抄録
We surveyed soil erosion and slope failure in a grazed pasture in South Hokkaido using digital surface model (DSM) for geomorphic analysis, also, estimated about adaptation to a monitoring in a grazed pasture using DSM. In this study, DSMs were extracted by multi-temporal aerial photographs and digital photogrammetric technique. Digital elevation model (DEM) was extracted by contour map of paper for accuracy validation of DSM absolute accuracy. As a result of DSM accuracy evaluation on the basis of DEM, in all the ages, root mean square deviation of height direction were with satisfactory accuracy. Using extracted multi-temporal DSMs, large-scale soil erosion and slope failure were able to be performed. In addition, growths of grass were able to be grasped. However, it was difficult to extract the minute geomorphic change formed in the grazed pasture. Application of photogrammetric technique to monitoring of grazed pasture definite showed may be able to contribute to preservation of a grazed pasture, and maintenance.