INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY (IJEST)
Year:2009 | Volume:6 | Issue:2 (22)|Papers Count:20

Though quarantine disinfestations treatments have been exempt from the methyl bromide phase out, it is still required to research and develop alternative treatments for fumigation of plant material in transit. This study investigated the ability of both the egg and pupal stages of the quarantine pest, South Americian leafminer, Liriomyza huidobrensis to survive submersion in water heated to temperatures between 40 and 50°C for varying periods of time. Large reductions in egg viability were recorded. However, the treatments also resulted in unacceptable levels of damage to the host plant material. Damage was uneconomically viable. Pupae were all killed exposure to water at 44°C for 20 min. Incubation of insect and plant material at either 5 or 20°C for 24 h before submersion in the hot water did not significantly alter the pests’ ability to survive the treatments. The potential of hot water treatments to act as an alternative to methyl bromide fumigation for disinfecting plants in transit is discussed.

The qualities of the treated final effluents of a wastewater treatment plant located in a rural community of the Eastern Cape province of South Africa were assessed over the duration of 12 months. Parameters measured include pH, temperature, electrical conductivity, salinity, turbidity, total dissolved solid, dissolved oxygen, chemical oxygen demand , nitrate, nitrite and orthophosphate levels and these were simultaneously monitored in the treated final effluents and the receiving watersheds using standard methods. Unacceptably, high levels of the assayed parameters were observed in many cases for chemical oxygen demand (7.5-248.5 mg/L), nitrate (1.82-13.14 mg/L), nitrite (0.09- 1.3 mg/L), orthophosphate (0.07-4.81 mg/L), dissolved oxygen (4.15-11.22 mg/L) and turbidity (3.68-159.06 NTU) during the study period and are severally outside the compliance levels of the South African guidelines and World Health Organization tolerance limits for effluents intended for discharge through public sewers into receiving watersheds. The study has revealed that there was an adverse impact on the physico-chemical characteristics of the receiving watershed as a result of the discharge of inadequately treated effluents from the wastewater treatment facility. This poses a health risk to several rural communities which rely on the receiving water bodies primarily as their sources of domestic water. There is need for the intervention of appropriate regulatory agencies to ensure production of high quality treated final effluents by wastewater treatment facilities in rural communities of South Africa.

The ability of light expanded clay aggregate to remove Pb++ and Cd++ from paint industry’s effluents was studied at different levels of adsorbent, contact time and pH in April 2008. For this purpose, Pb and Cd removal from paint industry effluents were studied in batch reactors. Pb and Cd measurements have been taken with non-flame atomic absorption techniques and test methods were adapted from 19 th edition of standard methods for the examination of water and wastewater. In this study, different amounts of Leca (1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 g/L) were investigated. The amount of adsorbed Pb (II) and Cd (II) exposure to Leca increased from 1.41 to 3 mg/g and 0.22 to 0.75 mg/g, respectively. The maximum removal efficiency for Pb was 93.75 % at pH = 7 and exposure to 10 g/L of Leca, while for Cd, it was nearly 89.7 % at the same condition. In this study, adsorption process of lead and cadmium was fitted with Freundlich adsorption isotherm (R2 Pb = 0.97 and R2 Cd = 0.98). The sufficient contact time was deemed 1-2 h for Cd and Pb. According to the results, Leca is recommended as a low cost and available adsorbent to remove lead and cadmium from industrial wastewater.

In pesticide applications, small droplets are desired for better coverage and uniform distribution. Yet, small droplets have a problem: Drift, the movement of droplets off-target. Low drift nozzle produces fewer drift-prone droplets, < 100 mm, compared to standard hydraulic nozzles. In pesticide applications, standard hydraulic nozzles, hollow cone and flat fan nozzles are generally used by farmers. These nozzles have broad droplet spectrum and high proportion drift-prone droplets. Sample of drifted droplets and measurements in field conditions are expensive and can be time-consuming. However, models can be applied to predict drift without field measurement. In this study, model and field measurement of percentage pesticide drift were compared using different hydraulic nozzles, D4-45, F 11006 and LD 11003 by gas chromatography equipped with a nitrogen-phosphorus detector. In the result of this study, for all nozzles, values up to 2 m and 3 m showed that there were statistically different according to German model and Dutch model, respectively. In the result of this study, percentage drift at 5 m compared to 1 m distance decreased approximately 15 folds in LD 11003, 12 in F 11006 and 10 folds in HC D4-45 nozzles in actual application and 5 folds in German and 9 folds in Dutch models.

Biofouling is the undesirable accumulation of microorganisms, plants, algae and animals on submerged structures especially ship hulls. Biofouling also occurs on the surface of living marine organisms. It is also found on membrane systems such as membrane bioreactors and reverse osmosis spiral wound membranes. In the same manner, it is found in cooling water cycles of large industrial equipments and power stations. In the present study, totally 11 isolates were obtained from three ships from Royapuram harbour, Chennai, Tamil Nadu, India. Among the 11 isolates only DR4 showed maximum biofouling activity in the microtiter plate assay with a significant OD of 0.596. Also an attempt was made to characterize the different biofouling bacterial isolates analyzing their morphological, biochemical and molecular characteristics. The results of the present study based on the above characteristics revealed that the isolate DR4 was similar to Bacillus sp. This study also highlights the need for a safe and natural antifouling agent to control the biofouling bacteria in the marine environment.

Mathematical simulations on dam break or failure using Boss Dambrk hydrodynamic flood routing dam break model were carried out to determine the extent of flooding downstream, flood travel times, flood water velocities, and impacts on downstream affected residences, properties and environmental sensitive areas due to floodwaters released by failure of the dam structure. Computer simulations for one of the worse-case scenarios on dam failure using BOSS DAMBRK software accounted for dam failure, storage effects, floodplains, over bank flow and flood wave attenuation. The simulated results reviewed a maximum flow velocity of 2.40 m/s with a discharge (Q) of approximately 242 m³/s occurred at 1.00 km downstream. The maximum discharge increased from 244 m3/s (flow velocity = 1.74 m/s occurred at 8th km) to 263 m3/s (flow velocity = 1.37 m/s occurred at 12th km); about a 39% drop in flow velocity over a distance of 4.00 km downstream. If the entire dam gives way instantly, some spots stretching from 0.00 km (at dam site) to approximately 3.40 km downstream of the dam may be categorized as “danger zone”, while downstream hazard and economic loss beyond 3.40 km downstream can be classified as “low” or “minimal” zones.

The effect of various concentrations of crude oil on fungal populations of soil was investigated for a period of 18 weeks using standard methods. Total fungal counts ranged from 26 to 143 x 102 cfu/gsoil while counts of petroleum-utilizing fungi ranged from 2 to 102 × 102 cfu/g soil. Analysis of variance and randomized complete block design of counts of total fungi and petroleum-utilizers showed high significant difference between the control and the oil treated soils at p ee 0.05 level. Counts of petroleum-utilizers expressed as a percentage of the corresponding total fungal count of the soils ranged from 4.7 % to 58.8 %. Species of fourteen fungal genera were isolated from the soils. These include Alternaria, Aspergillus, Candida, Cephalosporium, Cladosporium, Fusarium, Geotrichum, Mucor, Penicillium, Rhizopus, Rhodotolura, Saccharomyces, Torulopsis and Trichoderma. Of these, ten were petroleum-utilizers and were all isolated from the control and 1 % oil treated soils. Only seven genera were isolated from the 5 % oil treated soil out of which five genera were petroleum-utilizers in both the 3 % and 5 % treatment. The decreasing order of occurrence of a variety of fungal genera (fungal diversity) of both total fungi and petroleum-utilizers is 0 % (control) > 0.5 % > 1 % > 3 % > 5 %. This order of fungal diversity is a reverse of the decreasing order of fungal counts of these same soils. This showed that higher concentrations of crude oil has adverse effect on fungal diversity while enhancing the population of a fewer fungi.

Biodiesel is an environmentally friend renewable diesel fuel alternative. Jatropha seeds can be a feedstock to produce a valuable amount of oil to be converted to biodiesel using transesterification reaction. Jatropha plant has been successfully grown in southern Egypt using primary treated municipal wastewater for its irrigation. A bench scale production of biodiesel from Jatropha oil (using methyl alcohol and NaOH as catalyst) was developed with methyl esters yield of 98 %. Biodiesel was produced on a pilot scale based on the bench scale experiment results with almost the same methyl esters yield of 98 %. The produced biodiesel was evaluated as a fuel and compared with petroleum diesel according to its physical and chemical parameters such as viscosity, flash point, pour point, cloud point, carbon residue, acid value and calorific value. The experimental techniques and product evaluation results show that such properties of the produced biodiesel are near to that of petroleum diesel. A mass balance representing the transesterification process is presented in this study. Glycerol of 85 % purity was produced and evaluated as a valuable byproduct of the process. Free fatty acids and sodium phosphate salts which have industrial interesting are also produced and evaluated.

Five sediment cores from the fresh water region of the vembanad wetland system were studied for the trace metal concentration was investigated in five sediment cores collected from the fresh water region of the Vembanad wetland system were studied. The average concentration of iron, manganese, nickel, copper, zinc, cadmium, lead, mercury and chromium were determined. The core samples were collected using gravity type corer, digested with a mixture of nitric acid and perchloric acid and analyzed by atomic absorption spectrophotometry. Heavy metals such as iron, copper, nickel and zinc reported enrichment towards the surface of the core sediment sample collected from the centre of the lake. Lead, cadmium and mercury showed uniform distribution throughout the core. Quality of the sediments were evaluated based on sediment quality guidelines, pollution load index, sum of toxic units and with effect range low/effect range median and threshold effect level/probable effect level values of Environmental Protection Agency guidelines. The degree of contamination for each station was determined. The concentration of different heavy metals has been compared with the world average concentration of shale values. Results of the analysis showed that Vembanad lake is facing serious metal pollution with increased rate of deposition.

Pesticide transport and transformation were modeled in soil column from the soil surface to groundwater zone. A one dimensional dynamic mathematical and computer model is formulated to simulate two types of pesticides namely 2,4-dichlorophenoxy acetic acid and 1,2-dibromo 3-chloro propane in soil column. This model predicts the behavior and persistence of these pesticides in soil column and groundwater. The model is based on mass balance equation, including convective transport, dispersive transport and chemical adsorption in the phases such as solid, liquid and gas. The mathematical solution is obtained by finite difference implicit method. The model was verified with experimental measurements and also with analytical solution. The simulation results are in good agreement with measured values. The major findings of this research are the development of the model which can calculate and predict the concentration of pesticides in soil profiles, as well as groundwater after 4, 12, 31 days of pesticide application under steady state and unsteady water flow condition. With the results of this study, the distribution of various types of pesticides in soil column to groundwater table can be predicted.

The present study explores the effectiveness of Typha domingensis leaf powder for simultaneous removal of aluminium, iron, zinc and lead ions from aqueous solution. Batch experiments were carried out in laboratory at room temperature and at initial ions concentrations simulating the concentrations of these cations in real wastewater samples. The sorption process was examined applying the first and second order kinetic mechanisms. The results were best described by the second order rate kinetics. The applicability of the three equilibrium isotherm models was investigated. The obtained data follow the three investigated isothermal models in the following order: Langmuir > Freundlich > Temkin, for all the studied metal ions. The infrared spectra of native and exhausted Typha leaf powder confirmed ions-biomass interactions responsible for sorption. The results showed that Typha domingensis leaf powder can easily be envisaged as a new low cost natural biosorbent for metal clean up operations in aquatic systems.

Sites co-contaminated with organic and metal pollutants are common and considered to be a more complex problem as the two components often causes a synergistic effect on cytotoxicity. Phytoremediation has been proposed as a cost-effective technology for treating heavy metal or organic contamination and may be suitable for remediation of co-contaminated soil. This study investigated the concurrent removal of pyrene and cadmium in cocontaminated soil by growing maize in a pot experiment. At the end of 60 day culture, pyrene in spiked soil diminished significantly, accounting for 21-31 % of the initial extractable concentration in unplanted soil and 12-27 % in planted soil. With the increment of cadmium level, the residual pyrene both in unplanted and planted soil tended to increase. Although the presence of cadmium increased the accumulation of pyrene in maize, plant accumulation only account for less than 0.30 % of the total amount of the dissipated pyrene in vegetated soils. It implied that plant-promoted microbial biodegradation was the predominant contribution to the plant-enhanced dissipation of pyrene in co-contaminated soil. Unlike pyrene, heavy metal cadmium cannot be degraded. It was observed that maize can concurrently removed about on the average 0.70 % of the total cadmium amount in soil by plant uptake, but Cd phytoextraction would be inhibited under contamination of pyrene. Maize CT38 can normally grow in the co-contaminated soil with high level Cd and pyrene and can effectively remedy the sites co-contaminated with these two types of contamination, which suggest the possibility of simultaneous phytoremediation of two different contaminant types.

The isolate Pseudomonas aeruginosa exhibited resistance to heavy metals such as cadmium, chromium, nickel and lead. Plasmid DNA was isolated from P. aeruginosa and designated as pBC15. The size of the plasmid DNA was approximately 23 kb. Escherichia coli DH5α was transformed with plasmid pBC15 subsequired resistance to nickel and ampicillin. The same size of the plasmid was isolated from E. coli transformant and separated on 0.7 % agarose gel electrophoresis. The restriction analysis of pBC15 showed that the plasmid DNA has single site for Bam HI and Eco RI and three sites for Xho I which were compared with 1 Kb DNA and λ Hind III digest molecular markers. Therefore, the size of the plasmid DNA of pBC15 was confirmed to be 23 kb. Curing was carried out by ethidium bromide, acridine orange, novobiocin, sodium dodechyl sulphate and elevated temperature (40°C). Transformation and curing results suggest that nickel and ampicillin resistance gene was conferred by plasmid DNA. Cadmium resistant gene was present on chromosomal DNA along with the gene for chromium resistance. Lead resistance gene was shown to be present on the chromosomal DNA rather than the plasmid DNA as the cured and uncured cultures remained similar in lead resistance. Therefore, the ability of P. aeruginosa resistant to nickel and ampicillin is plasmid mediated and transferable to other strains whereas cadmium, chromium and lead could be chromosomal encoded. The heavy metal and antibiotic resistances of P.aeruginosa can be used to exploit for clean up industrial wastewater and bioremediation of heavy metal contaminated soil.

The ability of Chromolaena odorata to accumulate and serve as biomarker to lead and cadmium metals pollution load had been revealed by this study. Samples of soils and Siam weed were collected to assess impacts of solid waste disposal and traffic density on the environment. Composite sample were collected from a solid waste dumpsite, three traffic polluted areas with varying traffic density and a background site distant from traffic. Concentration of eight elements: cadmium, cobalt, chromium, copper, iron, nickel, lead and zinc were determined in soil and plant samples and correlated together. Accumulative factors like pollution load index, transfer factor, contamination factor, enrichment factor were calculated for the metals in both plants and soils and used as basis for interpreting the state of the environment and ability of C. odorata to accumulate metals. The accumulative factors of plants were generally greater than that of soil samples indicating increased accumulative capacity of the plant. The accumulations of lead and cadmium in C. odorata were remarkable with contamination factor 10.51 and 23.50, respectively and mean enrichment factors 3.52 and 6.93, respectively. Other metals had lower accumulative factors. The distribution of metals and calculated factors placed solid waste disposal site as the most polluted site while the trend observed in areas with traffic pollution depicts the ability of C. odorata to clean up metal pollution by accumulating them. It can therefore be suggested that solid waste disposal negatively affects the environment more than traffic pollution subject to the volume of traffic.

The increasing needs for transportation of freight and passengers causes environmental impacts. Preventing studies for these impacts should be considered by logistics firms and encouraged by the regulations of authorities. An important contribution can be provided by determining the environmental effects of the transportation modes in specific regions and using the most convenient ones. In this study, multiple criteria decision-making techniques including, human judgments, tangible and intangible criteria and priorities are used. Fuzzy analytic hierarchy process and preference ranking organization method for enrichment evaluation, as two of the multi criteria decision-making methodologies, are integrated for ranking the transportation modes in terms of the environmental effects of them. The proposed decision-making process is applied to chose the environmentally convenient transportation mode with respect to the determined evaluation criteria in Marmara Region of Turkey. The results indicate that, the main problem for the Marmara Region about transportation aspects is to pass from the intensive utilization of the road  transportation mode to another one. In this study it is seen that the most convenient transformation mode in Marmara Region is the sea transportation mode.

Arsenic contaminated sludge can be found from the treatment of arsenic contaminated ground water. Lake of management and reuse of this sludge can create further environmental problem as there is probability of mixing with soil and water. In this paper, an effort is taken for the use of such waste. Here, effectiveness of using this sludge in making ornamental brick has been analyzed and justified. The detailed study was made upon the suitability of sludge in making bricks. Results of different tests indicate that sludge proportion is the key factor for determining the quality of ornamental bricks/tiles. The compressive strength of ornamental bricks decreases with increase of sludge proportion. This study showed that arsenic contaminated sludge could be used safely up to 4 % for making ornamental bricks. Because upper than this limit, the quality of bricks or tiles may be fallen considerably.

The soil liquefaction potential has been evaluated for the Ariana region because of its important socioeconomic interest and its location. Liquefaction susceptibility map is carried out using a decisional flow chart for evaluation of earthquake-induced effects, based on available data such as: paleoliquefaction, geological, groundwater depth, seismotectonic, sedimentary features and geotechnical parameters in particular laboratory testing like grain size analyses and state parameters. Survey results showed that some of these localities are considered as possible sites to soil liquefaction. Indeed, Quaternary alluvium deposits, paleo beaches and recent deposits that edge the lake and the sebka constitute the most susceptible locations to liquefaction. In the East and the West sides of the studied zone, quaternary deposits are less susceptible to the liquefaction due to the groundwater level deepening and to the relatively old age of the deposits. Elsewhere sedimentary formations are classified as non-liquefiable as they are heavily compacted and old.

Providing safety in roads for the purpose of protecting human assets and preventing social and economic losses resulted from road accidents is a significant issue. Identifying the traffic hot spots of the roads provides the possibility of promoting the road safety which is also related to investigate frequency and intensity of occurred accidents. Accidents are multidimensional and complicated events. Identifying the accident factors is based on applying a comprehensive and integrated system for making decisions. Therefore, applying common mathematical and statistical methods in this field can be resulted in some problems. Hence, the new research methods with abilities to infer meaning from complicated and ambiguous data seem useful. Therefore, along with identifying the traffic hot spots, adaptive Neuro-Fuzzy inference system is used to predict traffic hot spots on rural roads. In this process, a fuzzy inference system from Sugeno type is trained applying hybrid optimization routine (back propagation algorithm in combination with a least square type of method) and accident data of Karaj-Chalus road in Tehran province. Then the system was tested by a complete set of data. Finally, the stated system could predict 96.85 % of accident frequencies in the studied blocks. Furthermore, the amount of effective false negative in all cases included only 0.82 % of predictions, which indicated a good approximation of predictions and model credibility.

This research studies the impact of water level control structures on self-assimilative capacity of rivers and on fish habitat. Constructing a water level control structure in a river reach will alter its hydraulics and thus its water quality, thermal regime and fish habitat. A mathematical model is developed to simulate river hydraulics, water quality, temperature and fish habitat. Diurnal dissolved oxygen concentrations are investigated to show their impact on fish. A case of a Nile River reach was studied to investigate the impact of the existence of the Esna barrage on the water quality and fish in its upstream reach. The barrage has negative impacts on the upstream self-assimilative capacity of the rivers. The waste load that the river could absorb was only 54 % (at low flow) and 78 % (at high flow) of the entire load if no barrage was present. Including in the simulation of the effects of photosynthesis and respiration, the above mentioned percentages were raised to 54 % and 91 %, respectively. Although water level control structures have negative impacts on the upstream self-assimilative capacity of the rivers, they have positive effect on downstream DO concentrations due to reaeration that happens across them. Downstream DO concentration increased by 6 % from its upstream concentration value. The barrage has a positive effect on fish habitat in the upstream section. The weighted usable area of Tilapia fish is doubled in case of barrage existence. The barrage causes a slight decrease in water temperature that reaches an average of 0.13 degree in the month of June.

The present study aims to compute the temporal and spatial distribution of road traffic induced noise pollution in an urban environment by monitoring and mapping. The study area was the entire Asansol city of West Bengal, India. A total of 35 locations were selected for collection of data, classified as industrial, commercial, residential, sensitive and mixed areas according to the national regulatory standards. Noise recordings were conducted during morning and night hours. Day time Leq level ranged between 51.2 and 89.0 dB(A), whereas it ranged between 43.5 and 81.9 dB(A) during night. The average Ldn value was 73.28±8.51 dB(A) (Range: 55.1 – 87.3); The Traffic noise index (TNI) was 80.62 ± 15.88 dB(A) (Range: 49.4 - 115.8). The computed data were mapped by utilization of Geographic information system methodology that allowed the visualization and identification of the extent and distribution of sound pollution across the study area. This proves to be an ideal tool for carrying out noise impact assessments in urban settings. The study reveals that present noise level in all the locations exceeds the prescribed limit. Based on the finding, it can be mentioned that the population in this industrial town are exposed to significantly high noise level, which is caused mostly due to road traffic. The study reveals that vulnerable establishments like schools and hospitals are subjected to significantly high noise level throughout the day and immediate mitigatory measures are required to alleviate the problem.