An Outline of American Geography |
GLOSSARY
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A B C D E F G H I J K L M N O P Q R S T U W Z
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Absolute Humidity:
The mass of water
vapor in
the atmosphere per
unit of volume of space.
Accessibility:
A locational
characteristic
that permits a place
to be reached by the efforts of those at other places.
Accessibility Resource:
A naturally
occurring
landscape feature
that facilitates interaction between places.
Acid Rain:
Rain that has
become more acidic
than normal (a pH
below 5.0) as certain oxides present as airborne pollutants are
absorbed by the water droplets. The term is often applied
generically to all acidic precipitation.
Air Mass:
A very large body
of atmosphere
defined by essentially
similar horizontal air temperatures. Moisture conditions are
also usually similar throughout the mass.
Alluvia:
Clay, silt,
gravel, or similar
detrital material
deposited by running water.
Alluvial Soils:
Soils deposited
through the
action of moving
water. These soils lack horizons and are usually highly fertile.
Antebellum:
Before the war;
in
the United
States, belonging to
the period immediately prior to the Civil War (1861-1865).
Anthracite:
A hard coal
containing little
volatile matter.
Arete:
A sharp, narrow
mountain ridge. It
often results from the
erosive activity of alpine glaciers flowing in adjacent valleys.
Arroy:
A deep gully cut
by a stream that
flows only part of the
year; a dry gulch. A term normally used only in desert areas.
Badlands:
Very irregular
topography resulting
from wind and water
erosion of sedimentary rock.
Base Level:
The lowest level
to which a
stream can erode its bed.
The ultimate base level of all streams is, of course, the sea.
Batholith:
A very large body
of igneous rock,
usually granite,
that has been exposed by erosion of the overlying rock.
Bedrock:
The solid rock
that underlies all
soil or other loose
material; the rock material that breaks down to eventually form
soil.
Bilingual:
The ability to
use
either one of
two languages,
especially when speaking.
Biological Diversity:
A concept
recognizing
the variety of life
forms in an area of the Earth and the ecological interdependence
of these life forms.
Biota:
The animal and
plant life of a region
considered as a
total ecological entity.
Bituminous:
A soft coal that,
when heated,
yields considerable
volatile matter.
Boll Weevil:
A small, greyish
beetle of the
southeastern United
States with destructive larvae that hatch in and damage cotton
bolls.
Break-in-Bulk Point:
Commonly, a
transfer
point on a transport
route where the mode of transport (or type of carrier) changes
and where large-volume shipments are reduced in size. For
example, goods may be unloaded from a ship and transferred to
trucks at an ocean port.
Butte:
An isolated hill
or mountain with
steep or precipitous
sides, usually having a smaller summit area than a
mesa.
Caprock:
A strata of
erosion-resistant
sedimentary rock (usually
limestone) found in arid areas. Caprock forms the top layer of
most mesas and buttes.
Carrying Capacity:
The number of
people that
an area can support
given the quality of the natural environment and the level of
technology of the population.
CBD:
The central
business district of an
urban area, typically
containing an intense concentration of office and retail
activities.
Chaparral:
A dense,
impenetrable thicket
of
shrubs or dwarf
trees.
Chinook:
A warm, dry wind
experienced along
the eastern side of
the Rocky Mountains in the United States and Canada. Most common
in winter and spring, it can result in a rise in temperature of
20C (35 to 40F) in a quarter of an hour.
Climax Vegetation:
The vegetation
that would
exist in an area if
growth had proceeded undisturbed for an extended period. This
would be the "final" collection of plant types that presumably
would remain forever, or until the stable conditions were somehow
disturbed.
Confluence:
The place at
which
two streams
flow together to form
one larger stream.
Coniferous:
Bearing cones;
from the conifer
family.
Continental Climate:
The type of
climate
found in the interior of
the major continents in the middle, or temperate, latitudes. The
climate is characterized by a great seasonal variation in
temperatures, four distinct seasons, and a relatively small
annual precipitation.
Continental Divide:
The line of high
ground
that separates the
oceanic drainage basins of a continent; the river systems of a
continent on opposite sides of a continental divide flow toward
different oceans.
Continentality::
The quality or
state of
being a continent.
Coulee:
A dry canyon
eroded by Pleistocene
floods that cut into
the lava beds of the Columbia Plateau in the western United
States.
Conurbation:
An extensive
urban
area formed
when two or more
cities, originally separate, coalesce to form a continuous
metropolitan region.
Core Area:
The portion of a
country that
contains its economic,
political, intellectual, and cultural focus. It is often the
center of creativity and change (see Hearth).
Crop-lien System:
A farm financing
scheme
whereby money is loaned
at the beginning of a growing season to pay for farming
operations, with the subsequent harvest used as collateral for
the loan.
Culture:
The accumulated
habits, attitudes,
and beliefs of a
group of people that define for them their general behavior and
way of life; the total set of learned activities of a people.
Culture Hearth:
The area from
which the
culture of a group
diffused (see Hearth).
Cut-and-Sew Industry:
The manufacture
of
basic ready-to-wear
clothing. Such facilities usually have a small fixed investment
in the manufacturing facility.
Deciduous Forest:
Forests in which
the trees
lose their leaves
each year.
De Facto Segregation:
The spatial and
social
separation of
populations that occurs without legal sanction.
Degree Day:
Deviation of one
degree
temperature for one day from
an arbitrary standard, usually the long-term average temperature
for a place.
De Jure Segregation:
The spatial and
social
separation of
populations that occurs as a consequence of legal measures.
Demography:
The systematic
analysis of
population.
Discriminatory Shipping Rates:
A
transportation charge levied in
a manner that is inequitable to some shippers, primarily because
of those shippers' location.
Dome:
An uplifted area
of sedimentary rocks
with a downward dip
in all directions; often caused by molten rock material pushing
upward from below. The sediments have often eroded away, exposing
the rocks that resulted when the molten material cooled.
Dry Farming:
A type of farming
practiced in
semi-arid or dry
grassland areas without irrigation using such approaches as
fallowing, maintaining a finely broken surface, and growing
drought-tolerant crops.
Economies of Agglomeration:
The economic
advantages that accrue
to an activity by locating close to other activities; benefits
that follow from complementarity or shared public services.
Economies of Scale:
Savings achieved
in the
cost of production by
larger enterprises because the cost of initial investment can be
defrayed across a greater number of producing units.
Emergent Coastline:
A shoreline
resulting
from a rise in land
surface elevation relative to sea level.
Enclave:
A tract or
territory enclosed within
another state or
country.
Erratic:
A boulder that
has
been carried from
its source by a
glacier and deposited as the glacier melted. Thus, the boulder is
often of a different rock type from surrounding types.
Escarpment:
A long cliff or steep slope
separating two
comparatively level or more gently sloping surfaces and resulting
from erosion or faulting.
Estuary:
The broad lower
course of a river
that is encroached on
by the sea and affected by the tides.
Evapotranspiration:
The water lost
from an
area through the
combined effects of evaporation from the ground surface and
transpiration from the vegetation.
Exotic Stream:
A stream found in
an area that
is too dry to have
spawned such a flow. The flow originates in some moister section.
Extended Family:
A family that
includes three
or more
generations. Normally, that would include grandparents, their
sons or daughters, and their children, as opposed to a "nuclear
family," which is only a married couple and their offspring.
Exurb:
A region or
district that lies outside
a city and usually
beyond its suburbs.
Fall Line:
The physiographic
border between
the piedmont and
coastal plain regions. The name derives from the river rapids and
falls that occur as the water flows from hard rocks of the higher
piedmont onto the softer rocks of the coastal plain.
Fallow:
Agricultural land
that is plowed or
tilled but left
unseeded during a growing season. Fallowing is usually done to
conserve moisture.
Fault:
A fracture in
the
Earth's crust
accompanied by a
displacement of one side of the fracture.
Fault Block Mountain:
A mountain mass
created
either by the
uplift of land between faults or the subsidence of land outside
the faults.
Fault Zone:
A fracture in the
Earth's crust
along which movement
has occurred. The movement may be in any direction and involve
material on either or both sides of the fracture. A "fault zone"
is an area of numerous fractures.
Federation:
A form of
government in which
powers and functions
are divided between a central government and a number of
political subdivisions that have a significant degree of
political autonomy.
Feral Animal:
A wild or untamed
animal,
especially one having
reverted to such a state from domestication.
Fish Ladder:
A series of
shallow steps down
which water is
allowed to flow; designed to permit salmon to circumvent
artificial barriers such as power dams as the salmon swim
upstream to spawn.
Focality:
The
characteristic
of a place that
follows from its
interconnections with more than one other place. When interaction
within a region comes together at a place (i.e., when the
movement focuses on that location), the place is said to possess
"focality."
Functional Diversity:
The
characteristic
of a
place where a
variety of different activities (economic, political, social)
occur; most often associated with urban places.
Geomorphology:
The study of the
arrangement
and form of the
Earth's crust and of the relationship between these physical
features and the geologic structures beneath.
Ghetto:
Originally, the
section of a European
city to which Jews
were restricted. Today, commonly defined as a section of a city
occupied by members of a minority group who live there because of
social restrictions on their residential choice.
Glacial Till:
The mass of rocks
and finely
ground material
carried by a glacier, then deposited when the ice melted. Creates
an unstratified material of varying composition.
Glaciation:
Having been
covered with a
glacier or subject to
glacial epochs.
Great Circle Route:
The shortest
distance
between two places on
the Earth's surface. The route follows a line described by the
intersection of the surface with an imaginary plane passing
through the Earth's center.
Growing Season:
The period from
the
average
date of the last
frost (in the United States, this occurs in the spring) to the
first frost in the fall.
Hazardous Waste:
Unwanted
by-products
remaining in the
environment and posing an immediate potential hazard to human
life.
Hearth:
The source area
of
any innovation.
The source area from
which an idea, crop, artifact, or good is diffused to other
areas.
Heavy Industry:
Manufacturing
activities
engaged in the
conversion of large volumes of raw materials and partially
processed materials into products of higher value; hallmarks of
this form of industry are considerable capital investment in
large machinery, heavy energy consumption, and final products of
relatively low value per unit weight (see Light Industry).
Hinterland:
The area
tributary
to a place and
linked to that
place through lines of exchange, or interaction.
Horizon:
A distinct layer
of soil encountered
in vertical
section.
Humus:
Partially
decomposed organic soil
material.
Hydrography:
The study of the
surface waters
of the Earth.
Hydroponics:
The growing of
plants,
especially vegetables, in
water containing essential mineral nutrients rather than in soil.
Ice Age:
A time of
widespread glaciation (see
Pleistocene).
Igneous Rock:
Rock formed when
molten
(melted) materials harden.
Indentured Labor:
Work performed
according to
a binding contract
between two parties. During the early colonial period in
America, this often involved long periods of time and a total
work commitment.
Indigo:
A plant that
yields a blue vat
dye.
Inertia Costs of Location:
Costs borne by an
activity because it
remains located at its original site, even though the
distributions of supply and demand have changed.
Insular:
Either of an
island, or suggestive
of the isolated
condition of an island.
Intervening Opportunity:
The existence of
a
closer, less
expensive opportunity for obtaining a good or service, or for a
migration destination. Such opportunities lessen the
attractiveness of more distant places.
Intracoastal Waterway System:
A waterway
channel, maintained
through dredging and sheltered for the most part by a series of
linear offshore islands, that extends from New York City to
Florida's southern tip and from Brownsville, Texas, to the
eastern end of Florida's panhandle.
Isohyet:
A line on a map
connecting points
that receive equal
precipitation.
Jurisdiction:
The right and
power to apply
the law; the
territorial range of legal authority or control.
Karst:
An area
possessing
surface topography
resulting from the
underground solution of subsurface limestone or dolomite.
Kudzu:
A vine, native to
China and Japan but
imported into the
United States; originally planted for decoration, for forage, or
as a ground cover to control erosion. It now grows wild in many
parts of the southeastern United States.
Lacustrine Plain:
A nearly level
land area
that was formed as a
lake bed.
Latitude:
A measure of
distance north or
south of the equator.
One degree of latitude equals approximately 110 kilometers (69
miles).
Leaching:
A process of soil
nutrient removal
through the erosive
movement and chemical action of water.
Legume:
A plant, such as
the soybean, that
bears nitrogen-fixing
bacteria on its roots, and thereby increases soil nitrogen
content.
Life Cycle Stage:
A period of
uneven
length
in which the relative
dependence of an individual on others helps define a complex of
basic social relations that remains relatively consistent
throughout the period.
Light Industry:
Manufacturing
activities that
use moderate
amounts of partially processed materials to produce items of
relatively high value per unit weight (see Heavy Industry).
Lignite:
A low-grade
brownish coal of
relatively poor
heat-generating capacity.
Loess:
A soil made up of
small particles that
were transported by
the wind to their present location.
Longitude:
A measure of
distance east and
west of a line drawn
between the North and South Poles and passing through the Royal
Observatory at Greenwich, England.
Maritime Climate:
A climate
strongly
influenced by an oceanic
environment, found on islands and the windward shores of
continents. It is characterized by small daily and yearly
temperature ranges and high relative humidity.
Mediterranean Climate:
A climate
characterized by moist, mild
winters and hot, dry summers.
Mesa:
An isolated,
relatively flat-topped
natural elevation,
usually more extensive than a butte and less extensive than a
plateau.
Mesquite:
A spiny
deep-rooted leguminous
tree
or shrub that forms
extensive thickets in the southwestern United States.
Metamorphic Rock:
Rock that has
been
physically altered by heat
and/or pressure.
Metes and Bounds:
A system of land
survey
that defines land
parcels according to visible natural landscape features and
distance. The resultant field pattern is usually very irregular
in shape.
Metropolitan Coalescence:
The merging of
the
urbanized areas of
separate metropolitan regions; Megalopolis is an example of this
process.
Monadnock:
An isolated hill
or mountain of
resistant rock rising
above an eroded lowland.
Moraine:
The rocks and
soil
carried and
deposited by a glacier.
An "end moraine," either a ridge or low hill running
perpendicular to the direction of ice movement, forms at the end
of a glacier when the ice is melting.
Multilingual:
The ability to
use
more than
one language when
speaking or writing (see Bilingual). This term often refers to
the presence of more than two populations of significant size
within a single political unit, each group speaking a different
language as their primary language.
Municipal Waste:
Unwanted
by-products of
modern life generated by
people living in an urban area.
Nodal Region:
A region
characterized by a
set of places
connected to another place by lines of communication or
movement.
New England:
The northeastern
United
States.
Nuclear Family:
See Extended
Family.
Open Range:
A cattle- or
sheep-ranching area
characterized by a
general absence of fences.
Orographic Rainfall:
Precipitation
that
results when moist air is
lifted over a topographic barrier such as a mountain range.
Outwash:
Rocky and sandy
surface material
deposited by meltwater
that flowed from a glacier.
Overburden:
Material covering
a mineral seam
or bed that must be
removed before the mineral can be removed in strip mining.
Palisades:
A line of bold
cliffs.
Panhandle:
A narrow
projection of a larger
territory (as a
state).
Permafrost:
A permanently
frozen layer of
soil.
Physiographic Region:
A portion of the
Earth's surface with a
basically common topography and common morphology.
Physiography:
Physical
geography.
Piedmont:
Lying or formed
at the base of
mountains; in the
United States, an area in the southern states at the base of the
Blue Ridge Mountains.
Plural Society:
A situation in
which two or
more culture groups
occupy the same territory but maintain their separate cultural
identities.
Plate Tectonics:
Geologic theory
that the
bending (folding) and
breaking (faulting) of the solid surface of the earth results
from the slow movement of large sections (plates) of that
surface.
Platted Land:
Land that has
been
divided into
surveyed lots.
Pleistocene:
Period in
geologic
history
(basically the last one
million years) when ice sheets covered large sections of the
Earth's land surface not now covered by glaciers.
Polynodal:
Many-centered.
Post-industrial:
An economy that
gains its
basic character from
economic activities developed primarily after manufacturing grew
to predominance. Most notable would be quaternary economic
patterns.
Precambrian Rock:
The oldest rocks,
generally
more than 600
million years old.
Presidio:
A military post
(Spanish).
Primary Product:
A product that is
important
as a raw material in
developed economies; a product consumed in its primary (i.e.,
unprocessed) state (see Staple Product).
Primary Sector:
That portion of a
region's
economy devoted to the
extraction of basic materials (e.g., mining, lumbering,
agriculture).
Pueblo:
A type of Indian
village constructed
by some tribes in
the southwestern United States. A large community dwelling,
divided into many rooms, up to five stories high, and usually
made of adobe. Also, a Spanish word for town or village.
Quaternary Sector:
That portion of a
region's
economy devoted to
informational and idea-generating activities (e.g., basic
research, universities and colleges, and news media).
Rail Gauge:
The distance
between the two
rails of a railroad.
Rainshadow:
An area of
diminished
precipitation on the lee
(downwind) side of a mountain or mountain range.
Region:
An area having
some characteristic or
characteristics
that distinguish it from other areas. A territory of interest to
people and for which one or more distinctive traits are used as
the basis for its identity.
Resource:
Anything that is
both naturally
occurring and of use to
humans.
Riparian Rights:
The rights of
water use
possessed by a person
owning land containing or bordering a water course or lake.
Riverine:
Located on or
inhabiting the banks
or the area near a
river or lake.
Scarp:
Also
"escarpment."
A steep cliff or
steep slope, formed
either as a result of faulting or by the erosion of inclined rock
strata.
Scots-Irish:
The North
American
descendants
of Protestants from
Scotland who migrated to northern Ireland in the 1600s.
Secondary Sector:
That portion of a
region's
economy devoted to
the processing of basic materials extracted by the primary
sector.
Second Home:
A seasonally
occupied dwelling
that is not the
primary residence of the owner. Such residences are usually found
in areas with substantial opportunities for recreation or tourist
activity.
Sedimentary Rock:
Rock formed by
the
hardening of material
deposited in some process; most commonly sandstone, shale, and
limestone.
Sharecropping:
A form of
agricultural tenancy
in which the tenant
pays for use of the land with a predetermined share of his crop
rather than with a cash rent.
Shield:
A broad area of
very old rocks above
sea level. Usually
characterized by thin, poor soils and low population densities.
Silage:
Fodder (livestock
feed) prepared by
storing and
fermenting green forage plants in a silo.
Silo:
Usually a tall,
cylindrical structure
in which fodder
(animal feed) is stored; may be a pit dug for the same purpose.
Sinkhole:
Crater formed
when
the roof of a
cavern collapses;
usually found in areas of limestone rock.
Site:
Features of a
place related to the
immediate environment on
which the place is located (e.g., terrain, soil, subsurface,
geology, ground water).
Situation:
Features of a
place related to its
location relative
to other places (e.g., accessibility, hinterland quality).
Smog:
Mixture of
particulate matter and
chemical pollutants in
the lower atmosphere, usually over urban areas.
SMSA - Standard Metropolitan Statistical
Area:
A statistical
unit
of one or more counties that focus on one or more central cities
larger than a specified size, or with a total population larger
than a specified size. A reflection of urbanization.
Soluble:
Capable of being
dissolved; in this
case, the
characteristic of soil minerals that leads them to be carried
away in solution by water (see Leaching).
Space Economy:
The locational
pattern of
economic activities and
their interconnecting linkages.
Spatial Complementarity:
The occurrence
of
location pairing such
that items demanded by one place can be supplied by another.
Spatial Interaction:
Movement between
locationally separate
places.
Staple Product:
A product that
becomes a
major component in trade
because it is in steady demand; thus, a product that is basic to
the economies of one or more major consuming populations (see
Primary Product).
Sustainable Yield:
The amount of a
naturally
self-reproducing
community, such as trees or fish, that can be harvested without
diminishing the ability of the community to sustain itself.
Taiga:
A moist
subarctic
coniferous forest
that begins where the
tundra ends and is dominated by spruces and firs.
Temperature Inversion:
An increase in
temperature with height
above the Earth's surface, a reversal of the normal pattern.
Territory:
A specific area
or
portion of the
Earth's surface; not
to be confused with region.
Tertiary Sector:
That portion of a
region's
economy devoted to
service activities (e.g., transportation, retail and wholesale
operations, insurance).
Threshold:
The minimum-sized
market for an
economic activity. The
activity will not be successful until it can reach a population
larger than this threshold size.
Time-distance:
A time measure of
how far
apart places are (how
long does it take to travel from place A to place B?). This may
be contrasted with other distance metrics such as geographic
distance (how far is it?) and cost-distance (how much will it
cost to get there?).
Township and Range:
The rectangular
system
of
land subdivision of
much of the agriculturally settled United States west of the
Appalachian Mountains; established by the Land Ordinance of 1785.
Transferability:
The extent to
which a good
or service can be
moved from one location to another; the relative capacity for
spatial interaction.
Transhumance:
The seasonal
movement of people
and animals in
search of pasture. Commonly, winters are spent in snow-free
lowlands and summers in the cooler uplands.
Tree Line:
Either the
latitudinal or
elevational limit of normal
tree growth. Beyond this limit, closer to the poles or at higher
or lower elevations, climatic conditions are too severe for such
growth.
Tropics:
Technically, the
area between the
Tropic of Cancer (21-1/2 N latitude) and the Tropic of Capricorn
(21-1/2 S
latitude), characterized by the absence of a cold season. Often
used to describe any area possessing what is considered to be a
hot, humid climate.
Tundra:
A treeless plain
characteristic of
the arctic and
subarctic regions.
Underemployment:
A condition among
a labor
force such that a
portion of the labor force could be eliminated without reducing
the total output. Some individuals are working less than they are
able or want to, or they are engaged in tasks that are not
entirely productive.
Underpopulation:
Economically, a
situation in
which an increase
in the size of the labor force will result in an increase in per
worker productivity.
Uniform Region:
A territory with
one or more
features present
throughout and absent or unimportant elsewhere.
Water Table:
The level below
the land surface
at which the
subsurface material is fully saturated with water. The depth of
the water table reflects the minimum level to which wells must be
drilled for water extraction.
Zoning:
The public
regulation of land and
building use to control
the character of a place.
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