## 3 Results
### Spatiotemporal Dynamics of Macrophyte Communities  
Figure 2 shows seasonal maps representing the spatial distribution of macrophyte meadows from 2015 to 2020. Macrophyte spatial coverage (RM = S\({}_{\text{RM}}\) + D\({}_{\text{RM}}\)) ranges from a minimum of 29.9% (autumn 2016) to a maximum of 71.6% (summer 2017). A strong seasonal variation of the coverage of macrophytes with values increasing up to a peak in summer before declining in the autumn is clearly visible in both the maps (Figure 2) and bar chart (Figure 3a). The bottom cover classification (BS, \(S_{\text{RM}}\) + D\({}_{\text{RM}}\)), both in surface (km\({}^{2}\)) and percentage, is reported in Table 2 for all the years investigated. Focusing on the two density macrophytes subclasses (\(S_{\text{RM}}\) and D\({}_{\text{RM}}\)), the percentage of coverage of D\({}_{\text{RM}}\) is consistently lower than that of \(S_{\text{RM}}\), with the exception of some summer periods that are particularly favorable to the growth of this submerged vegetation (2015, 2017, and 2018). \(S_{\text{RM}}\) spatial coverage ranges from a minimum of 14.68% (spring 2018) to a maximum of 55.3% (summer 2019), while D\({}_{\text{RM}}\) ranges from 0.03% (autumn 2019) to 48.27% (summer 2018). As might be expected, in each year the highest percentage coverage of D\({}_{\text{RM}}\) was found in summer, during the peak of the growing season. The only exception is 2019, where \(S_{\text{RM}}\) almost completely replace D\({}_{\text{RM}}\) in all three seasonal maps (Figure 2). In contrast to summer 2019, the previous two years (2017 and 2018) are instead characterized by high spatial coverage of macrophytes, especially D\({}_{\text{RM}}\) (47.37% and 48.27% in summer 2017 and 2018, respectively). Figure 3: From top to bottom: (**a**) Time series of macrophytc cover (bare sediment = BS, sparse macrohypte = \(\mathrm{S_{RM}}\), dense macrohypte = \(\mathrm{D_{RM}}\)); (**b**) Bird groups (piscivores, herbivores, omnivores); (**c**) Chlorophyll-a (Chl–a); (**d**) Water level (m) in Lake Garda. The western portion of the Sirminoen Peninsula was more favorable to macrophyte growth, while the southern portion of the eastern sub-basin was mainly characterized by bare sediment (BS), resulting in a spatial difference between the two sub-basins (Figure 2). This is supported by transect analysis where the frequency of the two macrophyte sub-classes (\(\mathrm{SR}_{\mathrm{RM}}\) and \(\mathrm{D}_{\mathrm{RM}}\)) in the seasonal maps is higher in the western transects than in the eastern transects. Specifically, considering all ROIs and the entire study period (2015-2020), in the western transects the average frequency of the RM class is 74.71%, while in the eastern transects it is 50.20%. T1 is the most favorable transect for macrophyte growth (92.94%), while T5 and T6 are the most unfavorable (42.86% and 34.80%, respectively). The eastern side, especially areas that are shallower--closer to the shore and also towards the main shoreline to the southeast of the peninsula, where the slope is more gentle, tend to experience the largest areas of bare lake substrate over the time series (see bathymetry map in [PERSON] et al., 2014 [59]). In contrast, the western side is somewhat in the lee of the peninsula head and can be seen to consistently retain a greater proportion of macrophytes throughout the seasons compared to the eastern side. In addition, areas with more dense macrophytes are typically located in deeper water off the peninsula (Figure 2). In fact, in all transects, an increase in the frequency of the \(\mathrm{D}_{\mathrm{RM}}\) class can be detected in relation to distance from the coast. With the exception of T5 and T6, the \(\mathrm{D}_{\mathrm{RM}}\) class becomes dominant at the end of each transect (surpassing even the \(\mathrm{S}_{\mathrm{RM}}\) class).