Geochemical fractionation and spectroscopic fingerprinting for evaluation of the environmental transformation of potentially toxic metal(oid)s in surface–subsurface soils

Environmental Geochemistry and Health - The contamination of soil by toxic metal(oid)s has emerged as a major concern worldwide, particularly in developing countries. A metals behavior in the soil...     

Habitat preference and population estimates of Indian pangolin (Manis crassicaudata) in district Chakwal of Potohar Plateau,Pakistan

Indian pangolin (Manis crassicaudata) is a fossorial, “Near threatened” mammalian species occurring in Pakistan and facing a risk of endangerment in its wild habitat. Being nocturnal, ecological data of the species is lacking in the country and in south Asia as well. The current study investigated some ecological parameters of the species like, distribution, habitat analysis, population and food habits in district Chakwal of Potohar Plateau. Illegal trapping and killing by professional nomads for its scales is the main threat to the species in the study area.     

Application of biochar in advanced oxidation processes: supportive,adsorptive, and catalytic role

Environmental Science and Pollution Research - The advanced oxidation processes (AOPs), especially sulphate radical (SO4•−)–based AOPs (SR-AOPs), have been considered more...     

Use of constructed wetland for the removal of heavy metals from industrial wastewater

This study was conducted to investigate the effectiveness of a continuous free surface flow wetland for removal of heavy metals from industrial wastewater, in Gadoon Amazai Industrial Estate (GAIE), Swabi, Pakistan. Industrial wastewater samples were collected from the in-let, out-let and all cells of the constructed wetland (CW) and analyzed for heavy metals such as lead (Pb), cadmium (Cd), iron (Fe), nickel (Ni), chromium (Cr) and copper (Cu) using standard methods. Similarly, samples of aquatic macrophytes and sediments were also analyzed for selected heavy metals. Results indicate that the removal efficiencies of the CW for Pb, Cd, Fe, Ni, Cr, and Cu were 50%, 91.9%, 74.1%, 40.9%, 89%, and 48.3%, respectively. Furthermore, the performance of the CW was efficient enough to remove the heavy metals, particularly Cd, Fe, and Cu, from the industrial wastewater fed to it. However, it is suggested that the metal removal efficiency of the CW can be further enhanced by using proper management of vegetation and area expansion of the present CW.     

Changes in water-extractability of soil inorganic phosphate induced by chloride and sulfate salts

GOAL, SCOPE AND BACKGROUND: One of the principal experimental variables which effect the results of phosphorus (P) sorption studies is the ionic composition, in addition to both species and concentrations of the contacting solution. In spite of the realization that ionic species, concentrations and their compositions effect P sorption and/or desorption, most of the salt-related studies are confined to Cl- (anion) in association with different cations. While the knowledge about the comparative response of P to Cl- and SO4(2-) ions was lacking, the current study was conducted to evaluate the comparative effects of anions (in association with cations) on inorganic P release and P fractions in the soil. METHODS: The test soil was amended with livestock compost manure (OP); KH2PO4 (IPk) or Ca(H2PO4)2 (IPc) at a rate of 1ppm. Soil was subjected to one salt and nine subsequent water extractions and different P fractions were measured. Four salt types, NaCl, Na2SO4, KCl and K2SO4, were used at levels of 0.5 M. RESULTS: Irrespective of P sources, P release was substantially increased in the salt-pretreated soil as compared to the non-saline soil. Sulfate salts released more P in subsequent water extractions than Cl-. Phosphorus release decreased for salt types with Na2SO4 > NaCl > K2SO4 > KCl and for P sources with OP approximately IPk > Control (without P application) > IPc, respectively. DISCUSSION: No previous study was found to compare the results of more P release by SO4(2-) than Cl- salt. Most of the previous studies focused on anion sorption capacities, but the mechanism for their adsorption is not fully known. Most of the authors suggested that the mechanisms of SO4(2-) and PO4(3-) adsorption are similar, and that both ions compete for the same sorption sites (Kamprath et al. 1956, Couto et al. 1979, Pasricha and Fox 1993). Although adsorbed SO4(2-) does not compete strongly with PO4(3-), there is likely to be some competition for sorption between these anions which may cause comparatively more P release by SO4(2-) than Cl- salts. Higher P release by Na-saturation could be due to the release of P associated with oxide surfaces or due to dissolution of Ca-P phases (Curtin et al. 1987). CONCLUSIONS: Study clearly showed that not only cations species differ for P desorption capacity, but associated anions also play a vital role in the fate of P under saline environments. Synergetic effects exist between Na and SO4(2-) ions which enhanced the P release. This study has also confirmed the fact that P from organic sources is available as well as from inorganic P sources. However, P release depends more on the type of P source applied than on total P. RECOMMENDATIONS AND PERSPECTIVES: It is highly recommended that more than one anion species must be used in the research plans for evaluating the P response in a saline environment. The results have important implications from the point of view of research, as most of the researchers focus on different cations only for evaluating P response to salts from an environmental point of view. However, our study has made it clear that anions in association with cations differed for their effects on P release.     

Exploring antibiotic resistance genes,mobile gene elements,and virulence gene factors in an urban freshwater samples using metagenomic analysis

Environmental Science and Pollution Research - Antibiotic resistance genes (ARGs) and antimicrobial resistance elements (AMR) are novel environmental contaminants that pose a significant risk to...     

Impregnation on activated carbon for removal of chemical warfare agents (CWAs) and radioactive content

Environmental Science and Pollution Research - Nuclear, biological, and chemical warfare (NBC) agents cause an inevitable threat to defense forces and civilians. Exposure to these toxic agents...     

Long-term gendered consequences of permanent disabilities caused by the 2005 Pakistan earthquake

This study documents the long-term gendered impact of the 2005 Pakistan earthquake on women and men who were rendered paraplegic as a result of spinal cord injuries sustained during the disaster. Coping mechanisms are also mapped. The findings show that three years after the disaster, paraplegic women are socially, emotionally, and financially isolated. The small stipend they receive is a significant source of income, but it has also led to marital distrust, violence, and abuse. In contrast, men receive full social and emotional support. Their key concern is that the government is not providing them with opportunities to be economically productive. Contemporary discourse and post-disaster policies, while acknowledging the importance of incorporating a gender perspective in the immediate post-disaster period, have failed to acknowledge and address the longer-term gendered impact of disasters, in terms of the different types of impact and strategies adopted by women and men.     

Dielectric and Material Properties of Poly (Vinyl Alcohol): Based Modified Red Mud Polymer Nanocomposites

Red mud emerges as the major waste material during production of alumina from bauxite by the Bayer??s process. Based on economics as well as environmental related issues, enormous efforts have been directed worldwide towards red mud management issues i.e. of utilization, storage and disposal. The present research work has been undertaken with an objective to explore the use of red mud as a reinforcing material in the polymer matrix as a low cost option. The silicate layered red mud was organophilized by aniline formaldehyde and to know the effect of various filler loading on the material properties of PVA-organophilized red mud composites, prepared by a conventional solvent casting technique and comparison of the same with that of the virgin poly (vinyl alcohol) (PVA), various characterizations was done. The modified red mud was typically characterized by X-ray diffraction. The X-ray diffraction pattern of the composite materials was also studied. The morphological image of the composite materials was studied by scanning electron microscopy (SEM). Transmission electron microscopy (TEM) was used to characterize the dispersion of the red mud within the composite materials. The surface topography of the composite materials was studied by Atomic Force Microscopy (AFM). The dielectric properties of composite materials were investigated in wide frequency ranges from 1?MHz to 1?GHz.