Scarcity of water and the small area of the agricultural land are considered as the crucial environmental issues challenged the Arabian Gulf countries. In this study, experiments were conducted to identify the salt tolerance during the germination and the seedling stages of some native halophytes in the State of Qatar. Seeds of eight native species (Salsola setifera, Halopeplis perfoliata, Caroxylon imbricatum, Suaeda aegyptiaca, Acacia tortilis, Limonium axillare, Tetraena qatarensis and Aeluropus lagopoides) were investigated. Except for Tetraena qatarensis, Acacia tortilis and Suaeda aegyptiaca, all achieved ≥ 30% of seed germination at a concentration of 200 mM NaCl. Around 30% of Salsola setifera seeds were able to germinate in a salt concentration of 400 mM. Germination recovery of seeds that have been treated with 800 mM NaCl for 3 weeks was the greatest for Halopeplis perfoliata (94%) and the lowest for Aeluropus lagopoides (22%). Five halophytes were investigated for seedling growth under saline irrigation ranged from 0 to 600 mM NaCl. No significant differences obtained in growth biomass of seedlings of each of Caroxylon imbricatum, Suaeda aegyptiaca and Tetraena qatarensis between saline and non-saline treatments.

Background This paper aims to investigate the occurrence and removal characteristics of phthalate esters from bottled drinking water using silver modified roasted date pits. Three adsorbents, namely roasted date pits (RODP), silver-modified roasted date pits (S-RODP), and activated carbon (AC) were used to investigate their adsorption characterizations in removing dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP), di-2-ethylhexyl phthalate (DEHP), and di-n-octyl phthalate (DNOP) from the collected bottle water samples. Methods The occurrences of the phthalate esters in the collected bottled water samples were carried out at different temperatures (30, 50, and 60 °C), and analyzed using gas chromatography-mass spectrometry analysis - selected ion monitoring. Batch adsorption isotherms were used to study and establish the efficiency of such adsorbents in removing phthalate esters, in which they describe the adsorbent-adsorbate interaction systems. Adsorption efficiency of the various adsorbents was investigated by using different adsorbent masses (0.05 g, 0.10 g, and 0.15 g) and temperature (30 °C, 50 °C, and 60 °C). Different physical and chemical characterizations were studied using scanning electron microscopy (SEM), Fourier transform infrared (FTIR), Brunauer-Emmett-Teller (BET) surface area, pore radius, and pore volume. Results The results indicated that the most abundant phthalate esters were DMP followed by DEP under 30 °C; however, DNOP was not detected in any of the tested water samples, except for one sample under 30 °C with a concentration of 0.031 μg/mL. The obtained results showed that phthalate esters leaching to the bottled drinking water were affected by storage temperature. The phthalate esters levels were increased with increasing the temperature to 60 °C. It was concluded that the ability of S-RODP for the adsorption of phthalate esters was better than the removal percentage obtained by AC and RODP. The removal percentage was increased from 90 to 99% by increasing the temperature from 30 to 50 °C and then decreased to 92.3% at 60 °C. Conclusion RODP was successfully used as an effective adsorbent for phthalate esters removal from drinking water. However, S-RODP has the highest removal abilities than other adsorbents due to the newly formed functional groups on its surface.

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Scarcity of water and availability of land for agricultural production are the most environmental issues that facing the (GCC) countries and Qatar one of them. Qatar lies in region which characterized by having high evaporation rate and minimum rate of precipitation, so the salt built on the soil in relatively high concentration. The natural vegetation of Qatar is scarce, scattered and limited to certain areas. Halophytes could play a major role to minimize adverse environmental impacts, such as global warming and the enhancement of primary productivity. The present study is kind of the first in screening for local halophytes to quantify their level of tolerance to saline environment. The outcome of this research is expected to serve future research in investigating halophyte economical values and their utilization of the salt effected lands in coastal and in inland areas of Qatar. Seven treatment levels of different concentrations of NaCl including the control treatment (0, 50, 100, 200, 400, 600 and 800 mM NaCl) were used to evaluate both seed germination stage and seedling growth of selected Qatari halophytes. Eight halophyte species were selected for the seed germination experiment those are: Salsola setifera, Halopeplis perfoliata, Caroxylon imbricatum, Suaeda aegyptiaca, Acacia tortilis, Limonium axillare, Tetraena qatarensis and Aeluropus lagopoides. In general the seed germination experiments showed a decrease in the rate of germination as the salt concentration increased. Most of the studied species had a degree of germination up to 200 mM NaCl. The recovery of seeds subjected to high salt concentration have shown a rapid high percentage recovery up to 94% after being subjected to 600 mM NaCl for Halopeplis perfoliata. Five halophytes species were selected to be used for the seedling growth experiments. The two measured parameters used to evaluate the effect of salt concentrations on seedling growth are plant height and dry weight (biomass) for both above and belowground parts. The obtained results from all measured parameters showed no significant differences among seedlings of Caroxylon imbricatum, Suaeda aegyptiaca and Tetraena qatarensis. In respect to different salinity concentrations, Our results indicated that future utilizing of these plants for any commercial product will be valuable to secure drinking water and food in Qatar.