Unit 4: Earth Systems and Resources

core

made of iron and nickel (metals), hot

mantle

thickest layer of Earth’s interior

Magma

moletn rock circulates

Asthenosphere

semi-molten, flexible outer layer of mantle

Lithosphere

thin, brittle layer of rock floating on top of mantle (broken into tectonic plates)

Crust

very outer layer of the lithosphere, Earth’s surface

Earth’s layers

core, mantle, asthenosphere, lithosphere, crust

divergent

plates move away from each other

causes of divergences

rising magma plumes from mantle force plates apart

forms mid-ocean ridges, volcanoes, seafloor spreading

convergent

plates move towards each other

subduction

one plate being forced beneath another

buckling

plates popping up

convergence causes

forms mountains, islands, arcs, volcanoes

transform

plates slide past each other

transformation causes

earthquakes, faults

ring of fire

pattern of volcanoes and earthquakes zone all around Pacific plates

hotspots

areas of especially hot magma rising up to lithosphere

ex. Hawaii

divergent plate boundary example

atlantic ocean

convergent plate boundary example

India -china border

transform plate boundary example

west coast of california

soil

mix of geologic (rock) and organic (living) components

Humus

main organic part of soil (broken down biomass like leaves, dead animals etc.)

soil components

sand silt clay, nutrients, water and air, living organisms

Plants role in the ecosystem

anchors roots, provides water, shelter, and nutrients

Waters role in the ecosystem

filters rainwater and runoff by trapping pollutants in pore spaces and plant roots, clean water enters groundwater and aquifers

Nutrient recycling role in the ecosystem

home to decomposers that break down dead organic matter and return nutrients to the soil

Habitat role in the ecosystem

for earthworms, fungi, bacteria, moles, slugs

Weathering

break down of rocks

Erosion

movement/transportation of rocks

Soil formation from below

weathering of parent material produces smaller fragments that make up geological/inorganic part of soil

Soil formation from above

breakdown of organic matter adds humus to the soil, erosion deposits soil particles from other areas, adding to soil

Soil horizons top to bottom

O Horizon, A Horizon, B Horizon, C Horizon

O Horizon

organic matter (plant roots, dead leaves) on top of soil, prevents evaporation

A Horizon

Topsoil - layer of humus and minerals from parent material

biological activity breaking down organic matter to release nutrients

B Horizon

subsoil - lighter layer below topsoil, mostly minerals with little to no organic matter

C Horizon

weathered rock (bedrock) - least weathered soil that’s closest to the parent material

soil degradation

loss of the ability of soil to support plant growth

compaction

squishing down soil

reduces ability to hold moistureloss of topsoil effects

loss of topsoil effects

easily eroded, dries out soil, removes recycling nutrients

nutrient depletion effects

repeatedly growing crops on same soil removes key nutrients

soil texture

percent of sand, silt, and clay in a soil

adds up to 100%

porosity

how much water that a soil sample can hold

soil pores

empty space between particles

permeability

how easily water drains through soil

H20 holding capacity

how well water is held by soil

too sandy soil

too permeable so roots dry out

too much clay soil

not enough drainage, waterlogged

soil fertility

ability of soil to support plant growth

factors that increase soil nutrients

humus, organic matter, decomposers, clay

factors that decrease soil nutrients

acids, excessive irrigation/farming, topsoil erosion

factors that increase water holding capacity

aerated soil, organic matter, clay, root structure

factors that decrease water holding capacity

compacted soil topsoil erosion, sand, root loss

percent of gases of Earth’s atmosphere

nitrogen: 78%

oxygen: 21%

argon: 0.93%

Water vapor: 0.4%

Carbon dioxide: 0.04%

exosphere

outermost layer where atmosphere merges with space

thermosphere

absorbs harmful x-rays and uv radiation

hottest temperature

mesosphere

middle

lower temperatures bc lower density

stratosphere

thickest 03 layer, absorbs carcinogenic uv rays

higher temperatures bc warmed by uv ryas

troposphere

most of atmosphere’s gas molecules and water vapor found here

90% of all gases in atmosphere

lower temperatures bc air is further from warmth of Earth’s surface

as altitude increases

air density decreases

layers of Earth’s atmosphere bottom to top

troposphere, peak ozone layer, stratosphere, mesosphere, thermosphere, exosphere

air properties

warm air rises: holds more moisture, less pressure so volume increases as it rises, expansion causes it to cool (adiabatic cooling)

cool air can’t hold as much H20 vapor (condenses and rains)

sinking air experiences more pressure so volume decreases, contraction causes it to warm (adiabatic warming)

coriolis effect

deflection of objects traveling through atmosphere due to spin of Earth

wind between 0-30 degrees moves

east to west bc earth moves west to east

wind between 30-60 degrees moves

west to east bc earth spins faster at 30 degrees than 60 degrees

watershed

all of the land that drains into a specific body of water (river, lake, etc.)

insolation (incoming solar radiation)

amount of solar radiation reaching an area

watts/m²

June and December solstices

N or S hemisphere is maximally tilted toward sun (summer/winter)

march and September equinox

N and S hemispheres equally facing the sun

albedo

reflectivity of a surface

increased albedo

reflect more light, absorb less heat

ex. ice, snow

decreased albedo

reflect less light, absorb more heat

ex. water, pavement, vegetation

windward side

green and rainy, side where wind is coming from (oceans)

warm moist air rises on mountains, air cools and condenses into clouds and rain

leeward side

dry deserts, side opposite of oceans/winds directions

air already “dropped off” water and is now dry, as it sinks down mountain, it warms