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51.
Ram LC Srivastava NK Tripathi RC Jha SK Sinha AK Singh G Manoharan V 《Journal of environmental management》2006,79(2):173-187
Long-term field trials using lignite fly ash (LFA) were carried out in rice crops during the period 1996-2000 at Mine I, Neyveli Lignite Corporation, Tamil Nadu. LFA, being alkaline and endowed with an excellent pozzolanic nature, silt loam texture, and plant nutrients, has the potential to improve the texture, fertility, and crop productivity of mine spoil. The rice crops were the first, third, fifth, and sixth crops in rotation. The other crops, such as green gram (second) and sun hemp (fourth), were grown as green manure. For experimental trials, LFA was applied at various dosages (0, 5, 10, 20, 50, 100, and 200 t/ha), with and without press mud (10 t/ha), before cultivation of the first crop. Repeat applications of LFA were made at the same dosages in treatments of up to 50 t/ha (with and without press mud) before cultivation of the third and fifth crops. Press mud, a lightweight organic waste product from the sugar industry, was used as an organic amendment and source of plant nutrients. Also, a recommended dosage of chemical fertilizer, along with gypsum, humic acid, and biofertilizer as supplementing agents, was applied in all the treatments, including control. With one-time and repeat applications of LFA, from 5 to 20 t/ha (with and without press mud), the crop yield (grain and straw) increased significantly (p < 0.05), in the range from 3.0 to 42.0% over the corresponding control. The maximum yield was obtained with repeat applications of 20 t/ha of LFA with press mud in the third crop. The press mud enhanced the yield in the range of 1.5-10.2% with various dosages of LFA. The optimum dosage of LFA was 20 t/ha for both one-time and repeat applications. Repeat applications of LFA at lower dosages of up to 20 t/ha were more effective in increasing the yield than the corresponding one-time applications of up to 20 t/ha and repeat applications at 50 t/ha. One-time and repeat applications of LFA of up to 20 t/ha (with and without press mud), apart from increasing the yield, evinced improvement in the texture and fertility of mine spoil and the nutrient content of crop produce. Furthermore, some increase in the content of trace and heavy metals and the level of gamma-emitters in the mine spoil and crop produce was observed, but well within the permissible limits. The residual effect of LFA on succeeding crops was also encouraging in terms of eco-friendliness. Beyond 20 t/ha of LFA, the crop yield decreased significantly (p < 0.05), as a result of the formation of hardpan in the mine spoil and possibly the higher concentration of soluble salts in the LFA. However, the adverse effects of soluble salts were annulled progressively during the cultivation of succeeding crops. A plausible mechanism for the improved fertility of mine spoil and the carryover or uptake of toxic trace and heavy metals and gamma-emitters in mine spoil and crop produce is also discussed. 相似文献
52.
García-Nieto PJ 《Journal of environmental management》2006,79(4):372-382
This paper studies the scavenging efficiencies of aerosol emissions from coal-fired power plants under different removal mechanisms (coagulation, heterogeneous nucleation and gravitational settling) as a function of time. It also analyses the ‘health impact’ of the aerosol before and after the above dynamic mechanisms by comparing the respirable dust fractions. The well-known equations of evolution are applied to an average PSD that represents the exhaust particulate emissions from coal-fired power plants (i.e. Aboño power plant in Asturias that belongs to Hidrocantábrico Group, S.A.). From this study it is inferred that respirable dust is scavenged with the greatest difficulty and when compared with the initial volume of respirable dust, roughly 20% remains after 18 h of gravitational settling. Therefore, gravitational settling is the main removal mechanism of respirable dust compared to condensation and coagulation. 相似文献
53.
de Carvalho George Harrison Ferreira de Andrade Milene Aparecida de Araújo Carla Nunes Santos Maria Lucília de Castro Natália Alves Charneau Sébastien Monnerat Rose de Santana Jaime Martins Bastos Izabela Marques Dourado 《Environmental science and pollution research international》2019,26(6):5514-5523
Environmental Science and Pollution Research - Aedes aegypti and Culex quinquefasciatus are vectors of diseases that constitute public health problems. The discovery of products capable of... 相似文献
54.
Segovia-Sandoval Sonia Judith Padilla-Ortega Erika Carrasco-Marín Francisco Berber-Mendoza María Selene Ocampo-Pérez Raúl 《Environmental science and pollution research international》2019,26(25):25916-25931
Environmental Science and Pollution Research - In this work, it was analyzed the behavior of three commercial activated carbons with different textural and chemical properties to adsorb... 相似文献
55.
David A. Ross Héctor M. Guzmán Vincent J. Van Hinsberg Catherine Potvin 《Journal of environmental science and health. Part. B》2016,51(10):675-687
Concentrations of eight elements were measured in Chelonia mydas and Lepidochelys olivacea eggs collected along the Pacific coast of Panama. Manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), and mercury (Hg) concentrations were similar to previous reports of these species from around the world, while lead (Pb) was lower than previous reports. Cd posed the highest health risk to people who regularly eat the eggs, with average consumption rates leading to target hazard quotients (THQ) of up to 0.35 ± 0.15. Our conclusions indicate that current turtle egg consumption in isolated, coastal Pacific communities may pose a health concern for young children, and that youth and young adults should limit their consumption of turtle eggs to reduce their total intake of nonessential metals. 相似文献
56.
Throughout Europe, the role of farming as the private provider of public goods and services increasingly valuated by society
is today generally acknowledged. Furthermore, in the turn towards rural development concerns, multifunctionality as an attribute
of rural space has emerged, justifying the territorial approach of farming. The situation facing the multifunctionality demand
is nevertheless not the same in all European regions, which by all means is getting strengthened in the transition towards
post-productivism. In some regions, there is a productivist orientation and production has a dominant economic role, while
others will need to be supported on other functions to survive economically and socially, or may be best suited to environmental
functions alone. The vocation of the rural territories is different, and thus also the functions they are able to support.
This paper discusses the concept of multifunctionality of the rural areas, and defines a possible methodological approach
towards the identification of the different types of rural areas in Europe, based on the identification of ideal types, through
the analysis of selected indicators. The empirical application has been developed for the Portuguese Ministry of Agriculture,
aiming at assessing the differentiated characteristics and dynamics of the Portuguese rural territory. Analyzing data from
1990 and 2000, at municipal level, three dimensions have been considered: the land cover, the agricultural sector and the
rural community. Combining the three analyses, it was possible to identify different vocations of the rural space, and the
role that farming could have in the future for the multifunctionality of the territory. Accordingly, the municipalities have
been grouped in types, pre-defined as ideal types. This was a first attempt to understand the differentiation of the rural
territory in Portugal. For decision-making it should be further developed. It nevertheless shows that there is clear differentiation
concerning the possible landscape functions to be developed between regions and a possible way to assess. It also shows that
a territorial approach to agriculture may be the key for the maintenance of the sector in many areas where production by itself,
as it has been know until now, may be severely threatened. 相似文献
57.
Plaza C Xing B Fernández JM Senesi N Polo A 《Environmental pollution (Barking, Essex : 1987)》2009,157(1):257-263
Binding of two model polycyclic aromatic hydrocarbons (PAHs), phenanthrene and pyrene, by humic acids (HAs) isolated from an organic substrate at different stages of composting and a soil was investigated using a batch fluorescence quenching method and the modified Freundlich model. With respect to soil HA, the organic substrate HA fractions were characterized by larger binding affinities for both phenanthrene and pyrene. Further, isotherm deviation from linearity was larger for soil HA than for organic substrate HAs, indicating a larger heterogeneity of binding sites in the former. The composting process decreased the binding affinity and increased the heterogeneity of binding sites of HAs. The changes undergone by the HA fraction during composting may be expected to contribute to facilitate microbial accessibility to PAHs. The results obtained also suggest that bioremediation of PAH-contaminated soils with matured compost, rather than with fresh organic amendments, may result in faster and more effective cleanup. 相似文献
58.
Tim S. Nawrot Nino Kuenzli Jordi Sunyer Tingming Shi Teresa Moreno Mar Viana Joachim Heinrich Bertil Forsberg Frank J. Kelly Muhammad Sughis Benoit Nemery Paul Borm 《Atmospheric environment (Oxford, England : 1994)》2009,43(30):4595-4602
We assessed the extent to which constituents of PM2.5 (transition metals, sodium, chloride) contribute to the ability to generate hydroxyl radicals (OH) in vitro in PM2.5 sampled at 20 locations in 19 European centres participating in the European Community Respiratory Health Survey. PM2.5 samples (n = 716) were collected on filters over one year and the oxidative activity of particle suspensions obtained from these filters was then assessed by measuring their ability to generate OH in the presence of hydrogen peroxide. Associations between OH formation and the studied PM constituents were heterogeneous. The total explained variance ranged from 85% in Norwich to only 6% in Albacete. Among the 20 centres, 15 showed positive correlations between one or more of the measured transition metals (copper, iron, manganese, lead, vanadium and titanium) and OH formation. In 9 of 20 centres OH formation was negatively associated with chloride, and in 3 centres with sodium. Across 19 European cities, elements which explained the largest variations in OH formation were chloride, iron and sodium. 相似文献
59.
Chester W. Spicer Michael W. Holdren Kenneth A. Cowen Darrell W. Joseph Jan Satola Bradley Goodwin Howard Mayfield Alexander Laskin M. Lizabeth Alexander John V. Ortega Matthew Newburn Robert Kagann Ram Hashmonay 《Atmospheric environment (Oxford, England : 1994)》2009,43(16):2612-2622
Aircraft emissions affect air quality on scales from local to global. More than 20% of the jet fuel used in the U.S. is consumed by military aircraft, and emissions from this source are facing increasingly stringent environmental regulations, so improved methods for quickly and accurately determining emissions from existing and new engines are needed. This paper reports results of a study to advance the methods used for detailed characterization of military aircraft emissions, and provides emission factors for two aircraft: the F-15 fighter and the C-130 cargo plane. The measurements involved outdoor ground-level sampling downstream behind operational military aircraft. This permits rapid change-out of the aircraft so that engines can be tested quickly on operational aircraft. Measurements were made at throttle settings from idle to afterburner using a simple extractive probe in the dilute exhaust. Emission factors determined using this approach agree very well with those from the traditional method of extractive sampling at the exhaust exit. Emission factors are reported for CO2, CO, NO, NOx, and more than 60 hazardous and/or reactive organic gases. Particle size, mass and composition also were measured and are being reported separately. Comparison of the emissions of nine hazardous air pollutants from these two engines with emissions from nine other aircraft engines is discussed. 相似文献
60.
Gabriel Ibarra-Berastegi Jon Sáenz Agustín Ezcurra Unai Ganzedo Javier Díaz de Argandoña Iñigo Errasti Alejandro Fernandez-Ferrero Josué Polanco-Martínez 《Atmospheric environment (Oxford, England : 1994)》2009,43(25):3829-3836
In Bilbao (Spain), an air quality network measures sulphur dioxide levels at 4 locations. The objective of this paper is to develop a practical methodology to identify redundant sensors and evaluate a network's capability to correctly follow and represent SO2 fields in Bilbao, in the frame of a continuous network optimization process.The methodology is developed and tested at this particular location, but it is general enough to be useable at other places as well, since it is not tied neither to the particular geographical characteristics of the place nor to the phenomenology of the air quality over the area.To assess the spatial variability of SO2 measured at 4 locations in the area, three different techniques have been used: Self-Organizing Maps (SOMs), cluster analysis (CA) and Principal Component Analysis (PCA). The results show that the three techniques yield the same results, but the information obtained via PCA can be helpful not only for that purpose but also to throw light on the major mechanisms involved. This might be used in future network optimization stages. The main advantage of cluster analysis and SOMs is that they provide readily interpretable results. All the calculations have been carried out using the freely available software R. 相似文献