ABSTRACT
This paper concerns the monitoring of the marine and coastal environment in South Wales using state-of-the-art survey techniques and a geographic information system (GIS). One of the most important natural resources in South Wales is its marine aggregate. This resource is vital to the regional economy in that it provides the building industry with that most essential of raw materials, sand and gravel. However there are growing concerns as to the possible effects of the commercial extraction of aggregate on the coastal and marine environment, and a number of environmental monitoring procedures are in place to detect changes. These range from traditional beach profile surveys to state-of-the-art airborne remote sensing techniques. The National Assembly for Wales has pioneered the use of airborne LiDAR (Light Detection and Ranging) for the acquisition of highly detailed topographical data on beaches, and CASI (Compact Airborne Spectrographic Imager), for the determination of the state of the vegetation along part of the coastline. LiDAR is capable of accurately detecting changes in beach levels. The procedure began in 1998 and will continue until at least 2003, giving an unprecedented insight into coastal changes over time. Another remote sensing technique has also been deployed. Close-range photogrammetry has been used to determine the degree of retreat of unstable seacliffs. All the data collected is used to populate a GIS. Data acquired in this way is compared with that from various monitoring procedures carried out previously (aerial photography and beach profiles). A number of advanced techniques have been developed in parallel to the GIS for the interpretation, analysis and visualization of the data. A number of invaluable lessons have been learned. Apart from the site-specific monitoring procedures, other strategic data sets such as the macro-fauna community distribution, modelled parameters, etc., have also been acquired from a number of sources. Amongst these parameters, the most important of all is the sediment environment. It defines the fuzzy geographical boundaries in which distinctive hydrodynamic regimes operate. A summary on the resources and constraints is generated for each of the sediment environments. These resources and constraints summaries together with the GIS form the basis of a decision-support system for assisting the formation of policy for the management
of the marine resource. The findings will shape future decisions about the sustainable use of the marine resource in South Wales.
