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Use of the antiozonant ethylenediurea (EDU) in Italy: Verification of the effects of ambient ozone on crop plants and trees and investigation of EDU's mode of action
2009
Paoletti, Elena | Contran, Nicla | Manning, William J. | Ferrara, Anna M.
Twenty-four experiments where EDU was used to protect plants from ozone (O3) in Italy are reviewed. Doses of 150 and 450 ppm EDU at 2-3 week intervals were successfully applied to alleviate O3-caused visible injury and growth reductions in crop and forest species respectively. EDU was mainly applied as soil drench to crops and by stem injection or infusion into trees. Visible injury was delayed and reduced but not completely. In investigations on mode of action, EDU was quickly (<2 h) uptaken and translocated to the leaf apoplast where it persisted long (>8 days), as it cannot move via phloem. EDU did not enter cells, suggesting it does not directly affect cell metabolism. EDU delayed senescence, did not affect photosynthesis and foliar nitrogen content, and stimulated antioxidant responses to O3 exposure. Preliminary results suggest developing an effective soil application method for forest trees is warranted. EDU was successful as a tool in determining ozone effects on vegetation in Italy, but while progress was made, its mode of action remains unresolved.
Show more [+] Less [-]A simple chemical free arsenic removal method for community water supply – A case study from West Bengal, India
2009
Sen Gupta, B. | Chatterjee, S. | Rott, U. | Kauffman, H. | Bandyopadhyay, A. | DeGroot, W. | Nag, N.K. | Carbonell-Barrachina, A.A. | Mukherjee, S.
This report describes a simple chemical free method that was successfully used by a team of European and Indian scientists (www.qub.ac.uk/tipot) to remove arsenic (As) from groundwater in a village in West Bengal, India. Six such plants are now in operation and are being used to supply water to the local population (www.insituarsenic.org). The study was conducted in Kasimpore, a village in North 24 Parganas District, approximately 25 km from Kolkata. In all cases, total As in treated water was less than the WHO guideline value of 10 μg L−1. The plant produces no sludge and the operation cost is 1.0 US$ per day for producing 2000 L of potable water. This work presents the chemical free arsenic removal method from groundwater and its successful implementation in West Bengal for community water supply.
Show more [+] Less [-]How do long-term development and periodical changes of river–floodplain systems affect the fate of contaminants? Results from European rivers
2009
Lair, G.J. | Zehetner, F. | Fiebig, M. | Gerzabek, M.H. | Gestel, C.A.M van | Hein, T. | Hohensinner, S. | Hsu, P. | Jones, K.C. | Jordan, G. | Koelmans, A.A. | Poot, A. | Slijkerman, D.M.E. | Totsche, K.U. | Bondar-Kunze, E. | Barth, J.A.C.
In many densely populated areas, riverine floodplains have been strongly impacted and degraded by river channelization and flood protection dikes. Floodplains act as buffers for flood water and as filters for nutrients and pollutants carried with river water and sediment from upstream source areas. Based on results of the EU-funded “AquaTerra” project (2004–2009), we analyze changes in the dynamics of European river–floodplain systems over different temporal scales and assess their effects on contaminant behaviour and ecosystem functioning. We find that human-induced changes in the hydrologic regime of rivers have direct and severe consequences on nutrient cycling and contaminant retention in adjacent floodplains. We point out the complex interactions of contaminants with nutrient availability and other physico-chemical characteristics (pH, organic matter) in determining ecotoxicity and habitat quality, and draw conclusions for improved floodplain management. Human activities have changed the hydraulics and contaminant fate in river–floodplain ecosystems.
Show more [+] Less [-]A coupled simulation-optimization approach for groundwater remediation design under uncertainty: An application to a petroleum-contaminated site
2009
He, L. | Huang, G.H. | Lu, H.W.
This study provides a coupled simulation-optimization approach for optimal design of petroleum-contaminated groundwater remediation under uncertainty. Compared to the previous approaches, it has the advantages of: (1) addressing the stochasticity of the modeling parameters in simulating the flow and transport of NAPLs in groundwater, (2) providing a direct and response-rapid bridge between remediation strategies (pumping rates) and remediation performance (contaminant concentrations) through the created proxy models, (3) alleviating the computational cost in searching for optimal solutions, and (4) giving confidence levels for the obtained optimal remediation strategies. The approach is applied to a practical site in Canada for demonstrating its performance. The results show that mitigating the effects of uncertainty on optimal remediation strategies (through enhancing the confidence level) would lead to the rise of remediation cost due to the increase in the total pumping rate. This study provides a coupled simulation-optimization approach for optimal design of groundwater remediation under uncertainty.
Show more [+] Less [-]Fluxes of Heavy Metals from a Highly Polluted Watershed During Flood Events: A Case Study of the Litavka River, Czech Republic
2009
Žák, Karel | Rohovec, Jan | Navratil, Tomas
The Litavka River (length 56 km, watershed area 630 km², average flow at the outlet to the Berounka River 2.57 m³ s⁻¹) drains the historical mining, ore processing, and smelting region of Příbram. This Ag-Pb-Zn±Sb ore district (production from the thirteenth century to 1978, locally to 1980) is known for extensive heavy metal contamination. Recent contamination of the Litavka River system is mostly related to the erosion of contaminated soils and fluvial floodplains sediments, especially from a low-gradient river section located immediately below the ore district, where the fine-grained floodplain sediments are from 1.0 to 1.7 m thick. Radiocarbon accelerator mass spectrometry dating of charcoal fragments separated from one floodplain profile showed calibrated ¹⁴C age in the range AD 1220-1284 at a depth of 1.2 m below the surface, while depths of 0.4 and 0.8 m yielded ages in the range AD 1680-1939. Formation of this floodplain was related to disturbance of the river equilibrium resulting from deforestation and the influx of fine-grained material from ore processing, including historical failures of settling ponds. Fluxes of heavy metals during flood events in the Litavka River were studied 35 km downstream below the ore district. Metals are transported here mostly (more than 99% for Pb) in the form of suspended particulate matter (SPM), which at the outlet of the Litavka River contains 2,016 mg kg⁻¹ Zn, 918 mg kg⁻¹ Pb, and 25.5 mg kg⁻¹ Cd on average. During a snowmelt-related minor flood event between March 25 and 29, 2006 (peak flow 36.6 m³ s⁻¹), the river transported 2,400 tonnes of SPM during 4 days, containing 74 kg of Cd, 2,954 kg of Pb, and 5,811 kg of Zn. During larger floods (water flows above 55 m³ s⁻¹ have occurred here 27 times during the last 77 years), the contamination is more diluted by material eroded in the floodplain along the middle and lower river course.
Show more [+] Less [-]Textile Effluents Affected Seed Germination and Early Growth of Some Winter Vegetable Crops: A Case Study
2009
Rehman, Abida | Bhatti, Haq Nawaz | Athar, Habib-ur-Rehman
In order to assess as to whether treated textile effluent could be safely used to irrigate some winter vegetables, growth room experiments were conducted. Varying levels of treated and untreated textile effluents were applied to germinating seeds of some winter vegetables and their effect was evaluated on germination and early growth stage using seed germination, growth, and biochemical attributes. From the results, it was obvious that textile effluent reduced seed germination and early growth of all vegetables. However, this effect was more pronounced at the highest concentration of textile effluent. Furthermore, treated textile effluent did not show any inhibitory effect on seed germination of all vegetables. Photosynthetic pigments such as chlorophyll a and b, and protein contents were higher in the leaves of all vegetable plants irrigated with treated textile effluent than those of supplied with untreated textile effluents. It has been observed that heavy metals were lower in concentration in treated textile effluent as compared with untreated textile effluent. However, germination and growth responses of all three vegetables were different to treated or untreated textile effluents. Furthermore, the Raphanus sativus ranked as tolerant followed by Brassica campastris and Brassica napus based on germination and growth responses. In conclusion, in view of shortage of water, textile effluent could safely be used for irrigation to vegetables after proper processing.
Show more [+] Less [-]Adaptive Grid Modeling with Direct Sensitivity Method for Predicting the Air Quality Impacts of Biomass Burning
2009
Unal, Alper
The objective of this study was to improve the ability to model the air quality impacts of biomass burning on the surrounding environment. The focus is on prescribed burning emissions from a military reservation, Fort Benning in Georgia, and their impact on local and regional air quality. The approach taken in this study is to utilize two new techniques recently developed: (1) adaptive grid modeling and (2) direct sensitivity analysis. An advanced air quality model was equipped with these techniques, and regional-scale air quality simulations were conducted. Grid adaptation reduces the grid sizes in areas that have rapid changes in concentration gradients; consequently, the results are much more accurate than those of traditional static grid models. Direct sensitivity analysis calculates the rate of change of concentrations with respect to emissions. The adaptive grid simulation estimated large variations in O₃ concentrations within 4 x 4-km² cells for which the static grid estimates a single average concentration. The differences between adaptive average and static grid values of O₃ sensitivities were more pronounced. The sensitivity of O₃ to fire is difficult to estimate using the brute-force method with coarse scale (4 x 4 km²) static grid models.
Show more [+] Less [-]An Analysis of the Indoor Air Quality and Mould Growth in a Multi-zone Building
2009
Chowdhury, Ashfaque Ahmed | Rasul, M. G | Khan, M. M. K
The effects of poor indoor air quality and mould growth in working environment are major problems in built environment, and there is a need to look for improvement of the health, comfort and productivity of the building occupants. Airborne mould sampling studies were conducted in a reference building located in Rockhampton, Central Queensland, Australia. Both indoor culturable and mould spore levels were observed. It was found through the indoor-outdoor ratios of the species that indoor concentrations are mostly related to the outdoor mould levels. The moulds differ in their relative humidity and temperature requirements to support surface growth. Indoor humidity has a significant effect on occupants comfort, perceived air quality, occupants' health, building durability, emissions and energy efficiency. Practical hygrothermal simulation models are employed to analyse the combined heat and moisture behaviour within the built environment. A review of the current modelling options available to predict building performance based on energy and mass transport simulation is presented, and then a case study is presented with the assessment of indoor built environment to avoid mould problem.
Show more [+] Less [-]Filtered Stepwise Clustering Method for Predicting Fate of Contaminants in Groundwater Remediation Systems: A Case Study in Western Canada
2009
Zou, Yun | Huang, Guo H. | Nie, Xianghui
This paper presents the development of a filtered stepwise clustering (FSC) method for facilitating the pump-and-treat (PAT) designs in groundwater remediation programs. To investigate the performances of different remediation strategies, a subsurface model is employed to simulate contaminant transport. Multivariate relationships between decision variables and selected modeling outputs are developed through the FSC method. Based on the developed statistical relationships, a set of possible outcomes for the remediation design can be presented; the solution space has been confined to a narrowed range. The proposed method can aid the PAT design by (a) quickly providing predicted outcomes given different remediation strategies and (b) directly locating the optimum remediation strategy for any outcome. The FSC method is examined through its application to a real-world aquifer remediation case in western Canada. The prediction results can help decision makers to evaluate the remediation design in an explicit way.
Show more [+] Less [-]Using multiple indices to evaluate scenarios for the remediation of contaminated land: the Porto Marghera (Venice, Italy) contaminated site
2009
Critto, Andrea | Agostini, Paola
Background, aim, and scope The management of contaminated sites requires the investigation of different involved aspects (from socioeconomic to risk and technological issues) and the presentation of useful and condensed information to decision makers. For this purpose, indices are more and more recognized as effective and valuable tools. This paper presents specific indices created within the DEcision Support sYstem for REhabilitation of contaminated sites (DESYRE). Materials and methods DESYRE is a software which aids decision making for the rehabilitation of a large contaminated site (i.e., megasite) by the creation and comparison of different rehabilitation alternatives. The software is composed of six modules, each dealing with a specific aspect of the remediation process, ending with the decision module. In this module, scenarios (i.e., suitable solutions for the rehabilitation of the contaminated site including selected land use, socioeconomic benefits, remediation costs, time span, environmental impacts, technology set/s, and residual risk) are created and evaluated by means of suitable indices. Nine indices cover the socioeconomic, risk, technological, cost, time, and environmental impact aspects. Mathematical algorithms are used to calculate these indices by taking into account data collected during the analytical steps of the DESYRE system and elaborated through the support of the spatial analysis, which is embedded in the system. Results The case study of Porto Marghera, Venice, Italy is presented in order to document the effectiveness of developed indices in evaluating management solutions and presenting options to decision makers. For the purpose of this study, three different scenarios for the remediation of a part of the site of Porto Marghera (approximately 530 ha) are developed and compared. The three scenarios consider the industrial land use and deal with the contamination in soil caused by inorganic and organic compounds. The scenarios mainly differ for the number of the included remediation technologies and for the spatial distribution of the technologies on the considered area. Discussion Indices results allow the user to more easily evaluate the advantages and limits of each scenario in order to select the most appropriate one. For instance, the risk indices allow the user to identify scenarios with good performance in reducing the extension of risk areas and the risk magnitude. Equally, the technological indices support the achievement of efficient remedial solutions characterized by a limited number of technologies, applied to extended areas and with high performance. The environmental impact index allows users to estimate the wider effects on the environment of the selected solutions, while the socioeconomic index is the result of social and economic investigations of the regional and local conditions, which ends with the identification of the best land use (e.g., the industrial one for the Porto Marghera area). Conclusions The proposed nine DESYRE indices provide more complete information to investigate suitable management solutions. DESYRE indices facilitate the definition of a consensus among stakeholders and the achievement of a widely shared solution for contaminated site management, even at larger sites, such as Porto Marghera. Recommendations and perspectives Further improvements to the system may be adopted, e.g., the possibility to aggregate results of the different assessments into one synthetic index per scenario or the inclusion of a Group Decision Making procedure.
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