جستجوی مقالات مرتبط با کلیدواژه "ماکروبنتوز" در نشریات گروه "مهندسی دریا"

This study was carried out for determining beach seine effects on the macroinvertebrate communities in Shohadaye Anzali -Shirin Mahale andestuaries of Polrud River study areas. In order to survey the effects of beach seine, samplings were carried out in selected stations during the beach seine fishery season (October- March) and when no beach seine fishery was performed (June-September). Hence, four stations in Shohadaye Anzali - Shirin Mahale and three stations in Polrud River estuaries were chosen for sampling. Statistical analysis of data, normalization, correlation, mean comparison for different parameter used, was performed by applying Kolmogorov–Smirnov test (K–S test) and Pearson's Correlation Coefficient, respectively. One-way ANOVA for comparison of means of each parameter, between stations, was used. Classifications of homogeneity of the groups of different benthic organisms throughout the stations were analyzed by Tukey’s test. The results of this study showed that there were significant differences in frequency and biomass of the macroinvertebrate species, during the the beach seine fishery season and after the closing of beach seine fishery (p< 0.05). The results also showed that there were no significant differences in species diversity index (p > 0.05).

In this study, the distribution of macrobenthos in Boojagh Marine National Park (BMNP) was studied. Sampling was conducted in six transects, perpendicular to the beach, using a Van Veen grab sampler, with five replications. Samples were collected in five seasons (2015-2016). Each transect include three stations at depths of 1 meter, 5 meter and 10 meter. Washed and fixed samples were transferred to the laboratory, sorted and different groups of microbenthic taxons were identified. Mollusca with an average of 588 individuals per square meter, Malacostraca with 225, Polychaeta with 175, Hexanauplia with 109 and Clitellata with 98 individuals per square were identified. Depth profiles showed that the benthos are mostly distributed at 10 meter depth, followed by five and one meter depths. The densest season was at summer of 2015, with 356 individuals per square meter followed by summer of 2016, autumn and winter of 2015 and spring of 2016. Overall, the most macrobenthos distribution was in 10 meter depth. Macrobenthos density in the summer was more and in the spring was less than other seasons.

The present study was performance in the estuaries Soro, Abi and fishery of Bandar Abbas and sampling in the warm season (summer 1390), cold (winter 1390) and the 9 stations was conducted. Based on the results, a total of macro groups, the highest prevalence of polychaete worms (with 54.7 percent) was evaluated in Three regions studied, with matching results of biological indicator BOPA (Bentic Opportunistic Polychaete and Amphipoda) on the ratio of two groups of polychaete and amphipoda performed, value analysis BOPA Show that , Soro estuary pollution and environmental stress levels are weak, The highest index BOPA among all the estuaries, was calculated by 1.58 in Shilat estuary. This reflects poor conditions and bad ecological estuary.. And the minimum value of the index measure to 0.736 Abi estuary, which represents ecological situation is bad, but compared between the three estuaries studied the ecological situation showed. over all, and a based on the degree of pollution three estuaries of study In conditions of extreme stress and classification pollution affected by ecological and environmental unsuitable assessed.

Lake Gahar is located in southwest of Iran, in East Lorestan province and at 2350m above sea level. There is little information and few studies on limnology of this lake . This tectonic lake is known to have a unique macro- invertebrate fauna. In order to perform a complete research on the zoo-benthic community of the lake, the present study was conducted during a period of seven months from April 2011 to December 2011 with the exception of 5 months during very cold seasons when the lake was covered by ice. The benthic assemblage was sampled monthly from 3 sites in profundal zone. In total 6 genera and species and 5 families were found from which 1 species is unique in Iran. In this research, the dominant species of the lake are Quistadrilus multisetasus , Stylodrilus herngianusof class Oligochaets and Pisidium casertanum of class Bivalvia. Their abundance percentage determined in respect of total distribution were %69, %13 and %6, respectively. The maximum abundance of total population of macro- benthos in Gahar lake was 11617.78±4910.379 individual per square meter in May and the minimum was 1436.32±671/87 individual per square meter in April.

In present research biomass, frequency and distribution of macrobenthos in Gorgan Bay was studied in 8 stations in 4 seasons in 2009. Sampling was done by Van Ven Grab in 3 replicates in each station. Identified macrobenthos belonged to 13 families. The most abundant family was Ampharetidae (76%) compared to total population of macrobenthos. Balanidae (10%), Cardiidae (6%) and Nereidae (4%) had the next abundance. Maximum biomass of macrobebthos was observed in Cardiidae (45%), Balanidae (44.78%), Nereidae (5.8%) and Tubificidae (5.27%), respectively. The greatest frequency of macrobenthos was found in spring with 4110/m2 and the least was in winter with 29.25/m2. Maximum and minimum of biomass was observed in spring (33.568 g/m2) and winter (.080 g/m2) respectively.