Environmental Products
AAI uses its QSC application to retrieve the bottom material and water quality information from a spectral image. The retrieved water quality information for each pixel defines the suspended sediment concentration of the water column, while the bottom spectrum defines the bottom spectral reflectance for each pixel. AAI's iCee™ atmospheric correction, Mixed Material Classifier and Material Identifier are used to automatically retrieve and identify component bottom materials in mixed pixels. This allows accurate assessment of sediment type and cover extent. The suspended sediment concentrations provide complimentary sediment loading, dynamics, and transport information for sediment budget estimations.
QuickBird image of a river undergoing active sediment deposition. Suspended sediments (center) can be seen entering the river from several small tributaries. Sediments are being deposited at a rate that can be determined from the indicated concentrations. Accumulating bottom silt deposits (right, light tan) are rapidly filling in the dredged channel (dark tan), creating a navigational hazard.
Shallow-water sediment budget: Changes in sediment deposition (above) and bottom material patterns (below) in the Mississippi River Delta, Louisiana after 24 years. Comparison of the image-retrieved suspended sediment concentrations reveals an apparent spatial contraction of the source area in 2008 (above right) relative to 1984 (above left), even though local sediment concentrations were higher in the 2008 image. Similarly the bottom sediments (green) on 19 May 2008 (below right) are less uniform and more contracted in spatial extent than they were in the earlier 25 March 1984 date. Red corresponds to areas of active erosion, while the purple-blue area is deeply eroded.
Evidence for possible bank erosion is seen in the near Steer Horn Neck on the Patuxent River, MD (indicated by a red box in the image above). Subpixel analysis processing using AAI's Mixed Material Classifier reveals a cluster of sup-visual bank erosion features (tan) indicated by the red arrows (below).
Environmental Products List