TITLE:
Soil Mapping of a Small Watershed in a Brazilian Savanna Biome: A Semi-Automatic Approach
AUTHORS:
Larissa Ane de Sousa Lima, Adriana Reatto, Henrique Llacer Roig
KEYWORDS:
Semi-Automatic Mapping, SRTM, Morphometric, Pedological Maps
JOURNAL NAME:
Journal of Geographic Information System,
Vol.6 No.2,
April
4,
2014
ABSTRACT: The objective of this
work is to propose a semi-automatic methodology for the creation of a semidetailed
to detailed watershed’s soil map. This methodological proposal is based on the
traditional method (field work and photo interpretation) and on morphometric
variables analysis, using data originated from the Digital Elevation Model
(DEM) of the Shuttle Radar Topography Mission (SRTM) program. The steps taken
through this methodological proposal were the identification of the
hydromorphic areas boundaries through interpretation of aerial
orthophotographs; the compartmentalization of the relief through color
composition techniques using the morphometric variables—slope, altimetry and
horizontal curvature; the development of a pedological database based on data
gathered in the field; the elaboration of a preliminary soil map based on the
compartmentalized relief and on the dataset of the soils sampled in the field;
the elaboration and adjustment of the final soil map according to the
interpretation of aerial photographs and also the physical and chemical
analyses of the soils. This semi-automatic methodology demonstrated improved
efficiency in defining the soil units, reducing operation time and subjectivity
of the process, thereby contributing to the systematization of soil mapping at
watershed level in scale 1:50,000, as well as, promoting better knowledge
between the relation of the geomorphic and soil variables in the Brazilian
Savanna Cerrado.