سهیل بهربر

In this investigation, the amounts of organic matter, types of sediment and distribution of macrobenthic species in the Boojagh Marine National Park (BMNP) were studied. Sampling was conducted in six transects perpendicular to the beach using a Van Veen grab sampler using cross section of 20 cm with five replications. Samples were collected in five seasons (from summer 2015 to summer 2016). Each transect include three stations at various depths of 1, 5 and 10 meters. Samples were washed and fixed in formalin. Then, they were transferred to a laboratory for sorting and identification of different groups of macrobenthic taxons. The identified species were as follows; Cerastoderma glaucum, Mytilaster lineatus, Pyrgula grimmi, Anisus kolesnikovi, Stenogammarus carusui, Paraniphargoides motasi, Onisimus caspius, Pterocuma pectinatum, Pterocuma sowinskyi, Pseudocuma (Stenocuma) gracile, Naiss sp., Hypania invalida, Manayunkia caspica, Streblospio gynobranchiata, Hediste diversicolor and Amphibalanus improvisus. Evaluation of sediment composition indicated that the highest proportions belonged to sand with an average amount of 89/25%, whereas the lowest proportions belonged to clay with an average amount of 0/26%. with highly significant difference among sand identified with other particles (p<0/01). The average percentage of organic matter in the summer 2015 in the fourth transect at the depth of five meters was significantly lower than that of the others (p<0/01). The highest density of macrobenthos was at the depth of 10 meters. Macrobenthos density was the highest in the summer 2015 and was the lowest in the spring 2016 as compared to the other seasons.

In this study, the distribution of macrobenthos in Boojagh Marine National Park (BMNP) was studied. Sampling was conducted in six transects, perpendicular to the beach, using a Van Veen grab sampler, with five replications. Samples were collected in five seasons (2015-2016). Each transect include three stations at depths of 1 meter, 5 meter and 10 meter. Washed and fixed samples were transferred to the laboratory, sorted and different groups of microbenthic taxons were identified. Mollusca with an average of 588 individuals per square meter, Malacostraca with 225, Polychaeta with 175, Hexanauplia with 109 and Clitellata with 98 individuals per square were identified. Depth profiles showed that the benthos are mostly distributed at 10 meter depth, followed by five and one meter depths. The densest season was at summer of 2015, with 356 individuals per square meter followed by summer of 2016, autumn and winter of 2015 and spring of 2016. Overall, the most macrobenthos distribution was in 10 meter depth. Macrobenthos density in the summer was more and in the spring was less than other seasons.

In this study some of the biological aspect like age and growth, length and weight and longitudinal growth of Cobitis taenia which have been fished in Talar River has been reviewed. Samples were taken from two locations, 20 km apart, from Oct. 2008 up to Sept. 2009. Samples were collected monthly by using an Electro-shocker machine .Collectively 410 speciemen of Cobitis taenia were obtained. Fishes have been examined for sex identification and 158 male , 119 Female and 133 immature have been determined from two locations during one year. This sampels belonged to 4 age groups of females and males. The proportion of male to female was 1/3 to 1. The relation between length and weight of males and females was W=0/671×TL+0/043 & W=1/593×TL+0/061. Growth parameters of Vonbertalanfi equation for males and females fish were as follows: L∞:680/09 K: 0/04 t0:0/106. Difference of Length Frequency distribution among males and females regarding the age were significant (P<0/05) the male fish had more frequency in the short length. The frequency for males, females and immatures was estimated to be32/4, 29 and 38/5percent. The weight and length of females was more than males. Average age for males was 0- 2 years and for females is 0- 3. Dominant age and average age for all fish were estimated to be 1 and 1/07 respectively.