農業立地分析のためのALOS全世界デジタル3D地形データ利用優位性の検討

抄録

We examined the newly published high spatial resolution digital elevation data, ALOS 3D World Topographic Data (AW3D), for application of the analysis of locational condition of agriculture mainly compared with ASTER Global Digital Elevation Model (GDEM). The study site was selected in the middle part of Burkina Faso, where topographic condition was consisted of gentle slopes even around watershed boundaries and bottom of valleys. Examination was focused on sloping features and river/watershed systems as comparing elevation profile along transect line measured by handy GPS. As a result, GDEM contained random deviations with amplitude of several meters, which might induce apparent high degree of slopes. On the other hand, AW3D was proved to fit optimally with profile of GPS measured data and did not show large deviation as appeared in GDEM profile. River course and watershed boundary obtained from AW3D and GDEM were not identical and GDEM might produce unrealistic river course in close up scale map. However in regional scale, both AW3D and GDEM produced river course and watershed boundary with similar morphological pattern.