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Meteorological patterns, technical validation, and chemical comparison of atmospheric dust depositions and bulk sand in the Arabian Gulf region
2021
Elsayed, Yehya | Kanan, Sofian | Farhat, Ahmad
This study reports seasonal variations of meteorological parameters, atmospheric dust and dust-borne heavy metals concentrations measured, over a period of two years, next to two major airports (Dubai International Airport and Abu Dhabi International Airport) in the Gulf Cooperation Council (GCC) region. On-line monitoring stations were installed at each location next to dust samplers used to frequently collect PM2.5 and PM10 on Teflon filters for metal analysis. Clear seasonal variation in meteorological parameters were identified. The particulate matter concentrations depicted from the two locations were continuously monitored. The PM2.5 concentration ranged from 50 to 100 μg/m³ on normal days but reached 350–400 μg/m³ per day during mild storms. The PM10 levels ranged between 100 and 250 μg/m³ during normal days and spiked to 750 μg/m³ during mild storms. Energy Dispersive X-Ray Analysis (EDS) revealed the presence of significant amounts of alkali and alkaline earth metals, which pose potential harm to aircraft engines. ICP analysis showed the presence of heavy and toxic metals in concentrations that may pose harm to human health. Bulk sand samples from Abu Dhabi sites showed chemical similarities to the atmospheric dust samples. The concentrations of heavy metals, PM2.5, and PM10 are at levels that require further monitoring due to their impact on human health. The two years meteorological monitoring, with the seasonal variations, provided additional regional data in the Arabian Gulf. Furthermore, the study concluded that Sand and Dust storms (SDS) occur more frequently at the northern Arabian Gulf compared to its southern region. The chemical correlation between atmospheric dust and regional desert sand suggests the localized origin of the smaller dust particles that may form by breaking apart of the ground sand grains. As a result of the ongoing urbanization in the region, it is essential to collect additional data from various locations for a longer period of time.
اظهر المزيد [+] اقل [-]Synthesis and evaluation of coastal and marine biodiversity spatial information in the United Arab Emirates for ecosystem-based management
2021
Mateos-Molina, D. | Ben Lamine, E. | Antonopoulou, M. | Burt, J.A. | Das, H.S. | Javed, S. | Judas, J. | Khan, S.B. | Muzaffar, S.B. | Pilcher, N. | Rodriguez-Zarate, C.J. | Taylor, O.J.S. | Giakoumi, S.
The United Arab Emirates (UAE) host valuable coastal and marine biodiversity that is subjected to multiple pressures under extreme conditions. To mitigate impacts on marine ecosystems, the UAE protects almost 12% of its Exclusive Economic Zone. This study mapped and validated the distribution of key coastal and marine habitats, species and critical areas for their life cycle in the Gulf area of the UAE. We identified gaps in the current protection of these ecological features and assessed the quality of the data used. The overall dataset showed good data quality, but deficiencies in information for the coastline of the north-western emirates. The existing protected areas are inadequate to safeguard key ecological features such as mangroves and coastal lagoons. This study offers a solid basis to understand the spatial distribution and protection of marine biodiversity in the UAE. This information should be considered for implementing effective conservation planning and ecosystem-based management.
اظهر المزيد [+] اقل [-]Enhancing growth of mangrove seedlings in the environmentally extreme Arabian Gulf using treated sewage sludge
2021
Erftemeijer, Paul L.A. | Cambridge, Marion L. | Price, Brae A. | Ito, Satoshi | Yamamoto, Hiroshi | Agastian, Titus | Burt, John A.
The response of mangrove (Avicennia marina) seedlings to treated (wet) sludge from a sewage treatment plant (STP) was tested in a randomized block design experiment at a tree nursery on Mubarraz Island in the Arabian Gulf. The growth response of seedlings to half-strength and full-strength STP sludge was monitored over 103 days and compared with the response to freshwater, seawater and half-strength seawater treatments. Sludge treatments resulted in significantly greater plant growth, leaf number, leaf biomass and root biomass than the other treatments did. The positive effect of STP sludge on seedling growth is attributed to enhanced levels of total nitrogen (8.9 ± 0.1 mg l⁻¹) and total phosphorus (7.8 ± 0.2 mg l⁻¹) in the sludge and its low salinity. These results suggest that sludge from sewage treatment plants may be beneficially used in mangrove nurseries and plantations in this arid region, where soils are nutrient-poor and fresh water is scarce.
اظهر المزيد [+] اقل [-]Is the development of desalination compatible with sustainable development of the Arabian Gulf?
2021
Le Quesne, W.J.F. | Fernand, L. | Ali, T.S. | Andres, O. | Antonpoulou, M. | Burt, J.A. | Dougherty, W.W. | Edson, P.J. | El Kharraz, J. | Glavan, J. | Mamiit, R.J. | Reid, K.D. | Sajwani, A. | Sheahan, D.
The development of desalination has been essential to the rapid economic development of the countries bordering the Arabian Gulf. The current production capacity of sea water desalination plants drawing water from Gulf is over 20 million m³ day⁻¹, which may rise to 80 million m³ day⁻¹ by 2050. Whilst supporting aspects of sustainable development related to water and sanitation, desalination impacts the marine environment through impingement and entrainment of organisms in intakes, and through thermal, brine and chemical discharges. This may compromise other objectives for sustainable development related to sustainable use of the oceans. Under business as usual scenarios, by 2050, the impact of individual desalination plants will combine causing a regional scale impact. Without mitigating actions to avoid the business as usual scenario, by 2050, desalination in combination with climate change, will elevate coastal water temperatures across more than 50% of the Gulf by at least 3 °C, and a volume of water equivalent to more than a third of the total volume of water between 0 and 10 m deep will pass through desalination plants each year. This will adversely impact the coastal ecosystem of the Gulf, with impacts on biodiversity, fisheries and coastal communities and may cause potential loss of species and habitats from the Gulf. Given the significant implications of these preliminary findings, and in light of the precautionary approach to management, it is recommended that mitigating options addressing behavioural, regulatory and technological change are rapidly evaluated and implemented to avoid the development of desalination in the region along a business as usual pathway, and multidisciplinary research studies should be conducted to reduce uncertainty in predictions of future impacts.
اظهر المزيد [+] اقل [-]Bioaccumulation of heavy metals in tissues of Indian anchovy (Stolephorus indicus) from the UAE coast, Arabian Gulf
2020
Alizada, Nuray | Malik, Shaima | Muzaffar, Sabir Bin
Pollution in the Arabian Gulf has risen in recent decades due to rapid development in the region. We studied 21 elements in the liver, gastrointestinal (GI) tract and muscles of the Indian anchovy (Stolephorus indicus) to characterize bioaccumulation in this abundant forage fish. Mean concentrations (μg/g wet weight) of elements ranged as follows: Cd: 0.1–8.0; Cr: 0.1–24.0; Cu: 1.2–24.0; Ni: 0.3–76.5; Ca: 1237.0–15,270.0; S: 2966.0–7467.0; Zn: 7.1–247.0; V: 0.1–27.0; Hg: 0.04–0.18 and Sr: 8.1–191.0. Zn, Cu, Cr, and Cd in the tissues exceeded the maximum permissible limit recommended by FAO, WHO and EC. We suggest that bioaccumulation in fish could be a hazard for human consumption. Therefore, further monitoring is needed to better characterize pollutant levels in fish of higher trophic levels in the Arabian Gulf.
اظهر المزيد [+] اقل [-]Baseline survey of marine sediments collected from the Kingdom of Bahrain: PAHs, PCBs, organochlorine pesticides, perfluoroalkyl substances, dioxins, brominated flame retardants and metal contamination
2020
Bersuder, P. | Smith, A.J. | Hynes, C. | Warford, L. | Barber, J.L. | Losada, S. | Limpenny, C. | Khamis, A.S. | Abdulla, K.H. | Le Quesne, W.J.F. | Lyons, B.P.
A baseline survey of sediment contamination was undertaken at 14 locations around the coastline of Bahrain in May 2017, followed by a focused survey of 20 sites, in November 2019. Samples were assessed for industrial pollutants, including metals, PAHs and a suite of organohalogen compounds. The data generated indicated that levels of chemical contaminants were generally low and did not pose a toxicological risk when assessed against commonly applied sediment quality guidelines (SQG). The highest concentrations of PAHs and PCBs were identified in samples collected at coastal sites adjacent to a refinery area known to contain a diverse mix of industry. Tubli Bay, a heavily stressed small bay receiving high loads of sewage effluent, was also identified as an area warranting further investigation with elevated concentrations of BDE209, PFOS and metal contamination. Such data provides a useful baseline assessment of sediment contamination, against which management control measures can be assessed.
اظهر المزيد [+] اقل [-]Distribution and metal contamination in the coastal sediments of Dammam Al-Jubail area, Arabian Gulf, Saudi Arabia
2018
El-Sorogy, Abdelbaset | Al-Kahtany, Khaled | Youssef, Mohamed | Al-Kahtany, Fahd | Al-Malky, Mazen
Present work aims to document the distribution and metal contamination in the coastal sediments of the Dammam Al-Jubail area, Saudi Arabian Gulf. Twenty-six samples were collected for Al, V, Cr, Mn, Cu, Zn, Cd, Pb, Hg, Sr, As, Fe, Co and Ni analysis. Results of enrichment factor indicated that Sr, Cd, Cu, Hg, V, As, Ni, Cr and Zn gave enrichment factors higher than 2 (98.87, 40.28, 33.20, 27.87, 26.11, 14.10, 6.15, 3.72 and 2.62 respectively) implying anthropogenic sources, while Pb, Mn and Al have very low background level (1.37, 0.71, 0.124 respectively), probably originated from natural sources. Average concentrations of Sr, V, Hg, Cd and As were mostly higher than those from the background shale and the earth crust, the Caspian Sea, the Mediterranean Sea, the sediment quality guidelines, the Red Sea, the Gulf of Aqaba and the Gulf of Oman. The higher levels of the studied metals are mostly related samples with high Al and TOM content, as well as the visible anthropogenic pollutants along the studied coastline. The most recorded anthropogenic pollutants were sewage effluent, landfilling due to coastal infrastructure development, oil spills, petrochemical industries and desalination plants in Al-Jubail industrial city.
اظهر المزيد [+] اقل [-]Is reduced freshwater flow in Tigris-Euphrates rivers driving fish recruitment changes in the Northwestern Arabian Gulf?
2018
Ben-Hasan, A. | Walters, C. | Christensen, V. | Al-Husaini, M. | Al-Foudari, H.
Like fishing, natural regime shifts and human-induced environmental changes are often equally important factors in driving fish stock declines. In the Northwestern Arabian Gulf, many fish stocks are declining, raising questions about the reduction in the flow of Tigris-Euphrates rivers. Here we investigate the relationship between Tigris-Euphrates river flow and the estimated recruitment patterns from assessment models. We found a positive correlation between the estimated finfish recruitment trends and the flow of Tigris-Euphrates rivers. Additionally, the assessment model showed remarkably weak compensation ratio, likely indicating a reduction in the productivity of nursery area of two finfish stocks but not in that of the crustacean stock. Our investigation would be very critical in providing guidelines to the government agencies in the Northwestern Arabian Gulf as well as countries of Tigris-Euphrates basins: to consider the impacts associated with reductions in Tigris-Euphrates river flows on the ecosystem services of the region.
اظهر المزيد [+] اقل [-]Characteristics and sources of anthropogenic and biogenic hydrocarbons in sediments from the coast of Qatar
2017
Rushdi, Ahmed I. | Al-Shaikh, Ismail | El-Mubarak, Aarif H. | Alnaimi, Hajer A.J.A. | Al-Shamary, Noora | Hassan, Hassan M. | Assali, Mazen Abou
Surface sediment samples from the coastal zone of Qatar were collected and analyzed to determine the characteristics, and sources of anthropogenic and biogenic hydrocarbons. The main compounds in these surface sediments included n-alkanes, methyl n-alkanoates, diterpenoids, hopanes, steranes, phthalate esters, polycyclic aromatic hydrocarbons (PAHs) and unresolved complex mixture (UCM). Their total concentrations ranged from 18.7±3.7–81.1±7.5ng/g (3.7±0.6–10.4±4.8%) for n-alkanes, 8.3±2.3–51±3.4ng/g (3.0±2.0–5.6±2.0%) for methyl n-alkanoates, 1.8±0.1–10.5±1.0ng/g (1.0±0.5–0.4±0.1%) for diterpenoids, 0.0–79.3±7.4ng/g (0.0–7.9±0.6%) for hopanes, 0.0–32.9±7.9ng/g (0.0–6.5±1.0%) for steranes, 0.7±0.1–36.3±3.4ng/g (0.1±0.1–1.9±3.4%) for phthalates, 0.30±0.2–7.8±0.7ng/g (0.02±0.04–0.42±0.72%) for PAHs, and 38±9–609±57ng/g (38.5±13.4–56.5±13.4%) for UCM. The major sources of these lipids were anthropogenic petroleum residues and plasticizers (80–89%), with lesser amounts from natural higher plants and microbial residues (11–20%). Petroleum residues and plasticizer inputs to the coastal sediments of Qatar likely affect the marine ecosystems and associated species groups as well as shallow coastal nursery and spawning areas.
اظهر المزيد [+] اقل [-]Residence and transport time scales associated with Shatt Al-Arab discharges under various hydrological conditions estimated using a numerical model
2017
Alosairi, Yousef | Pokavanich, Tanuspong
Over the last several decades, concerns in the Northwest Arabian Gulf have risen regarding water quality and ecological conditions, particularly near Kuwait. This interest is mainly attributed to the reduction of freshwater discharge and its associated constituents from the Shatt Al Arab as a result of human activities at diverse scales. From the hydrological perspective, the reduction has also resulted in alteration to the dynamic regime and related residence time and transport conditions. Using a previously well-validated three-dimensional numerical model of the Northern Arabian Gulf (NAG) (Alosairi and Pokavanich, 2017), the residence and transport conditions of numerical tracers have been assessed through a series of numerical tests. The results indicate that density-driven circulations have played a key role in reducing the residence time in the Northwest Gulf by approximately 15% to 20% compared to tidal forces only. The transport conditions correlated well with the Shatt Al Arab discharges, but they were only significant along the Kuwait coast due to counter-clockwise circulations and alongshore currents. Arrival times and mixing processes varied reasonably with the Shatt Al Arab discharges; the results exhibited the enhancement in mixing and transport with increases in discharge. Residence times in the NAG associated with Shatt Al Arab discharge displayed spatial variations, particularly in Kuwait Bay, where the residence time increased by 60days during low discharge compared to high discharge.
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