Constraint Mapping as a Means of Further Refining Saltmarsh Re-Creation Opportunities for the UK Solent Region

Abstract

Based on geomorphological criteria, the Coastal Habitat Management Plan (CHaMP) for the Solent identified some 4,800 hectares of land potentially suitable for the creation of intertidal habitat, principally saltmarsh, through the use of managed realignment. Using “constraint mapping,” this study set out to illustrate that limitations to habitat re-creation through inundation are not merely geomorphological in nature. Indeed, a broad range of social, political, legal, technical, and economic constraints exist and must be evaluated in conjunction with physical parameters if the objectives of the European Birds and Habitats Directives are to be met, and so that future coastal defense policies ensure maintenance of the “favorable conservation status” of designated sites. A numerical filter system has been used to re-evaluate individual sites to establish “realistic” opportunities for compensatory saltmarsh creation in the Solent. As a result of taking into account wider socioeconomic constraints, it is clear that fewer areas are available for habitat creation purposes than were initially identified in the Solent CHaMP study.

Keywords:

• constraint mapping
• managed realignment
• saltmarsh recreation
• Solent

Notes

^†No definitive explanation of what constituted “non-urban” land use was available.

Since submitting this article, English Nature (the UK Government's statutory agency responsible for nature conservation in England) has been reorganised into a larger body with broader responsibilities, entitled Natural England.