0 PSU. In other coastal waters of similar conditions like Abu Qir Bay and Dekhaila Harbour, tintinnids formed 27.8% and 65% of total zooplankton respectively, with the dominance of Favella markuzowskii, Stenosemella nivalis, in Abu Qir Bay ( Abdel-Aziz, 2001) and Favella serrata, Tintinnopsis lata in Dekhaila Harbour ( Abdel-Aziz, 2000). Rotifers attained their maximum abundance during summer, constituting 16.3% of the total zooplankton at water temperature of 28°C, salinity 37.0 PSU and pronounced high concentrations of nutrient salts. Zooplankton diversity was positively

correlated with both salinity and nutrient salt concentrations. These relationships suggest that low salinity and low nutrient concentrations decreases zooplankton. In conclusions, not only the discharged water from canals and drains make the harbour at risk, but also the ballast water not less dangerous, and so, we emphasize the need for ballast water PF01367338 management to reduce the risk of future species invasions and further studies should be carried out frequently to monitor any change in species composition since ships arriving at the Western Harbour are increasing annually and also these concerns emphasize the need for activation of the ballast water management IMO Ballast Water Management Conventions to reduce the risk of future species invasions. The authors are indebted to National Institute

of Oceanography and Fisheries, Egypt on the financing of the project “Microbial Selleck LBH589 and plankton estimation in the Western Harbour in relation to some environmental parameters”. They also thank Prof. Manal El Nagar, head of Marine Microbiology Department, for supporting the research project. “
“Spring phytoplankton blooms Isoconazole represent the most important annual impulse in the pelagic food webs in temperate coastal environments (Legendre,

1990). The fate of the organic matter produced in the euphotic zone determines the role of the biological pump in the carbon cycle, and the sedimentation of phytoplankton blooms can strongly influence the benthic habitat in coastal shallow systems (Davoult and Gounin, 1995 and González et al., 2009). Sink deposition of particulate matter is affected by diverse physico-chemical and biological factors such as water column structure: stratified/mixed, temperature, turbidity, phytoplankton density, aggregate formation and zooplankton grazing (Cibic et al., 2007 and Kiørboe et al., 2001, Tamelander and Heiskanen, 2004). In oceans, most of the organic matter produced in the upper layers is consumed before reaching the bottom sediments (Legendre and Rassoulzadegan, 1996 and Wassmann, 1998), while in coastal shallow and well mixed systems, a tight interaction between the production in the water surface and the benthic habitat is commonly observed (Botto et al., 2006 and Dale and Prego, 2002).