Alley Cropping
The planting of rows of trees and/or shrubs to create alleys within which agricultural or horticultural crops are produced
Contour Planting
The practice of tillage, planting, and other farming operations performed on or near the contour of the field slope.
Erosion
The geological process in which earthen materials are worn away and transported by natural forces such as wind or water.
Anemia
Low levels of hemoglobin due to iron deficiency or lack of red blood cells; Lack of red blood cells = not enough oxygen for body's tissues
Divergent Plate Boundary
Occurs when two tectonic plates move away from each other; Earthquakes are common and magma rises from the mantle to the surface, creating new oceanic crust
Transform Plate Boundary
Occurs when tectonic plates slide past each other along large cracks or fractures in the Earth's crust; Found in the ocean basin and connect offsets in the mid-ocean ridges.
Dependent Variable
The factor that is predicted to change as a result of variation in the independent variable.
Independent Variable
The variable that is manipulated through the course of an experiment
Reserves
Resources that have been identified and from which a usable mineral can be extracted profitably at present prices with current mining technology.
Rare Earth Materials
A group of 15 chemical elements in the periodic table (lanthanides) categorized into light and heavy elements; Scandium, lanthanum, yttrium, etc
Isotopes
Two atoms that have the same atomic number, or belong to the same element, but have a different mass number/number of neutrons
Conservation Tillage
An agricultural management approach that aims to minimize the frequency or intensity of tillage operations in an effort to promote certain economic and environmental benefits.
Acid Mine Drainage
Occurs when rainwater seeps through a mine or mine wastes and carries sulfuric acid to nearby streams and groundwater, contaminating water supply and destroying some forms of aquatic life.
Overburden
The rock and soil removed over ore
Ore
Part of a metal-yielding material that can be economically and legally extracted at a given time; Contains a large enough concentration of a particular mineral to profitably mined and extracted.
Oceanic Trench
A long, narrow, steep-sided depression in the ocean floor in which maximum oceanic depths occur; forms in locations where one tectonic plate subducts under another.
Subduction
When an oceanic plate collides with a continental plate and rides up over the denser plate, pushing it down to the mantle
Convection Currents
Global patterns of air movement that are initiated by the unequal heating of Earth
Positive Feedback Loop
Occurs when increased output in a system leads to increased input, which further simulates output
Ex. Melting of glaciers and sea ice in the arctic
Negative Feedback Loop
A feedback loop that causes a system to change in the opposite direction from which it is moving
Ex. Reproduction --> overgrazing --> less reproduction
Malnutrition
A condition that results from eating a diet in which nutrients are either not enough or are too much such that the diet causes health problems.
Undernutrition
Occurs when not enough calories are being consumed.
Depletion Time
The time it takes to use up a certain proportion (usually up to 80%) of the reserves of a mineral at a given rate
Intensive Agriculture
Producing enough food for a large farm family's survival and a planned surplus that is sold for profit; High output per unit area.
Monoculture
The agricultural practice of producing or growing a single crop, plant, or livestock species, variety, or breed in a field or farming system at a time.
Polyculture
Where more than one crop is grown in the same space at the same time.
Tipping Point
Delicate thresholds where a relatively slight rise, typically in an environmental problem, can cause a more dramatic change.
Synergistic Interaction
Occurs when 2 or more processes interact so that the combined effect is greater than the sum of their separate effects.