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911.
Beniamino Gioli Maria F. Carfora Vincenzo Magliulo Maria C. Metallo Attilio A. Poli Piero Toscano Franco Miglietta 《Environmental monitoring and assessment》2014,186(4):2053-2066
Aircraft measurements were used to estimate the CO2 emission rates of the city of Rome, assessed against high-resolution inventorial data. Three experimental flights were made, composed of vertical soundings to measure Planetary Boundary Layer (PBL) properties, and circular horizontal transects at various altitudes around the city area. City level emissions and associated uncertainties were computed by means of mass budgeting techniques, obtaining a positive net CO2 flux of 14.7?±?4.5, 2.5?±?1.2, and 10.3?±?1.2 μmol m?2 s?1 for the three flights. Inventorial CO2 fluxes at the time of flights were computed by means of spatial and temporal disaggregation of the gross emission inventory, at 10.9?±?2.5, 9.6?±?1.3, and 17.4?±?9.6 μmol m?2 s?1. The largest differences between the two dataset are associated with a greater variability of wind speed and direction in the boundary layer during measurements. Uncertainty partitioned into components related to horizontal boundary flows and top surface flow, revealed that the latter dominates total uncertainty in the presence of a wide variability of CO2 concentration in the free troposphere (up to 7 ppm), while it is a minor term with uniform tropospheric concentrations in the study area (within 2 ppm). Overall, we demonstrate how small aircraft may provide city level emission measurements that may integrate and validate emission inventories. Optimal atmospheric conditions and measurement strategies for the deployment of aircraft experimental flights are finally discussed. 相似文献
912.
Corona P Agrimi M Baffetta F Barbati A Chiriacò MV Fattorini L Pompei E Valentini R Mattioli W 《Environmental monitoring and assessment》2012,184(3):1409-1422
Urban areas are continuously expanding today, extending their influence on an increasingly large proportion of woods and trees
located in or nearby urban and urbanizing areas, the so-called urban forests. Although these forests have the potential for
significantly improving the quality the urban environment and the well-being of the urban population, data to quantify the
extent and characteristics of urban forests are still lacking or fragmentary on a large scale. In this regard, an expansion
of the domain of multipurpose forest inventories like National Forest Inventories (NFIs) towards urban forests would be required.
To this end, it would be convenient to exploit the same sampling scheme applied in NFIs to assess the basic features of urban
forests. This paper considers approximately unbiased estimators of abundance and coverage of urban forests, together with
estimators of the corresponding variances, which can be achieved from the first phase of most large-scale forest inventories.
A simulation study is carried out in order to check the performance of the considered estimators under various situations
involving the spatial distribution of the urban forests over the study area. An application is worked out on the data from
the Italian NFI. 相似文献
913.
Martins LD da Silva Júnior CR Solci MC Pinto JP Souza DZ Vasconcellos P Guarieiro AL Guarieiro LL Sousa ET de Andrade JB 《Environmental monitoring and assessment》2012,184(5):2663-2676
In this study, particulate matter (PM) were characterized from a place impacted by heavy-duty vehicles (Bus Station) fuelled
with diesel/biodiesel fuel blend (B3) in the city of Londrina, Brazil. Sixteen priority polycyclic aromatic hydrocarbons (PAH)
concentrations were analyzed in the samples by their association with atmospheric PM, mass size distributions and major ions
(fluorite, chloride, bromide, nitrate, phosphate, sulfate, nitrite, oxalate; fumarate, formate, succinate and acetate; lithium,
sodium, potassium, magnesium, calcium and ammonium). Results indicate that major ions represented 21.2% particulate matter
mass. Nitrate, sulfate, and ammonium, respectively, presented the highest concentration levels, indicating that biodiesel
may also be a significant source for these ions, especially nitrate. Dibenzo[a,h]anthracene and indeno[1,2,3,-cd]pyrene were the main PAH found, and a higher fraction of PAH particles was found in diameters lower than 0.25 μm in Londrina bus station. The fine and ultrafine particles were dominant among the PM evaluated, suggesting that biodiesel
decreases the total PAH emission. However, it does also increase the fraction of fine and ultrafine particles when compared
to diesel. 相似文献
914.
IA Fioravante B Albergaria TS Teodoro SM Starling Magalhães F Barbosa R Augusti 《Journal of environmental monitoring : JEM》2012,14(9):2362-2366
An unprecedented investigation dealing with the removal of 17α-ethinylestradiol (EE2, a contraceptive hormone) by the cyanobacteria Microcystis novacekii (a species that is abundant and easily accessible in Brazilian lakes) from a sterile WC medium is described herein. The results indicated that whereas EE2 experienced insignificant spontaneous degradation, Microcystis novacekii was capable of removing ca. 65% of the hormone from the culture medium. Furthermore, no metabolites were detected at the concentration levels evaluated (0.10 to 0.17 mg L(-1)) as verified by the use of GC-MS, a quite sensitive analytical technique, and adequate pre-concentration procedures (SPME and liquid extraction). Elucidative experiments, including an appropriate cell lyses procedure, indicated that EE2 was likely accumulated within the cells (bioaccumulation) rather than adsorbed on the cellular membrane (biosorption). Moreover, the intra- and extracellular contents of EE2 were shown to be roughly complementary. Finally, the species was found to be highly tolerant to the hormone as its growth rates were higher in the test than in the control experiments. All these findings, therefore, point to the use of Microcystis novacekii as a potential agent to treat effluents contaminated with EE2. 相似文献
915.
916.
Most agronomic situations involve a sequence of herbicide, fungicide, and insecticide application. On the other hand, use
of pesticidal combinations has become a standard practice in the production of many agricultural crops. One of the most important
processes influencing the behavior of a pesticide in the environment is its degradation in soil. It is known that due to several
pesticide applications in one vegetation season, the pesticide may be present in mixtures with other pesticides or xenobiotics
in soil. This study examines the role which a mixture of chemicals plays in pesticide degradation. The influence of other
pesticides on the rate of pendimethalin (PDM) degradation in soil was measured in controlled conditions. Mixtures of PDM with
mancozeb or mancozeb and thiamethoxam significantly influenced the degradation of pendimethalin under controlled conditions.
The second type of mixtures, with metribuzin or thiamethoxam, did not affect the behavior of pendimethalin in soil. Also,
we determined the influence of water content on the rate of pendimethalin degradation alone in two soils and compared it to
the rate in three pesticide mixtures. We compared two equations to evaluate the predictors of the rate of herbicide dissipation
in soil: the first-order kinetic and the non-linear empirical models. We used the non-linear empirical model assuming that
the degradation rate of a herbicide in soil is proportional to the difference of the observed concentration of herbicide in
soil at time and concentration of herbicide in the last day of measurement. 相似文献
917.
Maria Aparecida Macêdo Silva Gilmara Fernandes Eça Danielle Felix Santos Alonso Góes Guimarães Michelle Coêlho Lima Marcelo Friederichs Landim de Souza 《Environmental monitoring and assessment》2013,185(7):5387-5399
Sampling was conducted monthly during a transition period between the dry and rainy seasons in order to evaluate the effectiveness of a municipal sewage treatment plant (STP) in eutrophication control. STP effluent and fluvial input data were also estimated. In the dry period, high concentrations of nutrients, chlorophyll a (up to 360 μg?L?1), and anoxia in bottom waters were observed in the upper portion of the estuary. Nitrate was scarce during the dry months, although high concentrations were observed at the river sources and the upper estuary. The N:P and Si:P molar ratios were usually below 16:1, and the Si:N ratio was higher than 1:1. The fluvial inputs were a greater source of nutrients to the estuary than the STP, but nutrient loading by these effluents were also important in contributing to the eutrophication of the upper estuarine zone, especially in the dry season when symptoms were more intense. 相似文献
918.
Lígia Maria Crubelati Bulla Julio Cesar Polonio Ana Luiza de Brito Portela-Castro Vanessa Kava João Lúcio Azevedo João Alencar Pamphile 《Environmental monitoring and assessment》2017,189(2):88
The current study investigates the potential for discolouration and degradation of Reactive Blue 19 and Reactive Black 5 textile dyes by endophytic fungi Phlebia sp. and Paecilomyces formosus as well as the potential cytotoxicity of products or by-products generated by the treatments in fish erythrocytes. It was observed at 30 days that both endophytes showed biodegradation activity with 0.1 g mL?1 of dyes. P. formosus showed highest extracellular and intracellular protein content levels after the 15th day, and Phlebia sp. stands out for production of extracellular laccase, indicating that this enzyme may be associated with the decolouration capacity. The dyes showed toxic effects in fishes at 0.01 g mL?1 concentration, resulting in the appearance of micronuclei in erythrocyte cells. When degraded dyes treated by endophytes were tested, the frequency of micronuclei reduced approximately 20%, indicating the effectiveness of these endophytic in the treatment of textile dyes with less environmental impact, thus indicating a potential for application of these fungi in bioremediation process. 相似文献
919.
Aline A. Becaro Maria Célia Siqueira Fernanda C. Puti Marcia Regina de Moura Daniel S. Correa José Manoel Marconcini Luiz H. C. Mattoso Marcos David Ferreira 《Environmental monitoring and assessment》2017,189(7):352
Several mutagenic agents may be present in substances released in the environment, which may cause serious environmental impacts. Among these substances, there is a special concern regarding the widespread use of silver nanoparticles (AgNP) in several products due to their widely known bactericidal properties, including in the medical field and the food industry (e.g., active packaging). The assessment of the effects of AgNP released in the environment, having different concentrations, sizes, and being associated or not to other types of materials, including polymers, is therefore essential. In this research, the objective was to evaluate the genotoxic and cytotoxic effects of AgNP (size range between 2 and 8 nm) on root meristematic cells of Allium cepa (A. cepa). Tests were carried out in the presence of colloidal solution of AgNP and AgNP mixed with carboxymethylcellulose (CMC), using distinct concentrations of AgNP. As a result, when compared to control samples, AgNP induced a mitotic index decrease and an increase of chromosomal aberration number for two studied concentrations. When AgNP was in the presence of CMC, no cytotoxic potential was verified, but only the genotoxic potential for AgNP dispersion having concentration of 12.4 ppm. 相似文献
920.
João Marcelo de Castro e Sousa Ana Paula Peron Louridânya da Silva e Sousa Mércia de Moura Holanda Ataíde de Macedo Vieira Lima Vitor Alves de Oliveira Felipe Cavalcanti Carneiro da Silva Leonardo Henrique Guedes de Morais Lima Leomá Albuquerque Matos Sandra Maria Mendes de Moura Dantas Raí Pablo Sousa de Aguiar Muhammad Torequl Islam Ana Amélia de Carvalho Melo-Cavalcante Cláudia Costa Bonecker Horácio Ferreira Júlio Junior 《Environmental monitoring and assessment》2017,189(6):301
In general, tropical rivers have a great impact on human activities. Bioaccumulation of toxins is a worldwide problem nowadays and has been, historically, overlooked by the supervisory authorities. This study evaluated cytogenotoxic effects of Guaribas river (a Brazilian river) water during dry and rainy seasons of 2014 by using the Allium cepa test system. The toxicogenetic variables, including root growth, mitotic index, and chromosomal aberrations, were analyzed in meristematic cells of A. cepa exposed to water samples taken from the up-, within, and downstream of the city Picos (state: Piauí). The physical-chemical parameters were also analyzed to explain water quality and possible anthropogenic action. Additionally, the presence of heavy metals was also analyzed to explain water quality and possible damaging effects on eukaryotic cells. The results suggest that the river water exerted cytotoxic, mutagenic, and genotoxic effects, regardless of the seasons. In addition, Guaribas river presented physico-chemical values outside the Brazilian laws, which can be a characteristic of human pollution (domestic sewage, industrial, and local agriculture). The genetic damage was positively correlated with higher levels of heavy metals. The pollution of the Guaribas river water may link to the chemical contamination, including the action of heavy metals and their impacts on genetic instability in the aquatic ecosystem. In conclusion, necessary steps should be taken into account for further toxicogenetic studies of the Guaribas river water, as it has an influence in human health of the same region of Brazil. 相似文献