Plymouth Sound to Fowey

Summary

The study sought to explore ecosystem services assessments at the marine planning scale incorporating a combination of data rich and data poor areas, and to generate information that could help inform delivery of the Cornwall Maritime Strategy. As many ecosystem services as possible were to be considered, with a separate focus on cultural services.

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For additional information

Date: 2012-2015

The work presented here has been developed in six case studies of the VALMER Interreg 4A Channel project (2012-2015).

Coordination by M. Philippe, J. Ballé-Béganton and D. Bailly1
based on written contributions from N. Smith, P. Hoskin, W. Dodds, T. Hooper, L. Friedrich, N. Beaumont and C. Grifths

 

Site description

It is a large site, extending to 12 miles offshore. The area contains a recently designated Marine Conservation Zone and an offshore Special Area of Conservation. Fisheries, recreation and tourism are important economic activities, there is a commercial port at Fowey and the military makes extensive use of the area.

Focus of study

The study sought to explore ecosystem services assessments at the marine planning scale incorporating a combination of data rich and data poor areas, and to generate information that could help inform delivery of the Cornwall Maritime Strategy. As many ecosystem services as possible were to be considered, with a separate focus on cultural services.

The Plymouth Sound to Fowey site is not an existing management area, but was defined for the purposes of the VALMER project to be representative of a typical stretch of open coast with varied habitats (including rocky reefs, seagrass and kelp beds as well as sand and coarse sediments) and a range of issues and activities.

Key stakeholders and their involvement

The case study was co-ordinated by Cornwall Council, with the support of stakeholders through workshops to define scenarios and review results. The stakeholder group was deliberately constructed to only include those involved in environmental management, and participants included representatives of the harbour authority, statutory agencies, the National Trust and the Cornwall Wildlife Trust.

Approach for Ecosystem Services Assessment

The assessment of multiple services was refined to focus on nursery habitats for commercial species, carbon sequestration, sea defence and bioremediation of waste (considering supply of clean water, immobilisation of pollutants and nutrient cycling).

This component of the study took a spatial approach, mapping the delivery of the services based on information within the literature concerning linkage between habitats and services.

A primarily qualitative assessment was made of how services might change under management scenarios concerning dredge spoil disposal, converting protected areas to no-take zones and replace swing moorings with eco-buoys.

Some quantification and monetary valuation was undertaken for carbon sequestration. The assessment of cultural services used an online and face-to-face survey with local residents, containing a spatial component in which each respondent was asked to indicate three locations that were considered special, significant or valuable and three that were unpleasant, neglected or challenged.

Summary of main results

The baseline maps of ecosystem services delivery illustrated the importance of Plymouth Sound, with its varied habitats, as a nursery for a range of commercial species. The sand and coarse habitats that cover much of the site provided negligible levels of carbon sequestration relative to other habitats, although value of the site for carbon storage is nonetheless amounts to £1.4 million per year. These habitats play a greater role in nutrient cycling and the provision of clean water. The value of the increased carbon sequestration through the recovery of seagrass following the replacement of swing moorings is unlikely to offset the costs of installing the new eco-buoys.

Use of results

The stakeholders found the results useful for raising awareness, but options for their direct use are limited.

Examples of lessons learned

The wide focus of this assessment resulted in a necessarily cursory approach given limited resources, and the resulting outputs were less useful than stakeholders had hoped, suggesting that a narrow focus with a high level output would have been a better approach. However, qualitative outputs are a useful tool for stimulating discussion and considering trade-offs, even if they have limited direct use in policy development.

Fowey and Polruan

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