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Hahilat Assessiiicnrs — Our Living Resources 



Landsat Multispectral Scanner (MSS) 

 images of the Dallas-Fort Worth area in 

 1974 and 1989 indicate that in this region 

 urbanization has been the cause of land- 

 cover change (Fig. 1 ). The population of the 

 metropolitan area grew by an estimated 1.25 

 million during this 15-year period. The sub- 

 stantial conversion of cropland, woodlands. 



Landsat MSS Images 



and grasslands to urban land uses resulted 

 from the trend toward migration to sun belt 

 cities and increased job opportunities. 



Landsat MSS images can also display 

 landscape transformations resulting from 

 natural events such as the eruption of Mount 

 Saint Helens in southern Washington and the 

 subsequent recovery of vegetation (Fig. 2). 

 The 1973 image represents the region in its 

 ■"original state." The 1983 image displays 

 the large denuded landscape north of the 



Fig. 1. The 1974 and 1989 Landsat MSS images of Dallas-Fort Worth. Texas. Expanded urban areas are clearly identifiable in the 1989 image and are 

 particularly evident around Dallas-Fort Worth International Airport in the center of the image. 



