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261.
Baniel J  Ram Z  Kami A  Schindel D 《Disasters》1986,10(3):230-231
Toxicological mass disasters have occurred frequently in past years and constitute a permanent threat in urban areas. From the standpoint of hospital planning, special consideration is required to treat a large number of poisoned casualties in a relatively short period. Several unique medical aspects characterize toxicological mass disasters: casualties present a single disease entity with many "borderline" cases, most medical personnel are unfamiliar with the problem and casualties present a potential contamination hazard to the hospital. A hospital deployment scheme is presented recommending Decontamination, Triage and simple Treatment Algorithms to meet the medical and organizational challenge of such a mass casualty situation. A further specific deployment scheme for treatment of organophosphorus agents poisoning is described to illustrate the principles presented.  相似文献   
262.
Biomass burning is a common agricultural practice, because it allows elimination of postharvesting residues; nevertheless, it involves an inefficient combustion process that generates atmospheric pollutants emission, which has implications on health and climate change. This work focuses on the estimation of emission factors (EFs) of PM2.5, PM10, organic carbon (OC), elemental carbon (EC), carbon monoxide (CO), carbon dioxide (CO2), and methane (CH4) of residues from burning alfalfa, barley, beans, cotton, maize, rice, sorghum, and wheat in Mexico. Chemical characteristics of the residues were determined to establish their relationship with EFs, as well as with the modified combustion efficiency (MCE). Essays were carried out in an open combustion chamber with isokinetic sampling, following modified EPA 201-A method. EFs did not present statistical differences among different varieties of the same crop, but were statistically different among different crops, showing that generic values of EFs for all the agricultural residues can introduce significant uncertainties when used for climatic and atmospheric pollutant inventories. EFs of PM2.5 ranged from 1.19 to 11.30 g kg?1, and of PM10 from 1.77 to 21.56 g kg?1. EFs of EC correlated with lignin content, whereas EFs of OC correlated inversely with carbon content. EFs of EC and OC in PM2.5 ranged from 0.15 to 0.41 g kg?1 and from 0.33 to 5.29 g kg?1, respectively, and in PM10, from 0.17 to 0.43 g kg?1 and from 0.54 to 11.06 g kg?1. CO2 represented the largest gaseous emissions volume with 1053.35–1850.82 g kg?1, whereas the lowest was CH4 with 1.61–5.59 g kg?1. CO ranged from 28.85 to 155.71 g kg?1, correlating inversely with carbon content and MCE. EFs were used to calculate emissions from eight agricultural residues burning in the country during 2016, to know the potential mitigation of climatic and atmospheric pollutants, provided this practice was banned.

Implications: The emission factors of particles, short-lived climatic pollutants, and atmospheric pollutants from the crop residues burning of eight agricultural wastes crops, determined in this study using a standardized method, provides better knowledge of the emissions of those species in Latin America and other developing countries, and can be used as inputs in air quality models and climatic studies. The EFs will allow the development of more accurate inventories of aerosols and gaseous pollutants, which will lead to the design of effective mitigation strategies and planning processes for sustainable agriculture.  相似文献   
263.
The Clean Development Mechanism (CDM) under the Kyoto Protocol to the United Nations Framework Convention on Climate Change is considered a key instrument to encourage developing countries' participation in the mitigation of global climate change. Reduction of greenhouse gas (GHG) emissions through the energy supply and demand side activities are the main options to be implemented under the CDM. This paper analyses the general equilibrium effects of a supply side GHG mitigation option-the substitution of thermal power with hydropower--in Thailand under the CDM. A static multi-sector general equilibrium model has been developed for the purpose of this study. The key finding of the study is that the substitution of electricity generation from thermal power plants with that from hydropower plants would increase economic welfare in Thailand. The supply side option would, however, adversely affect the gross domestic product (GDP) and the trade balance. The percentage changes in economic welfare, GDP and trade balance increase with the level of substitution and the price of certified emission reduction (CER) units.  相似文献   
264.
ABSTRACT: Physically-based models are extensively used to simulate the infiltration process under varied field conditions. Most models are based on the deterministic nature of input parameters related to the flow process (such as hydraulic conductivity). These models yield poor predictions of infiltration rates because they do not include the field-scale variations of flow parameters. The paper presents an approach for integrating the field-scale variability of hydraulic conductivity with an infiltration model to simulate infiltration under the rainfall conditions. A model describing the spatial structure of hydraulic conductivity has been developed using stochastic techniques. The stochastic structure of hydraulic conductivity was then incorporated in the Green-Ampt and Mein-Larson infiltration model. The model outputs on the instantaneous infiltration rates and cumulative infiltration were evaluated using the field infiltration data measured under simulated rainfall conditions. The results show that the combined model is capable of rep. resenting the instantaneous infiltration rates and cumulative infiltration of the study soils. The model may, therefore, be used to simulate the rainfall infiltration process for spatially-variable soils under the field conditions.  相似文献   
265.
As more people visit natural areas for tourism and recreation purposes, it is becoming increasingly important to understand the value they place on these natural resources. Specifically, tourists to Florida have been increasingly interested in visiting natural areas, forests, parks, and preserves-highlighting the importance of this new and growing phenomenon. We analyze visitors' demand for nature-based recreation in the Apalachicola River region of Florida using the travel cost method. The results from a count data regression model reveal that on average visitors would pay 74.18 dollars per visit-day for nature-based recreation resulting in a total economic value of 484.56 million dollars attributable to nature-based recreation in the Apalachicola River region. Results of this study provide useful information for natural resources management in the region and a rationale to preserve Florida's unique ecosystems.  相似文献   
266.
Biodiversity conservation and management of natural resources are the best options to restore and increase productivity of degrading pastureland in dry areas. Hence, arthropod abundance, organic matter, respiration, and dehydrogenase activity were measured in canopy zone soil of Prosopis cineraria (PC), Acacia nilotica (AN), Zizyphus nummularia (ZN), Capparis decidua (CD), and Acacia senegal (AS) associated with grasses with a view to establish interrelation for productivity enhancement of pastureland. Pure grass bock outside tree canopy was control plot. Acari, Myriapoda, Coleoptera, Isoptera, Collembola, and other soil arthropods were the major soil faunal groups. Integration of tree in pastureland enhanced population of soil arthropod by 9–65-fold in May 2001 and 8–13-fold in August/September as compared with control. The trends of changes in soil organic matter (SOM), soil respiration (SR), and dehydrogenase activity (DHA) were similar to the changes in soil arthropod population, indicating the role of soil fauna in facilitating biochemical processes and soil fertility. Two, eight, and nine times greater SOM, SR, and DHA, respectively, in silvipastoral system than the values in control suggest the beneficial effects of trees on improvement in biochemical processes and thus biodiversity in pastureland, as supported by negative values of relative tree effects (RTE). Microbial activities were highest in the ZN system, which had highest abundance of soil arthropods. In the other systems, CD and AS systems showed greater soil arthropod abundance and biological activities than with the PC and AN systems. Therefore, Z. nummularia-, C. decidua-, and A. senegal-based silvipastoral systems and related soil fauna may be promoted for enhancement of biological activity and productivity of pastureland in desert. The strategy may be adopted for developing a sustainable pedoecosystem in a region of the world where agriculture is notoriously difficult.  相似文献   
267.
Duckweed (Lemna minor) a small vascular plant, grows rapidly, is sensitive to a wide variety of toxicants and is easy to culture. A method is described that measures duckweed frond growth, chlorophyll, protein and biomass content as indicator of growth inhibition. The physico-chemical analysis of anaerobically treated distillery effluent revealed high BOD (28,000 mg/l), COD (52,400 mg/l) and dark brown colour (180,000 Co. Pt.). This effluent showed high toxicity to Lemna minor after 96 h of exposure in laboratory condition. EC50 of the fronds for chlorophyll, protein and biomass was found to be 25%, however, the bacterial decolourised effluent showed reduction of BOD (87.50%), COD (84.50%) and colour (76%). Further the toxicity evaluation with Lemna minor showed toxicity reduction up to 63% for all tested parameters. The EC50 noted for chlorophyll, protein and biomass was 100% concentration of decolourised effluent.  相似文献   
268.
Environmental Science and Pollution Research - Metalloids are a subset of particular concern to risk assessors and toxicologists because of their well-documented potential hazards to plant system....  相似文献   
269.
Sugarcane molasses-based distillery spent wash (DSW) is well known for its toxicity and complex mixture of various recalcitrant organic pollutants with acidic pH, but the chemical nature of these pollutants is unknown. This study revealed the presence of toxic organic acids (butanedioic acid bis(TMS)ester; 2-hydroxysocaproic acid; benzenepropanoic acid, α-[(TMS)oxy], TMS ester; vanillylpropionic acid, bis(TMS)), and other recalcitrant organic pollutants (2-furancarboxylic acid, 5-[[(TMS)oxy] methyl], TMS ester; benzoic acid 3-methoxy-4-[(TMS)oxy], TMS ester; and tricarballylic acid 3TMS), which are listed as endocrine-disrupting chemicals. In addition, several major heavy metals were detected, including Fe (163.947), Mn (4.556), Zn (2.487), and Ni (1.175 mg l?1). Bacterial community analysis by restriction fragment length polymorphism revealed that Bacillus and Stenotrophomonas were dominant autochthonous bacterial communities belonging to the phylum Firmicutes and γ-Proteobacteria, respectively. The presence of Bacillus and Stenotrophomonas species in highly acidic environments indicated its broad range adaptation. These findings indicated that these autochthonous bacterial communities were pioneer taxa for in situ remediation of this hazardous waste during ecological succession. Further, phytotoxicity assay of DSW with Phaseolus mungo L. and Triticum aestivum revealed that T. aestivum was more sensitive than P. mungo L. in the seed germination test. The results of this study may be useful for monitoring and toxicity assessment of sugarcane molasses-based distillery waste at disposal sites.  相似文献   
270.
Indigenous Heavy Metal Multiresistant Microbiota of Las Catonas Stream   总被引:1,自引:0,他引:1  
Las Catonas stream (Buenos Aires Metropolitan Area) receives a complex mixture of pollutants from point and diffuse sources because of the agricultural, industrial and urban land uses of its basin. Widespread detection of heavy metals exceeding aquatic life protection levels has occurred in monitoring reconnaissance studies in surface and pore water. As a result of the screening of Cu, Cd, Zn and Pb resistant/tolerant and culturable microbiota, B101N and 200H strains (Pseudomonas fluorescens or putida) were isolated and selected for further studies. They showed 65% Cd and 35% Zn extraction efficiency from aqueous phase. The potential use of these strains in wastewater treatment is currently investigated in order to contribute to decrease heavy metal pollution, a problem affecting every stream of Buenos Aires Metropolitan Area.  相似文献   
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