جستجوی مقالات مرتبط با کلیدواژه « bushehr » در نشریات گروه « شیلات »

The process of catching fishing gear that goes out of control is called ghost fishing. Abandoned, lost or discarded fishing gears (ALDFG) can cause adverse economic and environmental effects. Passive fishing gears, such as cages, produce more severe effects after being released into the water. Gargoors are one of the types of cages, which every year a large number of them are left in the sea in the Persian Gulf and the Oman Sea, for various reasons. In recent years, a new generation of gargoors with a rebar body covered with net are used in the waters of Bushehr. In this study, which was conducted from November to July 1400 in the waters of Bushehr, totally, in 310 cruises in 30 coordinates, by 9 vessels, 90 gargoors made of rebar were surveyed. All of them were baited with wolf herring and catfish. 24 species from 12 families were identified. The most observed species was Orange-spotted grouper (Epinephelus coioides). The results showed that all the gargoors made of rebar, if they are not lost, return to the land after the end of fishing. The main reasons for getting lost were theft, trawling, and bottom gillnets, respectively. Also, to confirm the sampling results, 40 questionnaires were distributed among the fishermen. According to the results, rebar gargoors are preferred over wire gargoors in terms of life, strength, economic efficiency and lower amount of ALDFG. It is recommended that researchers combine their knowledge with the experiences of fishermen to design gargoors with fewer disadvantages while maintaining the merits of different gargoor models, especially from the economic and environmental point of view.

This study was conducted to survey of distribution and abundance of cutlassfish (Trichiurus lepturus, Linnaeus 1758) as target species between the fishing grounds of Bushehr and Hormozgan provinces. Sampling operations were carried out during the summer season in Bushehr province and autumn season in Hormozgan province in 2013. The fishing operation was done using commercial trawler vessel with a length of 27 m, the width of 7.2 m during 73 times net hauling in the fishing seasons. The used net in this research was a mid-water trawl net with a polyethylene yarn and mesh size of 75 mm (stretched) in the codend. The highest length frequency of cutlassfish was observed in the length range of 84-92 cm and the least length frequency was in the length range of 28-36 cm. The biomass and mean CPUA in Bushehr were 17169.55 tons and 8624.42 ± 1076.58 (kg nm-2) and in Hormozgan were 7425.804 tons and 8105.74 ± 1529.87 (kg nm-2), respectively. Also based on depicted maps by GIS software and CPUA index, Most densities of trapped cutlassfish in Hormozgan fishing grounds were around Hengam and Greater Tomb islands, and in Bushehr (Motaf area), there was a horizontal distribution in the western waters of this province.

Appendicularians are the most important group among zooplankton communities, widely distributed in all the oceans and they are considered as one of the most important sources of productivity and food supplies for secondary consumers. So this study aimed to identify, introduce and assess the temporal and spatial variations of the Appendicularians in the Persian Gulf, restricted to coastal waters of northern part of Bushehr. Appendicularians were collected during seven sampling programs, from Frake river-estuary, three sites of large creek-estuary of the Shif, one site in the sea, and one site in the Lashkari creek-estuary, at middle and last day of each season, midsummer of 2016 to spring of 2017. During all surveys, depth of the sampling location, Secchi depth, water temperature, pH, and salinity were measured. Finally, 4 species were identified, Oikopleura dioica, Oikopleura longicauda Appendicularia sicula and Fritillaria sp. The highest total density was observed in the sea station at March, with dominance of O. dioica and a relative abundance of 80%, relative abundance of O. longicauda, A. sicula and Fritillaria sp. were calculated 18.9%, 1.06% and 0.04% respectively, so Fritillaria sp were introduced as rare species. Two species of O. dioica and O. longicauda demonstrated completely different spatial and temporal distribution pattern, and based on dbRDA (distance based Redundancy Analysis), transparency explains effectively the distribution pattern of O. longicauda, and also depth and salinity are the most important factors which explain the distribution pattern of O. dioica and temperature was correlated factor with abundances of A. sicula, in our study area.

Site selection is a key factor in any aquaculture operation which makes land use sustainable. This study was conducted to identify the appropriate sites for development of shrimp culture in the southern cost of Bushehr Province using geographical information systems (GIS) and Multi Criteria Evaluation (MCE) by creating a database of information layers, criterias and effective alternatives including pond construction (slope, elevation, land use types and soil thickness), soil quality (type, texture and pH of soil), sea water availability (distance to sea and type of water source), and social and economic infrastructure (population density and distance to roads, local markets, and hatcheries) were obtained from the Landsat 8 satellite images and processed in GIS environment. The constraint layer was excluded from the areas that were not allowed to implement shrimp farming. An Analytical hierarchy model was developed to identify and prioritize the most suitable areas for shrimp farming. The Landsat images and 13 thematic layers were analyzed using ENVI and GIS. By consolidating and overlaying the data layers, the final map of the appropriate places for shrimp farming was prepared and classified the area of study in four various zones (most suitable, suitable, moderately suitable and not suitable). The study revealed that 18781 ha (16%) was categorized in the most suitable group, 46899 ha (40%) was suitable, 47784 ha (40.7%) was moderately suitable and 3818 ha (3.3%) was not suitable. These results were consistent with field verification. The map accuracy was evaluated by the method of Relative Operating Characteristic (ROC). The result of ROC (0.749) indicated the validity of the presented model. The results of the present study can help to develope shrimp farms and increase diversity of the economic activities in the coastal zone.

Identification and distribution of edible and decoration shells were carried out in Bushehr shoreline areas (50˚ 38´ - 29˚ 27´ to 52˚ 41´ – 27˚ 17´) from September 2008 to July 2009. The objectives of this study were identification, distribution and stock abundance of edible and decoration shells and in Bushehr shorelines. Samples were obtained bimonthly or seasonally from Ganaveh to Nayband at low tide. Some transects were selected and in each transects two sampling quadrat (0.25 m2) was placed at random. In one location Derage was used. Specimens were identified and numbered and the percentage of samples was used to show the distribution of the species in different areas. Faunal affinity between stations was calculated by Sorensen formula. In the studied area a total of 45 species or species groups were identified. The main area distribution for live edible bivalve, Solen brevis was located sat Bopatil, Gassir, Kaloo, Piazi and Bordekhoon. Other bivalve, Paphia cor that was sampled alive was distributed in the Gassir and also empty bivalve shell (90%) was seen in the Bordekhoon shoreline. Also the most important areas for the decoration shells were located in the Golestan and Nayband that 74% of these species were included of olive shells. In Golestan 50% of the shells was Callista spp. The empty bivalve shells, Trachycardium lacunosum were distributed in Lavar shoreline. The other species or species groups were distributed in the shoreline of the study areas in different months with the low abundance.