3D mapping of lowland coastal peat domes in Indonesia

Extent and thickness of peat deposits in Indonesia are poorly constrained although both are important factors in regulating peat use and in planning peat conservation. Innovations for mapping the extent and thickness of peat deposits were developed and tested on two highly disturbed peat domes on the islands of Sumatra and Kalimantan (Borneo), Indonesia. Peat dome surface topography was mapped by transforming radar Digital Surface Models (DSM) to Digital Terrain Models (DTM) using ortho-photogrammetric techniques and cadastral standard Ground Control Points (GCPs). Soil core samples were collected along gradient transects to determine the peat base topography. A digital peat base model (DPBM) was generated by fitting a surface to the peat base elevation points in soil cores. Combining the peat surface DTM with the peat base DPBM provides a three-dimensional model of peat extent and thickness. Maps derived from these models can inform a ‘whole of dome’ approach to resolving competing land use goals, reducing regional smoke hazard and mitigating greenhouse gas emissions. The DPBM makes a critical contribution to accurate peat dome mapping and successful peat management on Indonesia’s coastal peatlands and in any other locations where peat has formed on an undulating irregular soil surface.