## 2 Materials and Methods  
The six crops chosen for this work were wheat, barley, oat, lupin, triticale, and broad bean, considered very representative of the agricultural landscape of the Alentejo region. The first part of the methodological approach for this work is shown in the diagrammatic scheme of Figure 1, corresponding to the processes used for suitable area extraction and field validation. In the first stage of Figure 1, a geospatial data setup was carried out. The values of the physical and chemical soil properties, which were texture, cationic exchange capacity, pH, and organic carbon, assigned to typify and discriminate the adequacy of soils for these crops, are shown in Table 1. These values resulted from field trials in these species carried out in the Plant Breeding Station Unit in Elvas, Alentejo. Lupin and broad bean soil occupations were considered interchangeable with oat and triticale, due to the similarity of their soil requirements. Physiographic classes of slope and elevation were also considered for the modeling, with respective values lower than 5% and 300 m being a restrictive condition for establishing potential crop areas. An additional condition was that only patches larger than 2 ha were considered for analysis. In this context, the spatial datasets used in the first stage were as follows: (i) The Infosolo Legacy Database [43], representative of data from 3461 soil profiles established between 1966 and 2014, with data on soil pH, organic carbon content, textural composition for soil taxonomy, and cation exchange capacity. These data are mapped in Figure 2; (ii) ESA's EU-DEM v1.1 Digital Elevation Model with a spatial resolution of 25 m [44] for the inclusion of slope and elevation constraints; and (iii) the Portuguese official land use/land \begin{table}
\begin{tabular}{c c c c c} \hline
**Soil Properties** & **Oat/Lupin** & **Triticale/Broad Bean** & **Barley** & **Wheat** \\ \hline Texture & LSa, SaL 1 & LSa, SaCL 1 & SaL, SaCL 1 & SaL, SaCL 1 & SaL, SaCL 1 \\ CEC & 14 to 20 & 14 to 20 & 14 to 20 & 14 to 20 & 20 to 26.7 \\ pH & 6.3 to 7.1 & 6.3 to 7.1 & 7.1 to 8 & 7.1 to 8 \\ Organic carbon (\%) & 0.1 to 1.3 & 1.3 to 4.4 & 1.3 to 4.4 & 1.3 to 4.4 \\ \hline \end{tabular} \({}^{\dagger}\) Textures: LSa—loamy sand; SaL—sandy Ioam; SaCL—sandy-clay-loam.  
\end{table} 
Table 1: Assignment of soil chemical and textural composition for four cereals and two legume crops. Figure 1: Schematic diagram of the methods used for suitable area modeling and mapping for the chosen cereal/legume crops and field validation. cover map for 2018 [45], a thematic polygon map based on photointerpretation and with a hierarchical 5-level nomenclature with more than 80 classes. All this geospatial information was gathered and combined with a geographic information system, ArcGIS Pro 3.1. The second stage involved the processing of the geospatial data to obtain suitability maps for the considered cereal/legume crops, using the same GIS software. Map overlaying enabled the identification of four main geographical areas more representative of the distribution of each of the chosen cereal and/or legume crops. In the third stage, the estimated areas were subjected to a validation scheme analysis of land use in 199 field points sampled within the locations obtained in the second stage. The mentioned minimum area restriction for patch areas, 2 ha, was used. The sampled points fell into the area delimitated by WGS84 geographic coordinates 37.594\({}^{\circ}\) N and 38.418\({}^{\circ}\) N of latitude and 7.390\({}^{\circ}\) W and 8.213\({}^{\circ}\) W.  
Figure 3 corresponds to the subsequent process of evaluating the mass/energy balances of the chosen crops in the selected areas. It shows the modeling processes used to estimate mass and energy balances of the chosen cereal/legume crops in the main representative estimated geographical areas, considering each of the 16 combinations of four crops and four main selected geographical areas mentioned below.