Ultra-violet Absorption Measurement as a Rapid Toolfor Tracing Dispersion of Sewage E1Jluent and for Classification of Water Masses in Two Red Sea Coastal Lagoons, Jeddah

Ultra-violet Absorption Measurement as a Rapid
Toolfor Tracing Dispersion of Sewage E1Jluent and
for Classification of Water Masses in Two Red Sea
Coastal Lagoons, Jeddah
By
Osman A. EI-Rayis·
Chemical Oceanography Department, Faculty of Marine Sciences, King Abdul-Aziz
University,P.O.Box 1540,Jeddah 21441, Saudi Arabia
Abstract
‘The ‘U1l·aEsor6anu was measured in water samples cofkctd iuring six ssuccessioe cruises witfUn one
year from two SauLian sewage·affectd fJori·fiKJ fagoons (.7lr6aun ani’RJayat .7l{ SfuWaE) , Jdtfali.. ‘The
li.ytfrocfumica£ ti.t.ments, salinity, pfwspliau ani ammonia were also measured: On tk surfau or on tk oerticai scales, tk iistri6ution pattern of t~ ‘U1l·aEsor6anu an4 tliat for tk other !i.yirocfurnica£ ef.t.ments coincitlei on eacIi.otli.er to a great t)(tent. On tk surface water scale, it was easy to iefine tk iirection of t~
spreatfd iisdwTgd urastetuater. On t~ vertica£ scaie, tli.ru water layers can 6e easify iitin.guis~{, surface
seauuuer layer iuutd witli. sewage effluent [contained’ li.igli.oaiues of tk ‘U1l·a6sor6anu, pli.ospli.ate ani
ammonia), isuameduu« u.ss iuuted seatuaur £oyer(u.sspo{{utd) and bottom saline ‘0{4water £ayerwitfi. e~:
ceptiona£ li.igli.oalius of tfi.eother tli.ru parameters. ‘I1iissituation preoaded’ for most of tfi.e times of tlit year
in tfi.e fagoon ~pt iuring tfi.e intermittent ftusli.ing periods occured in winter an4 early spring, wli.ere tlit
stratification is iistur6d. ‘The ‘U1l·a6sor6anu is iirectly measured in tli.ewater sampu.s witli.out any cfumi·
cat pre· treatments ani nutfs no special traind person.