Evaluating the effectiveness of fingerling stocking and ecological perspectives in enhancing fish harvest in a large tropical reservoir of Northern India

Environment, Development and Sustainability - The present study evaluated the effectiveness of stocking the Gangetic carps, viz. Labeo catla, Labeo rohita, and Cirrhinus mrigala, in a large...     

Adoption of green banking practices and environmental performance in Pakistan: a demonstration of structural equation modelling

Environment, Development and Sustainability - Banking industries are blamed to be among the major factors that affect global climate change both directly and indirectly. The green banking concept...     

Physiological and biochemical mechanisms of spermine-induced cadmium stress tolerance in mung bean (<Emphasis Type="Italic">Vigna radiata</Emphasis> L.) seedlings

The role of exogenous spermine (0.25 mM Spm, a type of polyamine (PA) in reducing Cd uptake and alleviating Cd toxicity (containing 1 and 1.5 mM CdCl₂ in the growing media) effects was studied in the mung bean (Vigna radiata L. cv. BARI Mung-2) plant. Exogenously applied Spm reduced Cd content, accumulation, and translocation in different plant parts. Increasing phytochelatin content, exogenous Spm reduced Cd accumulation and translocation. Spm application reduced the Cd-induced oxidative damage which was reflected from the reduction of H₂O₂ content, O₂ ^?– generation rate, lipoxygenase (LOX) activity, and lipid peroxidation level and also reflected from the reduction of spots of H₂O₂ and O₂ ^?– from mung bean leaves (compared to control treatment). Spm pretreatment increased non-enzymatic antioxidant contents (ascorbate, AsA, and glutathione, GSH) and activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR) which reduced oxidative stress. The cytotoxicity of methylglyoxal (MG) is also reduced by exogenous Spm because it enhanced glyoxalase system enzymes and components. Through osmoregulation, Spm maintained a better water status of Cd-affected mung bean seedlings. Spm prevented the chl damage and increased its content. Exogenous Spm also modulated the endogenous free PAs level which might have the roles in improving physiological processes including antioxidant capacity, osmoregulation, and Cd and MG detoxification capacity. The overall Spm-induced tolerance of mung bean seedlings to Cd toxicity was reflected through improved growth of mung bean seedlings.     

Novel hybrid composite discharge electrode for electrostatic precipitator

Over the last few decades, electrostatic precipitators (ESPs) have emerged as effective air pollution control devices for treating coal-fired power plant exhausts. Among the components of the ESP, the discharge electrodes are extremely important in determining the collection efficiency of the ESP. Typically, in wet ESPs, the discharge electrodes used must be made of corrosion-resistant alloys, which makes them extremely expensive and heavy. Hybrid composite discharge electrodes have the potential to be lightweight and corrosion-resistant substitute for traditional metal alloy electrodes used in wet ESPs. In this experimental study, a novel hybrid composite electrode (recently patented at Ohio University) is presented as a substitute for traditional metal electrodes in wet ESPs. The samples of hybrid electrodes were fabricated by using carbon fiber composites, combined with metal mesh, in the shape of a long and thin tape. The electrode’s electrical response was evaluated in open atmospheric conditions, while connected to a transformer-rectifier unit to generate a corona current at voltages exceeding 50 kV. Results of these hybrid electrodes were compared with traditional metal electrodes. The hybrid composite discharge electrode produced a uniform corona at comparable power levels to that of metal electrodes, with additional advantages of being compact, lightweight, and highly corrosion resistant. In addition, hybrid composite electrodes exhibited lower corona onset voltage as compared with metal electrodes. The preliminary experimental data are encouraging and show significant potential for this new inexpensive hybrid electrode to replace metal electrodes in wet ESPs, providing comparable (and in some cases exceeding) collection efficiencies with lower ozone generation.

Implications: The newly invented hybrid composite electrode (HCE) performance was evaluated through experimentation with conventional metal electrodes. The HCE performance was comparable to the metal electrodes. The HCE also exhibited uniform corona fields and steady power while maintaining similar and in some cases superior electrical performance as compared with metal electrodes and thus shows a significant potential to substitute metal electrodes in wet ESP systems.     

Deterioration of water quality of Surma river

Surma River is polluted day by day by human activities, poor structured sewerage and drainage system, discharging industrial and household wastes. The charas (natural channels) are responsible for surface runoff conveyance from its urban catchments to the receiving Surma River. Water samples have been collected from a part of Surma River along different points and analyzed for various water quality parameters during dry and monsoon periods. Effects of industrial wastes, municipal sewage, and agricultural runoff on river water quality have been investigated. The study was conducted within the Chattak to Sunamganj portion of Surma River, which is significant due to the presence of two major industries – a paper mill and a cement factory. The other significant feature is the conveyors that travel from India to Chattak. The river was found to be highly turbid in the monsoon season. But BOD and fecal coliform concentration was found higher in the dry season. The water was found slightly acidic. The mean values of parameters were Conductivity 84–805 μs; DO: dry-5.52 mg/l, monsoon-5.72 mg/l; BOD: dry-1mg/l, monsoon-0.878 mg/l; Total Solid: dry-149.4 mg/l, monsoon-145.7 mg/l. In this study, an effort has been taken to investigate the status of concentration of phosphate (PO⁻⁴) and ammonia–nitrogen (NH₄–N) at four entrance points of Malnichara to the city, Guali chara, Gaviar khal and Bolramer khal. Data has been collected from March–April and September–October of 2004. Concentrations have been measured using UV Spectrophotometer. Although the phosphate concentration has been found within the limit set by DOE for fishing, irrigation and recreational purposes, however ammonia–nitrogen has been found to exceed the limit.     

Use of fungi for the bioconversion of rice straw into cellulase enzyme

Cellulase production was carried out by solid state bioconversion (SSB) method using rice straw, a lignocellulosic material and agricultural waste, as the substrate of three Trichoderma spp. and Phanerochaete chrysosporium in lab-scale experiments. The results were compared to select the best fungi among them for the production of cellulase. Phanerochaete chrysosporium was found to be the best among these species of fungi, which produced the highest cellulase enzyme of 1.43 IU/mL of filter paper activity (FPase) and 2.40 IU/mL of carboxymethylcellulose activity (CMCase). The “glucosamine” and “reducing sugar” parameters were observed to evaluate the growth and substrate utilization in the experiments. In the case of Phanerochaete Chrysosporium, the highest glucosamine concentration was 1.60 g/L and a high concentration of the release of reducing sugar was measured as 2.58 g/L obtained on the 4th day of fermentation. The pH values were also recorded. The range of the pH was about 5.15 to 5.56 in the case of Phanerochaete Chrysosporium.     

Microwave Assisted Synthesis of Urethane Modified Polyesteramide Coatings from Jatropha Seed Oil

In this study, we have developed urethane modified polyesteramide (UPEA) resin by the condensation polymerization reaction of N,N-bis (2-hydroxy ethyl) jatropha oil fatty amide (HEJA) and itaconic acid to form polyesteramide (PEA). The latter was further reacted with different percentages (16–22%) of toluylene 2,4-diisocyanate (TDI) to prepare UPEA. The structural elucidation of HEJA, PEA, UPEA was carried out by FT-IR, ¹H-NMR and ¹³C-NMR spectroscopic techniques. The coating was made on mild steel strips. The physico-chemical and physico-mechanical analyses were carried out by standard laboratory methods. The thermal stability of polymer was studied by thermogravimetric analysis. Thermal analyses shows that these coatings can be used safely up to 230 °C. The corrosion protective behavior of UPEA coatings was investigated in acid, alkali, water and xylene. All the coatings exhibited good chemical resistance performance in acid, alkali, saline and organic solvents, while the resin UPEA 20 showed the best performance.     

Agroforestry as a sustainable landuse option in degraded tropical forests: a study from Bangladesh

The tropical deciduous forest in Bangladesh provides a substantial part of country’s forest and where the government has introduced participatory agroforestry landuse. This study examined management issues, financial viability, and environmental as well as social sustainability of this landuse system. The forest department allocated a plot of size 1.0 ha among the selected participants where they were allowed to practice agriculture as well as to plant tree species for 10 years. The financial indicators indicated that the landuse system was profitable and attractive [net present value (NPV) = US$ 17,710 and benefit-cost ratio (BCR) = 4.12]. It was also viable and suitable from the social and environmental stand points. The study concluded that under the present environmental and socio-economic scenario, this production system could be the best management tool that would earn money, stop forest degradation, and finally be a model of sustainable land management in an overpopulated country.     

Physicochemical characterization of industrial effluents and their effect on fish survival.

Water samples taken from selected industrial drainages and receiving streams in and around Islamabad, Pakistan, during the summers of 1987 to 1990 showed disturbances in pH and low oxygen levels. Selected metals (Fe, Pb, Zn, Cd, Cu, Ni, Hg) were higher in all effluents than in receiving waters. Static bioassays of the undiluted industrial effluents from three sites caused 100% mortality in carp during the first 24 hrs. Fishes also suffered 30 to 60% mortality when exposed to other undiluted industrial effluents and some mortality when industrial effluents were diluted by 50%.