Surveying the density and distribution of Plankton and their role on Aquaculture in the Hassanloo reservoir dam

In the studies of the comprehensive fishery project of the Hassanloo lake, planktonic studies were considered as basic studies to increase the production of fish in this lake.These studies were carried out  during three phases of  sampling  from 2001 to 2005 to this lake in the West Azerbaijan. Plankton sampels were collected with (P.V.C) tube (lenth, 2m), in  Phytoplankton 1 liter water samples (without filtering )and in Zooplankton 30 liter water sample were filtered with a (30 µm) Zooplankton net , Finally  sampels were fixed with % 4 formaldehyde. in laboratory  sampels after preparetion  were identified and counted under  a invert  Microscope. In phytoplankton research, there were 5 phyla and 52 genera and in zooplankton 3 Phyla and 34 genera were identified in this lake.The production indicate seasonally which the peak of phytoplankton density occured in Summer and the Phylum of Bacillariophyta were abundant and among Phytoplankton genera Synedra,  Diatoma, Nitzschia and Navicula showed dominate in water-body. In general the yearly average of  Bacillariophyta  numbers calculated 2494127 / lit. It had  %38 population  during  year. In Zooplankton study results showed that  Rotatoria had  maximum density in Spring  and among  Zooplankton genera Synchaeta , Keratella , Lepadella and Brachionus showed dominate  in  water-body. In general the yearly average of Rotatoria numbers calculated 1298 / lit and it had %66.3 Zooplankton population during year. Comparison of planktonic observations and physical and chemical data of water, showed that  Hassanloo  lake  have  talents and suitable planktonic species for feeding and rearing their fish. Thus, Natural reserves of this source can be used to increase the value of fishery fish.