Research
Field and Laboratory Studies on Four Species of Sea Squirts and their Larvae
The aim of this study was to characterize adult distribution with respect to light and analyze ovary contents in the four seasons of the year. The swimming behavior of Ciona intestinalis, Molgula manhattensis, Ascidella aspersa and Phallusia mammilata larvae against certain abiotic factors were commented. For the field data on adult distributions, one-way analysis of variance (ANOVA) was applied to test for differences in adult orientation, with surface orientation as a fixed factor. Two adult species (Ciona intestinalis and Molgula manhattensis) showed no orientation with respect to light while in the other two species (Ascidella aspersa and Phallusia mammilata) light exerted a significant effects on the orientation and density of individuals. To evaluate among the different species the level of gregariousness found in the field, the number of individuals per clump for each species has been compared using one-way ANOVA, with species as a fixed factor. Artificial heterologous inseminations were carried out.
Statistical Analysis of Some Selected Zooplakton Composition Dwelling Two Pan Marine Ecosystems with A Reference to the Abiotic Factors
Physical and chemical factors of marine ecosystems were measured in Anfoushy and Abu Qir Bay (Mediterranean Sea) Egypt during 2009 & 2010 and Northern and Southern Khobar during 2012 & 2013 to study their effect on the distribution of the zooplankton densities. Seasonal variations of water transparency (Secchi disc reading in cm) ; water temperature (°C) ; total dissolved solids (mg/l) ; total alkalinity (mg/l) ; total hardness (mg/l) ; salinity (g/l) ; chlorides (mg/l) ; total Nitrogen (mg/l) and Tributyl tin (μgg-1) were measured. Samples of the four pan marine beaches were taken at each site, using screw top polypropylene bottles of 1000 ml. capacity. The bottles were transported filled with distilled water and washed out and refilled with sea water at each site. Closing the bottles have been done underneath the water surface so as to make sure that they were completely full. These samples were returned to the laboratory and analyzed within twenty-four hours.
