## 3 Results and Discussion
### Microbiota and Wood Decay  
For both _16_S and _ITS2_ sequences, it was observed that the communities of the samples treated according to the two extraction protocols were very similar, as it can be clearly observed in Figures 3 and 5. This suggests that the obtained results can be considered as representative of the actual communities present in the wood. The differences in the relative frequency registered for almost all identified taxa could be attributed to the extraction method or to the anisotropic distribution of the microorganisms inside the wood.  
On the contrary, the neat differences observed in the composition of microbial communities in Naples and Pisa samples should be attributed to the lying site. In fact, it is well know that the heterogeneous environmental conditions of the soil (e.g., pH, climate, organic carbon availability) influence the microbial community [146; 147], and soil represents the main source of colonizers for wood in ground contact [148; 149]. This statement is obviously valid also for WAW that lies at a certain depth included in waterlogged soil for centuries and that, during excavation and recovery, comes into contact with the most superficial ground layers, the richest in term of microbial biomass and diversity.  
By analyzing more in depth the differences among the bacterial communities of the two sites, it is evident that Naples samples were characterized by the highest number of potential biodeteriogenbacterial genera (_Pseudomonas, Janthinobacterium, Flavobacterium, Sphingomonas, Methylovigula, Bryobacter, Acidithiobacillus, Thiomas_, and _Rhodanobacter_) whereas only three of these taxa, _Pseudomonas, Methylovigula_, and _Bryobacter_ were present in Pisa woods. Regarding the fungal communities, 10 of the 13 potential biodeteriogen taxa identified were present only in Naples samples (_Pleurotheciella, Cadophora, Podospora, Acidomelania, Cerinosterus, Reticulascus, Mollisia, Lecytrophophora, Penicillium,_ and _Exophilata_) while three were exclusive of Pisa (_Angulomyces argentinensis, Schizophrenia commune, Cladophilophora_). In this case, it worth remembering that lot of the sequences extracted from Pisa samples remained unidentified so the presence of other ligninolytic and/or cellulolytic species cannot be excluded.  
Table 4 reports the results of the physical analyses carried out to evaluate the level of degradation of Pisa woods in 2008 and 2018. Data clearly show a general increase in the degradation of wood. For holm oak and oak, an increase by 100\(-\)200% of MWC and by 4% of LWS values was registered while for elm and ash MWC almost doubled and LWS increased by ca 5\(-\)10%. Degradation occurring during the 10 years of storage could be attributed to the ongoing activity of biodeteriogens present inside the wood, particularly to the fungi (mostly basidiomycetes) which are better competitors with respect to bacteria. It is worth underlining that basidiomycetes proved to have a high degradative potential even in condition of complete imbibition, usually considered as protective for WAW against these biodeteriogens.  
Finally, it is interesting to note that the bacterial genus _Methylovigula_ was present only in sample PF. As discussed, these bacteria are obligated to use methanol as carbon source. As this molecule is a degradation product of woody materials, it is probable that it was particularly concentrated in PF which was characterized by an advanced state of decay.