Sub-tropical urban environment affecting content and composition of non-structural carbohydrates of Lolium multiflorum ssp. italicum cv. Lema

This study analyzed the relationship between environmental factors, especially air pollution and climatic conditions, and non-structural carbohydrates (NSC) in plants of Lolium multiflorum exposed during 10 consecutive periods of 28 days at a polluted site (Congonhas) and at a reference site in São Paulo city (Brazil). After exposure, NSC composition and leaf concentrations of Al, Fe, Cu, Zn, Pb and Cd were measured. The seasonal pattern of NSC accumulation was quite similar in both sites, but plants at Congonhas showed higher concentrations of these compounds, especially fructans of low and medium degree of polymerization. Regression analysis showed that NSC in plants growing at the polluted site were explained by variations on temperature and leaf concentration of Fe (positive effect), as well as relative humidity and particulate material (negative effect). NSC in the standardized grass culture, in addition to heavy metal accumulation, may indicate stressing conditions in a sub-tropical polluted environment.     

Recovery of PET from packaging plastics mixtures by wet shaking table

Recycling requires the separation of materials appearing in a mass of wastes of heterogeneous composition and characteristics, into single, almost pure, component/material flows. The separation of materials (e.g., some types of plastics) with similar physical properties (e.g., specific gravity) is often accomplished by human sorting. This is the case of the separation of packaging plastics in municipal solid wastes (MSW). The low cost of virgin plastics and low value of recycled plastics necessitate the utilization of low cost techniques and processes in the recycling of packaging plastics. An experimental study was conducted to evaluate the feasibility of production of a PET product, cleaned from PVC and PS, using a wet shaking table. The wet shaking table is an environmentally friendly process, widely used to separate minerals, which has low capital and operational costs. Some operational variables of the equipment, as well as different feed characteristics, were considered. The results show that the separation of these plastics is feasible although, similarly to the mineral field, in somewhat complex flow sheets.     

Artisanal fisheries of the Itaparica reservoir,São Francisco River,Brazil: socioeconomic profile,environmental dynamics,and management recommendations

Currently, artisanal fisheries in fresh water reservoirs have been losing ground to commercial fish farming and a great deal of fishery resources are being threatened by human interventions, such as reservoir management and increasing net-cage aquaculture. This study aims to understand the impacts of environmental changes on fishery resources and analyse the migratory fish breeding season as a missing link for fishery management in the semi-arid area of the São Francisco River Basin. Among the 870 fishermen operating in the Pernambuco part of the Itaparica Reservoir, 10% were interviewed and affirmed that fish stocks have been compromised due to the closed fishing period’s incoherence, exotic species insertion, and changes to the river flow caused by reservoir construction and operation. A significant correlation was observed between the Reproductive Activity Index (RAI) and precipitation (p?=?0.745) as well as between the RAI and the river’s flow (p?=??0.909). This shows how important it is to consider both the semi-arid climate setting and reservoir operation in determining the closed period which should safeguard fish reproduction. Monitoring the fish reproduction period and research on the reproductive biology of native fish species is needed in the São Francisco River Basin’s different stretches in order to guarantee valuable fish stocks and fisheries maintenance. Integrated action between the fish resource users, civil society, and federal bodies/agencies is essential in order to mitigate impacts and improve fish production systems, not only in Brazil, but in other regions experiencing a similar scenario.     

Biogas from poultry waste—production and energy potential

The objective of this study was to evaluate the effect of heat treatment on poultry litter with different levels of reutilisation for potential generation of biogas in experimental biodigesters. Chicken litter used was obtained from two small-scale poultry houses where 14 birds m^?2 were housed for a period of 42 days per cycle. Litter from aviary 1 received no heat treatment while each batch of litter produced from aviary 2 underwent a fermentation process. For each batch taken, two biodigesters were set for each aviary, with hydraulic retention time of 35 days. The efficiency of the biodigestion process was evaluated by biogas production in relation to total solids (TS) added, as well as the potential for power generation. Quantified volumes ranged from 8.9 to 41.1 L of biogas for aviary 1, and 6.7 to 33.9 L of biogas for aviary 2, with the sixth bed reused from both aviaries registering the largest biogas potential. Average potential biogas in m³ kg^?1 of TS added were 0.022 to 0.034 for aviary 1 and 0.015 to 0.022 for aviary 2. Energy values ??of biogas produced were calculated based on calorific value and ranged from 0.06 to 0.33 kWh for chicken litter without fermentation and from 0.05 to 0.27 kWh for chicken litter with fermentation. It was concluded that the re-use of poultry litter resulted in an increase in biogas production, and the use of fermentation in the microbiological treatment of poultry litter seems to have negatively influenced production of biogas.     

A novel holistic framework for genetic‐based captive‐breeding and reintroduction programs

Research in reintroduction biology has provided a greater understanding of the often limited success of species reintroductions and highlighted the need for scientifically rigorous approaches in reintroduction programs. We examined the recent genetic‐based captive‐breeding and reintroduction literature to showcase the underuse of the genetic data gathered. We devised a framework that takes full advantage of the genetic data through assessment of the genetic makeup of populations before (past component of the framework), during (present component), and after (future component) captive‐breeding and reintroduction events to understand their conservation potential and maximize their success. We empirically applied our framework to two small fishes: Yarra pygmy perch (Nannoperca obscura) and southern pygmy perch (Nannoperca australis). Each of these species has a locally adapted and geographically isolated lineage that is endemic to the highly threatened lower Murray–Darling Basin in Australia. These two populations were rescued during Australia's recent decade‐long Millennium Drought, when their persistence became entirely dependent on captive‐breeding and subsequent reintroduction efforts. Using historical demographic analyses, we found differences and similarities between the species in the genetic impacts of past natural and anthropogenic events that occurred in situ, such as European settlement (past component). Subsequently, successful maintenance of genetic diversity in captivity—despite skewed brooder contribution to offspring—was achieved through carefully managed genetic‐based breeding (present component). Finally, genetic monitoring revealed the survival and recruitment of released captive‐bred offspring in the wild (future component). Our holistic framework often requires no additional data collection to that typically gathered in genetic‐based breeding programs, is applicable to a wide range of species, advances the genetic considerations of reintroduction programs, and is expected to improve with the use of next‐generation sequencing technology.     

Americium adsorption on the surface of macrophytic algae

Data are presented on the rates at which americium (Am) deposits upon blade surfaces of three benthic algal species (Ulva rigida, Fucus vesiculosus and Gigartina stellata) following short-term exposures (1–6 h). Am is taken up in direct proportion to the ambient radionuclide concentration in sea water. Uptake by the green alga was 3 to 5 times greater than that for the brown and red species. Experimental evidence indicated that Am accumulation is a passive process and that adsorption takes place mainly on the thin outer organic coating of the seaweed. The Am transport coefficients (0·9–4·1 × 10?⁵ Bq cm?² s?¹ per Bq ml?¹ sea water) are quite similar to that previously found for the naturally occurring α-emitter ²¹⁰Po, but are an order of magnitude lower than a plutonium transport coefficient reported in the literature. Release of labelled extracellular products associated with the algal surface coating is considered to be responsible for the rapid loss of Am observed previously in macroalgae and may in fact serve as a mechanism for transferring Am to filter feeding zooplankton.     

Biokinetics of plutonium,americium and californium in the marine isopod Cirolana borealis,with observations on its feeding and molting behavior

In a series of laboratory experiments carried out during 1982, the biokinetics of ²³⁷Pu (IV), ²³⁷Pu (V), ²⁴¹Am (III), and ²⁵²Cf (III) were studied in the benthic marine isopod Cirolana borealis Lilljeb. Following a 3 wk exposure to labelled seawater, isopods reached non-equilibrium concentration factors of 52±15, 54±12, 176±14, and 185±53 for Pu (IV), Pu (V), Am and Cf, respectively. Uptake of these radionuclides occurred to a great extent by surface adsorption, with the major fraction of the accumulated radionuclides being associated with exoskeleton and lesser percentages located in gut, digestive gland, muscle and haemolymph. The pattern of radiotracer depuration was in all cases biphasic, with the long-lived retention compartment retaining the largest fraction of whole-body radioactivity. Biological half-lives for radionuclide turnover in the long-lived compartment were 60±3 d, 87±5 d, 261±12 d and 288±60 d for Pu (IV), Pu (V), Am and Cf, respectively. Examination of radionuclide distribution among tissues following longterm depuration showed that the radionuclides were eliminated from internal tissues more rapidly than from the exoskeleton. Uptake and depuration studies indicated that the biokinetics of americium and californium were similar to each other, but that they differed significantly from those of oxidized and reduced plutonium. In general, these experimental results support previous reports that americium and californium are more bioavailable than plutonium in the marine waters. The fraction americium and californium assimilated into tissue from food was very low and did not exceed 5%. Unassimilated labelled food was often retained in the gut for more than 2 mo and released only infrequently in a loosely bound condition. In the event of contamination, this particular feeding-digestion strategy in highly mobile, scavenging isopods could act as a potential biological mechanism for the widespread dispersion of radioactive wastes.     

Dioxins and furans in the atmosphere of São Paulo City, Brazil

Air samples were collected simultaneously at three urban sites in São Paulo City, Brazil, in winter, spring, summer and fall (in 2000 and 2001). Andersen PUF samplers were used for gas and particles sequential sampling. Samples were analyzed using HRGC/HRMS according to US EPA Method 8290. The greater metropolitan area of São Paulo is the largest industrialized region of Latin America and has a highly polluted atmosphere. Concentrations of dioxins and furans, which are well-known toxic chemicals, ranged from 1.14 pg m⁻³ to 13.8 pg m⁻³ (0.047 pg I-TEQ m⁻³ to 0.751 pg I-TEQ m⁻³). Principal component analysis showed that all the variables are highly correlated with one another except the 2,3,7,8-TCDD one. This is consistent with the similar concentration profiles observed for the tetra, penta, hexa, hepta and octa-homologous groups of the three sampling sites studied. At all sites, the most abundant compounds were the hepta and octa congeners. The 2,3,4,7,8-PeCDF accounted for 37–46% of the total toxicity and the 2,3,7,8-TCDD accounted for 7–16%. Highest mass concentrations of PCDD/Fs were found in the site where there is influence of industrial activities and heavy vehicular traffic fueled by gasohol, diesel, and ethanol.     

Temporal variability of airborne bacterial community structure in an urban area

Temporal airborne bacterial genetic community structure and meteorological factors were analysed above an urban area in the northwest of France from December 2003 to April 2004 with a sampling strategy considering different time intervals (from an hour to a month). Principal component analysis (PCA) of B-ARISA (Bacterial-Automated Ribosomal Intergenic Spacer Analysis) profiles revealed a hierarchy in the temporal variability of bacterial community: daily<weekly<seasonal. Co-inertia analysis between B-ARISA data and meteorological factors demonstrated the correlation between the seasonal variability in the bacterial community and climatic conditions such as temperature and relative humidity, whereas daily and weekly variability seemed likely to be managed by other factors such as anthropogenic activities.