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International Journal of Marine Science 2014, Vol.4, No.39: 1-4
http://ijms.biopublisher.ca
2
terms. However, the composition and structure of
coral communities largely corresponded to the classic
reefs. Brief description and analysis of these reefs is
dedicated to this article.
1 Methods and Material
1.1 Sampling site
Using SCUBA equipment were studied the species
composition and distribution of scleractinian and mass
species of macrobenthos (a little more than 400
species), structure of communities in every zone of
reefs at islands Socotra (Indian Ocean)and some
islands of Baitylong archipelago (South China Sea,
Figure 1).
Figure 1.Schematic section of reef. A) profile and zonation;
I-IV) bionomical zones, a) facies A.
microphthalma
and
S.
pistillata
, b) facies
L.
phrygia
and
P. lutea
, c) facies
L.
phrygia
and S.
trocheliophorum
, d) facies
P.
abdita
and
P. camersoni
;
Arabic numerals along the abscissa - number of species of
scleractinian in the zone, B) degree of corals covering the
substrate (1) and ratio of branching (2), mass colonies (3);
along the abscissa is distance from beach, m; along the ordinate
is degree of covering of substrate, %, number of colonies.
1.2 Transected method
Surveys have been done
according using frames and transects method (Loya
and Slobodkin, 1971). Two hundred meters transects
with the foot age marking were mounted in the open
and closed bays, on the headlands, near rocky, stony
and sandy shores in order to maximally cover the
diversity of reef communities in the region of survey.
Along the transects, on every square meter the
quantity of branchy, massive, incrusting and
funnel-form colonies of scleractinian, degree of
substrate covering with corals in the form of a frame
divided into 100 squares, and the quantity of mass
species of mollusks and echinoderms were accounted.
1.3 Identification of corals
(228) species was made
for analysis of species composition and structure of
community of coral reef survey methods (Veron and
Smith, 2004; Latypov, 2006a; Weinberg, 1981).
2 Results
2.1 Reef of Socotra Island
Coral reefs of Socotra Island do not have the usual
reef zonation. The corals cover the substrate the low
crust almost without changing his profile (Figure 2).
There are the first zone consists of algae and coral
with spots of eel-grass and corals. The zone is 20-60
m wide. The second zone is a steep section of the
bottom with small boulders of insular rock and
projections of beach rock between which there are
accumulations of coarse-grained sand, organogenic
detritus, and fragments of corals. The settlements are
individual, polyspecific, with spots of large branching
colonies of no particular species. This zone is 40-50 m
wide. The third zone is also steep, with a hardly
noticeable sloping section of sandy bottom
periodically covered with fragments of dead coral. The
settlements of scleractinian are dense and the large
colonies are several meters in diameter and height.
Bioherms and settlements of soft corals are broadly
developed in this zone, which is up to 100 m in width.
The fourth zone has an even sandy bottom, with
numerous remains of dead corals on which colonies of
scleractinian, alcyonarian, and algae, have settled. The
soft corals frequently form dense polyspecific
settlements.
The morphological peculiarities, structure, composition,
and distribution of corals make it possible to separate
the following zones on reefs of Socotra Island (Figure 3).
Alga-Coral zone
(I). Zone of distinct domination by
algae
Galaxaura
spp. among which different colonies
of scleractinian are distributed, notably massive and
crusted forms of growth. These algae form spotted
settlements, which cover the surface substrate by
about 40%. The degree of coral coverings does not
exceed 1-3%. The most common are scleractinian
Psammocora profundacella, Stylophora pistillata
, and
Leptastrea purpurea
. In general, habit, assembly of
taxon’s, and growth forms of corals, the zone is
comparable with the boat channel zone (Bouchon,
1981). It is 20-60 m wide from the lower horizon of
the littoral to a depth of 2 m.