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351.
João L. Guilherme Victoria R. Jones Inês Catry Martin Beal Maria P. Dias Steffen Oppel Juliet A. Vickery Chris M. Hewson Stuart H. M. Butchart Ana S. L. Rodrigues 《Conservation biology》2023,37(1):e14002
The conservation of long-distance migratory birds requires coordination between the multiple countries connected by the movements of these species. The recent expansion of tracking studies is shedding new light on these movements, but much of this information is fragmented and inaccessible to conservation practitioners and policy makers. We synthesized current knowledge on the connectivity established between countries by landbirds and raptors migrating along the African–Eurasian flyway. We reviewed tracking studies to compile migration records for 1229 individual birds, from which we derived 544 migratory links, each link corresponding to a species’ connection between a breeding country in Europe and a nonbreeding country in sub-Saharan Africa. We used these migratory links to analyze trends in knowledge over time and spatial patterns of connectivity per country (across species), per species (across countries), and at the flyway scale (across all countries and all species). The number of tracking studies available increased steadily since 2010 (particularly for landbirds), but the coverage of existing tracking data was highly incomplete. An average of 7.5% of migratory landbird species and 14.6% of raptor species were tracked per country. More data existed from central and western European countries, and it was biased toward larger bodied species. We provide species- and country-level syntheses of the migratory links we identified from the reviewed studies, involving 123 populations of 43 species, migrating between 28 European and 43 African countries. Several countries (e.g., Spain, Poland, Ethiopia, Democratic Republic of Congo) are strategic priorities for future tracking studies to complement existing data, particularly on landbirds. Despite the limitations in existing tracking data, our data and results can inform discussions under 2 key policy instruments at the flyway scale: the African–Eurasian Migratory Landbirds Action Plan and the Memorandum of Understanding on the Conservation of Migratory Birds of Prey in Africa and Eurasia. 相似文献
352.
Mockaitis G Ratusznei SM Rodrigues JA Zaiat M Foresti E 《Journal of environmental management》2006,79(2):198-206
An assessment was made of cheese whey treatment in a mechanically stirred anaerobic sequencing batch reactor (ASBR) containing granular biomass. The effect of increasing organic load and decreasing influent alkalinity supplementation (as sodium bicarbonate) was analyzed. The reactor operated on 8-h cycles with influent COD concentrations of 500, 1000, 2000 and 4000 mg/L, corresponding to volumetric organic loads of 0.6 to 4.8 mgCOD/L.d. Organic COD removal efficiencies were always above 90% for filtered samples. These results were obtained with an optimized alkalinity supplementation of 50% (ratio between mass of NaHCO3 added and mass of influent mgNaHCO3/mgCOD) in the assays with 500 and 1000 mgCOD/L and of 25% in the assays with 2000 and 4000 mgCOD/L. Initial alkalinity supplementation was equal to the mass of influent COD (100%). The system showed formation of viscous polymer-like substances. These were probably of microbiological origin occurring mainly at influent CODs of 2000 and 4000 mg/L and caused some biomass flotation. This could, however be controlled to enable efficient and stable reactor operation. 相似文献
353.
Climate change is one of the major worldwide environmental concerns. It is especially the case in many developed countries, where the greenhouse gas emissions responsible for this change are mainly concentrated. For the first time, the Kyoto Protocol includes an international agreement for the reduction of the net emissions of these gases. To fulfil this agreement measures designed to reduce or limit current emissions have to be brought into force. Consequently, fears have arisen about possible consequences on competitiveness and future development of manufacturing activities and the need for support mechanisms for the affected sectors is obvious. In this paper, we carry out a study of the emissions of gases responsible for climate change in Asturias (Spain), a region with an important economic presence of sectors with intensive emissions of CO(2), the chief greenhouse gas. To be precise, in the first place, the volumes of direct emissions of the said gases in 1995 were calculated, showing that the sectors most affected by the Kyoto Protocol in Asturias are iron and steel and electricity production. Secondly, input-output analysis was applied to determine the direct and indirect emissions and the direct, indirect and induced emissions of the different production sectors, respectively. The results derived from the direct and indirect emissions analysis and their comparison with the results of the former allow us to reach some conclusions and environmental policy implications. 相似文献
354.
Gomes Fernanda Bento Rosa Cândido Vinícius Bignoto da Rocha Vargas Isabela Salgado de Paiva Luiz Evaristo Dias Silva Jonathas Batista Gonçalves Branco Otavio Eurico de Aquino Castro Samuel Rodrigues 《Journal of Material Cycles and Waste Management》2023,25(1):144-156
Journal of Material Cycles and Waste Management - Leakage modeling can be crucial for environmental management and control of waste landfills. However, defining boundary conditions for these models... 相似文献
355.
356.
Extractability and mobility of mercury from agricultural soils surrounding industrial and mining contaminated areas 总被引:1,自引:0,他引:1
This study focussed on a comparison of the extractability of mercury in soils with two different contamination sources (a chlor-alkali plant and mining activities) and on the evaluation of the influence of specific soil properties on the behaviour of the contaminant. The method applied here did not target the identification of individual species, but instead provided information concerning the mobility of mercury species in soil. Mercury fractions were classified as mobile, semi-mobile and non-mobile. The fractionation study revealed that in all samples mercury was mainly present in the semi-mobile phase (between 63% and 97%). The highest mercury mobility (2.7 mg kg(-1)) was found in soils from the industrial area. Mining soils exhibited higher percentage of non-mobile mercury, up to 35%, due to their elevated sulfur content. Results of factor analysis indicate that the presence of mercury in the mobile phase could be related to manganese and aluminium soil contents. A positive relation between mercury in the semi-mobile fraction and the aluminium content was also observed. By contrary, organic matter and sulfur contents contributed to mercury retention in the soil matrix reducing the mobility of the metal. Despite known limitations of sequential extraction procedures, the methodology applied in this study for the fractionation of mercury in contaminated soil samples provided relevant information on mercury's relative mobility. 相似文献
357.
Adsorption of Remazol Red 198 onto magnetic N-lauryl chitosan particles: equilibrium, kinetics, reuse and factorial design 总被引:1,自引:0,他引:1
Debrassi A Baccarin T Demarchi CA Nedelko N Ślawska-Waniewska A Dłużewski P Bilska M Rodrigues CA 《Environmental science and pollution research international》2012,19(5):1594-1604
Purpose
The discharge of colored effluents from industries is an important environmental issue and it is indispensable to remove the dyes before the water gets back to the rivers. The magnetic adsorbents present the advantage of being easily separated from the aqueous system after adsorption by positioning an external magnetic field.Methods
Magnetic N-lauryl chitosan (L-Cht/??-Fe2O3) particles were prepared and characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy, and vibrating sample magnetometry. Remazol Red 198 (RR198) was used as a reactive dye model for adsorption on L-Cht/??-Fe2O3. The adsorption isotherms were performed at 25°C, 35°C, 45°C, and 55°C and the process was optimized using a 23 factorial design (analyzed factors: pH, ionic strength, and temperature). The desorption and regeneration studies were performed in a three times cycle.Results
The characterization of the material indicated that the magnetic particles were introduced into the polymeric matrix. The pseudo-second order was the best model for explaining the kinetics and the Langmuir?CFreundlich was the best-fitted isotherm model. At room temperature, the maximum adsorption capacity was 267?mg?g?1. The material can be reused, but with a decrease in the amount of adsorbed dye.Conclusions
L-Cht/??-Fe2O3 is a promising material to remove RR198 and probably other similar reactive dyes from aqueous effluents. 相似文献358.
Zaharia C 《Environmental science and pollution research international》2012,19(6):2448-2455
Introduction
The paper analyses the environment pollution state in different case studies of economic activities (i.e. co-generation electric and thermal power production, iron profile manufacturing, cement processing, waste landfilling, and wood furniture manufacturing), evaluating mainly the environmental cumulative impacts (e.g. cumulative impact against the health of the environment and different life forms).Materials and methods
The status of the environment (air, water resources, soil, and noise) is analysed with respect to discharges such as gaseous discharges in the air, final effluents discharged in natural receiving basins or sewerage system, and discharges onto the soil together with the principal pollutants expressed by different environmental indicators corresponding to each specific productive activity. The alternative methodology of global pollution index (I GP * ) for quantification of environmental impacts is applied.Results and discussion
Environmental data analysis permits the identification of potential impact, prediction of significant impact, and evaluation of cumulative impact on a commensurate scale by evaluation scores (ESi) for discharge quality, and global effect to the environment pollution state by calculation of the global pollution index (I GP * ).Conclusions
The I GP * values for each productive unit (i.e. 1.664?C2.414) correspond to an ??environment modified by industrial/economic activity within admissible limits, having potential of generating discomfort effects??. The evaluation results are significant in view of future development of each productive unit and sustain the economic production in terms of environment protection with respect to a preventive environment protection scheme and continuous measures of pollution control. 相似文献359.
Diversity of shrub tree layer, leaf litter decomposition and N release in a Brazilian Cerrado under N, P and N plus P additions 总被引:1,自引:0,他引:1
Jacobson TK Bustamante MM Kozovits AR 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2236-2242
This study investigated changes in diversity of shrub-tree layer, leaf decomposition rates, nutrient release and soil NO fluxes of a Brazilian savanna (cerrado sensu stricto) under N, P and N plus P additions. Simultaneous addition of N and P affected density, dominance, richness and diversity patterns more significantly than addition of N or P separately. Leaf litter decomposition rates increased in P and NP plots but did not differ in N plots in comparison to control plots. N addition increased N mass loss, while the combined addition of N and P resulted in an immobilization of N in leaf litter. Soil NO emissions were also higher when N was applied without P. The results indicate that if the availability of P is not increased proportionally to the availability of N, the losses of N are intensified. 相似文献
360.
Chemical recycling of poly(ethylene terephthalate) PET waste in the melt state through alcoholysis with multifunctional alcohol—pentaerythrytol
(PENTE)—was performed in a internal mixer Haake Rheomix 600, at 250 °C, 60 rpm, for 10 min, in presence of zinc acetate. The
following PET:PENTE molar ratios 1:0; 1:0.16; 1:0.48 and 1:3.4 were studied. The chemical structure of the end-products was
characterized by FT-IR. Thermal properties and X-ray diffractograms were also assessed. The esterification and alcoholysis
reactions took place and were dependent on the molar ratio. The first one is dominant in compositions rich in PET leading
to the formation of star-branching copolymer. The second one brings about the PET oligomerization and an oligoester named
herein bis(tri-hydroxylneopentyl) terephthalate (BTHNPT) was obtained. The end-products have potential application as asphalt
additive or adhesive. 相似文献