Aquaculture ecosystem assessment is a major key for successful aquaculture Planning. There are many aquaculture farms constructed in Egypt, but because of the non-sufficient studies about the environmental conditions of aquaculture ecosystem assessment, many projects achieved negative results and had low economical returns. The present study was conducted to evaluate the aquaculture ecosystem assessment of irrigation water of El-Mahmoudia Canal, Alexandria, Egypt. The result indicated that temperature (24.65±0.4°C), DO (5.38±0.20mg/l), COD (14.40±4.5mg/l) and BOD (2.86±0.20 mg/l) were in the optimum range for O. niloticus. Chlorophyll a, b and carotenoids were 10.449±0.953, 4.685±0.704 and 2.374±0.054 μg/g, respectively. The biochemical composition of plankton showed that protein, lipid and carbohydrate were 37.7±3.39 %, 16.33±0.85%, and 11.23±2.63%, respectively. Moreover, SFA, MUFA and PUFA were 70.29±4.07%, 11.172±0.132 %, and 18.55±0.525 % of total fatty acids, respectively. Zooplankton community showed that rotifers and copepods configured the main bulk of zooplankton community (95.9% to the total zooplankton community). These conditions are considered the ideal recommended conditions for cultivation of Oreochromis niloticus that started with 100,000 fingerlings (distributed as 4.76 fish/m 3 of earth pond) for six months with 82% survival rate with final yield of 21.3 ton/1.6 hectare.

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The methods of data collection, processing, and assessment of the quality of the results of a survey conducted at the Southern Ionian Sea off the Messinian Peninsula, Greece are presented. Data were collected by the GEBCO-Nippon Foundation Alumni Team, competing in the Shell Ocean Discovery XPRIZE, during the Final Round of the competition. Data acquisition was conducted by the means of unmanned vehicles only. The mapping system was composed of a single deep water AUV (Autonomous Underwater Vehicle), equipped with a high-resolution synthetic aperture sonar HISAS 1032 and multibeam echosounder EM 2040, partnered with a USV (Unmanned Surface Vessel). The USV provided positioning data as well as mapping the seafloor from the surface, using a hull-mounted multibeam echosounder EM 304. Bathymetry and imagery data were collected for 24 h and then processed for 48 h, with the extensive use of cloud technology and automatic data processing. Finally, all datasets were combined to generate a 5-m resolution bathymetric surface, as an example of the deep-water mapping capabilities of the unmanned vehicles' cooperation and their sensors' integration.The ocean floor is the most remote and difficult part of our planet, yet to be explored. Due to the extreme conditions facing exploration, the majority of the world's ocean floor is still unmapped [1,2]. Modern mapping techniques, based on the acoustic technology, allow us the possibility to collect bathymetric and water column data, but the survey process is slow and expensive. The majority of present-day surveying efforts go into the busier, shallow waters for the purpose of safety of navigation. While this represents an understandable and necessary approach, it results in the majority of the deep ocean still being unmapped. The overall shape of the global ocean floor is an estimation based on the satellite altimetry technique [3] and interpolation between sparse acoustic measurements.The American foundation XPRIZE announced in 2015 that the next award will go to those who come up with the solution for faster, detailed mapping of the ocean floor, without exposing humans to the harsh sea environment. That was the beginning of the Shell Ocean Discovery XPRIZE. To compete in the final round of the Shell Ocean Discovery XPRIZE, each team had to present the solution for collecting bathymetric data and imagery data and successfully complete Round 1 in 2017. During the second round a year later, the bathymetric data collection had to achieve depths of up to 4000 m, with a vertical resolution of 0.5 m and a horizontal resolution of 5 m. The imagery needed to include images presenting recognizable geological, biological, or archaeological features on the seabed. The solution had to be autonomous or remote controlled, but there must have been no human inside the survey area, and no physical link between the devices and the mission control location. The mapping system, with all its elements, had to fit into one standard 40-ft shipping container. The minimum coverage to be achieved during t...

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The Egyptian coast of Gulf of Aqaba, north of the Red Sea, suffers from severe destruction and deterioration in habitat and biodiversity due to anthropogenic activities and flooding. The present work aims to evaluate the impacts of different human activities and flooding on the biodiversity of macrobenthic invertebrates along the Egyptian coast of the Gulf of Aqaba. From January 2019 to December 2019, many field trips (12 trips) were conducted to survey macrobenthic invertebrate communities and monitor water quality at nine sites within three sectors along the study area. Each site was divided into four ecological zones and one of five categories, according to the main activities at each site. Furthermore, satellite data were used to monitor the progress of land use and turbidity in the study area. Therefore, the current study assesses the relationship between these factors and water quality and macrobenthic invertebrate distributions, similarity, diversity, dominance and abundance. The results revealed that 53 macrobenthic invertebrate species belonging to three phyla (Mollusca, Echinodermata and Annelida) and one subphylum (Crustacea) were recorded. The echinoderm Echinometra mathaei was the major eudominant species. The northern part of the Gulf was higher in abundance and diversity with low land use and lowest water turbidity, while the south part showed contrary findings. All statistical analysis confirmed that the dissolved oxygen concentration was considered the only limiting factor for the abundance and diversity of macrobenthic invertebrates. Also, the variation in activities at investigated sites affected the dominance state of species in each site. Moreover, GPS data confirmed that the tourism activity had the largest influence on marine ecosystems and biodiversity, followed by fishing and desalination practices. Otherwise, flooding has significant influence on marine habitats and creates a habitat in which other certain species can survive. In the absence of awareness, intervention and disregard for the effective coastal zone management concept, especially for the unique marine ecosystems such as the Gulf of Aqaba, the degradation of biodiversity will continue until extinction, and human life is rendered unsustainable.

The Egyptian coast of Aqaba Gulf, north of the Red Sea suffers from severe destruction and deterioration in habitat and biodiversity due to anthropogenic activities and flooding. The present work aims to evaluate the impacts of different human activities and flooding on the biodiversity of macro-benthos invertebrates along the Egyptian coast of the Aqaba Gulf. From January 2019 to December 2019, many field trips (12 trips) were conducted to survey macro-benthos-invertebrate communities and monitor water quality at nine sites within three sectors along the study area. Each site was divided into four ecological zones and one of five categories, according to the main activities at each site. Furthermore, satellite data were used to monitor the progress of land use, and turbidity in the study area. Therefore, the current study assessing the relationship between these factors and water quality and macro-benthos-invertebrates distributions, similarity, diversity, dominance and abundance. The results revealed that fifty-three macro-benthos-invertebrates species belonging to four phyla (Crustacea, Mollusca, Echinodermata and Annelida) were recorded. Echinometra mathaei was the major eudominant species. The northern part of the Gulf was higher abundance and diversity with low land use and lowest water turbidity, while the south part showed the contrary findings. All statics analysis confirmed that the dissolved oxygen concentration was considered the only limiting factor for the abundance and diversity of macro-benthos invertebrates. Also, the variation in activities at investigated sites affected the dominance state of species in each site. Moreover, GPS data confirmed that the tourism activity had the largest influence on marine ecosystems and biodiversity, followed by fishing and desalination practices. Otherwise, flooding has significant influence on marine habitats and creates a habitat in which other certain species can be survived. In the absence of awareness, intervention and disregard for the effective coastal zone management concept, especially for the unique marine ecosystems such as the Gulf of Aqaba, the degradation of biodiversity will continue until extinction, and human life is rendered unsustainable.

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The single-beam acoustic ground discrimination system, Quester Tangent Corporation (QTC View, Series V), was applied to survey the Western (WH) and Eastern (EH) Alexandria harbors during 2011 to identify, map and compare the acoustic diversity of seabed. The surveys were conducted using echo sounder with frequency 50 KHz. The gradients were analyzed. The majority of the survey was carried out in shallow water, with the exception of the navigation channel in WH. The acoustic data obtained at one frequency was, individually, submitted to stacking, and clustering with a final solution of five acoustic classes in the WH and six acoustic classes in the EH. The acoustic survey was complemented with sampling and diver surveys. Throughout the grain size analysis and diver survey, the acoustic classes coincide with the result of grain size analysis. Study areas contain pollutant as indicated by the chemical analyses and diver observations. Bathymetric maps established by acoustic survey clarify that bottom slopes in study areas gradually increase towards the center of the harbors and El-Boughaz opening. The study includes the hydrographic data (Temperature, pH, etc) and nutrient salts (ammonia, nitrite, nitrate, and phosphate). The nutrients were extensively supplied since a long time ago from the main station at Kayet Bay as well as subsidiary 11 outfalls. It receives an amount of about 80,000 m 3 /day of untreated sewage which affects the physical, and chemical characteristics of the EH water quality. High values of ammonia (3.6 µM), Nitrate (1.4 µM) and Nitrite (1.6 µM) were recorded for surface water in the EH. Phosphate showed narrow range of variation between surface and bottom water of EH and WH. The analyses in the WH give the maximum values for Ammonia 4.0 µM, Nitrate 1.6 µM, Nitrite 0.19 µM and Phosphate values ranged between 0.3 and 0.5 µM. Amr Z. Hamouda et al. 80The benefits of this research is to identify the presence of sunken antiquities in the EH which have been confirmed by divers photographs, having detailed bathymetric maps, and identify the sea bed characteristics for Alexandria harbors. It is necessary to followup the biological and chemical changes in surface and bottom waters to trace sources of pollution and take necessary actions to protect water resources.