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Emissions and Fuel Life Cycle Assessment of Non-passenger Diesel Vehicles in Qatar
2020
Al-Thani, H. | Al-Ghamdi, S. | Koc, M. | Isaifan, R. j.
The life cycle of diesel fuel in non-passenger vehicles was assessed for all registered vehicles in Qatar as of November 2017. The Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model was used as a source of normalized data to evaluate diesel fuel emissions for all non-passenger vehicle categories. This work aims at estimating the emissions from all non-passenger diesel vehicles in Qatar and evaluating the impact of the fuel life cycle assessment. The emissions of CO2, NOx, CO, SO2, VOC, black carbon (BC), organic carbon, fine particulates PM2.5, and coarse particulates PM10 were evaluated. SO2 emissions were found to be dominant during the well to pump (WTP) stage of the life cycle assessment (LCA) process, while the pump to wheel (PTW) stage was found to be dominated by CO, VOC, PM10, PM2.5, and BC emissions. NOx and organic carbon emissions were virtually the same during both stages. Total greenhouse gas emissions amounted to 5367 kt of CO2 equivalent (CO2-eq) in 2017 as compared with that in 2014 (5277 kt), the only reported value in Qatar for transportation emissions. In addition, several mitigation strategies are proposed to ensure sustainability in the transport sector and to minimize the negative impact of diesel fuel emissions in the country.
Afficher plus [+] Moins [-]Phytoremediation of polluted soils and waters by native Qatari plants: Future perspectives
2020
Al-Thani, R.F. | Yasseen, B.T.
Because pollution is predicted to worsen and sources of quality water for agriculture and other human activities are limited, many countries have been motivated to seek novel water sources. Qatar relies on groundwater and water desalinization to meet its water needs, and additional water resources will be needed to avoid unexpected crises in the future. Industrial wastewater (IWW) is an alternative water source, and much research activities should be focused on developing innovative and contemporary approaches to removing pollutants from IWW. Phytoremediation methods, shown to be efficient methods of removing and degrading contaminants of various kinds from polluted waters and soils, require knowledge of the native plants and associated microorganisms. In Qatar, many native plants (monocot and dicot, indigenous or introduced) have been shown to be greatly effective in remediating polluted areas. This article is a guide for Qatari scientists aiming to identify promising native plants and associated microbes for IWW phytoremediation. In it, we review the basic components of bioremediation and summarize the principle phytoremediation approaches and preferred recycling options. The multiple mechanisms and methods of phytoremediation for cleansing polluted soils and waters are also discussed as are details of the metabolic reactions degrading the organic components of oil and gas. Finally, heavy metal accumulation is addressed. Wastewater from industrial and domestic activities is currently being used to create green areas around Doha, Qatar, and such areas could be at risk of contamination. Many native Qatari plants and soil-dwelling microbes are efficient at removing organic and inorganic contaminants from polluted soils and waters, and some are promising candidates for achieving a clean environment free of contaminants.
Afficher plus [+] Moins [-]Epibenthic communities from offshore platforms in the Arabian Gulf are structured by platform age and depth
2021
Torquato, Felipe | Omerspahic, Mustafa H. | Range, Pedro | Bach, Steffen S. | Riera, Rodrigo | Ben-Hamadou, Radhouane
Oil and gas platforms act as artificial habitats for a myriad of marine organisms. In this study, we used opportunistic remotely operated vehicle (ROV) data to describe fouling assemblages through the characterization of functional groups in the Al Shaheen oil field, situated in Qatari waters. The surveys showed a strong vertical stratification, with the number of functional groups increasing from the surface to the bottom. In addition, the majority of functional groups had their highest frequency of occurrence in the 35–60 m interval. In turn, multivariate analyses showed a slight structure among platforms with different ages. The lowest number of functional groups occurred in the early ages (2–3 years old), and some groups either increased or decreased their frequency and abundance along the years. A step further is now required to determine whether these platform foundations should be converted to reefs after their decommissioning (i.e., Rigs to Reefs approach).
Afficher plus [+] Moins [-]A benthic habitat sensitivity analysis of Qatar's coastal zone
2021
Butler, Josh D. | Purkis, Lotte M. | Purkis, Sam J. | Yousif, Ruqaiya | Al-Shaikh, Ismail
Characterizing benthic habitat sensitivities of rapidly-developing countries is of paramount importance. Recent efforts defining the benthic habitat of Qatar's coastal zone with a high-resolution, ground-truthed benthic habitat map has provided a framework on which to develop a habitat sensitivity map. Here we present a sensitivity analysis catered towards identifying habitats with varying sensitivities to natural and anthropogenic stressors on a quantitative scale from 1 to 5, low to high. We have identified that the majority of the coastal area is low risk habitat (i.e. sandflats). However, there are six areas which are assigned as high risk by virtue of their rich occurrences of seagrass meadows, mangrove forests, and coral reefs - [1]. The reefs offshore of Al Zubarah on the west coast of the peninsula; [2] The Al Ruwais fringing reef on the northern tip of the peninsula; [3] The east-coast bays of Al Khor and Al Dhakira; [4] The shore-attached reef complex off Mesaieed (east coast); [5] The Jazirat al Bushayriyah offshore high; and, [6] The entire shelf of Halul Island. The sensitivity analysis presented here builds on a recently-developed benthic habitat map of Qatar's coastal zone and covers a total are of 4500km². Results gleaned from this analysis can be used to support marine spatial planning objectives and ecosystem-based management decision making.
Afficher plus [+] Moins [-]Baseline concentrations of mercury species within sediments from Qatar's coastal marine zone
2019
Ḥasan, Ḥasan | Elezz, Ahmed Abou | Abuasali, Mazen | AlSaadi, Hamood
Baseline concentration of total mercury (THg), organic extractable mercury and methylmercury (CH₃Hg) concentrations in sediments from the northeastern, eastern and southeastern parts of the Arabian Gulf were assessed. Surface sediments were collected from eleven stations from the coastal waters of Qatar. All analyses were performed on homogenised samples. Total mercury analysis was performed by Cold Vapour Atomic Absorption Spectrometry (CVAAS), and methylmercury was analysed by Cold Vapour Atomic Fluorescence spectrometry (CVAFS) after aqueous phase ethylation of the extracted samples. Total mercury (THg) in sediments varied from 8.0 μg/kg to 34.3 μg/kg. Methylmercury was detected in all stations and ranged from 1.46 μg/kg to 3.10 μg/kg accounting for 5.4% to 18.4% of total mercury. Total organic carbon (TOC) ranged from 0.16 to 0.72%, while Organic extractable mercury ranged from 1.55 μg/kg to 13.3 μg/kg. Analysis, the grain size within these sediments, was carried out previously paving the way for studying the influence of these parameters on the sedimentary mercury concentration. Speciation was also assessed, as were relations between the measured mercury fractions.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]Benthic surveys of the historic pearl oyster beds of Qatar reveal a dramatic ecological change
2016
Smyth, D. | Al-Maslamani, I. | Chatting, M. | Giraldes, B.
The study aimed to confirm the presence of historic oyster banks of Qatar and code the biotopes present. The research also collated historical records and scientific publications to create a timeline of fishery activity. The oyster banks where once an extremely productive economic resource however, intense overfishing, extreme environmental conditions and anthropogenic impacts caused a fishery collapse. The timeline highlighted the vulnerability of ecosystem engineering bivalves if overexploited. The current status of the oyster banks meant only one site could be described as oyster dominant. This was unexpected as the sites were located in areas which once supported a highly productive oyster fishery. The research revealed the devastating effect that anthropogenic impacts can have on a relatively robust marine habitat like an oyster bed and it is hoped these findings will act as a driver to investigate and map other vulnerable habitats within the region before they too become compromised.
Afficher plus [+] Moins [-]Seasonal and body size-dependent variability in the bioaccumulation of PAHs and their alkyl homologues in pearl oysters in the central Arabian Gulf
2022
Soliman, Yousria | Wade, Terry L. | Sericano, Jose L. | Al Ansari, Ibrahim
Spatiotemporal concentration patterns for 19 parents and their alkyl homologues were measured in Pinctada radiata from 7 locations in the central Arabian Gulf around Qatar in the winter, spring and summer (2014–2015). The concentrations of PAHs ranged from 20 to 2240 (262 ± 38.0 ng·g⁻¹ dw) with the highest occurrence in the Doha harbor (738.4 ± 197.3 ng·g⁻¹ dw) and the lowest in the west coast of Qatar (48.3 ± 5.8 ng·g⁻¹ dw). Residual PAHs in the oysters were about two times higher in winter than in spring and summer (P < 0.05). PAHs in oysters are dominated by 2 and 3 rings PAHs and their alkyls. Alkylated PAHs (APAHs) comprised >55 % of the ΣPAHs. Statistically significant differences in PAHs profiles among oysters were due in part to differences in lipid contents and shell biometrics. Principal component analysis (PCA) and diagnostic ratios for sources identifications suggested that PAHs accumulations in oysters were due to petrogenic and fuel combustion.
Afficher plus [+] Moins [-]Sources, spatial distribution and characteristics of marine litter along the west coast of Qatar
2020
Veerasingam, S. | Al-Khayat, Jassim A. | Aboobacker, V.M. | Hamza, Shafeeq | Vethamony, P.
The spatial distribution, sources and characteristics of marine litter (ML) from 36 locations spread over 12 beaches along the west coast of Qatar have been assessed. A total of 2376 ML items with varying sizes were found with an average abundance of 1.98 items/m². The order of abundance of ML along the coast was as follows: plastics (71.4%) > metal (9.3%) > glass (5.1%) > paper (4.4%) > fabric (4.0%) > rubber (3.9%) > processed wood (2.0%). Locations in the south and northwest coasts of Qatar had significantly higher concentrations of ML. Surprisingly, nearly 47% of the beached polyethylene terephthalate (PET) bottles were derived from the countries bordering the Arabian/Persian Gulf (Gulf), and most of them were produced in the last 2 years. The plastic materials were drifted by winds and currents to the Qatar coast. Gulf circulation provides evidence to the pathways of ML beached on the Qatar coast.
Afficher plus [+] Moins [-]A high-resolution remotely sensed benthic habitat map of the Qatari coastal zone
2020
Butler, Josh D. | Purkis, Sam J. | Yousif, Ruqaiya | Al-Shaikh, Ismail | Warren, Christopher
A comprehensive, high resolution, ground truthed benthic habitat map has been completed for Qatar's coastal zone and Halul Island. The objectives of this research were to; 1. Systematically compare and contrast pixel- and object-based classifiers for benthic mapping in a limited focus area and then to, 2. Apply these learnings to develop an accurate high resolution benthic habitat map for the entirety of the Qatari coastal zone. Results indicate object-based methods proved more efficient and accurate when compared to pixel based classifiers. The developed country-wide map covers 4500 km² and underscores the complex interplay of seagrass, macroalgal, and reefal habitats, as well as areas of expansive mangrove forests and microbial mats. The map developed here is a first of its kind in the region. Many potential applications exist for the datasets collected to provide fundamental information that can be used for ecosystem-based management decision making.
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