Concentrations and distribution of 210Pb in bird feathers and its potential for tracing age and flight times

Bird feathers have been widely used as environmental indicators, providing key information on environmental pollution. However, there is little available information on the adsorption of natural radioactivity in bird feathers and consequently, its impact on the field of movement ecology is not yet known. This study investigates the concentration and distribution of 210Pb in wing- and tail-feathers of different bird species with contrasting migratory strategies, and discusses its potential use as a tracer of age and flight times. Adsorption of 210Pb in bird feathers is directly related to the interaction of feathers with air, therefore it is hypothesised that the presence of this radionuclide is proportional to the length of flight times, and is asymmetrically distributed in flight feathers. Consequently, a significant difference is expected between 210Pb concentrations in feathers of long-distance migrants when compared to sedentary species. For this purpose, a total of 45 samples from eight individuals of three bird species with distinct migratory strategies were analysed: a highly aerial and long-distance migratory species (Common swift Apus apus), and two largely sedentary species widely distributed across Europe (Great tit Parus major and Tawny owl Strix aluco). Novel findings show that the content of 210Pb in bird feathers of adult migratory birds is much higher than in sedentary birds or juvenile individuals, demonstrating this naturally occurring radionuclide can provide information about the contact time between feathers and air. Additionally, 210Pb adsorption was not evenly distributed in bird feathers. The findings provide a new method to trace age and flight time of birds using 210Pb in feathers, complementing conventional techniques in bird migration studies.

Evaluation of synergy during co-pyrolysis of torrefied sawdust, coal and paraffin. A kinetic and thermodynamic dataset

This article aims to clarify and expand the information published in the article Evaluation of synergy during co-pyrolysis of torrefied sawdust, coal and paraffin. A kinetic and thermodynamic study, which evaluate kinetically and thermodynamically the existence of synergies during the co-pyrolysis of binary and ternary blends of coal, torrefied pine sawdust and paraffin. These materials were selected because they have been used before in the preparation of briquettes for the steel industry with good results. In order to facilitate the understanding and reproducibility of the main article, the following descriptions, dataset and figures have been provided: description and formulation of iso-conversional methods, some TGA curves and the standard deviation of the TG analysis, the activation energy of all the raw materials and their blends at different level of conversion using Friedman, Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods, as well as, the linear plots for their calculations for the KAS and FWO models; also the thermodynamic parameters for pyrolysis of all the samples studied and the theoretical and experimental plots for prediction of solid state reaction mechanism using Criado method of several weights of paraffin are include.

Soil organic carbon accumulation rates on Mediterranean abandoned agricultural lands

Secondary succession on abandoned agricultural lands can produce climate change mitigation co-benefits, such as soil carbon sequestration. However, the accumulation of soil organic carbon (SOC) in Mediterranean regions has been difficult to predict and is subject to multiple environmental and land management factors. Gains, losses, and no significant changes have all been reported. Here we compile chronosequence data (n = 113) from published studies and new field sites to assess the response of SOC to agricultural land abandonment in peninsular Spain. We found an overall SOC accumulation rate of +2.3% yr^-1 post-abandonment. SOC dynamics are highly variable and context-dependent. Minimal change occurs on abandoned cereal croplands compared to abandoned woody croplands (+4% yr^-1). Accumulation is most prevalent within a Goldilocks climatic window of ~13-17 °C and ~450-900 mm precipitation, promoting >100% gains after three decades. Our secondary forest field sites accrued 40.8 Mg C ha^-1 (+172%) following abandonment and displayed greater SOC and N depth heterogeneity than natural forests demonstrating the long-lasting impact of agriculture. Although changes in regional climate and crop types abandoned will impact future carbon sequestration, abandonment remains a low-cost, long-term natural climate solution best incorporated in tandem with other multipurpose sustainable land management strategies.

The Influence of Markets on the Nutrition Transition of Hunter-Gatherers: Lessons from the Western Amazon

For many centuries, hunter-gatherer societies relied on subsistence practices and traditional diets. However, forces of globalization have increased market involvement, thereby fueling the nutrition transition of hunter-gatherer societies. We review the academic literature on market involvement of hunter-gatherer societies in the Western Amazon and its consequences on diet, health and well-being. First, we elaborate on four main determinants of market involvement (accessibility, monetary income, wild meat trade and social capital), showing how each determinant draws individuals toward or away from markets. Thereafter, we discuss how these determinants alter diet, health and well-being. Our results add to the understanding of the complex relations between market involvement, dietary change, health and well-being of indigenous societies. Furthermore, they bring to light that additional research is needed on the topic to support decision-makers and help preserve indigenous values.

Kinetics of co-pyrolysis of sawdust, coal and tar

Two coals, sawdust and coal tar were selected to prepare briquettes. Thermogravimetric analyses at three heating rates (i.e. 10, 20 and 30°C/min) and up to 1000°C were carried out with the briquette components. Four blends were prepared and the experimental decomposition profiles were compared with the calculated data taking into account the amount of each component in the blend. No interaction was found when comparing the experimental and calculated decomposition profiles of the blends. Isoconversional models OFW (Ozawa-Flynn-Wall) and KAS (Kissinger-Akahira-Sunose) were used to obtain the activation energies of the blend components. The activation energies obtained were introduced in the Coats-Redfern (CR) model to derive the pre-exponential factors. The thermal decomposition profiles calculated using the kinetic parameters were in good agreement with the experimental results in the case of the briquette components, but worse results were obtained in the case of the blends due to their greater complexity.

Pyrolysis of a waste from the grinding of scrap tyres

The fibres that are used to reinforce tyres can be recovered as a waste in the process of grinding of scrap tyres. In this paper beneficiation through pyrolysis is studied since the fibres are made up of polymers with a small amount of rubber because the latter is difficult to separate. The experiments were performed at three temperatures (400, 550 and 900°C) in a horizontal oven. The three products - gas, oil and char - obtained from the pyrolysis were investigated. The composition of the gas was analyzed by means of gas chromatography. The oil was studied by gas chromatography and infrared spectroscopy. The char porous structure was determined by N(2) adsorption. In addition, the topography of the chars was studied by means of scanning electron microscopy (SEM). The products resulting from the pyrolysis of the fibres were compared with those obtained from scrap rubber.

The influence of wind direction on the capture of the wood warbler (Phylloscopus sibilatrix), an uncommon migratory species in the western Mediterranean

The wood warbler (Phylloscopus sibilatrix) is a migratory species in the western Mediterranean wintering in the Gulf of Guinea region, West Africa. In autumn and spring, this species, along with the populations breeding in Ireland and Britain, uses the Italian peninsula as its main axis of migration. From the data of captured birds at several ringing stations in the western Mediterranean (Balearic Islands and coastal Iberian Peninsula), we analyzed capture rates of the species during spring migration from 1993 to 2007. Based on the selection of days with a significant number of captures and those without captures, we analyzed the effect of wind direction over the western Mediterranean to determine a relationship between winds and the number of captures. From a total of 663 wood warblers captured between 1993 and 2007, a total of 31 days have been selected as significant days with a high number of captures, and 31 days have been selected as no-capture days. On days of maximum captures, winds coming from an easterly direction, i.e. Algeria and Tunisia, were dominant, indicating days with a clear eastern component. Contrary to expected results, captures were also made on days when the wind direction was predominantly from a northerly direction. Analysis of the origin of the winds in north eastern Spain (western Mediterranean) revealed that the majority of northerly winds originated from Africa and not from Europe as is usual for this region. Days or periods selected as no-capture days were characterized by winds coming from a northerly (European origin) or westerly direction.

Recycling of hazardous waste materials in the coking process

Every year the coking industry produces a significant amount of tarry and other wastes in byproducts plants. For the most part these wastes have not been put to any practical use. In addition, an integrated factory produces several waste oils which differ in composition and quantity, e.g., wastes from the steel rolling-mill process. In this work, the possibility of using such waste materials as binders in a partial briquetting process for metallurgical coke production is explored. By means of this coking procedure, a strong metallurgical coke not inferior in quality to coke from conventional coal blends is produced at pilot and semi-industrial scales. The use of such wastes, some of which are classified as hazardous materials, will avoid the need for dumping, thereby contributing to the protection of the environment as well as reducing the costs related to waste disposal.

Influences of wind flow on stopover decisions: the case of the reed warbler Acrocephalus scirpaceus in the Western Mediterranean

Wind directions measured at two different heights (850 hPa and 700 hPa) and at different hours of the night were analysed during the spring migration passage at a bird stopover site located in the western Mediterranean, in order to evaluate the importance of wind components for a stopover decision. From a huge ringing campaign of bird migration in north-east Spain, data from the reed warbler Acrocephalus scirpaceus have been used for the analysis. From a total of 2,478 reed warblers captured between 1993 and 1997 data recording significant days, with a high number of captures, and decrease days, with few captures, have been selected to develop an analysis of wind direction in relation to stopover and flight resumption. On days with a high capture the winds had mainly a fourth-quadrant flow (from the north, north-west and west), these being mainly head winds. Winds with westerly component (from the north-west, west and south-west), which enhance the flight, account for the majority of the days when there was a low capture of reed warblers. Wind direction therefore appears to be a determining factor for stopover decisions and resumption of flight for the reed warblers at an intermediate stage of their spring migration where topographical characteristics govern the winds.

Study of the composition of tars produced from blends of coal and polyethylene wastes using high-performance liquid chromatography

Tars produced at semi-industrial scale in a coke oven of 6 x 10(3) kg capacity were used to investigate the effect of using polyethylene waste as an additive in the carbonization process with coal. The polyethylene wastes used were low-density polyethylene from the agriculture greenhouses and high-density polyethylene from domestic sources. The high-performance liquid chromatography analysis of the soluble fractions in toluene and carbon disulfide, using two polystyrene-divinylbenzene columns and a mixture of dichloromethane-methanol as a mobile phase, provides useful information on the composition of tars and their derived pitches in terms of the substitution and molecular topology of polynuclear aromatic compounds (PACs). Differences in composition of tars produced with polyethylene waste at 1% (w/w) have been found to be negligible, while a higher amount of the waste (3%, w/w) promoted the formation of peri-condensed PACs at the expense of the substituted cata-condensed PACs. This behaviour is due to more extensive secondary reactions of tar precursors via dealkylation and aromatic condensation taking place during the carbonization process as a consequence of a more viscous co-carbonizing system. Changes in tar composition caused by this amount of polyethylene waste addition were comparable to those promoted by an increase in the carbonization temperature at semi-industrial and industrial ovens and by the coal preheating before the carbonization process. The characteristic features in tar composition were also found for the derived pitches from tars obtained with the polyethylene waste addition.

Gas chromatographic study of the volatile products from co-pyrolysis of coal and polyethylene wastes

The aim of this study was to determine the volatile products distribution of co-processing of coal with two plastic wastes, low-density polyethylene from agriculture greenhouses and high-density polyethylene from domestic uses, in order to explain the observed decrease in coal fluidity caused by polyethylene waste addition. Polymeric materials, although they are not volatile themselves, may be analysed by gas chromatography through the use of pyrolysis experiments. In this way, a series of pyrolysis tests were performed at 400 and 500 degrees C in a Gray-King oven with each of the two plastic wastes, one high-volatile bituminous coal and blends made up of coal and plastic waste (9:1, w/w, ratio). The pyrolysis temperatures, 400 and 500 degrees C, were selected on the basis of the beginning and the end of the coal plastic stage. The organic products evolved from the oven were collected, dissolved in pyridine and analysed by capillary gas chromatography using a flame ionization detector. The analysis of the primary tars indicated that the amount of n-alkanes is always higher than that of n-alkenes and the formation of the alkenes is favoured by increasing the pyrolysis temperature. However, this effect may be influenced by the size of the hydrocarbon. Thus, the fraction C17-C31 showed a higher increase of n-alkenes/n-alkanes ratio than other fractions. On the other hand, the difference between the experimental and estimated values from tars produced from single components was positive for n-alkanes and n-alkenes, indicating that co-pyrolysis of the two materials enhanced the chemical reactivity during pyrolysis and produced a higher conversion than that from individual components.