APES unit 4: earth ecosystems/resources
resource: any substance, capability, or other asset that is available in a supply and can be accessed and drawn on, natural resources as an example
the five spheres of planet earth (more on these later):
solid earth (outer shell)
pedosphere (soil)
atmosphere (gasses)
hydrosphere (water)
biosphere (see page 157 for pic)
welcome to planet earth
table on pg 158
current epoch: holocene
most recent geologic periods: quaternary and tertiary
non-flying dinosaurs are from the: mezozoic era
most of the geologic time scale fell under the precambrian eons
next epoch: Anthropocene (recognizes human effect on nature)
the solid earth
three zones of rocks in the earth: (pg 159/160)
innermost is called the core
comprised of inner and outer core
next is the mantle
near the top of the mantle is slow moving rock called the asthenosphere
then the lithosphere
rigid rock
contains the crust (solid surface of the earth)
tectonic plates
Pangaea was supercontinent that broke apart and separated
tectonic plates are several large pieces of lithosphere that move slowly around the earth’s mantle
plate boundaries (places where plates meet):
convergent: two plates pushed together, one going under the other
often results in subduction
divergent: two plates moving away, new crust forming in the process
transform: plates sliding against each other in opp. directions
volcanoes and earthquakes
active volcanoes=erupted recently, dormant=have not, extinct=won’t erupt again
how volcanoes form:
subduction zones: subducting plate becomes new magma, which rises to form volcanoes
rift valleys: magma cooling at divergent boundaries
hot spots: found in the middle of tectonic plates where hot magma melts through the mantle and weakens the earth’s crust
four types of volcanoes: shield, composite, cinder, lava domes; just find picture online
earthquakes: result of vibrations (often from sudden plate movements) deep in the earth that release stored energy, often cause tsunamis
focus: location where an earthquake begins within the earth
epicenter: surface location of the earthquake
seismograph: measures size of earthquakes
Richter scale: measuring earthquakes on scale of 0 to 9.5
rock cycle (photo pg. 164)
rock cycle: rocks forming from other rocks. three types of rocks form:
igneous: rock that melts and cools, magma coming to the surface of the earth and cooling
sedimentary: sediment (eroded rocks, remains of plants and animals) is compressed together
metamorphic: pressure and heat create physical or chemical changes in existing rock
soil (pedosphere)
three classes: clay (small), silt (medium) and sand (biggest) (pg 165)
composition: mixture of these^ particles in a soil
porosity: number of holes it has
permeability: how things move through it
fertility: how things grow in it
loam: a soil is ideal for growth
water holding capacity: total amount of water a given soil can hold
soil pH: how acidic or basic soil is (affects what can grow in it)
acidic soil=damaging some plants and marine life
soil comes from weathering of organic material and rock (the process by which rock and other material decomposes, not to be confused with erosion)
physical weathering/mechanical weathering: rocks breaking down without chemically changing
chemical weathering: rock chemically reacting with water, air, etc.
biological weathering: weathering from physical organisms (like roots enlarging cracks in rock as they grow)
soil layers (pg 168)
horizons: soil comprises distinct layers called horizons
O horizon: organic matter
humus: residue left from decomposed dark
A horizon: top soil with the most minerals
for soils without an E horizon this also may be the zone of leaching
E horizon: light in color, course in texture, found in forests, eluviation zone
B: illuviation zone, accumulating products of the upper horizons
C: parent material, hard
R: consolidated (cemented) rock, surface rock
soil development
four processes of soil development
additions of material from off-site
losses of material through erosion, leaching, etc.
vertical translocations (movement from one soil horizon to the other)
transformations of materials by weathering or chemical act.
6 soil-forming factors (Cl O R P T H)
Climate
Organisms (biological activity)
Relief (topography) which affects where water is moving and its depth
Parent material
Time
Human influence (fertilizer, pollution, etc.)
atmosphere
atmosphere: layer of gases held close to the earth by gravity (pg 170)
troposphere: closest layer to us, all of the weather we experience
tropopause: layer that buffers for the next layer (stratosphere)
stratosphere: above tropopause, gases are not well mixed
temperature increases traveling up because of the ozone layer which traps the sun’s radiation
mesosphere: cold temps, where meteors burn up
thermosphere: northern lights
exosphere: furthest layer for satelites
ionosphere: layer dispered in mesophere, thermosphere, and exosphere where ions are
greenhouse effect: warming effect on our earth through greenhouse gases (pg 171 for pic)
weather: day to day patterns, climate: patterns over time
air circulation:
sun’s rays strike earth at equator, tilt of earth’s axis determines where light goes
coriolis effect (already learned this) creates resulting wind paterns called prevailing winds (pg 173)
convection currents: warmed gases expand, become less dense, and rise, while cooler air replaces their spots
creates horizontal airflow patterns, which form surface winds
when the air rises, it cools to the dew point, which is where it becomes liquid water. the liquid then falls which restarts the pattern (convection cell rotation) see pg 174
this phenomenon also creates hadley cells (pg 174)
seasons: see pg 175
albedo: percentage of insolation (incoming solar radiation) reflected by a surface, which determines climate
albedo of zero: absorbes all radiation, albedo of 1: reflects all radiation
wind types (pg 177)
wind: air that’s moving as a result of unequal heating of earth’s atmosphere
trade winds: strong winds
westerlies and polar easterlies: types of winds blowing due to coriolis effect
horse latitudes: areas bt 30-35 degrees north and south w weak winds
doldrums: area on either side of equator with weak winds
jet stream: high-speed wind occurring in the tropopause
weather formed by wind
monsoons (see pic pg 178)
lake effect: small scale monsoons
rain shadow effect: pg 179
hurricanes/typhoons/cyclones: high wind speeds that rotate and remove water vapor from earth’s surfaces, which then releases heat, which speeds up the winds even more
el nino: normal trade winds are weakened/reversed, called the Southern Oscilllation
pg 180 for pic
this stops the normal upwelling (cold water coming to the surface)
warmer winters in the US and Canda, less hurricanes
la nina:
contributed to by the coriolis effect
colder waters near equator
allowing upwelling
hydrosphere
freshwater: comes to earth through precipitation
watershed: land area that drains into a particular stream
deltas: areas where rivers meet the ocean and dump sediment off
ocean currents:
gulf stream: warm water through the u.s. to GB
ocean conveyor belt: pg 182