Timberline change detection using topographic map and satellite imagery

• Main Authors: Sushma Panigrahy, D Anitha, M M Kimothi, S P Singh
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2010
• Subjects: Alta; Nanda; Referencia; Tundra
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1089.7640; http://www.tropecol.com/pdf/open/PDF_51_1/Jour.10.pdf

Abstract: High altitude ecosystems, defined by low temperatures, are known to react sensitively to climate warming. This study reports vegetation ingression and land cover changes in an area of Nanda Devi Biosphere Reserve in Central Himalaya using satellite imagery of 1986, 1999 and 2004. The topographic map of 1960 was taken as benchmark. The SRTM DEM data was used to extract information on elevation, slope and the aspect. The March 1986 satellite imagery showed snow, glaciers and scree as dominant land cover types with a few dense vegetation patches. The 1999 imagery showed marginal increase in vegetation cover while 2004 imagery revealed >20% increase in the vegetation cover and drastic reduction in snow cover, thereby showing vegetation ingression in erstwhile snow/ice areas. The elevation contours, overlaid on the 2004 imagery, showed the timberline at 4300 m, the alpine scrub line at 4900 m and the tundra vegetation line at 5300 m above m.s.l. The topographic map of 1960 showed scrub, scattered trees and timberline between 3900 and 4000 m above m.s.l. The study indicates rapid recession of glaciers and snow cover and ingression by vegetation probably due to global warming related rise in temperature. Resumen: Los ecosistemas de alta elevación, definidos por temperaturas bajas, son conocidos por reaccionar de forma sensible al calentamiento climático. En este estudio se reportan la intrusión de la vegetación y los cambios en cobertura del suelo en una área de la Reserva de la Biosfera Nanda Devi en los Himalaya Centrales, usando imágenes satelitales de 1986, 1999 y 2004. Se tomó el mapa topográfico de 1960 como punto de referencia. Se usaron datos del modelo digital de elevación SRTM para extraer información sobre la elevación, pendiente y orientación. Las imágenes satelitales de marzo de 1986 mostraron que los tipos de cobertura terrestre dominantes fueron nieve, glaciares y pedreras, con unos pocos parches de vegetación densa. Las imágenes de 1999 mostraron un incremento marginal en la cubierta ...