32 research outputs found

    Plegadognathus bonariensis (Acari: Halacaridae): First halacarid mite report from Qatar

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    In this study, the genus Plegadognathus Morselli, 1981 with the species P. bonariensis. Viets, 1936) is recorded from Qatar for the first time. Diagnoses for the genus Plegadognathus and the short description of female of P. bonariensis are given with original illustrationsThis work has been conducted under the framework of the project NPRP7-1129-1-201, funded by the Qatar National Research Fund (a member of The Qatar Foundation)

    Plankton community and copepod production in a temperate coastal lagoon: what is changing in a short temporal scale?

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    Coastal lagoons are often exposed to intense short-term environmental changes and strong anthropogenic pressures influencing zooplanktonic communities and production. However, most works focus on long-term temporal scales using monthly or seasonal sampling strategies. The present study analysed the structure of the mesozooplanktonic assemblages, the production (egg production rates) and physiological condition (RNA:DNA ratio) of the copepod Acartia clausi in a temperate coastal lagoon (Ria Formosa) during the summer, using an intensive sampling approach. Salinity was the main factor affecting the short-term variability of mesozooplankton composition, followed by tidal phase (ebb tides) and semilunar cycle (spring tides). There was a positive relationship between the abundance of Appendicularia and the cladoceran Penilia avirostris with the toxic dinoflagellate Gymnodinium catenatum, suggesting no deleterious effects. The egg production rate of A. clausi was influenced by salinity and ammonia concentration, with a positive correlation between the egg productivity and the macronutrient, showing a possible adaptation of this calanoid species. The RNA:DNA index was positively related to egg production rate, suggesting that it is a good proxy for the reproductive output of copepods, even in short-term periods. This study shows that different timescales need to be included in regular monitoring of planktonic assemblages in coastal lagoons in order to understand the influence of environmental and anthropogenic variables on marine organisms.Investigador FCT Program: IF/01546/2015. European Regional Development Fund (COMPETE program- Operational Competitiveness Programme), and Portuguese national funds from FCT through projects MODELA (PTDC/MAR/098643/2008), UID/Multi/04326/2016, UID/Multi/04326/2019 and UID/MAR/04292/2013.info:eu-repo/semantics/publishedVersio

    Governing desalination, managing the brine: A review and systematization of regulatory and socio-technical issues

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    Desalination has become an attractive option for addressing water needs or solving problems of increasing water scarcity and short-term supply interruptions. However, several negative environmental impacts are associated with the resulting brine, for which a range of treatment, recovery, and disposal technologies have been suggested in the academic literature. Despite this, the technological emphasis fails to explain the absence of sustainable practices in many countries or the roles and responsibilities of involved actors. There is also a lack of consistent conceptualizations that include regulatory and governance-related issues. In this review paper, we examined the brine management issue in desalination activities as a socio-technical issue that needs to be embedded more strongly within governance and regulatory frameworks. Case experiences and options related to command and control, economic regulation, market-based approaches and public support are discussed and linked with brine management practices. This review paper shows that baseline regulations such as standards, assessments, and thresholds are still emerging, but they need to be complemented by approaches focusing on desalination costs and environmental performance. Overall, cross-sectoral collaboration in designing local brine regulation options is important for solving the brine issue. There is a need to create a joint action arena between the desalination industry, the public sector, and actors involved in innovations related to brine management. Besides, public leadership, through providing incentives and investments, is highly valuable for sustainable brine management. This leadership should address the cost of brine treatment or the required infrastructural development.This report was supported by the NPRP award [NPRP11S-0110- 180248] from the Qatar National Research Fund (a member of The Qatar Foundation)

    Evaluation of Roholtiella sp. Extract on Bell Pepper (Capsicum annuum L.) Yield and Quality in a Hydroponic Greenhouse System

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    This study was carried out to investigate the impacts of cyanobacteria (Roholtiella sp.) high-value product extract (HVPE) and water resuspended biomass WRB treatments on bell pepper production using the hydroponic system under greenhouse conditions. Six cyanobacteria treatments (6 ml L−1, 4 ml L−1, and 2 ml L−1 – HVPE, 6 ml L−1, 4 ml L−1, and 2 ml L−1 – WRB, and TR0 as control) were evaluated using the foliar application method. The results showed that foliar application of HVPE with treatments of 2 ml L−1, 4 ml L−1, and 6 ml L−1 produced significantly higher values of physical growth parameters of bell pepper (BP) plants (shoot length, the number of leaves, plant leaf length, plant leaf width, and the diameter of the shoot), SPAD index, yield components (the fruit length, fruit width, the number of fruit per plant, and fresh weight per fruit), biochemical composition [ascorbic acid, phenolic acid, and total soluble solids (TSS)], and the total yield compared to the control group TR0. Also, significant higher values of growth parameters (shoot length, the number of leaves, plant leaf length, plant leaf width, the diameter of the shoot), SPAD index, yield components (the fruit length, fruit width, the number of fruits per plant, and fresh weight per fruit), biochemical composition [ascorbic acid, phenolic acid, and total soluble solids (TSS)], and the total yield were obtained with foliar spraying WRB at 2 ml L−1, 4 ml L−1, and 6 ml L−1 compared to the control group TR0. Consequently, the treated bell pepper with Roholtiella sp. HVPE and WRB were more efficient in enhancing production and chemical constituents compared with the control group.This study was funded by the Graduate Student Grant (QUST-1-CAS-2020-10) provided by Qatar University, the NPRP8 project, and Qatar University IDC funds of RB-H

    Bioprospecting autochthonous marine microalgae strain from the Arabian Gulf Seawater, Kuwait for biofuel feedstocks

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    Bioprospecting programs are the key to increasing the current portfolio of indigenous microalgal strains accessible for different applications in microalgal biotechnology. In this work, nine fast-growing microalgal strains isolated from Kuwait's Arabian/Persian Gulf coastal waters were evaluated for their potential as biofuel feedstocks. 18S rRNA gene sequencing showed that the strains belong to five different genera: Chlorella, Nannochloris, Scenedesmus, Tetraselmis, and Nannochloropsis. In terms of the total lipid content, in comparison to the other strains, Tetraselmis sp. KUBS13G and Tetraselmis sp. KUBS16G displayed higher lipid contents of 29.56% dry weight (DW) and 26.13% DW, respectively, dominated by palmitic and oleic acids. Fuel properties calculated from the fatty acid methyl esters (FAMES) by empirical equations were compared with EN14214 (European) and ASTM D6751--02 (American) biodiesel standards. Multicriteria decision analysis (MCDA) methods, such as the Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) and Graphical Analysis for Interactive Assistance (GALA), were used to select suitable microalgae for biofuel feedstock based on their biodiesel fuel properties. Overall, the results suggested that the indigenous microalgal strain Tetraselmis, particularly Tetraselmis sp. KUBS37G, and Scenedesmus sp. KUB Sl7R are the most suitable strains for biofuel feedstock owing to their improved fuel properties, such as density (rho) (0.88 g cm-3), low kinematic viscosity (3.1 mm2 s-1), high cetane number (54 and 56, respectively), high oxidation stability (14.6 hr and 14.8 hr), and cold filter plugging point (1.0 degrees C and -6.1 degrees C).info:eu-repo/semantics/publishedVersio

    RNA:DNA ratios as a proxy of egg production rates of Acartia

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    Estimates of copepod secondary production are of great importance to infer the global organic matter fluxes in aquatic ecosystems and species-specific responses of zooplankton to hydrologic variability. However, there is still no routine method to determine copepods secondary production in order to eliminate time consuming experimental analyses. Therefore, we determined whether there is a correlation between Egg Production Rates (EPR) and RNA:DNA ratios of Acartia species, by measuring their seasonal and spatial variability and the influence of environmental factors for Acartia sp. collected in the Guadiana river estuary. EPR of Acartia tonsa was positively related with chlorophyll a concentration, freshwater inflow and biomass of dinoflagellates, while Acartia clausi was only related to dinoflagellates. Dinoflagellates seem to be the optimal food item influencing the reproduction of both Acartia species in the studied area. The biochemical index RNA:DNA was positively related to EPR, indicating that it is a good proxy of copepod production and a promising method to use in the future to estimate secondary production. (C) 2017 Elsevier Ltd. All rights reserved.Portuguese Foundation for Science and Technology (FCT) [SFRH/BD/28198/2006]FCT [SFRH/BSAB/113684/2015, SFRH/BPD/105419/2014, IF/01546/2015]FTC [UID/Multi/04326/2013]info:eu-repo/semantics/publishedVersio

    Investigation of Spatiotemporal Variability of Microplastics in Qatar's Cstal Environment

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    There has been a tremendous proliferation in plastic production in the last five decades due to its low cost and versatile applications. Plastic debris dominates the marine litter globally and has been found in the most pristine environment including the abysmal region of the world ocean. Studies show that over 8 million tons of plastics are dumped in the ocean annually (Gregory, 2009). Plastics are persistent in the environment and take several decades to degrade especially in the ocean. Large plastic debris can heavily damage the coral reefs and may cause entanglement, choking, blockage of digestive tracts when ingested by turtles, whales, sharks etc, causing several thousand deaths annually among these organisms. Microplastics are tiny plastic particles that seldom originate from fragmentation of large plastic debris or are produced to serve some specific purposes. Microplastics pose greater threats as they can be mistaken for food by filter-feeders and planktivorous fish, and can also adsorb large quantities of recalcitrant organic pollutants (OPs). Impacts on marine biota may include endocrine disruption, carcinogenesis, and sexual disruption, etc. These impacts may not always be obvious but OPs surely affect marine biota once they enter the food web even at low concentrations (Mato et al., 2001) which biomagnify up the marine food web, hence, explains the need for their investigation. In this study, the spatial and temporal distribution of microplastics was investigated for the first time in Qatar; both in sediments and seawater. Eight beaches across Qatar and four sea surface stations were surveyed between the months of December 2014 and March 2015. The objectives of this study were: 1.To analyze the spatial and temporal variability of microplastics in seawater and sediments, in sea surface and intertidal sandy beach environments, respectively. 2.To characterize the isolated microplastics based on size, shape, colour, and type of polymer. 3.To describe macroplastics collected from beaches based on polymer type and quantify the concentration of OPs adsorbed on their surfaces. 4.?To investigate the rate of adsorption of OPs on virgin plastic pellets in a field experiment. A general overview of the followed methodologies is given in Appendix 1. In the first phase of this study, the spatial and temporal distribution of microplastics was investigated in seawater and sediments respectively. Four sea surface stations (Appendix 2) and eight beaches (Appendix 3) across Qatar were surveyed between the months of December 2014 and March 2015. Seawater was sampled respectively with a surface neuston net (300 ?m mesh size) towed off the side of the speedboat in undisturbed water for 5 minutes at 1.5 knots (Doyle et al., 2011). Next, collected materials in the cod were transferred into labeled, acid-treated insulated glass containers to prevent contamination. Concentrations of microplastics were given in square meters as sampling was done in two-dimensional air-sea interface. Physicochemical parameters (temperature, salinity, pH and dissolved oxygen) were measured in-situ and recorded at each sampling site. Additionally, eight coastal stations (Al Dhakhira, Ras-Laffan, The Pearl, Doha Bay, Al Ruwais, Dukhan, Umm Bab, and Mesaieed) were chosen on the basis of their accessibility and being evenly distributed along Qatar coastline. For each sampling, sediments from the top 2 cm were collected at the most recent high tidal mark on shore from a square area (0.5 0.5 m) along the shore line. Three replicate quadrats (5 meters apart) were sampled in each beach. The samples were homogenized and transferred into acid-treated glass containers to prevent contamination and transported to the laboratory for analyses. Microplastics (Appendix 4) were discovered in all samples and their abundance varied both in intertidal sandy beaches and sea surface. Two-factor ANOVA revealed that the spatial variability of microplastics in sea surface stations was statistically significant however, there was no observable temporal variability (Appendix 5). The average concentration of microplastics in all 8 beaches was not significantly different (Appendix 6). Chemical analysis revealed the occurrence of OPs with endocrine effects on all obtained macroplastics, and concentration of pollutants was consistent in all sites. Large piece-to-piece variations of contamination up to two orders of magnitude were discovered within sites (2 to 1,005 ng/g), although there was no significant difference in contaminant concentration among all sites for PCBs and PAHs respectively. Since plastic debris are hydrophobic and easily adsorb organic pollutants the second phase of this study was targeted at investigating the concentration of PCBs and PAHs adsorbed on macroplastics in situ. Field adsorption/desorption experiment was performed to investigate how pellets of different polymers and contaminated with POPs behave when placed in ambient seawater. Pellets were deployed and later retrieved at 48h, 96 h, 192 h, and 312 h respectively. The pellets were analyzed for PCBs and PAHs and undeployed pellets were also analyzed at time 0. Adsorbed PCBs and PAHs concentration showed a steady decrease with time, suggesting that contaminated pellets ending in the marine environment release their adsorbed contaminants in less contaminated seawaters revealing a complex OPs dynamic between plastics an seawater as a function of differential concentrations of pollutants and environmental conditions. This study is the first of its kind in Qatar and seemingly in the entire Arabian Gulf region. Marine pollution is a growing concern in Qatar coastal and offshore environment. Marine debris is of major concern due to the fact that plastic can take several decades to be fully degraded. Results from this study indicate that microplastics are ubiquitous in Qatar coastal environment and the fact that they are easily mistaken for food and ingested by zooplankton and smaller fishes makes them a serious threat to the marine food web. Hence, regular monitoring of the occurrence of microplastics and studying how they may affect the foodweb and potential contaminations of exploited (seafood) species are needed to give policy makers an insight of the sources of the debris and proffer suggestions on how to tackle the menace using a holistic approach.Qscienc

    Uncovering responses of zooplankton community to CO2 acidification in Qatar coastal waters

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    The combustion of fossil fuels is pushing atmospheric concentrations of carbon dioxide (CO2) to unprecedented levels. This rapid increase in atmospheric CO2 is causing global changes, with noticeable increases in temperature, sea level rise and changes to marine carbon chemistry (i.e., Ocean Acidification - OA). The today average pH of ocean surface waters has already declined by 0.1 units from pre-industrial levels. According to the IPCC representative concentration pathways (RCPs), further declines in pH are predicted until the end of the century, varying between 0.14 units and 0.43 units. OA is irreversible on short time frames and previous studies have shown the potential impacts of ocean acidification on the physiology, reproduction, immunology and behavior of marine organisms, with effects already documented in multiple species and several regions of the world, although not in the Arabian Gulf. Nevertheless, the strong environmental variability of the Arabian Gulf presents good opportunities to study the potential impacts of future global change on marine ecosystems and to investigate the underlying mechanisms governing their resistance and adaptation to future environmental extremes. In this research we are targeting the response of zooplanktonic assemblages to OA, since these are commonly used as bioindicators of environmental and climate driven impact on marine ecosystems. The approach is mainly experimental, using controlled CO2 perturbation experiments, done aboard the Qatar University research vessel “Janan”. We are specifically investigating the response of zooplankton communities to relevant scenarios of seawater acidification by CO2, in terms of assemblage composition and structure; respiration rates; and egg production rates. The first round of experiments was conducted during a 3 day cruise offshore from Doha (June 3–5, 2016); complemented with a second cruise and round of experiments (November 17–19, 2016). Results provide insightful information about zooplankton communities’ responses to high CO2 levels in seawater of the Arabian Gulf and contribute to a better understanding about the biogeochemistry of coastal marine areas in Qatar, and more broadly in the Arabian Gulf.This study is funded by QNRF through the project “Zooplankton community responses to CO2 acidification in Qatar coastal waters (UREP18-177-1-021)

    Using vertebrate environmental DNA from seawater in biomonitoring of marine habitats

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    Conservation and management of marine biodiversity depends on biomonitoring of marine habitats, but current approaches are resource‐intensive and require different approaches for different organisms. Environmental DNA (eDNA) extracted from water samples is an efficient and versatile approach to detecting aquatic animals. In the ocean, eDNA composition reflects local fauna at fine spatial scales, but little is known about the effectiveness of eDNA‐based monitoring of marine communities at larger scales. We investigated the potential of eDNA to characterize and distinguish marine communities at large spatial scales by comparing vertebrate species composition among marine habitats in Qatar, the Arabian Gulf (also known as the Persian Gulf), based on eDNA metabarcoding of seawater samples. We conducted species accumulation analyses to estimate how much of the vertebrate diversity we detected. We obtained eDNA sequences from a diverse assemblage of marine vertebrates, spanning 191 taxa in 73 families. These included rare and endangered species and covered 36% of the bony fish genera previously recorded in the Gulf. Sites of similar habitat type were also similar in eDNA composition. The species accumulation analyses showed that the number of sample replicates was insufficient for some sampling sites but suggested that a few hundred eDNA samples could potentially capture >90% of the marine vertebrate diversity in the study area. Our results confirm that seawater samples contain habitat‐characteristic molecular signatures and that eDNA monitoring can efficiently cover vertebrate diversity at scales relevant to national and regional conservation and management.Maersk Oil; Qatar National Research Fund. Grant Number: NPRP 7 ‐ 1129 ‐ 1 – 201; Naturvidenskab og Teknologi, Aarhus Universite

    Novel composite materials of modified roasted date pits using ferrocyanides for the recovery of lithium ions from seawater reverse osmosis brine

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    In this paper, novel composite materials from modified roasted date pits using ferrocyanides were developed and investigated for the recovery of lithium ions (Li+) from seawater reverse osmosis (RO) brine. Two composite materials were prepared from roasted date pits (RDP) as supporting material, namely potassium copper hexacyanoferrate-date pits composite (RDP-FC-Cu), and potassium nickel hexacyanoferrate-date pits composite (RDP-FC-Ni). The physiochemical characterization of the RO brine revealed that it contained a variety of metals and salts such as strontium, zinc, lithium, and sodium chlorides. RDP-FC-Cu and RDP-FC-Ni exhibited enhanced chemical and physical characteristics than RDP. The optimum pH, which attained the highest adsorption removal (%) for all adsorbents, was at pH 6. In addition, the highest adsorption capacities for the adsorbents were observed at the initial lithium concentration of 100 mg/L. The BET surface area analysis confirmed the increase in the total surface area of the prepared composites from 2.518 m2/g for RDP to 4.758 m2/g for RDP-FC-Cu and 5.262 m2/g for RDP-FC-Ni. A strong sharp infrared peak appeared for the RDP-FC-Cu and RDP-FC-Ni at 2078 cm−1. This peak corresponds to the C≡N bond, which indicates the presence of potassium hexacyanoferrate, K4[Fe(CN)6]. The adsorption removal of lithium at a variety of pH ranges was the highest for RDP-FC-Cu followed by RDP-FC-Ni and RDP. The continuous increase in the adsorption capacity for lithium with increasing initial lithium concentrations was also observed. This could be mainly attributed to enhance and increased lithium mass transfer onto the available adsorption active sites on the adsorbents’ surface. The differences in the adsorption in terms of percent adsorption removal were clear and significant between the three adsorbents (P value < 0.05). All adsorbents in the study showed a high lithium desorption percentage as high as 99%. Both composites achieved full recoveries of lithium from the RO brine sample despite the presence of various other competing ions.This work was made possible by Qatar University collaborative internal grant # [QUCG-CAS-20/21-2]. The findings achieved herein are solely the responsibility of the author[s]
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