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901.
Amanda Lys dos Santos Silva Elane Cristina Loureno dos Santos Ana Maria Queijeiro Lpez 《Environmental science and pollution research international》2020,27(10):10275-10285
All processes in agro-industries consume water and generate large volumes of nutrient-rich effluents. To recycle effluents from a sugar–alcohol industry in the Northeastern Brazil (Coruripe, Alagoas), the effect of a daily application of a microbial formulation (containing five indigenous bacteria and two fungi), at the entrance of the two first facultative ponds (D, E) of its treatment plant formed by seven ponds (A–G), was evaluated in the sugarcane harvests of 2014/2015 and 2015/2016. Fortnightly, the values of 11 physicochemical parameters were checked and statistically compared (one and two-way ANOVA) in untreated (sedimentation pond A) and post-treated effluent (last facultative pond G), during both harvests. The treated effluent presented statistically significant improvements (p > 0.05), even between harvests, with averages of removal of organic matter of ca. 79.21% and 90.62%, and increases of the dissolved oxygen (DO) of ca. 72% and 74%, as well as the average increase of pH was ca. 42% and 50%. This better quality residue generally satisfied the class III level of the Brazilian Resolution 357/2005 (National Council for the Environment (CONAMA)), for water reuse in sugarcane irrigation on the yellow clay latosol soil, since it still is a light source of organic matter, nitrites and phosphorus, reducing the need of fertilizers for maintaining the productivity with low risk of salinization. According to Pearson’s bivariate correlation coefficient, while the DO and pH have positive correlation, they both have general inverse relation with the other physicochemical parameters evaluated and vice versa. 相似文献
902.
João P. F. Tiago Lázaro C. Sicupira Rodrigo E. Barros Gevany P. de Pinho 《Journal of environmental science and health. Part. B》2020,55(6):558-565
AbstractGlyphosate is the main herbicide currently used in the world due to wide applicability and efficiency in controlling weeds in many crops. However, its overuse may lead to undesirable impacts on the environment and to human health in the long run. This present study aimed to optimize and validate solid phase extraction (SPE) using an anionic resin for the simultaneous and direct determination of glyphosate and aminomethylphosphonic acid (AMPA) in water samples using high-performance liquid chromatography combined with inductively coupled plasma with triple quadrupole mass spectrometer (HPLC-ICP-MS/MS). The results showed that recovery percentage and relative standard deviation were 103.9?±?7.9 and 99.40?±?9.9% for glyphosate and AMPA, respectively. The validation certified that the method was precise, accurate, linear, and selective, with a limit of quantification of 1.09 and 0.29?μg L?1 for glyphosate and AMPA, respectively. The optimized methodology reached the concentration factor of 250 times and was successfully applied to analyze water samples from hydroponic cultivation of the eucalyptus seedlings. The results showed that the exudation process occurs at glyphosate doses starting from 2?L ha?1. 相似文献
903.
Esteves Gisele de Fátima Bressanin Leticia Aparecida de Souza Kamila Rezende Dázio da Silva Adriano Bortolotti Mantovani José Ricardo Marques Daniele Maria Magalhães Paulo César Pasqual Moacir de Souza Thiago Corrêa 《Environmental science and pollution research international》2020,27(31):38662-38673
Environmental Science and Pollution Research - The collapse of the Fundão dam in Mariana, MG, in 2015 resulted in the overflow of more than 50 million m3 of mud containing mine tailings,... 相似文献
904.
Esther Coz Begoña Artíñano Lisa M. Clark Mark Hernandez Allen L. Robinson Gary S. Casuccio Traci L. Lersch Spyros N. Pandis 《Atmospheric environment (Oxford, England : 1994)》2010,44(32):3952-3962
Scanning electron microscopy coupled to energy-dispersive x-ray spectroscopy (SEM/EDX) was used to quantify individual bioparticles in PM2.5 samples collected during the Pittsburgh Air Quality Study. Microscopy-based estimates of primary biogenic organic aerosol (PBOA) mass were compared to carbohydrate mass associated with PM2.5. Carbohydrates show substantial seasonal variations, with higher concentrations in the spring and the fall. During the summer, carbohydrates were about 30% of the estimated PBOA concentrations, but in the winter carbohydrate concentrations often greatly exceeded the PBOA mass estimate. Spores and insect detritus were the most abundant PBOA types in the summer samples, while winter samples were comprised predominantly of a mixture of microorganisms, insect and vegetative detritus. During the summer PBOA contributed on average 6.9 ± 5.4% by mass of the PM2.5 versus 3.3 ± 1.4% of the PM2.5 mass during the winter. 相似文献
905.
Sergio Machado Corrêa Graciela Arbilla Eduardo Monteiro Martins Simone Lorena Quitério Claudinei de Souza Guimarães Luciana Vanni Gatti 《Atmospheric environment (Oxford, England : 1994)》2010,44(19):2302-2308
The fuel matrix used in Brazil is unique around the world. The intensive use of hydrated ethanol, gasohol (gasoline with 25% v/v of ethanol), compressed natural gas (CNG), and biodiesel leads to a peculiar composition of the urban atmosphere. From 1998 to 2002 an increase in formaldehyde levels was observed and since then, a reduction. This work presents a monitoring campaign that was executed from March 2004 to February 2009 by sampling at early morning on every sunny Wednesday for a total of 183 samples. The results indicate a strong reduction in formaldehyde levels from 2004 (average of 135.8 μg m?3 with SD 28.4 μg m?3) to 2009 (average of 49.3 μg m?3 with SD 27.4 μg m?3). The levels of acetaldehyde showed a slight reduction from 2004 (average of 34.9 μg m?3 with SD 8.0 μg m?3) to 2009 (average of 26.8 μg m?3 with SD 11.5 μg m?3). Comparing the results with the concurrent evolution of the fleet and of fuel composition indicates that the observed formaldehyde levels could be associated with the increase in ethanol use and in CNG use by engines with improved technology over the first converted CNG engines. Modelling studies using the OZIPR trajectory model and the SAPRC chemical mechanism indicate that formaldehyde is the main ozone precursor in Rio de Janeiro and acetaldehyde is the forth one. 相似文献
906.
Biljana Škrbić Katarzyna Szyrwińska Nataša Đurišić-Mladenović Piotr Nowicki Janina Lulek 《Environment international》2010,36(8):862-872
Principal component analysis (PCA) was applied to a data set containing the levels of indicator polychlorinated biphenyls (PCBs) in human milk of mothers living in the Wielkopolska region, Poland, in order to investigate the information captured in the PCB patterns and to elucidate the relationship between PCB concentrations in milk and donor characteristics. According to the obtained PCA results milk fat content was the most influential factor affecting the PCB levels in milk of the Wielkopolska cohort. The lifestyle data collected from the questionnaire completed by the donors appeared to have no influence on PCB concentrations in breast milk. The score plots revealed the PCB contents of milk were quite low and uniform with a few outliers, without discrimination observed either between the primipareous and secundipareous females or between donors from the urban and rural areas. Comparison of the PCB levels and profiles of human milk from the Wielkopolska region and from various European and Asian locations made by PCA reflected a generally low background exposure and indicated the possible reasons for the outlying of some samples. In order to enhance the chances of observing the relationship between donor habits and PCB levels in breast milk it was suggested that the questionnaire be redesigned to gather information about vegetable product consumption and indoor air exposure. 相似文献
907.
Ana Isabel Miranda Vera Martins Pedro Cascão Jorge Humberto Amorim Joana Valente Richard Tavares Carlos Borrego Oxana Tchepel António Jorge Ferreira Carlos Robalo Cordeiro Domingos Xavier Viegas Luís Mário Ribeiro Luís Paulo Pita 《Environment international》2010,36(7):736-745
Forest fires represent a serious threat to public security in Europe due to the large burned area. Moreover, smoke pollution due to forest fire events is an important public health issue for the communities directly affected, and particularly for the personnel involved in firefighting operations. Aiming to contribute to the scientific knowledge concerning firefighters exposure to forest fires smoke, data of individual exposure to carbon monoxide, nitrogen dioxide, volatile organic compounds, and particulate matter were obtained during experimental field fires for a group of 10 firefighters equipped with portable “in continuum” measuring devices. Measured values are very high exceeding the Occupational Exposure Standard limits, in particular for peak limit thresholds. These are the first measurements and analysis of firefighter's individual exposure to toxic gases and particles in fire smoke experiments in Europe. However, they already indicate that urgent measures to avoid these levels of exposure are needed. 相似文献
908.
Lichens as an integrating tool for monitoring PAH atmospheric deposition: A comparison with soil, air and pine needles 总被引:1,自引:0,他引:1
Sofia Augusto João Matos Cristina Branquinho 《Environmental pollution (Barking, Essex : 1987)》2010,158(2):483-489
The aim of this study was to validate lichens as biomonitors of PAH atmospheric deposition; for that, an inter-comparison between the PAH profile and concentrations intercepted in lichens with those of air, soil and pine needles was performed. The study was conducted in a petro-industrial area and the results showed that PAH profiles in lichens were similar to those of the air and pine needles, but completely different from those of soils. Lichens accumulated higher PAH concentrations when compared to the other environmental compartments and its concentrations were significantly and linearly correlated with concentrations of PAHs in soil; we showed that a translation of the lichen PAHs concentrations into regulatory standards is possible, fulfilling one of the most important requirements of using lichens as biomonitors. With lichens we were then able to characterize the air PAHs profile of urban, petro-industrial and background areas. 相似文献
909.
In the present work, polylactic acid, PLA, samples were degraded by hydrothermal treatment, and then their molecular weights,
crystallinity, surface charges and compositions, were determined, respectively, by using viscometry, 1H NMR, Differential Scanning Calorimetry (DSC), microelectrophoresis and Infra Red spectroscopy methods. The viscometry and
1H NMR data indicate that the molecular weight, of the polymer, decreases after the hydrothermal treatment. However, the crystalline
fractions of the PLA samples, as obtained from the DSC and X-ray data, were not altered after the hydrothermal treatment.
Furthermore, the zeta potential data, as determined by microelectrophoresis, show for both non-degraded and degraded PLA,
an increase of the polymer surface charge density with the pH of the aqueous phase. However, at acidic pH values, the surface
charge density for the degraded PLA was higher as compared to the non degraded one. These differences in surface charge densities
of the PLA samples were confirmed by Infrared study, according to which the spectra of degraded polymer show the appearance
of carboxyl groups occurring at 1,600 cm−1 at the polymer surface. 相似文献
910.
Eduardo González María González-Sanchis Álvaro Cabezas Francisco A. Comín Etienne Muller 《Environmental management》2010,45(4):669-681
The structure of the floodplain forests of the Middle Ebro River (NE Spain) was examined at patch and landscape scales along
a three-step chronosequence defined according to the extent of flow regulation-induced hydrogeomorphic changes, with the ultimate
purpose of producing baseline information to guide through management and restoration plans. At patch scale, a total of 6,891
stems within 39 plots were registered for species, diameter and health status. The stem density, size class distribution,
canopy dieback and mortality were further compared by means of non-parametric tests. At landscape scale, the temporal evolution
of the area occupied by forest stands of different ages in the floodplain along the chronosequence was evaluated using four
sets of aerial photographs dated in 1927, 1957, 1981 and 2003. The within-patch structure of pioneer forests (<25–30 years old) was characterized by dense and healthy populations of pioneer species (Populus nigra, Salix alba and Tamarix spp.), but the area occupied by these forest types has progressively decreased (up to 37%) since the intensification of river
regulation (ca. 1957). In contrast, non-pioneer forests (>25–30 years old) were characterized by declining and sparse P. nigra–S. alba–Tamarix spp. stands, where late-seral species such as Ulmus minor and Fraxinus angustifolia were frequent, but only as small-size stems. At landscape scale, these type of senescent forests have doubled their surface
after river regulation was intensified. Populus alba only appeared in the oldest plots recorded (colonized before 1957), suggesting sexual regeneration failure during the last
five decades, but usually as healthy and dense stands. Based on these findings, measures principally aimed at recovering some
hydrogeomorphic dynamism are recommended to guarantee the self-sustainability of the floodplain forest ecosystem. 相似文献