Monitoring vegetation regeneration and deforestation using change vector analysis: Mt. St. Helens study area

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Conference Paper


A sophisticated method for monitoring land-cover change in a highly disturbed landscape involved change vector analysis of multitemporal Kauth-Thomas transformation data. Landsat TM data acquired after the 1980 eruption of Mt. St. Helens (1986 and 1996) were analyzed in this study. Topographic effects from the rugged terrain were removed by regressing a generated hillshade image against each band to estimate illumination variation. The estimates were subtracted from each image to generate variation-free data. The images were then transformed into Kauth-Thomas features representing brightness and greenness to enhance landscape features and reduce data redundancy. Change vector analysis allowed for land-change classification without defined calibration sites. The technique produced images of change direction and magnitude between two dates based on the inputs of brightness and greenness. The direction of change indicated whether a landscape had experienced deforestation, reforestation, or remained persistent. Magnitude indicated to what degree the change occurred. The results of the study show that intensive vegetation regeneration occurred within the blast-zone between 1986 and 1996. The method provided a clear-cut process for classifying and quantifying vegetation change. © 2005 by the American Society for Photogrammetry and Remote Sensing.

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American Society for Photogrammetry and Remote Sensing - Annual Conference 2005 - Geospatial Goes Global: From Your Neighborhood to the Whole Planet

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deforestation, luminance, reforestation, remote sensing, vegetation