Palm oil and its wastes as bioenergy sources: a comprehensive review

Environmental Science and Pollution Research - Due to global warming and increasing price of fossil fuel, scientists all over the world have been trying to find reliable alternative fuels. One of...     

Monitoring of growth and physiological activities of biofilm during succession on polystyrene from activated sludge under aerobic and anaerobic conditions

The present research work monitored the successive biofilm development and its catabolic role in the degradation of polystyrene (PS). PS material was artificially colonized with biofilm by incubating it with activated sludge under aerobic and anaerobic conditions. Biofilm formation was monitored by gravimetric weight analysis, spectrophotometric absorbance technique, heterotrophic plate count, and scanning electron microscopy under aerobic and anaerobic conditions. The wet weight (1.59 and 1.17 g) and dry weight (0.41 and 0.08 g) of a biofilm showed a significant constant increase under aerobic and anaerobic conditions, respectively, from first till 9 weeks of incubation. Plate count of the selected bacteria (Escherichia coli, Salmonella typhimurium, Shigella dysenteriae, Pseudomonas aeruginosa) considerably declined (90–99 %) in the biofilm after seventh and fifth weeks of incubation under aerobic and anaerobic conditions, respectively, indicating a positive shift from pathogenic to beneficial microbial community. While most probable number index of fecal coliforms and E. coli in the sludge showed more reduction (98 and 99 %) under aerobic as compare to anaerobic conditions (86 and 91 %) after 9 weeks of biofilm formation on PS cubes. Correspondingly, the decreasing levels of chemical oxygen demand and biochemical oxygen demand (up to 73 %) showed signs of sludge digestion. Scanning electron microscope coupled with energy dispersive X-ray spectroscope revealed nature of PS media containing high carbon content. However, biofilm development proved to be involved in the biochemical transformation of the PS medium as indicated by Fourier transform infrared spectroscopy.     

Approaches for prevention and environmental management of novel COVID-19

Environmental Science and Pollution Research - The World Health Organization (WHO) recognized a novel coronavirus as the causative agent of a new form of pneumonia. It was subsequently named...     

Community attitudes toward forest conservation programs through collaborative protected area management in Bangladesh

The formulation of conservation policies with options for creating protected areas is significantly influenced by the social factors of the surrounding communities. Therefore, indigenous knowledge, attitudes and perceptions of the local communities need to be explored during the planning and implementation stages of conservation projects. A government-initiated experiment in co-management was conducted in the Rema-Kalenga Wildlife Sanctuary, Bangladesh. This paper analyzes the attitudes toward conservation by members of local communities living in and around the wildlife sanctuary. Training incentives on alternative income-generating (AIG) activities and allotment of agricultural lands were distributed among the Forest User Groups. It is of interest to policy makers and resource managers whether this technique leads to improved attitudes on the part of local people. Although there were different attitudes toward protected areas and conservation, overall, a favorable attitude of the respondents was observed. The opinions of respondents also varied based on factors such as village position, village dependency level on forest resources, ethnicity and gender. Increase in annual income resulting from the augmented skills by trainings on AIG activities and getting agricultural lands leased from the Forest Department contributed significantly to the variation in respondents’ conservation attitudes. It is suggested that eliminating inequity and inequality in incentive distribution, discovering and launching training on more need-based livelihood activities, and liberalizing the restriction of resource extraction from the protected area by fixing the harvesting limit would encourage the community to be more cordially and actively involved in the conservation efforts of the sanctuary.     

How to bend down the environmental Kuznets curve: the significance of biomass energy

Sources of renewable energy have received wide attention in the literature because of serious threats to the environment. However, some renewable resources, including biomass energy role is debatable in the energy economics literature. This empirical work focuses to analyze the role of biomass energy in carbon dioxide (CO₂) emissions using the framework of the environmental Kuznets curve (EKC) in Pakistan over the period from 1980 to 2015. The bound testing approach suggests there is cointegration among study variables. The study uses an auto-regressive distributed lag model (ARDL) with a structural break in the series. To summarize the findings of the study, it can be inferred that biomass energy increase CO₂ emissions. In addition, biomass energy helps to form a U-shaped relationship between income and CO₂ emissions that support the EKC hypothesis. Also, the feedback hypothesis is found between biomass energy and CO₂ emissions. The findings would guide policymaker with practical guidelines to formulate policies to utilize a high amount of biomass energy in a sustainable manner.

     

Effect of cadmium on growth, ultramorphology of leaf and secondary metabolites of Phyllanthus amarus Schum. and Thonn

The pollution is increasing in the environment by different kinds of human activities, which results in the accumulation of heavy metals including cadmium in the soil and water and it causes different types of problems to living beings. As the plants are utilized by human being as food and medicine, therefore, it is mandatory to see the effect of metals on plants. In this context, efforts have been made to observe the effect of different concentration of Cadmium (Cd) on Phyllanthus amarus Schum. and Thonn., because Cd is the widespread metal and the plants response to low and high level of exposure is a complex phenomenon. P. amarus is mostly grown as weed in agricultural and waste lands. It is a reputed plant used in Indian indigenous systems of medicine with hepatoprotective, diuretic, stomachic properties and is recently being used for the treatment of hepatitis B. The study revealed that Cd causes significant decrease in fresh and dry weight, length of root and shoot, protein, chlorophyll, carotenoids and sugar and increase in starch content. It is interesting to note that the therapeutically active compounds—phyllanthin and hypophyllanthin, enhanced at certain levels of Cd due to abiotic stress. Besides, the ultramorpholical changes were also observed in stomatal opening and wax deposition on both the surfaces of leaves.     

Experimental investigation of energy properties for Stigonematales sp. microalgae as potential biofuel feedstock

Microalgae has been considered potential biofuel source from the last decade owing to its versatile perspectives such as excellent capability of CO₂ capture and sequestration, water treatment, prolific growth rate and enormous energy content. Thus, energy research on microalgae is being harnessed to mitigate CO₂ and meet future energy demands. This study investigated the bioenergy potential of native blue-green microalgae consortium as initial energy research on microalgae in Brunei Darussalam. The local species of microalgae were assembled from rainwater drains, the species were identified as Stigonematales sp. and physical properties were characterised. Sundried biomass with moisture content ranging from 6.5% to 7.37% was measured to be used to determine the net and gross calorific value and they were 7.98 MJ/kg-8.57 MJ/kg and 8.70 MJ/kg-9.45 MJ/kg, respectively. Besides that, the hydrogen content, ash content, volatile matter, and bulk density were also experimented and they were 2.56%-3.15%, 43.6%-36.71%, 57–38%-63.29% and 661.2 kg/m³-673.07 kg/m³, respectively. Apart from experimental values, other physical bioenergy parameters were simulated and they were biomass characteristic index 61,822.29 kg/m³-62,341.3 kg/m³, energy density 5.27 GJ/m³-5.76G J/m³ and fuel value index 86.19–88.54. With these experimental results, microalgae manifested itself a potential source of biofuel feedstock for heat and electricity generation, a key tool to bring down the escalated atmospheric greenhouse gases and an alternation for fossil fuel.