Laserfiche WebLink
<br />, ""'03 <br />1'.;,,:,,;r) <br /> <br />Several other forms of support information were used in the study; they <br />included (1) topographic maps, (2) 1 :24,OOO-scale black-and-white and color- <br />infrared aerial photographs, and (3) ground reconnaissance and sampl ing, The <br />specific uses of the data listed here will be included in the discussion of <br />each of the individual remote-sensing applications. <br /> <br />Analysis Techniques <br /> <br />Two techniques were used in the analysis of Landsat data and aerial <br />photographs--photographic interpretation and digital-image processing. Photo- <br />graphic-interpretation techniques (p.45) were used in two phases of analysis. <br />In the first phase, photographic interpretation of the 1 :24,OOO-scale black- <br />and-white and color-infrared photographs was used in conjunction with ground <br />information to: (1) Locate and identify surface features for use in defining <br />training sets for supervised classification techniques (p. 46), and (2) to <br />provide information for subsequent evaluation of Landsat classification <br />results. In the second phase, photographic-interpretation techniques were <br />used directly in the analysis and classification of Landsat images, Oigital- <br />image processing (p, 45) for analysis and classification was applied to: (1) <br />Landsat digital data,and (2) digitized 1:100,OOO-scale color and color-infra- <br />red photographs. Digital-image processing was conducted using the Image-l00 <br />Systeml and Interactive Digital Image Manipulation System (IDIMS) (p. 47), <br /> <br />APP LI CAT IONS <br /> <br />Land-Use Classification <br /> <br />Large variations in altitude (5,000-12,000 ft or 1,500-3,700 m) and <br />precipitation (9-50 in. or 230-1,300 mm) produce a wide range of land-use <br />categories in the Yampa River basin. Timber harvesting and grazing represent <br />the largest areal land use; 89 percent of the basin's area is devoted to <br />these activities (Colorado Water Conservation Board and U,S. Department of <br />Agriculture, 1969). Despite the lesser areas involved, farming and energy- <br />resource development are major contributors to the regional economy (Udis and <br />Hess, 1976). In some areas, agricultural land-use patterns tend to shift <br />back and forth between grazing and dryland farming of small grains in <br />response to prices in the wholesale market, The type of land use and the <br />land-reclamation and conservation practices used can have a pronounced effect <br />on the amount of soil erosion that occurs in a given area. This is especial- <br />ly true for many of the areas of dryland farming and surface mining of coal <br />in the Yampa River basin (Routt County Soil Conservation District, 1977), <br />These areas are potential contributors of considerable quantities of sedi- <br />ments to the streams that drain them. Unsound grazing and timber-management <br />practices also could result in relatively large erosion rates in certain <br />areas. <br /> <br />does <br /> <br />lThe use <br />not imply <br /> <br />of trade names in this report is for identification only and <br />endorsement by the U.S. Geological Survey. <br /> <br />7 <br />