Medcore output on the midlittoral and sublittoral benthic communities
Authors: Partner 5
Various activities have been carried out on the midlittoral and sublittoral benthic communities of the Mediterranean sandy beach environment, in the context of the MEDCORE Project. The results deriving from these activities revealed the following conclusions, which can be of potential managerial use in the future sandy beach habitat planning:
1. The Mediterranean sandy beach ecosystem and especially its mid- and sublittoral zones seem to be neglected despite their economic and societal importance. Most of the scientific effort spent on these habitats derives from “one-off ” sampling design and thus the information obtained is not enough to describe its structure and function.
2. The “standard” diversity indices (Shannon’s H’, Pielou’s J, Margalef’s d) do not seem to provide plausible results or any kind of pattern that can be used for socio-economic and managerial purposes; contrary, the application of the Taxonomic Distinctness indices appears to be of potential use in producing plausible patterns on a pan-Mediterranean scale. Consequently, these indices seem to be unique in providing useful information for the management of this system, at least for the time being. However, the impoverished inventory produced by the poorly studied sandy beaches appears to be a major obstacle in their wider use.
3. The multivariate techniques perform much better than the diversity indices; these techniques are able to provide with useful patterns from the managerial point of view, both at local and at the pan-Mediterranean scale; the overall pan-Mediterranean pattern shows a tentatively emerging “zoogeocline ” from the Eastern to the Western Sectors of this Regional Sea. At the local scale, patterns show a clear division of the midlittoral from the sublittoral zone or can distinguish different regimes along well-defined environmental gradients.
4. The “taxonomic sufficiency ” (e.g. the taxonomic level by which acceptable results are derived - less effort spent) approach implies that the taxon of Polychaetes has a great potential as an indicator taxon both in the calculation of the Taxonomic Distinctness indices and in the application of the various tecniques.