Untitled Document

Terrain Analysis (cited from Wikipedia)

Terrain

Terrain , or relief , is the third or vertical dimension of land surface . When relief is described underwater , the term bathymetry is used. Topography has recently become an additional synonym, though in many parts of the world it retains its original more general meaning of description of place.

Terrain is used as a general term in physical geography , referring to the lie of the land . This is usually expressed in terms of the elevation , slope , and orientation of terrain features. Terrain affects surface water flow and distribution. Over a large area, it can affect weather and climate patterns

Importance of terrain

The understanding of terrain is critical for a number of reasons.

The terrain of a region largely determines its suitability for human settlement: flatter, alluvial plains tend to be better farming soils than steeper, rockier uplands.

In terms of environmental quality, agriculture , and hydrology , understanding the terrain of an area enables the understanding of watershed boundaries, drainage characteristics, water movement, and impacts on water quality . Complex arrays of relief data are used as input parameters for hydrology transport models (such as the SWMM or DSSAM Models ) to allow prediction of river water quality .

Understanding terrain also supports on soil conservation , especially in agriculture. Contour plowing is an established practice enabling sustainable agriculture on sloping land; it is the practice of plowing along lines of equal elevation instead of up and down a slope.

Terrain is militarily critical because it determines the ability of armed forces to take and hold areas, and to move troops and material into and through areas. An understanding of terrain is basic to both defensive and offensive strategy.

Terrain is important in determining weather patterns. Two areas close to each other geographically may differ radically in precipitation levels or timing because of elevation differences or a " rain shadow " effect.

Characteristics of terrain

Land surface may appear fractal , anisotropic and non-periodic. However, the land surface is controlled by the underlying geologic structures and the climate affecting the surface. Land surface can be rather smooth but also very rough and dissected and complex. Areas of land surface that have relatively homogeneous morphometric properties are called landforms .