Atmospheric carbonaceous aerosols over grasslands of central Europe and a Boreal forest

A labour-intensive analytical technique was applied to atmospheric particulate matter samples collected in a German urban/industrial influenced grassland location (Melpitz) and in a Finnish forest area (Hyyti?l?) in order to achieve a detailed chemical speciation of the organic content. The representative nature of the solvent and water-extractable fractions was determined. The organic compounds identified in the solvent extracts are represented by primary compounds with both anthropogenic and biogenic origin, which mainly derive from the vegetation waxes and from petrogenic sources. Secondary products resulting from the oxidation of volatile organic compounds were also detected. The German meadow presented the highest levels of sugars and acidic compounds in the water extracts, whilst polyols were the most abundant class in the Finnish forest. The major compounds of these classes were malic acid, mannitol, arabitol, glucose and sucrose. Levoglucosan was also found in the water extract.     

Hydrocarbons in particulate samples from wildfire events in central Portugal in summer 2010

In summer 2010, twenty eight(14 PM_(2.5)samples plus 14 samples PM_(2.5–10)) smoke samples were collected during wildfires that occurred in central Portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse(PM_(2.5–10)) and fine(PM_(2.5)) smoke samples. The carbonaceous content(elemental and organic carbon) of particulate matter was analysed by a thermal–optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatography into three different classes of organic compounds(aliphatics, polycyclic aromatic hydrocarbons(PAHs) and carbonyl compounds). The organic speciation was performed by gas chromatography–mass spectrometry(GC–MS). Emissions were dominated by the fine particles, which represented around 92% of the PM_(10). A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon(OC/EC)ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between OC and both aliphatic and PAH compounds. Pyrogenic processes, thermal release of biogenic compounds and secondary processing accounted for 97% of the apportioned PM_(2.5)levels.     

Indoor air quality in elementary schools of Lisbon in spring

Analysis of indoor air quality (IAQ) in schools usually reveals higher levels of pollutants than in outdoor environments. The aims of this study are to measure indoor and outdoor concentrations of NO₂, speciated volatile organic compounds (VOCs) and carbonyls at 14 elementary schools in Lisbon, Portugal. The investigation was carried out in May–June 2009. Three of the schools were selected to also measure comfort parameters, such as temperature and relative humidity, carbon dioxide (CO₂), carbon monoxide (CO), total VOCs, and bacterial and fungal colony-forming units per cubic metre. Indoor concentrations of CO₂ in the three main schools indicated inadequate classroom air exchange rates. The indoor/outdoor (I/O) NO₂ ratio ranged between 0.36 and 0.95. At the three main schools, the total bacterial and fungal colony-forming units (CFU) in both indoor and outdoor air were above the advised maximum value of 500 CFU/m³ defined by Portuguese legislation. The aromatic compounds benzene, toluene, ethylbenzene and xylenes, followed by ethers, alcohols and terpenes, were usually the most abundant classes of VOCs. In general, the indoor total VOC concentrations were markedly higher than those observed outdoors. At all locations, indoor aldehyde levels were higher than those observed outdoors, particularly for formaldehyde. The inadequate ventilation observed likely favours accumulation of pollutants with additional indoor sources.     

Assessment of trace metals pollution in estuarine sediments using SEM-AVS and ERM?CERL predictions

In this paper a PSIAC-based multi-parameter fuzzy pattern recognition (MPFPR) model is proposed and applied for classifying and ranking the potential soil erosion (PSE). In this approach, standard value matrix is used to define the membership degrees of each catchment to each class and the feature values are used for alternative ranking. The characteristic of PSE for each class is expressed by linguistic variables. The proposed method is straightforward, easy to understand, very practical, and its results may easily be interpreted. To assess the performance of the model, the results of PSIAC MPFPR and original PSIAC method are interpreted and compared with the observed data. It is shown that the proposed approach reflects the fuzzy nature of the soil erosion more efficiently and is quite robust for application in real world cases.     

Factors influencing survival duration and choice of virgin queens in the stingless bee Melipona quadrifasciata

In Melipona quadrifasciata, about 10 % of the females develop into queens, almost all of which are killed. Occasionally, a new queen replaces or supersedes the mother queen or heads a new colony. We investigated virgin queen fate in queenright and queenless colonies to determine the effects of queen behaviour, body mass, nestmate or non-nestmate status, queenright or queenless colony status, and, when queenless, the effect of the time a colony had been queenless, on survival duration and acceptance. None of 220 virgin queens observed in four observation hives ever attacked another virgin queen nor did any of 88 virgin queens introduced into queenright colonies ever attack the resident queen. A new queen was only accepted in a queenless colony. Factors increasing survival duration and acceptance of virgin queens were to emerge from its cell at 2 h of queenlessness, to hide, and to avoid fights with workers. In this way, a virgin queen was more likely to be available when a colony chooses a new queen, 24-48 h after resident queen removal. Running, walking or resting, antennating or trophallaxis, played little or no role, as did the factors body mass or nestmate. “Queen choice” took about 2 h during which time other virgin queens were still being killed by workers. During this agitated process, the bees congregated around the new queen. She inflated her abdomen and some of the workers deposited a substance on internal nest surfaces including the glass lid of the observation hive.     

Adsorptive and photocatalytic activity of Fe3O4-functionalized multilayer graphene oxide in the treatment of industrial textile wastewater

Environmental Science and Pollution Research - Multilayer graphene oxide (mGO) was synthesized and functionalized via co-precipitation method to produce magnetic Fe3O4-functionalized multilayer...     

Sexual and asexual reproduction of <Emphasis Type="Italic">Coscinasterias</Emphasis><Emphasis Type="Italic">tenuispina</Emphasis> (Echinodermata: Asteroidea) from Rio de Janeiro,Brazil

An intertidal population of the fissiparous sea star Coscinasterias tenuispina (Lamarck, 1816) was sampled over a 1 year period at Ponta de Itaipu, Niterói, Rio de Janeiro. Gonadal indices revealed an annual reproductive cycle. Spawning occurred in the late winter and early spring between August and November. Pyloric caecal indices did not show a clear annual cycle or a reciprocal relationship with gonadal indices. The population appears to be sustained only by fission, as only males were found. Fission occurred throughout the year, but was most frequent in the winter (July, August and September). Incidence of fission was correlated with the occurrence of the extremely low tides during daytime that exposes many specimens to air. Austral winter tides are low by day and high by night, while the austral summer tides are low by night and high by day. The most extreme annual deviation in seawater temperature is about 5°C. Larval recruitment seems to be negligible, since very small individuals were not found.     

Vegetation productivity under climate change depends on landscape complexity in tropical drylands

Mitigation and Adaptation Strategies for Global Change - All Clean Development Mechanism (CDM) projects are designed to contribute to the sustainable development of the host country. Livelihood is...     

Effects of lead exposure on salivary glands of rats: insights into the oxidative biochemistry and glandular morphology

Environmental Science and Pollution Research - This study aimed to investigate the effects of lead (Pb) exposure on parotid and submandibular glands through morphological aspects as well as the...     

Iron recovery from the coarse fraction of basic oxygen furnace sludge. Part I: optimization of acid leaching conditions

Environmental Science and Pollution Research - In this study, a new reuse process of the coarse fraction of basic oxygen furnace (BOF) sludge based on iron recovery by the ferrous sulfate...