Unit 4- Earth Systems and Resources Flashcards
Mature soil
Soil that has at least 3 horizons and has taken 1000’s of years to develop.
Young soil
Poorly developed soil with only 1 or 2 horizons; less organic matter & fewer nutrients.
Immature soil
Bedrock and unbroken up rock and fragments, moss and lichen.
Bedrock
Rock that makes up Earth’s crust; also the solid rock layer beneath the soil. R horizon.
Soil horizon
The layer of soil that differs in color and texture from the layers above or below it.
Soil profile
A vertical section through a soil, from the surface down to the parent material, revealing the soil layers or horizons.
Sand
A naturally occurring grainy material made of finely divided rock and mineral particles; the most common ingredient is silica. Large particle size from 0.06 mm to 2.0 mm.
Silt
A grainy material with grain size between sand and clay. It is weathered from soil or rock. Has the consistency of flour.
Clay
A small soil particle. Only seen under an electron microscope. Important in determining soil characteristics- has the greatest surface area.
Soil fertility
Soil’s ability to hold nutrients and to supply nutrients to a plant.
Cation Exchange Capacity (CEC)
the capacity of a soil for ion exchange of cations between the soil and the soil solution. CEC is used as a measure of fertility, nutrient retention capacity, and the capacity to protect groundwater from cation contamination.
Chemical weathering
The process that breaks down rock and changes the chemical composition. (Hydrolysis, Oxidation, Carbonation, Acid Rain, Acidic Plants)
Physical weathering
The process that breaks down rock without a chemical change. (Climate changes, animals burrowing, pressures from pushing and shoving, freeze/thaw, expansion, condensing)
Erosion
Processes by which rock, sand, and soil are broken down and carried away (i.e. weathering, glaciation).
O horizon
The organic horizon at the surface of many soils, composed of organic detritus in various stages of decomposition. Able to retain water and nutrients. Has an organic composition from 20%-30%. Surface plant and animal litter forms humus.
Humus
Rich, dark organic material formed by decay of vegetable matter, essential to soil’s fertility.
A horizon
Top soil; composed of decomposed organic matter (humus) and some inorganic mineral particles. Help hold water and nutrients.
B horizon
Horizon of Accumulation. Subsoil, Reddish or yellowish in color. Composed of clays, aluminum, and iron deposited by illuviation, which is materials deposited from above.
Illuviation
Deposition of leached material in the lower layers of soil.
Leaching
Process in which various chemicals in upper layers of soil are dissolved and carried to lower layers and, in some cases, to groundwater.
Percolation
The downward movement of water through soil and rock due to gravity.
Leaf litter
Part of the O horizon that is dead and decaying plant and animal materials especially fallen leaves that cover the soil.
Mineral
Basic building blocks of rocks they are composed of elements bonded together. They are inorganic (metal to a non-metal).
Loam
Perfect agricultural soil with optimal portions of sand, silt, clay (40%, 40%, 20%).
Soil texture
Relative amounts of the different types and sizes of mineral particles in a sample of soil.
Top soil
Mixture of humus, clay, and other minerals that forms the crumbly, topmost layer of soil.
Soil porosity
Pores or spaces in the soil. The greater pores or spaces, the greater the water holding ability.
C horizon
Location of weathered bedrock or parent material; referred to as Regolith; Horizon not affected by biological activity and generally not affected by soil operations; absence of clays.
Compost
Decayed organic matter used for fertilizing and conditioning land.
Soil permeability
Rate at which water and air move from upper to lower soil layers.
Soil structure
The arrangement of soil particles that influence water and air movement through soil.
Soil erosion
Movement of soil components, especially topsoil, from one place to another, usually by wind, flowing water, or both. This natural process can be greatly accelerated by human activities that remove vegetation from soil.
Lithosphere
The solid, outer layer of the Earth that consists of the the crust and the rigid upper part of the mantle.
Asthenosphere
A plastic, or flowing, layer within Earth’s mantle situated below the lithosphere and which the lithosphere floats.
Plate Tectonic
Sections of the Earth’s crust that move due to convection currents.
Convection Cell
Unequal heating and cooling of the magma by the core of the Earth often makes a pattern of rising and sinking in a circular pattern.
Subduction Zone
A destructive plate margin where oceanic crust is being pushed down into the mantle beneath a second plate.
Geology
The scientific study of the origin, history, and structure of the earth as recorded in rocks
Convergent Plate Boundary
A region where plates are pushing together and where a mountain range, island arc, and/or trench will eventually form; often a site of much seismic and volcanic activity.
Divergent Plate Boundary
Boundary between tectonic plates in which the two plates move away from each other, and new crust is created between them.
Continental Crust
The portion of the earth’s crust that primarily contains granite, is less dense than oceanic crust, and is 20-50 km thick.
Oceanic Crust
the portion of Earth’s crust that is usually below the oceans and not associated with continental areas, thinner and higher in density that continental crust and basaltic rather than granitic in composition.
Seafloor Spreading
The process that creates new sea floor as plates move away from each other at the mid-ocean ridges.
Transform Plate boundary
Two plates sliding past each other
Troposphere
0-17 km above Earth’s surface, site of weather, organisms, contains most atmospheric water vapor. (temperature decreases with increasing altitude, pressure decreases). The air consists of 78% nitrogen, 21% oxygen, and then other gases.
Stratosphere
2nd layer of atmosphere; extends from 10 to 30 miles up; location of the beneficial ozone layer; contains 1000x the ozone as the troposphere; absorbs 95% of Ultraviolet radiation; temperature increases with altitude increase.
Mesosphere
50 to 80 km, most meteorites burn up here. Coldest layer of the atmosphere and temperature decreases with increasing altitude.
Thermosphere
Fourth layer of the atmosphere, as altitude goes up, temperatures go up and can reach 1,700 degrees C (hottest layer). Also called the ionosphere due to auroras occurring in this layer.
Exosphere
Layer of the atmosphere that enters into space. transition between atmosphere and space
Atmosphere
A mixture of gases that surrounds a planet, such as Earth, that is pulled in by gravity.
Tropopause
The boundary between the troposphere and the stratosphere.
Stratopause
Boundary between stratosphere and mesosphere.
Mesopause
The transition between the mesosphere and the thermosphere.
Convection Cell
Unequal heating and cooling of the air often makes a pattern of rising air, sinking air, and winds.
Hadley Cell
The atmospheric circulation cell nearest the equator in each hemisphere. Air in these cells rises near the equator because of strong solar heating there and falls because of cooling at about 30° latitude or the horse latitudes. This creates the trade winds. This cell causes the tropical climate at the equator and desert conditions at the horse latitudes.
Polar Cell
Weak circulation cell that occurs between 60 and 90 degrees latitude. Air in these cells rise at 60 degrees and causes rain in this area and falls because of cooling at 90 degrees. This creates the Easterlies.
Ferrel Cell
The middle atmospheric circulation cell that is caused by the flow of air from the Hadley and Polar cells. Air rises at 60 degrees and sinks at 30 degrees. This creates the Westerlies.
Rain Shadow Effect
Precipitation falls on the windward side of a mountain range, resulting in lush vegetation & a warm, moist climate on one side, but a desert area on the leeward side.
ENSO
El Nino Southern Oscillation, trade winds weaken & warm surface water moves toward South America. Diminished fisheries off South America because of decreased upwellings, drought in western Pacific because of warmer temperatures, increased precipitation in southwestern North America because of warmer temperatures, and fewer Atlantic hurricanes. Occurs every 3 - 7 years.
La Nina
Colder than a “Normal” year, easterly trade winds and ocean currents are stronger than normal and pool warm water in the western Pacific, allowing upwelling of nutrient rich water off the West coast of South America. Occurs every 7 - 12 years.
Upwelling
Movement of nutrient-rich bottom water to the ocean’s surface. This can occur far from shore but usually occurs along certain steep coastal areas where the surface layer of ocean water is pushed away from shore and replaced by cold, nutrient-rich bottom water.
Thermocline
In water, a distinctive temperature transition zone that separates an upper layer that is mixed by wind (the epilimnion) and a colder, deep layer that is not mixed (the hypolimnion).
Thermohaline Circulation
Movement of ocean water caused by density difference brought about by variations in temperature and salinity. As ocean water freezes at the poles it concentrates salt, and the colder, denser water sink