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2.1.4 Maps of the site

A series of biogeographic maps exist for the area covered by the Cardigan Bay cSAC. Map types and potential sources are given below or in Appendix 2.

Figure 7.    Indicative bathymetry of Cardigan Bay cSAC from recent acoustic surveys.

Figure 7.    Indicative bathymetry of Cardigan Bay cSAC from recent acoustic surveys.

Figure 8.  Indicative distribution of seabed substrates and community types within Cardigan Bay cSAC.

Figure 8.  Indicative distribution of seabed substrates and community types within Cardigan Bay cSAC.

2.1.4.1        Navigation, bathymetry, sea bed substrates and tidal strengths

Marine charts provide a variety of information, from bathymetry [10] to seabed substrata and obstructions. Several different types of marine charts cover Cardigan Bay. A list of relevant ones available from by the Hydrographic Office is given in Appendix 2.

Recent broad scale acoustic discrimination system surveys of Cardigan Bay have provided information for the development of bathymetric maps and the distribution of seabed substrates. These are held on GIS [11]. Examples of these are given in Figure 7. and Figure 8.

2.1.4.2        Geology & Geomorphology

The British Geological Survey provide a series of charts of bedrock, quaternary and seabed sediments for Cardigan Bay. A list of relevant charts is given in Appendix 2.

2.1.4.3        Coastline

The Ordnance Survey provide a series of maps at a variety of scales covering the coastline and land mass adjacent to Cardigan Bay. The most commonly used scales are:

Ordnance Survey 1:50,000 scale Land Ranger Series maps, colour

Ordnance Survey 1:25,000 scale Path Finder/Outdoor Leisure Series maps, colour

Ordnance Survey 1:10,000 scale maps, black and white

Ordnance Survey 1:2,500 Landline maps

2.1.4.4        Marine Communities

Sublittoral

Broadscale maps (and descriptions) of Cardigan Bay’s underwater marine communities are shown in the Marine Nature Conservation Review area summary [12] and Great Britain overview of benthic marine ecosystems [13]. Recent broad scale acoustic discrimination system surveys of Cardigan Bay have developed maps of the distribution of seabed communities. These are held on GIS. An example is given in Figure 7.

Intertidal zone

A large proportion of the Welsh coast has been surveyed and mapped by the Countryside Council for Wales Phase 1 Intertidal Survey, and the intertidal area adjacent to the cSAC boundary is included within the area surveyed. This ongoing survey has resulted in the production of marine biotope [14] maps of the intertidal. These are held on GIS. An example showing New Quay bay is given in Figure 9.

Figure 9. Intertidal communities around New Quay. From the CCW phase one intertidal survey.

Figure 9.         Intertidal communities around New Quay. From the CCW phase one intertidal survey.

Reproduced with the permission of the controller of HMSO © crown copyright.

[10] Bathymetry: Depth of water below the level of lowest astronomical tide.

[11] Geographical Information System

[12] Brazier, D,P., Holt, R.H.TF., Murray, E., & Nichols, D.M. 1999. Marine Nature Conservation Review Sector 10. Cardigan Bay and North Wales: area summaries. Peterborough, Joint Nature Conservation Committee. (Coasts and seas of the United Kingdom. MNCR series).

[13] Hiscock, K., ed. 1998. Marine Nature Conservation Review. Benthic marine ecosystems of Great Britain and the north-east Atlantic. Peterborough, Joint Nature Conservation Committee. (Coasts and seas of the United Kingdom. MNCR series).

[14] Biotope: The habitat (i.e. the environment’s physical and chemical characteristics) together with its recurring associated community of species, operating together at a particular scale.