الفهرس 
CHAPTER I INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Coastal area, particularly lagoons have been described in the international literature as typical locations where sediment-associated pollutants (e.g., heavy metals) can be accumulate due to anthropogenic activities. Recently, there is an increasing shift away from the strict reliance on chemical measurements to assess the health of ecosystems. Biological communities appear to provide a direct means of observing the impact of contaminants. The present study has been conducted in order to evaluate the degree of pollution and its influence in the benthic foraminiferal community and mollusca in the Manzala Lagoon, by assessing the heavy metal concentrations and the response of benthic foraminifera to heavy metal pollution as well as the gastropods Bulinus (Isidora) truncates, Bellamya unicolor, Biomphalaria alexandrina, B. glabrata, B. pfeifferi, Melanoides tuberculata and Lymnaea columella are of considerable importance because the function Cercaria pusilla, Fasciola hepatica, Schistosoma mansoni, Schistosomasis transmission and Schistosoma haematobium disease vectors. This work is the first of its kind for the Manzala Lagoon. High concentrations of metal pollutants are recorded in the upper 20 cm of the lagoon sediments, probably from industrial sources. Based on the concentration and toxicity status, some heavy metals show alarming toxicity levels and it is considered as one of the most hazardous pollutants. The largest consumer of water, agriculture is also a contributor to water pollution. Drainage water seeping from agriculture fields is considered non-point sources of pollution. These non-point sources are, however, collected and concentrated in agricultural drains and become point sources of pollution for the Manzala Lagoon. Major pollutants in agricultural drains are salts; nutrients (phosphorus and nitrogen); pesticide residues (from irrigated fields), pathogens 040 (from domestic wastewater), and toxic organic and inorganic pollutions (from domestic and industrial sources). To achieve our goals, sedimentological, geochemical, mechanical analysis and paleontological studies were carried out. Seventeen subsurface samples were collected to study grain size, total organic matter (%TOM), % Ca CO3, total metal concentration of Cu, Pb, Mn, Zn, Fe, mollusca and foraminiferal investigation were analyzed. Organic matter showed a highly positive correlation with carbonate content and clay during winter season. Also with iron, silt (+ve correlated) and sand (-ve correlated) during spring season, and also it showed a moderately positive correlation with lead, silt during winter season, and also with carbonate, clay during spring season. Organic matter is moderately correlated with silt (+ve correlated) and sand (-ve correlated) during summer season.