Estimation of population dynamics parameters of Scomberomorus commerson using modal progression method in the Hormouzgan province waters

Scombermorus commerson is one of the most important commercial fish species in the Persian Gulf and Sea of Oman. To arrange for a sustainable fishing pattern, growth parameters, mortality and exploitation rates of the fish were estimated. Fish length data were collected from 4515 fishes, science April 2007 to March 2008 in three major artisanal fish-landing sites Bandar Lengeh, Bandar Abbas and Bandar Jask in Hormouzgan province waters. The Von Bertalanffy growth parameters (L∞ K and t _(0)) were estimated at 150.24 (cm), 0.66 year ^(-1) and -0.157 year, respectively. The results showed that S. commerson grows very fast in the first 2 years. The results indicated that S. commerson attains its fork length 80.3 cm at the end of first year. The fork length attained at the end of the second, third and fourth years were 114.1, 131.6 and 140.6 cm, respectively. Growth performance index (f) was calculated at 4.1 which were in agreement with the findings of the other studies in the Indian Ocean. Total, natural, fishing mortality and exploitation rate were estimated at 2.11, 0.67, 1.44 year ^(-1) and 0.64, respectively. Five cohorts were distinguished based on Bhattacharya's method

Nickel concentration in Penaeus indicus from Jask coastal waters, Persian Gulf

We assessed the metal-accumulating ability of the shrimp Penaeus indicus for Nickel (Ni) in 2008. Shrimps were seasonally (autumn and winter) collected from Jask coastal area, East of Hormuzgan province in the Persian Gulf. The samples were washed with seawater and dried with the help of freeze dryer and digested using a microwave digester in a super-pure nitric acid solution. The Nickel concentration was determined with Atomic Absorption Spectrometers (AAS). The result showed the mean Nickel concentration of male and female in autumn and winter were 0.007-0.084 and 0.007-0.087µg/g of dry weight, respectively. No significant differences in concentrations of Nickel in shrimps (male and female) and seasons (autumn and winter) were detected (P>0.05)

Water quality assessment in inlet and outlet channels of shrimp farms in Tiab Area, Hormozgan Province

The shrimp farming industry has rapidly expanded in the south of Iran and in particular in the Hormozgan province during the past decade. We studied physico-chemical parameters of water in outlet and inlet channels of shrimp farms in Tiab during July-December 2000. Water samples were collected monthly at four stations during the harvest period. The parameters assessed included pH, salinity, dissolved oxygen, nitrate, nitrite, ammonia, phosphate, total phosphate, total suspended solids and chlorophyll a. The variation of above parameters were determined to be 7.62 - 8.19, 42.75 - 52.55ppt, 2.8 - 8.3mgil, 4.46 -0.66p,mil, 0.214 .64141, 0.12-2.0711m/1, 0.13-16.1 tili/1, 0.59-10.5 µm/l, 22-121 mg/1and 0.43-5.1311m/1 respectively. Results of the analyses showed that salinity, dissolved nutrient, T.S.S and chlorophyll a in the effluent were significantly higher than the influent water (P<0.05). A significant correlation was also found between chlorophyll a and nitrate, phosphate and suspended solid concentration (P<0.05). Comparison of the results with the standards showed that parameters are currently within acceptable limits

Determination of organic pollutants in sediment & some commercial species biota from eastern waters of Hormozgan province

This survey was conducted to determine the petroleum pollutants in sediment & some commercial aquatics of species in eastern waters of Hormozgan province during 2006-2008. We have selected 3 stations at 5, 10 and 20 meters depth in each of Sirik, Kuh-e-mobarak and Jask area. The selected biota were Penaeus indicus & Psettodes eruemi.Selected components of PAHs in sediment & biota samples were: Naphthalene (Na), Acenaphthylene (AcPY), Acenaphthene (AcP), Fluorene (FL), Phenantheren (PHEN), Anthracene (AN), Fluornthene (FLUR), Pyrene (PY), Benzo(a)anthracene (BaA), Chrysene(CHRY), Benzo(b) fluoranthene (BaF), Benzo(k)fluoranthene (BkF), Benzo(a) pyrene (BaP), Dibenzo(a,h)anthrancene (dBAn), Benzo(ghi)perylene (BPe), Indeno (1,2.3-cd)pyrene (IcdP) . Our results were: Based to our results Bioaccumulation of PAHs didn't relate to sex and length of selected biota. Percent of naphthalene as a PAH with two rings has a significant difference against other PAHs in all areas. High ratio of HPAH to LPAH, show the combustion source of PAHs. Values for total PAHs at shrimp in Sirik, Kuh-e- mobarak & Jask area were 349.9 ±236.7, 809.1± 605.4 & 1015±1300.1 ng/g. Values for total PAHs at Psettodes eruemi, in Sirik, Kuh-e- mobarak & Jask area were 494 ±460.8, 1465.3±1678.2 and 292.3±400.7 ng/g respectively. In shrimp samples, the values for total PAHs had significant difference between Jask & Kuh e-mobarak, whereas for Psettodes eruemi, the significant difference was observed in Jask & Kuh-e-mobark. In sediment, concentration of total PAHs and their components didn't show any significant difference with area and depth of sampling at 95% confidence level. Average concentration of total PAHs and their components with 2, 3, 4, 5and 6 rings were 279.7±117.4, 4.5± 9.3, 6.2±7.1, 5.4±1.4, 263.6±113.9 respectively. Based to NOAA standards, pollution level of sediment is lower than ERL values

Assessing Heavy Metals Pollution of the Mangrove Sediments along Tidal Flat of the Mehran River Delta, Persian Gulf

The relationship between the concentration of heavy metals and physicochemical factors was studied in the fine-grained sediments of the tidal section of the Mehran delta where mangrove trees have grown. Surface sediments of the tidal zone of the Mehran delta were sampled. The grain size distribution, calcium carbonate, organic matter contents, pH/Eh, and heavy metals concentration were determined in the mud fraction of the sediments. The presence of high calcium carbonate in sediments is an effective factor in the abundance of Mn, Cd, and Pb. Clay and organic matter as adsorptive have contributed to the high concentration of Zn, Cu, while Fe oxy-hydroxides have affected the concentration of Co, Cr, and Ni. According to the index of Enrichment Factor (EF), the average enrichment of the elements in the studied sediments from high to low order is Cr, Ni, Cd, Zn, Mn, Pb, Co, and Cu. According to the Pollution Load Index (PLI), none of the delta sediments including sediments from inside and outside of the mangrove forestare classified as polluted to the heavy metals. According to the Igeo Index, most samples, and only Cd, Cr, and Ni show slight pollution in some samples. Accordingly, there is no current threat of contamination of potentially toxic elements of natural and anthropogenic origins to the mangrove environment and Mehran delta