## 3 Results  
A total of 6,381,454 GEDI lidar pulses were acquired over Italy between 2019 and 2020 (Figure 2). Among these, 5,167,420 pulses were in forests. The number of GEDI pulses per region ranged between 51,429 in Aosta Valley to 640,206 in Tuscany, while the number of pulses per km\({}^{2}\) in the forested area ranged between 35.6 in Umbria to 84.4 in Calabria.  
48% or 3,017,244 of the GEDI pulses acquired in Italian forests were over areas covered by ALS data. We found a consistent relationship between the AGBD and the CHM groups, with an r\({}^{2}\) of 0.75, ranging between 0.87 in Calabria and 0.42 in Liguria (Figure 3).  
Figure 2: AGBD of GEDI pulses acquired over Italian forests. On the right is the percentage of GEDI coverage to the forest area by NUTS 2 unit.  
According to our automatic procedure (Section 2.4), 1,793,802 forest disturbances occurred in Italy between 1985 and 2019 (Figure 4). In terms of area, they covered approximately 3 million hectares, corresponding to 27% of the total Italian forest area. The average area of the predicted disturbance was 1.72 ha, while the median value was 0.83 ha. The years 1985, 2017, and 1990 were those with more forest disturbances, while the year 2014 was the less disturbed (Figure 5). At the NUTS 2 level, Tuscany was the most affected region, with 431,479.86 ha of forest disturbances during the study period. Overall, Tuscany, Calabria, Sardinia, Lazio, and Sicily host more than half (54%) of the total disturbed forest area. Using the forest harvestings reference dataset, estimates of omission errors ranged from 29% (in 2012) to 65% (in 2001), while commission errors were between 18% (2014) and 88% (2003).  
There were 1,080,483 GEDI pulses acquired over mapped forest disturbances. The number of pulses acquired yearly over forest disturbance ranged between 84,505 (for forest disturbances occurred in 2017) and 10,272 (for forest disturbances occurred in 2010). We found that the AGBD median values ranged between 48 t ha\({}^{-1}\)--on 3 YSLD--and 70 t ha\({}^{-1}\)--on 34 YSLD. Several oscillations in the AGBD values were recorded over time (Figure 6), but in general, AGBD in the reference forest harvestings (Figure 6A) increased more rapidly than in the predicted forest disturbance (Figure 6B), overtaking 80 t ha\({}^{-1}\) in 11 YSLD. These results are congruent with the data provided by [74]. In both reference harvestings and forest disturbance, the AGBD does not increase after 15 YSLD. The average of the AGDB between 13 and 17 YSLD was 94 t ha\({}^{-1}\) in harvested areas and 69 t ha\({}^{-1}\) considering all disturbances.  
Figure 7 shows AGBD values of GEDI footprints acquired over different kinds of forest disturbance and over undisturbed forest, suggesting relevant differences between undisturbed and disturbed forests, but also between the different kinds of disturbances.  
Figure 3: Left—scatter plot of aggregated AGBD and CHM with the blue line showing the linear correlation. Right—a map indicating the different correlations for each Italian region.  
Figure 4: Comparison between predicted forest disturbance and clearcuts in one of three cells (in red) of the reference dataset (left). Predicted forest disturbance map (top-right) and two focuses (bottom-right).  
Figure 5: Per year area of forest disturbance predicted in Italy. On the right, the overall disturbance area is shown per region.  
Figure 6: Median of AGBD values per YSLD in the reference dataset of forest harvesting (**A**) and all forest disturbances predicted across Italy (**B**). The black points show average values calculated using a moving window of 5 YSLD.  
Figure 7: Comparison of AGBD between GEDI pulses acquired in 2019 over different kinds of forest disturbances that occurred in 2019.