Applications of GIS for Investigation of Reservoir Sediments

摘要

To maintain continuing uses of aging reservoirs, dredging has been one of the most common means. Based on the difference of the recently surveyed and the original topographical maps, an image of sediment depth was developed displaying variations of deposits in the reservoir. Then, sixty sites were selected to for sediment sampling by a gravity corer, sixty centimeters long and eight centimeters in diameter. Each sample was bagged and marked with its geographical location using a global positioning system with a detailed map. Samples were dried and analyzed by the mechanical sieve analysis to develop particle distribution curves. Particle sizes at sampling locations, assumed to be spatial variables, were interpolated to form the images to which the map algebra can be applied to derive the geographical distributions of sediment gradation and uniformity. The resulting information provided the guidance to determine how and where to dredge in order to properly form wetlands using dredged materials at varied locations within the same reservoir.