Identify what dysfunction in the natural system is implied in relation to the Policy Issue.

Subtask Description:
Identify what dysfunction in the natural system is implied in relation to the Policy Issue.

Action points of the implementation:

Mar Piccolo, Taranto, Italy

Policy Issue:
Sustainable use of the Mar Piccolo resources in order to include mussel culture.

Human Activities:
Urban and industrial activity, mussel culture, urbanization, shipping, maritime transport.

General Information:
The area is a field of many conflicting activities but also has always been one of the most important mussels farming areas in the country. In particular, fishing, distribution, catering, tourism, transport, import and export are activities directly connected to aquaculture, bringing an economic improvement and therefore a greater social welfare. However externalities, such as social problems or illegal aquaculture plants that over-exploit the existing natural resources, are causing damage to the ecosystem. During the last years, data from the local market evidenced quantity and quality reduction of the harvested mussels. The major stakeholder concerns are connected to the sustainable development and welfare of the activity.

Example of Implementation:
In Mar Piccolo, the Study Site team, after agreeing on the Policy Issue with their stakeholders, constructed the following table, in order to identify more efficiently the ecological dysfunctions imposed to the system from the Human Activities that are related to the coastal zone and the policy issue. Furthermore, they identified the important variables in order to link these human activities to the impacts in the ecosystem and, going one step further they identified the impacts in the ecosystem’s goods and services.

Table 1 : List of the main Human Activities, Dysfunctions and Impacts for Mar Piccolo in Taranto.

Human Activities

Ecological dysfunction

Key variables linking forcing to impact

Impacts on ecosystems goods and services

Mussel culture


Reduction of the mussel productivity and health


Mussel recruitment, employment, local jobs

Reduction of the local market, loss of jobs


Eutrophication effects


Anoxia, benthic habitat, diversity loss, toxic and harmful algal blooms


Change of trophic structure

Heavy industry

Biochemical pollution

Heavy metals, PAHs PCBs


Contaminated mussels, stress on organisms



Eutrophication and toxic substances


Fertilizer use, field drainage, crops, pesticide use, surface water transport


Change of trophic structure, ground-water contamination, ammonia emissions

Navy docks, large ship traffic

Physical habitat destruction

Shoreline development, resuspension from large ship traffic


Reduction of mussels recruitment, perceived, environmental quality



Diversity loss and invasive species

Bacteria, phytoplankton and zooplankton, phytobenthos and zoobenthos, nekton

Perceived environmental quality, water transparency

This approach provides transparency through the cause and effect chain of every important human activity in the area. The column of the “impacts on ecosystem goods and services” provides also an insight to the probable interconnections between the ecological, economic and social systems.

Carmela Caroppo,