Qatar University Life Science Symposium 2016: Biodiversity, Sustainability and Climate Change, with Perspectives from Qatar

Casuarina equisetifolia L. is a widespread tree that has been known for its allelopathic potential causing biological inhibition on plant seed germination. Leaf extract of Casuarina equisetifolia L. was evaluated for its allelopathic influence on various plant crops. Laboratory and field experiments were conducted to study its allelopathic effects on seed germination and seedling growth. Various concentrations of leaf extract (0, 1.25%, 2.5 and 5%) were prepared and used while in the greenhouse experiment, leaf powder was mixed with soil at concentrations of (0, 15, 30 and 45 g/kg soil). Results revealed that leaf aqueous extract of Casuarina equisetifolia L affected significantly seed germination of all selected plant crops under laboratory condition. Highest inhibition was observed with 5% concentration compared to control that was treated with distilled water. In addition, it was that leaf extract of Casuarina had maximum inhibitory effect on roots growth compared to shoots of the studied seedling. Greenhouse experiment demonstrated that C. equisetifolia exhibited significant allelopathic activity on wheat germination but did not affect plant growth characteristics based on all treatments. However, Casuarina leaf extracts showed positive effect on Mustard germination and plant growth. The inhibitory substances present in Casuarina equisetifolia L leaves could be used as a potential environmental friendly herbicide. However, allelopathy is a complex process where further studies should be done in order to understand types of chemical molecules, mode of action of the Allelochemicals on physiology and biochemical process of weeds and crop plants. Attention and effort should be made more in allelopathy now a days because of environmental protection issues as well as the need of organic food so allelopathy will have great value in sustainable agriculture in future.

Waste audit has proved to be a valuable first step in development of a viable waste minimization and recycling program. Waste characterization has been successfully used at many educational institutions in the United States and elsewhere for advancing campus sustainability plan. As part of the requirements for the special topic course: “Solid and Hazardous Waste Management,” taught by the first author at the Department of Biological and Environmental Sciences, Qatar University, in Spring 2016, students conducted waste audit of selected buildings on the campus. The designated buildings were visited before performing the waste audit and a questionnaire was used to record vital information about each building. Using common materials along with a portable electronic balance, the students sorted the waste into various categories to determine relative amount of each type generated at a particular building. The audit was conducted twice at each of the four buildings to obtain an average value. While the waste stream at the four buildings consisted essentially of paper, plastics, metals, and food waste, it was found that the relative abundance of each of type of waste was a function of the purpose and use of the building. Details of the waste audit procedure, materials and methods, along with discussion of the results obtained are included in the presentation. Results of the waste audit should provide baseline data for developing a sound waste minimization and recycling program at Qatar University. This information, combined with assessment of energy and water use on the campus, would serve as major steps in reduction of greenhouse gases by preventing recyclables from ending up in landfills; saving natural resources by increased recycling; and conservation of energy and water resources. Recommendations are made for expanding waste audit to cover all buildings on the campus to obtain comprehensive data for advancing Qatar University's sustainability plan. We recommend that a concerted effort be initiated to encourage the campus community to sort paper, plastic, metal, and food waste before tossing them into the trash receptacles; avoid co-mingling the waste, and to practice energy and water conservation.

Microalgae are photosynthetic microorganisms that can grow in different environments (sea water, fresh water, waste water soil, rocks….) and under various conditions (Light, pH, temperature, salinity….). During their phases of growth, they produce a variety of metabolites such as lipids, proteins and carbohydrates in large amounts over a short period of time. These metabolites can be processed into both biofuels and other useful bioproducts. Microalgal lipids can be converted to biodiesel via process called transesterification. The use of biodiesel will decrease the emission of harmful gases, which can help in reducing the greenhouse effects and global warming. It is nontoxic, biodegradable and has the potential to replace the conventional diesel fuel. The isolation of autochthonous microalgae, with high lipid-contents and biomass productivities, is a crucial aspect of the development of commercial production of microalgae-based biodiesel as well as food security. This is especially important for deployments in climates such as are found in Qatar, a peninsula in the west Arabian Gulf, which is characterized by an extreme desert climate. 53 autochthonous strains of microalgae were isolated from various freshwater, marine and terrestrial environments in Qatar that led to the establishment of the Qatar University Culture Collection of Cyanobacteria and Microalgae (QUCCCM). Strains were identified via ribotyping and characterized in terms of growth rate and lipid production. The molecular identification of the isolated strains showed a biodiversity and 13 different known genera were identified. Among them, Chlorella is the most abundant freshwater known genus (22.64%), followed by Chlorocystis (13.21%). Growth rate study evidenced a thermo and halotolerant Nannochloris isolate QUCCCM31. The strain is able to tolerate 45°C and wide salinity range 35–100 ppt. Determination of lipid content and lipid profiling indicated the presence of promising strains for biodiesel production such as Nannochloris sp. (strain QUCCCM31) with a promising FAME profile for biodiesel production. This study proved a biodiversity inside the Qatar University Culture collection with strains having different applications such as Biofuel as an environmental friendly alternative to the fossil fuel, and/or source of food and feed.

FTIR smog chamber experiments were performed to investigate the atmospheric fate of E- and Z-CF3CH = CHCF3 (1,1,1,4,4,4-hexafluoro-2-butene). The experiments were performed to study reactions of E-CF3CH = CHCF3 or Z-CF3CH = CHCF3 with Cl atoms, OH radicals, and O3 in 700 Torr of N2/O2 diluents at 296 ± 2 K. The study determined the Cl atom, OH radical, and O3 kinetics and the mechanism of the atmospheric oxidation of E- and Z-CF3CH = CHCF3. The main atmospheric fate for both compounds is reaction with OH radicals. Atmospheric chemistry of the reaction of Z-CF3CH = CHCF3 with OH and OD radicals were investigated by Baasandorj et al. in 2011, no other previous studies are available. The results of the present study are compared to the findings of Baasandorj et al. assessing the atmospheric impact of E- and Z-CF3CH = CHCF3. Infrared spectra were recorded, and the atmospheric lifetimes, the radiative forcings and global warming potentials (GWP) of the two butenes were calculated. This study provides a comprehensive description of the atmospheric fate of E- and Z-CF3CH = CHCF3. We present here the first results on the atmospheric chemistry of E-CF3CH = CHCF3 and of the Cl- and O3-initiated chemistry of Z-CF3CH = CHCF3.