Changing Landscapes – Charleston (OIMB), Oregon

This summer has involved a good bit of traveling with several excursions to the Oregon Institute of Marine Biology where I have been teaching several workshops.  This week I taught a class on using the GIS program QGIS.  The class covered georeferencing an old (1939) photograph of the Charleston, Oregon area and then creating some new content based on differences between the old and a current images.  The picture above shows the old photograph digitally rotated and stretched such that it would directly overlay known the same area in the current image (supported by Google Satellite Imagery). In this particular case, I had the class create a set of polygons based on sandbars visible in the old photograph.  We then used the program to calculate the area of the sandbars.  We also created a set of points referring to salinity data of water in the estuary and used the program to classify and color-code the points such that they indicated the salt concentration along a gradient of mesohaline salt in the estuary to a polyhaline concentrations in the ocean.