A Geomorphic Study of Man-Induced Soil Erosion in the Sagarmatha (Mount Everest) National Park, Khumbu, Nepal: Report on the Activities of the UNU/MAB (Nepal) Mountain Hazards Mapping Project, Phase II

Abstract

The degradation of the Himalayan environment, supposedly a consequence of contemporary deforestation and overgrazing, is a much publicized though poorly understood phenomenon. The past decade has produced a copious literature linking population pressures with increased deforestation, soil erosion, landslides, and siltation of water courses-(e.g., Eckholm, 1975a, 1975b, 1976; Sterling, 1976; Rieger, 1976). The Kingdom of Nepal has been frequently cited as a prime example where the above factors have resulted in widespread environmental degradation. These assumptions, supported by little reliable data, have nevertheless provided the basis for many ongoing development policies in the Himalaya. A general uncertainty regarding the actual impacts of man and his activities upon the environment has only recently been acknowledged by the scientific and development communities (Ives, 1984; Thompson and Warburton, 1985a). In 1984, the United Nations University (UNU) funded a 9-month project in the Sagarmatha (Mount Everest) National Park of Nepal with the specific objective of quantifying man-induced rates of soil erosion, thereby removing some of the uncertainty surrounding the forementioned assumptions in at least one Himalayan region. The project represents the geoecological component of the Mountain Hazards Mapping Project, Phase II (Khumbu), with the actual hazard mapping fieldwork completed in 1982 by colleagues from the University of Berne (Ives and Messerli, 1981; Zimmermann et al., this issue, pp. 29-40). Sagarmatha National Park was chosen to represent the High Mountain study region because of reportedly high maninduced soil erosion rates; the availability of relevant literature; and access to maps and aerial photographs. Members of the expedition included Alton Byers (team leader); Elizabeth Byers (geohydrologist); Khadga Basnet (ecologist); Narendra Raj Khanal (cultural geographer); Khancha Lama (field technician); and Pembra Sherpa (headquarters field assistant). Dr. Colin E. Thorn (Department of Geography, University of Illinois) assisted the team with its start-up activities in March, 1984. Dr. J. D. Ives (Department of Geography, University of Colorado) and Professor S. R. Chalise (Member Secretary, MAB/Nepal) provided valuable moral, technical, and material support throughout the project's duration.