climate change 3 natural factors that exert the most influence on the climate: Sun Atmosphere Oceans Greenhouse gases warm the lower atmosphere Greenhouse gases: water vapor (H2O, ozone (O3), carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4), halocarbons (a diverse group of mostly human-made gases that includes chlorofluorocarbons (CFCs)) Atmospheric gases having 3 or more atoms in their molecules tend to absorb infrared radiation Greenhouse effect: after absorbing radiation emitted from the surface, greenhouse gases re-emit infrared radiation. Some of this re-emitted energy is lost to space, but most travels back downward, warming the lower atmosphere (the troposphere), and the surface Global warming potential: refers to the relative ability of one molecule of a given greenhouse gas to contribute to warming Most greenhouse gas emissions from human activity consist mostly of CO2 Greenhouse gas concentrations are rising fast Greenhouse gases are natural and necessary but we are increasing them too fast Too much CO2 concentrations because Most carbon is stored for long periods in the upper layers of the lithosphere Extracting fossil fuels and them burning them is taking carbon from underground deposits and putting it into our atmosphere We have removed trees which reduces the biosphere's ability to remove carbon from the atmosphere Methane concentrations are rising from Tapping into fossil fuel deposits Raising livestock that emit methane Disposing organic matter in landfills Growing certain crops such as rice Nitrous oxide concentrations are elevated from Feedlots Chemical manufacturing plants Auto emissions Synthetic nitrogen fertilizers Other factors warm or cool the surface Aerosols: microscopic droplets and particles can either have a warming or cooling effect Soot particles or "black carbon aerosols": generally cause warming by absorbing solar energy Most aerosols cool the atmosphere by reflecting the sun's rays Radiative forcing: the amount of change in thermal energy that the factor causes (how scientists measure the degree of impact that a given factor exerts on Earth's temperature) Positive forcing warms the surface Negative forcing cools the surface Climate varies naturally for several reasons Solar output Ocean absorption As ocean water warms, it absorbs less CO2 because gases are less soluble in warmer water (a positive feedback effect that accelerates warming of the atmosphere) Ocean circulation Milankovitch cycles Describe three types of periodic changes in earth's rotation and orbit around the sun Alter the way solar radiation is distributed over earth's surface By modifying patterns of atmospheric heating, these cycles trigger long-term climate variation Proxy indications tell us of the past Proxy indicators: are types of indirect evidence that serve as proxies, or substitutes for direct measurement Ex. Ice caps, tree rings, coral reefs Models help us predict the future Climate models: programs that combine what is known about atmospheric circulation, ocean circulation, atmosphere-ocean interactions, and feedback cycles to simulate climate processes Used to understand how climate systems function and predict future climate change Test with the past to see if correct Scientific evidence for climate change is extensive Intergovernmental Panel on Climate Change (IPCC) Reviews and summarizes the knowledge on climate change Fifth Assessment report Released in 2013 and 2014 by IPCC Reports observed trends Predicts future changes Discusses impacts of climate disruption Discusses strategies we might pursue in response Current and future trends and impacts Temperatures continue to rise Precipitation is changing Warmer atmosphere speeds evaporation and holds more water vapor Some regions are having more precipitation while others are not Extreme weather is becoming "the new normal" No particular weather event can be directly attributed to climate change Because warming has been greatest in the Arctic, this has weakened the intensity of the Northern Hemisphere's polar jet stream Northern Hemisphere's polar jet stream: a high-altitude air current that blows west-to-east and meanders north and south, influencing the weather across North America and Eurasia These long lazy loops move west to east more slowly, and may get stuck in north-south orientation for long periods of time. Meteorologists call this an atmospheric blocking pattern because it blocks the eastward movement of weather systems Melting ice has far-reaching effects In a process of positive feedback, warming causes more ice and snow to melt, which in turn causes more absorption of radiation and more warming Warming temperatures are causes permafrost to thaw that can release methane which acts as a positive feedback mechanisms that intensifies climate change Rising sea levels may affect hundreds of millions of people Sea levels are rising from the melting glaciers and because ocean water is warming which makes it expand Rising sea levels can lead to beach erosion, coastal flooding, and intrusion of saltwater into aquifers Storm surge: a temporary and localized rise in sea level generated by a storm Acidifying oceans imperil marine life Ocean acidification: as carbon dioxide concentrations in the atmosphere rise, the oceans absorb more CO2 altering the ocean chemistry, making seawater more acidic Threatens marine life As seawater becomes more acidic, carbonate ions become less available, and calcium carbonate begins to dissolve which is what a lot of marine animals need to survive Climate change affects organisms and ecosystems Climate change affects society Agriculture Forestry Health Economics Impacts vary by region Temperature changes have been greatest in the Arctic Responding to climate change Can respond in two fundamental ways (need to do both): Mitigation: alleviate or reduce the severity of the problem Pursue actions that reduce greenhouse gas emissions to lessen the severity of climate change Adaption: goal is to adapt to change Strategies to cushion ourselves from the impacts of climate change Developing solutions in electricity generation and transportation Electricity generation Fossil fuel combustion generates ⅔ of U.S. electricity and coal accounts for the most of the resulting emissions Need to lower this Use natural gases Energy-efficient products Power producers can capture excess heat from electricity generation and use it Carbon capture: refers to technologies or approaches that remove carbon dioxide from emissions Carbon storage/carbon sequestration: in which carbon is stored, under pressure in deep salt mines, depleted oil and gas deposits, or other underground reservoirs Transportation Currently inefficient need to change this Change technology to make more fuel-efficient Electric and gasoline-electric hybrid vehicles, hydrogen fuel cells, and alternative fuels such as compressed natural gas and biodiesel Currently, the EPA is responsible for addressing emissions U.N. Framework Convention on Climate Change: outlined a plan to reduce greenhouse gas emissions to 1990 levels by the year 2000 through voluntary approach Kyoto Protocol: mandated signatory nations, by the period 2008-2012, to reduce emissions of six greenhouse gases to levels below those of 1990 2 arguments about this U.S. objected to how it required industrialized nations to reduce emissions but did not require the same of rapidly industrializing nations such as China and India This was countered with that industrialized nations created the current problem and therefore should take the lead in resolving it Emissions trading programs: seek to harness the economic efficiency of market capitalism to control pollution by allowing business, industry, or utilities flexibility in how they do so Carbon offsets: voluntary payments intended to enable another entity to help reduce the emissions that one is unable to reduce (payment offset's one's emissions) Cons: need a lot of oversight to make sure the payments are being correctly used Cap-and trade system: industries and utilities would compete to reduce emissions for financial gain (self-sustaining) Cons: not effective enough, don't work quickly enough, and leave too much to chance Carbon tax: governments charge polluters a fee for each unit of greenhouse gases they emit Gives polluters a financial incentive to reduce emissions Cons: polluters pass the cost along to consumers by charging higher prices for their products or services Fee-and-dividend: funds from the carbon tax, or "fee", are transferred as a tax refund, or "dividend" given to taxpayers In theory, this system should provide polluters a financial incentive to reduce emissions while imposing no financial burden on taxpayers and no drag on the economy This approach is a type of revenue-neutral carbon tax because there is no net transfer of revenue from taxpayers to the government This approach is gaining broad political appeal Geoengineering Suck carbon dioxide out of the air Enhance photosynthesis by planting trees or fertilizing ocean phytoplankton Design "artificial trees": structures that chemically filter CO2 from the air Block the sunlight before it reaches earth Change our individual carbon footprint Carbon footprint: the amount of carbon we are responsible for emitting Chapter 15: Nonrenewable Energy Sources, Their Impacts, and Energy Conservation Case study Cabot Oil and Gas Corporation went to Dimock in Pennsylvania to drill for natural gas They would pay residents for their land to drill there Way more cons then the residents anticipated Shale gas: natural gas that is locked up in tiny bubbles dispersed throughout the shale rock Hydraulic fracturing/hydrofracking/fracking: Drilling deep into the earth and then angling the drill horizontally once it meets a shale formation Electric charge sets off targeted explosions that perforate the drilling pipe and create fractures in the shale Drillers then pump a slurry of water, sand, and chemicals down the pipe under great pressure The sand lodges in the fractures and holds them open while some of the liquids return to the surface Natural gas trapped in the shale migrates into the fractures and rises to the surface through the drilling pipe Pros of hydrofracking: employs people, keeps gases prices low, and increased use of natural gas reducing reliance on coal for electricity Exempted from seven major federal environmental laws so companies don't have to report what chemicals they are using or treat for chemical compounds in the wastewater Cons: contaminated drinking water, air pollution, uses huge amounts of freshwater, radioactive wastewater Fossil fuels We rely mostly on fossil fuels Fossil fuels: highly combustible substances formed underground over millions of years from the buried remains of ancient organisms We use 3 main fossil fuels in the form of a solid (coal), liquid (oil), and gas (natural gas) Nonrenewable Energy calculations Net energy: expresses the difference between energy returned and energy invested Net energy= energy returned - energy invested Energy returned on investment (EROI ratios) EROI= energy returned / energy invested Higher EROI ratios means that we receive more energy from each unit of energy that we invest Fossil fuels: their formation, extraction and use Coal: a hard blackish substance formed from organic matter (generally woody plant material) compressed under very high pressure, creating dense, solid carbon structures World's most abundant fossil fuel Typically results when water is squeezed out of such material as pressure and heat increase over time, and when little decomposition takes place Extraction Strip mining: machinery scrapes away huge amounts of earth Subsurface mining: digging vertical shafts and blasting out networks of horizontal tunnels to follow seams, or layer, of coal Mountaintop removal: blasting away entire mountaintops Used largely to generate electricity Clean coal technologies aim to reduce air pollution from coal Clean coal technologies: refer to techniques, equipment, and approaches that aim to remove chemical contaminants during the generation of electricity from coal at power plants Scrubbers: devices that chemically convert or physically remove pollutants Dry coal that has high water content to make it burn cleaner Gasification: coal is converted into a cleaner synthesis gas, or syngas, by reacting it with oxygen and steam at a high temperature giving us more power and less pollution Carbon capture and carbon storage Oil: contains a mix of various hydrocarbon molecules Formed from organic material (plankton) that was buried in the sediments on the ocean floor Extracted by drilling (once deposit is tapped the pressure is released and it rises and the remainder is pumped out) Used to fuel vehicles To estimate how long the remaining oil will last use the reserves-to-production ratio or R/P ratio: by dividing the amount of remaining reserves by the annual rate or production (extraction and processing) Peak oil: production of oil will peak and decline (tends to decline once reserves are depleted halfway) Hubbert's peak Natural gas: a gas consisting of methane (CH4), and lesser, variable amounts of other volatile hydrocarbons Formed from organic material (plankton) that was buried in the sediments on the ocean floor Two process give rise to natural gas: Biogenic: anaerobic decomposition of organic matter by bacteria Thermogenic gas: results from compression and heat deep underground Extracted by drilling (once deposit is tapped the pressure is released and it rises and the remainder is pumped out) Used to generate electricity Emits half as much carbon dioxide per unit of energy produced as coal and ⅔ as much oil Some look to it as a "bridge fuel" Cons: extraction causes water pollutions and can leak methane to the atmosphere Petroleum: used to refer to oil and natural gas collectively Primary extraction: the initial drilling and pumping of oil or gas Secondary extraction: because ⅔ of a deposit remains after primary extraction some companies return and use new technology or approaches to force the remaining oil or gas out by pressure More expensive Directional drilling: helps to lessen some of the impacts of drilling by allowing drillers to bore down vertically and then curve to drill horizontally Unconventional fossil fuels (not yet being used widely) Oil sands/tar sands: contains heavy form of petroleum Emit way more greenhouse gases than the ones above Uses a ton of water, devastates landscapes, and pollutes waterways Oil shale: sedimentary rock filled with organic matter that can be processed to produce a liquid form of petroleum called shale oil Methane hydrate/ methane clathrate/methane ice: an ice-like solid consisting of molecules of methane embedded in a crystal lattice of water molecules Cons: difficult and expensive to extract and process Net energy values and EROI ratios are very low Economics determines how much will be extracted Proven recoverable reserve: the amount of fossil fuel that is technologically and economically feasible to remove under current conditions Increase as extraction technology improves or as market prices of the fuel rise Decrease as fuel deposits are depleted or as market prices fall Energy efficiency and conservation Energy efficiency: describes the ability to obtain a given amount of output while using less energy input\ Is a primary means of conservation Results from technological improvements Energy conservation: describes the practice of reducing wasteful or unnecessary energy use Results from behavioral choices Cogeneration: excess heat produced during electricity generation in power plants is captured and used to heat nearby workplaces and homes and to produce other kinds of power Rebound effect: gains in efficiency from better technology may be partly offset if people engage in more energy-consuming behavior as a result Nuclear power Nuclear energy: is the energy that holds together protons and neutrons in the nucleus of an atom Nuclear reactors: facilities contained within nuclear power plants that converts nuclear energy into thermal energy Nuclear fission: is the reaction (the splitting apart of atomic nuclei) that drives the release of the nuclear energy inside nuclear reactors This reaction can be used in a nuclear bomb, but if controlled in the reactors its fine Comes from processed and enriched uranium Uranium is obtained by mining and contains minerals that are uncommon and in finite supply so it's a nonrenewable energy Pros: doesn't produce air pollution, less needs to be mined than coal Cons: arranging for safe disposal of radioactive waste, accidents could be really bad Three Mile Island Radiation leak- could have been really bad but it was all in the building Chernobyl- most severe nuclear accident yet, explosion that lead to radiation getting everywhere (huge increase in cancer rates) Fukushima- earthquake and tsunami caused plants to explode and leak radiation Chapter 16: Renewable Energy Alternatives Case study Germany goes solar Top users of PV solar technology, 2nd in biomass, 3rd in solar water heating, and 1st in biodiesel production Feed-in tariff: a system whereby utilities are required to buy power from anyone who can generate power from renewable energy sources and feed it into the electric grid Applies to all forms of renewable energy Renewable energy sources Advantages: reduces air pollution and greenhouse gas emissions that drive global climate change, reduces reliance on imported fuels, can help generate income and property tax for rural areas, help people in developing regions of the world produce their -own energy, and helps produce jobs (green-collar jobs) Solar energy How to harness it: Passive solar energy collection: buildings are designed to maximize absorption of sunlight in winter yet to keep the interior cool in the summer, techniques also use materials that absorb heat, store it, and release it later (simples way) Active solar energy collection: makes use of devices to focus, move, or store solar energy (flat plate) Concentrated solar power (CSP) plants: gather sunlight form a large area and focuses it to a small area (transfers electricity via the electric grid) Problem: needs lots of land and disrupts the land Photovoltaic (PV) cells: convert sunlight to electrical energy when light strikes one of a pair of plants made primarily of silicon, a semiconductor that conducts electricity (can connect to a battery to store the charge until needed) Net metering: the value of power the customer provides is subtracted from the consumer's monthly bill Benefits: No emissions Endless supply Local control over power Creates jobs Technologies are quiet, safe, use no fuel, and require little maintenance Drawbacks: Location Timing Very expensive Wind power How to harness it: Wind turbines: mechanical assemblies that convert wind's kinetic energy into electrical energy Benefits: No emissions Good EROI ratio Can be used on many different scales (large and small) Creates jobs Drawbacks: No control over when it will occur Varies from time to time and place to place Hazard to birds and bats People don't like the looks of them Geothermal energy How to harness it: Directly from geysers at the surface By drilling down to the heated groundwater which can be used directly for heating buildings Geothermal power plants harness naturally heated water and steam to generate electricity Ground-source heat pumps (GSHPs): pumps that provide heating in the winter by transferring heat from the ground into buildings and provide cooling in the summer by transferring heat from buildings into the ground Benefits: Does not produce emissions Does not affect the amount of thermal energy produced underground Drawbacks: If the plant uses up water before it is recharged it will run out of water Some groundwater is laced with salts and minerals that can corrode equipment and pollute the air Restricted to regions where we can tap energy from naturally heated groundwater (trying to avoid this by enhanced geothermal systems) Ocean energy sources How to harness it: Harness tidal energy by making dams across the outlets of the tidal basins (as tidal currents pass through the dam, water turns turbines to generate electricity) Wave energy (not as successful) Ocean currents Ocean thermal energy conversion relies on the ocean's sun-warmed surface being warmer than the deep water Benefits: Does not produce emissions Infinite source Drawbacks: Technologies not fully developed Expensive Hydroelectric power (2nd most used source) How to harness it: Use kinetic energy of flowing river water to turn turbines and generate electricity Storage technique: storing the water of a river behind the dam and then letting it go through Run-of-river technique: divert a proportion of the river's flow making it pass through a power house (not good for all year long but it is less disruptive to the river) Pumped storage: water is pumped from a lower reservoir to a higher reservoir at times when demand for power is weak and prices are low. When demand is strong and prices are high, water is sent downhill through a turbine, generating electricity (good for controlling the timing of the flow and good to pair with another energy source to help with natural dips) Benefits: Renewable Efficient (Really high EROI ratio) No carbon dioxide or other pollutants are emitted Drawbacks: Damming rivers destroys habitat Natural flooding cycles are disrupted trapping sediments Thermal pollution Block the passage of fish or aquatic animals Bioenergy/Biomass energy How to harness it: Burning biomass for heating Fuelwood (firewood) Use biomass to generate electricity Waste products Frops Combustion strategies Using manure Burning waste to heat water and create steam to turn generators and turbines Gasification Pyrolysis Biofuels can power vehicles Ethanol Biodiesel Novel Biofuels Algae can provide a source of carbon capture, can grow fast, and can grow a lot of places Benefits: Putting our waste to use Reduces carbon emissions Capturing landfill gas reduces emissions of methane Reduces emissions of sulfur dioxide Drawbacks: Loose natural ways to restore soil fertility Growing the crops used for diesel and ethanol exert heavy impacts on the land Not carbon-neutral if forests are destroyed to plant bioenergy crops Hydrogen and fuel cells (not a thing yet) How to harness it: Hydrogen is an energy carrier so it could could energy that could be used for later times Electrolysis: produces pure hydrogen (which isn't just found) Benefits: Will never run out of it Water and heat are the only waste products from a hydrogen fuel cell Energy efficient Drawbacks: Depends on the source of electricity used for electrolysis Depends on how hydrogen is extracted Lack of infrastructure

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Chapter 1: Science and Sustainability" An Intro to Environmental Science Q1. Agricultural Revolution → transition to agricultural way of life, producing more food to meet nutritional needs, which led to population growth and individuals having more children. Industrial Revolution → advances in technology, sanitation, and medicine and enhanced food production. People are able to gain better medical care and more access to food, causing them to live longer and have more children (baby boomers). Some negatives include overpopulation, stress on natural systems, availability of resources, and pollution Q2. Ecological Footprint → total area of Earth's productive biological surface that a given person or population "uses" once all direct and indirect impacts are totaled up. Overshoot → excess use of renewable resources. We are overshooting Earth's capacity to sustainably support us (50% more resources are being used than are available) Q3. Scientific Method: Observation → Question → hypothesis → Predictions → test → results Peer review is an essential part of the scientific method, as it helps to prevent faulty research and offer a fresh pair of eyes Q4. Environmental science is the study of Earth's natural systems, how they function, how they affect people, and how we influence them. It is interdisciplinary, pulling from natural sciences, social sciences, environmental studies. Q5. Anthropocentrism → human centered view of our relations with the environment Evaluates based solely on the impacts on people Biocentrism → gives value to living things/ the biotic realm in general Human and nonhuman life have ethical standing Ecocentrism → judges actions in terms of effects on whole ecological systems, living and nonliving things and the relationships among them Q6. Preservation Ethic vs. Conservation Ethic Preservation ethic → developed by John Muir, holds that we should protect the natural environment in a pristine, unaltered state. Says nature deserves protection for its own sake, and that nature promotes human happiness Conservation ethic → founded by Gifford Pinchot, more anthropocentric view, saying that people should put natural resources to use but we have a responsibility to manage them wisely. Utilitarian standard, saying we should allocate resources so as to provide the greatest good to the greatest number of people for the longest time Q7. Aldo Leopold's lands ethic → he argued that people should view themselves and the land as members of of the same community and that we are obligated to treat the land in an ethical manner. He describes a community of interdependent parts to which an individual belongs, and individuals are obligated to respect one another and the community/land. The community includes soil, water, plants, and animals. Q8. Environmental justice → involves the fair and equitable treatment of all people with respect to the environmental policy and practice, regardless of their income, race, or ethnicity. Argues that poor people tend to be exposed to a greater deal of pollution, hazards, and environmental degradation than are richer people, and that minorities tend to suffer more than their share of exposure to most hazards. Q9. Sustainability means living within our planet's means, such that Earth can sustain us - and all life - for the future. Some sustainable solutions include: Renewable energy sources (solar, wind, geothermal) Soil conservation and organic agriculture Reducing air pollution in wealthier nations Protecting habitats and safeguarding endangered species Pretty much anything else we talked about this semester Chapter 2: Environmental Systems: Matter, Energy, and Ecosystems fative feedback loop is more common to nature. An example of positive feedback loop could be global warming. An example of a negative feedback loop could be hormonal regulation (sweating/ shivering). Q2. Hypoxic conditions can develop in coastal marine ecosystems such as the northern Gulf of Mexico because runoff from fertilizers in crops and sewage spill into rivers which flow into larger bodies of water such as the Gulf of Mexico. Q3. An ion is an electrically charged atom(s) whereas an isotope is an atom with differing numbers of neutrons. Q4. The two major forms of energy are Potential energy and Kinetic energy. An example of potential energy and kinetic energy could be river water behind a dam. It builds energy until it is released and becomes kinetic energy. The first law of thermodynamics states that energy can change from one form to another but cannot be created or lost. The total energy in the universe remains constant and is said to be conserved. The second law of thermodynamics states that the nature of energy tends to change from a more-ordered state to a less-ordered state; that is, entropy forest. Q5. Photosynthesis uses solar energy to initiate a series of light reactions. In these reactions , water molecules split and react to form hydrogen ions and molecular oxygen, thus creating the air we breathe. Cells use cellular respiration to convert glucose back into water and carbon dioxide. Q6. Light energy from the sun drives photosynthesis in producers, which begins the transfer of chemical energy among other organisms and nonliving organic matter. Energy exits the system through respiration in the form of heat. Q7. 5 different ecosystems services Provide fish, game, crops, nuts, and fruits that we eat Supply lumber, fuel, metals, fodderm and fiber Regulates oxygen, carbon dioxide, stratospheric ozone and other atmospheric gases Regulates temperature and precipitation by means of ocean currents, cloud formation, and so on. Control crop pests with predators and parasites Q8. Role in the carbon cycle: Cars- greatly increases the flux of carbon from the lithosphere to the atmosphere and has shortened the residence time of carbon in fossil fuel deposits. Photosynthesis- releases carbon back into the atmosphere and waters as CO2 The oceans- they absorb carbon-containing compounds from the atmosphere, terrestrial runoff, undersea volcanoes, and the detritus of marine organisms. Earth's crust- Carbon trapped in sedimentary rock may reside there from hundreds of millions of years but they could be released. Q9. Nitrogen fixing bacteria-term describing bacteria that live in a mutualistic relationship with many types of plants and provide nutrients to the plants by converting nitrogen to a usable form. Denitrifying bacteria-bacteria that convert the nitrates in soil or water to gaseous nitrogen and release it back into the atmosphere. Q10. We affect the carbon cycle by burning fossil fuels and burning trees. We affect the phosphorus cycle by mining. We affect the nitrogen cycle by fertilizers & burning forests & fossil fuels. We affect the hydrologic cycle by fertilizers, pesticides and damming rivers. Chapter 3: Evolution, Biodiversity, and Population Ecology Q1. Define the concept of natural selection in your own words, and explain how it follows logically from a few common observations of nature. Natural selection is the survival of the animals that have inherited traits through adaptation that allow them to survive and pass along the trait. Q2. Describe an example of evidence for natural selection and an example for artificial selection. The honeycreeper is an example of natural selection. Some of the birds by chance had genes that gave them a natural resistance to malaria. These were the birds that survived and reproduced after malaria killed off many members of their population. Dog breeds are a result of artificial selection. Through selective breeding, dog breeders choose desirable traits. We have also created corn with bigger, sweeter kernels by using selective breeding. Q3. Describe the steps involved in allopatric speciation. This is when species form populations that become physically separated over some geographical distance. Once the species is separated, say a mutation arises in the DNA of an organism in one of the populations, this mutation can now only be spread through the population it is present in. Over time, each population will accumulate its own set of mutations. Eventually, the populations may diverge into different species and they will no longer be able to mate to produce viable offspring. Q4. Name two organisms that have become extinct or are threatened with extinction. For each, give a probable reason for its decline. Introduction of a foreign species can lead to another's extinction. For example, the Hawaiian petrel, a seabird that nests in the ground, is endangered as a result of predation by the Indian mongoose being introduced. The best known mass extinction brought about the end to the dinosaurs. Evidence suggests that the collision of a gigantic asteroid with the Earth caused this event. Q5. Define the terms species, population, and community. How does species differ from a population? How does a population differ from a community? Species- a particular type of organism. More precisely it is a population whose members can freely breed with each other to produce fertile offspring Population- a group of individuals of a given species that live in a particular region at a particular time Community- consists of an assemblage of interacting populations that inhabit the same area Q6. Define and contrast the concepts of habitat and niche. A habitat is the specific environment in which an organism lives. This consists of the living and nonliving elements around it. An organism's niche is its functional role in a community. It reflects its use of habitat and resources, its consumption of certain foods, its role in the flow of energy matter, and its interactions with other organisms. Q7. List and describe each of the five major population characteristics discussed. Briefly explain how each shapes population dynamics. Population size- the size of the population may increase, decrease, under go cyclical change, or remain stable Population density- high population density makes it easier for organisms to group together and find mates, but can also lead to competition and conflict if space, food, or mates are limited; close contact can also lead to spread of disease Population distribution- can either be random, uniform, or clumped Sex ratio- in a monogamous species, a 1:1 sex ratio maximizes population growth, most species are not monogamous so sex ratios vary Age structure- by combining this with other data on reproductive potential a population ecologist can predict whether the population will grow or shrink Q8. Can a species undergo exponential growth forever? Explain your answer. Exponential growth rarely lasts long. Every population eventually is constrained by limiting factors- physical, chemical, and biological attributes that restrain population growth. These factors determine the carrying capacity. Q9. Describe how limiting factors affect carrying capacity. Limiting factors-physical, chemical, and biological attributes that restrain population growth. Q10. What are some advantages of ecotourism for a state like Hawaii? Can you think of any potential disadvantages? (sorry for this crap answer) It helps these communities be able to afford to keep national parks and things like this. With tourism there can be negatives though, because they are getting more traffic which could cause them to want to build a road or something that goes through the park. Chapter 4: Species Interactions and Community Ecology Q1. Competition promotes resource partitioning. Competition occurs when organisms seek the same limited resources. Sometimes, one species is a very effective competitor and this excludes one species from using that resource entirely. But other times these species can coexist because they adapt as natural selection favors individuals that use slightly different resources or use the same resources in different ways. This is resource partitioning because the species divide the resources they use in common by specializing in different ways. For example, natural selection may drive one species of bird to specialize on larger seeds and the other to specialize on smaller seeds. Q2. Three main types of exploitative species interactions: Predation → the process by which an individual of one species (the predator) hunts, captures, kills, and consumes individuals of another species (the prey) Structures the food webs and help shape community composition Can drive population dynamics → increase in prey = more food for predators who will survive and reproduce Parasitism→ relationship in which one organism, the parasite, depends on another, the host, for nourishment or some other benefit while harming the host. Many parasites live inside their hosts, and do not cause their host immediate death as we see in predation. Parasites and hosts evolve in response to one another, and constantly adapt Herbivory → animals feed on the tissues of plants; most common→ insects that feed on plants Generally does not kill the plant but may affect its growth and reproduction Q3. Ways mutualism (relationship in which two or more species benefit from interacting with one another) affects our daily lives → our digestive tract is filled with microbes that help us digest food and carry out bodily functions, in return we provide them a place to live. Symbiotic mutualism → physically close mutualistic relationship→ an example of this is terrestrial plant species and fungi (mycorrhizae), where the plant provides energy and protection to the fungus while the fungus helps the plant absorb nutrients from the soil. Non-symbiotic mutualism → an example of this is pollination, where bees, birds, bats, etc. transfer pollen from flower to flower. Q4. At each trophic level, organisms use energy in cell respiration, and most ends up being given off as heat. Each trophic level only contains about 10% of the energy of the trophic level below it. This explains why eating at lower trophic levels (being vegan or vegetarian) decreases a person's ecological footprint. Each amount of meat or other animal product we eat requires the input of a considerably greater amount of plant material. So when we eat animal products, we use up far more energy per calorie that we gain than when we eat plant products. Q5. Food chain vs. Food web Food chain is a linear series of feeding relationships Food web is a more accurate representation of the feeding relationships in a community, because it is a visual map of energy flow that shows the many paths along which energy passes as organisms consume one another. Q6. A keystone species is a species that has a strong or wide-reaching impact far out of proportion to its abundance. It holds the structure together, and if it goes extinct, the rest collapses. Often, secondary or tertiary consumers near the tops of food chains are considered keystone species (examples include wolves, sea stars, sharks, sea otters) Q7. Primary v. Secondary Succession → if a disturbance is severe enough to eliminate all or most of the species in a community, the affected site may undergo a predictable series of changes called succession Primary succession → follows a disturbance so severe that no vegetation or soil life remains from the community that had occupied the site. A community is built from scratch. (Example: glaciers retreat, lakes dry up, or volcanic lava or ash covers a landscape) Secondary succession → begins when a disturbance dramatically alters an existing community but does not destroy all life and organic matter. Vestiges of the previous community remain and these building blocks help shape the process. (example. fire , storm, logging, or farming removes much of the biotic community) Q8. Restoration ecology → researching the historical conditions of ecological communities as they existed before our industrialized civilization altered them, and then devising ways to restore altered areas to an earlier condition. It is very important because the population continues to grow and development continues to spread, and it helps reestablish the land and ecosystem services that were once there. Q9. Because biomes are largely a function of climate, global climate patterns cause biomes to occur in large patches in different parts of the world. More specifically, which biome covers each portion of the planet depends on a variety of abiotic factors, including temperature, precipitation, soil conditions, and the circulation patterns of wind in the atmosphere and water in the oceans. Temperature and precipitation have the greatest influence. Aquatic systems, however are not shaped by air temp and precipitation, but by water temp., salinity, dissolved nutrients, wave action, currents, depth, light levels, and type of substrate, and are more clearly delineated by their animal life than their plant life. Chapter 5: Economics, Policy, and Sustainable Development Q1.Name and describe two key contributions that the natural environment makes to our economies. Natural resources are a major contribution from our environment. These include freshwater, trees, energy from sun, wind, water, and fossil fuels just to name a few. Our environment also has systems which purify air water, form soil, cycle nutrients, regulate climate, pollinate plants, and recycle wastes. These are all things our economies rely on heavily to function. Q2. Describe four ways in which neoclassical economic approaches can contribute to environmental problems. Neoclassical economics examines consumer choices and explains market prices in terms of our preferences for units of particular commodities. This bases everything off of finding the cheapest economic cost and ignoring ecological costs. Q3. Compare and contrast the views of neoclassical economists, environmental economists, ecological economists, particularly regarding the issue of economic growth. Neoclassical economics assumes that economic growth is essential for maintaining social order, because a growing economy can alleviate the discontent of the poor by creating jobs. Environmental economics feel we can modify neoclassical economic principles to make resources use more efficient and thereby attain sustainability within our current economic system. Ecological economists feel that sustainability requires more far-reaching changes. They believe society cannot surpass environmental limits. Q4. What are ecosystem services? Give several examples. Describe how economists have tried to assign monetary values to ecosystem services. Ecosystems provide us with life supporting services such as arable soil, waste treatment, clean water, and clean air. They have non-market values. Q5. Describe at least one major goal of and justification for environmental policy. Now articulate three problems that environmental policy commonly seeks to address. Q6. Chapter 6: Human Population Q1. Approximate global human population → 7.4 billion people. This number grows by 85 million each year Q2. Population continues to grow despite limitations because humans are a successful species and have continuously overcome those predicted limits on growth by developing new technologies and ways of securing new resources. Some of these technologies include better sanitation, better medical care, and increased agricultural output. Q3. Contrast views of environmental scientists with those of economists regarding whether population growth is a problem. Name several reasons why it is a problem. A book published by economist Thomas Malthus in 1798 stated that if society did not reduce the birth rate, that the death rate would reduce the population through war, disease and starvation. Agricultural improvements proved his theory wrong. This does not necessarily mean that human innovation will always find a way to support our population. To answer if continued population growth is a problem, we must ask whether we could maintain the quality of life we desire even if resource substitution could hypothetically enable our population growth indefinitely. Q4. IPAT Model → model that represents how our total impact on the environment results from interaction among population, affluence, and technology. Technology can increase environmental impact → technology that enhances our abilities to exploit minerals, fossil fuels, forests, or fisheries generally increases impact Technology can decrease environmental impact → technology that helps us reduce smokestack emissions, harness renewable energy, or improve manufacturing efficiency. Q5: Different Impacts on the Environment Population size, density, and distribution → global population of more than 7.1 billion is spread among more than 200 nations, and China has 1.36 billion and India has 1.28 billion, meaning that population is widely unevenly distributed among these 200 nations Uneven distribution means that certain areas have more environmental impact than others Areas with low population density are sensitive (S) and more vulnerable to impact, while others in high population areas receive a lot of human impact Age structure → populations are aging in many nations including the US This shift can challenge the economies, health care systems, families, and military forces due to fewer working age people being available to support social programs to assist the rising number of old people. Sex ratios → uneven ratios of men and women can be problematic → more competition among men for the few females, females being kidnapped and sold to men, increased HIV. like we saw in the India video where the women are forced to have children, but they do not want them to have females. Women are forced into having multiple children so that they can have a boy. Q6. The TFR is the average number of children born per woman during her lifetime. The replacement fertility is the TFR that keeps the population stable, and in the US it is approximately 2.1 (two children replace the mother and father, extra 0.1 accounts for the risk of a child dying before reaching reproductive age. In Europe, their TFR has dropped from 2.6 to 1.6 in the past half-century, and populations are declining in 18 of 45 European nations, and their rate of natural increase was between 0% and .1%. Q7. Fertility rates have fallen in many countries because of demographic transition. These nations have industrialized and industrialization decreases mortality and then lessens the need for large families. Parents choose to invest in quality of life rather than quantity of children. Increased opportunities for work outside of the home, especially for women and increased access to birth control leads to fewer children being born (p. 124) Q8. Women's rights are important for controlling population growth Family planning → the effort to plan the number and spacing of one's children; offers birth control and contraception options; gives women more control over their reproductive window Crisis Environmentalist- Developmental Distributists- if socioeconomic problems- lower rate Empowering women gives them more education opportunities and chances to meet empowered women that they can emulate → education helps women pursue careers, delay childbirth, and have more say in reproductive decisions Recall India video !! Q9. Poor societies have higher population growth than wealthier societies increasing affluence lowers fertility. The women are less educated, can't afford family planning, and are often forced into having children they do not want because they cannot afford birth control. This is also bad from an environmental standpoint, because poverty often leads to environmental degradation. People living in poverty may farm on land that is not good, thus degrading the soil and not being sustainable. They cut forests and deplete biodiversity Hunting for animals Affluence also affects the environment because people from affluent nations leave considerably larger per capita ecological footprints, rising consumption and energy usage = pollution. Chapter 7: Soil, Agriculture, and the Future of Food Q1: Describe patterns in global food security from 1970 to present Food security - guarantee of an adequate, safe, nutritious, and reliable food supply available to all people at all times Patterns Undernutrition receiving fewer calories than minimum dietary energy requirement Too poor to purchase food Has been falling because prices of food have fell Overnutrition Unhealthy weight gain, leading to cardiovascular disease and other health problems Growing availability of high processed foods contributes to this Will remain a problem into future Malnutrition Shortage of nutrients the body needs Lack of proteins, essential lipids,vitamins, and minerals Leads to disease Most common in developing world Two nutrient deficiencies Deficient in protein can lead to kwashiorkor Deficient in protein can lead to marasmus Iron deficiency can lead to anemia Iodine deficiency can lead to swelling of thyroid gland and brain damage Vitamin A deficiency can lead to blindness Q2: Compare and contrast methods in traditional and industrial agriculture Traditional farmers Plant polycultures - mixtures of different crops in small plots of farmland Industrial agriculture Boosted yields by intensifying irrigation and introducing synthetic fertilizers Monoculture farming more efficient but they reduce biodiversity by eliminating habitats and makes them more susceptible to bacterial and viral disease 3 examples of ecosystem services that people would have a hard time replacing Chapter 8: Biodiversity and Conservation Biology Q1: What is biodiversity? Describe three levels of biodiversity. (p.163-164) Biodiversity- the variety of life across all levels of biological organization and includes diversity in species, genes, populations, communities, and ecosystems Three levels of biodiversity: Species Diversity- the number or variety of species found in a particular region; looks at: species richness (number of species), evenness or relative abundance (degree to which species differ in numbers of individuals); species= type of organism that share certain characteristics and can breed with one another and produce fertile offspring Biodiversity exists below this level→ subspecies: populations of a species that occur in different geographic areas and differ from one another in slight ways; occurs when divergence stops short of forming a separate species Genetic Diversity- the differences in DNA composition among individuals, and this provides the raw material for adaptation to local conditions; populations with more genetic diversity are more likely to survive because the variations allow them to cope with environmental change Ecosystem Diversity- the number and variety of ecosystems, but biologists may also refer to the diversity of communities or habitats within some specified area Q2: Define the term ecosystem services. Give three examples of ecosystem services that people would have a hard time replacing if these were lost. Ecosystem services- an essential service an ecosystem provides that supports life and makes economic activity possible Examples: Ecosystems naturally purify air and water Provide for plants to be pollinated by animals Cycle nutrients Q3: What is the relationship between biodiversity and food security? Between biodiversity and pharmaceuticals? Give 3 examples of benefits of biodiversity conservation for food supplies and medicine (p.166) Biodiversity and food security Biodiversity provides the food we eat We now get 90% of our food from just 15 crop species and 8 livestock species Biodiversity and pharmaceuticals People have made medicines from plants and animals for centuries and many of today's pharmaceuticals are made from chemical compounds in wild plants Benefits for food supplies and medicine Crop varieties provide insurance against disease and drought Stabilizes Earth's climate Provides new plant species for crops/ medicines Q4: List three reasons why people suggest that biodiversity conservation is important. (p.167) Provides food, fuel, fiber, and shelter Purifies air and water Detoxifies and decomposes wastes Q5: What are the five primary causes of biodiversity loss? Give one specific example of each. Habitat Loss- Building a highway through a grassland (the organisms who live in that grassland lose their homes and therefore have to leave for other places, which decreases the biodiversity in that area) (p. 171) Pollution- Agricultural runoff containing fertilizers, pesticides, and sediments harms many terrestrial and aquatic species (p.173) Overharvesting- People have long killed elephants to extract their tusks for ivory and by 1989, 7% of African elephants were being killed each year (p. 174) Invasive species- The Nile perch was introduced as a food fish in Lake Victoria and soon spread through the vast lake, preying and driving extinct dozens of native species of cichlid fish (p. 176) Climate Change- In the Arctic, melting sea ice and other impacts are threatening polar bears and people because warming temperatures are forcing organisms to shift their geographic ranges toward the poles and upward in altitude (p.176) Q6: List three invasive species, and describe their impacts. (p.175) European gypsy moth- defoliate trees over large regions every few years European starling- became one of North America's most abundant birds Cheatgrass- crowds out other plants, uses up the soil's nitrogen, and burns readily Q7: Describe one successful accomplishment of the US Endangered Species Act. Now describe one reason some people have criticized it. In 1993, they banned the pesticide DDT. Because of it, the bald eagle, peregrine falcon, brown pelican, and other birds have recovered and are no longer listed as endangered Criticized because: some people believe the ESA imperils people's livelihoods because many landowners worry that federal officials will restrict the use of private land on which threatened or endangered species are found Q8: Explain how captive breeding can help with endangered species recovery, and give an example. Now explain why cloning could never be, in itself, an effective response to species loss. (p.180) Captive breeding- individuals are bred and raised in controlled conditions with the intent of reintroducing their progeny into the wild Captive breeding can help endangered species recovery because they can be bred in a controlled environment, where they do not have to worry about predators or disease and can thrive and be released into the wild and produce more of their species. Ex: California condor- North America's largest bird- in the early 20th century, people began to shoot them; by 1982, there were only 22 left and biologists decided to take them all into captivity. In 2014, there were 198 birds in captivity and 237 in the wild Cloning could never be an effective option because there is not an ample amount of habitats and protection in the wild for the cloned animals and having cloned animals in zoos does little good Q9: Name two reasons that a large national park like Serengeti or Yellowstone might not be adequate to effectively conserve a population of a threatened species. What solutions exist to address these reasons? (p.182) Reasons: Many of the animals still come into contact with ranchers and hunters Global warming has caused species to move toward the poles and upward, forcing them out of the national parks Solutions: Conservationists have tried to find ways to protect animals and habitats across the Greater Yellowstone Ecosystem Link protected areas across the landscape with corridors of habitat so that species can move in response to climate change Q10: Explain the notion of community-based conservation. Why have conservation advocates been turning to this approach? What challenges exist in implementing it? (p.182) Community-based conservation- how biologists actively engage local people in efforts to protect land and wildlife in their own regions Conservationists in East Africa began working with local people because they understood that in order to conserve animals and ecosystems, local people have to be stewards of the land and feel invested in conservation Challenges: Parks and reserves were created on land historically used by local people (residents were forcibly relocated) Laws against poaching deprive the people from killing wildlife (conflicts have increased between humans and wildlife) Chapter 10: Environmental Health and Toxicology Q1: What four major types of health hazards are examined by practitioners of environmental health? (p.207-208) Physical Hazards- arise from processes that occur naturally in our environment and pose risks to human life or health (ex: excessive exposure to UV radiation from sunlight which damages DNA) Chemical Hazards- include many of the synthetic chemicals that our society manufactures, such as pharmaceuticals, disinfectants, and pesticides Biological Hazards- result from ecological interactions among organisms (ex: infectious diseases) Cultural Hazards- result from our place of residence, our socioeconomic status, our occupation, or our behavioral choices; can be chosen by you or forced upon you by someone else's choices (ex: smoking cigarettes, getting second hand smoke) Q2: In what way is disease the greatest hazard that people face? What kinds of interrelationships must environmental health experts study to learn how diseases affect human health? Disease causes the vast majority of human deaths worldwide (most of them being noninfectious diseases, such as cancer or heart disease) These diseases are not spread from person to person, but are caused by lifestyle, genetics, and environmental factors Infectious diseases, although they do not take as many lives, they take more years away There are many strategies to prevent the spread infectious diseases, but they are more accessible to developed countries and the diseases can never be fully prevented Interrelationships: Understand the relationship between technology, land use, and ecology Must know how humans and disease vectors interact How climate change and habitat alteration will alter the spread of disease Q3: Where do most exposure to lead, asbestos, radon, and PBDEs occur? (p.209) Indoors Lead- lead poisoning from water pipes or leaded paint can cause cognitive problems and behavioral abnormalities Asbestos- used in the past as insulation in walls is dangerous when inhaled Radon- a radioactive gas that seeps up from the ground and can cause lung cancer PBDEs- found in computers, televisions, plastics, and furniture and are endocrine disruptors and can cause cancer and thyroid diseases Q4: List and describe the seven general categories of toxic substances described in this chapter. (p.211-212) Carcinogens- substances or types of radiation that cause cancer; can be difficult to identify because there may be a long lag time between exposure to the agent and the detectable onset of cancer and only a portion of people exposed to a carcinogen develop cancer Mutagens- substances that cause genetic mutations in the DNA of organisms; some can lead to severe problems, such as cancer or other disorders; if it occurs in an individual's sperm or egg cells, then the individual's offspring suffer the effects Teratogens- chemicals that cause harm to the unborn (ex: Thalidomide→ caused birth defects) Neurotoxins- assault the nervous system; include venoms produced by animals, heavy metals (mercury or lead) and some pesticides Allergens- overactivate the immune system, causing an immune response when one is not necessary Pathway inhibitors- toxicants that interrupt vital biochemical processes in organisms by blocking one or more steps in important biochemical pathways (ex: rat poisons) Endocrine disruptors- toxic substances that interfere with the endocrine system (which consists of chemical messengers that travel through the bloodstream to perform vital functions Q5: Explain the mechanisms within organisms that protect them from damage from toxic substance. Skins, scales, feathers Organism can store toxins in the body Q6: Describe and contrast the processes of bioaccumulation and biomagnification. Bioaccumulation- the buildup of toxicants in the tissues of an animal Biomagnification- magnification of the concentration of toxicants in an organism caused by its consumption of other organisms in which toxicants have been bioaccumulated Processes: Bioaccumulation- substances that are fat-soluble or oil-soluble are absorbed and stored in fatty tissues Biomagnification- when one organism consumes another, the predator takes in any stored toxicants and stores them in its own body Q7: What are epidemiological studies, and how are they most often conducted? Epidemiological studies- large-scale comparisons among groups of people, usually contrasting a group known to have been exposed to some hazard against a group that has not Epidemiologists track the fate of all people in the study for a long period of time (often years or decades) and measure the rate at which deaths, cancers, or other health problems occur in each group Q8: Explain the dose-response curve. Why do endocrine-disrupting chemicals such as BPA pose challenges for toxicology? Dose-response curve- curve that plots the response of test animals to different doses of a toxicant, as a result of dose-response analysis Endocrine system is vulnerable to to extremely low concentrations of chemicals Q9: What factors may affect an individual's response to a toxic substance? Genetics, health conditions, sex, age, and weight Q10: How do scientists identify and assess risks from substances and activities? Risk Assessment and Risk Management Risk assessment- the quantitative measurement of risk and the comparison of risks involved in different activities or substances (p.219) Risk management- the process of considering information from scientific risk assessment in light of economic, social, and political needs and values, in order to make decisions and design strategies to minimize risk Chapter 12: Fresh Water, Oceans, and Coasts Chapter 13: Atmospheric Sciences, Air Quality, and Pollution Control Q1. How thick is the Earth's atmosphere? Name one characteristic of the troposphere and one of the stratosphere. The atmosphere is actually only 1/100 of the Earth's diameter. The troposphere is the bottom most layer. It is relatively thin but contains ¾ of the atmosphere's mass because gravity pulls mass downward making the air denser. The stratosphere warms with altitude. Q2. Where is the ozone layer located? Describe how and why stratospheric ozone is beneficial for people, whereas tropospheric is harmful. Chapter 14: Global Climate Change Q1. Fate of solar radiation after it reaches Earth → our planet receives abt 340 watts of energy per square meter from the sun, and it naturally reflects and emits the same amount. As Earth's surface absorbs solar radiation, the surface increases in temperature and emits infrared radiation. Atmospheric gases absorb this infrared radiation. Greenhouse gases are these gases that absorb infrared radiation, and after absorbing the radiation, they re-emit infrared radiation. Some is lost to space but most travels back downward, warming the lower atmosphere and the surface, a phenomenon known as the greenhouse effect. Q2. Carbon dioxide is considered the main greenhouse gas because although it is less potent on a per-molecule basis than other greenhouse gases, it is far more abundant in the atmosphere. Greenhouse gas emissions from human activity consist mostly of CO2 and it has caused twice as much warming since the Industrial Rev. then methane and Nitrous oxide combined. The concentration of CO2 in our atmosphere is far higher than its been in 800,000 years. Why? à Most carbon is stored for long periods in the upper layers of the lithosphere, and the increased fossil fuel extraction and burning has led to large amounts of CO2 being transferred to the atmosphere. In addition, the clearing of forests and pastures is problematic because they serve as a storage for carbon. Q3. Scientists study the ancient atmosphere by using proxy indicators, which are types of indirect evidence that serve as proxies for direct measurement. For example, scientists can study trapped air bubbles in ice caps and glaciers to determine atmospheric composition, greenhouse gas concentrations, temp, snowfall, solar activity, forest fires, and volcanic eruptions during each period of time that the snow fell and formed ice. Q4. Climate models are computer programs that combine what is known about atmospheric circulation, atmosphere-ocean interactions, and feedback cycles to stimulate climate processes. If a model accurately reconstructs current climate, then we have reason to believe that it stimulates climate mechanisms realistically and can accurately predict future climate. Q5. Major trends in climate documented so far: · Species ranges are shifting towards the poles and up in elevation · Seasonal timing is shifting · Forests are being altered by drought, fire, and pest outbreaks · Droughts and flooding are leading to agricultural losses · More intense storms = more damage and loss of life Future predictions: · Ocean acidification could impact marine life and cause disappearance of coral reefs · Sea level rise will displace people · Crop yields will fall in the dry tropics and subtropics · Economic costs will outweigh benefits · Water supplies will be reduced Q6. Rising sea levels might affect millions of people à beach erosion, coastal flooding, intrusion of salt water into aquifers, and greater impacts from storm surges (Ex. Katrina and Sandy). Climate change is also affecting marine ecosystems. Ocean acidification makes ocean water more acidic and threatens marine animals who rely on carbonate ions which become less available as the ocean becomes more acidic. Also, changes to the physical system will be problematic, because orgs. Have adapted to their environments and changes will affect them. Q7. Climate change effects on: · Agriculture o growing seasons shortened, crops more susceptible to droughts and failure; o crop production will decrease, worsening hunger · Distribution of plants and animals o Global warming modifies temperature-dependent phenomena § Timing of migration, breeding o Shifts in geographic range of organisms o Animals and plants will move towards the poles or upward in elevation o 20-30% of all species will be threatened with extinction o Plants act as carbon sinks; fewer plants means more CO2 in the atmosphere · Human health o heat waves and stress can cause death, respiratory ailments, o expansion of tropical diseases, o increased mortality from storms o hunger-related ailments Q8. Largest two sources of greenhouse gas emissions in the US: burning fossil fuels and loss of carbon absorbing vegetation due to deforestation. What can we do? · Adaptation à pursue strategies that cushion ourselves from the impacts of climate change · Mitigation à alleviate or reduce the severity of the problem (ex. Improving energy efficiency) · Carbon capture à removing CO2 from emissions · Carbon storage à storing carbon under pressure · Lifestyle choices à reduce reliance on cars Q9. Two international treaties · Framework Convention on Climate Change à outlined a plan to reduce gg emissions to 1990 levels by the year 2000 through a voluntary approach · The Kyoto Protocol à after FCCC failed, this treaty was drafted which mandated signatory nations to reduce emissions of six greenhouse gases to levels below those of 1990 (US only nation not to ratify) Q10. Market approaches for reducing gg emissions: · Carbon tax à an approach in which governments charge polluters a fee for each unit of greenhouse gases they emit, this gives polluters a clear financial incentive to reduce emissions · Fee and dividend à an approach in which funds from the carbon tax, or "fee," paid to the government by polluters are transferred as a tax refund, or "dividend," to taxpayers. · Carbon neutrality à a state in which no net carbon is emitted · Geoengineering—> being considered as a drastic, last-ditch effort to reverse global warming o Ex. Sucking carbon dioxide out of the air, artificial trees, etc. Chapter 15: Nonrenewable Energy Sources, Their Impacts, and Energy Conservation Chapter 16: Renewable Energy Alternatives Chapter 17: Managing Our Waste Q1: Three Major Components of managing waste: Minimizing the amount of waste we generate Recovering discarded materials and finding ways to recycle them Disposing of waste effectively and safely Why do we practice waste management? Waste can degrade water quality, soil quality, air quality, and human health Waste also indicates inefficiency Reducing waste can save money and resources Q2: Why have some people labeled the United States "the throw away society?" Americans generate considerably more waste than people in most industrialized nations U.S. lifestyle -- excess packaging and reliance on nondurable goods How much solid waste do Americans generate? According to the EPA the US generates 251 million tons of municipal solid waste (before recovery) in 2012 1 ton per person The average american generates 4.4lbs of trash per day How does this amount compare to that of people from other countries? The U.S. generates more trash than any other industrialized nations Q3: Name several guidelines by which sanitary landfills are regulated. Landfills must be located away from wetlands and earthquake prone faults must be at least 6 m (20 ft) above the water table Bottoms and sides of sanitary and fills must be lined with heavy-duty plastic and 60-120 cm (2-4 ft) of impermeable clay to help prevent contaminants from seeping into aquifers Must have a system of pipes, ponds, and treatment facility to collect and treat leachate (liquid that results when substances from trash dissolve in water as rainwater percolates downward) Leachate treatment must continue 30 years after the landfill has been filled Describe three problems with landfills. Liners can be punctured and leachate collection systems eventually cease to be maintained Landfills are kept dry to prevent leachate but dryness slows decomposition NIMBY -- people don't want landfills near them Q4:Process of Incineration/combustion: Waste is sorted and metals are removed Metal-free waste is chopped into small pieces Burned in a furnace What happens to the resulting ash? Disposed of in hazardous waste landfills What is one drawback of incineration? Hazardous chemicals are created and released into the atmosphere --> health concerns Q5: What is composting? The conversion of organic waste into mulch or humus through natural decomposition How does composting reduce the waste stream? ⅕ of the U.S. waste stream is made up of materials that can easily be composted It reduces landfill waste, enriches soil, enhances soil biodiversity, helps soil to resist erosion, makes for healthier plants and more pleasing gardens, and reduces the need for chemical fertilizers Q6: Three elements of a sustainable process of recycling? Collection and processing of recyclable materials by municipalities and businesses Use of recyclables by industry to manufacture new products Consumer purchase of products made from recycled materials Q7: Describe the goals of industrial ecology. Seeks to redesign industrial systems to reduce resource inputs and to maximize both physical and economic efficiency Would reshape the industry so that nearly everything produced in a manufacturing process is used, either within that process or in a different one Q8: Four criteria that define hazardous waste: Ignitable Corrosive Reactive Toxic What makes heavy metals and synthetic organic compounds particularly hazardous? Synthetic organic compounds are toxic because they are readily absorbed through the skin and can act as mutagens, carcinogens, teratogens, and endocrine disruptors Heavy metals that are fat-soluble and break down slowly are prone to bioaccumulate and biomagnify Q9: Large sources of hazardous waste: Industry Produces huge amounts of hazardous waste Waste generation and disposal is highly regulated Mining Households Paints, batteries, oils, solvents, cleaners, pesticides Other Small businesses Agriculture Three ways to dispose of hazardous waste: Landfills Surface impoundments Injection wells Q10: What is the Superfund program? Program under the Comprehensive Environmental Response Compensation and Liability Act (CERCLA) that identifies polluted sites, take action to protect groundwater and clean up the pollution How does it work? Once a superfund site is identified, EPA scientists evaluate how near the site is to homes, whether wastes are confined or likely to spread, and whether the pollution threatens drinking water supplies Sites judged to be harmful are placed on the National Priorities List, ranked by the level of risk to human health that they pose Cleanup proceeds as funds are available Chapter 18: The Urban Environment: Creating Sustainable Cities Q1: What factors lie behind the shift of population from rural areas to urban areas? Location: Climate Topography Configuration of waterways What types of nations are experiencing the fastest urban growth today, and why? Developing nations-- rural people are streaming to cities in search of jobs and urban lifestyles or to escape ecological degradation in the countryside Q2 Why have so many city dwellers in the United States and other developed nations moved into suburbs? More space Better economic opportunities Cheaper real estate Less crime Better schools for children Q3 Give two definitions of sprawl. Describe five negative impacts that have been suggested to result from sprawl. The spread of low-density urban or suburban development outward from an urban center Negative impacts Transportation problems Pollution because of more automobile use Obesity because people driving instead of walking Land - more land gets used Economics - drains tax money into infrastructure for new development Q4 What are city planning and regional planning? City Planning: mappin gout development options, transportation needs, public parks, and other matters Rural Planning: city planning but on a larger scale Contrast planning with zoning. Zoning is a key tool for planning Zoning: practice of classifying areas for different types of development and land use Involves government restriction on the use of personal property rights Represents a top-down constraint on personal property rights Give examples of some of the suggestions made by early planners Rebuild the harbor: Dredge the river channel Construct new docks, bridges, tunnels, and a waterfront railroad Superimpose wide radial boulevards on the old city street grid Establish city centers downtown Greatly expand the number of parks Q5 How are some people trying to prevent or slow sprawl? Smart Growth: "building up, not out" -- focusing development and economic investment in existing urban centers and favoring multi-story shop-houses and high-rises Mix land uses Take advantage of compact building desing Create a range of housing opportunities and choices Create walkable neighborhoods Foster destinctive, attractive communities with a strong sense of place Preserve open space, f New Urbanism: seeks to design walkable neighborhoods with homes, businesses, schools, and other amenities all close together for convenience Describe some key elements of "smart growth, " What effects, positive and negative, do urban growth boundaries tend to have? Q6 Describe several apparent benefits of rail transit systems. What is a potential drawback Q7How are parks thought to make urban areas more livable? Give three examples of types of parks or public spaces Q8 What is a green building? Describe several features a LEED-certified building may have green building- structures that are built from sustainable materials, limit their use of energy and water, minimize health impacts on their occupants, control pollution and recycle waste. LEED Certified building features Photovoltaic Solar Panels- produce electricity Insulation- reduces energy loss Q9 Describe the connection between urban ecology and sustainable cities. List three actions a city can take to enhance its sustainability Urban ecology- Sustainable cities- Q10: Name two positive effects of urban centers on the natural environment Land Preservation- People pack densely together in cities, more land outside cities is left undeveloped. Innovation- Cities promote a flourishing cultural life and by mixing diverse people and influences, spark innovation and creativity. The urban environment can promote education and scientific research, and cities have long been viewed as engines of technological and artistic inventiveness

Chapter 1-5

• Our Island, Earth o Our Environment surrounds us Environment: The sum total of our surroundings, including all of the living things and nonliving things with which we interact. o Environmental science explores our interactions with the world Environmental science: the scientific study of how the natural works, how our environment affects us, and how we affect our environment. o We rely on natural resources Natural resources: the substances and energy sources we take from our environment and that we rely on to survive. Renewable natural resources: natural resources that are replenished over short periods of time. Nonrenewable natural resources: natural resources that have a finite supply and are formed far more slowly than we use them. Once depleted nonrenewable resources is no longer available Ecosystem services: an essential service and ecosystem provides that supports life and makes economic activity possible. • For example, ecosystem naturally purify air and water, cycle nutrients, provide for plants to be pollinated by animals, and received and recycle the waste o Population growth amplifies our impact Agricultural revolution: people began to grow crops, domesticate animals, and live sedentary lives on farms and in villages, they produced more food to meet their nutritional needs and began having more children Industrial revolution: a shift from rural life, animal powered agriculture, and handcrafted goods toward an urban society provisioned by mass production of factory-made goods and powered by fossil fuels Fossil fuels: nonrenewable energy sources such as coal, oil, and natural gas o Resource consumption exerts social and environmental pressures Ecological footprint: expresses the cumulative area of biologically productive land and water required to provide the resources a person or population consumes and to dispose of or recycle the waste the person or population produces Overshoot: the amount by which humanity's resource use, as measured by its ecological footprint, has surpassed Earth's long-term capacity to support us o Environmental science can help us avoid past mistakes • The Nature of Environmental Science o Environmental science is interdisciplinary Interdisciplinary: bringing techniques, perspectives, and research results from multiple disciplines together into a broad synthesis Natural sciences: disciplines that examine the natural world Social sciences: disciplines that address human interactions and institutions Environmental studies: an academic environmental science program that emphasizes the social sciences as well as the natural sciences o Environmental science is not the same as environmentalism Environmentalism: the social movement dedicated to protecting the natural world- and, by extension, people from undesirable changes brought about by human actions • The Nature of Science Science: systematic process for learning about the world and testing our understanding of it o Scientists test ideas by critically examining evidence Observational science/ descriptive science: research in which scientists gather basic info about organisms, materials, systems, or processes that are not yet well known Hypothesis-driven science: research that proceeds in a more targeted and structured manner, using experiments to test hypotheses within a framework traditionally known scientific method o The scientific method is a traditional approach to research Scientific method: a technique for testing ideas with observations • Make observations • Ask questions • Develop a hypothesis o Hypothesis: a statement that attempts to explain a phenomenon or answer a scientific question • Make predictions o Prediction: specific statements that can be directly and unequivocally tested • Test the prediction o Experiment: an activity designed to test the validity of a prediction or a hypothesis o Variables: conditions that can change o Independent variable: a variable the scientist manipulates o Dependent variable: the variable that is affected by manipulation of the independent variable in an experiment o Controlled experiment: an experiment in which a treatment is compared against a control in order to test the effect of a variable o Control: the portion of an experiment in which a variable has been left unmanipulated, to serve as a point of comparison with the treatment o Treatment: the portion of an experiment in which a variable has been manipulated in order to test its effects. Compare control. • Analyze and interpret results o Data: information, generally quantitative information o We test hypotheses in different ways Correlation: a statistical association among variables o The scientific process continues beyond the scientific method Peer Review • Peer Review: the process by which a manuscript submitted for publication in an academic journal is examined by specialists in the field, who provide comments and criticism (generally anonymously) judge whether the work merits publication in the journal. Conference presentations Grants and funding Repeatability Theories • Theories: a widely accepted, well-tested explanation of one or more cause-and-effect relationships that has been extensively validated by a great amount of research o Science undergoes paradigm shifts Paradigm: A dominant philosophical and theoretical framework within a scientific discipline. • Environmental Ethics Ethics: The academic study of good and bad, right and wrong. The term can also refer to a person's or group's set of moral principles or values. Relativists: An ethicist who maintains that ethics do and should vary with social context. Compare universalist. Universalists: An ethicist who maintains that there exist objective notions of right and wrong that hold across cultures and situations. Compare relativist. Ethical standards: A criterion that helps differentiate right from wrong. o Environmental ethics pertains to people and the environment Anthropocentrism: A human-centered view of our relationship with the environment. Compare biocentrism and ecocentrism. Biocentrism: A philosophy that ascribes relative values to actions, entities, or properties on the basis of their effects on all living things or on the integrity of the biotic realm in general. The biocentrist evaluates an action in terms of its overall impact on living things, including—but not exclusively focusing on—human beings. Compare anthropocentrism and ecocentrism. Ecocentrism: A philosophy that considers actions in terms of their damage or benefit to the integrity of whole ecological systems, including both living and nonliving elements. For an ecocentrist, the well-being of an individual is less important than the long-term well-being of a larger integrated ecological system. Compare anthropocentrism and biocentrism. o Conservation and preservation arose with 20th century John Muir: Scottish immigrant to the United States who eventually settled in California and made the Yosemite Valley his wilderness home. Today, he is most strongly associated with the preservation ethic. He argued that nature deserved protection for its own inherent values but also claimed that nature facilitated human happiness and fulfillment. Gifford Pinchot: The first professionally trained American forester, Pinchot helped establish the U.S. Forest Service. Today, he is the person most closely associated with the conservation ethic. Conservation ethic: An ethic holding that people should put natural resources to use but also have a responsibility to manage them wisely. Compare preservation ethic. o Aldo Leopold's land ethic inspires many people Aldo Leopold: American scientist, scholar, philosopher, and author. His book The Land Ethic argued that humans should view themselves and the land itself as members of the same community and that humans are obligated to treat the land ethically. o Environmental justice seeks fair treatment for all people Environmental justice: The fair and equitable treatment of all people with respect to environmental policy and practice, regardless of their income, race, or ethnicity. Responds to the perception that minorities and the poor suffer more pollution than whites and the rich. • Sustainability and Our future Sustainability: A guiding principle of environmental science, entailing conserving resources, maintaining functional ecological systems, and developing long-term solutions, such that Earth can sustain our civilization and all life for the future, allowing our descendants to live at least as well as we have lived. Natural capital: Earth's accumulated wealth of resources. o Population and consumption drive environmental impact o Energy choices will shape our future o Sustainable solutions abound Sustainable development: development that satisfies our current needs without compromising the future availability of natural capital or our future quality life o Student are promoting solutions on campus Campus sustainability: A term encompassing a wide variety of efforts by students, faculty, staff, and administrators of colleges and universities to make campus operations more sustainable. Includes efforts toward energy efficiency, water efficiency, emission reductions, transportation improvements, sustainable dining, landscaping improvements, renewable energy, curricular changes, and more. Chapter 2 • fersEarth's Environmental Systems System: a network of relationships among parts, elements, or components that interact with and influence one another through the exchange of energy, matter, or information Lithosphere: the rock and sediment beneath our feet, the planet's uppermost mantle and crust Atmosphere: composed of the air surrounding our planet Hydrosphere: encompasses all water-salt or fresh; liquid, ice, or vapor- in surface bodies, underground, and in the atmosphere Biosphere: consists of all planet's organisms and the abiotic (non-living) portions of the environment with which they interact o Systems involve feedback loops Feedback loop: a system's output can serve as input to the same system, a circular process Negative feedback loop: A feedback loop in which output of one type acts as input that moves the system in the opposite direction. The input and output essentially neutralize each other's effects, stabilizing the system. Compare positive feedback loop. Dynamic equilibrium: The state reached when processes within a system are moving in opposing directions at equivalent rates so that their effects balance out. Homeostasis: The tendency of a system to maintain constant or stable internal conditions. Positive feedback loops: A feedback loop in which output of one type acts as input that moves the system in the same direction. The input and output drive the system further toward one extreme or another. Compare negative feedback loop. o Environmental Systems Interact Runoff: The water from precipitation that flows into streams, rivers, lakes, and ponds, and (in many cases) eventually to the ocean. Airshed: The geographic area that produces air pollutants likely to end up in a waterway. Eutrophication: The process of nutrient enrichment, increased production of organic matter, and subsequent ecosystem degradation in a water body. • Matter, Chemistry, and the Environmental Matter: All material in the universe that has mass and occupies space. See law of conservation of matter. Chemistry: The study of the different types of matter and how they interact. Law of conservation of matter: The physical law stating that matter may be transformed from one type of substance into others, but that it cannot be created or destroyed o Atoms and elements are chemical building blocks Element: a fundamental type of matter, a chemical substance with a given set of properties, that cannot be chemically broken down into substances with either properties Atoms: the smallest unit that maintains the chemically properties of an element Protons: positively charged particles in the atom's nucleus (its dense center) Neutrons: particles lacking electric charge in their nuclei Electrons: A negatively charged particle that moves around the nucleus of an atom. • ((hydrogen, oxygen, silicon, carbon, and nitrogen are abundant elements on the planet))\ • ((phosphorous, nitrogen, calcium, and carbon are nutrients because they are elements that organisms need for survival)) • nutrients: An element or compound that organisms consume and require for survival. Isotopes: One of several forms of an element having differing numbers of neutrons in the nucleus of its atoms. Chemically, isotopes of an element behave almost identically, but they have different physical properties because they differ in mass. Ions: An electrically charged atom or combination of atoms. o Atoms bond to form molecules and compounds Molecules: A combination of two or more atoms. Chemical formula: A shorthand way to indicate the type and number of atoms in a molecule using numbers and chemical symbols. Compound: A molecule whose atoms are composed of two or more elements. Water: A compound composed of two hydrogen atoms bonded to one oxygen atom, denoted by the chemical formula H2O. Carbon dioxide: a compound that consists of one carbon atom bonded to two oxygen atoms C2O Ionic bonds: A type of chemical bonding where electrons are transferred between atoms, creating oppositely charged ions that bond due to their differing electrical charges. Table salt, or sodium chloride, is formed by the bonding of positively charged sodium ions with negatively charged chloride ions. Covalent bonds: A type of chemical bonding where atoms share electrons in chemical bonds. An example is a water molecule, which forms when an oxygen atom shares electrons with two hydrogen atoms. Solution: elements, molecules, and compounds that come together without chemically bonding Methane: a colorless gas produced primarily by anaerobic decomposition. The major constituent of natural gas and greenhouse gas that is molecules for molecule more potent than carbon dioxide Ozone: a molecule consisting of three atoms of oxygen. Absorbs UV radiation in the stratosphere o The pH scale describes acids and bases Acidic: the property of a solution in which the concentration of hydrogen ions is greater than the concentration of hydroxide ions Neutral: 7 pure water Basic: the property of a solution in which the concentration of hydroxide ions is greater than the concentration of hydrogen ions. o Matter is composed of organic and inorganic compounds organic compounds: A compound made up of carbon atoms (and, generally, hydrogen atoms) joined by covalent bonds and sometimes including other elements, such as nitrogen, oxygen, sulfur, or phosphorus. The unusual ability of carbon to build elaborate molecules has resulted in millions of different organic compounds showing various degrees of complexity. Hydrocarbon: An organic compound consisting solely of hydrogen and carbon atoms. o Macromolecules are building blocks of life Polymers: A chemical compound or mixture of compounds consisting of long chains of repeated molecules. Important biological molecules, such as DNA and proteins, are examples of polymers. Macromolecules: A very large molecule, such as a protein, nucleic acid, carbohydrate, or lipid. Carbohydrates: An organic compound consisting of atoms of carbon, hydrogen, and oxygen. Proteins: A macromolecule made up of long chains of amino acids. Nucleic acids: A macromolecule that directs the production of proteins. Includes DNA and RNA. Genes: A stretch of DNA that represents a unit of hereditary information. Lipids: chemically diverse groups of compounds, classified together because they do not dissolve in water (fats and oils) Cells: The most basic organizational unit of organisms. • Energy Fundamentals Energy: The capacity to change the position, physical composition, or temperature of matter; a force that can accomplish work Potential energy: Energy of position. Compare kinetic energy. Kinetic energy: Energy of motion. Compare potential energy. Chemical energy: Potential energy held in the bonds between atoms. o Energy is always conserved but it changes in quality First law of thermodynamics: The physical law stating that energy can change from one form to another, but cannot be created or lost. The total energy in the universe remains constant and is said to be conserved. Second law of thermodynamics: The physical law stating that the nature of energy tends to change from a more-ordered state to a less-ordered state; that is, entropy increases. o Light Energy from the sun powers most living systems Autotrophs (primary producer): An organism that can use the energy from sunlight to produce its own food. Includes green plants, algae, and cyanobacteria. Producer: An organism that uses energy from sunlight to produce its own food. Includes green plants, algae, and cyanobacteria. See autotroph. Photosynthesis: The process by which autotrophs produce their own food. Sunlight powers a series of chemical reactions that convert carbon dioxide and water into sugar (glucose), thus transforming low-quality energy from the sun into high-quality energy the organism can use. Compare cellular respiration. o Cellular respiration release chemical energy Cellular respiration: The process by which a cell uses the chemical reactivity of oxygen to split glucose into its constituent parts, water and carbon dioxide, and thereby release chemical energy that can be used to form chemical bonds or to perform other tasks within the cell. Compare photosynthesis. Heterotrophs (consumer): An organism that consumes other organisms. Includes most animals, as well as fungi and microbes that decompose organic matter. • Ecosystems ecosystem: consists of all organisms and nonliving entities that occur and interact in a particular area at a particular time o Energy flows and matter cycles through ecosystems estuary: An area where a river flows into the ocean, mixing fresh water with salt water. o Sunlight is converted to chemical energy in biomass Primary production: The conversion of solar energy to the energy of chemical bonds in sugars during photosynthesis, performed by autotrophs. Compare secondary production. Gross primary production: The energy that results when autotrophs convert solar energy (sunlight) to energy of chemical bonds in sugars through photosynthesis. Autotrophs use a portion of this production to power their own metabolism, which entails oxidizing organic compounds by cellular respiration. Compare net primary production. Net primary production: The energy or biomass that remains in an ecosystem after autotrophs have metabolized enough for their own maintenance through cellular respiration. Net primary production is the energy or biomass available for consumption by heterotrophs. Compare gross primary production; secondary production. Productivity: The rate at which plants convert solar energy (sunlight) to biomass. Ecosystems whose plants convert solar energy to biomass rapidly are said to have high productivity. See net primary productivity; gross primary production; net primary production. Net primary productivity: The rate at which net primary production is produced. See productivity; gross primary production; net primary production; secondary production. o Ecosystems interact across landscapes Landscape ecology: The study of how landscape structure affects the abundance, distribution, and interaction of organisms. This approach to the study of organisms and their environments at the landscape scale focuses on broad geographical areas that include multiple ecosystems. Patches: In landscape ecology, spatial areas within a landscape. Depending on a researcher's perspective, patches may consist of habitat for a particular organism, or communities, or ecosystems. An array of patches forms a mosaic. Conversation biologist: A scientific discipline devoted to understanding the factors, forces, and processes that influence the loss, protection, and restoration of biodiversity within and among ecosystems. o Modeling helps ecologists understand systems Model: A simplified representation of a complex natural process, designed by scientists to help understand how the process occurs and to make predictions. Ecological modeling: the practice of constructing and testing models that aim to explain and predict how ecological systems function o Ecosystem services sustain our world Ecosystem services: an essential service an ecosystem provides that supports life and makes economic activity possible. For example, ecosystems naturally purify air and water, cycle nutrients, provide for plants to be pollinated by animals, and receive and recycle waste we generate • Biogeochemical cycles o Nutrients circulate through ecosystems in biogeochemical cycles Nutrient cycles (biogeochemical cycles): The comprehensive set of cyclical pathways by which a given nutrient moves through the environment. o The water cycle affects all other cycles Hydrologic cycle: The flow of water—in liquid, gaseous, and solid forms—through our biotic and abiotic environment. Also called the water cycle. Evaporation: the conversion of a substance from a liquid to a gaseous form Transpiration: the release of water vapor by plants, through their leaves Precipitation: Water that condenses out of the atmosphere and falls to Earth in droplets or crystals. Infiltration: permeation of a liquid into something by filtration Aquifers: a body of permeable rock that can contain or transmit groundwater. Groundwater: water held underground in the soil or in pores and crevices in rock Water table: The upper limit of groundwater held in an aquifer. o The carbon cycle circulates a vital organic nutrient Carbon cycle: A major nutrient cycle consisting of the routes that carbon atoms take through the nested networks of environmental systems. o The nitrogen cycle involves specialized bacteria Nitrogen cycle: A major nutrient cycle consisting of the routes that nitrogen atoms take through the nested networks of environmental systems. Nitrogen fixation: The process by which inert nitrogen gas combines with hydrogen to form ammonium ions (NH4+), which are chemically and biologically active and can be taken up by plants Nitrogen- fixing bacteria: Bacteria that live independently in the soil or water, or those that form mutualistic relationships with many types of plants and provide nutrients to the plants by converting gaseous nitrogen to a usable form Nitrification: The conversion by bacteria of ammonium ions (NH4+) first into nitrite ions (NO2-) and then into nitrate ions (NO3) Denitrifying bacteria: Bacteria that convert the nitrates in soil or water to gaseous nitrogen and release it back into the atmosphere Denitrification: chiefly of bacteria) remove the nitrates or nitrites from (soil, air, or water) by chemical reduction. Industrial fixation: o The phosphorus cycle circulates a limited nutrient Phosphorus cycle: A major nutrient cycle consisting of the routes that phosphorus atoms take through the nested networks of environmental systems. o Tackling nutrient enrichment requires diverse approaches Reducing fertilizer use on farms and lawns and timing its application to reduce water runoff Planting and maintaining vegetation "buffers" around streams to trap nutrient and sediment runoff Using natural and constructed wetlands to filter storm water and farm runoff Improving tech in sewage treatment plants to enhance nitrogen and phosphorus capture Upgrading storm water systems to capture runoff from roads and parking lots Reducing fossil fuel combustion to minimize atmospheric inputs of nitrogen to waterways o A systemic approach to restoration of hope for Chesapeake Bay Chapter 5 • Economics and the Environment Economy: A social system that converts resources into goods and services. Economics: The study of how we decide to use scarce resources to satisfy demand for goods and services. o Economies rely on goods and services from the environment o Economic theory moved from "invisible hand" to supply and demand Classical economics: Founded by Adam Smith, the study of the behavior of buyers and sellers in a capitalist market economy. Holds that individuals acting in their own self-interest may benefit society, provided that their behavior is constrained by the rule of law and by private property rights and operates within competitive markets. See also neoclassical economics. Neoclassical economies: A mainstream economic school of thought that explains market prices in terms of consumer preferences for units of particular commodities and that uses cost-benefit analysis. Compare ecological economics; environmental economics. Cost-benefit analysis: A method commonly used by neoclassical economists, in which estimated costs for a proposed action are totaled and then compared to the sum of benefits estimated to result from the action. o Neoclassical economics has environmental consequences Replacing resources External Costs • External cost: A cost borne by someone not involved in an economic transaction. Examples include harm to citizens from water pollution or air pollution discharged by nearby factories. o Health problems o Declines in resources o Aesthetic damage o Declining real estate values Discounting Growth • Economic growth: An increase in an economy's activity—that is, an increase in the production and consumption of goods and services. o How sustainable is economic growth? Environmental economies: A developing school of economics that modifies the principles of neoclassical economics to address environmental challenges. Most environmental economists believe that we can attain sustainability within our current economic systems. Compare ecological economics; neoclassical economics. Ecological economics: A developing school of economics that applies the principles of ecology and systems thinking to the description and analysis of economies. Compare environmental economics; neoclassical economics. Steady-state economies: An economy that does not grow or shrink but remains stable. o We can assign monetary value to ecosystem good and services Nonmarket value: A value that is not usually included in the price of a good or service. o We can measure progress with full cost accounting Gross Domestic Product (GDP): The total monetary value of final goods and services produced in a country each year. GDP sums all economic activity, whether good or bad. Compare Genuine Progress Indicator (GPI). Genuine Progress Indicator: An economic indicator that attempts to differentiate between desirable and undesirable economic activity. The GPI accounts for benefits such as volunteerism and for costs such as environmental degradation and social upheaval. Compare Gross Domestic Product (GDP). Full cost accounting/ true cost accounting: An accounting approach that attempts to summarize all costs and benefits by assigning monetary values to entities without market prices and then generally subtracting costs from benefits. Examples include the Genuine Progress Indicator, the Happy Planet Index, and others. Also called true cost accounting. o Markets Can Fail Market failure: The failure of markets to take into account the environment's positive effects on economies (for example, ecosystem services) or to reflect the negative effects of economic activity on the environment and thereby on people (external costs). • Environmental Policy: An Overview Policy: A rule or guideline that directs individual, organizational, or societal behavior. Public Policy: Policy made by governments, including those at the local, state, federal, and international levels; it consists of legislation, regulations, orders, incentives, and practices intended to advance societal welfare. See also environmental policy. Environmental policy: Public policy that pertains to human interactions with the environment. It generally aims to regulate resource use or reduce pollution to promote human welfare and/or protect natural systems. o Environmental policy addresses issues of fairness and resource use Why governments intervene: • To provide social services • To provide a safety net • To eliminate unfair advantages held by single buyers or sellers • To manage publicly held resources • To minimize pollution and other threats to health and quality of life ((end)) • Tragedy of the commons o Tragedy of the commons: The process by which publicly accessible resources open to unregulated use tend to become damaged and depleted through overuse. Coined by Garrett Hardin and widely applicable to resource issues. • Free riders o Free riders: A party that fails to invest in controlling pollution or carrying out other environmentally responsible activities and instead relies on the efforts of other parties to do so. For example, a factory that fails to control its emissions gets a "free ride" on the efforts of other factories that do make the sacrifices necessary to reduce emissions. • External cost o Various factors can obstruct environmental policy o Science informs policy but it sometimes disregarded • US Environmental Law and Policy o The federal government's three branches shape policy Legislation: Statutory law. Regulation: A specific rule issued by an administrative agency, based on the more broadly written statutory law passed by Congress and enacted by the president. o Early US environmental policy promoted development First Period: 1780s- late 1800s: General Land Ordinances of 1785 and 1787 Basically took land from Native Americans o The Second wave of US environmental policy encouraged conservation In the late 1800s Aimed to alleviate some of the environmental impacts of westward expansion o The third wave responded to pollution 20th century driven my technology o Passage of NERPA and creation of EPA were milestones National Environmental Policy Act (NERPA): A U.S. law enacted on January 1, 1970, that created an agency called the Council on Environmental Quality and required that an environmental impact statement be prepared for any major federal action. Environmental impact statement (EIS): A report of results from detailed studies that assess the potential effects on the environment that would likely result from development projects or other actions undertaken by the government. Environmental Protection Agency (EPA): An administrative agency charged with conducting and evaluating research, monitoring environmental quality, setting standards, enforcing those standards, assisting the states in meeting standards and goals for environmental protection, and educating the public. o Social context for policy evolves o Environmental policy advances today on the international stage • International Environmental Policy o Globalization makes international institutions vital Globalization: The process by which the world's societies have become more interconnected, linked by trade and communication technologies in countless ways. o International law includes customary law and conventional law Customary law: International law that arises from long-standing practices, or customs, held in common by most cultures. Compare conventional law. Conventional law: International law that arises from conventions, or treaties, that nations agree to enter into. Compare customary law. North American Free Trade Agreement (NAFTA): A 1994 treaty among Canada, Mexico, and the United States that reduced or eliminated barriers to trade (such as tariffs) among these nations. Side agreements were negotiated to minimize the degree to which protections for workers and the environment were undermined. o Several organizations shape international environment policy The United Nations • The United Nations: Organization founded in 1945 to promote international peace and to cooperate in solving international economic, social, cultural, and humanitarian problems. The World Bank • The World Bank: Institution founded in 1944 that serves as one of the globe's largest sources of funding for economic development, including such major projects as dams, irrigation infrastructure, and other undertakings. The World Trade Organization • The World Trade Organization: Organization based in Geneva, Switzerland, that represents multinational corporations and promotes free trade by reducing obstacles to international commerce and enforcing fairness among nations in trading practices. Nongovernmental organizations • Nongovernmental organizations: An organization not affiliated with any national government, and frequently international in scope, that pursues a particular mission or advocates for a particular cause. • Approaches to Environmental policy o Policy can follow three approaches Lawsuits of the court Command-and-control policy • Command-and-control policy: A top-down approach to policy, in which a legislative body or a regulating agency sets rules, standards, or limits and threatens punishment for violations of those limits. Economic policy tools o Green taxes discourage undesirable activities Green taxes: A levy on environmentally harmful activities and products aimed at providing a market-based incentive to correct for market failure. Compare subsidy. Polluter-pays principle: Principle specifying that the party responsible for producing pollution should pay the costs of cleaning up the pollution or mitigating its impacts. o Subsidies promote certain activities Subsidy: A government grant of money or resources to a private entity, intended to support and promote an industry or activity. o Eco labeling empowers consumers Ecolabeling: The practice of designating on a product's label how the product was grown, harvested, or manufactured, so that consumers are aware of the processes involved and can judge which brands use more sustainable processes. o Emissions trading can produce cost-effective results Emissions trading: The practice of buying and selling government-issued marketable emissions permits to conduct environmentally harmful activities. Under a cap-and-trade system, the government determines an acceptable level of pollution and then issues permits to pollute. A company receives credit for amounts it does not emit and can then sell this credit to other companies. Compare cap-and-trade. Cap-and-trade: An emissions trading system in which government determines an acceptable level of pollution and then issues polluting parties permits to pollute. A company receives credit for amounts it does not emit and can then sell this credit to other companies. o Market incentives are diverse at the local level • Sustainable Development Sustainable development: Development that satisfies our current needs without compromising the future availability of natural capital or our future quality of life. o Sustainable development involves environmental protection, economic well-being, and social equity o Sustainable development is global Chapter 3: Evolution, Biodiversity, and Population Ecology • Evolution: The Source of Earth's Biodiversity o Natural Selection Shapes Organisms Natural selection: The process by which traits that enhance survival and reproduction are passed on more frequently to future generations of organisms than traits that do not, thus altering the genetic makeup of populations through time. Natural selection acts on genetic variation and is a primary driver of evolution. Adaption: (1) The process by which traits that lead to increased reproductive success in a given environment evolve in a population through natural selection. (2) See adaptive trait. o Selection acts on genetic variation Convergent evolution: the evolutionary process by which very unrelated species acquire similar traits as they adapt to selective pressures from similar environments o Evidence of Selection is all around us Charles Darwin: English naturalist who proposed the concept of natural selection as a mechanism for evolutionand as a way to explain the great variety of living things. Compare Wallace, Alfred Russel. Alfred Russel Wallace: English naturalist who proposed, independently of Charles Darwin, the concept of natural selection as a mechanism for evolution and as a way to explain the great variety of living things. Artificial selection: Natural selection conducted under human direction. Examples include the selective breeding of crop plants, pets, and livestock. o Understanding Evolution is Vital for Modern Society o Evolution Generates Biodiversity Biological diversity/biodiversity: The variety of life across all levels of biological organization, including the diversity of species, their genes, their populations, and their communities. o Speciation Produces New Types of Organisms Speciation: The process by which new species are generated. o We can Infer the History of Life's diversification Phylogenetic trees: A treelike diagram that represents the history of divergence of species or other taxonomic groups of organisms. o Fossils Reveal Life's History Fossil: The remains, impression, or trace of an animal or plant of past geological ages that has been preserved in rock or sediments. Extinction: The disappearance of an entire species from Earth. Compare extirpation. o Some species are especially vulnerable to extinction o Earth has seen episodes of mass extinction Mass extinction events: The extinction of a large proportion of the world's species in a very short time period due to some extreme and rapid change or catastrophic event. Earth has seen five mass extinction events in the past half-billion years. o The sixth mass extinction is upon us • Ecology and the Organism Ecology: The science that deals with the distribution and abundance of organisms, the interactions among them, and the interactions between organisms and their abiotic environments. o We study ecology at several levels Biosphere: The sum total of all the planet's living organisms and the abiotic portions of the environment with which they interact. Ecologist: an expert in or student of ecology: Population ecology: The study of the quantitative dynamics of population change and the factors that affect the distribution and abundance of members of a population Community: In ecology, an assemblage of populations of organisms that live in the same place at the same time. Community ecology: The scientific study of patterns of species diversity and interactions among species, from one-to-one interactions to complex interrelationships involving entire communities Ecosystems: All organisms and nonliving entities that occur and interact in a particular area at the same time. Ecology: The science that deals with the distribution and abundance of organisms, the interactions among them, and the interactions between organisms and their abiotic environments. Landscape ecology: The study of how landscape structure affects the abundance, distribution, and interaction of organisms. This approach to the study of organisms and their environments at the landscape scale focuses on broad geographical areas that include multiple ecosystems. o Habitat, niche, and specialization are key concepts in ecology Habitat: The specific environment in which an organism lives, including both biotic and abiotic factors. Habitat use: The process by which organisms use habitats from among the range of options they encounter. Habitat selection: The process by which organisms select habitats from among the range of options they encounter. Niche: The functional role of a species in a community. Specialist: a person who concentrates primarily on a particular subject or activity; a person highly skilled in a specific and restricted field. Generalist: a person competent in several different fields or activities: • Population Ecology o Populations show features that help predict their dynamics Population size • Population size: The number of individual organisms present at a given time in a population. Population density • Population density: The number of individuals within a population per unit area. Compare population size Population distribution • Population distribution: The spatial arrangement of organisms within a particular area. Sex ratio • Sex ratio: The proportion of males to females in a population. Age structure • Age structure: o We can Measure Population Growth Demographer: A social science that applies the principles of population ecology to the study of statistical change in human populations. Population change is determined by four factors: • Natality: births within the population • Mortality: deaths within the population • Immigration: arrival of individuals from outside the population • Emigration: departure of individuals from the population • Rate of natural increase: The rate of change in a population's size per unit time (generally expressed in percent per year), taking into accounts births, deaths, immigration, and emigration. Compare rate of natural increase. • Population growth rate: The rate of change in a population's size per unit time (generally expressed in percent per year), taking into accounts births, deaths, immigration, and emigration. Compare rate of natural increase. o Unregulated populations increase by exponential growth Exponential growth: The increase of a population (or of anything) by a fixed percentage each year. o Limiting Factors Restrain Growth Limiting factors: A physical, chemical, or biological characteristic of the environment that restrains population growth. Carrying capacity: The maximum population size that a given environment can sustain. Logistic growth: A plot that shows how the initial exponential growth of a population is slowed and finally brought to a standstill by limiting factors. Density-dependent: The condition of a limiting factor whose effects on a population increase or decrease depending on the population density. Compare density-independent factor. Density-independent: The condition of a limiting factor whose effects on a population are constant regardless of population density. Compare density-dependent factor. o Carrying capacities can change • Conserving Biodiversity o Innovative solutions are working o Climate change poses an extra challenge Chapter 4: Species Interaction • Species Interactions o Competition Can Occur When Resources are limited Competition: relationship in which multiple organisms seek the same limited resource Resource partitioning: the process by which species adapt to competition by evolving to use slightly different resources, thus minimizing interference with one another o Predators Kill and Consume Prey Predation: The process in which one species (the predator) hunts, tracks, captures, and ultimately kills its prey. o Parasites Exploit Living Hosts Parasitism: A relationship in which one organism, the parasite, depends on another, the host, for nourishment or some other benefit while simultaneously doing the host harm. Compare mutualism. o Herbivores Exploit Plants Herbivory: the consumption of plants by animals. o Mutualists Help One Another Mutualism: A relationship in which all participating organisms benefit from their interaction. Compare parasitism. Symbiosis: a relationship between different species of organisms that live in close physical proximity. People often use the term "symbiosis" where referring to a mutualism, but symbiotic relationships can be either parasitic or mutualistic Pollination: A plant-animal interaction in which one organism (for example, a bee or a hummingbird) transfers pollen (containing male sex cells) from flower to flower, fertilizing ovaries (containing female sex cells) that grow into fruits with seeds. • Ecological Communities Community: In ecology, an assemblage of populations of organisms that live in the same place at the same time. o Energy passes among trophic level Trophic level: Rank in the feeding hierarchy of a food chain. Organisms at higher trophic levels consume those at lower trophic levels. • Producers (autotroph): an organism that uses energy from sunlight to produce its own food. Includes green plants, algae, and cyanobacteria • Consumers: • Detritivores and Decomposers: an organism such as a millipede or soil insect that scavenges the waste products or dead bodies of other community members...........organism, such as fungus or bacterium, that breaks down leaf litter and other nonliving matter into simple constituents that can be taken up and used by plants o Energy, Numbers, and Biomass Decrease at Higher Trophic Levels Biomass: (1) In ecology, organic material that makes up living organisms; the collective mass of living matter in a given place and time. (2) In energy, organic material derived from living or recently living organisms, containing chemical energy that originated with photosynthesis. o Food Webs Show Feeding Relationships and Energy Flow Food chain: A linear series of feeding relationships. As organisms feed on one another, energy is transferred from lower to higher trophic levels. Compare food web. Food web: A visual representation of feeding interactions within an ecological community that shows an array of relationships between organisms at different trophic levels. Compare food chain. o Some Organisms play Outsized Roles Keystone species: A species that has an especially far-reaching effect on a community. Trophic cascade: A series of changes in the population sizes of organisms at different trophic levels in a food chain, occurring when predators at high trophic levels indirectly promote populations of organisms at low trophic levels by keeping species at intermediate trophic levels in check. Trophic cascades may become apparent when a top predator is eliminated from a system. o Communities Respond to Disturbance in Various Ways Disturbances: An event that affects environmental conditions rapidly and drastically, resulting in changes to the community and ecosystem. Disturbance can be natural or can be caused by people Resistance: The ability of an ecological community to remain stable in the presence of a disturbance. Compare resilience. Resilience: The ability of an ecological community to change in response to disturbance but later return to its original state. Compare resistance. o Succession Follows Severe Disturbance Succession: A stereotypical series of changes in the composition and structure of an ecological community through time. See primary succession; secondary succession. Primary Succession: A stereotypical series of changes as an ecological community develops over time, beginning with a lifeless substrate. In terrestrial systems, primary succession begins when a bare expanse of rock, sand, or sediment becomes newly exposed to the atmosphere and pioneer species arrive. Compare secondary succession. Secondary succession: A stereotypical series of changes as an ecological community develops over time, beginning when some event disrupts or dramatically alters an existing community. Compare primary succession Pioneer species: A species that arrives earliest, beginning the ecological process of succession in a terrestrial or aquatic community. o Communities may undergo shifts Phase shift/ regime shift: A fundamental shift in the overall character of an ecological community, generally occurring after some extreme disturbance, and after which the community may not return to its original state. Also known as a regime shift. Novel communities/ no-analog communities: An ecological community composed of a novel mixture of organisms, with no current analog or historical precedent. o Invasive Species Pose Threats to Communities Stability Introduced species: Species introduced by human beings from one place to another (whether intentionally or by accident). A minority of introduced species may become invasive species. Invasive species: A species that spreads widely and rapidly becomes dominant in a community, interfering with the community's normal functioning. o We Can Respond to Invasive Species with Control, Eradication, or Prevention o Altered Communities can be Restored Restoration ecology: The study of the historical conditions of ecological communities as they existed before humans altered them. Principles of restoration ecology are applied in the practice of ecological restoration. Ecological restoration: Efforts to reverse the effects of human disruption of ecological systems and to restore communities to their condition before the disruption. The practice that applies principles of restoration ecology. • Earth's Biomes Biomes: A major regional complex of similar plant communities; a large ecological unit defined by its dominant plant type and vegetation structure. o Climate helps determine biomes Climate diagrams/climatographs: A visual representation of a region's average monthly temperature and precipitation. Also known as a climatograph. o Aquatic and Coastal Systems Resemble Biomes o We can Divide the World into 10 Terrestrial Biomes Temperate Deciduous Forest: A biome consisting of midlatitude forests characterized by broad-leafed trees that lose their leaves each fall and remain dormant during winter. These forests occur in areas where precipitation is spread relatively evenly throughout the year. Temperate Grasslands: A biome whose vegetation is dominated by grasses and features more extreme temperature differences between winter and summer and less precipitation than temperate deciduous forests. Also known as steppe, prairie. Temperate Rainforest: A biome consisting of tall coniferous trees, cooler and less species-rich than tropical rainforest and milder and wetter than temperate deciduous forest. Tropical Rainforest: A biome characterized by year-round rain and uniformly warm temperatures. Tropical rainforests have dark, damp interiors; lush vegetation; and highly diverse biotic communities. Tropical Dry Forest/Tropical Deciduous Forest: A biome that consists of deciduous trees and occurs at tropical and subtropical latitudes where wet and dry seasons each span about half the year. Also known as tropical deciduous forest. Savanna: A biome characterized by grassland interspersed with clusters of acacias and other trees in dry tropical regions. Desert: The driest biome on Earth, with annual precipitation of less than 25 cm. Because deserts have relatively little vegetation to insulate them from temperature extremes, sunlight readily heats them in the daytime, but daytime heat is quickly lost at night, so temperatures vary widely. Tundra: A biome that is nearly as dry as desert but is located at very high latitudes. Extremely cold winters with little daylight and moderately cool summers with lengthy days characterize this landscape of lichens and low, scrubby vegetation. Boreal Forest/Taiga: A biome of northern coniferous forest. Also known as taiga, boreal forest consists of a limited number of species of evergreen trees, such as black spruce, that dominate large regions of forests interspersed with occasional bogs and lakes. Chaparral: A biome consisting mostly of densely thicketed evergreen shrubs occurring in limited small patches. Its "Mediterranean" climate of mild, wet winters and warm, dry summers is induced by oceanic influences.