Environmental Test 3

5G- Controversy around peak oil

"Optimists" -Increasing assessments of global reserves - Technology will increase production "Peakists" -• Other assessments less rosy • Reserves take 6-10 years to drill, develop, & become part of the supply • Production is still declining; technology can only slow this decline rate • Some of this technological development is uncertain TB OPTIMIST: -oil supplies dwindle, rising prices will create: - powerful incentives for busi- nesses, governments, and individuals --to conserve energy and to develop alternative energy sources and that these developments will save us from major disruptions. NEGATIVE: Supply and demand could have huge effects: -economic -social -political consequences -Lacking cheap oil with which to transport goods long distances, today's globalized economy would collapse into a large number of isolated and localized economies. -Large cities would require urban agriculture to feed their residents -fewer petroleum- based fertilizers and pesticides we could feed only a fraction of the world's 7 billion people. -The American suburbs would be hit particularly hard because of their dependence on the automobile.

Types of toxins

"Toxicants can be classified based on their particular effects on health." • Carcinogens • Mutagens • Teratogens • Neurotoxins • Allergens • Endocrine disruptors

Soil degradation - & Causes

"a deterioration of soil quality and decline in soil productivity, -resulting from -forest removal, -cropland agricultur -and overgrazing of live stock Anything that reduces plant cover leads to soil degradation -Over the past 50 years, soil degradation has reduced global grain production by 13% CAUSES -Overgrazing (34%) "occurs when livestock eliminate the vegetation that covers the soil." -Deforestation (30%) -Cropland Agriculture (28%) -Other Overexploitation (7%) -Industrialization (1%) --(We lose 5-7 million ha (12-17 million acres) of productive cropland each year!) TB "Throughout the world, especially in drier regions, it has become more difficult to raise crops and graze livestock as soils deteriorate in quality and decline in productivity" Results primarily from 1) -forest removal, 2)cropland agriculture 3) overgrazing of livestock $$Soil degradation is central to the broader problem known as land degradation. -Land degradation = deterioration of land that diminishes its - productivity and biodiversity -impairs the functioning of its ecosystems -reduces the ecosystem services it offers us. -Land degradation is caused by: --the cumulative impacts of unsustainable agriculture, --deforestation --urban development. -is manifested in processes such as: -soil erosion -nutrient depletion -water scarcity, -salinization (p. 234), -water logging (p. 234), -chemical pollution, -changes in soil structure and pH, -loss of organic matter from the soil. -It is a global phenomenon that affects up to one-third of the world's people.

Shelterbelts

(AKA windbreaks): rows of trees planted along edges of fields - Minimizes wind erosion TB -226

How scientists study effects of toxins

- Case history approach - Epidemiological studies - Manipulative experiments

Surface mining

- Strip mining - Mt top removal?

Green revolution

-Around 1950, -Introduced new technology, crop varieties, & farming practices to the developing world Positive effect: People -- Intensified agriculture saved millions from starvation --Rich farmers with lots of land benefited ("farmers with larger plots of land were best positioned to invest in Green Revolution technologies") Environment -- Prevented some deforestation and land conversion -- Preserved biodiversity and ecosystems Negative effect: People --Poor farmers were driven off the land into cities (" unable 2 afford these technologies were driven out of business and moved to cities, adding to the immense migration of poor rural people to urban areas of the developing world ") Environment --Pollution, erosion -- Salinization, desertification --Today, yields are declining in many Green Revolution areas ( "Likely due to soil degradation from the heavy use of fertilizers, pesticides, and irrigation") TB -led by desire for greater quantity and quality of food for our growing population GOAL: to enhance agricultural pro- ductivity in developing nations. (p. 247) METHOD: Scientists used selective breeding to develop crop strains that grew quickly, were more nutritious, or were resistant to disease or drought. CONSEQUENCE POSITIVE-increased efficiency of production (rice, wheat, corn, soybean) fed more people while reducing the amount of natural land converted for farming. --(intensified use of already-cultivated land reduced pressures to convert additonal natural lands for new cultivation.) NEGATIVE-expanded use of fossil fuels, chemical fertilizers, and synthetic pesticides enhanced yields but has also increased pollution and soil degradation (top soil losses and soil quality) -agricultural scientists devised methods and technologies to increase crop output per unit area of existing cultivated land. -- As a result, industrialized nations dramatically increased their per-area yields --key to ending starvation in developing nations. *Norman Borlaug* - helped launch the Green Revolution. - high-yielding, disease-resistant wheat that he bred helped boost agricultural productivity in many developing countries. -"saved more lives than anyone in history"

Extracting Fossil Fuels: oil and natural gas -Hydralic

-Drilling (conventional and unconventional) --When a target source is liquid or gas in form, drilling may be used for extraction Hydraulic fracturing (unconventional drilling) ---oil shale • Method of extracting methane (CH4) and oil from unproductive rocks • Involves digging a well, inject water, chemicals, and sand at high pressure ---gas is pumped up through pipelines, installed in man-made fractures. Fractures are produced through high-pressure injections of fluid and particulate matter BENEFITS: • When CH4 is used instead of coal, it reduces CO2 emissions • Low cost (right now, anyway) DRAWBACKS: • Uses a lot of water => supply & disposal issues ---1-7 million gallons of water are injected for fracking • Uses a lot of chemicals => groundwater contamination? ---Fracking fluid has 596 chemicals (many are carcinogenic) ----When water resurfaces from wells, it is evaporated into air, still containing chemicals • Uses a lot of sand => sand has to be mined, too • CH4 leaks/ escapes? CONTROVERSIAL -Cracks formed during fracking perforate the aquifer, allowing the solvents injected into the well, oil and natural gas to leak into the ground water Fracked water has been linked with: -Neourological problems -Chronic headaches -Chronic illness/digestive problems -Brain damage -Asthma (from evaporations of chemicals post-extraction) FACTS -wells can be tracked 18 times in life time TB HYDRAULIC FRACTURING -use when oil and gas trapped tightly in impermeable shale deposits -secondary extraction and also to tap into new deposits. INVOLVES pumping chemically treated water under high pressure into deep layers of shale to crack them. -Sand or small glass beads are inserted to hold the cracks open as the water is withdrawn. -Gas or oil then travels upward, with pressure and pumping, through the newly created system of fractures RESULTS - allows us to extract gas and oil that is so dispersed through shale formations that it cannot be pumped out by standard drilling. -by making formerly inaccessible deposits accessible, it has raised proven reserves and has ignited a boom in natural gas extraction in U.S.. -Natural gas prices have fallen, -gas usage in the United States has risen. DEBATE among people living in each area where it has occurred (FIGURE 19.14). For exam- ple, hydrofracking of the massive Marcellus Shale deposit is affecting the landscapes, economies, politics, and everyday lives of people in Pennsylvania, New York, and neighbor- ing states (see Chapter 7). The choices people face -between financial gain and impacts to their health, drinking water, and environment -natural gas rush brings jobs and money to small towns but can also spark social upheaval and leave communities with a legacy of pollution. TB Oil

Current status of agriculture

-Due to technology, food production exceeds population growth BUT: Soils, water supply, and biodiversity are in decline - Most arable land is already farmed By 2050, we will have to feed 9 billion people! TB $$$(4 now) "We are moving toward sustainable agriculture" -ppl think to sustain our population in the long run we will need to begin raising animals and crops in ways that are less polluting and less resource- intensive. Sustainable agriculture is agriculture that does not deplete soils faster than they form (p. 216). =It is farming and ranching that does not reduce the amount of healthy soil, clean water, and genetic diversity essential to long-term crop and livestock production. -sustainable agriculture is agriculture that can be practiced in the same way in the same place far into the future. Ex: No-till farming and other soil conservation methods

Mt top removal and effects

-Entire mountain tops are blasted off and the waste is dumped into valleys (valley fills). -Common method of coal mining in the Appalachian Mountains of the eastern U.S. -Economically efficient (for the mining company Cons: -water pollution -landscape damage -Clear cut forests -Valley filling -Stream destruction -Acid drainage -Erosion -Mudslides -Flash floods -Health impacts (coal dust) --"Coal dust causes respiratory ailments, and contaminated water unleashes a variety of health problem" TB -When a resource occurs in underground seams near the tops of ridges or mountains, this can be the mining method of choice -several hundred vertical feet of mountaintop are removed to allow recovery of entire seams of the resource -mountain's forests are clear-cut and the timber is sold, topsoil is removed, and then rock is repeatedly blasted away to expose the coal for extraction. -Over-burden is placed back onto the mountaintop, but waste rock is unstable and takes up more volume than the original rock, -so a great deal of waste rock is dumped into adjacent valleys (a practice called "valley fill- ing"). Dumping tons of debris into valleys --degrades or destroys immense areas of habitat, --clogs streams and rivers --pollutes waterways with acid drainage. With slopes deforested and valleys filled with debris:, --erosion intensifies, --mudslides become frequent --flash floods ravage the lower valleys -loose rock tumbles down into yards and homes

Other transport mechanisms

-Many chemicals are soluble in water and enter organisms' tissues through drinking or absorption. -aquatic animals such as fish, frogs, and stream invertebrates are effective indicators of pollution

Placer Mining $

-Sift minerals from streams -Dense minerals are carried by flowing water -Ex: gold, gems Cons - Social impacts - Stream debris --- large amounts of debris are washed into streams ---uninhabitable for fish and other life - Damages stream banks (causing) - Erosion

Climate

-an area's long-term atmospheric conditions - -Temperature, moisture, wind, precipitation, etc. How is that different than weather? -weather is short term?

What are potential solution to some problems w/ GMO????????

-biological pest control -organic agriculture -pollinator conservation -preservation of native crop diversity -sustainable aquaculture,

Environmental effects of fossil fuels: Hg

-combusting coal high in mercury can AFFECT HUMAN HEALTH -Bioaccumulation or biomagnification: concentration of a toxin increases as you go up the food web TB -Combusting coal high in mercury content emits mercury that can BIOACCUMULATE in organisms' tissues (this poisons animals as it moves up food chain) Example from textbook: "1) Organisms at the lowest trophic level take in fat-soluble compounds such as DDT from water. 2) As animals at higher trophic levels eat organisms lower on the food chain, each organism passes its load of toxicants up to its consumer 3) such that organisms on all trophic levels bioaccumulate the substance in their tissues. -at-soluble or oil-soluble (including organic compounds such as DDT and DDE) are absorbed and stored in fatty tissues. Substances such as methyl mercury can be stored in muscle tissues -toxicants accumulate in an animal's body in a process termed BIOACUMULATION, such that the animal's tissues have a greater concentration of the substance than exists in the surrounding environment. -Toxic substances that bioaccumulate in an organism's tissues may be transferred to other organisms as predators consume prey. -When one organism consumes another, the predator takes in any stored toxicants and stores them itself. -Thus bioaccumulation takes place on all trophic levels. - each individual consumes many individuals from the trophic level beneath it, ---so with each step up the food chain, concentrations of toxicants become magnified. This process, called BIOMAGNIFICATION, -occurred throughout North America with DDT. ---Top predators, such as birds of prey, ended up with high concentrations of the pesticide because concentrations became magnified as DDT moved from water to algae to plankton to small fish to larger fish and finally to fish-eating birds ---cause: North American birds of prey to decline precipitously -

FF effect on ecosystem $

-pollute air -drive climate change • Sox and NOx (sulpher dioxide and nitrogen oxide) are released by COAL PP & other sources ("largely through fossil fuel combustion by automobiles, electric utilities, and indus- trial facilities) • May form wet deposition (acid rain, acid fog) or dry deposition. • Acid precipitation generally has a pH of ~4.5, but can get to 3.0 or lower. • Some ecosystems have alkaline (basic) soils that can neutralize effects. -lower ph=more acidic TB: -Sulfur dioxide and nitric oxide emitted by industries and utilities are transformed into sulfuric acid and nitric acid through chemical reactions in the atmosphere. -acidic compounds descend to Earth's surface in rain, snow, fog, and dry deposition. -by precipitation (commonly referred to as acid rain, but also including acid snow, sleet, and hail), -by fog -by gases, -by the deposition of dry particles fossil fuel emissions negatively affect human health. MERCURY -Combusting coal high in mercury content emits mercury that can bioaccumulate in organisms' tissues, poisoning animals as it moves up food chains -presenting health risks to people. -Gasoline combustion in cars releases pollutants that irritate the NOSE/THROAT/LUNG. -Some hydrocarbons, such as benzene and toluene, cause CANCER in laboratory animals and likely in people. -Gases such as hydrogen sulfide can evaporate from crude OIL, irritate the EYES/THROAT, and cause ASPHYXIATION. -Crude OIL also often contains trace amounts of known poisons such LEAD ARSENIC . ---As a result, workers at drilling operations, refineries, develop health problems, including CANCER combustion of oil in our vehicles and coal in our power plants releases SULFUR DIOXIDE AND NITROGEN OXIDES - contribute to INDUSTRIAL AND PHOTOCHEMICAL SMOG -and to ACID DEPOSITION Fossil fuel pollution is intensifying .

Alleviating Environmental impacts of FF

-§ Costs of alleviating environmental impacts are not internalized in the market price of fossil fuels § Gas prices and utility bills don't cover production costs § Government subsidies keep fossil fuel prices cheap (cheap gas) § estbl. Fossil fuel industries get more $$ from taxpayers than renewable energy source

How farmers protect soil

1) Crop Rotation 2) Contour farming 3) Terracing 4) Intercropping 5) Shelterbelts 6) Conservation tillage

Alternatives to pesticides

1) Crop Rotation -switching crops seasons/years --"reduces insect pests; if an insect is adapted to feed and lay eggs on one crop, planting a different type of crop will leave its offspring with nothing to eat" 2) Intercropping --bands of different crops 3) Biological control: using organisms that eat pests. --Example: Lady bugs are a natural predator of aphids --cactus moths ("Larvae of this moth used to clear invasive non-nativeprickly pear cactus from millions of hectares of rangeland".) 4) Integrated pest management ("combines biocontrol and chemical methods (natural chemicals) " 5) genetic control???? TB BIOLOGICAL CONTROL/BIOCONTROL: battle pests and weeds with organisms that eat or infect them. -operates on the principle that "the enemy of one's enemy is one's friend." 79 For example, parasitoid wasps are natural enemies of many caterpillars. These wasps lay eggs on a caterpillar, and the larvae that hatch from the eggs feed on the caterpillar, eventually killing it. Parasitoid wasps are frequently used as biocontrol agents and have often succeeded in controlling pests and reducing chemical pesticide use. --risky, because no one can know for certain what effects the biocontrol agent might have. In some cases biocontrol agents have turned invasive and become pests themselves INTEGRATED PEST MANAGEMENT - Integrated pest management (IPM) incorporates numerous techniques, including biocontrol, use of chemicals when needed, close monitoring of populations, habitat alteration, crop rotation, transgenic crops, alternative tillage methods, and mechanical pest removal.

Dust Bowl

1930s drought + erosion caused "black blizzards" of sand • Total wheat production dropped 45%! TB Drought and poor agricultural practices devastated millions of U.S. farmers -Farmers grew abundant wheat and ranchers grazed many thousands of cattle, sometimes expanding onto unsuitable land and causing erosion by removing native grasses and altering soil structure. -DROUGHT worsened the ongoing human impacts -Region's strong winds began to erode millions of tons of topsoil -The "black blizzards" of the Dust Bowl forced thousands of farmers off their land.

No-till Farming benefits $

@no-till farming: crops are replanted without tilling the ground -DOESNT disturb lower soil layers. Pros - nutrients from the previous year's crop are able to break down and return to the soil --reduces erosion & need for fertilizer. TB • Reduces erosion • Helps soil retain moisture • Enhances soil structure • Reduces soil compaction • Stores carbon in soil, lessening its release to the atmosphere • Improves biological activity in soil • Helps soil retain nutrients • Cuts down on water and air pollution • Requires less time and labor • Decreases fossil fuel use and costs • Minimizes wear and tear on equipment • Tends to increase long-term soil productivity, crop yields, and farming profit 228

Prevalence of chemicals in our environment -the air, water, and soil -Synthetic chemicals in U.S. ???

Air, water, and soil: • 80% of U.S. streams contain 82 contaminants • 92% of all aquifers contain 42 volatile organic compounds (VOCs - from gasoline, paints, plastics, etc.) Synthetic/U.S. • Every one of us carries traces of hundreds of industrial chemicals in our bodies! • Babies are born "pre-polluted" - 232 chemicals were in umbilical cords of babies tested • Not all chemicals pose health risks, but very few have been tested

How toxin enter our environment ??

Application of Pesticides and herbicides (review) Surface water contamination (review) -streams, lakes, rivers -become polluted when rainwater runoff carries pollutants into the water -ex: salt, chemicals, fertilizers -Fetilizer-overproduction of algae and other aquatic plants-cover the water surface and prevent sunlight from reaching the plants underwater-less oxygen produced-oxygen breathing animals suffer (fish) Disease in surface water -sewage, runoff from animal factory Chemicals pesticides, synthetic chemicals such as petroleum products and other car fluids, and mercury, lead and arsenic from mining site drainage - Groundwater contamination (review) water below earth -agricultural runoff, toxic chemicals from spills and drainage and pathogens, septic tanks, underground oil tanks -pesticides leaching directly in through the soil. - Air pollution (review) - Other transport mechanisms

Fossil fuels overview - What they are

Are organic remains from fossils that we can burn for fuel. Highly combustible substances from the ancient remains of organisms. -Efficient to burn, store, ship 3 main: coal, oil, and natural gas TB When plants and other organisms die and are buried in sediments under particular conditions, their stored chemical energy may eventually be transferred to fossil fuels, highly com- bustible substances formed from the remains of organisms from past geologic ages.

Terracing Countour Farmer

Both To prevent or minimize erosion via water: T: Level platforms cut into steep hillsides "to contain water from irrigation or precipitation" -prevents runoff? C: plowing perpendicular across a hill TB T "On very steep terrain, terracing is the most effective method for reducing erosion." -transforms slopes into series of steps like a staircase, enabling farmers to cultivate hilly land without losing huge amounts of soil to water erosion. -$ in mountainous regions, such as the foothills of the Himalayas and the Andes. C- "Water running down a hillside with litte plant cover can carry soil away, so farmers have developed methods for cultivating slopes." -plowing furrows sideways across a hillside, per- pendicular to its slope and following the natural contours of the land. -side of each furrow acts as a small dam that slows runoff and captures soil. - most effective on gradually sloping land with crops that grow well in rows. @ -plowing and planting along the land's natural contours. -When water is forced to travel this way, it slows down, gives the water time to seep back into the soil, which helps keep both the soil and its nutrients in place.

Alberta's Oil Sands and the Keystone XL Pipeline

Canada's oils sands (or tar sands) are layers of sand or clay saturated with a viscous, tarry type of petroleum called bitumen -The oil sands produce 1.7 million barrels of oil per day -United States major purchaser STRIP Mining them for oil bad impacts -pollution -threaten earths climate Keystone XL Pipeline -The TransCanada Corporation wants to build this extension to deliver more oil more quickly all the way to Texas For: -jobs Against: -destruction of the boreal forests in Canada -potential for an oil spill over the Ogallala Aquifer in the United States -"greenhouse gas emission, climate change" TB Keystone Pipeline=ship diluted bitumen into the United States. - oil from Alberta to Illinois and Oklahoma -Keystone XL extension would include (1) a southern leg to connect Cushing to the Texas refineries and (2) a northern leg that would cut across the Great Plains to shave off distance and add capacity to the existing line.

Air pollution

Chemicals can travel far and wide by air •Synthetic chemicals are found globally (wind?) - Arctic polar bears - Antarctic penguins - People in Greenland 1) at low latitudes evaporation of pollutants exceed deposition (buildup) 2) Pollutants are transported by atmosphere (wind) and ocean currents 3)At high latitudes, deposition of pollutants exceeds evaporation 4) Pollutants enter the polar food web and accumulate in biota TB -released around the world from agriculrural, industrial, and domestic activities and can sometimes be redistributed by air currents -Because so many substances are carried by the wind, synthe tic chemicals are ubiquitous worldwide, -Earth's polar regions are particularly contaminated, because natural patterns of global atmospheric circulation tend to move airborne chemicals toward the poles --Thus, although we manufacture and apply synthetic substances mainly in temperate and tropical regions, --contaminants are strikingly concentrated in the tissues of Arctic polar bears, Antarctic penguins, and people living in Greenland.

NEGATIVE Environmental effects of fossil fuel emissions

Coal -produces carbon dioxide (global waming) -acid rain (coal)

Coal

Coal is a solid form of fossil fuel -formed when organic matter (usually woody plant material) is compressed under very high pressure "creating dense, solid carbon structures" -results in the absence of decomposition. --"because the material cannot be digested or appropriate decomposers are not present." Powered the industrial revolution --"bc Coal-fired steam engines powered factories, agriculture, trains, and ships, and by fueling the furnaces of the steel industry" TB -world's most abundant FF -generate electricity. In coal-fired power plants: 1) coal combustion converts water to steam, 2) which turns a turbine to create electricity Coal provides 40% of the electrical generating capacity of the United States -as heat and pressure increase, and as time passes, water is squeezed out and carbon compounds are packed more tightly together, forming coal. -The more coal is compressed, the greater is its carbon content and the greater is the energy content per unit volume. - Heat from the combustion boils water, and the resulting steam turns a turbine, generating electricity by passing magnets past copper coils. The steam is then cooled and condensed in a cooling loop and returned to the furnace. "Clean coal" technologies (p. 537) help filter pollutants from the combustion process, and toxic ash residue is taken to hazardous waste disposal sites.

Oil and how its formed

Crude oil (petroleum): -liquid contains hundreds of types of hydrocarbons from organic material in marine sediments, and transformed by time, heat, and pressure TB Used as fuel for vehicles, --gasoline for cars, --diesel for trucks, --jet fuel for airplanes. industry and manufacturing Wide array of products and applications: -plastics -lubricants -fabrics -pharmaceuticals.

Climate change and water supply -Drought *******

Drought is a lengthy period of abnormal shorting in precipitation. TB Global climate change will worsen conditions in many regions by changing precipitation patterns --intensifying droughts and flooding. Ways to make water more sustainable: . Drip irrigation -native crops -water night -low-flow faucets -reclaimed water

U.S. Toxic Substances Control Act

EPA monitors chemicals made in or imported into the U.S. and can ban them • Many health advocates think the TSCA is too weak - Of 83,000 chemicals, only five have been restricted - To push for more testing, toxicity must already be proven, but testing is minimal • Only 10% of chemicals have been tested for toxicity - Fewer than 1% are regulated - Almost none have been tested for endocrine, nervous, or immune system damage TB -Synthetic chemicals not covered by other laws are regulated by the EPA under the 1976 Toxic Substances Control Act -directs the EPA to moni- tor thousands of industrial chemicals manufactured in or imported into the United States, ranging from PCBs to lead to asbestos, and including bisphenol A, and plastic -gives the agency power to regulate these substances and ban them if they are found to pose excessive risk. -To push for studies looking for toxicity, it must have proof of toxicity already. The result is that most synthetic chemicals are not thoroughly tested before being brought to market. Of those that fall under TSCA, only 10% have been thoroughly tested for toxicity; only 2% have been screened for carcinogenicity, mutagenicity, or teratogenicity; fewer than 1% are regulated; and almost none have been tested for endocrine, nervous, or immune system damage,

Eutrophication

Excessive inputs of phosphorus and nitrogen causes Eutrophication - abnormally high productivity in a body of water 1) Excess use of chemical fertilizers leads to run off and group water contamination 2) The inorganic salts dissolved ground water eventually enter lakes, ponds, and rives 3) Increased nuturtients absorbed by algae 4) Increased decomposition of dead algae uses up oxygen in the water 5) Increased growth of algae shades out other plants 6) Fish die as oxygen levels fall TB ex: phytoplankton blooms in the Gulf of Mexico and creates an oxygen-depleted "dead zone" that kills fish and shrimp @ -process where a body of water becomes overly enriched by nutrients. --overabundance of nutrients accelerates fast growth of algae and aquatic plant life. - growth depletes dissolved oxygen levels within the water (causes other organisms, such as fish to die) -this is typically the result of human activities that contribute lots of nitrogen and phosphorus into water. -Agricultural fertilizer(contain nirogen and phosphorous) -fertilizers can cause these nutrients to runoff of the farmer's field and enter waterways

FF - Where they are distributed (sources)

FF reserves are UNEVENLY distributed • Most crude oil: Middle East (~67%) • Most natural gas: Russia • Most coal: U.S. => geopolitical implications TB most energy sources also are unevenly distributed over Earth's surface. Some regions have substantial reserves of oil, coal, or natural gas, whereas others have very few. $Coal 1) US 2) Russia 3) China

Genetically modified organisms (GMOs) -Benefits -Drawbacks ****

Genetic engineering: laboratory manipulation of genetic material (DNA) (GMOs): organisms that have been genetically engineered by inserting DNA from multiple organisms --ex:Monsanto company engineered "Roundup Ready" crops. These crops can be sprayed by herbicides, but survive. Ex: soybeans (47) corn (32) Cotton (14) canola (5) • Possible benefits (?): - Reduced use of chemical pesticides, at least initially - Decrease deforestation & land conversion --"Crops that increase yields on existing farmland help con- serve biodiversity and ecosystem services because they reduce pressure to clear forests and convert natural lands for agriculture." • Possible drawbacks (?): - Evolved resistance ---"@pests experience constant exposure to the pesticide or herbicide that is genetically inserted into the crops, they will develop genetic resistance to the chemical - Increased pesticide use affects health and habitats --"because farmers often apply more herbicide if their crops can withstand it " -Some GM fields support less biodiversity - Possibility of interbreeding w/ native species? ----@could potentially out-compete native non-pest organisms or prey on non-pest organisms. These new organisms could also interbreed with native organisms and create new species that may not be desirable. TB -The goal is to place genes that produce certain proteins and code for certain desirable traits (such as rapid growth, disease resistance, or high nutritional content) into the genomes of organisms lacking those traits. -Most GM crops today are engineered to resist herbicides, so that farmers can apply herbicides to kill weeds without having to worry about killing their crops. -Other crops are engineered to resist insect attack (resist insecticides) . -Some are modified for both resistance. - Resistance to herbicides and pests lets large-scale commercial farmers to grow crops more efficiently ---- Crops engineered for drought tolerance can help save water by reducing the need for irrigation. • Raising food yields while lowering production costs for farmers enhances food security for society. @ Positive: Increased yields -resistance -grow crops in regions that wouldn't normally be suitable -reducing the amount of chemical pesticides and fertilizers, there will be less harm done to the environment -new varietyy of crops Problems -pests experience constant exposure to the pesticide or herbicide that is genetically inserted into the crops, they will develop genetic resistance to the chemical -

Global warming

In class -an aspect of global climate changes -other parts might get more cold, more parciptiatin... is an increase in Earth's average temperature. -ONLY 1 aspect of climate change

How toxins affect humans and other organisms

Individuals vary in their responses to hazards • Different people respond differently to hazards - Some people are more genetically sensitive to certain hazards - People in poor health are more sensitive - Sensitivity also varies with sex, age, and weight - Fetuses, infants, and young children tend to be most sensitive TB -Because of their smaller size and rapidly developing organ systems, younger organisms (for example, fetuses, infants, and young children) tend to be much more sensitive to toxicants than are adults.

Groundwater Depletion 233 -Chapter 15, 393*******

Irrigation is inefficient -"plants end up using only 43% of the water that we apply -rest evaporates/soaks into the soil away from plant roots" -Conventional methods are inefficient (waste). -Drip irrigation systems (hoses drip water directly onto the plants), less wasted • We use 70% more irrigation water than 50 years ago • Ogallala Aquifer now 50% depleted • Surface water and groundwater are connected (depleting one influences the other) • Bottom line => unsustainable use of groundwater Consumption of water in most of the world is unsustainable! TB -Irrigation=The artificial provision of water beyond that which crops receive from rainfall -ppl r withdrawing water at unsustainable levels and are depleting many sources of surface water and groundwater. -$we allot about 70% of our annual fresh water use to agriculture. -When we remove water from an aquifer or surface water body and do not return it= consumptive use. -IRRIGATION (water applied to crops) is primary consumptive use of water --withdrawing water for irrigation has depleted aquifers and dried up rivers and lakes -----$farmers affected by cost/availbiity of water -Green Revolution -> increases in irrigation -> we withdraw 70% more water for irrigation than we did 50 years ago -doubled the amount of land under irrigation @ Effects of overdrawing: -saline, or have a higher salt concentration -plants animals affected Ground . -sinkholes -loss of land-agriculture -dried up wells -less water reaching streams, rivers and lakes, dried up wells, a lowered water table and salt water entering the groundwater supply.

- Epidemiological studies

Large-scale comparisons between exposed and unexposed groups (to hazard) - Studies can last for years - Yield accurate predictions about risk - Measure an association between a health hazard and an effect - but not necessarily the cause of the effect TB -similar to natural experiment Advantages: -realism --their ability to yield relatively accurate predictions about risk. Disadvantages: -need to wait a long time for results -inability to address future effects of new hazards, such as products just coming to market. -participants encounter many factors that affect their health besides the one under study. -measure a statistical association between a health hazard and an effect, --BUT THEY DO NOT confirm that the hazard causes the effect. -Manipulative experiment needed 2 establish causation -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. -then analyzes the data, looking for observable differences between the groups, -then statistically tests hypotheses accounting for differences. -When a group exposed to a hazard shows a signifi- cantly greater degree of harm, it suggests that the hazard may be responsible. Ex: -epidemiologists have tracked asbestos miners for evidence of asbestosis, lung cancer, and mesothelioma -Survivors of the Chernobyl and Fukushima nuclear disasters have been monitored for thyroid cancer and other illnesses -Canadian epidemiologists are now tracking people for impacts of bisphenol A exposure.

What is mining?

Mining is the extraction of valuable minerals or other raw materials from the earth "if you can't make it or grow it, you must mine it" TB -describes the extraction of any resource that is nonrenewable on the timescale of our society. --In this sense, we mine fossil fuels and groundwater, as well as minerals. --When used specivically in relation to minerals, mining refers to the systematic removal of rock, soil, or other material for the purpose of extracting minerals of economic interest

Natural Gas

Natural gas: gas consisting primarily of methane (CH4) and including varying amounts of other volatile hydrocarbons. methane CH4 and other volatile hydrocarbons - relatively clean • Emits 50% the CO2 per unit energy produced as coal, and 40% less than oil. • It can be refrigerated and transported in refrigerated tankers, or as a gas through gas lines. TB -use natural gas to generate electricity in power plants, to heat and cook in our home -Converted to a liquid at low temperatures (liquefied natural gas, or LNG), it can be shipped long distances in refrigerated tankers. - When we replace coal with natural gas to generate electricity, this cuts carbon emissions in half. -U.S. and Russia

Greenhouse Effect

Notes -incoming short wave raditation (visible light) passes through atmosphere (why we see most of the light coming into earth) -when it comes in, ground absorbs it, (and trees, parking lots, etc...) -when it absorbs it switches to IR (in fared radiant)

Air and water pollutants (some review) -- Oil spills -- Mercury (Hg) pollution

OIL NEGATIVE EFFECT ON ECOSYSTEM ($Oil transported by ships-> oil spills) -contaminate ground water -contamination affectes fresh water ecosystems Bp's 2010 Deepwater Horizon oil spill was the largest accidental oil spill in world history • Major oil spills make headlines Foul beaches --"indirect economic and social impacts" - Coat and kill animals = -----"bird, fihn, shrimp, corals, killed" ----"coastal and ocean ecosystems affected" - Devastate fisheries • But countless small non-point sources produce most oil pollution - Runoff - Small boat leaks TB -All our actions contributes: "Oil from automobiles, homes, industries, gas stations, and businesses runs off roadways and enters rivers and wastewater facilities, being discharged eventually into the ocean. -Oil can contaminate groundwater supplies when: -- pipelines rupture --underground storage tanks containing petroleum products leak. -Atmospheric deposition of pollutants from the combustion of fossil fuels exerts many impacts on freshwater ecosystems. TB --Plants in coastal marshes died, and the resulting erosion of marshes put New Orleans and other coastal cities at greater risk from storm surges and flood- ing. In 2010, BP's Deepwater Horizon offshore drilling platform exploded and sank off the coast of Louisiana - revealed that offshore drilling presents serious risks of environmental impact

Soil degradation mechanisms: erosion 223

Occurs via water and wind TB Erosion= the removal of material from one place and its transport toward another by the action of wind or water -Problem for ecosystems and agriculture bc it tends to occur much more quickly than soil is formed -Tends to remove topsoil (the most valuable soil layer for living things) -When eroded soils are carried out to sea, their nutrients are lost to terrestrial systems. -Most wind erosion= Windy regions w/ sparse plant cover -Most water erosion= areas w/ steep slopes, high precipitation, and sparse vegetative cover People have made land more vulnerable to erosion in three ways: 1) Overcultivating fields (through poor planning or excessive tilling) @SAME crops grown -- specific nutrients may become totally depleted from the soil, which decreases the richness of the soil. And, when this happens, soil is more easily washed away by wind and water. 2) Grazing rangeland with more livestock than the land can support 3) Clearing forests on steep slopes or with large clear-cuts (317) --@ increases erosion rates because it removes the roots of trees, which act as anchors and help hold the soil in place Water erosion can readily remove soil from areas where soil is exposed, such as farmland. @ Effects of soil erosion -soil erosion = that the land is being removed. -This creates problems because much of the land is agricultural land, which is what we need for growing crops. -Soil erosion also creates water pollution. --The sediments that are being carried away often end up in streams, rivers, lakes, and oceans. These sediments carry with them all of the fertilizers, pesticides, leaked car fluids, and other toxins present, and then transport them into aquatic systems. This not only creates unsafe drinking water for humans, but also creates unlivable environments for the fish, mammals, reptiles, and other organisms that call these places home. Air pollution - air that we breathe. -They may also end up in the water at some point if those particles get taken up into rain and snow clouds, which then drop them back to Earth and into aquatic systems.

• Peak oil concept

PEAK IN PRODUCTION § We have used up 1.1 trillion barrels of oil, which is half our reserves! --oil crisis § At current levels of production (30 billion barrels/year), we have about 40 years of oil left § Peak oil: rate of production PEAKS and then declines § We will face a crisis not when we run out of oil, but when the rate of production begins to decline TB "the point of maximum production of petroleum in the world (or given nation), after which oil production declines -also expected to be roughly midway point of extraction of world's oil supplies -Regardless of how many years' worth of a resource we might calculate to be left, a society dependent on that resource will face a crisis not when the last bit of it is extracted from the ground, but rather once the rate of its production comes to a peak and begins to decline. Once we pass this peak and production begins to decline: -The resulting divergence of supply and demand would drive up oil prices, causing substantial economic ripple effects. Although high oil prices will provide financial incentive to develop alternative energy sources and better conservation measures, we may be challenged in a depressed economy to find adequate time and resources to develop new renewable sources. -Because we have already used roughly half of Earth's conventional oil reserves, many experts calculate that a peak oil crisis may well begin in the very near future.

Mining PP

PP

Agriculutre

PP2

Pest -Problems of pests

Pest: insects and weeds -traditional weeding leads to soil loss -tilling leads to soil loss? TB -affect farm productivity PEST = any organism that damages crops that are valuable to us. --ex: insect that feeds on corn, grapes, or apples, encountering a grain field, vineyard, or orchard is like discovering an endless buffet. WEED = any plant that competes with our crops. -Pests pose an especially great threat to monocultures, where a pest adapted to specialize on the crop can move easily from plant to plant -Pests evolve resistance to pesticides -

• Reclamation of mined sites and problems w/ it

Reclamation aims to bring a site to a condition similar to its pre-mining condition - Remove mining structures, replace soil, replant vegetation • The U.S. 1977 Surface Mining Control and Reclamation Act mandates restoration - Other nations (Congo) have no regulations at all Problems with restoration: • Same biotic community never regained --• Symbiotic relationships not regained ------"specialized relationships that maintain ecosystems... ex: plants and fungi and plants and insects") • Forests slow growing (grasses) • Nutrient poor soils • Water quality difficult to restore --• Remove heavy metals --• Neutralize pH TB Because of the environmental impacts of mining, governments of the United States and other developed nations now require that mining companies restore, or reclaim, surface-mined sites following mining. To restore, companies are required to remove buildings and other structures used for mining, replace overburden, fill in shafts, and replant the area with vegetation . In the United States, the 1977 Surface Mining Control and Reclamation Act mandates restoration efforts, requiring companies to post bonds to cover reclamation costs before mining can be approved. --ensures that if the company fails to restore the land for any reason, the government will have the money to do so. CONS: -impacts from mining (such as soil and water damage from acid drainage) can be severe and long- lasting. BIOTIC COMMUNITIES - 1: fast-growing grasses are generally used to initiate and anchor restoration efforts. --helps control erosion quickly from the outset, but it can hinder the longer-term establishment of forests, wetlands, or other complex natural communities. ---instead, grasses may outcompete slower-growing native plants in the acidic, compacted, nutrient-poor soils that usually result from mining.

Sustainability/Recycling

Recycling addresses 2 major challenges w/ mineral resources: - Finite supplies - Environmental damage • 35% of metals were recycled in 2008 from U.S. municipal solid waste - 7 million tons (of metals that U.S. consumers recycle each year reduce greenhouse gas emissions by 25 million metric tons of carbon dioxide) -Things recycled: Steel, iron, platinum, gold,nickel, tin, and more ("lead, copper chromium, zinc, aluminum") TB -municipal recycling programs help provide metals by handling used items that we as consumers place in recycling bins and divert from the waste stream. In 2010, fully 35% of metals in the U.S. municipal solid waste - can decrease energy use substantially. --ex: making steel by remelting recycled iron and steel scrap requires much less energy than producing steel from virgin iron ore. --bc practice saves money, the steel industry today is designed to make efficient use of iron and steel scrap. (Over half its scrap comes from discarded consumer items such as cars, cans, and appliances); - 40% of the aluminum in the US is recycled . --=good bc it takes over 20 times more energy to extract virgin aluminum from ore (bauxite) than it does to obtain it from recycled sources. Saving energy =cutting down on pollution from fossil fuel combustion. All in all, the 7 million tons , the Environmental Protection Agency estimates. This reduction is like taking more than the yearly emissions of 4.5 million cars out of the atmosphere.

- Case history approach

Studies individual patients - Autopsies tell us about lethal doses - Don't tell about rare, new, or low-concentration toxins - Don't tell about probability and risk TB -studying sickened individuals directly -process of observation and analysis of individual patients is known as a case history approach - - have advanced our understanding of human illness, ---but they do not always help us infer the effects of rare hazards, new hazards, or chemicals that exist at low environmental concentrations and exert minor, longterm effects -tell us little about probability and risk, such as how many extra deaths we might expect in a population due to a particular cause.

$ Soil

TB - vital for agriculture,forests, and functioning of Earth's natural systems. -it is a complex system consisting of disintegrated rock, organic matter, water, gases, nutrients, and microorganisms. - renewable resource. --Once depleted, can renew itself over time, but renewal generally occurs very slowly. --If we abuse soil through careless or uninformed practices, we can greatly reduce its ability to sustain life. - most farming and grazing that people have practiced so far have depleted soils faster than they form, it is imperative for our civilization's future that we develop sustainable methods of working with soil. -Sustainable agriculture allows soil to renew its nutrient content and retain its character from one crop to the next. -Crop plants depend on soil that contains organic matter to provide the nutrients they need for growth. -Plants also need soil with a structure and texture suitable for roots to penetrate deeply. -And plants need soil that retains water and makes water and dissolved utrients accessible to their roots. Livestock also depend on soil with these characteristics, because livestock eat plants that have grown in the soil. If soil becomes degraded, then agriculture suf- fers. Because everyone in our society relies directly on agricul- ture for the meals we eat and the clothing we wear, the quality of our lives is closely tied to the quality of our soil. Healthy soil has sustained agriculture for thousands of years. When people first began farming, they were able to take advantage of deep, nutrient-rich topsoil that had built up over vast spans of time. Today we face the challenge of produc- ing immense amounts of food from soil that has been farmed many times, while also conserving its fertility for the future

Extracting coal

TB -Coal is a solid, and so we MINE IT not drill Coal deposits near surface: -STRIP MINING --soil is removed from the surface in strips, exposing seams from which coal is mined. --most effective mining method Deep underground: SUBSURFACE MINING -method when coal seams are not horizontal ---miners work belowground in shafts and tunnels blasted through the rock. These passageways provide access to underground seams of coal or minerals. ---digging vertical shafts and blasting out networks of horizontal tunnels to follow seams, or layers, of coal. MOUNTAINTOP REMOVAL -on immense scales in the Appalachian Mountains, essentially scraping off entire mountaintops --occurs when coal is in underground seams near the tops of ridges or mountains ---a mountain's forests are clear-cut and the timber is sold, topsoil is removed, and then rock is repeat- edly blasted away to expose the coal for extraction.

Groundwater contamination

TB -If chemicals persist in soil, they can leach into groundwater and contaminate drinking water supplies. -contaminants that wash into streams and rivers also flow and seep into the water we drink and drift through the air we breathe. -Once concentrated in waters, toxic substances can move long distances and AFFECT ECOSYSTEMS @water below earth -agricultural runoff, toxic chemicals from spills and drainage and pathogens, septic tanks, underground oil tanks -pesticides leaching directly in through the soil.

Surface water contamination

TB -Water running off from land often transports toxicants from large areas and concentrates them in small volumes of surface water @ --streams, lakes, rivers -become polluted when rainwater runoff carries pollutants into the water -ex: salt, chemicals, fertilizers -Fetilizer-overproduction of algae and other aquatic plants-cover the water surface and prevent sunlight from reaching the plants underwater-less oxygen produced-oxygen breathing animals suffer (fish) Disease in surface water -sewage, runoff from animal factory Chemicals pesticides, synthetic chemicals such as petroleum products and other car fluids, and mercury, lead and arsenic from mining site drainage

Pesticides and herbicides

TB -can be carried by air currents to sites far from agricultural fields in a process called pesticide drift. S @ Surface water -chemicals Groundwater -pesticides can leach directly in through soil

How oil and gas are formed TB$

TB -formed from organic material (especially dead plankton) -that drifted down through coastal marine waters millions of years ago and was buried in sediments on the ocean floor. -As organic matter is buried more deeply, the pressure exerted by overlying sediments grows, and temperatures increase. -Carbon bonds in the organic matter begin breaking, and the organic matter turns to a substance called kerogen, which acts as a source material -. Further heat and pressure act on the kerogen to degrade complex organic molecules into simpler hydrocarbon molecules. Oil tends to form under temperature and pressure conditions often found 1.5-3 km (1-2 mi) below the surface. Natural gas forms w/ the high temperatures and pressure --At depths below 3 km (1.9 mi)

Resources we extract from mining

TB -fossil fuels and groundwater -minerals.

FF Non-renewability -(refer to sustainability card)

TB nonrenewable fuels result from ongo- ing natural processes, but it takes so long for fossil fuels to form that, once depleted, they cannot be replaced within any time span useful to our civilization.

EPA? $coal#

The EPA sets nationwide standards for emissions and concentrations of toxic pollutants • Criteria pollutants: pollutants that pose especially great threats to human health - particulate matter (PM) - carbon monoxide (CO) - sulfur dioxide (SO2) - nitrogen dioxide (NO2) - tropospheric ozone (O3) (vocs form o3) - lead (Pb) In 2012, the U.S. emitted 85 million tons of the six monitored pollutants FOSSIL FUEL: • SOx and NOx are released by COAL burning power plants & other sources. • May form wet deposition (acid rain, acid fog) or dry deposition. • Acid precipitation generally has a pH of ~4.5, but can get to 3.0 or lower. • Some ecosystems have alkaline (basic) soils that can neutralize effects.

FF - US energy flow

The U.S. energy stream is dominated by coal, oil, and natural gas GRAPH -Transportation (mostly oil) -Industrial (gas most, oil) -Commercial -Residential -Electrical generation (coal most, gas, nuclear, ewnewablesn TB --oil, coal, and natural gas together supply 82% of energy flow $ U.S.'s EROI ratios for oil and gas DECLINED - because we extracted the easiest deposits first and now must work harder and harder to extract the remaining amounts. -takes energy to make energy - assessing energy sources, it is useful to use a ratio often denoted as EROI EROI = Energy returned/Energy invested Higher EROI ratios =we receive more energy than we invest. -Fossil fuels used a lot because their EROI ratios have been high. --Ratios rise as the technology to extract and process fossil fuels improves ---fall as resources are depleted and remaining resources become harder to extract.

FF - Global trends in consumption

The U.S. has 4.5% of the population but uses 20% of the world's energy @ huge difference between developed (industrialized) nations and developing countries TB -Annual global consumption of fossil fuels has risen greatly over the past half-century. Oil remains our leading energy source -People in wealthy industrialized nations tend to consume the most energy per person. --(Industrialized person 100 times more) INDUSTRIALIED -one-third of their energy to trans- portation, -one-third to industry, -one-third to all other uses. Industrializing -subsistence activities such as agriculture, food preparation, and home heating, and much less to transportation. DEVELOPING -rely on manual or animal energy sources instead of automated ones. -rely less on equipment and technology, they use LESS fossil fuel -The average U.S. citizen uses 7.28 tons per yea -Average person. uses 1.76 tons per yea .

drawbacks of pesticides

Toxicity - can harm animals (even ppl) -• Pesticides runoff into water bodies • ex: effects of atrazine?: (frogs, female) -Pesticides can kill pollinators (beneficial insects) Persistance -Some toxins can degrade quickly and become harmless -BUT others remain, don't change (unaltered*), and persist for years and years and decades --ex: Malathion degrades to malaoxon = even more toxic --ex: DDT: Even though DDT was banned in the USA 1973, it lasts for years in the environment bc it persists Residues & Drift • Most of our produce is coated with many different chemicals • These chemicals can contaminate soil, drift to nearby ecosystems --ex: Effects of herbicide drift/potato Resistance -Through the process of natural selection, crop pests (insects) often evolve resistance to the poisons we apply to kill them: 1) Pests attack crops 2) Pesticides applied 3) Most pests are killed. A few with innate resistance survive 4) Survivors breed and produce a pesticide-resistant population 5) Pesticide is applied again 6) Pesticide has little effect. New, more toxic, pesticides are developed Summary: • Toxic to humans and other animals: - Can cause fertility problems, cancer, etc. - Can kill "good" insects (like pollinators) - Can bioaccumulate and biomagnify - Unknown effects • Easily enters environment via runoff and drift • Persistence in the environment • Residues on food products (including from drift) • Evolved resistance (pesticide becomes ineffective) TB - health consequences for people and other organisms under some circumstances, so their use in food production can have far-reaching effects. -pesticides often kill non- target organisms, --including the predators and parasites of the pests. -When these valuable natural enemies are eliminated, pest populations become harder to control. -Two accidentally introduced parasitic mites have swept through honeybee populations, decimating hives and pushing beekeepers toward financial ruin -All insect pollinators are vulnerable to insecticides @ -when they travel, the pesticides come in contact with other organisms and can cause harm -can get into soil, air water disrupt the balance of an ecosystem (kills non-pest organisms) chemicals cause harm to huamn Bioaccumulatio (synthetic chemicals can't be broken down)

Examples of current environmental toxicology issues *???

Toxins in surface water: Elk River, WV Toxins in household products --common household products, including baby products ----flame-retardant chemicals used in dozens of baby product -----car seats and diaper changing pads U mining in VA Camp Lejeune water contamination Chemicals in consumer products --ex: Toxins in other common household products, including baby products (car seats and diaper changing pads) Toxins in surface water --Elk River, WV TB 4 main types of environmental hazards: 1) Physical: arise from processes that occur naturally in our environment and pose risks to human life or health. Ex: Sun UV rays --Excessive exposure increases the risk of skin cancer 2) Chemical 3) Biological 4) Cultural . Chemical hazards (b) include both synthetic and natural chemicals. Much of our exposure comes from pesticides and household chemical products. Biological hazards (c) include diseases and the organisms that transmit them. Some mosquitoes are vectors for pathogenic microbes, including those that cause malaria. Cultural or lifestyle hazards (d) include the behavioral decisions we make, as well as the socioeconomic constraints forced on us. Smoking is a lifestyle choice that raises one's risk of lung cancer and other diseases. Selected Environmental Hazards 1) Outdoor Air • Chemicals from automotive exhaust • Chemicals from industrial pollution • Photochemical smog (p. 465) • Pesticide drift • Dust and particulate matter 2) Water • Pesticide and herbicide runoff • Nitrates and fertilizer runoff • Mercury, arsenic, and other heavy metals in groundwater and surface water 3) Food • Natural toxins • Pesticide and herbicide residues 4) Indoors • Smoking and secondhand smoke • Radon • Asbestos • Lead in paint and pipes • Toxicants in plastics and consumer products (bisphenol A, PBDEs, phthalates, etc.) • Toxic compounds produced by mold • Dust and particulate matter

- Hubbert's peak (U.S.)

U.S. oil production already PEAKED • Hubbert's peak: the peak in U.S. oil production § Geologist M. King Hubbert guessed that oil production would peak around 1970. -he was right -U.S. oil peaked in 1970 --declined through years of low prices and new drilling technologies TB "peak in production of crude oil in U.S. which occurred in 1970 like Hubbert guessed

Solution mining $

Use: -when the resource is soluble (it can be dissolved in a liquid) -when it's very deep. Consists of: 1)Pumping acid/water into a deep hole to dissolve the resources. 2) Brine (water containing dissolved salts and target minerals) is then brought to the surface, where water evaporates, leaving the bring behind. Examples: -Salt, -lithium, -boron, - bromine, -magnesium -potassium Cons: groundwater contamination --("contamination of aquifers with acids, heavy metals, or uranium leached from the rock") TB less area at the surface is disturbed.

Strip mining and effects

Used when resources occur in shallow, horizontal deposits near the surface. -Coal, -OIL SANDS -gravel Cons: -Destroys natural communities --destroys ecosystems --"By completely removing vegetative cover and nutrient-rich topsoil", -Increases soil erosion ---soil from refill can easily go away Acid mine drainage H2SO4 --sulfide minerals form sulfuric acid --as acid runs off, it flow into waterways and "leaches toxic =metals from the rocks" -• Results in lots of overburden (soil and rock that is removed by heavy machinery) TB used when resource occurs in shallow horizontal deposits near the surface - layers of surface soil and rock are removed from large areas to expose the resource

- Open-pit mining and effects

When a resource is evenly distributed throughout a rock, or when the earth is unsuitable for tunneling -Used for: - Coal and coal sands - Clay, gravel, sand - Stone- limestone, granite, marble, slate ("Quarries") - Minerals, including Copper, Iron, -Largest open pit copper mine in the world; Chuquicamata, Chile -Cons: • Same habitat degradation stuff as other forms of mining, but also... • Abandoned mine pits often fill with very toxic water TB "essentially involves digging a gigantic hole and removing the desired ore, along with waste rock that surrounds the ore." Cons: -huge size of these mines means that the degree of habitat loss and aesthetic degradation is big -chemical contamination from acid drainage --(as water runs off the waste heaps or collects in the pit. -when mining is done, abandoned pits fill up with groundwater, which becomes toxic (as water and oxygen react with sulfides from the ore and produce sulfuric acid). -Acidic water from the pit can harm wildlife and can percolate into aquifers and spread through the region.

Subsurface mining and effects

When coal seams are not horizontal, subsurface mining is used. Accesses deep pockets of a mineral through tunnels and shafts 2.5 Zinc, lead, nickel, tin, gold, diamonds, phosphate, salt, coal. Cons: Most dangerous type of mining! - Dynamite blasts, collapsed tunnels, natural gas explosions (-Immediate deaths) - Toxic fumes and coal dust --Chronic illnesses --respitory disease (black lung disease) Risk of sinkholes => damages roads, homes, other infrastructure -Acid drainage, polluted groundwater ---"toxic leachate can make its way from mining sites to nearby ground- water. Abandoned mine sites can continue polluting ground- water long after mining has ceased." TB When a resource occurs in concentrated pockets or seams deep underground, and the earth allows for safe tunneling -shafts are excavated deep into the ground, and networks of tunnels are dug or blasted out to follow deposits of the mineral -- remove the resource systematically and ship it to the surface.

Endocrine disruptors

affect the endocrine (hormone) system • Hormones stimulate growth, development, sexual maturity • Synthetic chemicals - Block hormones - Mimic hormones -In mammals and birds, DDT affects health mainly by mimicking reproductive hormones, resulting in -decreased sperm production -female reproductive problems -and less viable offspring. -Detrimental effects of atrazine FROGS --"disrupt hormones by inducing production of aromatase, an enzyme that converts testosterone to estrogen." --ex: "male frogs raised in water containing very low doses of the herbicide became feminized and hermaphroditic, developing both testes and ovaries Ex: infertility in male pesticide workers Prevalent endocrine disruptors: -• Bisphenol A (BPA) and phthalates • Bind to estrogen receptors and that disrupt hormones • Sources: plastics, household products • Effects: Birth defects, cancer, reproductive effects in animals...same in humans?? - Found in the bodies of everyone in the U.S. • Polybrominated diphenyl ethers (PBDEs) = has fire- retardent properties - Used in computers, televisions, plastics, and furniture - Persist and accumulate in living tissue - Interferes with thyroid hormones - Concentrations in breast milk have increased exponentially between 1972 and 1997. - Banned in Europe (still ok in USA) TB -affect an animal's endocrine system by blocking the action of hormones or accelerating their breakdown. Others are so similar to certain hormones in their molecular structure and chemistry that they "mimic" the hormone - by interacting with receptor molecules just as the actual hormone would -causing the cell to react like it encountered the hormone. Ex: 1) Bisphenol A -chemical that appear to mimic the female sex hormone estrogen and bind to estrogen receptors. 2)Phthalates -Many plastic products also contain another class of hormone-disrupting chemical, called phthalates. -Used to soften plastics and enhance fragrances, Sources: -children's toys -perfumes -cosmetics -CAUSE: birth defects, breast cancer, reduced sperm counts, and other reproductive effects

Pesticides

any chemical used to kill unwanted weeds and insects (includes herbicides and insecticides) • Targeted, manual spraying is labor-intensive! • Easier to just spray everything (Row spraying vs Manual application) TB -most farmers have turned to chemicals to suppress pests and weeds. In that time we have developed thousands of chemicals to kill insects -Such poisons are collectively termed pesticides. @ -more food -more profit -less disease bc killed pest that transmit them (malaria)

Neurotoxins

assault the nervous system -In insects, DDT causes nerves to continuously fire, leading to continuous spasms and death. TB Effects can include: -slurred speech, -loss of muscle control, -sudden fits of laughter, - death. EX: -venoms produced by animals such as snakes and stinging insects, -heavy metals such as lead and mercury, pesticides, -some chemical weapons developed for use in war

Mutagens

cause DNA mutations, -which can cause cancer TB $ are substances that cause genetic mutations in the DNA of organisms (p. 29). -most mutations have little or no effect, some can lead to severe problems, --including cancer and other disorders. -If mutations occur in an individu- al's sperm or egg cells, then the individual's offspring suffer the effects.

Teratogens

cause birth defects in embryos TB -chemicals that cause harm to the unborn

• Carcinogens:

cause cancer - Hard to identify because of the long lag time between exposure and onset of cancer TB "substances or types of radiation that cause cancer" . -cancer= malignant cells grow uncontrollably, creating tumors, damage ing the body, often death leading to death.

Environmental Toxicology

deals with toxic substances that come from or are discharged into the environment • ~85,000 synthetic chemicals! • Every human carries traces of industrial chemicals! • The U.S. makes or imports 250 lb of chemicals for every person in the country!!

Global climate change

describes trends and variations in Earth's climate, including temperature, precipitation, & storm frequency

How are FF created

formed from ancient organic matter Fossil fuels begin to form when organisms die and end up in oxygen-poor conditions. Can occur when: 1a)Ancient Swamp: Woody terrestrial vegetation dies and falls into swamp --ex: trees fall into lakes and are buried by sediment 1) Ancient Ocean: when phytoplankton/zooplankton/other marine organism die, sink to seafloor are buried ~down arrow~ Organic matter that undergoes slow anaerobic decomposition deep under sediments forms kerogen. 2a) Organic matter from woody land plants is partly decomposed by microbes under accumulating sediments; kerogen forms 2b) Organic matter from soft-bodied sea life is partly decomposed by microbes under accumulating sediments; some carbon bonds are broken; kerogen forms ~down arrow (Heat and pressure deep underground alter kerogen) 3a) COAL formed from kerogen -Coal results when plant matter is compacted so tightly that there is little decomposition 3b) action of geothermal heating on kerogen may create NATURAL GAS AND CRUDE OIL -Swampy areas form fossil fuels because sediment builds up but doesn't break down because swamp sediment is generally anaerobic (low in O2). --Carboniferous (300 mya)? TB -formed from the tissues of organisms -energy these fuels contain came originally from the sun and was converted to chemical-bond energy by photosynthesis. -The chemical energy in these organisms' tissues then became concentrated as these tissues decomposed and their hydrocarbon com- pounds were altered and compressed Fossil fuels are produced only when organic material is broken down in an ANAEROBIC environment --(one that has little or no oxy- gen). EX: -bottoms of lakes, -swamps, -shallow seas. Over millions of years, organic matter that accumulates at the bottoms of such water bodies may be converted into crude oil, natural gas, or coal, depending on (1) the chemical composition of the material, (2) the temperatures and pressures to which it is subjected, (3) the presence or absence of anaerobic decomposers, and (4) the passage of time.

Global peak oil???

global production is peaking -Discoveries of new oil fields peaked 30 years ago, and since then we have been extracting and consuming more oil than we have been discovering. TB -predict that at some point in the coming decade, production will begin to decline

Crop Rotation

growing different crops from one season/year to the next - Returns nutrients to soil - Prevents erosion ("Minimizes erosion from letting fields lie fallow) @ Different crops use different soil nutrients, and by changing crops from time to time, the soil has a chance to recharge its nutrient load. - Reduces pests (" if an insect is adapted to feed and lay eggs on one crop, planting a different type of crop will leave its offspring with nothing to eat") TB -Can break cycles of disease associated with continuous cropping.

Acute exposure

high exposure for short period of time - Examples: ingestion, oil spills, nuclear accident TB -easier to recognize -often come from discrete events -accidential ingenestion, -oil spill, a chemical spill, or a nuclear accident. -

Desertification Effects

is the loss of more than 10% of soil productivity in arid areas due to such factors as erosion, soil compaction, overgrazing, and forest removal Desertification-more than 10% of productivity is lost ("form of land degration" as a RESULTS FROM -Erosion (most), Soil compaction -Deforestation, Overgrazing - Drought, salinization, water depletion - Climate change ("alters rainfall patterns, making more dry") • Most prone areas: - Arid - Semiarid Effect -gigantic dust storms -expand/create new desert TB Much of the world's population lives and farms in drylands, arid and semi-arid environments -percipation in these regions=low SO DRYLANDS PRONE -most results from WIND AND WATER EROSION $ - Everywhere, soil degradation forces ranchers to crowd onto poorer land and farmers to reduce the fallow periods during which land lies unplanted and can regain nutrients. --(both further worsen soil degradiation ) - Effects: -expand/create new desert -endangers the food supply or well-being of 1 billion people -cost billions of dollars -gigantic dust storms @ Defintion": conversion of habitable and fertile land to uninhabitable desert. Cause: decrease in vegetation -plants are removed, the soil will be exposed to the sun and will dry out more quickly. -The roots of plants often help hold soil in place. -If plants are removed, the soil will have nothing protecting it --(more susceptible to erosion by wind). -TOP SOIL BLOWN AWAY, reduce land fertility -Eventually, the land will become so dry and devoid of vegetation that it will be classified as a desert. -Overgrazing and defortestiatoin: remove or damage the vegetation that is protecting the land and keeping it moist and fertile. -

Toxicology

is the study of chemical hazard TB Toxicology: the science that examines the effects of poisonous substances on humans and other organism -toxicologist compare substances to determine TOXICITY: the degree of harm a chemical substance can inflict -TOXICANT=Toxic/poison --but any chemical substance can have negative impact if exposed enough --toxicity doe ends not only on chemical properties, but also quantity

Monoculture $?

large expanses of a single crop --(#result of green revolution ?) Pros of monoculture - Efficient planting and harvesting - Increased yields Cons of monoculture - Devastates biodiversity - Susceptible to disease and pests ---Ex of pest: armyworms TB "Monocultures improve the efficiency of planting and harvesting but are susceptible to outbreaks of pests." Defintion: "The planting of crops in monocultures, large expanses of single crop types" (p. 218; Figure 10.7), - makes planting and harvesting more efficient and thereby increases output. -Reduce biodiversity over large areas -- because many fewer wild organisms are able to live in monocultures than in native habitats or in traditional small- scale polycultures. -Moreover, when all plants in a field are genetically similar, as in monocultures, all are equally suscep- tible to viral diseases, fungal pathogens, or insect pests that can spread quickly from plant to plant. -- For this reason, mono- cultures bring risks of catastrophic failure. -contribute to a narrowing of the human diet. Globally, 90% of the food we consume now comes from just 15 crop species and eight livestock species—a drastic reduction in diversity from earlier times. Such dietary restric- tion carries nutritional risks.

Chronic exposure

low exposure for long periods of time - Hard to detect and diagnose - Affects organs gradually - Cause and effect may not be easily apparent (bc long time period) TB -more common than acute -smoking, alcohol -pesticide in good/drink

Allergens

over activate the immune system -"causing an immune response when one is not necessary" TB -increase in asthma

Intercropping

planting different crops in alternating bands "or other spatially mixed arrangements" - Increases ground cover - Replenishes soil - Decreases pests and disease - Minimize erosion " by providing more ground cover than does a single crop" TB "when a nitrogen-fixing legume is used, replenishes the soil"

Conservation tillage

reduces the amount of tilling - Leaves at least 30% of crop residues in the field - most intensive form is No-till farming. ---it disturbs the soil even less TB "describes an array of approaches that reduce the amount of tilling relative to conventional farming; -one common definition: any method of limited tilling that leaves more than 30% of crop residue covering the soil after harvest. No-till farming "Farmers practice no-till farming with a no-till drill. The drill 1 cuts a furrow through the soil surface, 2 drops in a seed, and 3 closes the furrow over the seed." -can help restore soil quality.

- Manipulative experiments

show causation • Animals are used as test subjects • Substances that harm rats and mice (other mammals) probably harm • LD50: the dose needed to kill 50% of a population of test organisms • But some people object to animal tests (unethical) --"but enables scientific and medical advances that would be impossible or far more difficult otherwise" • New techniques, like human cell cultures may replace some live-animal testing TB Still, new techniques (with human cell cultures, bacteria, or tissue from chicken eggs) are being devised that may soon replace some live-animal testing. Standard method of testing with lab animals: -DOSE-RESPONSE. -- quantify the toxicity of a substance by measuring the strength of its effects or the number of animals affected at different doses. --dose=the amount of substance the test animal receives --response =the type or magnitude of negative effects the animal exhibits as a result. --normally quantified by measuring the proportion of animals exhibiting negative a substance's toxicity: the amount of the substance it takes to kill half the population of study animals used. -This lethal dose for 50% of individuals is termed the LD50 . -High LD = low toxicity -Low LD50 = high toxicity.

Agriculture

the practice of raising crops and livestock for human use and consumption

Climate change PP

xxx

- Greenhouse gas emissions

§ Carbon dioxide (CO2) has biggest environmental impact of fossil fuel use - bc leads 2 global climate change § This and other greenhouse gases (GHGs) lead to changes in global climate TB Burn fossil fuels= fluxes in Earth's carbon cycle --We take carbon that has been retired into a long-term reservoir underground and release it into the air. --This occurs as carbon from the hydrocarbon molecules of fossil fuels unites with oxygen from the atmosphere during combustion, PRODUCING CARBON DIOXIDE (CO2). -Carbon dioxide is a greenhouse gas -CO2 released from fossil fuel combustion warms our planet and drives CHANGES IN GLOBAL CLIMATE -methane is another GHG that causes climate warming.

• Summary of downsides of fossil fuels

§ Non-renewable => unsustainable § Mining & other extraction techniques harm environment and human health (...economy) § Emissions from burning are harmful 2 environment and human health (...economy)

Coal effect on ecosystem HG

• Coal contains many impurities, including -sulfur, -mercury, -arsenic, -other trace metals • "Clean coal" technologies help reduce sulfur, but other impurities remain. Mercury (Hg) pollution from coal-fired power plants is still a large problem TB Clean coal technologies =to techniques, equipment, and approaches that try 2 remove chemical contaminants during the process of generating electricity from coal. ( technologies are various types of scrubbers, devices that chemically convert or physically remove pollutants) -POLLUTION -burning of coal causes the release of pollutants into the atmosphere that fall back to Earth as precipitation (acid rain) -extraction and transporting of fossil fuels can be harmful @

Fertilizers (types) - pros and cons

• Fertilizers: substances containing essential nutrients (esp. Nitrogen and Phosphorous) • Inorganic fertilizers: mined or (synthetically) manufactured mineral supplements • Organic fertilizers: the remains or wastes of organisms --"(animal manure; crop residues; fresh vegetation (green manure)) ----organic matter that improves soil structure, nutrient retention, and water-retaining capacity --expensive" Pros: -boost yields Cons: -air & water pollution -unsustainable -expensive TB -we add fertilizer to enhance nutrient-limited soils INORGANIC: --more susceptible to leaching and runoff --more readily contaminate groundwater supplies. EX of harm: nitrogen and phosphorus runoff from farms and other sources in the Mississippi River basin spurs phytoplankton blooms in the Gulf of Mexico and creates an oxygen-depleted "dead zone" that kills fish and shrimp -EUTROPICATION occurs at rivers, lakes, and ponds -Nitrates readily leach through soil and contaminate groundwater, and components of some nitrogen fertilizers can evaporate into the air. -results of these processes: unnatural amounts of nitrates and phosphates spread through ecosystems ---human health risks, including cancer and methe- moglobinemia, or blue-baby syndrome, which can asphyxiate and kill infants. -Human inputs of nitrogen have changed the nitrogen cycle --account for one-half the total nitrogen flux on Earth. quote from textbook: "Overapplication of fertilizers has impacts beyond the farm field, because nutrients not taken up by plants end up elsewhere. Nitrates can leach into aquifers and contaminate drinking water. Runoff of phosphates and nitrogen compounds can alter the ecology of waterways through eutrophication. Compounds such as nitrogen oxides may pollute the air."

Soil Erosion as a global issue

• Humans are the primary cause of erosion • It is occurring at unnaturally high rates • In Africa, erosion could reduce crop yields by half over the next 40 years TB -we have accelerated erosion at unnaturally high rates -human activities move over 10 times more soul than all natural processes -Erosion rates from conventional agriculture are MUCH HIGHER than rates: ----- in fields farmed under conservation tillage, -----in areas covered by native vegetation -----averaged over the geologic record. -223 (9) Solution: -lands farmed under conservation approaches erodes less than conventional

Sustainability of mined resources*

• Minerals are non-renewable resources. --so supplies of metals are limited • Rarer metals are becoming harder to find and extract. - Example: not much left of: • Indium (LCD screens) ~32 year supply ("ex: LCD screen" • Tantalum (cell phones, etc) ~60 year supply TB - they form far more slowly than we use them - if we continue to mine them, they will eventually be depleted -As minerals become scarcer, demand for them increases and price rises. -Higher market prices make it more profitable for companies to mine the resource, so they become willing to spend more to reach further deposits that were not economically worthwhile originally.

History of agriculture ??

• Substance farming - ~12,000 yrs • Industrial agriculture - Industrial Revolution TB -For thousands of years, the work of cultivating, harvesting, storing, and distributing crops was performed by human and animal muscle power, along with hand tools and simple machines—an approach known as traditional agriculture. -in SUBSITENCE agriculture (oldest form of traditional agriculture) --,farming families produce only enough food for themselves. --As farmers began integrating into market economies and producing excess food to sell, they started using teams of animals for labor and significant quantities of irrigation water and fertilizer. -INDUSTRIAL REVOLUTION -introduced large-scale mechanization and fossil fuel combustion to agriculture and industry. -Farmers replaced horses and oxen with machinery that provided faster/more powerful means of cultivating, harvesting, transporting, and processing crops. -boosted yields by intensifying irrigation and by introducing synthetic fertilizers. -advent of chemical pesticides reduced competition from weeds and herbivory by crop pests. -machinery created a need for highly organized approaches to farming, leading us to plant vast areas with single crops in straight orderly rows. --Such MONOCULTURES ("one type") are distinct from the polycultures ("many types") typical of traditional agriculture, -$Today, industrial agriculture occupies over 25% of the world's cropland -Industrial agriculture spread from developed nations to developing nations with the advent of the GREEN REVOLUTION --Intensive cultivation of MONOCULTURES using pesticides, irrigation, and chemical fertilizers has many consequences, and can degrade the integrity of SOIL, the very foundation of our terrestrial food supply.

Fate of toxins in the environment

• Toxins can degrade quickly and become harmless • But some toxins remain unaltered and persist for decades • Rates of degradation depend on the substance (chemistry), temperature, moisture, and sun exposure • Breakdown products may be more or less harmful than the original substance: - DDT degrades into DDE, which is also highly persistent and toxic - Malathion degrades to malaoxon = even more toxins TB Air and water currents direct pollutants to the poles. In global distillation, 1) pollutants that evaporate and rise high into the atmosphere at lower latitudes 2) or are deposited in the ocean, are carried toward the poles by atmospheric currents of air and oceanic currents of water. 3) This process concentrates pollutants near the poles 4) causes elevated exposure to toxic substances in polar organisms . ex: Bt toxin (pp. 256, 262) used in biocontrol and genetically modified crops has a very short persistence time, whereas chemicals such as DDT and PCBs persist for decades. -Persistent synthetic chemicals exist in our environment today because we have designed them to persist. The synthetic chemicals used in plastics, for instance, are used precisely because they resist breakdown. Sooner or later, however, most toxicants degrade into simpler compounds called breakdown products. Often these are less harmful than the original sub- stance, but sometimes they are just as toxic as the original chemical, or more so. For instance, DDT breaks down into DDE, a highly persistent and toxic compound in its own right.

• Mining policy*** 646

• US policy still guided by GENERAL MINING ACT OF 1872 - Any company or person may mine on federal land open to mining ("gains the sole right to take minerals from the area") - Once purchased (at $5/ acre!), no profit goes to public ----gives valuable public resources away to private interests nearly for free -"until recently no restoration was required" • In 2007 and again in 2009, Congress tried to pass the Hardrock Mining and Reclamation Act. Hardrock Mining and Reclamation Act would have: • Protected national parks and monument from mining • Established environmental standards: o Protect water supplies o Fish and wildlife protection o Adequate reclamation • Implemented fiscal reforms o BLM estimates that $982 million in hard rock minerals were taken from public lands in 2000. Taxpayers got nothing for this. o Reforms would include 4% royalties for existing mines, 8% for new mines • Created funds to clean up abandoned mines and assist impacted communities • Required better industry oversight. TB -The general Mining act of 1872 encourages people and companies to prospect for minerals on federally owned land by allowing any U.S. citizen or any com- pany with permission to do business in the U.S. to stake a claim on any plot of public land open to mining. -The person or company owning the claim gains the sole right to take minerals from the area. -law requires no payments of any kind to the public, and until recently no restoration of the land after mining was required. The General Mining Act of 1872 was enacted partly in response to the chaos of the California Gold Rush and other 646 episodes, and it was designed to bring some order to mining