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Chapter 6-11 dicussing environemtal impacts, Lecture notes of Environmental Science

Water, Fossil Fuels, Soil Types

Typology: Lecture notes

2022/2023

Uploaded on 10/30/2023

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Chapter 6
California perpetual drought- naturally happens
Humans need freshwater for a variety of reasons, including
agricultural, sanitation, industry, and drinking
- Humans use usually requires water storage (dams) and
diversion (canals)
- There is a growing mismatch between human needs and existing
water supplies
- 40% of human population lacks freshwater fir sanitation
- Using freshwater can harm aquatic ecosystems which
themselves provide valuable ecosystem services
- Tulare lake is no longer existing replaced with crops
Hydrologic cycle- study of water, the water cycle
Distribution of Earth’s water- 3% of all water is freshwater but
like 1% is usable in the sense of surface water
- Easily accessible freshwater supplies, lakes, and rivers are
just 0.3% of the total water
Ground is an important Resource
Groundwater, such as that used in California to help alleviate
drought, exists in geological structures called aquifers
- Amount of water is an aquifer is the balance between
infiltration and losses of groundwater to the surface
- Water table is the uppermost level of groundwater
- The groundwater is help in pores allied the saturated zone
- Above the water table is the unsaturated zone where there is
no water
Tradewinds- push storms across different lands from the ocean
Water Issues
- Daily water needs- 50 L per day or 13 gallons each day
Human use of freshwater; half goes to the ocean, third goes to
accessible runoff, and a sixth is remote runoff
Arid Regions: one third of Earth’s surface with one-fifth of the
population
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Chapter 6 California perpetual drought- naturally happens Humans need freshwater for a variety of reasons, including agricultural, sanitation, industry, and drinking

  • Humans use usually requires water storage (dams) and diversion (canals)
  • There is a growing mismatch between human needs and existing water supplies
  • 40% of human population lacks freshwater fir sanitation
  • Using freshwater can harm aquatic ecosystems which themselves provide valuable ecosystem services
  • Tulare lake is no longer existing replaced with crops Hydrologic cycle- study of water, the water cycle Distribution of Earth’s water- 3% of all water is freshwater but like 1% is usable in the sense of surface water
  • Easily accessible freshwater supplies, lakes, and rivers are just 0.3% of the total water Ground is an important Resource Groundwater, such as that used in California to help alleviate drought, exists in geological structures called aquifers
  • Amount of water is an aquifer is the balance between infiltration and losses of groundwater to the surface
  • Water table is the uppermost level of groundwater
  • The groundwater is help in pores allied the saturated zone
  • Above the water table is the unsaturated zone where there is no water Tradewinds- push storms across different lands from the ocean Water Issues
  • Daily water needs- 50 L per day or 13 gallons each day Human use of freshwater; half goes to the ocean, third goes to accessible runoff, and a sixth is remote runoff Arid Regions: one third of Earth’s surface with one-fifth of the population

Droughts Have Regional effects

  • Droughts: extended dry period with no precipitation and water supplies sometimes need to be rationed Floods can also cause problems with water management if they damage infrastructure The Colorado Basin: 265 dams
  • 1.5 million hectares (3.7 million acres) of irrigated farmland
  • 25 million people depend upon the river The Colorado is Over Appropriated There is more demand for water than there is water in the Colorado Basin
  • Water use is governed by laws and treaties
  • The river no longer reaches the sea Conflict over limited water will only increase as the population grows and climate changes One-quarter of Earth’s population relies on groundwater, but it is usually used faster than it is replenished
  • Depth to groundwater is increasing
  • Oases are drying
  • The land subsides Ogallala Aquifer - groundwater depletion in the Great Plain threatens agriculture Managing water supplies Dams have wide-ranging ecological effects
  • Threatens biodiversity
  • Trap sediment that supplies nutrients downstream
  • Altered temperature patterns below the dam as cold water released
  • Prevent fish migration Flooding and Biodiversity Although floods can harm crops and damage buildings, flooding is an important process that maintains floodplain biodiversity. Floods: get notes he went to fast lol
  • 16,000 desalination plants globally produce about 1% if human needs
  • Mostly limited to wealthy countries where water is very scarce Distillation : oldest and most expensive Reverse Osmosis This method is less expensive, but it can also produces concentrated brine that can harm the environment when it is disposed
  • The Tampa Bay desalination plant uses the method
  • Produces 10% of the city’s freshwater supply
  • Brine is diluted… he went too fast again Wetland restoration Wetland reduce sedimentation, purify water, and provide habitat Kissimmee River Restoration The Kissimmee River was straightened in the 1940s to reduce flooding
  • Straightening cut off the river from the floodplain, and bird population plummeted
  • Organic matter deposited in the channel reduced oxygen concentrations and harmed fish populations
  • Re-establish floodplain connectivity has increased habitat for fish and birds Questions Which category is the largest for human daily usage? D. sanitation Which country is the biggest per capita use of water? D. usa Which of the following describe the ground layers above the groundwater? unsaturated zone Which of the following describe the uppermost level of the groundwater Water Table

Which of the following describes an area of land that collects precipitation that flows into aquifers and rivers? Watershed Which is the largest reservoir of freshwater on Earth Glaciers and ice caps What does tertiary water treatment remove? All of the above Chapter 7 Sustaining Terrestrial Resources Global Primary Productivity Note that primary production rates closely match Earth’s Biomes

  • Tropical forests are most productive
  • Deserts and tundra are the least productive Terrestrial Harvest System Harvest systems are subject to the same environmental factors as are biomes
  • Farming occurs in temperate grasslands, temperate forests, and mediterranean biomes
  • Ranching occurs in many places, but is is only activity that can take place in arid lands or tundra
  • Forestry occurs where trees can grow, but farming is difficult after forest removal in tropical and coniferous biomes Soils are complex
  • Soil structure supports biodiversity within soils, and these organisms can affect soil development through their activities
  • Nitrogen in the backbone of making everything Climate effects on Soil Climate is another major contributor to soil structure that affects:
  • Organic matter content, Depth, Color, Fertility

- Mineral soil, organic matter, and inorganic nutrients Monocultures requires tillage which exposes soil to wind and water erosions Overgrazing

  • Semi-arid rangelands are susceptible to erosion because of low productivity
  • Removal of plant matter bt livestock express soil to erosion Desertification
  • Semiarid rangeland becomes permanently less productive when overgrazed Deforestation: affects all forested zones worldwide
  • Countries is S asia have lost between one-fifth and one-half of their forest cover in recent decades
  • Russia lost an area the size of MOntana over 5 yrs. Earlier this century
  • Forest often clear cut (= not a tree left standing) Soil Loss from Logging Vegetation removal from logging ( finish notes he skipped) Fire Suppression
  • Wildfires are natural and historically burned with higher frequency but lower intensity Fire suppression
  • Increases tree densities and thus fallen wood/ branches in forests Catastrophic fires
  • Soil losses extreme after such events Irrigation Irrigation accounts for 70% of water withdrawals globally and threatens freshwater biodiversity
  • Flood irrigation gravity fed and inexpensive but wastes a lot of water
  • Sprinklers: less water but equipment is costly
  • Drip irrigation: uses least amount of water but equipment very costly Soil Salinization
  • Low amounts of natural salts in irrigation water remain on the field after evaporation, causing salt contect to build up
  • Eventually soil fertility is lost and crops will not grow Pollution from Intensive Agriculture Cost of Pesticides: protect us from 40 billion in crop value Pest Outbreaks and Resistance Predators of pests are generally more susceptible to pesticides
  • When their populations are reduced, a pest outbreak can occur that requires additional pesticide Pesticides use rapidly drive natural selection
  • When resistant individuals survive pesticides application, their offspring will also be resistant Genetically Modified Crops
  • Gm crops; engineered for a particular purpose like improved nutrition or disease resistance
  • Engineering usually adds gene to the crops dna
  • Transgenic crops have genes from the other organisms added
  • Bt corn had bacterium gene inserted so it produces a compound that kill insects that eat the corn Health Benefit of GM crops Golden rich is engineered to produce vitamin A
  • Vitamin a deficiency can cause premature blindness
  • Vitamin a deficiency is more widespread in the developing world
  • Golden rich as 23x times the vitamin rice and wild rice Crop Diversity Can Improve Yield
  • Mixed plantings of rice reduced fungal infection Managing Agricultural Tillage

Questions Which of the following agricultural technique alter crop species a. Crop rotation Soil erosion in the US removes the most of which of the following components of soil b. Mineral soil Intensive agricultural generates which of the following types of pollution D. all of the above Use of pesticides that involves tolerance is only some members of a pest species is called: ( who is left) B. pesticides resistance Which of the plowing plowing techniques leaves crop residues on the field after harvest B. no till farming Which region of the world is most dependent on irrigation for successful crops B. northern africa Over Irrigation of agricultural fields lead to D. saline soils What does successful IPM required D. all of the above Which of the following involves planting susceptible crops to reduce pesticide resistance C. refuge technique The low productivity of tundra and desert biomes favor ____ as a way of life A. nomadic animal herding Chapter 8 Sustaining Aquatic Resources

Cod fishery Collapse The bottom dwelling atlantic cod is top predator that was prizes as a protein sources

  • Cold fishery lasted nearly 500 yrs
  • Peak harvest was in the 1960s
  • In 1992 the fishery had dropped to 1% od irs historic level
  • Today the fisher is still closed and shows just little sign of recovery
  • 68 fish stocks are currently in an overfished status, and these declines threatened marine food webs Fishing Methods
  • Subsistence fishing: personal nutrition needs
  • Commercial fishing: small scale minimal gear or industrial major gear
  • Bycatch a major issue
  • industrial : travelers, long line, gillnetting, pot-traps
  • Recreational, aquaculture: fish farming
  • 90 million metric tons from commercial fishing
  • 60 million metric tons come from agriculture Trawler Fishing — ver bad Oceanic circulation The oceanic food web depends on patterns of primary production, which are affected by nutrient distribution in the ocean Wind creates current The Euphotic Zone: upper 200 m of water supporting photosynthesis
  • Organic matter produced here that dies sinks below the euphotic zone and decomposes
  • Decomposition releases nutrients into the water column
  • Warmer because it receives light, so the ocean does not mix vertically Major Marine Environments The most productive fishing areas are in upwelling zones
  • Wind blow warm nutrient-poor surface waters away in an ocean current
  • This brings nutrient-rich cold water to the surface
  • In the columbia river system, 45% of spawning habitat is not accessible
  • Mitigating dams with fish ladders still forces salmon to navigate lakes instead of streams
  • Once they return to their habitat, it is degraded bt land development
  • Most columbia river stocks are threatened or endangered, and Klamath stocks are listed as a threat Klamath River Salmon Dam construction on the Klamath began in 1918 and restricted access to habitat
  • Ultimately, 600 miles of spawning streams were isolated
  • Water withdrew for irrigation caused reduction flows
  • Algae blooms steal nutrient runoff Aquacultural: controlled, intensive farming of aquatic resources
  • As fish stocks decline, the seafood industry turned to aquaculture to sustain production
  • Aquaculture can be performed in marine, brackish or freshwater environments Problems with Aquaculture
  • Escaped fish or crustaceans can become invasive, asian carpal or hybridize with local species atlantic salmon raised in the pacific
  • Concentrating fish and supplementing food increases the risk of nutrient pollution and algae blooms
  • Clearing mangrove forests for shrimp farming degrades local biodiversity and increases flood risk during storms
  • Growing fish at a high density can increase parasites and pathogens which can spread to native fish
  • Supplemental feed for aquaculture must be harvested from the wild, depleting fish from other food webs Solutions The moratorium on whaling shows that whale stocks can recover
  • Right whales have been increasing 708% annually
  • Gray whales are at their estimated historic population size
  • Humpback whales have recovered to pre whaling numbers
  • Iceland and JApan have a long history of whaling and they hunt some whales every year Fishing restrictions and regulations can help ensure sustainable fishing
  • Size regulations protect the reproducing adults and ensure that enough young survive
  • Fines or loss of commercial license if regulations are belated
  • Gear restrictions reduce bycatch, which is not commercially viable but still affects food webs
  • Changing what gear is legal off the coast of southern California allowed other predatory fish to recover Cooperative Management
  • Managing the resources in partnership brings community together for a common interest to sustain the fishery
  • The bristol bay salmon fisher is managed by fishers, community members, and scientists Catch Shares ITQs grant a transferable right to a portion of the catch to a person, cooperative, or a community
  • Individual transferable quotas (ITQs) allocate the right to a share of the catch to the fisher Ecosystem Services – not a solution but what we gain from the solutions Salt marshes, kelp forests, mangrove forests, and riparian wetlands High diversity means that the system is buffered from climatic, ocean, and landscape disturbances - Sometimes one subpopulation is more abundant, sometimes another one is
  • collectively the system

Crude Oil Refining

  • Refining oil separates the oil into its components = heating it
  • Crude oil is heated until it evaporates **Petroleum Reserves
  • Like coal petroleum is not equally distributed geographically**
  • 90% worlds reserves are controlled by 15 countries
  • Most found in the middle east Natural Gas
  • Methane, ethane, propane, and buthane Formation and Use of Natural Gas Natural gas migrates through porous rock until trapped by a cap rock
  • Once considered a waste product
  • Now widely used
  • About 25% if U.s energy use
  • Natural gas reserves, russian, iran and qatar have over half of all known reserves Thus fossil fuels may be distinguished by solid, liquid, and gaseous forms Electricity Generation Is useful form of energy because it can be transmitted long distances from site production
  • Electricity is the flow of electrons
  • Produced with generator composed of a magnet and conductor
  • Spinning conductor in the magnetic field produces a flow of electrons
  • It takes fuel to spin the conductor Nuclear reactions Nuclear Reserves
  • 15 countries have 97% if reserves
  • Us is the largest nuclear energy producer Largest energy consumers- US, European Union, and hightest china

Per Capita energy Use

  • World’s demand for energy is expected to increase 35% due to economic growth in developing countries Coal mining
  • When overburden (rock above coal) is took thick sub surfacing mining can be used to remove coal
  • When overburden, not too thick, it can be removed
  • Strip mining Mountaintop removal one of the most destructive coal mining practices Coal sludge and fly ash
  • Sludge ponds can be overfilled contaminating water Mining Oil Sands/Tar Sands Tar sands contain a hydrocarbon called bitumen
  • They either strip mined from open pits or heated so they flow to the surface
  • They are expensive to mind so they are economical only when oil prices are high Fracking
  • fracking fluid,sand, chemicals are injected under high pressure to fracture rocks
  • Sand keeps the fracture open and the oil or gas moves to the place to be pumped
  • Can contaminate drinking water supplies
  • Can cause earthquakes and deep well injection of wastewater from the oil industry Three mile island nuclear accident
  • Stuck valve caused the loss of coolant
  • The confinement structure contained the partial meltdown
  • The accident took 14 years to clean up at a cost of 1 billion
  • A meltdown occurs when the reactor core becomes too hot Chernobyl nuclear accident

a. Coal sludge Which is the Fly ash Which of the following us Fracking Not considered a nuclear reactor disaster Deepwater horizon Chapter 10 Renewable Energy Growth in renewable energy

  • Adoption of renewable energy may stress the environment on different ways than widespread fossil fuel use
  • Installation of wind solar electrical capacity is increasing exponentially
  • Half of newly installed electric capacity is now renewable Concentrating Solar Power When solar heat is concentrated, it can boil water to make steam to drive a turbine
  • Central receiving system collect the heat at a central location
  • Parabolic troughs concentrate heat in liquid flowing through the piper
  • These systems are not economical with low fuel prices, but new systems are more efficient Wind Energy Historic uses of wind were use for grinding grain, milling lumber Solar heating creates winds Water Power, Hydroelectric power Hydrokinetic Power
  • Tides happen because of the gravity of the moon and sun
  • Gravitational pulling either raise or lowers the height of the water
  • At high tide water is retained in a basin to be released through a turbine at lower tide Geothermal Energy Heat comes from the decay of radioactive elements within Earth
  • Uses steam to turn a turbine Biofuels - Today, dung is commonly used for cooking as is wood - Other biofuels include plant oils and animal oils like blubber or tallow - Global use of biofuels is increasing exponentially because they are easy to use in transportation Ethanol Can be produced from the simple sugars of food crops
  • Corn and sugar
  • Same process as making beer or wine
  • Fermentation converts sugars into ethanol which can be used as fuel Biodiesel
  • Plant oils can be used to make diesel, soybeans, canola, and palm oil today
  • Algae are an experimental source of biodiesel
  • Very efficient at converting solar energy very high growth rate Solar Energy Has Environmental impact Still requires land clearing and habitat destruction Concentrating solar plants requires water for steam turbines and cooling Wildlife Loss from Wind Power
  • Altamont Pass wind Turbines killed 9,000 birds per year birds of prey Bat Mortality Bats appear to have most mortality at low wind velocity