Category: GIS

Digital Terrain Modeling – Aspect models

In digital terrain modeling the Aspect of a surface refers to the azimuth to which a slope is orientated. The aspect or orientation of a slope can produce very significant influences on it, so it is important to know the aspect of the plane as well as the slope.Together the slope combined with the aspect of the surface can virtually define the surface plane completely in digital terrain modeling

Example of an Aspect Map

This image is an Aspect Model that I derived from a digital elevation model (DEM) of Lismore, Nova Scotia. The aspect values of the slopes of the DEM are represented in the model by a 0-255 grey scale color ramp. Click here to learn a little more about Aspect Models and how the image below was created.

Slope

The slope or the gradient of a straight line within a Cartesian coordinate system is known as the measure of how steep a line is relative to the horizontal axis. In terrain modeling we generally model an entire surface and not just one line so we need to calculate the slope of a best fit surface plane (which is made of lines). Together the slope combined with the aspect of the surface can virtually define the surface plane completely.

Example of a Slope Map

The image here is a Slope Model that I derived from a digital elevation model (DEM) of Lismore, Nova Scotia.

GIS Spatial modeling for Kejimkujik National Park

This technical report details the methodologies and issues that were encountered with a Spatial GIS vegetation database and GIS Spatial modeling project at the Applied Geomatics Research Group (AGRG) during the summer of 2004 that involved generating a spatial geographic database for Jeremy’s Bay Campground of Kejimkujik National Park and Historic Site. High resolution aerial photography acquired from a previous AGRG aerial photography mission was used along with extensive data collected during a Rapid Vegetation Assessment survey and a detailed forest stand interpretation.