grapho-, graph-, -graph, -graphy, -grapher, -graphia

A major division of plant science which is concerned with all aspects of the spatial distribution of vegetation: Geographical botany, plant geography, and phytogeography all involve the study of the spatial distributions of plant life and of the environmental relationships which may influence these distributions.

Plant geography has emphasized the mapping of such regions and the interpretation of the terms of environmental (ecological) influences.

The areas of Phytogeography and zoogeography do not necessarily exist together in the same place, because there are barriers and factors that affect their growth and arrangements which are often different for plants and for animals.

The point on which a given area on the earth would balance, if the earth were a plate of uniform thickness.

A deep steep-walled half-bowl-like recess or hollow, variously described as horseshoe-shaped, crescent-shaped, or semi-circular in form, situated high on the side of a mountain and commonly at the head of a glacial valley and produced by the erosive activity of a mountain glacier.

It often contains a small round lake, and it may, or may not, be occupied by ice or snow.

1. The world-wide system of latitude and longitude used to define the location of any point on the earth's surface or to designate both geodetic coordinates and astronomical coordinates.
2. The quantities of latitude and longitude which define the position of a point on the surface of the earth with respect to the reference spheroid.

1. Theory was developed or formulated by the American geographer and geomorphologist, William Morris Davis (between 1884 and 1934), who modeled the formation of river-eroded landscapes.

This theory suggests that landscapes go through three stages of development (youth, maturity, and old age) and indicates that the rejuvenation of landscapes arises from tectonic uplift of the land.

In the "youthful stage", under the influence of tectonic uplifts, there appears a mountain relief, which is dissected through erosion (the washing out of rocks by rivers) into deep, narrow valleys and sharp-peaked ridges.

With the dissection by streams, the area would reach maturity and, ultimately, would be reduced to an old-age surface called a peneplain (gently undulating, almost featureless plain), with an elevation near sea level.

The model developed by Davis, though important in historical context, is currently considered only a first approximation.

Developments in the sciences of geology and geomorphology, especially the plate tectonics revolution of the 1960's and 1970's, have confirmed the preliminary nature of the model.

A theory stating that human culture and activity can be explained by the geographical circumstances or conditions in which they are found.

For example, there is the idea that a desert environment will produce a nomadic culture because desert terrain makes it easier for movement and the lack of consistent rainfall stimulates such movement.

The physical character and distribution of natural resources on the face of the earth.

The fundamental differences between land and ocean, latitudinal differences in insulation, spatial variations in receipts of precipitation, and patterns of geological composition, and deformation of the earth's crust together provide the basis for distinguishing definite geographical patterns of resource availability through out the world.

1. A computer system specialized for the storage, manipulation, and presentation of geographical information; such as, topography, political subdivisions, geology, vegetation, flood plains, etc.
2. A computerized system which relates and displays data collected from a geographic entity in the form of a map.

The ability of a geographical information system to overlay existing data with new information and display it in color on a computer screen and is used primarily to conduct analyses and make decisions related to geology, ecology, land use, demographics, transportation, and other domains, most of which relate to the human use of the physical environment.

Through this process of geocoding, the geographic data from a database is converted into images in the form of maps.

1. A British unit of length equivalent to 1,853.18 meters (6,082 feet) , which was replaced by the international nautical mile in 1970.
2. A former name for nautical mile (sea mile) or a unit of length used in sea and air navigation, based on the length of one minute of arc of a great circle; especially, an international and U.S. unit equal to 1,852 meters (about 6,076 feet).
3. A unit of length in the US Customary System, used in air and sea navigation and equal to 6,076 feet or 2,025 yards (1,852 meters).

A plot (measured area of land) in which positions are displayed in terms of actual geographical position; as opposed, for example, to a relative plot; the successive positions of a craft relative to a reference point, which is usually in motion.

1. That point on the earth or a location on the surface of a planet at which a given celestial body is in the zenith at a specified time.
2. Any position on the surface of the earth defined by means of its geographical coordinates, either astronomical or geodetic; or expressed in terms of latitude and longitude, either geodetic or astronomical.

A representation of the globe constructed on a plane with lines representative of and corresponding to the meridians and parallels of the curved surface of the earth.

1. A spatial distribution of a species (group of interbreeding organisms that do not ordinarily breed with members of other groups) in which the geographic ranges of species often fluctuate over time.
2. The total area occupied by a population.
3. The extreme distance at which an object or light can be seen when limited only by the curvature of the earth and the heights of the object and the observer.

1. A procedure in which search areas are assigned by geographical areas or sectors.
2. An orderly arrangement of lines in which an area is defined in relation to one or more geographical points on the earth.