The effect of some environmental factors on the distribution of Phytoplankton in the coastal water of Tartous city

This environmental research was conducted on the coastal water of Tartous city for the first time to complement previous studies along the Syrian coast. Sampling station were selected based on their different environmental characteristics from each others on one hand, and their continuous exposure to the sources of pollution (oil, chemical, organic) on the other hand. It hasbeen implemented13sortiesfreelyduring the study period, which lasted fromSeptember2013untilSeptember2014. during which water samples were collected for analysis and determine the concentration of nutrients in, as vital samples to study and determine the types of phytoplankton, which collected, in addition to conducting field measurements of some properties Physical seawater (temperature, pH, salinity, oxygen dissolved concentration). This study has recorded 160 species of phytoplankton in study sites, distributed as follows: 91 species of Chryssophyta, 50 of Pyrrophyta, 11 of Chlorophyta, and 8 of Cyanophyta, their distribution has differed from one site to another and from month to monthaccordingto the differentiation in the environmental conditions.

The Influence of silicate to Nitrate ratio on the diatoms growth at two stations located in the northern part of Latakia coastal water

Experiments were carried out at two stations in the northern part of Latakian coastal water during March 2010, to investigate the influence of Si: N ratios on diatoms growth and to determine the conditions that would generate Si limitation in diatom growth and that might cause a shift from diatom to din flagellate dominance. To achieve that, Natural Phytoplankton were cultured in mesocosm experiments. At the beginning of the experiment, the inorganic nutrients were manipulated to give different inorganic Si: N ratios (ranged between 0, 3 and 7). The results showed that Diatoms were still dominant under these Si: N ratios and Din flagellates remained unaffected, regardless of the above different ratios. The experiment did not show any Silicate limitation to the diatom growth even under the lowest N: Si ratios. Moreover, the species composition of diatoms was affected by the enrichment experiments operated in two stations. Here, the Nitzschia closterium species dominated under both low and high Si: N ratios although their occurrence is not common during the spring phytoplankton bloom at both sites.

دراسة توزع العوالق النباتية تحت تأثير بعض العوامل البيئية في شاطئ مدينة اللاذقية

أستعرض خلال هذا البحث توزع العوالق النباتية في أربع محطات أوقيانوغرافية شاطئية مختلفة بصفاتها البيئية، واقعة بالقرب من مدينة اللاذقية، مع دراسة أهم الخصائص الهيدروكيميائية للمياه المدروسة. كما حددت ١٠٨ أنواع من العوالق النباتية، وزعت على مجموعتين رئيستين كما يلي: ٦١ نوعًا من المشطورات و ٤١ نوعًا من السوطيات النباتية و ٦ أنواع من زمر أخرى.