الفهرس 
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Abstract
Monitoring of natural communities and their changes over time (Chiappone &
Sullivan, 1994) and the identification of natural fluctuation in communities or population
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exhibit changes induced by anthropogenic impacts (Brown & Howard, 1985).
Subtidal zone is a mosaic of habitats, where structure depends to a great extent on
biotic elements such as macrophytes and this zone is also rich in micro and macro fauna due
to benthic and epiphytic species (Vuille, 1991). Marine flora provides significant feeding,
nursery and refuge habitats for ecologically and economically valuable species in the coastal
zone (Zeiman, 1982 and Thayer et al., 1984). Algal species can affect the distribution and
abundance of various faunal species (Russo, 1989).
Rocky shore communities include both primary and secondary producers (several
trophic levels) with species exhibiting a wide range of life strategies and ecological
requirements. Various components in these communities could therefore be expected to react
to a very wide range of changes in the surrounding environmental factors (Lundalv, 1987).
Coastal macrophytes in coastal waters often host a wide range of different phyla.
Mobile taxa are generally colonizing a wide range of macrophyte than the sessile organisms,
although there relative abundance is often related to the size and morphology of the plant
colonized (Williams & Seed, 1992).
Seagrass meadows constitute an ecological system including a rich variety of faunal
and floral elements. The flora consists of epiphytic micro-and macro algae on the leaf canopy.
The fauna consists of vagile, semi-vagile and sessile organisms occupying different zones on
the meadows. There are some fauna associated with the shoots, others with the rhizomes and
others burrowing with the sediments, within the meadow. There are also visiting organisms
such as fish, which find their food in the meadow, either by grazing on epiphytes or by
predation on animal organisms. Seagrass beds have long been recognized as a shelter, a
surface of attachment and important feeding grounds for juvenile and adult fishes (Carr &
Adams, 1973; Adams, 1976; Livingston, 1982; Bell & Harmelin- Vivien, 1983; Robblee &
Zieman, 1984; Stoner & Livingston, 1984). In addition to providing feeding grounds for
various fish species (Pollard, 1984 and Comp, 1985), these systems function as a refugee and
nursery grounds for larval and juvenile stages of many marine fishes, potentially enhancing
their early growth and survival ( Alien, 1982; Rosenberg, 1982; Joyeux & Ward, 1998). This
nursery function has often been discussed in terms of the dependence on lagoons by some.