جستجوی مقالات مرتبط با کلیدواژه « ballast water » در نشریات گروه « شیلات »

In the present study, the ballast waters from 24 ships arriving at Shahid Rajaee Port in Bandar Abbas, Hormozgan Province, Iran, were studied in two warm and cold seasons (summer 2017 and winter 2018). The zooplankton sampling was conducted under the MEPC 173(58) method, by bucket and using a 50-micron mesh to filter 300 liters of ballast water. In total, 57 zooplankton species, belonging to 8 phyla, 11 classes, 15 orders, and 35 families were identified in the sampled ballast water, among which the Arthropoda phylum with 16 families and 23 species recorded the highest number of species  The highest and lowest density among the studied samples belonged to the Tintinnopsis gracilis species from the Codonellidae family (11.4%) and Calanopia elliptic species from the Pontellida family (0.04%), respectively. The results of the Pearson correlation test showed that there was a negative correlation between the measured pH parameter and the frequency of zooplankton (p<0.01). There was also a positive correlation between EC and Shannon diversity index (p<0.05). PCA test results showed that EC, temperature, salinity, and TDS factors had the most impact in stations with the highest number of species and abundance of zooplankton. The results of the cluster diagram showed the highest similarity between winter at the Western Indian Ocean (WW) and summer at the Western Indian Ocean (WS) at the level of 54%, and the lowest similarity between the winters at the Northwestern Indian Ocean (NW) at the level of 24% with other regions. All the studies species in the ballast waters of the Persian Gulf had been identified and reported by previous studies but certainly requires continuous monitoring management of the ballast water, and supervising their discharge into the marine environment.

The present study has been conducted to identify and enumerate ballast water phytoplankton on 24 ships entering Shahid Rajaee Port (13 bulk carriers, 4 oil tankers, 6 general cargo and 1 container), in two cold and warm seasons in winter 2017 and summer 2018, from the four origins as the name the Persian Gulf, western, eastern, and northwestern Indian Ocean.The sampling of phytoplankton was conducted by passing 100 liters of sampling waters through a 20-micron plankton net, in compliance with the G2 standard method approved by MEPC.173 (58). In this manner, 108 phytoplankton species were identified in the ballast water tanks of the sampled ships, belonging to 4 phylum, 5 classes, 23 orders, and 38 families. In the warm season, Dinophyceae (54%) and in the cold season, Bacillariophyceae (60.96%) were prevalent among the samples. The identified species from the Persian Gulf had the highest similarity with the species from the western Indian Ocean, and the least similarity with the eastern Indian Ocean. Apart from Odontella longicruris, all other species had been reported in the waters of the Persian Gulf in previous studies. This result shows that the phytoplankton assemblages between Shahid Rajaee Port and other parts of the Indian Ocean have a high similarity and does not impose a real threat to the environment from the ballast water transfer. However, from the identified species, 28 species (25.9%) are known to cause red tide and death of other aquatic species in the region, which highlights the importance of continuous monitoring and discharge control in the marine environment of the region.