Geographic Information Systems (GIS) are a leading technology in the natural resources profession. This technology results from the organization of geographic information into computer database and analysis software which allows for statistical analysis, calculations, custom map production, and many other manipulations to support planning, development, and research projects. Geographic information is any data referenced to a specific geographic location or extent and is usually gathered by one of the following techniques:
- Geographic Positioning Systems (GPS) devices record geospatial data as points, lines, and polygons which then may be imported into a computer database for later viewing and manipulation.
- Digitization and geo-referencing of legacy map products such as land surveys, civil engineering diagrams, or other analog constructions.
- Digital imagery such as aerial photos or satellite images are included in GIS databases by assigning individual pixels a geographic extent and nominal value. GIS data originating from digital images is known as "raster" data.
An example of GIS Use:
GPS devices may be used to record the spatial location of campsites (points) and the path of trails (lines). Once downloaded into a computer-based GIS database, the campsites can be assigned to user-created categories of "campsite size" or "campsite use" by entering classifying attributes such as "large" or "small", "heavily used" or "lightly used". Most GIS programs allow the user to formulate spatial analysis queries using this location-based data. An example of spatial analysis would be to use the program to calculate the average distance of campsites (points) from the trails (lines). Information resulting from spatial analysis is extraordinary useful for creating maps, reporting area statistics, and tracking changes over time. Many land managers have recognized the power of GIS and are increasingly using spatial analysis as a key element in formulating and evaluating management policies.
Types of GIS Software
ESRI's ArcGIS software is the most widely-used commercial GIS program. ESRI offers their software in several packages, ranging from the most basic (ArcView) to the most complex (ArcInfo). Training in ArcGIS is available directly through ESRI and as part of GIS classes offered by technical training centers, colleges and universities. To become familiar with ArcGIS on your own time, download and try out ArcReader, a free GIS viewer program available from ESRI.
The annual licensing fees for ArcGIS is often a significant expense for many individuals and organizations such that many have adopted open-source GIS software. Many of these free GIS programs are available and they greatly vary in ease of use, features, and complexity. Some examples of open-source GIS include Quantam GIS (QGIS) and GRASS. An expansive list of available free GIS programs is available at Wikipedia.
Certification
Many technical training centers, community colleges, and universities offer classes, certificate programs, associate's, or bachelor's degrees in GIS. These programs provide extensive training and experience in GIS software. Formal GIS training is a great advantage to the job seeker as many employers within the natural resources field prefer or require GIS certificates or degrees for applicants to be considered as highly qualified job candidates.
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