THE IMPACT OF ANTHROPOGENIC ACTIVITIES ON THE PHYSICAL AND CHEMICAL CHARACTERISTICS OF SURFACE SEDIMENTS IN SOME COASTAL LAGOONS ALONG THE EGYPTIAN RED SEA COAST

THE IMPACT OF ANTHROPOGENIC ACTIVITIES
ON THE PHYSICAL AND CHEMICAL CHARACTERISTICS OF
SURFACE SEDIMENTS IN SOME COASTAL LAGOONS ALONG
THE EGYPTIAN RED SEA COAST
HASHEM A. MADKOUR*, AHMED W. MOHAMED* AND ABU EL-HAGAG N.
AHAMED **
* National Institute of Oceanography and Fisheries, Hurghada Research Station, Red Sea
Branch.
** Geological Survey of Egypt
[email protected]
Keywords: Texture, pollutants, sediments, coastal lagoons, Red Sea, Egypt.
ABSTRACT
Forty-two sediment samples were collected from Abu-Shaar, Abu-Galwa, Umm alHuwaytāt and Marsa Shūni lagoons located along the Egyptian Red Sea coast. Several
investigations including nature and geochemistry of surface sediments were carried out.
Grain size characteristics reflect the restriction of sand rich with coral debris in Abu-Shaar
and Abu-Galawa lagoons. Consequently, The sediments of Abu-Galawa and Abu-Shaar
lagoons have the highest carbonate content due to the dominance biogenic sediments from
surrounding coral reefs and relatively of terrigenious influx. The mud content recorded high
values in Umm al-Huwaytāt and Marsa Shūni lagoons compared with the other two lagoons
due to high contribution of terrigenous materials from wadies and some human activities
especially near at Umm al-Huwaytāt lagoon by shipment activities in Abu-Tartour Harbour.
The sediments of Marsa Shūni lagoon have the highest total organic matter content
compared to the other three lagoons resulting from the high contribution of terrestrial input
by Wadi El-Shūni . Grain size is the main controlling factor for the organic carbon
enrichment. On other hand, The phosphorus content of sdiments sampled in Umm alHuwaytāt lagoon recorded the highest values due to phosphate shipments operation in AbuTartour Harbour. The investigation of distribution of the heavy metals Fe, Zn, Cu, Pb and
Cd in surficial sediments of the coastal lagoons indicated that the degree of metals pollution
is caused by anthropogenic activities and or by natural impacts by wadies. This study
provides knowledge about nature and geochemistry of sediments and the extent of the
pollution degree of the metals to represent primary base line data efor managers to follow
any anthropogenic impacts, and better assessing the needs for remediation by detecting any
changes in future.