• Energy Research
• natural sciences close
• 6. Clean water close
• EG close

As a consequence of global change processes, plants will increasingly be challenged by extreme climatic events, against a background of elevated atmospheric CO2. We analysed responses of Arabidopsis thaliana to periods of a combination of elevated heat and water deficit at ambient and elevated CO2 in order to gain mechanistic insights regarding changes in primary metabolism. Metabolic changes induced by extremes of climate are dynamic and specific to different classes of molecules. Concentrations of soluble sugars and amino acids increased transiently after short (4-d) exposure to heat and drought, and readjusted to control levels under prolonged (8-d) stress. In contrast, fatty acids showed persistent changes during the stress period. Elevated CO2 reduced the impact of stress on sugar and amino acid metabolism, but not on fatty acids. Integrating metabolite data with transcriptome results revealed that some of the metabolic changes were regulated at the transcriptional level. Multivariate analyses grouped metabolites on the basis of stress exposure time, indicating specificity in metabolic responses to short and prolonged stress. Taken together, the results indicate that dynamic metabolic reprograming plays an important role in plant acclimation to climatic extremes. The extent of such metabolic adjustments is less under high CO2, further pointing towards the role of high CO2 in stress mitigation.

The Nile Delta has been suffering from complex environmental hazards caused by climate change and human-induced evolvements, which have led to adverse impacts on national food security. An unfavourable nexus between solid waste management issues and extreme hydrological events is examined mainly through extensive field investigation and literature research, which is an emerging issue affecting food safety and security whilst still being overlooked so far. The findings not only reveal the significance of the emerging issue but also support our proposed recommendations in the policy/legislation and technology sphere. This interdisciplinary research employs a holistic lens that covers diverse perspectives, including systemic problems, wastewater treatment, and environmental neuroscience, to explore the relationship between food, climate change, water management, and waste pollution, and to achieve novel discoveries for the practical adaptations of Egypt’s challenges.

AbstractThis study examined the physical properties of agricultural drought (i.e., intensity, duration, and severity) in Hungary from 1961 to 2010 based on the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI). The study analyzed the interaction between drought and crop yield for maize and wheat using standardized yield residual series (SYRS), and the crop-drought resilient factor (CDRF). The results of both SPI and SPEI (-3, -6) showed that the western part of Hungary has significantly more prone to agricultural drought than the eastern part of the country. Drought frequency analysis reveals that the eastern, northern, and central parts of Hungary were the most affected regions. Drought analysis also showed that drought was particularly severe in Hungary during 1970–1973, 1990–1995, 2000–2003, and 2007. The yield of maize was more adversely affected than wheat especially in the western and southern regions of Hungary (1961–2010). In general, maize and wheat yields were severely non-resilient (CDRF < 0.8) in the central and western part of the country. The results suggest that drought events are a threat to the attainment of the second Sustainable Development Goals (SDG-2). Therefore, to ensure food security in Hungary and in other parts of the world, drought resistant crop varieties need to be developed to mitigate the adverse effects of climate change on agricultural production.

The adverse industrial activities discharged contaminated wastewater directly into the water bodies that contain toxic substances such as heavy metals. The contours use of marble industrial effluents may affect the fertility of soil and crop growth. The present study was conducted to investigate the toxic effects of marble industrial effluents (M.E) on Zea mays L under the exogenous application of citric acid (CA) with different combinations such as marble industrial effluent (0, 30%, 60%, 100%) diluted with distilled water and CA (10 mM). The results showed significant decrease in the growth of Zea mays with increasing concentration of marble industrial effluent. The maximum reduction in plant height, root length, number of leaves, leaf area and fresh and dry biomass was observed at the application of 100% M.E as compared to control. Similar to growth conditions the photosynthetic machinery and the activities of antioxidant enzymes (Superoxide dismutase (SOD), Peroxidases (POD), Catalases (CAT), Ascorbate peroxidase (APX)) was also decreased with increasing concentration of M.E. The application of CA significantly alleviated the M.E induced toxic effect on Zea mays and ameliorated the growth, biomass, photosynthesis and antioxidant enzymes activities by reducing the production of reactive oxygen species. The C.A application also enhanced the heavy metal content such as chromium (Cr), cadmium (Cd), Zinc (Zn) in different parts of Zea mays. The results concluded that the Zea mays tolerant varieties can be a potential candidate for the M.E irrigated soil and might be suitable for the phyto-extraction of Cr, Cd and Zn.

Due to the potential interest, bioelectrochemical responses of activated sludge using the three-electrode system are tested. From the cyclic voltammograms, the oxidation current output is increasing due to incubation time increase, whereas 5, 25 and 39.33 μA are obtained after 3, 72 and 96 h, respectively. Changing the working electrode from glassy carbon to carbon paste led to the increase in the electrochemical signal from 0.3 to be 3.72 μA. On the other hand, the use of the lipophilic redox mediator (2,6-dichlorophenolindophenol (DCIP)) amplified the oxidation current to reach 19.9 μA instead of 2.1 μA. Based on these findings, the mixed microbial community of the activated sludge is exploited as a catalyst for the bio-oxidation of the degradable organic substrates, while DCIP is used as a mobile electron carrier from the intracellular matrix of the metabolically active cells to the carbon paste electrode which served as the final electron acceptor. Therefore, the extracellular electron transfer from the formed active biofilm at the electrode surface is assisted by the existence of DCIP.

Miscanthus species originated in Asia and were imported into Europe and North America as ornamental plants. They are perennial rhizomatous grasses with lignified stems and present very high growth rates, even in more temperate maritime climates. This potentially abundant biomass offers benefits to many sectors and is used to an extent in energy generation applications, however, issues with regards to its physicochemical combustion characteristics currently hinder this uptake. In this work, a novel alternative application, namely its direct use of dry miscanthus (DM) plant as an adsorbent for heavy metals removal (HMR) from wastewaters, was investigated. The physical, chemical, and leaching properties of DM were analyzed using XRD, SBET, TGA, DSC, SEM‐EDX, elemental analysis, halogen, and ICP techniques. Subsequently, the HMR capacity of miscanthus was studied for lead, copper, and zinc from aqueous solutions. Results showed a high percentage removal of 66%, 83%, and 88%, respectively, with the majority being removed during the first hour of the test. Overall the results show that DM plant can be effectively utilized in wastewater treatment. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1058–1067, 2018

Over the decades, the Zabaleen, the traditional waste (garbage) collectors of Cairo, have created what is arguably one of the world’s most efficient and sustainable resource-recovery and waste-recycling systems. Yet the continuation of this intricate relationship between community, environment and livelihood is jeopardized by the official privatization of municipal solid waste (MSW) services through contracts with technology-intensive multinational corporations which threatens the sustainability of the garbage collectors’ communities by removing access to their chief economic asset, waste or garbage. The situation is exacerbated by an official policy of moving the Zabaleen and their MSW sorting, recovery, trading and recycling activities further out of the city, on the grounds that this will turn their neighbourhoods into cleaner and healthier living environments. The consumption of Cairo’s sites of MSW collection and sorting open new socio-political spaces for conflict between multi-national companies and the Zabaleen’s traditional system. This is further indicated in the way Cairo’s waste materials have been subjected to new claims and conflict, as they are seen as a ‘commodity’ by global capital entrepreneurs and multi-national corporations, and as a source of ‘livelihood’ by the disadvantaged and marginalised Zabaleen population.

Abstract There is a growing demand for exploiting cost-effective carbon sources for mixotrophic cultivation of microalgae. Fucoidan and alginate were extracted from the brown seaweed Cystoseira trinodis and were subjected to hydrolysis using H2O, HCl, or NaOH for the mixotrophic cultivation of Dunaliella salina. The algal biomass was enhanced to 0.46 g L−1 and biomass productivity reached 41.83 mg L−1 day−1 using alkali hydrolyzed alginate, which was ∼1.6-fold higher than the values under the photoautotrophic conditions. Lipid content was increased to 21.81% w/w using alkali hydrolyzed fucoidan which was 1.78-times higher than the control. Several biodiesel quality parameters were calculated and indicated that mixotrophic cultivation enhanced the biodiesel properties. The biochemical composition showed that amino acid and insoluble and soluble protein productivities were promoted 2-3-folds in relation to the control. Similarly, glycerol and soluble carbohydrate (starch) productivities were increased ∼ 1.4-times, while insoluble carbohydrate productivity was 3.3-times higher than the control. Principal component analysis demonstrated that the starch content of D. salina was reduced in compensatory of lipid accumulation. In addition, the algal growth behavior was statistically fitted using modified logistic model which indicated that lag-phase and maximum growth rate were 0.75–3.89 day and 0.019–0.066 day−1, respectively.