In seeking to gain an understanding of the community structure at and between sampling sites within the survey area, Sea-nature Studies might apply some, or all, of the following to the data set in question:
The number of species at each site and the abundances in which they are found can be examined in a variety of ways. The first three indices are expressions of these two parameters and are routinely used to help describe macrofaunal communities.
Identifying the most abundant taxa from a particular location, perhaps simply as a ‘top ten’ list is an excellent method of identifying those animals which are characteristic of the conditions there. This provides a link between the reductive nature of statistical analysis and the complex ecology behind it.
Multivariate analysis is a powerful way of identifying patterns in the often large, species/ abundance data matrix produced from a survey. Used in conjunction with the other forms of data interogation and physico-chemical information it can be critical in building a useful picture of the ecology of the area under study.
Lastly the more recent addition to the suite of analytical techniques is the ITI or infaunal trophic index. Based on the feeding types of the fauna encountered it seeks to provide an indication of the ‘health’ of marine benthic communities.
