Clearcutting
a timber harvesting technique that involves removing all or almost all the trees within an area
Crown fire
Extremely hot and destructive forest fire that burns ground vegetation and treetops.
Deforestation
The removal of trees without replacing them.
depletion time
The time it takes to use up a certain proportion (usually 80%) of the reserves of a mineral at a given rate of use
Ecological Footprint
A measure of how much an individual consumes, expressed in area of land or number of earths.
gangue
the commercially valueless material in which ore is found.
geology
the study of the origin, history, and structure of Earth
high-grade ore
Ore that contains a fairly large amount of the desired mineral.
Impervious Surface
Any surface through which water can NOT seep down into the ground
Infiltration
Downward movement of water through soil.
low-grade ore
Ore containing a small amount of a desired mineral.
mineral
a naturally occurring, inorganic solid that has a crystal structure and a definite chemical composition
mountaintop removal
Type of surface mining that uses explosives, massive shovels, and even larger machinery called draglines to remove the top of a mountain to expose seams of coal underneath a mountain.
Old Growth
Forests that have not been cut - or not in a very long time. They generally include more large trees, canopy layers, standing snags, native species, and dead organic matter.
open-pit mining
A mining technique that uses a large hole in the ground, visible from the surface of Earth.
ore
Rock that contains a metal or economically useful mineral
overburden
Layer of soil and rock overlying a mineral deposit.
Prescribed burn
A fire deliberately set under controlled conditions in order to reduce the accumulation of dead biomass on a forest floor
reserves
minerals that have not been accessed yet.
second growth
Forests that have been cut.
Selective Cutting
The method of harvesting trees that involves the removal of single trees or a relatively small number of trees from among many in a forest.
smelting
The process by which ore is melted to separate the useful metal from other elements.
Slag
waste residue from smelting metal.
spoil
a pile of overburden that has been moved
strip mining
involves the removal of the Earth's surface all the way down to the level of the mineral seam.
subsurface mining
Extraction of a metal ore or fuel resource such as coal from a deep underground deposit.
Surface fire
Forest fire that burns only undergrowth and leaf litter on the forest floor.
surface mining
The extraction of mineral and energy resources near Earth's surface by first removing the soil, subsoil, and overlying rock strata.
Sustainable Yield
Highest rate at which a potentially renewable resource can be used indefinitely without reducing its available supply.
Tailings
Piles of rock and other waste materials removed as impurities when waste mineral material is separated from the metal in an ore.
Tragedy of the Commons
the tendency of a shared, limited resource to become depleted because people act from self-interest for short-term gain
Tree plantation
planted stands of a particular tree species
Urban Sprawl
The process of urban areas expanding outwards, usually in the form of suburbs, and developing over fertile agricultural land.
coal ash
waste from coal mining that contains mercury, arsenic and lead
Urbanization
Movement of people from rural areas to cities
Pine beetle
Warmer, milder summers cause this insect to feed on the bark of conifers, killing the trees (climate change alters forests!)
dutch Elm disease
One of several fungi destroying large numbers of deciduous trees