Geometric accuracy of LANDSAT-4 MSS image data

Analyses of the LANDSAT-4 MSS image data of North Georgia provided by the EDC in CCT-p formats reveal that errors of approximately + or - 30 m in the raw data can be reduced to about + or - 55 m based on rectification procedures involving the use of 20 to 30 well-distributed GCPs and 2nd or 3rd degree polynomial equations. Higher order polynomials do not appear to improve the rectification accuracy. A subscene area of 256 x 256 pixels was rectified with a 1st degree polynomial to yield an RMSE sub xy value of + or - 40 m, indicating that USGS 1:24,000 scale quadrangle-sized areas of LANDSAT-4 data can be fitted to a map base with relatively few control points and simple equations. The errors in the rectification process are caused by the spatial resolution of the MSS data, by errors in the maps and GCP digitizing process, and by displacements caused by terrain relief. Overall, due to the improved pointing and attitude control of the spacecraft, the geometric quality of the LANDSAT-4 MSS data appears much improved over that of LANDSATS -1, -2 and -3

Water Quality in the Headwaters of the Upper Oconee Watershed

Proceedings of the 2001 Georgia Water Resources Conference, April 26 and 27, 2001, Athens, Georgia.Development in the Southern Piedmont of the USA is increasing urban demand for clean water for recreation and municipal supplies. Agricultural production is perceived to be a non-point source of pollution in this region. To effectively target efforts to reduce agricultural pollution, we are working to estimate the impact of conservation practices and to develop water-sampling strategies for identifying key areas for conservation efforts. Nine sites were selected for sampling surface water quality in the headwaters area of the Upper Oconee Watershed of Georgia. Significant variation in water quality was observed among the 9 sites. In some cases, high levels of N and P may have been the result of holding ponds associated with agricultural processing or confined animal operations located adjacent to the water body and near the sample sites. Dilution of upstream impacts was apparent at downstream sites particularly with the samples representing the Middle Oconee River.Sponsored and Organized by: U.S. Geological Survey, Georgia Department of Natural Resources, Natural Resources Conservation Service, The University of Georgia, Georgia State University, Georgia Institute of TechnologyThis book was published by the Institute of Ecology, The University of Georgia, Athens, Georgia 30602-2202. The views and statements advanced in this publication are solely those of the authors and do not represent official views or policies of The University of Georgia, the U.S. Geological Survey, the Georgia Water Research Institute as authorized by the Water Resources Research Act of 1990 (P.L. 101-397) or the other conference sponsors