Legend abbreviations are described bellow:

PBAC – Argissolo Bruno-Acinzentado

Moderately deep soils derived from sedimentary rocks, with abrupt textural change and low base saturation (Alisol);

PV

Deep soils derived from igneous rocks, with moderate textural gradient, and low base saturation (Argissolo Vermelho; Acrisol);

C-R

Low weathered soils (Cambissolo; Cambisol) and shallow soils with low to high base saturation (Neossolo Litólico/Regolítico Eutrófico/Distrófico; Eutric/Distric Leptosol/Regosol);

RL

Shallow soils with low to high base saturation (Neossolo Litólico Eutrófico/Distrófico; Eutric/Distric Leptosol);

SX

Moderately deep soils derived from sedimentary rocks, with abrupt textural change, low base saturation, and which are saturated with water for long periods of the year (Planossolo Háplico; Planosol);

RR

Shallow soils with low to high base saturation (Neossolo Regolítico; Regosol);

RL-RR

Shallow soils with low to high base saturation (Neossolo Litólico and Neossolo Regolítico; Leptosol and Regosol);

RY

Shallow soils of fluvial origin.

Both area-class soil maps were registered and geocoded with a grid of 5 meters cell size using the nearest neighbour resampling method. This method was used because it does not change data values.

Systematic positional errors \citep{Samuel-RosaEtAl2014} were corrected using affine transformation (R-package vec2dtransf \citep{Carrillo2012}).

Geologic maps

Both geologic maps were produced in the end of the 1980s. The difference between them is the quality of the cartographic database used. The less detailed geologic map was produced using topographic maps published by the Brazilian Army at a scale of 1: \citep{GasparettoEtAl1988} (Figure \ref{fig:geo-map-gasparetto}).