ABSTRACT
Peatland mapping is an important national agenda in Indonesia, due to human disturbances and other prominent issues related to conservation and environment. The exposure of mineral soils underlying these peatlands can further increase potential environmental problems when it contains acid sulfate soil (ASSoils - FeS2), harmful mineral when exposed to oxygen. Remote sensing applications on peatland mapping are commonly utilized to identify its extent, but never examined its ASSoils potential area. This study aims: 1) to map the coastal ASSoil occurrence probability based on a hybrid remote sensing and hydrogeomorphical approaches and 2) to examine the ability of remote sensing in assisting the development of digital ASSoils mapping in tropical peatland. This study utilized the legacy peatland data of Kubu Raya and Ketapang areas provided by the Indonesian Ministry of Agriculture. The hybrid remote sensing image analysis approach consists of a combination of visual interpretation and digital image analysis. Multi-temporal satellite imageries (Landsat 8, Sentinel-2) representing rainy and dry seasons were processed to derive wetness, vegetation density indices and landcover maps. Soil characteristics data included the thickness of peat, underlying materials, and ASSoils distributions. Processed hydrological and topographical data produces maps of tidal, salinity, and sea water intrusion and micro-elevation accordingly. Visual remote sensing image interpretation was conducted to identify existing coastal landforms. Both intermediary maps are associated to the field survey data and are used to determine the peatland ASSoil hydro-geomorphology units. The development of this digital ASSoils mapping is important to underpin the strategic regional and national planning in the peatland environment.
