## 2 Materials and Methods
### Photogrammetric Processing  
The images were processed using the PIX4 Dmapper software version 4.9.0 (Pix4D S.A, Prilly, Switzerland). The hardware has the following specifications: CPU: Intel(R) Core (TM) i7-4770 @ 3.40 GHz, RAM: 16 GB, GPU: NVIDIA GeForce GTX 1650, operating system Windows 10 Pro, 64-bit. The images corresponding to each scenario were processed in a single project configured as follows in Figure 3:  
**SCENARIO _A_:** This comprised forward strips (\(h_{f}\)) at a height of 120 m, using corridor flight, used in most flight application software (Figure 3A);  
**SCENARIO _B_:** This comprised forward strips combined with oblique perimeter images in each block (Figure 3B);  
**SCENARIO _C_:** This comprised forward strips combined with cross strips on the edges of each block at the height of 110 m (\(h_{c}\), cross-flight height) (Figure 3C), as proposed by the authors of [58; 59];  
**SCENARIO _D_:** This comprised forward strips combined with oblique perimeter images and a cross strip on the edges of each block -- Scenarios B + C (Figure 3D). The parameters used in the adjustment were similar to those used in [60; 61]; \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Block** & **Strip Type** & **Area (km\({}^{2}\))** & **Forward** & **Lateral** & **Flight Height (m)** & **GSD** & **No of** \\  & & **(km\({}^{2}\))** & **Overlap** & **Overlap** & **(m)** & **(cm/pix)** & **Images** \\ \hline Block 1 & Forward strips & 0.19 & 80\% & 60\% & \(h_{f}=120\) & 2.6 & 191 \\ Block 1 & Cross strip 1 & 0.019 & 80\% & 60\% & \(h_{c}=110\) & 2.4 & 19 \\ Block 1 & Perimeter 3D & & 80\% & 60\% & \(h_{f}=120\) & 2.6 & 74 \\ Blocks 1 and 2 & Cross strip 2 & 0.019 & 80\% & 60\% & \(h_{c}=110\) & 2.4 & 19 \\ Block 2 & Forward strips & 0.19 & 80\% & 60\% & \(h_{f}=120\) & 2.6 & 179 \\ Blocks 2 and 3 & Cross strip 3 & 0.019 & 80\% & 60\% & \(h_{c}=110\) & 2.4 & 19 \\ Block 2 & Perimeter 3D & & 80\% & 60\% & \(h_{f}=120\) & 2.6 & 69 \\ Block 3 & Forward strips & 0.23 & 80\% & 60\% & \(h_{f}=120\) & 2.6 & 215 \\ Blocks 3 and 4 & Cross strip 4 & 0.019 & 80\% & 60\% & \(h_{c}=110\) & 2.4 & 19 \\ Block 3 & Perimeter 3D & & 80\% & 60\% & \(h_{f}=120\) & 2.6 & 78 \\ Block 4 & Forward strips & 0.19 & 80\% & 60\% & \(h_{f}=120\) & 2.6 & 177 \\ Block 4 & Cross strip 5 & 0.019 & 80\% & 60\% & \(h_{c}=110\) & 2.4 & 19 \\ Block 4 & Perimeter 3D & & 80\% & 60\% & \(h_{f}=120\) & 2.6 & 68 \\ \hline Total & & 0.8 & & & & 1106 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Area in hectares for each block studied. \(h_{f}\) refers to the forward flight height, and \(h_{c}\) refers to the cross-flight height. * Key image scale: this was adjusted in total (as recommended in [31] because it establishes the full-scale image and gives better results), making it possible to define the size of the image where the key points were extracted in the initial comparison with the images [62];
* Matching image pairs: the aerial grid or corridor optimised the coincidence of pairs for the flight paths on the aerial grid;
* Targeted number key points: these were automatic, allowing the automatic selection of the key points to be extracted;
* Calibration: to evaluate the influence of rolling shutter compensation, calibration was performed both with the compensation enabled and using the \"Fast readout\" mode, which does not apply it;
* Rematch: this was automatic, allowing more coincidences to be added and improving the reconstruction quality [31]. Camera outer orientation was performed after the internal orientation in order to calculate the coordinates and determine the position of the cameras concerning the reference system of terrestrial coordinates [34]. This process was carried out through indirect georeferencing using GCPs. The GCPs were used to improve the orientation of the images and to transform the coordinates of the block into absolute coordinates. The CPs were used to assess the geometric accuracy.