Sugarcane straw management for bioenergy: effects of global warming on greenhouse gas emissions and soil carbon storage

Mitigation and Adaptation Strategies for Global Change - Global warming can intensify the soil organic matter (SOM) turnover, damaging soil health. Crop residues left on the soil are important to...     

Predominance of alcohol and illicit drugs among traffic accidents fatalities in an urban area of Brazil

Objective: The objective of this study was to determine the prevalence of alcohol and illicit drug use among victims of fatal traffic accidents in the Metropolitan Region of Vitória, Brazil, during the period 2011–2012.

Methods: Blood samples were collected and analyzed for the presence of drugs from 391 deceased victims of traffic crashes that occurred in the Metropolitan Region of Vitória, Brazil. The victims included drivers, passengers, and pedestrians. Sociodemographic variables such as age, gender, day of the week, and period of the year in which the accidents occurred were recorded. The analyses were performed by a gas chromatography–flame ionization method for alcohol and by a gas chromatography–mass spectrometry for amphetamines, cocaine, and cannabis.

Results: The results showed that 44.8% (n = 175) of all cases were positive for alcohol and/or illicit drugs. The detection of alcohol and/or drugs was more frequent in young males, aged 17 to 34, whose samples were positive in 46.8% of cases. Small differences among drivers, passengers, and pedestrians were observed (drivers = 45.9%, passengers = 46.4%, and pedestrians = 45.6%). In general, the most prevalent drug was alcohol, with 141 positive cases (36.1%), followed by cocaine, with 47 positive cases (12%). Amphetamines and cannabis had positivity rates of 4.1 and 4.3%, with 16 and 17 positive cases, respectively. The combined use of alcohol and other drugs was found in 36 cases (9.2%). Crack cocaine use was observed in 27.7% of the positive cases for cocaine.

Conclusions: For the effective reduction of traffic accidents related to driving under influence of drugs (DUID), we suggest the intensification of enforcement actions against the use of alcohol by drivers, the definition of which illicit drugs should be surveyed, as well the cutoff values, the promotion of changing legislation to oblige drivers to provide samples for toxicological testing, and the establishment of public information programs and specific actions aimed at young drivers to promote behavioral changes.     

Flow cytometric characterization of bacterial abundance and physiological status in a nitrifying-denitrifying activated sludge system treating landfill leachate

Environmental Science and Pollution Research - Flow cytometry has recently been presented as a research tool in the assessment of the viability/activity of activated sludge from municipal...     

Embryonic,larval, and post-metamorphic development of the sea urchin <Emphasis Type="Italic">Cassidulus mitis</Emphasis> (Echinoidea; Cassiduloida): an endemic brooding species from Rio de Janeiro,Brazil

Cassiduloids are currently rare irregular echinoids with a highly conserved adult morphology. Aristotle’s lantern is present only during the post-metamorphic stage, and little is known about the early development of species in this group. Cassidulus mitis produces eggs of about 375 μm in diameter, lecithotrophic larvae with four reduced arms with skeletal fenestrated rods, cilia along the body surface, and a ciliated band on arms and lobes. Offspring is brooded among the female spines from embryo to settler’s stage. The echinopluteus larval stage is reached 6 days after fertilization, and the settler’s stage is formed at the age of 17 days. Aristotle’s lantern appears around the thirteenth day of development. The lantern is well developed and functional in settlers. It remains until at least 62 days after fertilization and can be used to acquire food from the environment. The early development of C. mitis is unusual concerning features of typical lecithotrophic larvae (such as reduced arms), but retains some features of planktotrophic larvae (such as skeletal rods and a ciliated band). Regarding egg size, early development in C. mitis seems to be transitioning from facultative lecithotrophic to typical obligate lecithotrophic pattern in echinoid larval evolution.     

Selenite resistant rhizobacteria stimulate SeO3 2– phytoextraction by Brassica juncea in bioaugmented water-filtering artificial beds

Background, aim, and scope  

Selenium is a trace metalloid of global environmental concern. The boundary among its essentiality, deficiency, and toxicity is narrow and mainly depends on the chemical forms and concentrations in which this element occurs. Different plant species—including Brassica juncea—have been shown to play a significant role in Se removal from soil as well as water bodies. Furthermore, the interactions between such plants, showing natural capabilities of metal uptake and their rhizospheric microbial communities, might be exploited to increase both Se scavenging and vegetable biomass production in order to improve the whole phytoextraction efficiency. The aim of the present study was to evaluate the capability of selenite removal of B. juncea grown in hydroponic conditions on artificially spiked effluents. To optimize phytoextraction efficiency, interactions between B. juncea and rhizobacteria were designedly elicited.     

Assessment of the allelopathic effect of leaf and seed extracts of Canavalia ensiformis as postemergent bioherbicides: A green alternative for sustainable agriculture

The herbicidal potential of aqueous extracts prepared from leaves and seeds of Canavalia ensiformis was tested by applying them postemergence to the crop weeds Ipomoea grandifolia and Commelina benghalensis. Considering the possible objective of using this bioherbicide on soybean fields, the extracts were also tested for deleterious effects on both transgenic and conventional soybean (Glycine max). In addition, the concentrations of four phenolic compounds and alkaloids with allelopathic properties in these extracts were estimated by high-performance liquid chromatography. The seed extract at concentrations of 25 g L^?1 and 50 g L^?1 was the most efficient postemergent bioherbicide. By applying these extracts, the development of the weed seed was progressively hindered until no recovery was observed. The application of 3.5 mL of crude extract on a plant that takes 30 days after germination of the seed to develop is sufficient for full control of the species within 5 days. Since both Ipomoea grandifolia and Commelina benghalensis are broadleaf dicotyledons, it is possible that other species with these characteristics can also be controlled or suffer the same effects under the action of the seed extract, if the same volume and mode of application are used. The selectivity of the treatments with 25 g L^?1 and 50 g L^?1 was assessed on transgenic and conventional cultivars. The treatments did not visibly affect the soybean cultivars, which developed normally during the observation period that continued up to 15 days after the death of the weeds.     

Toxicity of two types of silver nanoparticles to aquatic crustaceans Daphnia magna and Thamnocephalus platyurus

Although silver nanoparticles (NPs) are increasingly used in various consumer products and produced in industrial scale, information on harmful effects of nanosilver to environmentally relevant organisms is still scarce. This paper studies the adverse effects of silver NPs to two aquatic crustaceans, Daphnia magna and Thamnocephalus platyurus. For that, silver NPs were synthesized where Ag is covalently attached to poly(vinylpyrrolidone) (PVP). In parallel, the toxicity of collargol (protein-coated nanosilver) and AgNO₃ was analyzed. Both types of silver NPs were highly toxic to both crustaceans: the EC50 values in artificial freshwater were 15–17 ppb for D. magna and 20–27 ppb for T. platyurus. The natural water (five different waters with dissolved organic carbon from 5 to 35 mg C/L were studied) mitigated the toxic effect of studied silver compounds up to 8-fold compared with artificial freshwater. The toxicity of silver NPs in all test media was up to 10-fold lower than that of soluble silver salt, AgNO₃. The pattern of the toxic response of both crustacean species to the silver compounds was almost similar in artificial freshwater and in natural waters. The chronic 21-day toxicity of silver NPs to D. magna in natural water was at the part-per-billion level, and adult mortality was more sensitive toxicity test endpoint than the reproduction (the number of offspring per adult).     

Accelerated carbonation treatment of industrial wastes

The disposal of industrial waste presents major logistical, financial and environmental issues. Technologies that can reduce the hazardous properties of wastes are urgently required. In the present work, a number of industrial wastes arising from the cement, metallurgical, paper, waste disposal and energy industries were treated with accelerated carbonation. In this process carbonation was effected by exposing the waste to pure carbon dioxide gas. The paper and cement wastes chemically combined with up to 25% by weight of gas. The reactivity of the wastes to carbon dioxide was controlled by their constituent minerals, and not by their elemental composition, as previously postulated. Similarly, microstructural alteration upon carbonation was primarily influenced by mineralogy. Many of the thermal wastes tested were classified as hazardous, based upon regulated metal content and pH. Treatment by accelerated carbonation reduced the leaching of certain metals, aiding the disposal of many as stable non-reactive wastes. Significant volumes of carbon dioxide were sequestrated into the accelerated carbonated treated wastes.