مجله علوم و فنون دریایی
سال هجدهم شماره 2 (تابستان 1398)

The deployment of value-added services can be very effective in achieving a vision in order to facilitate the strategic decisions of ports. This research is based on empirical studies with a critical and descriptive realistic approach using case studies from Iranian ports. It aims to explore the potential contribution of value added services in ports as a logistical strategy for increasing competition. The lack of research on the provision of value-added services in marine logistics and its potential, as a competitive advantage is analysed from the point of view of port users. The results indicate that value-added services that are easily accessible and presented, are the provision of transportation services, warehousing services, fresh water supply services, refrigerated services, and product assembly sites. Based on the assumptions made in this article, the provision of value-added services has contributed to attract and keep port users (customers), and the conclusion is made on the validity of this claim.

The coastline, as a border where the water flow is relatively impermeable, can change the flow pattern and therefore, the study of its hydrodynamic role is undeniable. in coastal engineering studies and even wet ecosystems even it is simple. In this study, using three-dimensional simulations in the numerical model environment of MIKE 3, the Danish Hydrodynamic Institute, two types of three dimensional simulations have been proposed using Navier Stokes equations to investigate the role of the coastline in rectangular and curved basins. In both simulations, it is assumed that the characteristics of Qeshm's tidal channel are scientifically established. This study clearly shows that the uniform velocity pattern in a rectangular basin changes with the curvature of coastline on the curved basin. The tightness in the curvature of the basin causes an increase in speed (about 0.05 m/s) in accordance with the principle of mass conservation. The opening after the turn of the basin causes a decrease of 0.1 m/s (0.4 m/s in the rectangular basin to 0.3 m/s in a curved basin, equivalent to 25% speed). Another point to consider is the role of water level changes. There is not much difference in the speed pattern between Higher High Water (HHW) and Lower Low Water (LLW) in Neap tide, but in the case of Spring tide where the water level is higher, the difference is 0.1 m/s in the rectangular basin and 0.2 m/s in the curved shape basin.

In general, fishing activities are considered as one of the most important environmental disturbances in increasing the vulnerability of the mangrove ecosystems due to their destructive effects on the process of sedimentation and wave currents, decreasing biodiversity, and introducing oil pollutants into these ecosystems. Therefore, investigating and mapping the intensity of fishing activities in mangrove habitats are of great needs in conducting the vulnerability assessment and providing managerial solutions and empowerment of these ecosystems to minimize and compensate the damages caused by environmental hazards. The aim of this study was to investigate, determine, and delineate and the intensity of fishing activities in the mangrove habitats of the Hormozgan province. To this end, the map of intensity of fishing activities was prepared in Khamir, Qeshm, Tiab, Sirik and Jask habitats through mapping the mangrove habitats, drawing 598 cell networks of 4 × 4 km in the coastal waters and the available geospatial data, and number of vessels in the fishing ports of the Hormozgan province. The results showed that in terms of the geographic distribution and the number of vessels in the fishing ports of the Hormozgan province, the intensity of the fishing activities in the mangrove habitats is ranked as follows: Khamir habitat> Qeshm habitat> Tiab habitat> Jask habitat> Sirik habitat. The results of this study can be used as a prerequisite for assessing the vulnerability of the mangroves of Iran.

In this research we investigated the effects of Lactobacillus delbrueckii during three life stages of Acipenser persicus (stage 1: from beginning of exogenous feeding, stage 2: fingerlings with initial body weight of 10 g and stage 3: juveniles with initial body weight of 144 g) on growth performance, feeding and survival. In stage one, Artemia nauplii were enriched with probiotics and used as food for Persian sturgeon larvae for 15 days. Shift from live food to dry feed was programmed in seven days followed by rearing until day 30 with dry feed. In stage two (for one month) and stage three (for two months) probiotics were added to dry feed and delivered to fish. At the end of the stage one values of total length, total weight, weight gain and specific growth rate (SGR) of fish fed non-enriched Artemia nauplii (treatment 3) were significantly more than rest of the treatments. Values of total length, total weight, weight gain and SGR of fish fed co-feeding regime (treatment 4) were significantly higher than rest of the treatments at the end of the stage one. Growth performance and survival of experimental fish showed no significant differences amongst the treatments in stage two. Values of total weight, weight gain, SGR and survival of fish fed probiotic supplemented diet were significantly higher than control group in the stage three. It is advised to feed the juvenile fish for at least two months with probiotic supplemented feed in order to improve the growth performance and survival.

Wind-induced waves due to their high energy are one of the most important hydrodynamic phenomena in the sea, which are of particular importance in marine engineering. Considering the importance of prediction of wind-induced waveforms, in this study, the efficiency of the third-wave waveguide model in wave prediction (WaveWatch-III) has been investigated and the results of this model have been compared with the wave height obtained from the SW module software MIKE Is. In other words, in this paper, the prediction of wave characteristics is provided by the WW3 and SW models. To better compare the results of these two models, the environment and wind speed are considered to be the same. The results show that the WW3 conforms well to the results of the SW model, which will decrease with increasing water depth and distance from the coast, so that in deep water (approximate depth of water 500 m) and at intervals Offshore (50 km off the coast), the SW model provides more and more conservative data for wave characteristics. Also, the results of this study showed that the WW3 model would take more time to reach a steady state.

Antioxidant used for chronic disease as treatment and for repalcing artificial antioxidant with natural antioxidant; To investigate antioxidant activity, we used marine actinomycetes as an important resources of bioactive compounds.. In this study, for phylogenetic analysis of 15 marine actinomycetes isolated from Deylam intertidal sediments, 16S rDNA sequences were used. In addition, the total phenolic content (TPC) was determined with the Folin-Ciocalteu’s reagent using gallic acid as a standard and the results were expressed as mM of gallic acid. Then, the antioxidant potential of the extracts was determined by analytical methods, ferric reducing antioxidants power (FRAP). The antioxidant potential of the crude extracts exhibited strong ferric reducing power activity at 517nm and the reducing power activity was strongly correlated with the total phenolics content of the isolates. Among the tested isolates, AHA1 (1419 µM) and AMJ1 (608.8 ) showed the hieghest and lowest total phenolic content, respectivly. Moreover AHA3 and AMJ5 (230.66 and 75.57µM) showed the highest and lowest reducing power, respectivly. These strains showed acceptable antioxidant activity and could be good candidates for more studies as nature resources of pharmaceutical antioxidant compound.