Valley Bottom Constricted (Thiessen Polygon Constricted)

  • Thiessen polygons - Polygons generated from a set of sample points. Each Thiessen polygon defines an area of influence around its sample point, so that any location inside the polygon is closer to that point than any of the other sample points. Thiessen polygons are named for the American meteorologist Alfred H. Thiessen (1872-1931).

  • Constricted Valley - Valley defined by the anthropomorphic impedances such as roads, bridges, trails, levees, neighborhoods etc.

  • Impervious Surface - any surface in the landscape that cannot effectively absorb or infiltrate rainfall (examples: roads, driveways, parking lots and rooftops)

  • Total Polygon Acreage - Total area of polygon in acres.

  • Forest Acreage - Acreage of forest land cover/land use within polygon.

  • Crop Acreage - Acreage of crop land cover/land use within polygon.

  • Impervious Surface Acreage - Acreage of impervious surface land cover/land use within polygon.

  • Water Acreage - Acreage of water land cover/land use within polygon.

  • Sparsely Vegetated Acreage - Acreage of sparsely vegetated land cover/land use within polygon.

  • Grass Acreage - Acreage of grass land cover/land use within polygon.

  • % Forest - Percent of forest land cover/land use within polygon.

  • % Crop - Percent of crop land cover/land use within polygon.

  • % Impervious Surface - Percent of impervious service land cover/land use within polygon.

  • % Water - Percent of water land cover/land use within polygon.

  • % Sparsely Vegetated - Percent of sparsely vegetated land cover/land use within polygon.

  • % Grass - Percent of grass land cover/land use within polygon.