Inside and outside the boundaries: contribution of the valli da pesca to the Venice lagoon Ecosystem Services

The Venice lagoon is a social-ecological system, result of centuries of co-evolution between natural and anthropogenic drivers. All this produced a complex interacting set of different habitats and parts, including some confined, man-managed areas known as valli da pesca. These areas, similar to ‘miniature lagoons’, have progressively been separated in a permanent way from the lagoon itself, depending almost completely on human intervention for functioning and maintenance. Due to both the “artificial” origin and difficulties of accessing, these portions of the lagoon have previously been excluded from analyses, surveys, monitoring programs. The present work constitutes the first attempt of a spatially explicit Ecosystem Services (ESs) assessment of the entire lagoon, included the valli da pesca, both in terms of capacity and flow. Obtained results showed that these areas, despite they represent just the 18% of the total lagoon area, play an important ecological role, contributing for 35% of the ESs capacity and 27% of the flow in comparison with the whole lagoon. Furthermore, the valli da pesca showed that different management strategies, aimed to maximize just a single ES, like aquaculture or hunting (or both), could have significant contrasting effects on the landscape features.