Soil parent material delineation using MODIS and SRTM data

Abstract

A digital mapping procedure was developed and tested to support the SOTER (SOil and TERrain digital database) database development. The SOTER mapping unit delineation is based on terrain and parent material information. Terrain information can be derived from SRTM data, but parent material information is often difficult to obtain. Legacy data are scarce and they are not always easily accessible. A procedure is needed to derive parent material information with limited legacy data support. The aim of this study was to develop a robust, remote sensing (MODIS and SRTM) based procedure to delineate soil parent material (PM) classes for small scale soil mapping applications. This quantitative procedure aimed to maintain the original mapping concept and to develop an analogue database to the “manually” created, existing SOTER databases. A simplified soil parent material classification was developed and tested for remote sensing based application. Multitemporal, visible, near infrared and thermal channels were used to compile the RS dataset which was later complemented with SRTM data and terrain derivatives as well. The suggested method can produce the first level delineations of the major PM units which can be further subdivided into smaller and more specific units as more data become available. The detail produced for the unconsolidated PM part of the pilot area is quite promising it shows all the major soil and landscape units that are important for soil mapping at the targeted - 1:1M -scale of SOTER. The consolidated part has much less detail, those areas still need legacy data for more detailed PM unit delineation. That procedure can be used anywhere in the world, where PM data are limited.