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This study is carried out in the Tyab and Yek-Shabeh creeks in the east, and creeks of the Laft and Khamir in the west of the Hormuzgan province from Sep.2016 to Feb. 2017.Ordination metnods(Canonical discriminate function analysis and principal component analysis) were used to interrelationships between biological and non-biological factors. The studied creeks were classified based on pollutants(Total Petroleum Hydrocarbons(TPH) and Heavy metals) and ecological conditions in three groups: Tyab and Khamir, and Yek-Shabeh and Laft, that is showed the studied factors have the ability to study on the density and diversity of shrimp. From among the six components identified, TPH in Tyab, Laft and Khamir creeks and nitrate and nitrite in Tyab, Laft and Yekshabeh creeks had the most role in relation to shrimp biomass and abundance. Also, among heavy metals in this study, only Iron and lead elements in Laft creek are showed the maximum relationship with biomass and the number of shrimp and banana shrimp among the studied elements. In addition, TPH are did not relationship to the biomass and number of shrimp only in Yek-Shabeh, while in the other three creeks its role has been well defined. TPH and heavy metals did not play a significant role in the number and biomass of shrimp in the creeks of Tyab and Yek-Shabeh(the east of province) unlike Laft and Khamir creeks(the west of province) and the most effects were ecological parameters and bentose communities. In the east of the region, unlike the western provinces of the province, total petroleum hydrocarbons and heavy metals did not play a significant role in the number and biomass of shrimp, and the most effects were ecological parameters and bentose communities.TPH and Heavy metals, with some of the most ecological factors, has had an impact on the number and biomass of shrimp communities the western part of the province (creeks of Laft and Khamir). Also, results of PCA test in evaluating some of the meteorological factors on commercial shrimp catch showed wind parameter had the most negative effect, and rainfall and temperature had a positive effect on shrimp catching. In this study, was highlighted the role of ecological factors as factors influencing on the fluctuations of commercial shrimp catch of the Hormuzgan province in comparison with TPH and heavy metals.Therefore, in order to sustainable management of shrimp stocks in the Hormuzgan province is recommended the control of the factors influencing the biological condition of shrimp in nursery grounds with control of fishing effort. Published |
