Spatial multi-criteria analysis, trophic networks and marine ecosystem management: the case study of the SAC Tegnùe di Chioggia

Proper management of marine environments often requires a compromise between conservation and the sustainable use of local resources. This is the result of the recent scientific study "Spatial multi-criteria analysis based on food web model results: application to a marine conservation area", carried out by a group of Italian scientists including Elisa Donati, a researcher at OGS.

The project focused on the Special Area of Conservation (SAC) “Tegnùe di Chioggia”, which is recognised as an area of high ecological interest under the EU Habitats Directive due to the presence of significant biogenic rocky outcrops. Despite this recognition, the site still lacks a formal management plan to ensure fair and sustainable environmental management.

To fill this gap, the research team used models of marine trophic networks to simulate the effectiveness and environmental impacts of several direct and indirect management strategies proposed for the SAC “Tegnùe di Chioggia”.

Therefore, a spatial multi-criteria analysis was performed to take into account several ecosystem parameters and combine them into a comprehensive and easy-to-interpret indicator. This integration into a single score facilitates and streamlines ecosystem management decision making and strategic environmental assessment procedures.

Three different management approaches were simulated: the spatial extension of the existing SAC, the introduction of winter artisanal fishing in the area, and a combination of both these strategies.

The results showed that none of the three hypothetical scenarios would disrupt the balance between species or the functioning of the local ecosystem. However, while the expansion of the SAC would lead to an increase in total biomass and commercial fish biomass, the imposition of new restrictions on fishing fleets would undermine social and economic tolerance for the expansion of the protected area. On the other hand, the introduction of artisanal fishing would have minimal impact on food webs. Finally, the combination of both strategies would partially reduce the benefits associated with the expansion of the protected area.

In conclusion, the study has made it possible to analyse and classify all three strategies, using the single indicator developed for each one of them. Besides providing a useful framework to support sustainable management of the SAC “Tegnùe di Chioggia”, the research demonstrates that spatial multi-criteria analysis based on trophic network indices could also be used for other marine protected areas. In this regard, the research team emphasised the importance of proactive stakeholder involvement as a key factor in the implementation of truly functional and collaborative environmental management strategies.