2J04 Mid-Term Review STAR Questions L1

2J04 Mid-Term Review
STAR Questions
L1
L2
What is the most influential abiotic factor? Sunlight
What is ecotone? The transitional region b/w different ecosystems. Share
many of the species and characteristics of both ecosystems.
Major Trophic Categories of Organisms: 1) Producers 2) Consumers 3)
Detritus feeders 4) decomposers
L3
How is the role of autotrophs and heterotrophs different or the same?
What are limiting factors in ecosystems?
Know the nutrients cycles (carbon, phosphorus, nitrogen).
What are the violations of 1st and 2nd principles of ecosystems
sustainability?
Learn 3 ecosystems services and functions
L4-5
What is climax ecosystem? Is the equilibrium b/w species and physical
environment, and the balance b/w the two.
L6
Learn the soil profile.
Learn soil classes.
What is productive soil?
What is the cause of soil degradation in NA? SA? Europe? Etc.
L7-8
Learn the top five elements.
Rank the atom bonds from strongest to weakest.
L9-10 Engineering applications.
Rock cycle.
L11
Rock cycle.
What is lithification? Refers to the processes (compaction and
cementation) by which unconsolidated sediments are transformed into
solid sedimentary rocks.
Learn engineering applications
L12
Engineering App.
L13-14 What are body (S & P) waves?
What is the difference b/w magnitude and intensity?
What are the structural design factors?
L15
L16
L17
Identify the merits and limits of each method (arithmetic, thiessen,
isohyetal).
Time of concentration? – What are the factors that can affect Tc (from up
stream to down)? (obsicales like rock and roots).
What is DRH?
L18
Estimate snowmelt: M?
L1: Ecosystems
 Ecosystem – grouping of species (plants, animals…) in a given area and
interacting with each other and their environment.
 Ecology – the study of ecosystems and interactions among organisms and
their environment.
 Biotic – (Living) community in a specific environment.
 Abiotic – (non living) include water, air, soil, temperature, wind, sunlight…
 Decline of Ecosystems/ Human impact – oceans overfished, forest cut faster
than it can grow (deforestation), pollution, change in climate, agricultural soil
degradation, depletion of supplies (groundwater).
 Importance of Ecosystems – support human life, economy, agriculture, etc.
Also sustain biodiversity.
 Global Environmental Picture – rapid human population growth and
increasing consumption per person, decline of vital life-support ecosystems,
global atmospheric changes, loss of biodiversity.
 Three unifying themes – Sustainability, Stewardship, and Sound Science.
o Sustainability –
o Stewardship – (we don’t own environment but take care of it), desire
to pass something on to future generations
o Sound Science – (can reproduce) causes and effects are explainable,
experiments and observations.
L2: Ecosystem Structure
 Ecosystem – grouping of species (plants, animals…) in a given area and
interacting with each other and their environment (ex: oceans, forests).
 How ecosystems are formed: abiotics (moisture and temperature) create
plants (moisture = forest; temperature = forest type), which creates animals.
 Ecotone – transitional region between different ecosystems. They share
many of the species and characteristics of both ecosystems.
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Inorganic
Organic
 oxygen
 all living things
 carbon dioxide
 products of living things
 nitrogen
 water
 pH
 What is trophic?
 Major Trophic Categories of Organisms:
1) Producers (green plants, photosynthesis) autotrophs (“self-feeding”)
chlorophyll
2) Consumers (bacteria, insects, reptiles, mammals, etc.) heterotrophs
(feeded by/with other organisms)
o Primary consumers (herbivores; eat plant material)
o Secondary consumers (carnivores; eat herbivores and other animals)
o Higher level consumers (parasites; eat plants or animals)
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3) Detritus feeders (worms, termites, ants, etc.; eat plants or animals)
4) Decomposers (fungi, bacteria; eat plants or animals)
Limiting abiotic factors: nitrate, temperature, and altitude.
L3: Ecosystems – How they work?
 Transfer of Energy and Nutrients: capture of sun energy and transfer through
different trophic levels.
 Atmospheric gases: nitrogen 78%, oxygen 21%, carbon dioxide <0.04%
 Elements of Life:
o Organic = carbon based molecules (molecules that make up tissue of
living things are constructed mainly from natural organic molecules.
o Inorganic = molecules without carbon-carbon nor carbon-hydrogen
bonds
 Law of Thermodynamics (energy)
o Frist law: energy is neither created nor destroyed; only converted.
o Second law: in any energy conversion you will end up with less usage
energy than you started with.
 Principles of Ecosystem Sustainability:
1) Ecosystems use sunlight as their source of energy (photosynthesis).
2) Ecosystems dispose of their wastes and replenish nutrients by recycling
elements.
3) Ecosystems show flexibility when subject to disturbance.
4) Ecosystems depend on biodiversity.
 Major/largest source of Carbon: Air (CO2) – 0.04%
 Carbon Cycle:
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Phosphorus Cycle:
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Phosphorus is a limiting factor in ecosystems
Human impact: fertilizer, sewage sludge.
Nitrogen Cycle:
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Main/largest reservoir (Air 78%)
Limiting factor in ecosystems
Human Cycle
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Violations of the First Principle of Ecosystem Sustainability:
o Excessive use of fossil fuels.
o Feeding largely on third trophic level.
o Use of coal and nuclear power.
o Use of agricultural land to produce meats.
Violations of the Second Principle of Ecosystem Sustainability:
o Lack of recycling.
o Excessive use of fertilizers.
o Destruction of tropical rain forests.
Ecosystem Services and Functions:
o Water supply
o Waste treatment
o Gas, climate, water
o Food production
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regulation
o Soil formation
o Erosion control
o Raw materials
L4-5: Ecosystem Balance, Change and Adaptation
 Population Equilibrium: the balance b/w birth and death rates
 Biotic potential: ability of populations to increase (reproductive rate,
migration, defenses)
 Environmental Resistance: combination of biotic and abiotic factors that may
limit population increase (predators, competitors, diseases, unfavorable
weather, limited food/nutrients).
o Density-independent factors: effects do not vary with population
density. (Ex: unfavorable weather)
o Density-dependent factors: effect varies with population density (Ex:
infectious disease (with high population, disease spread easily))
 Climax Ecosystem: is the equilibrium and balance b/w all species and
physical environment
 Fire Climax Ecosystems: dependent upon fire for maintenance of existing
balance (nutrient release to soil, regrowth of roots and seeds).
L6: Soil and Soil Ecosystem
 Soil Profile:
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90% of the world’s food comes from land-based agriculture.
Soil Classes:
o Mollisols: fertile soils with deep A horizon (best agriculture soil)
o Oxisols: iron and aluminum oxides in B horizon (poor agriculture soil)
o Alfisols: well-developed O, A, E and B horizon (suitable for agriculture
if supplemented with organic matter)
o Aridisols: little vertical structure; thin and unstable for sustainable
agriculture
Productive Soil – good supply of nutrients and nutrient-holding capacity;
good water infiltration and water-holding capacity; resists evaporative water
loss; porous structure for aeration; near-neutral pH; low salt content.
Soil Degradation – poor farming practices = loss of soils and farmland due to
erosion and salinization.
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Salinization – a process of distilling out dissolved salts in irrigated water and
leaving it on the land. A form of desertification, since land is rendered
useless.
Irrigation – flood irrigation; supply water to land/crops to help grow.
L7-8: Minerals (CCW pg45)
 Geology – the study of the physical nature of the earth and its history.
 Mineral – is a natural inorganic solid with a definite chemical structure.
o The building blocks of minerals are atomic elements.
o The basic building blocks of rocks and soils are minerals.
 These minerals make up approx. 90% of the earth crust.
o O, Si, Al, Fe, Ca (largest to lowest)
 Atom Bonds (ranked from strongest bonding to weakest):
o Covalent Bond – sharing electrons (Ex: SiO44-)
o Ionic Bond – transfer of electron (Ex: NaCl)
o Metallic bonding – “electrical glue” b/w metals (Ex: Al and Ag)
 Physical Properties of Minerals:
1) Colour and Streak
2) Hardness – resistance to abrasion and scratching
3) Mohs Scale – of mineral hardness
4) Cleavage – tendency to break along preferred planes
5) Fracture – O, Si rich mineral
6) Crystal Form
7) Luster – appearance of mineral reflected in light (O, Si rich mineral)
 Rock-Forming Minerals:
1) Silicates – makes up the largest and most important class of rock-forming
minerals. Which all contain silicon and oxygen(SiO44- ion silicate)
o Common Silicate Minerals:
Family
Group
Ferromagnesian
Olivine
(dark silicate)
Pyroxenes
Amphiboles
Micas
Non-ferromagnesian
Feldspars
(light silicate)
Quartz (silica)
Resistant to weathering
o Fledspars: most common mineral in igneous rocks; usually light in
colour; pronounced planes of cleavage.
 Asbestos: Group of silicate minerals made of very thin and strong fibers.
2) Non-Silicate Minerals
a. Carbonates – soluble in water
b. Sulfates
c. Metallic Ore Minerals
 Minerals Diagram:
L9-10: Igneous Rocks
 Rock – is a compact, semi-hard to hard mass of natural material composed of
one or more minerals
 Igneous rock – formed from crystallization/solidifies of molten (rock)
magma (from the earth’s centre).
 Magma – consists mainly of silicate materials gases and water
 Lava – similar to magma, but poor in gas
 Texture – arrangement and size of grains
o Factors affecting igneous rock texture: time magma cools, amount of
silicate present, amount of dissolved gases in the magma.
 Structure: features of rocks, depends on
o Crystallization (ordered pattern of ions) – rate of cooling , slow
cooling = large crystal; fast cooling = fine crystals.
o Amorphous (unordered pattern of cooling) – occurs when instant
cooling.
 Engineering Applications
Igneous Rock
Use/App
Gabbro, Dolerite, Bassalt
Construction stone, roadstone and aggregate
Dolerite
Good binding properties with bitumen
Granite
Important structural stone
L11: Sedimentary Rocks
 Formation Processes:
o Weathering (physical & chemical)
o Compaction and/or Cementation (lithification) – of sediment into
solid rock.
 Lithification – refers to the processes (compaction and cementation) by
which unconsolidated sediments are transformed into solid sedimentary
rocks,
 Classification:
Group/Origin
Texture
Composition
Rock
Detrital
Clastic
Sand, salt, clay
Sandstone
fragments
Siltstone
Chemical
Clastic or NonCalcite, plant
Limestone
clastic
remains
Salt
Coal
 Engineering Appication:
Rocks
Application/Use
Limestone
Excellent aggregate; mixes well
Salt rocks
Landfill; reduces smell; slow
decompose of material
Sandstone
Good filling material
L12: Metamorphic Rocks
 Formation Process (metamorphism) is the transformation of one rock into
another b/c of change in temperature and/or pressure.
 How metamorphism Transform Rocks?
o Texture change: parallel realignment of minerals (foliation) due to
shear stresses; growth of new minerals (schistosity); separation of
minerals (gneiss).
o Mineralogical change: recrystallization to form new minerals.
 Classification (textural)
Texture
Parent Rock
Metamorphic
Application/Use
Rock
Foliated
Shale
Slate
Roofing
Granite, gabbro
Schist
Filling material
Granitic & volcanic
Gneiss
Aggregate
rocks
Non-foliated Limestone, Dolostone Marble
Flooring
Sandstone
Quartzite
Construction
L13: Earthquakes & Seismology
 Earthquakes – are caused by vibrations that occur when tectonic plates move
against one another. They usually appear along large fractures called faults,
associated with boundary plates.
 Epicenter – is the surface location that is directly above the focus/center of
the earthquake.
 Seismology – the study of earthquake waves.
 Two main types of seismic waves:
o Surface waves: travel along the outer layer of the earth. Slowest
waves. The most important are Love (L) waves, which can produce
large displacements of the ground surface and are the most
destructive.
o Body waves: which travel through earth’s interior are divided into to
waves:
 Primary (P) waves – produce pressure by alternately pushing
(compress) and pulling (dilate) rocks.
 Sceondary (S) waves – cause shaking of rocks due to
perpendicular oscillations.
o S-waves are 1.7times slower than P-waves.
 Triangulation Method (need 3 locations)
 Ritcher Scale: total amount of energy released; The magnitude is determined
by measuring the amplitude of the largest seismic wave recorded.
o An increase of 1.0 magnitude = a tenfold increase in wave amplitude.
 Modified Mercalli (MM) Intensity Scale: expresses intensity of a quake’s
effects in a specific area.
 Difference b/w Magnitude and Intensity:
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o Magnitude measures the strength of the quake (based on wave
amplitude.
o Intensity expresses the destructiveness of the quake (based on
magnitude (Ms), distance from epicenter, duration of vibrations,
building design, nature of rock or mineral, and population density.
Frequency Analysis:
o Exceedance probability (Ex: What is the probability of having a quake
greater than 4.5 in Toronto?)
 Pr(q>X) = r/(n+1)
 R = rank
 N = number of quakes
o Non-exceedance probability 1-Pr(q>X)
o Return period (T)
 T = 1/[Pr(q>X)] = (n+1)/r
o The probability R (called the Risk) that an exceedance occurs at least
once in k successive years.
 R = 1-[1-(1/T)]K
L15: Soil Classification
 Soil particles (largest to smallest) sand (2 – 0.02mm) – silt (0.02 – 0.002mm)
– clay (<0.002mm)
 Stokes’ Law – gives the velocity (v) of falling spheres in fluid (w). That
depends on particle size (D), its specific gravity (Gs), and the specific gravity
of fluid (Gw) and its viscosity (μ).
o v = D2(Gs-Gw)/18μ
 Plasticity of soil – ability to undergo deformation without volume change or
rupture.
o Plasticity Index: PI = LL – PL
 Liquid limit (LL or WL) is the water content at which it would require 25
blows to close the groove over 12 mm length
o Blows = cup impacts on standard base
L16: Surface Water: Hydrology Water Use and Management
 Base flow – lowest volume of water necessary to maintain the river flow and
its biotic organisms.
 Water cycle processes:
o Evaporation: water molecules move from liquid to gaseous state.
o Condensation: water molecules move from gaseous to liquid or frozen
state.
o Precipitation: occurs when relative humidity (r.h.) reaches 100% and
cooling continues.
L 17: Principles of Hydrology
 Identify the merits and limits of each method
Method
Merits/advantages
Arithmetic Mean
Easy & fast
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Thiessen Polygon
Suitable for flat areas
Isohyetal Method
Most accurate approach
Limits
Assume uniformity and
flat topography
Unsuitable for
mountainous areas
Requires good
topographic data
Arithmetic mean method:
n
o PAri = 1/n Σ Pi
i=1
Thiessen polygon method:
n
o PAri = 1/n Σ Pi Ai
i=1
1) Connect rain gauge locations
2) Draw perpendicular bisectors
3) Compute areas covered by each gauge
Isohyets method:
o Lines of equal rainfall depth (like contour lines)
Discharge – volume of water that passes a specific in a unit of time.
Time concentration (Tc)
o Time requied for 100% of watershed to contribute to direct runoff.
o Tc = tqe – tie
o Tqe – end of direct runoff
o Tie – end of effective rain
L18: Hydrology – Snow and Snowmelt Processes
 Cold Content – the amount of energy required to increase the snow
temperature to 0°C.
 How to calculate snowmelt?
o Snowmelt (M) – units m/s
 M = Qm/λρ
 Qm – energy available for melting (W/m2)
 λ – latent heat of fusion (333kJ/kg)
 ρ – density of water (1000 kg/m3)
o How to find Energy of Snowmelt?
 Qm = Q* + QH + QE + QG + QR
 Qm = Q* + QH (the other Qs can be negligible)
 Qm : energy available for melting
 Q* : net radiation
 QH : sensible heat flux (convective transfer)
QE : latent heat flux (condensation transfer) – used in
mountainous areas.
 QG : ground heat flux (negligible if too cold)
 QR : energy flux from rainfall (negligible)
o Radiation Melt Energy (Q*)
 Q* = (1-α)K + (L – L)
Degree-Day Method: temperature index method (non-rainy days)
o M = a + b(Ta – To) = mm/day
o Ta : air temperature
o To : reference temperature (32°F)
o a : constant (often set to zero)
o b : melt per degree-day (degree-day = deviation of 1° from given date
temperature over a 24-hr period.
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