علوم زیستی دریا
shafa hoveizavi; Babak Doustshenas; Gholamreza Eskandari; Ahmad Savari; Hossein Mohammadasgari
Abstract
The main purpose of this study was to describe and estimate the seasonal pattern of discard fish in the waters of the Persian Gulf coasts in Khuzestan. sampling was carried out Monthly by using fishing boats in the waters of Khuzestan province for one year in fishing areas of Lifeh, Boseif, Khure-mussa ...
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The main purpose of this study was to describe and estimate the seasonal pattern of discard fish in the waters of the Persian Gulf coasts in Khuzestan. sampling was carried out Monthly by using fishing boats in the waters of Khuzestan province for one year in fishing areas of Lifeh, Boseif, Khure-mussa and Bahrakan.Discard fish samples were included 61 species from 37 families, nearly 39 percent commercial and 61 percent of non- commercial species. Rayfish and catfish have been observed in most fishing nets. Average size of most species particularly bony fish were under 15 cm. The amount of discard fish per unit of fishing effort is not significantly different between seasons. The highest portion of the catch belongs to Rayfishes. Total discard fishes of gillnets were estimated 3162 tones. Total weight of commercial fishes with small size in trash fish was estimated 225 tones. The rate and proportion of discard fish in total catch of gillnet was estimated 0.23 and 0.31 respectively. Chondrichthyes with 12 species and 60% of gillnet catch has the highest percentage of discard fish of gillnet. A large number of commercial species with small size such as Otolithes ruber (Schneider, 1801), ( Scomberomorus commerson (Lacepede, 1801) and Scomberoides commersonnianus(Lacepede, 1801) could be due to the role of nursery grounds in Khuzestan coastal waters.
shafa hoveizavi; hossein pasha zanusi
Abstract
Ecological health is the most important component of the biological health. Macrobenthos invertebrate are the most important organisms in aquatic ecosystems that are used for determination of biological health. Benthic indices base bye data simplifying and shows a set of biological variable as a quantified ...
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Ecological health is the most important component of the biological health. Macrobenthos invertebrate are the most important organisms in aquatic ecosystems that are used for determination of biological health. Benthic indices base bye data simplifying and shows a set of biological variable as a quantified variable that made the interpretation of data easier, one of this indices is BOPA index that give from ratio of opportunistic Polychaeta to Amphipoda. The higher value of this index shows environmental pollution. The value of BOPA index showed significant difference between stations(p