Issue 2

Nowadays, the increase in population and industrial growth that generates lot of waste products which creates disposal problems and severe environmental hazards. The cement industry is one of the important sectors which liberates greenhouse gas such as carbon dioxide. The consumption of waste products which eradicate the disposal issues and also it diminishes the emission of greenhouse gases to the environment. This is an important reason for the introduction of cement-free Geopolymer Concrete. This paper was invented to understand the suitability of Geopolymer Concrete cured at ambient temperature in the construction industry and the effect of molarity on strength properties. Totally, five types of Geopolymer Concrete mixes were prepared by altering the molarities of sodium hydroxide like 4M, 6M, 8M, 10M and 12M. The compressive strengths (1, 3, 7, 14 and 28 days), splitting tensile strengths (7, 14 and 28 days) and flexural strengths at 28 days were studied for aforesaid molarities. Generally, the rise in molarity increases the compressive strength. The ultimate strength was achieved up to 57.53MPa at 28 days for 8M Geopolymer Concrete. For the validation of compressive strength predicted by Destructive test (DT), the Non-Destructive tests (NDT) (Rebound Hammer and Ultrasonic pulse velocity) were carried out at resembled age of curing. Regression analysis is also done between compressive strength established by DT and NDT results. The arrived linear regression equations were well correlated with the experimental results and the co-efficient (R2) values varied from 0.8970-0.9967.

Many eutrophic lakes contain rapidly growing hydrophytes. Overgrown biomass is usually me-chanically harvested and thrown away, leading to resource waste and secondary environmental pollution. Microbial degradation is an economically and environmentally friendly approach for managing hydrophytic waste, fuelling the search for efficient biomass degraders. Here, we present isolation and characterization of Aspergillus sydowii WIU-01, a novel cellulolytic fungus. Strain WIU-01 was isolated from air. The degradation rate (29.75 vs. 21.95%) and endoglucanase activi-ty (0.31 vs. 0.16 U mL–1) of the fungus were higher in Canna indica (emergent plant) medium than in Hydrilla verticillata (submerged plant) medium, accordingly. Further, fungal endoglucanase ac-tivity was significantly positively correlated with the degradation rate, neutral detergent fiber con-tent, and acid detergent fiber content of hydrophyte powder. Fungal biomass was significantly negatively correlated with reducing sugar and cellulose content of hydrophyte medium, but was significantly positively correlated with hemicellulose, acid detergent lignin, and ash content of the medium. Collectively, these observations indicate that A. sydowii decomposes emergent and sub-merged plant mass without acid–base sample pretreatment, albeit its endoglucanase activity is rela-tively low. This highlights the role of cellulolytic microorganisms in the natural environment and the notion that the environment can be a source of cellulolytic microorganisms for potential envi-ronmentally friendly applications.

The aim of this paper is to estimate the amount of aeolian dust, deposited by dry and wet processes, that is deposited to the eleven marine regions of the Mediterranean-Black Sea Marine System (MBMS) and to compare it to the riverine influxes (i.e. suspended and dissolved sediment loads). This research is based on information for aeolian dust deposition at several coastal stations, around the MBMS, following an extended research of the available literature. For data elaboration, processing, and visualization a G.I.S. environment was utilized. The total annual amount of dust input for the whole system has been estimated to 59.9 × 106 tonnes, of which 57.2 × 106 tonnes are deposited in the Mediterranean Sea and only 2.7 ×106 tonnes in the Black Sea. The contribution of dust input (load), corresponding to 6.2% and 0.8% of the total amount of suspended and dissolved load, for the Mediterranean and Black Sea respectively, reveals the significant role of the aeolian dust inputs to the MBMS marine environment, in particular, at its southern Mediterranean domain.

Contamination in water bodies with antibiotics and resistance genes is becoming an increasing threat to global health. Overuse of antibiotics has become a serious ecological problem worldwide. There is growing concern that antibiotics are losing their effectiveness due to increased antibiotic resistance in bacteria. During the last twenty years, the consumption of antibiotics has increased rapidly, which has been cited as one of the world’s worst abusers of antibiotics. Several studies have been conducted to solve this issue. Developed countries have introduced several methods but constructed wetlands have been found low cost technology. Although constructed wetlands (CWs) offer a potential way to remove these antibiotics from water supplies, knowledge of their mechanisms is limited. In this review, we highlight important aspects of antibiotic pollution in waters, the removal efficiency of constructed wetlands for antibiotic removal and that antibiotic pollution affects many things which taken together poses several challenges for environmental scientists. It has been discovered that four main factors are affecting the performance of constructed wetlands used for the treatment of antibiotics in water supplies, the types configurations of constructed wetlands, hydraulic load rates, substrates, plants, and microorganisms. Further researches focusing on these factors are recommended to improve the removal efficiency of antibiotics in constructed wetlands. Outcomes of the study could help wastewater treatment plant engineers with providing reliable design data and outline a road map for future researches.