New Record Of Crustacean Zooplankton Species In AL-Sinn's Fish Farm-Panias

Crustacean Zooplankton Was Studied In Five ponds In AL- Sinn's Fish farm. As a one Of The Most Important components Fresh Water Ecosystem . The samples of zooplankton were collected During Period From November 2013 To March 2015, By One Sampling a Month.

Study of toxicological sensitivity of three aquatic organisms representing the three major groups of fresh water Zooplankton (Cladocera, Copepoda, Rotifera) to the insecticide Chlorpyrifos

Acute toxicity of the pesticide Chlorpyrifos tests were conducted to determine the Lethal concentration LC50 during 48 hours exposure on three species of fresh water Zooplankton: Brachionus calyciflorus ( Rotifera), Mesocyclops leuskarti (Copepoda) and Daphnia magna ( Cladocera). • It was found that the species Daphnia magna is the most sensitive to the pesticide Chlorpyrifos as the value of 48h-LC50=1.28 μg/L, followed by the species Mesocyclops leuskarti 48h-LC50=28 μg/L while it was observed severe lack of sensitivity of the species Brachionus calyciflorus to the pesticide 48h-LC50=910 μg/L. • Depending on the values of the units of toxicity TU has been shown that the toxicity of the pesticide Chlorpyrifos is from the fourth level = highly toxic (TU = 78.30) for Daphnia, and Level III = acute toxicity (TU = 3.57) for Mesocyclops, while it is the first level = non toxic (TU = 0.11) for Brachionus. • Each increase in the concentration of the pesticide 1.0μg/L lead to increase the mortality rate in the species studied about: Daphnia magna ، % 68.79 Mesocyclops leuskarti ، % 0.22 Brachionus calyciflorus % 0.0468 As a result, we can expect that the arrival of the pesticide to aquatic ecosystems will affect the whole bio-community in these ecosystems and the inter their relationships, which in turn could be the cause of the disruption of the ecological balance with vague consequences that are difficult to understand its dimensions.

First record of parasitic copepoda on free – living fish in Lake of 16 Tishreen Dam

The study included 132 Free – living fish in Lake of 16 Tishreen Dam, collected randomly during the period from 22/11/2011 until 22/10/2012, on average once a month, for detecting the infection of parasitic copepoda, and determine the distribution rate, and their effect on the fish productivity.

التوزّع العمودي لمجذافيات الأرجل Copepoda و تغيّراتها النوعية و الكميّة خلال فصلي الصيف و الشتاء في المنطقة الشاطئية لمدينة جبلة

Vertical sampling process took place to Copepoda during the summer and winter of 2009 and 2010 from Alzzouzo castle which is located in the coastal region of Jableh city. This region has special environmental properties. Sampling was accompanied with measuring water temperature, salinity, and dissolved oxygen in the water. The total number of samples studied in all areas of study is 106 samples. 100 species were identified during the summer, while 89 species were identified during the winter; most species belongs to the order of Calanoida. It was noted by the study that most species appeared in two seasons together, while some species appeared in the season without the other. It was also noted that the abundance of Copepoda was higher in summer with an average of (5314 individual / m 3), while the average in winter was (4353, 40 individual / m 3). It was clear from the study that the station near the beach was less diverse and more prolific than the offshore station during the summer and winter together.

Two Species were recorded from Copepoda in Mshannaf Dam (Assweida - Syria)

Copepoda has a great importance in the environement because of the important place it has in the food chain, and because it determines the nutritional situation of the lakes and filtration of Phytoplankton, deteruratus and bacteria.