Methane production potential from anaerobic digestion of plant biomass residues and food waste as substrates

Journal of Material Cycles and Waste Management - This research aimed to evaluate the production of biogas from anaerobic digestion (AD) using swine manure inoculum associated with different...     

Consumption of low-density polyethylene,polypropylene, and polystyrene materials by larvae of the greater wax moth,Galleria mellonella L. (Lepidoptera,Pyralidae), impacts on their ontogeny

Low-density polyethylene (LDPE), biaxially oriented polypropylene (BOPP), and expanded polystyrene (EXPS) are the most common plastics found in every home of the world, but only ~ 10% enter the recycling chains. Consequently, the study of plastic biodegradation by microorganisms and insects, such as the wax moths, has gained special interest. Galleria mellonella (L.) has been shown to consume single-layered polyethylene and polystyrene, though biological impacts of this consumption have been rarely reported. We evaluated the consumption of different plastics by G. mellonella larvae (L7, mean size: 25–30 mm) and its effect on larval duration, survival, and development. For this, we offered the larvae five diets: single-layered LDPE, EXPS, BOPP, triple-layered polyethylene (SB, for silo-bags), and a control with beeswax. We recorded the state and weight of the materials and the state of larvae until they reached the adult stage. Larvae consumed more PE (both LDPE and SB) and EXPS than BOPP; still, they were able to emerge as adults in all treatments. Larvae that consumed plastics turned into pupal stage faster than those that consumed beeswax, regardless of the type and amount of plastic consumed. This is the first report of wild G. mellonella larvae in Argentina consuming biaxially polypropylene and silo-bags.

     

Sulphur isotope mass balance of dissolved sulphate ion in a freshwater dam reservoir

We show that sulphur isotopic composition can be a useful tool to discriminate between various sources of sulphate and a tool for better understanding of the sulphur cycling and mass balance. Our investigations, carried out in a dam reservoir, demonstrate differences in sulphur biogeochemistry between different seasons, caused by recharge water supply in spring and intensive sulphate reduction in summer. In the riverine-affected part of the reservoir δ³⁴S(SO₄ ²⁻) varied from 4.7 to 5.9‰ in spring, and from 4.1 to 4.6‰ in summer. In the lacustrine-affected part δ³⁴S(SO₄²⁻) varied from 4.0 to 5.0‰ in spring, and from 4.5 to 5.4‰ in summer. Diurnal variations of δ³⁴S(SO₄ ²⁻) were negligible as compared to seasonal variations.     

UVC Inactivation of dsDNA and ssRNA Viruses in Water: UV Fluences and a qPCR-Based Approach to Evaluate Decay on Viral Infectivity

Disinfection by low-pressure monochromatic ultraviolet (UVC) radiation (253.7 nm) became an important technique to sanitize drinking water and also wastewater in tertiary treatments. In order to prevent the transmission of waterborne viral diseases, the analysis of the disinfection kinetics and the quantification of infectious viral pathogens and indicators are highly relevant and need to be addressed. The families Adenoviridae and Polyomaviridae comprise human and animal pathogenic viruses that have been also proposed as indicators of fecal contamination in water and as Microbial Source Tracking tools. While it has been previously suggested that dsDNA viruses may be highly resistant to UVC radiation compared to other viruses or bacteria, no information is available on the stability of polyomavirus toward UV irradiation. Here, the inactivation of dsDNA (HAdV2 and JCPyV) and ssRNA (MS2 bacteriophage) viruses was analyzed at increasing UVC fluences. A minor decay of 2-logs was achieved for both infectious JC polyomaviruses (JCPyV) and human adenoviruses 2 (HAdV2) exposed to a UVC fluence of 1,400 J/m², while a decay of 4-log was observed for MS2 bacteriophages (ssRNA). The present study reveals the high UVC resistance of dsDNA viruses, and the UV fluences needed to efficiently inactivate JCPyV and HAdV2 are predicted. Furthermore, we show that in conjunction with appropriate mathematical models, qPCR data may be used to accurately estimate virus infectivity.     

Quality of basic data and method to identify shape affect richness-altitude relationships in meta-analysis

We compiled 109 species richness-altitude (SRA) relationships in arthropods to test the hypothesis that identification of shape and robustness of pattern are contingent on the selection of studies included in meta-analysis. We used attributes of their sampling design to distinguish three subsets of data according to stringent, intermediate, and lax selection criteria. We tested (1) whether uncertainty over identification of shape increases as the criteria of inclusion of studies relaxes and (2) whether studies that conform to stringent selection criteria show robustness in SRA patterns to variation in method used to identify shape. We identified the shape of each SRA relationship using statistical and visual methods; data sets that suggested several shapes as equally likely were sorted out by consensus. Arthropods suggested multiple forms in the SRA relationship, with predominance of hump-shaped patterns in the stringent subset. Uncertainty over identification of shape increased after application of intermediate and lax selection criteria. The method of analysis interacted with the quality of basic data to influence the relative distribution of patterns. We concluded that the gathering of large quantities of data is insufficient and that critical evaluation of literature is crucial to infer with confidence the general shape of ecological patterns in meta-analysis.     

The key role played by the Augusta basin (southern Italy) in the mercury contamination of the Mediterranean Sea

The Augusta basin, located in SE Sicily (southern Italy), is a semi-enclosed marine area, labelled as a highly contaminated site. The release of mercury into the harbour seawater and its dispersion to the blue water, make the Augusta basin a potential source of anthropogenic pollution for the Mediterranean Sea. A mass balance was implemented to calculate the HgT budget in the Augusta basin. Results suggest that an average of ～0.073 kmol of HgT is released, by diffusion, on a yearly basis, from sediments to the seawater, with a consequent output of 0.162 kmol y(-1) to coastal and offshore waters; this makes the Augusta area an important contributor of mercury to the Mediterranean Sea. Owing to the geographical location of the Augusta basin, its outflowing shelf-waters are immediately intercepted by the surface Atlantic Ionian Stream (AIS) and mixed with the main gyres of the eastern Mediterranean Sea, thus representing a risk for the large-scale marine system.     

Chemical composition, sources, solubility, and transport of aerosol trace elements in a tropical region

Aerosol particle samples (PM10) were collected at urban, industrial and rural sites located in Rio de Janeiro, Brazil, between October 2008 and September 2009. Aerosol samples for each site were analyzed for total and soluble metals, water-soluble ions, carboxylic acids, and water-soluble organic carbon (WSOC). The results showed that the mean PM10 concentrations were 34 μg m(-3); 47 μg m(-3) and 71 μg m(-3) at the rural, urban and industrial sites, respectively. An increase in the average concentration of these particles due to air stagnation was observed during the period from May to September for all sites, and an increase in hospitalization for respiratory problems was also reported. On average, the anions species represented 4 to 14% of total content, while cations species corresponded to 1 to 11% and 7.5% for WSOC. The overall metal content at the industrial site was nearly the double that at the rural site. The concentrations of the studied species are influenced mainly by site location and the specific characteristics present at each site. However, higher concentrations of some species were observed on particular dates and were probably due to biomass burning and African dust events. The acid/aqueous percentiles showed that the most efficiently extracted metals from the aqueous phase were V and Ni (40%), while Al and Fe represented a lower percentage (<3%). Analysis of the aqueous fraction provides important information about the bioavailability of metals that is associated with the inflammatory process in the lungs.     

A new approach of ecologically based life cycle assessment for biological wastewater treatments focused on energy recovery goals

Environmental Science and Pollution Research - The energy potential of high-organic loaded agro-industrial effluents receiving biological treatment is often neglected, particularly in emergent...