『Abstract
　Studying spatial and temporal variation of soil loss is of great importance because of global environmental concerns. Understanding the spatial distribution of soil erosion and deposition in the high-cold steppe is important for designing soil and water conservation measures. Measured ¹³⁷Cs losses (Bq m^-2) from long-term high altitude (4,000 m above sea level) watershed plots on the Qinghai - Tibet plateau and derived soil erosion estimates (Mg ha^-1 year^-1) were significantly correlated to directly measured soil losses from the same plots, over the same period (1963-2005). The local reference inventory was estimated to be 2,468 Bq m^-2. The result of analyzing ¹³⁷Cs distribution and its intensity in the soil profiles in this area shows similarities to ¹³⁷Cs distribution in other areas. ¹³⁷Cs is basically distributed in the topsoil layer of 0-0.3 m. Soil erosions vary greatly in the entire sampled area, ranging from 5.5 to 23 Mg ha^-1 year^-1, with an average of 16.5 Mg ha^-1 year^-1 which is a moderate rate of erosion.

Keywords: The ¹³⁷Cs method; Surface runoff; Soil erosion; spatial distribution; Radionuclide』

Introduction
Study area
Reference site
Methodology
　Sample site and soil sampling
　¹³⁷Cs content analysis
　Conversion ¹³⁷Cs levels to erosion rates
Results and discussion
Conclusions
Acknowledgments
References