FWS Submissions

Two-dimensional imagery from satellites and airborne sensors has been an invaluable resource to the scientific understanding of ecosystems. With technologies such as lidar and Interferometric Synthetic Aperture Radar (IFSAR), a third vertical dimension has been added to these data.  Forest structural parameters such as tree density, height, and arrangement have a substantial effect on ecosystem functions and health, and the ability to have a more complete understanding of ecosystems over large areas has created a demand for such data.

To facilitate the location of abandoned oil wells, orthomosaic images were created from historical aerial photos acquired in 1972 and 1969. Agisoft Photoscan was used to create camera calibration files and align the 15 images from 1972 and 38 from 1969. The images were georeferenced, identifying features from the historical imagery present in current imagery. The coordinates of these features were used to create markers in Photoscan to reference the images, creating an accurate photomosaic with 2- to 4-meter error.