Proceedings of the Second Mediterranean Symposium on Marine

Gelidiella ramellosa II - - - - 5.7 0.4
Gigartina acicularis II 4.7 5.8 0.2 - - -
Gigartina tedii II - 2.2 - - - -
Gracilaria corallicola II 0.0 1.7 - - - -
Gonyotrichon spp. II 0.7 - - - - -
Griffithsia schousboei II 0.5 0.5 - 0.2 0.3 0.8
Herposiphonia secunda II - - - 0.3 5.3 0.4
Hypnea musciformis II 2.8 0.2 12.8 0.2 - -
Jania rubens I 28.0 2.8 36.5 19.5 20.7 12.9
Laurencia obtusa II 7.7 0.5 9.8 0.7 4.3 1.3
Laurencia papilosa II - - - - - -
Lomentaria clavelosa II 0.2 - - 0.7 9.0 1.3
Lophosiphonia scopulorum II - 2.0 - - - -
Lithothamnion spp. I 0.7 - - - 0.3 0.8
Peyssonnelia rosa-marina I - - - 0.5 - 4.0
Polysiphonia spp. II 0.3 5.7 2.2 0.3 5.7 0.5
Spermothanmion flabellatum II - - - - 0.5 -
DISCUSSION
The approach to <strong>the</strong> ecological quality status through <strong>the</strong> biotic indices is an old but still
relevant development (Engle et al., 1994; Grall and Glemarec 1997; Borja et al., 2000)
and is based on <strong>the</strong> concept <strong>of</strong> indicator groups (taxonomic or functional) <strong>of</strong> organisms.
Functional was in some cases preferable than taxonomic grouping <strong>of</strong> organisms to
reduce spatial and temporal community variability and to discover patterns without
loosing important information. For example, a universal pattern described by Regier and
Cowell (1972), Murray and Littler (1978), Sousa (1980), Schramm (1999) and
validated also in this study is that highly stressed or disturbed marine environments are
inhabited by annual species with high growth rates and reproductive potential, while
undisturbed marine environments by perennial species with low growth rates and
reproductive potential. This was <strong>the</strong> spark to develop <strong>the</strong> biotic index EEI, based on <strong>the</strong>
functional-morphological model <strong>of</strong> Littler and Littler (1980) and use it to divide marine
benthic macrophytes in two different ecological groups, <strong>the</strong> late-successional (perennials,
ESG I) and <strong>the</strong> opportunistic (annuals, ESG II).
In <strong>the</strong> case study <strong>of</strong> Attika coasts, on <strong>the</strong> basis <strong>of</strong> <strong>the</strong> EEI <strong>the</strong> sampling stations were divided
into four classes <strong>of</strong> ES <strong>of</strong> increasing ES in outward direction, which is in accordance to
environmental conditions in Saronikos Gulf (Simboura et al., 1995). Never<strong>the</strong>less, <strong>the</strong>
results <strong>of</strong> this study have to be validated by similar studies in o<strong>the</strong>r areas.
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