Station 1: Earth Science Review!!
Earth is made of many layers.
- Crust: top layer; 2 types: oceanic & continental crust.
a. Oceanic crust: thickness of 4-7 km. heavy.
b. Continental crust: thickness of 20-40 km; less dense than oceanic crust, sits on top of it.
- Mantle: below crust; rocks are so hot they are liquid. We never drilled to mantle. Heat rises from here creating convection currents that splits the crust apart into plates.
- Core: middle of earth; composed of Nickel and Iron, hot, gives earth magnetic poles.
- Inner core: solid metal composed of iron. Gives earth its magnetic field.
- Outer core: surrounds inner, is liquid metal.
Plate tectonics is a theory of movement of Earth’s plates created by Alfred Wegener. It says the lithosphere (Earth’s crust and top of mantle) is moving 1-16 cm a year in all directions. The plates are hitting each other and moving away from each other.
Divergent Plates: Two plates are moving apart. When this occurs, magma rises from mantle to form new plate material (mountains, volcanoes). A Rift Valley/Ocean Trench can be formed when plates separate. This forms a deep valley in the ocean where rocks tend to be extremely weak. When the bottom of the ocean diverges, we call this sea floor spreading.
Station 3 Converging Plates
Convergent plates: Two plates are hitting each other; places where plates are destroyed.
a. Oceanic Plate hitting Continental Plate: Oceanic plates dive beneath continental plates as they collide because ocean plate is heavier. This is called subduction: the process of one plate moving under another plate.
b. Continental hitting Continental: Forms mountains like the Himalayas due to continental uplift.
Ocean vs Continental Convergence Continental vs Continental
Practice Questions:
1) The convergence of two continental plates would produce
Aisland arcsB rift valleysC folded mountains.D trenches
2) A rift valley is evidence of which kind of plate boundary?
A convergentB divergentC transformD uniform
Station 2: Food Chains!
Station 3: Biogeochemical Cycles
Station 4: Population Math Review!
1. Population Density:
Population = Population Density
Area
Example:
270,000,000 people = 29 people per sq. km in the US
9,166,605 sq. km
2. Finding Birth & Death Rates:
Births = Birth Rate
Total Population
Example:
23, 452_ = 0.25 = 2.5% = Birth Rate
942, 721
Births Per One Thousand
25 = 0.25 = 2.5% = Birth Rate
1000
Deaths= Death Rate
Total Population
17, 228= .018= 1.8%= Death Rate
942, 721
Deaths Per One Thousand
Deaths= Death Rate
Total Population
18= .018= 1.8% = Death Rate
1000
3. Finding Population Growth Rate:
Births-Deaths= r (Growth Rate)
Total Population
Example:
23, 452 - 17, 228= r = .0066 = .66%
942, 721
Station 5: Water Pollution Review
Clean water is extremely important. Water is polluted from agricultural runoff of sediment (erosion), agricultural runoff of nutrients (eutrophication), industrial discharge (wastewater), trash, and mining (they are the worst!!!) These pollutants enter the water from either a point source (specific polluter) or a non-point source (cannot determine the exact source).
Commonly tested items in the water are:
Parameter / General InformationDissolved Oxygen (DO) / Phytoplankton put oxygen in the water. A healthy level is at 8 ppm. Organisms, such as fish, remove DO from the water. When DO levels are low, mass fish kills occur.
pH / 0-6 = acid, 7 neutral, 8-14 base. Organisms in waterways can only tolerate limited pH ranges. When those are exceeded, the organisms die.
Temperature Change (ΔT) / AKA Thermal Pollution. Use a thermometer to measure. Organisms in waterways can only tolerate limited temperature ranges. When those are exceeded, the organisms die.
Fecal Coliform / Bacteria found in feces lumped into one giant category. If found in a waterway, indicates feces present in the water. Enhances detritivore populations to rob waterway of oxygen.
Biochemical Oxygen Demand (BOD) / How much oxygen is demanded by organisms that respire in a waterway. Usually measured over a 5 day period.
Nitrates / Often a limited nutrient in waterways. Causes cultural eutrophication when too much exists in a waterway. Placed in waterways often by fertilizer and feces runoff.
Total Phosphates / Often a limited nutrient in waterways. Causes cultural eutrophication when too much exists in a waterway. Placed in waterways often by fertilizer and feces runoff.
Turbidity or Total Suspended Solids (TSS) / A measure of suspended particles in the water. Too many suspended particles clouds the water and decreases photosynthesis, thus leading to decreased oxygen in the water. Sediments are the most common form of pollution.
Practice Question:
Which of the following is the most prevalent form of water pollution?
a) oxygen demanding wastes
b) pathogens
c) methylated mercury
d) sediment
e) acid deposition
Station 6: Secondary Air Pollutants
Photochemical Smog
The burning of fossil fuels like gasoline can create another atmospheric pollution problem known as photochemical smog. Photochemical smog is a condition that develops when primary pollutants (oxides of nitrogen and volatile organic compounds created from fossil fuel combustion) interact under the influence of sunlight to produce a mixture of hundreds of different and hazardous chemicals known as secondary pollutants. The Table below describes the major toxic constituents of photochemical smog and their effects on the environment. Development of photochemical smog is typically associated with specific climatic conditions and centers of high population density. Cities like Los Angeles, New York, Sydney, and Vancouver frequently suffer episodes of photochemical smog.
Tropospheric Ozone
Ozone is found in two regions of the Earth's atmosphere – at ground level and in the upper regions of the atmosphere.Both types of ozone have the same chemical composition (O3).While upper atmospheric ozone protects the earth from the sun's harmful rays, ground level ozone is the main component of smog.
Ground level or "bad" ozone (tropospheric ozone) is not emitted directly into the air, but is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight. Emissions from industrial facilities and electric utilities, motor vehicle exhaust, gasoline vapors, and chemical solvents are some of the major sources of NOx and VOC. Ozone is likely to reach unhealthy levels on hot sunny days in urban environments. Ozone can also be transported long distances by wind. For this reason, even rural areas can experience high ozone levels.Voluntary and innovative programs encourage communities to adopt practices, such as carpooling, to reduce harmful emissions.
Practice Question:
What would be the best practice out of those listed below to reduce photochemical smog and tropospheric ozone levels?
a) reducing the amount of gasoline burned
b) reducing the amount of natural gas burned
c) reducing the amount of wood burned
d) reducing the amount of coal burned
Station 7: Different Air Pollutants
Outdoor:
1) Particulate Matter: Ex’s dust, asbestos, lead
Description: Reduces amount of sunlight that reaches surface of earth
From: burning fossil fuels, electrical insulation, roofing, paint, hair, skin, gas
2) Nitrogen Oxides (NOx)
Description: Inhibit plant growth, major cause of photochemical smog, reacts in the atmosphere to form acid rain
From: Combustion of fossil fuels from autos, fertilizer application, burning crop residues, creation of nitric acid
3) Sulfur Oxides (SOx)
Description: irritates the respiratory tract, degrades metal and stone, reacts in the atmosphere to form acid rain
From: Burning fuel containing sulfur, energy utilities, volcanoes
4) Carbon Oxides (COx)
Description: CO is poisonous, and reduces red blood cells ability to carry oxygen, CO2 causes global warming
From: Solid waste, burning fossil fuels, deforestation, automobile exhaust, wood burning.
5) Hydrocarbons (CHx); Volatile Organic Compounds
Description: Highly volatile compounds that cause cancer and global warming
From: Engine combustion, cow flatulence, wetland decomposition
6) Tropospheric Ground Level Ozone O3
Description: In troposphere, it is a secondary pollutant from when UV radiation catalyzes the reaction between NOx and CHx to form smog, causes cancer
From: See nitrogen and CHx statements
Indoor:
1) Radon
Description: A colorless, odorless gas that is created from the decay of uranium in the rocks. Can leak into a house traveling through the foundation and cause cancer.
From: Uranium decay of rocks
2) Biological Pollutants: Dust, Bacteria, Pollen
Description: Dust comes from dead hair and skin particles. Bacteria are found in your heating and cooling system house pets, bathrooms, and garage. Pollen is from plants. Causes allergies.
From: Hair, skin, pets, old food, plants
3) Mold
Description: A fungus that lives in and grows wells in moist, damp climates. Causes allergies, nausea, headaches, and fatigue.
From: Improperly created ventilation systems, heating and cooling systems, damp clothes, moisture in the ceilings and walls.
4) Chemicals: Formaldehyde
Description: Man made chemicals can decay over time, and be released as vaporous in the home. The most common is formaldehyde.
From: in particle board, fiber board, in plywood, furniture and paneling, carpeting, glues, upholstery and drapery fabrics.
5) Cigarette Smoke
Description: Created from the burning of cigarettes. When combined with all the chemicals in the environment, cigarette smoke can create more than 4600 different chemical compounds.
From: Cigarettes
7) Heavy Metals: Mercury and Lead
Description: Used to be used in paint (lead) and electrical switches (mercury). Causes cancer of the nervous system and nervous system damage
From: Paint, switches, thermometers
Station 8 : Water Treatment
Wastewater is not just sewage. All the water used in the home that goes down the drains or into the sewage collection system is wastewater. This includes water from baths, showers, sinks, dishwashers, washing machines, and toilets. Small businesses and industries often contribute large amounts of wastewater to sewage collection systems; others operate their own wastewater treatment systems. In combined municipal sewage systems, water from storm drains is also added to the municipal wastewater stream. The average American contributes 265-568 liters (66 to 192 gallons) of wastewater each day. Wastewater is about 99 percent water by weight and is generally referred to as influent as it enters the wastewater treatment facility. “Domestic wastewater” is wastewater that comes primarily from individuals, and does not generally include industrial or agricultural wastewater.
At wastewater treatment plants, this flow is treated before it is allowed to be returned to the environment, lakes, or streams. There are no holidays for wastewater treatment, and most plants operate 24 hours per day every day of the week. Wastewater treatment plants operate at a critical point of the water cycle, helping nature defend water from excessive pollution. Most treatment plants have primary treatment (physical removal of floatable and settle-able solids) and secondary treatment (the biological removal of dissolved solids).
Primary treatment involves:
1. screening- to remove large objects, such as stones or sticks, that could plug lines or block tank inlets.
2. grit chamber- slows down the flow to allow grit to fall out
3. sedimentation tank (settling tank or clarifier)- settle-able solids settle out and are pumped away, while oils float to the top and are skimmed off
Secondary treatment involves:
Using biological treatment processes, in which microorganisms convert non-settleable solids to settle-able solids. Sedimentation typically follows, allowing the settle-able solids to settle out. Three options include:
1. Activated Sludge- The most common option uses microorganisms in the treatment process to break down organic material with aeration and agitation, then allows solids to settle out. Bacteria-containing “activated sludge” is continually recirculated back to the aeration basin to increase the rate of organic decomposition.
2. Trickling Filters- These are beds of coarse media (often stones or plastic) 3-10 ft. deep. Wastewater is sprayed into the air (aeration), then allowed to trickle through the media. Microorganisms, attached to and growing on the media, break down organic material in the wastewater. Trickling filters drain at the bottom; the wastewater is collected and then undergoes sedimentation.
3. Lagoons- These are slow, cheap, and relatively inefficient, but can be used for various types of wastewater. They rely on the interaction of sunlight, algae, microorganisms, and oxygen (sometimes aerated).
After primary and secondary treatment, municipal wastewater is usually disinfected using chlorine (or other disinfecting compounds, or occasionally ozone or ultraviolet light). An increasing number of wastewater facilities also employ tertiary treatment, often using advanced treatment methods. Tertiary treatment may include processes to remove nutrients such as nitrogen and phosphorus, and carbon adsorption to remove chemicals. These processes can be physical, biological, or chemical.
Practice Question:
The goal of the second stage of a waste water treatment plant is to
a)Remove the large solid material
b)Aerate the water
c)Make muddy water clear
d)Remove chemicals such as DDT or PCBs
e)Lower the amount of organic material in the water
APES Review for Final: Stations
Directions:
- You have eight (8) minutes at each station before rotating.
- Read the paragraph of information at the station.
- Summarize the information on your own paper following the instructions below.
- Answer the practice question for that station.
- Rotate to the next station and perform steps “a-d” again.
For Each Station:
a)Write the station name down
b)Summarize the important points of the information provided. Use bullet points.
c)What is the answer to the multiple choice question?
d)What is the evidence that proves your answer is right? (It is okay to quote a sentence from the information)