ECOLOGICAL STUDIES ON COMMERCIAL SPONGES IN WEST OF ALEXANDRIA

ECOLOGICAL STUDIES ON COMMERCIAL SPONGES
IN WEST OF ALEXANDRIA . . ** A.K. KHElRALLAH*, H~K. BADAWI** AND H.M EL-BESHBESHY
.. ZoologyDepartment~ Faculty of science, Alexandria
university. .
•• National Institute of oceanoqraphy and Fisheries,
Alexandria.
ABSTRACT
– ~L…1′. taken ulng flthlng _on ‘r_ tour
….iCll’la· In 8n ,.area .xtending t90 … alone- tM _t.m
lledherr-“ellft coast of Ale.ardrfa t~ det.rllI” the ~.
of tM t”r” ca.-rclat sponQ. types u-ly ‘urkey cup,
IIoney cClltl and Zf_ea em to’.vah.t. the COI'”,..I_ of
‘tMlr eI:udanc~ with the _in “,vi…n.ntal . ‘.tora. TM
ree’ON ~tudied were at 11·1_ denoted -,.., E’~AI_i” .
…. ‘uIe”” -e­ end “‘trM .-. VerlatloN In the total of·
tM -W) IlUItlera .f the three &pongetypN ..re nottc•.t»t.·
..”,. ttl. dfUerefit regions. U-I_.regiun Sl4lPOrtld .,.e
PGFUiatlorw then tttaother reglorw. There _Fe a11lOvarIations tft populatIon ~itlt.. of eadh ca-Merclal
aponge type 1ft the dlff.rent r.olon.. .Turley alp tended to
.re…. towercfa the west.r~·· .’de ….It. Ioney- cOlllb and
Zimocca exhibited fluetuetfona: In densIty alon, the area
Invntlgated.
Th. atudy of the environmental factor. prev.lent In the
area InvestIgated revealed· that high concentrations of
JlIIytoptriton, large surfaee area of rocky and consolidated
substrata and high product’on of sea grassea end green atgae
are Important in controlling the abundance of ~rct81
spongea. loverthelesa, temperature, salinity, coneentration 0’ aooplonkton and percentages of organic and carbonate
content. of tbe bottom sediment. ytelaed significant
correlation “ith sponge abUndance Ifdfcatlnt that these
factors are not of primary iq,ortance In control tIrig the
abundance of cOllIlIercial apongea (n the area Investigated.