ESSENTIAL KNOWLEDGE

Review: Ecosystems

 Introduction to Ecosystems 

1. In a predator-prey relationship, the predator is an organism that eats another organism (the prey).

2. Symbiosis is a close and long-term interaction between two species in an ecosystem. Types of symbiosis include mutualism, commensalism, and parasitism.

3. Competition can occur within or between species in an ecosystem where there are limited resources.

4. Resource partitioning- using the resources in different ways, places, or at different times- can reduce the negative impact of competition on survival

Food Webs and Food Chains

1. A food web is a model that depicts the flow of energy and nutrients in two or more food chains.

2. Positive and negative feedback loops can each play a role in food webs. When one species is removed from or added to a specific food web, the rest of the food web can be affected. 

Trophic Levels (feeding levels)

1. All ecosystems depend on a continuous inflow of high-quality energy in order to maintain their structure and function of transferring matter between the environment and organisms

2. In terrestrial and near-surface marine communities, energy flows from the sun to producers in the lowest trophic levels and then upward to higher trophic levels.

Primary Productivity

1. Primary productivity is the rate at which solar energy (sunlight) is converted into organic compounds via photosynthesis over a unit of time.

2. Gross primary productivity (GPP) is the total rate of photosynthesis in a given area

3. Net primary productivity (NPP)  is the rate of energy storage by photosynthesizers in a given area, after subtracting the energy lost to respiration.

4. Productivity (P)  is measured in units of energy per unit per unit time

5. Usually plants absorb red & blue light & reflect green. In the ocean, red light is absorbed in the upper 1m of water, and blue light only penetrates 100m in the clearest water. Photosynthesizers have adapted to be able to use blue & green light instead.

Energy Flow and the 10% Rule

1. The 10% rule approximates that in transfer of energy from one trophic level to the next, only about 10% of the energy is passed on.

2. The loss of energy that occurs when energy moves from lower to higher trophic levels can be explained through the laws of thermodynamics (total energy stays the same, but some usable energy is converted into heat)

The Carbon Cycle

1. The carbon cycle is the movement of molecules containing carbon between sources & sinks. Sinks are places where carbon gets stored. Main sinks are the atmosphere, living things, the ocean, sediment, & fossil fuels.

2. Some of the reservoirs in which carbon compounds occur in the carbon cycle hold those compounds for long periods of time (have fossil carbon), while some hold them for short periods of time (have modern carbon). 

3. Carbon cycles between photosynthesis and cellular respiration in living things

4. Decomposition releases CO₂. The burial of organic life stores carbon for millions of years in sediment & fossil fuels. 

5. The burning of fossil fuels quickly moves that stored carbon into atmospheric carbon, in the form of carbon dioxide.

The Nitrogen Cycle

1. The atmosphere is the major reservoir of nitrogen. Most of the nitrogen reservoirs hold those compounds for relatively short periods of time.

2. Nitrogen fixation is the process in which atmospheric nitrogen (N₂) is converted by bacteria into a form of nitrogen usable by plants (primarily ammonia NH₃ ). Plants assimilate (use) nitrogen to build their tissues

The Phosphorus Cycle

1. The phosphorus cycle is the movement of  molecules containing phosphorus between sources and sinks.

2. The major reservoirs of phosphorus in the phosphorus cycle are rock and sediments that contain hundreds of different phosphorus-bearing minerals. Minerals are natural inorganic compounds with a crystal structure

3. Most P is in rocks & there is no atmospheric form of phosphorus which makes phosphorus a limiting growth factor in aquatic and many terrestrial ecosystems

The Hydrologic (Water) Cycle

1. The hydrologic cycle, powered by the sun, is the movement of water in solid, liquid, and gaseous forms between sources and sinks.

2. The oceans are the primary reservoir of water at the Earth’s surface, with ice caps and groundwater acting as much smaller reservoirs.

Terrestrial Biomes

1. A biome contains characteristic communities of plants and animals that result from, and are adapted to, its climate.

2. Major terrestrial biomes include taiga, temperate rainforests, temperate deciduous forests, tropical rainforests, shrubland, temperate grassland, savanna, desert, and tundra

3. The global distribution of nonmineral terrestrial natural resources, such as water and trees for lumber, varies because of some combination of climate, geography, latitude and altitude, nutrient availability, and soil.

Aquatic Biomes

1. Freshwater biomes include streams, rivers, ponds, and lakes. These freshwater biomes are a vital resource for drinking water.

2. Marine biomes include oceans, coral reefs, marshland, and estuaries, Algae in marine biomes supply a large portion of the Earth’s oxygen, and also take in carbon dioxide from the atmosphere

3. The global distribution of nonmineral marine natural resources, such as different types of fish, varies because of some combination of salinity, depth, turbidity (murkiness), nutrient availability and temperature.

Review:  Biodiversity

Intro to Biodiversity

1. Biodiversity in an ecosystem includes genetic, species, and habitat diversity.

2. The more genetically diverse a population is, the better it can respond to environmental stressors. A population bottleneck can lead to loss of genetic diversity

3. Ecosystems that have a larger # of species are more likely to recover from disruptions 

4. Loss of habitat leads to a loss of specialist species, followed by a loss of generalist species. It also leads to reduced numbers of species that have large territorial requirements.

5. Species richness refers to the number of different species found in an ecosystem.

Adaptations

1. Organisms adapt to their environment over time,  in both short- and long term scales, via incremental changes at the genetic level.

2. Environmental changes, either sudden or gradual, may threaten a species’ survival, requiring individuals to alter behaviors, move, or perish.

Generalist & Specialist Species 

1. Specialist species tend to be advantaged in habitats that remain constant, while generalist species tend to be advantaged in habitats that are changing.

Island Biogeography

1. Island biogeography is the study of the ecological relationships and distribution of organisms on islands, and of these organisms’ community structures. 

2. Islands have been colonized in the past by new species arriving from elsewhere.

3. Many island species have evolved to be specialists versus generalists because of the limited resources, such as food and territory, on most islands. The long-term survival of specialists may be jeopardized if and when invasive species, typically generalists, are introduced and outcompete specialists.

K- and r- Selected Species 

1. K-selected species tend to be large, have few offspring per reproduction event, live in stable environments, expend significant energy for each offspring, mature after many years of extended youth and parental care, have long life spans/life expectancy, and reproduce more than once in their lifetime. Competition for resources in K-selected species’ habitats is usually relatively high.

2. r-selected species tend to be small, have many offspring, expend or invest minimal energy for each offspring, mature early, have short life spans, and may reproduce only once in their lifetime. Competition for resources in r-selected species’ habitats is typically relatively low.

3. Many species have reproductive strategies that are not uniquely r-selected or K-selected, or they change in different conditions at different times.

4. Biotic potential refers to the maximum reproductive rate of a population in ideal condition

5. K-selected species are typically more adversely affected by invasive species than r-selected species, which are minimally affected by invasive species. Most invasive species are r-selected species.

Ecological Tolerance 

1. Ecological tolerance refers to the range of conditions, such as temperature, salinity, flow rate, and sunlight that an organism can endure before injury or death results. 

2. Ecological tolerance can apply to individuals and to species.

Ecosystem Services

1. There are four categories of ecosystem services: provisioning, regulating, cultural, and supporting.

2. Anthropogenic activities can disrupt ecosystem services, potentially resulting in economic and ecological consequences.

Natural Disruptions to Ecosystems

1. Natural disruptions to ecosystems have environmental consequences that may, for a given occurrence, be as great as, or greater than, many human-made disruptions.

2. Earth Systems processes operate on a range of time scales. Processes can be periodic, episodic, or random.A periodic phenomenon repeats itself at regular, predictable intervals (like the 5 Ice Ages). Episodic phenomenons are infrequent & unexpected Ex: warming & seismic activity (earthquake). Random changes have no pattern. Most occurrences are NOT random 

3. Earth’s climate has changed over geological time for many reasons. For example changes in CO2, the sun’s strength, Earth’s orbit, volcanic activity, Earth’s axis, vegetation coverage, & ocean currents.

4. Sea level has varied as a result of changes in the amount of glacial ice on Earth over geological time. 

5. Major environmental change or upheaval commonly results in large swathes of habitat changes.

6. Wildlife engages in both short- and long- term migration for a variety of reasons, including natural disruptions.

Ecological Succession

1. Succession is the gradual change of species diversity, usually after a disturbance. Disturbed ecosystems will have a lower total biomass, species richness, and net productivity over time. 

2. There are two main types of ecological succession: primary and secondary succession. Primary: soil is made by mosses/lichens eroding rock. Takes a long time! Secondary: soil already exists and the climax community (ex) a rich  forest) is reached sooner

3. A keystone species in an ecosystem is a species whose activities have a particularly significant role in determining community structure & resilience

4. An indicator species is a plant or animal that, by its presence, abundance, or scarcity, indicates certain characteristics or qualities of an ecosystem

5. Pioneer species are usually the first species to move into an unoccupied habitat during succession. They’re typically mosses, lichens, bacteria, fungi, & perhaps weeds. Over time they adapt to particular conditions, which may result in a new species over time.

Review: Populations

Ecological Footprints

1. Ecological footprints compare resource demands and waste production required for an individual or a society

Introduction to Sustainability

1. Sustainability refers to humans living on Earth and their use of resources without depletion of the resources for future generations. 

2. Environmental indicators that can guide humans to sustainability include biological diversity, food production, average global surface temperatures and CO₂ concentrations, human population and resource depletion.

3. Sustainable yield is the amount of a renewable resource that can be taken without reducing available supply.

Carrying Capacity

1. When a population exceeds its carrying capacity (carrying capacity can be denoted as K), overshoot occurs. There are environmental impacts of population overshoot, including resource depletion

2. A major ecological effect of population overshoot is dieback of the population (often severe to catastrophic) because the lack of available resources leads to famine, disease, and/or conflict. 

Population Growth and Resource Availability

1. Population growth is limited by environmental factors, especially by the available resources & space.

2. Resource availability and the total resource base are limited and finite over all scales of time.

3. When the resources needed by a population for growth are abundant, population growth usually accelerates.

4. When the resource base of a population shrinks, the increased potential for unequal distribution of resources will ultimately result in increased mortality, decreased reproduction, or both, resulting in population growth declining to, or below, carrying capacity. 

Survivorship Curves

1. A survivorship curve line that displays the relative survival rates of a cohort-a group of individuals of the same age-in a population, from birth to the maximum age reached by any one cohort member. There are Type I, Type II, and Type III curves.

2. Survivorship curves differ for K-selected and r-selected species, with K-selected species typically following a Type I or Type II curve and r-selected species following a Type III curve.

Age Structure Diagrams

1. Population growth rates can be interpreted from age structure diagrams by the shape of the structure

2. A rapidly growing population will, as a rule, have a higher proportion of younger people compared to stable or declining populations.

Pre Industrial: slow growth    Transitional: rapid growth Industrial: growth rate decreases    Post-industrial: zero/negative growth

High death rates     advances in medicine           womens’ rights & family planning     advanced society, low birth rate

Total Fertility Rate

1. Total Fertility Rate (TFR) is affected by the age at which females have their first child, educational opportunities for females, access to family planning, and government acts and policies.

2. If fertility rate is at replacement levels, a population is considered relatively stable.

3. Factors associated with the infant mortality rates include whether mothers have access to good healthcare and nutrition. Changes in these factors can lead to changes in infant mortality rates over time.

Human Population Dynamics

1. Birth rates, infant mortality rates, and overall death rates, access to family planning, access to good nutrition, access to education, and postponement of marriage all affect whether a human population is growing or declining.

2. Factors limiting global human population include the Earth’s carrying capacity and the basic factors that limit human population growth (food, shelter, etc)

3. Population growth can be affected by both density-independent factors, such as major storms, fires, heat waves, or droughts, and density-dependent factors, such as access to clean water and air, food availability, disease transmission, or territory size.

4. The rule of 70 states that dividing the number 70 by the percentage population growth rate approximates the population’s doubling time. Ex)  70 / 2% = 35 years

Demographic Transition

1. The demographic transition refers to the transition from high to lower birth and death rates in a country or region as development occurs and that country moves from a preindustrial to an industrial stage The transition is typically demonstrated through a four-stage demographic transition model.

2. Characteristics of developing countries include higher infant mortality rates and more children in the workforce than developed countries.

Review: Earth Systems

Plate Tectonics 

1. Plate tectonics is a scientific theory describing the large-scale motion of seven large plates and a larger number of smaller plates of the Earth's lithosphere

   1. Lithosphere: solid layer of the earth that includes the outer crust and soil portion of the mantle. 

2. Convergent boundaries - when two plates collide. It can result in the creation of mountains, island arcs, earthquakes, and volcanoes.  

   1. Mountains: 2 continental (land) plates collide.        

   2. Island arcs: 2 oceanic plates collide, the heavier one subducts (goes under) the other lighter plate, and melts forming magma. If a volcano forms, volcanoes along boundary create a chain of islands. 

   3. Earthquakes: occurs when plates collide, pressure builds up, & energy is released

   4. Volcanoes: form when plates collide and one plate melts as it subducts (goes under) the other plate. This is what forms the RIng of Fire in the Pacific Ocean (bunch of volcanoes!)

3. Divergent boundaries can result in seafloor spreading, rift valleys, volcanoes and earthquakes.

1. Seafloor spreading: as oceanic plates move away from one another, magma emerges & new crust is formed. An underwater rift valley forms

2. Rift valley: a lowland region that forms where Earth's tectonic plates move apart, or rift. Found on land & in ocean (sea floor spreading)

3. Earthquakes at divergent plate boundaries occur as new crust is created and other crust is pushed apart & cracked

4. Volcanoes can form along plate boundary as plates separate

4. Transform boundaries  are formed when 2 plates are sliding past one another. An earthquake occurs when stress overcomes a locked up fault (boundary), releasing stored energy

5. Maps that show the global distribution of plate boundaries can be used to determine the location of volcanoes, island arcs, earthquakes, hot spots (magma close to surface), and faults (plate boundaries).

Soil Formation and Erosion

1. Soils are formed when parent material is weathered(broken down) & eroded (moved).Organic material decomposes & adds nutrients

2. Soils are generally categorized by horizons (layers) based on their composition and organic material

3. Soils can be eroded by winds or water. Protecting soils can protect water quality as soils effectively filter and clean water that moves through them.

Soil Composition and Properties

1. Water holding capacity - the total amount of water soil can hold --varies with different soil types. Water retention contributes to land productivity and fertility of soils.

2. The particle size & composition of each soil horizon can affect the porosity, permeability, and fertility of the soil

3. There are a variety of methods to test the chemical, physical, and biological properties of soil that can aid in a variety of decisions, such as irrigation and fertilizer requirements.

   1. Irrigation needs: can test moisture & permeability of water

   2. Fertilizer needs: can test for presence of nitrates & phosphates

4. A soil texture triangle is a diagram that allows for the identification and comparison of soil types based on their percentage of clay, silt, and sand.

Watersheds

1. Watershed: A watershed is an area of land that drains all the streams and precipitation to a common outlet such as a larger river, lake, wetlands, or ocean

2. Characteristics of a given watershed include its area, length, slope, soil, vegetation amount & types, and divides with adjacent watersheds.

Earth’s Geography and Climate

1. Weather and climate are affected not only by factors like the sun’s energy & latitude, but by geologic and geographic factors, such as mountains and ocean temperature.  

2. Ex) A rain shadow is a region of land that has become drier because a higher elevation area blocks precipitation from reaching the land.

Earth’s Atmosphere

1. The atmosphere is made up of major gases, each with its own relative abundance.

2. The layers of the atmosphere are based on temperature gradients and include the troposphere, stratosphere, mesosphere, thermosphere, and exosphere.

Solar Radiation & Seasons

1. Incoming solar radiation (insolation) is the Earth’s main source of energy and is dependent on season and latitude.

2. The angle of the sun’s rays determines the intensity of the solar radiation. Due to the shape of the Earth, the latitude that is directly horizontal to the solar radiation receives the most intensity. 

3. The highest solar radiation per unit area is received at the equator and decreases toward the poles.

4. The tilt of Earth’s axis of rotation causes the Earth’s seasons and the number of hours of daylight in a particular location on the Earth’s surface.

5. The solar radiation received at a location on the Earth’s surface varies seasonally, with the most radiation received during the location’s longest summer day and the least on the shortest winter day.

Global Wind Patterns

1. Global wind patterns primarily result from the most intense solar radiation arriving at the equator, resulting in density differences and Coriolis effect. 

   1. Coriolis effect: because the earth is spinning, although winds are traveling in a straight line, they seem to deflect or change direction. From their origin, wind deflects to the right in the N hemisphere & to the L in the S hemisphere

   2. Wind belts are named after the origin of the wind 

2. The N or S direction of wind is determined by convection cells, or patterns of warm air rising & cool air sinking. Picture shows how they form.

There are three main convection cells

Hadley cell: 0- 30 degrees N & S

Ferrell cell: 30-60 degrees N & S

Polar cell: 60-90 degrees N & S

El Niño and La Niña

1. El Niño and La Niña are phenomena associated with changing ocean surface temperatures in the Pacific Ocean. These phenomena can cause global changes to rainfall, wind, and ocean circulation patterns.

2. El Niño and La Niña are influenced by geological and geographic factors and can affect different locations in different ways.

NEUTRAL (normal) CONDITIONS. Normally, the winds flow from East to West, and push the warm water from South America over to the other side of the Pacific towards Australia.  This brings Australia its rain (warm water creates precipitation). The water off the coast of S.America is cool. As the warm surface water leaves off the coast of S. America, it is replaced with cold, nutrient rich water from the deep.  This is called upwelling.  Upwellings support a large variety of organisms.  The nutrients bring in a lot of small fish, which leads to a lot of food for the big fish…you get the idea.

LA NINA: Let’s make this easy.  La nina is an EXTREME version of normal conditions.  The trade winds moving from east to west speed up, pushing warm water even further away from the Pacific & the Americas and more towards Australia & the Atlantiic. The Pacific experiences unusually COOL surface water temperatures along Americas’ coasts which makes for larger than usual upwellings. Hurricane activity in the Pacific declines these years since its cooler, but it increases in the Atlantic since it has unusually WARMER temps.

EL NINO: Every few years the East to West trade winds in the tropics weaken or sometimes reverse direction.  When this happens it is called an El Nino pattern. During an El Nino pattern when the winds weaken or reverse, warm water is pushed towards the western coasts of the Americas (instead of away) and causes the surface water to heat up there. SInce warm water is moving towards our coasts, cool water is unable to rise along Americas’ western coasts resulting in less food for predators AND fisherman too. Austria experiences drought & fires. Weather around the entrep planet is affected!

Review: Land and Water Use

Tragedy of the Commons

1. The tragedy of the commons suggests that individuals will use shared resources in their own self-interest rather than in keeping with the common good, thereby depleting the resource.

The Green Revolution

1. The Green Revolution started a shift to new agricultural strategies and practices in order to produce food production, with both positive and negative results. Some of these strategies and methods are mechanization, genetically modified organisms, fertilization, irrigation, and the use of pesticides. 

2. Mechanization of farming can increase profits and efficiency for farms. It can also increase reliance on fossil fuels.

Impacts of Agricultural Practices

1. Agricultural practices that can cause environmental damage include tilling, slash-and-burn farming, irrigation, and the use of fertilizers.

Irrigation Methods

1. The largest human use of freshwater is for irrigation (70%).

2. Waterlogging occurs when too much water is left to sit in the soil, which raises the water table of groundwater and inhibits plants’ ability to absorb oxygen through their roots.

3. Salinization occurs when the salts in groundwater remain in the soil after the water evaporates. Over time, salinization can make soil toxic to plants.

4. Aquifers can be severely depleted if overused for agricultural purposes, as has happened to the Ogallala Aquifer in the central United States.

5. Types of irrigation include drip irrigation, flood irrigation, furrow irrigation, and spray irrigation. 

6. Furrow irrigation involves cutting furrows between crop rows and filling them with water. This system is inexpensive but about ⅓ of the water is lost to evaporation and runoff.

7. Flood irrigation involves flooding an agricultural field with water. This system sees about 20% of the water lost to evaporation and runoff. This can also lead to waterlogging.

8. Spray irrigation involves pumping groundwater into spray nozzles across an agricultural field. This system is more efficient than flood and furrow, with only ¼ or less of the water lost to evaporation or runoff. However, spray systems are more expensive than flood and furrow irrigation, and also require energy to run.

9. Drip irrigation uses perforated hoses to release small amounts of water to plant roots. This system is the most , with only about 5% of the water lost to evaporation and runoff. However, this system is expensive and so is not often used.

Pest Control Methods

1. One consequence of using common pest-control methods such as pesticides (herbicides, fungicides, rodenticides, and insecticides) is that organisms like weeds can become resistant to them through artificial selection. Pest control decreases crop damage by pests and increases crop yields.

   1. Evolution happens via artificial selection when pesticide survivors pass on their resistance gene to their offspring until the population is immune

2. Crops can be genetically engineered to increase their resistance to pests and disease. However, using genetically modified crops in planting or other ways can lead to loss of genetic diversity of that particular crop.

Meat Production Methods

1. Meat production is less efficient than agriculture; it takes approximately 20 times more land to produce the same amount of calories from meat as from plants.

2. Methods of meat production include concentrated animal feeding operations (CAFOs), also called feedlots, and free range grazing.

3. CAFOs are used as a way to quickly get livestock ready for slaughter. Cons: They tend to be crowded, and animals are fed grains or feed that are not as suitable as grass. Additionally, feedlots generate a large amount of organic waste, which can contaminate ground and surface water.Pros: The use of feedlots are less expensive than other methods, which can keep costs to consumers down.  

4. Free range grazing Pros: allows animals to graze on grass during their entire lifecycle. Meat from free range animals tends to be free from antibiotics and other chemicals used in feedlots. Organic waste from these animals acts as fertilizer. Cons: Free range grazing requires large areas of land and the meat produced is more expensive for consumers.

5. Overgrazing occurs when two many animals feed on a particular area of land. Overgrazing causes loss of vegetation, which leads to soil erosion.

6. Overgrazing can cause desertification. Desertification is the degradation of low precipitation regions toward being increasingly arid (dry) until they become deserts.

7. Less consumption of meat could reduce CO₂, CH₄, and N₂O emissions, conserve water, reduce the use of antibiotics and growth hormones, and improve topsoil.

Impacts of Overfishing

1. a.Overfishing has led to the extreme scarcity of some fish species, which can lessen biodiversity in aquatic systems and harm people who depend on fishing for food and commerce.

b. Solutions to overfishing include aquaculture (fish farming), setting fishing limits, & prohibiting fishing in certain areas (near reefs or where fish reproduce)

Integrated Pest Management

1. Integrated Pest Management (IPM) is a combination of methods used to effectively control pest species while minimizing the disruption to the environment. These methods include biological, physical, and limited chemical methods such as natural predators (biocontrol), intercropping,& crop rotation. 

2. The use of IPM reduces the risk that pesticides pose to wildlife, water supplies, and human health.

3. IPM minimizes disruptions to the environment and threats to human health but can be complex and expensive.

Sustainable Agriculture

1. The goal of soil conservation is to prevent soil erosion. Different methods of soil conservation include contour plowing, windbreaks, perennial crops (come up every year), terracing, no-till agriculture, and strip cropping.

2. Strategies to improve soil fertility include crop rotation and the addition of green manure and limestone.

   • Limestone balances acidic soils, improving soil bacteria and plant health

3.  Rotational grazing is the regular rotation of livestock between different pastures in order to avoid overgrazing in a particular area. 

Aquaculture

1. Aquaculture has expanded because it is highly efficient, requires only small areas of water, and requires little fuel.

2. Aquaculture can contaminate wastewater, and fish that escape can compete or breed with wild fish. The density of fish in aquaculture can lead to increases in disease incidences, which can be transmitted to wild species.

Sustainable Forestry

1. Some of the methods for mitigating deforestation include reforestation, using and buying wood harvested by ecologically sustainable forestry techniques, and reusing wood.

2. Methods to protect forests from pathogens and insects include IPM and the removal of affected trees.

3.  Prescribed burn is a method by which forests are set on fire under controlled conditions in order to reduce the occurrence of natural fires.

Clearcutting

1. Clearcutting can be economically advantageous but leads to soil erosion, increased soil and water temperatures (loss of shade), and flooding.

2. Forests contain trees that absorb pollutants and store carbon dioxide. The cutting and burning of trees releases carbon dioxide and contributes to climate change.

Review: Energy Resources and Consumption

Renewable and Nonrenewable Resources

1. Nonrenewable energy sources are those that exist in a fixed amount and involve energy transformation that cannot be easily replaced.

2. Renewable energy sources are those that can be replenished naturally, at or near the rate of consumption, and reused.

Global Energy Consumption

1. The use of energy resources is not evenly distributed between developed and developing countries.

2. The most widely used sources of energy globally are fossil fuels.

3. As developing countries become more developed, their reliance on fossil fuels for energy increases.

4. As the world becomes more industrialized, the demand for energy increases.

5. Availability, price, & governmental regulations influence which energy sources people use and how 

Fuel Types and Uses

1. Wood is commonly used as fuel in the forms of firewood and charcoal. It is often used in developing countries because it is easily accessible. 

   1. Wood can be converted into charcoal by burning in low oxygen conditions

2. Peat is partially decomposed organic material that can be burned for fuel.

3. Three types of coal used for fuel are lignite, bituminous, and anthracite. Heat, pressure, and depth of burial contribute to the development of various coal types and their qualities

4. Natural gas, the cleanest of the fossil fuels, is mostly methane.

5. Crude oil can be recovered from tar sands, which are a combination of clay, sand, water, and bitumen (a black, sticky substance such as tar or asphalt).

6. Fossil fuels can be made into specific fuel types for specialized uses (ex - gas, diesel, kerosene, etc)

7. Cogeneration occurs when a fuel source is used to generate both useful heat and electricity; utilization of the steam left over from electricity generation to produce heat.

Distribution of Energy Resources

1. The global distribution of natural energy resources, such as ores, coal, crude oil, and gas, is not uniform and depends on regions’ geologic history

Fossil Fuels 

1. The combustion of fossil fuels is a chemical reaction between the fuel and oxygen that yields carbon dioxide and water and releases energy. 

2. Energy from fossil fuels is produced by burning those fuels to generate heat, which then turns water into steam. That steam turns a turbine, which generates electricity.

3. Humans use a variety of methods to extract fossil fuels from the earth for energy generation.

4. Hydraulic fracturing (fracking) can cause groundwater contamination and the release of volatile organic compounds.

Nuclear Power 

Nuclear power is generated through fission, where atoms of uranium-235, which are stored in fuel rods, are split into smaller parts after being struck by a neutron. Nuclear fission releases a large amount of heat, which can be used to generate steam, which powers a turbine and generates electricity.

1. Radioactivity occurs when the nucleus of a radioactive isotope loses energy by emitting radiation.

2. Uranium-235 remains radioactive for a long time, which leads to problems associated with the disposal of nuclear waste.

3. Nuclear power generation is a nonrenewable energy source. Nuclear power is considered a cleaner energy source because it does not produce air pollutants, but it does release thermal pollution and hazardous solid waste.

4. Three Mile Island, Chernobyl, and Fukushima are three cases where accidents or natural disasters led to the release of radiation. These releases have had short- and long-term impacts on the environment.

5. A radioactive element’s half-life can be used to calculate a variety of things, including the rate of decay and the radioactivity level at specific points in time.

Energy from Biomass

1. Burning of biomass produces heat for energy at a relatively low cost, but it also produces carbon dioxide, carbon monoxide, nitrogen oxides, particulates, and volatile organic compounds. The overharvesting of trees also causes deforestation.

2. Ethanol can be used as a substitute for gasoline. Burning ethanol does not introduce additional carbon into the atmosphere via combustion, but the energy return on energy investment for ethanol is low.

Solar Energy

1. Photovoltaic solar cells capture light energy from the sun and transform it directly into electrical energy. Their use is limited by the availability of sunlight.

2. Active solar energy systems use solar energy to hear a liquid through mechanical and electrical equipment to collect and store the energy captured from the sun.

3. Passive solar energy systems absorb heat directly from the sun but without the use of mechanical and electric equipment, and energy cannot be collected or stored.

4. Solar energy systems have low environmental impact and produce clean energy, but they can be expensive. Large solar energy farms may negatively impact desert ecosystems.

Hydroelectric Power

1. Hydroelectric power can be generated in several ways. Dams built across rivers collect water in reservoirs. The moving water can be used to spin a turbine. Turbines can also be placed in small rivers, where the flowing water spins a turbine. 

2. Tidal energy uses the energy produced by tidal flows to turn a turbine.

3. Hydroelectric power does not generate air pollution or waste, but construction of the power plant can be expensive, and there may be a loss of or a change in habitats following the construction of dams.

Geothermal Energy

1. Geothermal energy is obtained by using the heat store in the Earth’s interior to heat up water, which is brought back to the surface as steam. The steam is used to drive an electric generator.

2. The cost of accessing geothermal energy can be prohibitively expensive, as it is not easily accessible in many parts of the world. In addition, it can cause the release of hydrogen sulfide.

Hydrogen Fuel Cell

1. Hydrogen fuel cells are an alternate to non-renewable fuel sources. They use hydrogen as fuel, combining the hydrogen and oxygen in the air to form water and release energy (electricity) in the process. Water is the product (emission) of a fuel cell.

2. Hydrogen fuel cells have low environmental impact and produce no carbon dioxide when the hydrogen is produced from water. However, the technology is expensive, and energy is still needed to create the hydrogen gas when used in the fuel cell.

Wind Energy

1. Wind turbines use the kinetic energy of moving air to spin a turbine, which in turn converts the mechanical energy of the turbine into electricity.

2. Wind energy is a renewable, clean source of energy. However, birds and bats may be killed if they fly into the spinning turbine blades.

Energy Conservation

1. Some of the methods for conserving energy around a home include adjusting the thermostat to reduce the use of heat and air conditioning, conserving water, use of energy-efficient appliances, and conservation landscaping.

2. Methods for conserving energy on a large scale include improving fuel economy for vehicles, using battery electric vehicles and hybrid vehicles, using public transportation, and implementing green building design features.

Review: Air Pollution

Indoor Air Pollutants

1. Carbon monoxide is an indoor air pollutant that is classified as an asphyxiant (suffocates)

2. Indoor air pollutants that are classified as particulates include asbestos, dust and smoke.

3. Indoor air pollutants can come from natural sources, human-made sources, and combustion. Common natural sources of indoor air pollutants include radon, mold, and dust.

4. Common human-made indoor air pollutants include insulation, VOCs, from furniture, paneling, and carpets; formaldehyde from building materials, furniture, upholstery, and carpeting; & lead from paints.

5. Common combustion air pollutants include carbon monoxide (CO), nitrogen oxides (NOx), sulfur oxides (SOx), particulates, and tobacco smoke.

6. Radon-222 is a naturally occurring radioactive gas that is produced by the decay of uranium found in some rocks and soils. 

7. Radon gas can infiltrate homes as it moves up through the soil and enters homes via the basement or cracks in the walls of foundation. It is also dissolved in groundwater that enters homes through a well.

8. Exposure to radon gas can lead to radon-induced lung cancer, which is the leading cause of lung cancer in America.

Introduction to Outdoor Air Pollution

1. Coal combustion releases air pollutants including carbon dioxide, sulfur dioxide, toxic heavy metals, and particulates.

2. The combustion of fossil fuels releases nitrogen oxides into the atmosphere. They lead to the production of ozone, formation of photochemical smog, and convert to nitric acid in the atmosphere, causing acid rain. Other pollutants produced by fossil fuel combustion include carbon monoxide, hydrocarbons, and particulate matter

MAJOR PRIMARY POLLUTANTS MAJOR SECONDARY POLLUTANTS

• Particulate matter PM

• Nitrogen oxides NOx

• Sulfur oxides SOx

• Mercury & lead

• CO₂ and CO

• Volatile Organic Compounds VOCs

• Sulfuric acid H₂SO₄

• Nitric acid HNO₃ 

• Smog   

• Ozone
  

Through the Clean Air Act, the Environmental Protection Agency regulates the emission of air pollutants that affect human health. The EPA regulated the use of lead, particularly in fuels, which dramatically decreased the amount of lead in the atmosphere

Acid Rain

3. Acid rain/deposition is due to nitrogen oxides & sulfur oxides from anthropogenic & natural sources 

4. Nitrogen oxides that cause acid deposition come from mainly motor vehicles. Sulfur dioxides that cause acid deposition come from coal-burning power plants

5. Acid deposition mainly affects communities that are downwind from coal-burning power plants.

6. Acid rain/deposition can lead to the acidification of soil & water, damage to plants, damage to man-made structures, & a decrease in biodiversity

Thermal Inversion

1. During a thermal inversion, the normal temperature gradient in the atmosphere is altered as the air temperature at the Earth’s surface is cooler than the air at higher altitudes.

2. Thermal inversion traps pollution close to the ground, especially smog and particulates.

Photochemical Smog

3. Photochemical smog is formed when nitrogen oxides and volatile organic hydrocarbons (VOCs) react with heat and sunlight to produce a variety of pollutants (like ozone)

4. Photochemical smog often forms in urban areas because of the large number of motor vehicles there. 

5. Photochemical smog can harm human health, including respiratory problems and eye irritation. 

6. Photochemical smog can be reduced through the reduction of nitrogen oxide and VOCs.

7. Volatile organic compounds, such as formaldehyde and gasoline, evaporate or sublimate at room temperature. Trees are a natural source of VOCs.

Air Pollution Solutions

1. Methods to reduce air pollutants include regulatory practices, conservation practices, and alternative fuels.

2. A catalytic converter is an air pollution control device for internal combustion engines that converts pollutants (CO, NOx, and hydrocarbons) in exhaust into less harmful molecules (CO2, N2, O2, and H2O).

3. A vapor recovery nozzle is an air pollution control device on a gasoline pump that prevents fumes from escaping into the atmosphere when fueling a motor vehicle

4. Wet and dry scrubbers are air pollution control devices that remove harmful particulates and/or gases from industrial exhaust streams.

5. Methods to reduce air pollution from coal burning power plants include scrubbers, electrostatic precipitators, & baghouse filters

Stratospheric, good ozone depletion

1. The stratospheric ozone layer is important to the evolution of life on Earth and the continued health and survival of life on Earth. It protects us from harmful ultraviolet light from the sun

2. Stratospheric ozone depletion is caused by anthropogenic factors, such as chlorofluorocarbons (CFCs), and natural factors, such as the  ice crystals forming in the atmosphere. The crystals serve as a surface for CFCs to react with ozone (recent discovery). The ozone hole forms over Antarctica. 

3. A decrease in stratospheric ozone increases the UV rays that reach the Earth’s surface. Exposure to UV rays can lead to skin cancer and cataracts in humans.

4. Ozone depletion can be mitigated by replacing ozone-depleting chemicals with substitutes that do not deplete the ozone layer. Hydrofluorocarbons (HFCs) are one such replacement, but some are strong greenhouse gases.

Noise Pollution

1. Noise pollution is sound at levels high enough to cause physiological stress & hearing loss

2. Sources of noise pollution in urban areas include transportation, construction, and domestic and industrial activity.

3. Some effects of noise pollution on animals in ecological systems include stress, the masking of sounds used to communicate or hunt, damaged hearing, and causing changes to migratory routes.

Review: Water Pollution & Human Health

Pathogens 

• It can be difficult to establish a cause and effect between pollutants and human health issues because humans experience exposure to a variety of chemicals and pollutants.

• As equatorial climates (warm with wet/dry seasons) spread north and south into what are currently subtropical and temperate climate zones, pathogens, infectious diseases, and vectors are spreading into these areas where the disease has not previously been known to occur.

• Pathogens are able to adapt, evolve, & take advantage of new opportunities to infect and spread through human populations.

• Pathogens can occur in many environments regardless of the appearance of sanitary conditions.

• Impoverished,  low-income areas often lack sanitary waste disposal and have contaminated drinking water supplies, leading to havens and opportunities for the spread of infectious disease. 

 Infectious Diseases are contagious diseases caused by a pathogen & can be spread through a vector

Sources of Pollution

• A point source refers to a single, identifiable source of a pollutant, such as a smokestack or waste discharge pipe

• Nonpoint sources of pollution are diffuse and can therefore be difficult to identify, such as pesticide spraying or urban runoff.

Human Impacts on Ecosystems

• Organisms have a range of tolerance for various pollutants. Organisms have an optimum range for each factor where they can maintain homeostasis. Outside of this range, organisms may experience physiological stress, limited growth, reduced reproduction, and in extreme cases, death.

• Coral reefs have been suffering damage due to a variety of factors, including increasing ocean temperatures, sediment runoff, and destructive fishing practices.

• Increased sediment in waterways can reduce light infiltration, which can affect primary producers and visual predators. Sediment can also clog the gills of fish or settle, disrupting habitats 

Oil pollution

• Oil spills in marine waters cause organisms to die either from suffocation, petroleum poisoning, or hindering their ability to survive.Oil that floats on the surface of the water can coat the feathers of birds and fur of marine mammals. Some components of oil sink to the ocean floor, killing some bottom-dwelling organisms. 

• Oil that washes up on the beach can have economic consequences on the fishing & tourism industries.

Nutrient pollution & Eutrophication

• The increase in nutrients in aquatic environments is called eutrophication. Anthropogenic causes of eutrophication are agricultural runoff and wastewater release.

• It can lead to an algal bloom. When the algal bloom dies, microbes digest the algae, along with the oxygen in the water, leading to a decrease in the dissolved oxygen levels in the water. The lack of dissolved oxygen can result in large die-offs of aquatic organisms

• Hypoxic waterways are those bodies of water that are low in dissolved oxygen.

• Oceanic dead zones are areas of low oxygen in the world’s oceans caused by nutrient pollution.

• An oxygen sag curve is a plot of dissolved oxygen levels versus the distance from a source of pollution. The closer to the source of pollution, the lower the oxygen concentration.

• Compared to eutrophic waterways, oligotrophic waterways have very low amounts of nutrients, stable algae populations, and high dissolved oxygen

Thermal Pollution

• Thermal pollution occurs when heat released into the water produces negative effects to the organisms in that ecosystem such as thermal shock

• Variations in water temperature affect the concentration of dissolved oxygen (DO) because warm water does not contain as much oxygen as cold water.

Bioaccumulation and Biomagnification

• Bioaccumulation is the absorption and concentration of certain elements or compounds by cells in a living organism, most commonly fat cells

• Biomagnification is the increase in concentration of substances per unit of body tissue that occurs in successively higher trophic levels of a food chain or in a food web.

  • DDT, mercury, and PCBs are persistent substances that bioaccumulate and have significant impacts.

  • Some effects that can occur in an ecosystem when a persistent substance is biomagnified in a food chain include eggshell thinning & developmental deformities in higher trophic levels.

  • Humans also experience harmful effects from biomagnification, including issues with the reproductive, nervous, and circulatory systems.

• Heavy metals can bioaccumulate in living things. Examples are mercury, lead, & arsenic. They’re neurotoxins!

  • When mercury enter aquatic environments, bacteria in the water convert it to highly toxic methylmercury

  • They’re mainly released from mining,disposal of  industrial waste, and burning of fossil fuels. 

  • Can reach the groundwater, impacting the drinking water supply.  

Types of toxins

• Heavy metals like mercury &  lead are neurotoxins - toxins that damage the nervous system

• Carcinogens are substances that can cause cancer. Examples: 

  • PCBs   - synthetic, heat resistant chemicals

  • Some pesticides

  • Dioxin - produced when burning trash or fossil fuels

  • Flame retardants- also a neurotoxin

• Endocrine disruptors are chemicals that mimic hormones & interfere with the endocrine system.

  • Endocrine disruptors can lead to birth defects & neuro-developmental disorders like a decreased IQ, poorer memory, or other behavioral problems.

Persistent Organic Pollutants (POPs)

• Persistent organic pollutants (POPs) are synthetic, carbon-based molecules that do not easily break down in the environment because. Examples include such as DDT , PCBs, & Dioxin.

• POPs can be toxic to organisms because they are soluble in fat, which allows them to accumulate in organisms’ fatty tissues.

• POPs can travel over long distances via wind and water before being redeposited.

Summary of types of toxins

Summary of toxins

Lethal Dose 50% (LD₅₀) & Dose Response Curve

• Lethal dose 50% is the dose of a chemical that is lethal to 50% of a tested population of a particular species. 

• A dose response curve describes the effect on an organism or mortality rate in a population based on the dose of a particular toxin or drug.

Solid Waste Disposal

• Solid waste is any discarded material that is not a liquid or gas. It is generated in domestic,  sanitary municipal landfill industrial, business, and agricultural sectors.

• Litter that reaches aquatic ecosystems can create intestinal blockage and choking hazards for wildlife and introduce toxic substances to the food chain

• Solid waste is most often disposed of in landfills. Landfills can contaminate groundwater and release harmful gases.

• A sanitary municipal landfill consists of a bottom liner (plastic or clay), a storm water collection system, a leachate collection system NEW: a cap, and a methane collection system

• Some countries dispose of their waste by dumping it in the ocean. This practice, along with other sources of plastic, has led to large floating islands of trash in the oceans. Additionally, wildlife can become entangled in the waste, as well as ingest it.

• Electronic waste, or e-waste, is composed of discarded electronic devices including televisions, cell phones, computers.

  •  E-wastes may contain hazardous chemicals, including heavy metals such as lead and mercury, which can leach from landfills into groundwater if they are not disposed of properly.

• Factors in landfill decomposition include the composition of the trash and conditions needed for microbial decomposition of the waste like the presence or absence of oxygen & water

• Solid waste can also be disposed of through incineration, where waste is burned at high temperatures. This method significantly reduces the volume of solid waste but releases air pollutants.

• Some items are not accepted in sanitary landfills and may be disposed of illegally, leading to environmental problems. One example is used rubber tires, which when left in piles can become breeding grounds for mosquitoes that can spread disease.

Waste Reduction Methods

• Recycling is a process by which certain solid waste materials are processed and converted into raw materials to make new products.

• Recycling is one way to reduce the current global demand on minerals, but this process is energy-intensive and can be costly.

• Composting is the process where organic matter such as food scraps, paper, and yard wastes decompose into a product that can be used as fertilizer. Drawbacks include odor and rodents.

• E-waste can be reduced by recycling and reuse.

• Incinerating waste decreases the volume of trash but the heat can also be used to make electricity

• Once the landfill has been capped (covered), the habitat can be restored into useful land like a park

• The combustion of gases like methane produced from decomposition of organic material in landfills can be used to generate electricity.

Sewage Treatment

• Primary treatment of sewage is the physical removal of large objects, often through the use of screens and grates, followed by the settling of solid waste in the bottom of a tank.

• Secondary treatment is a biological process in which bacteria break down organic matter into carbon dioxide and inorganic sludge, which settles in the bottom of a tank. The tank is aerated to increase the rate at which the bacteria break down the organic matter.

• Tertiary treatment is the use of ecological or chemical processes to remove any pollutants left in the water after primary and secondary treatment.

  • Prior to discharge, the treated water is exposed to one or more disinfectants (usually chlorine, ozone, or UV light) to kill bacteria.

Review: Global Change

The Greenhouse Effect

• The principal greenhouse gases (GHGs) are carbon dioxide, methane, water vapor, nitrous oxide, and chlorofluorocarbons (CFCs).

• While water vapor is a greenhouse gas, it doesn’t contribute significantly to global climate change because it has a short residence time in the atmosphere.

• The greenhouse effect results in the surface temperature necessary for life on Earth to exist.

• Carbon dioxide, which has a global warming potential (GWP) of 1, is used as a reference point for the comparison of different GHGs and their impacts on global climate change. CFCs have the highest GWP, followed by nitrous oxide, then methane.

Increases in the Greenhouse Gases

• Global climate change, caused by excess GHGs in the atmosphere, can lead to a variety of environmental problems including rising sea levels resulting from melting ice sheets and ocean water expansion, and disease vectors spreading from the tropics toward the poles. These problems can lead to changes in population dynamics and population movements in response.

Global Climate Change

• The Earth has undergone climate change throughout geologic time, with major shifts in global temperatures causing periods of warming and cooling as recorded with CO₂ data and ice cores.

• Effects of climate change include rising temperatures, melting permafrost and sea ice, rising sea levels, and displacement of coastal populations.

• Marine ecosystems are affected by changes in sea level, some positively, such as in newly created habitats on now-flooded continental shelves, and some negatively, such as deeper communities that may no longer be in the photic zone of seawater.

• Winds generated by atmospheric circulation help transport heat throughout the Earth. Climate change may change circulation patterns, as temperature changes may impact Hadley cells and the jet stream.

• Oceanic circulation, or ocean conveyor belt, carry heat throughout the world. When these currents change, it can have a big impact on global climate, especially in coastal change.

• Climate change can affect soil through changes in temperature and rainfall, which can impact soil’s viability and potentially increase erosion.

• Earth’s polar regions are showing faster response times to global climate change because ice and snow in these regions reflect the most energy back out to space, leading to a positive feedback loop.

• As the Earth warms, this ice and snow melts, meaning less solar energy is radiated back into space and instead is absorbed by the Earth’s surface. This in turn causes more warming of the polar regions.

• Global climate change response time in the Arctic is due to positive feedback loops involving melting sea ice and thawing tundra, and the subsequent release of GHGs like methane.

• One consequence of the loss of sea ice and snow in polar regions is the effect on species that depend on the ice for habitat and food.

Ocean Warming

• Ocean warming is caused by the increase in GHGs in the atmosphere.

• Ocean warming can affect marine species in a variety of ways, including loss of habitat, and metabolic and reproductive changes.

• Ocean warming is causing coral bleaching, which occurs when the loss of algae within corals cause the corals to bleach white. Some corals recover and some die.

Ocean Acidification

• Ocean acidification is the decrease in pH of the oceans, primarily due to increased CO₂ concentrations in the atmosphere, and can be expressed as chemical equations.

• As more CO₂ is released into the atmosphere, the oceans, which absorb a large part of that CO2, become more acidic.

• Anthropogenic activities that contribute to ocean acidification are those that lead to increased CO₂ concentrations in the atmosphere: burning of fossil fuels, vehicle emissions, and deforestation.

• Ocean acidification damages coral because acidification makes it difficult for them to form shells, due to the loss of calcium carbonate.

Invasive Species

1. Invasive species are species that can live and sometimes thrive outside of their normal habitat. They are considered invasive because they threaten native species. Invasive species are often generalist that reproduce quickly and therefore may outcompete native species for resources.

2. Invasive species can be controlled through a variety of human interventions such as physical removal and prevention through inspecing boats, shipping crates, and luggage for exotic species.

Endangered Species

1. A variety of factors can lead to a species becoming threatened with extinction, such as being extensively hunted,  being outcompeted by an invasive species, having a limited diet that is threatened, or having specific and limited habitat requirements.

2. Not all species will be in danger of extinction when exposed to the same changes in their ecosystem. Species that are able to adapt to changes in their environment (generalists & invasive species) or are able to adapt quickly or move to a new environment are less likely to face extinction. 

3. Selective pressures are any factors that change the behaviors and fitness of organisms within an environment.Types of selection pressures include:

   1. Resource availability – Presence of sufficient food, habitat (shelter/ territory) and mates

   2. Environmental conditions – Temperature, weather conditions or geographical access

   3. Biological factors – Predators and pathogens (diseases)

4. Species in a given environment compete for resources like territory, food, mates, and habitat, and this competition may lead to endangerment or extinction.

5. Strategies to protect animal populations include criminalizing poaching, protecting animal habitats, and legislation.

 Human Impacts on Biodiversity

1. HIPPCO (habitat destruction, invasive species, population growth (human), pollution, climate change, and over exploitation) describes the main factors leading to a decrease in biodiversity.

2. a. Habitat fragmentation occurs when large habitats are broken into smaller, isolated areas. This decreases biodiversity and makes habitats more prone to invasive species.

b. Causes of habitat fragmentation include the construction of roads and pipelines, clearing for agriculture or development, and logging.

c. The scale of habitat fragmentation that has an adverse effect on the inhabitants of a given ecosystem will vary from species to species within that ecosystem. Specialists will be more affected than generalists.

3. Global climate change can cause habitat loss via changes in temperature, precipitation, and sea level rise.

4. Overfishing has led to the extreme scarcity of some fish species, which can lessen biodiversity in aquatic systems and harm people who depend on fishing for food and commerce. 

5. Some organisms have been somewhat or completely domesticated and are now managed for economic returns, such as honeybee colonies and domestic livestock. This domestication can have a negative impact on the biodiversity of that organism because only certain breeds of those species will continue to be bred.

6. Some ways humans can mitigate the impact of loss of biodiversity include creating protected areas, use of habitat corridors (strips of land that connect habitats), promoting sustainable land use practices (like smart planning, maintaining vegetation, & protecting soil), and restoring lost habitats.

7. We can also create legislation like the Endangered Species Act and CITES to protect species. 

a.The Endangered Species Act prohibits the hunting or harming of species on the endangered species list & prohibits the disturbance of their habitat. 

b. CITES The Convention on International Trade in Endangered Species of Wild Fauna and Flora, often referred to as CITES (SIGH-teez), is an agreement between governments that regulates the international trade of wildlife and wildlife products—everything from live animals and plants to food, leather goods, and trinkets. It came into force in 1975 with the goal of ensuring that international trade does not threaten the survival of wild plants and animals.

Legislation

• CLEAN AIR ACT:  regulates the emission of air pollutants that affect human health. Set emission standards for cars

• CLEAN WATER ACT: Set maximum permissible amounts of water pollutants that can be discharged into waterways..aim to make surface waters swimmable and fishable

• CONVENTION ON INTERNATIONAL TRADE 

IN ENDANGERED SPECIES OF WILD FAUNA & FLORA (CITES): Lists species that cannot be commercially traded as live specimens or wildlife products. 5,950 species of animals and 32,800 species of plants are protected

• COMPREHENSIVE ENVIRONMENTAL RESPONSE, COMPENSATION, AND LIABILITY ACT (CERCLA):  aka Superfund Act - gave the EPA the power to investigate and clean up sites contaminated with hazardous substances. Superfund is funded by taxes (not from our paychecks)

• KYOTO PROTOCOL: Controlling global warming by setting greenhouse gas emissions targets for developed countries

• MONTREAL PROTOCOL: Controlling global warming by setting greenhouse gas emissions targets for developed countries

• ENDANGERED SPECIES ACT: Identifies threatened and endangered species in the US, and puts their protection ahead of economic considerations. Created 

‘Red list’ of endangered species

• SAFE DRINKING WATER ACT (SWDA): Set maximum contaminant levels for pollutants in drinking water that may have adverse effects on human health

• DELANEY CLAUSE OF FOOD, DRUG, AND COSMETIC ACT: requires the Food and Drug Administration (FDA) to ban food additives which are found to cause or induce cancer in humans or animals as indicated by testing.

• RESOURCE CONSERVATION AND RECOVERY ACT (RCRA): Controls hazardous waste with a ‘cradle-to-grave’ system. Hazardous waste is tracked from creation to disposal -  from ‘birth’ to ‘death’