جستجوی مقالات مرتبط با کلیدواژه "hormuzgan" در نشریات گروه "زیست شناسی"

The present study aims to recognize dhow prawn trawl by-catch from Hormuzgan coastal waters (Northeast Persian Gulf). Sampling was carried out of 36 hauls by using traditionally wooden dhow among prawn fishing season in 2011. The catch composition consisted of 31.66% target species prawns, mainly banana prawn (Penaeus merguiensis) and 68.34% by-catch. The total by-catch was 4,622.67kg comprised of 56 species and 37 families. Species composition of by-catch was 81.08% Teleostei, 0.1% Elasmobranchs and 18.8% Invertebrates. Ulmaridae, leiognathidae and Mullidae were the most abundant families with mean CPUE of 10.06, 9.97 and 7.73 kg/hour, respectively. CPUE, Occurrence indices and catch percentage of species (based on Wt %) have been calculated. Prawn-toby- catch ratio was computed at 1:2.15. It was estimated that annual volumes of the entire fleet dhow prawn trawls in Hormuzgan coastal waters consisted of 5,728 tons of by-catch.. The investigation of the by-catch showed the large pressure on commercial and non-commercial fish stocks in the fishing grounds of northern Persian Gulf; Therefore, fishery managers need to consider other species when determining catch or effort limits, prawn fishing season and area restrictions.

The objective of this study was determining the heavy metal contents in sediment along the coastlines of Hormuzgan province. Sediment constitutes are important part of aquatic ecosystems. They provide habitat for benthic organisms and could be a significant sink as well as a potential source of contaminants. Three sources of heavy metals pollution in this area are industry, natural mineralogy of soil and oil. The levels of heavy metals (Pb, Cd, Cu, Ni) have been investigated over a 4 season period at 9 sites. We collected sediment samples from a depth of 0-10 cm. Heavy metals assessed by the atomic absorption spectrophotometer. The results showed Pb, Cd, Cu, Ni concentrations in the sediment ranging from 3.00 to 28.00 g/g, 2.96 to 10.11 g/g, 2.60 to 11.27 g/g and 8.03 to 105.30 g/g, respectively. Seasonal study showed that pollution levels in sediments at spring and summer were more than autumn and winter. The heavy metal concentrations lead to the following ranking: Pb> Ni> Cu> Cd. Based on Pollution Index (MPI) values, our result indicated that station 9 was polluted area and station 2 was unpolluted area.