## 3 Results and Discussion
### Delimitation of Coastal Lakes
#### 3.4.4 Eutrophic Lakes  
Bodeira  
The Bodeira lake occupies an area of 1.7 ha (Figure 8), with only 6.2% of open water. The seasonal variation in Bodeira is more extreme than in the other lakes, as at the end of summer the lake basin is empty of water. The aquatic vegetation and the _Phragmites australis_ occupy 20.7 and 28.8% of the area, respectively. The increase in the alluvial forest mentioned in other lakes was also observed in Bodeira, where this habitat occupied 44.4% of the area considered and has undergone a large increase in the last few decades. The recovery of alluvial forest with _Alnus glutinosa_ is the most relevant characteristic of this lake. In the Bodeira area, this type of cover has increased from 0.18 ha (in 1989) to 0.77 ha (in 2017). Outside the lake area, this habitat has increased from 0.53 ha to 6.47 ha of continuous forest.  
In the PDRN, the Bodeira lake simultaneously appears as a coastal lagoon and a natural eutrophic lake (Figure 9), even though these habitats are not compatible. Based on the results of water and sediment analysis, this lake should be designated as habitat 3150 (Table 2), which coincides with the information in Ramsar Fact Sheets, in which this lake is defined as a small freshwater coastal lake. As in Xuno, there are also small areas with other main habitats, such as alluvial forest (0.38 ha) and pseudo-steppes (0.09 ha). This adds to the problem of the simultaneous definition as a coastal lagoon and natural eutrophic lake.  
Both lakes show important similarities (regarding the water and sedimentary composition) to freshwater lakes separated from the sea (see Section 3.3). The high contents of nutrients (N and P) also indicated that the lakes are eutrophic and justify inclusion of the lakes in habitat 3150 [15]. The inclusion in a same zone of coastal lagoons and a natural eutrophic lake (Table 3 and Figure 9) is clearly an error. The characteristics of each habitat in the same water mass and their physiochemical  
Figure 7: Lake of Xüno. (**a,b**) represent the temporal evolution of environmental units in 1989 and 2017, respectively. (**c**) shows TRI classification, in black, values below mean and in white the values above mean. (**d**) Official cartography representing the distribution of habitats from Annex I of Habitats Directive. The red line in all cases represent the extent marked for the lagoon by our analysis (IGN, [20]; Xunta de Galicia ©).  
parameters cannot be very different, as shown in Table 2. Coastal lagoon occupied a major part of these lakes (Figure 9), and although it is the main habitat, this space cannot be considered a linked natural eutrophic lake.  
In relation to the habitat division, particularly in relation to the categorization of eutrophic lakes by PDRN (Figures 7 and 8), in the present study it was considered that the lake basin corresponds to a unique habitat and that division in units with a limited spatial representation does not correspond to the functionality of wetlands. Indeed, this division appears to have arisen as the result of erroneous land  
Figure 8: Lake of Bodeira. (**a,b**) represent the temporal evolution of environmental units in 1989 and 2017, respectively. (**c**) shows TRI classification, in black, values below mean and in white the values above mean. (**d**) Official cartography representing the distribution of habitats from Annex I of Habitats Directive. The red line in all cases represent the extent marked for the lagoon by our analysis (IGN, [20]; Xunta de Galicia ©).  
Figure 9: (**a**) represent lake of Xuño and (**b**) represent lake of Bodeira. In both cases it shows the surface occupied by coastal lagoon habitat (blue), and natural eutrophic lake habitat (brown). The red line in all cases represent the extent marked for the lagoon by our analysis (IGN [20]; Xunta de Galicia ©).