الفهرس 
Introduction and Review of LiteratureOnly 14 pages are availabe for public view
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Abstract
Ecological studies were carried out on seagrass communities in
Wadi El Gemal National Park in the southern of Egyptian Red Sea
coast. A total of 26 meadows of seagrass were marked, mapped and
seagrass diversity and abundance were investigated. Eleven species of
seagrasses were recorded; four species were new records to the whole
Red Sea, the Egyptian waters of the Red Sea and WGNP. Halodule
pinifolia (Miki) den Hartog is newly recorded to the whole Red Sea
(Red Sea proper, Gulf of Suez and Gulf of Aqaba), while Enhalus
acoroides (L.f.) Royle, represents a new record to the Egyptian waters
of the Red Sea and Halophila decipiens Ostenfeld and Cymodocea
serrulata (R.Brown) Ascherson were recorded for the first time in the
area of WGNP. The meadows areas ranged between 0.024 ha and
498.2 ha with total area estimated 1783.08 ha. The seagrass coverage
ranged between (82.5% ± 8.7) and (17.5% ± 8.0) in different sites.
However, the higher overall mean coverage was recorded at sheltered
sites than exposed ones. The total coverage of seagrass found to be
higher at shallower and deeper waters, rather than the middle depths
of 5-20m. Halphila stipulacea was the most dominant species in both
26 studied sites and the 5 studied depths (0-25m). 8 sites were selected
to study the seasonal variations through 6 seasons between fall 2006
to winter 2008. The annual mean for both shoot & rhizome
biomass/m? at different sampling sites has shown that
Thalassodendron ciliatum (Hamata) had the highest biomass, while
Halophila decipiens (Ras Bughdadi A) had the lowest value. 12
species of associated macroalgae were recorded at different studied
sites. Seagrasses and algae showed obvious seasonal changes with
nearly uni-modal seasonal pattern. A total of 45 macro-invertebrate
species were recorded. Faunal composition showed regional
differences. Most of the species were recorded at Hamata site. Species
similarity between different sites appeared to be low. The algal
epiphyte biomass was greatest during spring 2007 at Qulaan site
which was dominaned with Thalassia hemprichii. While the lowest
biomass recorded during winter 2007 at Ras Bughdadi C site which
was dominated by Cymodocea serrulata.