Abstract ID: 278

Height Above the Nearest Drainage, a new terrain descriptor for mapping terra-firme rainforest environments in Amazonia using SRTM data

Optical remote sensing imagery (such as Landsat and CBERS) can show spectral properties of forest canopy in detail, but rarely allows for finding accurate correspondence of canopy features with soils and hydrology. The understanding of land surface processes at finer scales needs accurate topographic data, now available with the Shuttle Radar Topographic Mission (SRTM) data. These data reveal the feature-rich relief of lowland rainforests, improving the ability to map rainforest environments through many quantitative terrain descriptors. In this paper we present the development of a new terrain descriptor called HAND (Height Above the Nearest Drainage), based on SRTM-DEM data. This descriptor obeys the physical principle of soil draining potential, and measures the vertical distance of each basin point to the nearest drainage using the local drain directions. The application of the HAND descriptor in classifying the terrain within a monitored hydrological basin in central Amazonia revealed strong correlations between soil water conditions, like classes of water table depth, and topography.

Session:  Biodiversity - Modeling biodiversity, present and future. (A)

Presentation Type:  Oral