PM2.5 aerosols collected in the Antarctic Peninsula with a solar powered sampler during austral summer periods

Collection of PM2.5 particles was carried out in Antarctica in the summer periods of years 2006 and 2007 using solar panels to operate the sampling unit. The unit was installed 2.5 km from the B. O'Higgins Chilean base to avoid possible air contamination from oil or gas burning electric power stations. The aerosols were analyzed by XRF identifying twenty elements between Na and Sr. Results showed the presence of elements of typical Earth crust and seawater origins. In addition, considerable amounts of non-sea sulfur together with traces of Pb and Se from probable long distant anthropogenic activities were observed.     

An approach for determining air pollution monitoring sites

EC Directive 2008/50/CE on ambient air quality and cleaner air for Europe specifies the obligations of Member States regarding fixed measurements of atmospheric pollutants in areas where maximum concentration levels exceed the lower assessment threshold. However, indications as to the siting of atmospheric monitoring stations are less precise and sometimes confusing. Campaigns to measure benzene and other volatile organic compounds in Murcia in 2007 and 2008 revealed that the areas where measurements coincided with the mean concentration for the whole city were always practically the same. Consequently, we propose a method for siting atmospheric monitoring stations in cities for which emission sources remain steady throughout the year, as is the case for cities in most southern European countries, where the most important emission source is traffic. The method is particularly useful for towns in which only one fixed measuring point is compulsory and should help local authorities in making correct decisions in this context.     

Health impact assessment of air pollutants during the COVID-19 pandemic in a Brazilian metropolis

Environmental Science and Pollution Research - Studies around the world have revealed reduced levels of atmospheric particulate matter in periods of greatest human mobility restriction to contain...     

Pollutant Transport During a Regional O3 Episode in the Mid-Atlantic States

ABSTRACT

Ozone (O₃) concentrations in the Baltimore-Washington (B-W) metropolitan area frequently exceed the National Ambient Air Quality Standard (NAAQS) in the summer months. The most extreme O₃ events occur in multi-day high O₃ episodes.¹ These events can be regional in scale, with O₃ concentrations exceeding the NAAQS at numerous locations along the eastern U.S. seaboard, and are typically associated with slow-moving or stagnant high pressure systems.^2-5 In the B-W region, the most extreme events typically occur with surface high pressure overhead or just west of the region and an upper air high-pressure area (ridge) to the west or northwest.¹ Besides providing conditions conducive to local O₃ production (subsidence and strong low-level inversions, weak horizontal winds, little cloud cover), this weather pattern may also result in transport of O₃ and its precursors from heavily industrialized areas west and north of the B-W region. In this paper, observations and back trajectories made during the severe regional O₃ event of July 12-15, 1995, are used to confirm the hypothesis that significant regional-scale transport of O₃ and its precursors occur during extreme O₃ events of the standard type in the B-W area.     

A simplified matrix of environmental impacts to support an intervention program in a small-scale mining site

This paper describes a tool developed to evaluate environmental risks at a Brazilian artisanal small-scale gold mining site. The tool consists of a matrix used to determine the relevance of such risks through the classification of mining activities according to the likelihood that they may cause environmental impacts. The language and method are very simple, and thus appropriate for local stakeholders. It ensures their participation when developing a plan of action for intervention and training. When applied to a pilot site in the Brazilian Amazon, the matrix revealed the variables that pose higher environmental risks. These activities were subsequently addressed in a training program to promote better practices. As a result, the mining activities were improved by 28.8% when comparing compliance to environmental requisites before and after the training program. Specifically, the training program resulted in improved gold recovery, and reduced environmental and health impacts.     

Avoiding over-implementation of agri-environmental schemes for steppe bird conservation: A species-focused proposal based on expert criteria

This study presents an assessment, resulting from consultation with experts in steppe-bird conservation (scientists, officers and conservationists) using the Delphi method, of a broad range of agri-environmental measures (AEMs) which have been applied in agricultural areas in Spain, with particular reference to four threatened steppe bird species. The measures which experts have valued most highly relate to the maintenance of fallow land, the prohibition of agrochemicals and the suspension of certain agricultural practices when the species are nesting. Other AEMs which have frequently been mentioned as beneficial for steppe birds, including the maintenance of straw-mulched fallows and the abandonment of farmland, were rejected by the experts. The assessment showed a high degree of consensus between experts, although differences between the four studied species were detected. Delphi assessment indicated that different birds need different AEMs. In addition, expert evaluation showed that different AEMs can cause the same effect on the target species, which could generate an over-implementation of measures. Finally, we evaluated the financial implementation of the AEMs selected by the Delphi using a Special Protection Area for birds (SPA) in the Madrid region as a case study. All the hypothetical scenarios used yielded assumable costs, oscillating between 1 and 2 times the current AEMs expenditure. In conclusion, in extensive agrarian systems with already high conservation merits, the implementation of AEMS could be improved using species-specific assessments, thus avoiding over-implementation and improving the fit between costs and benefits for conservation.     

Relationships between fecal indicators and pathogenic microorganisms in a tropical lagoon in Rio de Janeiro, Brazil

Rodrigo de Freitas Lagoon is an urban ecosystem undergoing accelerated degradation, therefore selected as a model for microbiological quality studies of tropical lagoons. The aim of this study was to evaluate the abundance and the spatial distribution of fecal pollution indicators and pathogenic microorganisms in the lagoon. The relationships between microbial groups and abiotic measurements were also determined to evaluate the influence of environmental conditions on bacterial distribution and to identify the capability of coliforms and Enterococcus to predict the occurrence of Vibrio, Staphylococcus aureus, and Salmonella. Surface water samples were collected monthly, from December 1999 to October 2000. Analyses were performed by traditional culture techniques. A uniform spatial distribution was observed for all bacterial groups. The fecal pollution indicators occurred in low abundances while potentially pathogenic microorganisms were consistently found. Therefore, our study supported the use of counts of coliforms and Enterococcus to indicate only recent fecal contamination.     

The effects of plant distribution and frugivore density on the scale and shape of dispersal kernels

For many plant species, seed dispersal is one of the most important spatial demographic processes. We used a diffusion approximation and a spatially explicit simulation model to explore the mechanisms generating seed dispersal kernels for plants dispersed by frugivores. The simulation model combined simple movement and foraging rules with seed gut passage time, plant distribution, and fruit production. A simulation experiment using plant spatial aggregation and frugivore density as factors showed that seed dispersal scale was largely determined by the degree of plant aggregation, whereas kernel shape was mostly dominated by frugivore density. Kernel shapes ranged from fat tailed to thin tailed, but most shapes were between an exponential and that of the solution of a diffusion equation. The proportion of dispersal kernels with fat tails was highest for landscapes with clumped plant distributions and increased with increasing number of dispersers. The diffusion model provides a basis for models including more behavioral details but can also be used to approximate dispersal kernels once a diffusion rate is estimated from animal movement data. Our results suggest that important characteristics of dispersal kernels will depend on the spatial pattern of plant distribution and on disperser density when frugivores mediate seed dispersal.     

First fossil evidence of an “interglacial refugium” in the Pyrenean region

A refugium is generally understood as an area where temperate species survive cold periods, such as the Iberian, Italian, or Balkan Peninsulas in Europe. Strictly speaking, this definition refers to what is known as a glacial refugium. However, there are various types of lesser-known refugia such as the interglacial refugium, which denotes a mountainous region at low latitudes, such as the Pyrenees, where species adapted to the cold survive during interstadial periods. The small-vertebrate association from the sequence of Cova Colomera, which is located on the southern face of the Pyrenees and contains the final cold spell of the Late Pleistocene and the beginnings of the temperate period in which we currently find ourselves (the Holocene), could constitute the first fossil evidence of such an interglacial refugium, thus providing new paleoecological data on the phenomenon.