Soils properties define fertility and influence water movement

     A base soil map that identifies at least the soil types by names, and preferably for soil attributes, for 3 soil layers, is needed for the starting point of deriving the soil attributes for hydrologic parameters.  That is, a soil map and a series of soil parameters are required (soil depth, # soil types, # soil layers, soil description).   

Espirito Santo State and Minas Gerais

     The soil data in GEOBASE is only for the state, whereas coverage for the entire region is needed. Several data sources were evaluated, all derived from the original RADAM surveys. As the best-documented source, the EMBRAPA product “O Novo Mapa de Solos do Brasil Legenda Atualizada , Documentos 130, escala 1:5.000.000, ISSN 1517-2627 Dezembro, 2011” was chosen. It contains a total of 18 soil types. Soil % obtained from RADAMBrasil, various other parameters obtained from USDA. The soil map for the VIC  basins was derived from this EMBRAPA 1:5.000.000 map.

                                          Solos_Brasil 1:5M data sources (left), processed into VIC domain (right)

     The soil file provides, for each grid cell, data on the soil texture (sand and clay content) of each soil layer. For this application, default from the World Inventory of Soil Emission Potentials (WISE) pedon database, using the SOILPROGRAM, with assumptions made about depth of soil layers. Then the Soil parameter file  specifies, for each grid cell, the value for a series of  soil parameters. Most of these parameters are derived from the above soil file data on texture, using the generic methods.

Bacias Rio Jucu and Rio Santa Maria da Vitória

     For DSHVM, the 1:1M soil map was provided by Leandro Feitoza (INCAPER).  The original RADAM at 1:250.000 was digitized, however it was released at 1:400,00, for use in GEOBASE, for an eventual release at 1:1M.  The description of the soils, and the soil groupings, is provided in:  SEAMA; UFV. Fisionomia e Solos Capixabas. In: SEAMA; UFV. ATLAS de ecossistemas do Espírito Santo. Vitória, ES : SEAMA : Viçosa; MG : UFV, 2008. Il. color. pp 50 – 61

              Solos_Brasil/GEOBASES 1:1M data sources (left), processed into DHSVM for Jucu and SMV (right)