## 10 Conclusions  
A fully automated shallow habitat classification approach was proposed, making use of multi-source, high-resolution swath sonars, for improved seafloor classifications in a total area of 84 km\({}^{2}\). We exploit the efficacy of the combined use of MBES and SSS for gaining more acoustic backscatter spectral bands in a single survey, as well as dense bathymetric and angular backscatter responses information. Integration of MBES and SSS is an operationally efficient practice, quite common in marine geophysical surveys, to gain maximum information from a single survey. Such a multi-platform approach can offer at least three acoustic backscatter spectral bands on a single survey with varyingdata resolutions and mapping scales, supplemented by bathymetry and angular backscatter response information. Combination of the above systems proved to offer a good trade-off between survey effort and information gain, mainly in shallow waters. The poor textural content and coverage in shallow waters of the MBES was supplemented by the higher equivalents of SSS, offering an improved classification of the bottom classes. As a rule, MBES although providing poorer coverage in shallow waters, it provided the best single-system seafloor classification accuracies, but it needed to be combined with an object-oriented analysis made available through the full coverage SSS mosaic. On the other end, individual frequency backscatter mosaics, no matter which system they were derived from, were unable to provide adequate habitat discrimination. This was much improved when all backscatter frequencies were used in synergy, but it was still below the accuracy levels achieved with the fully integrated data model, combining both SSS and MBES data derivatives. NMPZ, as an MPA of high local importance, being the first no-take zone in Greece, stood as a perfect case study to showcase the above findings. It is a shallow, high diversity MPA, hosting extensive fields of the protected phanerogams _P. oceanica_ and _C. nodosa_ that have been fully and in detail mapped, offering the background for local management stakeholders to set the standards for an optimized marine spatial planning of the area.  
Conceptualization, E.F., P.B. and G.P.; Data curation, D.C., X.D., N.G. and Y.R.; Funding acquisition, G.P., C.D., M.G. and G.F.; Investigation, E.F., G.P., D.C., X.D., N.G. and M.G.; Methodology, E.F. and P.B.; Project administration, C.D.; Resources, C.D.; Software, E.F., D.C. and Y.R.; Supervision, P.B., G.P., M.G. and G.F.; Validation, E.F.; Visualization, N.G. and S.K.; Writing--original draft, E.F.; Writing--review & editing, P.B., G.P., X.D., S.K., C.D. and Y.R.  
This research was funded by the European Regional Development Fund (ERDF) and National resources (Operational Programme 'Environment and Sustainable Development' under the NSRF 2007-2013).  
This study was majorly supported by the Management Agency of the National Marine Park of Zakynthos in the framework of the project 'Monitoring of coastal and marine habitat types of EU community interest' funded by the European Regional Development Fund (ERDF) and National resources (Operational Programme 'Environment and Sustainable Development' under the NSRF 2007-2013). The authors would like to thank the crew of the R/V _Socrates_ for significantly contributing in the field work, as well as the anonymous reviewers for constructively commenting on the manuscript.  
The authors declare no conflict of interest.