Appendix
- Characterisation of the biotope
A thorough baseline survey should be carried out particularly where existing
information is scarce. In intertidal areas ACE studies will be useful in characterising
the biotopes particularly in large areas where time and cost considerations may preclude a
full quantitative survey. However localised core samples should also be taken at
representative sites usually on transects down the shore to give a more detailed
representation of the community and allow statistical analysis of the areas SACs and
determine levels of change. Bird surveys (WeBS counts) may also be necessary in some
areas. Subtidally grab samples in the habitats defined by acoustic survey or by reference
to bathymetric charts. Towed or remote operated video and epibenthic tows may also be
employed where appropriate.
The high costs and labour intensive nature of remote sampling (and video work) should
be taken into account and the number of samples and replicates taken will reflect this.
Information from existing data, remote sensing, acoustic surveys, bathymetric charts will
be useful to determine the location of monitoring sites and a stratified random sampling
strategy for quantitative sampling of the fauna will usually be employed on the basis of
this information. It may be necessary to store some samples to reduce laboratory analysis
which can be examined at a later date if necessary. A full account of survey design for
remote sampling is given in Hiscock (1998a), Baker & Wolff (1987), Holmes &
McIntyre (1984) and Rees et al (1990).
It is recommended that sediment samples should be taken at all sites for particle size
analysis, other parameters such as organic content, redox potential etc is also
recommended and in specific cases other information such as measurements of hydrocarbons,
trace metals etc may also be necessary. Where possible the biological communities should
be classified according to the MNCR biotope classification system although it is
understood that the MNCR system is not complete particularly in subtidal sediments.
Multivariate analysis of the data with techniques such as MDS, TWINSPAN etc will also be
useful in classifying communities and relating them to the environmental conditions. Input
of data into GIS systems is also encouraged.
References
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