Proceedings of the Second Mediterranean Symposium on Marine
Proceedings of the Second Mediterranean Symposium on Marine
Proceedings of the Second Mediterranean Symposium on Marine
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LITTORAL BENTHIC COMMUNITIES AS INDICATORS OF<br />
ENVIRONMENTAL QUALITY IN MEDITERRANEAN WATERS<br />
Susana PINEDO, Maria GARCIA, Maria. Paola SATTA, Xavier TORRAS and Enric<br />
BALLESTEROS<br />
Centre d’Estudis Avançats de Blanes. Acc. Cala Sant Francesc 14, 17300 Blanes, SPAIN<br />
ABSTRACT<br />
Sampling <str<strong>on</strong>g>of</str<strong>on</strong>g> benthic communities from <str<strong>on</strong>g>the</str<strong>on</strong>g> Catal<strong>on</strong>ia rocky littoral (NW <str<strong>on</strong>g>Mediterranean</str<strong>on</strong>g>)<br />
was carried out in 1999-2000 to study <str<strong>on</strong>g>the</str<strong>on</strong>g> envir<strong>on</strong>mental quality <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>the</str<strong>on</strong>g> waters, using <str<strong>on</strong>g>the</str<strong>on</strong>g><br />
organisms as bioindicators, and DCA analysis as ordinati<strong>on</strong> method. Coverage <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>the</str<strong>on</strong>g><br />
main organisms was used as descriptors <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>the</str<strong>on</strong>g> ecological state. Cystoseira mediterranea<br />
was <str<strong>on</strong>g>the</str<strong>on</strong>g> dominant species in <str<strong>on</strong>g>the</str<strong>on</strong>g> north coast, whilst <str<strong>on</strong>g>the</str<strong>on</strong>g> central and south coasts were<br />
mainly dominated by Corallina el<strong>on</strong>gata and Mytilus galloprovincialis. Samples in<br />
reference z<strong>on</strong>es (n<strong>on</strong>-polluted areas, with almost nil human influence) were also<br />
introduced in <str<strong>on</strong>g>the</str<strong>on</strong>g> analysis to compare <str<strong>on</strong>g>the</str<strong>on</strong>g> water quality <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>the</str<strong>on</strong>g> different stati<strong>on</strong>s in <str<strong>on</strong>g>the</str<strong>on</strong>g><br />
Catalan coast with <str<strong>on</strong>g>the</str<strong>on</strong>g>se <str<strong>on</strong>g>of</str<strong>on</strong>g> “pristine” areas. Our results are compared with previous data<br />
obtained in 1982. We observe changes in <str<strong>on</strong>g>the</str<strong>on</strong>g> structure <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>the</str<strong>on</strong>g> littoral communities since<br />
1982, with an apparent increase <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>the</str<strong>on</strong>g> envir<strong>on</strong>mental quality. There is a decrease in <str<strong>on</strong>g>the</str<strong>on</strong>g><br />
abundance <str<strong>on</strong>g>of</str<strong>on</strong>g> green-algae but we do not observe an increase in <str<strong>on</strong>g>the</str<strong>on</strong>g> abundance <str<strong>on</strong>g>of</str<strong>on</strong>g><br />
Cystoseira. These changes can be related to <str<strong>on</strong>g>the</str<strong>on</strong>g> implementati<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>the</str<strong>on</strong>g> management <str<strong>on</strong>g>of</str<strong>on</strong>g><br />
<str<strong>on</strong>g>the</str<strong>on</strong>g> residual waters since 80’s years.<br />
KEY-WORDS: Benthic communities, bioindicators, envir<strong>on</strong>mental quality, littoral,<br />
<str<strong>on</strong>g>Mediterranean</str<strong>on</strong>g> Sea<br />
INTRODUCTION<br />
Benthic organisms integrate <str<strong>on</strong>g>the</str<strong>on</strong>g> effects <str<strong>on</strong>g>of</str<strong>on</strong>g> l<strong>on</strong>g-term exposure to natural and<br />
anthropogenic disturbances (Borowitzka, 1972). Thus, <str<strong>on</strong>g>the</str<strong>on</strong>g> use <str<strong>on</strong>g>of</str<strong>on</strong>g> benthic communities<br />
in marine polluti<strong>on</strong> assessments is based <strong>on</strong> <str<strong>on</strong>g>the</str<strong>on</strong>g> c<strong>on</strong>cept that <str<strong>on</strong>g>the</str<strong>on</strong>g>y reflect not <strong>on</strong>ly<br />
c<strong>on</strong>diti<strong>on</strong>s at <str<strong>on</strong>g>the</str<strong>on</strong>g> time <str<strong>on</strong>g>of</str<strong>on</strong>g> sampling but also c<strong>on</strong>diti<strong>on</strong>s to which <str<strong>on</strong>g>the</str<strong>on</strong>g> community was<br />
previously exposed. There are numerous traditi<strong>on</strong>al methods that identify disturbances in<br />
s<str<strong>on</strong>g>of</str<strong>on</strong>g>t-bottom communities using macr<str<strong>on</strong>g>of</str<strong>on</strong>g>auna as bioindicators (e.g. Pears<strong>on</strong> and<br />
Rosenberg, 1978). For rocky benthic organisms, macrophytes are <str<strong>on</strong>g>the</str<strong>on</strong>g> most interesting<br />
group as integrators <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>the</str<strong>on</strong>g> envir<strong>on</strong>mental quality (e.g. Levine, 1984). Studies <strong>on</strong> <str<strong>on</strong>g>the</str<strong>on</strong>g><br />
effect <str<strong>on</strong>g>of</str<strong>on</strong>g> sewage outfalls and industrial dumping <strong>on</strong> macroalgae reveal <str<strong>on</strong>g>the</str<strong>on</strong>g> sensitivity <str<strong>on</strong>g>of</str<strong>on</strong>g><br />
some brown algal species, mainly <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>the</str<strong>on</strong>g> genus Cystoseira to polluti<strong>on</strong> (e.g. Bellan-<br />
Santini, 1968; Soltan et al., 2001).<br />
Species <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>the</str<strong>on</strong>g> genus Cystoseira dominate <str<strong>on</strong>g>Mediterranean</str<strong>on</strong>g> littoral communities (Feldmann,<br />
1937) but <str<strong>on</strong>g>the</str<strong>on</strong>g>y are replaced by Corallina el<strong>on</strong>gata or Mytilus galloprovincialis in disturbed<br />
or polluted envir<strong>on</strong>ments (Bellan-Santini, 1968; Ballesteros et al., 1984). These two<br />
ACTES DU DEUXIEME SYMPOSIUM MEDITERRANEEN SUR LA VEGETATION MARINE (ATHENES, 12-13 DECEMBRE 2003)<br />
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