Soil Surveys in Brazil and Perspectives in Soil Digital Mapping

Abstract

In analyzing the evolution of pedologic mapping perspectives in Brazil, it is noteworthy that they are based firmly on geology and focused on soil aptitude for agricultural use. Mapping detail was improved between the decades of 1950 and 1980. The mapping initially concentrated in the Northeast and Southeast regions, shifting its orientation in recent decades with the opening of the Brazilian agricultural frontiers. Remote sensing, geographical information systems, and informatics allowed increased map detail and promoted technological changes in map production. This revolution provided the development of digital soil mapping (DSM) as a set of methods and techniques to automate the soil surveys in Brazil. Despite the technological advances, only 1% of the Brazilian territory has soil maps on the scale of 1:25,000. In 1990 for economical, technological, and methodological reasons there was a decrease in both surveying and detailing processes. In a response to this reality Brazil has used new software and technologies, as well as the accumulated knowledge, to increase technological development of soil surveys. The integration of existing techniques and data favor the faster construction of more detailed and more interactive soil maps for a larger parcel of the country. This perspective, as the former one, will require some modifications to the soil mapping both in the methodology and also in the approach.

Synergy between digital soil mapping and crop modeling: influence of soil data on sugarcane attainable yield

“…According to the results presented in this study, the ML algorithm was fairly capable of capturing soil variability. Our results reinforce the potential of DSM to map soil attributes in medium to large areas, especially in countries such as Brazil, where soil data is scarce and imposes a challenge to soil mapping processes (Nolasco de Carvalho et al, 2015).…”

Fine-scale soil mapping with Earth Observation data: a multiple geographic level comparison

“…Digital soil mapping (DSM) has been explored in Brazil to produce updated and higher resolution maps of soil properties and soil taxonomic classes (Chagas et al, 2010;ten Caten et al, 2012;Samuel-Rosa et al, 2013;Giasson et al, 2015;Arruda et al, 2016;Vasques et al, 2016;Moura-Bueno et al, 2019). Different methods were also adapted for predicting soil taxonomical classes (Nolasco de Carvalho et al, 2015;Coelho et al, 2021), such as the probability mapping (Giasson et al, 2006), categorical mapping (Bazaglia Filho et al, 2013;Wolski et al, 2017;Moura-Bueno et al, 2019), Boolean logic (Rizzo et al, 2020), spatial disaggregation (Sarmento et al, 2017), among others. The DSM relies on the relationship of soil observations with environmental data employed in a model, which delivers a predicted value for a specific location usually coupled with an uncertainty estimate (McBratney et al, 2003;Lagacherie et al, 2006;Minasny and McBratney, 2016).…”

Geomorphometric segmentation of complex slope elements for detailed digital soil mapping in southeast Brazil

“…There are only exploratory or reconnaissance soil maps covering most of the Brazilian territory and soil types corresponding to the soil series concept are not yet established (Lepsch, 2013;Carvalho et al, 2015). Because of the available soil maps' coarse cartographic scale, they are not useful for farming and civil engineering management decisions at field or catchment scales (Sanchez et al, 2009).…”

“…Because of the available soil maps' coarse cartographic scale, they are not useful for farming and civil engineering management decisions at field or catchment scales (Sanchez et al, 2009). Only 0.25% of the Brazilian territory is covered by 1 st or 2 nd order soil maps (scale ≤1:35,000) (Carvalho et al, 2015;Mendonça-Santos and Santos, 2007). This coverage is much less than other countries of similar size, such as the USA, where the National Cooperative Soil Survey (NCSS) has mapped the soils of nearly every county at the These soil maps were produced from a combination of soil-landscape relationships based on the tacit knowledge of field experienced pedologists, with field observations and point measured soil properties (Hudson, 1992).…”