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Photointerpretation and Cartography Research
Return to Spatial Analysis |
U.S. Department of the Interior |
U.S. Geological Survey
URL: http://www.nwrc.usgs.gov/about/capabilities/photogra.htm
Web Site Technical Issues: nwrcweb@usgs.gov
Web Site Content Questions: nwrcinfo@usgs.gov
Page Last Modified: Monday, 31-Dec-2012 11:31:21 EST
The National Wetlands Research Center uses traditional and innovative cartographic
techniques to spatially represent ecological, biological, and other data derived
from current and historical aerial photography, habitat interpretation, and
map transformation. Aerial photography is the primary data source for information
on wetland and associated environments, and the film types include black and
white, natural and false color (CIR-color infrared). Various scales of high
altitude and low-level photography are obtained through private and government
contractors, including NASA which operates the ER-2 reconnaissance aircraft.
In some cases, historical photography is obtained from other government agencies
and private sources. Photointerpreters use stereoscopes to determine baseline
information on wetlands, including the location and extents of wetlands, upland,
and seagrass habitats from the photography. This data is transferred to base
maps and subsequently digitized for computer analysis. Newer stereoscopic technology allows technicians to digitize and update vector data directly on screen. Extensive field work,
including global positioning system (GPS) surveying, combined with careful
compliance to established mapping conventions and accuracy standards result
in some of the most accurate, up-to-date, and informative maps available.
Ecologists use this information to analyze the status and trends of coastal
wetlands, to monitor resource management projects, and this information is
used by other researchers at NWRC, as well as various local, state, and federal
agencies, and the general public.