## 6 Data Collection Methods and Field Tests  
The proposed system has been tested in three different field operational tests performed in the framework of the EU FP7 Argomarine Project (FP7-SST-2008-RTD-1-234096) at different times, one in Zakynthos, Greece (hosted by the National Marine Park of Zakynthos), and two in Elba Island, Italy (hosted by National Park of Tuscany Archipelago). Selected sites are of great environmental relevance. Indeed, the National Marine Park of Zakynthos, established in 1999, is home to the endangered Loggerhead Sea Turtle (_Caretta caretta_), which is considered one of the oldest forms of life on the planet [32]. The National Park of Tuscany Archipelago is one of the areas with the highest oil spill densities according to the work [33] and is located in the Mediterranean Sea, between the Ligurian Sea and the Tyrrhenian Sea. The Archipelago is also included in the area of the Pelagos Sanctuary for Mediterranean Marine Mammals [34].  
Field tests were oriented to global assessment of the MIS platform and involved the acquisition and processing of data coming from heterogeneous sources including volunteers, as well as to the provision of decision support services. Tests included the acquisition of true data for verifying storage capabilities and near-real time functionalities. With a small amount of work for fixing interoperability issues, no problems were found for data integration. Stress tests using dummy data have also been performed for understanding the limits of the platform. On this basis, it can be judged that the system is adequate for managing regional data; in any case, the system might be scaled to an arbitrarily wide areas. Support for multiple areas is already included and operational. Besides true data, simulated data were also injected into the MIS to produce artificial perturbations and thus creating interesting anomalies to be managed by the implemented proactive services. The methods for real-time risk assessment were run automatically at regular time intervals to produce risk maps. The maps were visualized by experienced users belonging either to the Italian National Coast Guard and to the two marine parks (an example of the appearance of the map at the coarse scale is given in Figure 5). By visual inspection, the users found the map to convey meaningful and significant information and regarded it as a useful tool to better focus the attention on the areas that deserve a more accurate monitoring. The proactive services were asked to poll data from the databases including the computed risk maps. On the basis of polled data and of the logic used by the services, alert notifications were issued. A group of volunteers (also enrolled from the Pisa Naval League) has been asked to report a simulated oil spill either by using the WhiteBox device or the ARGO Sentinel app on their GNSS-equipped smartphones. The computed risk map changed consistently after receiving the volunteer reports. In particular, thanks to the inner logic of the agent in charge, such an event triggers a list of actions, including the updating of the risk map and the issuing of a notification to the authorities in charge of the area by SMS and emails.