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601.
Modelling the Ecological Vulnerability to Forest Fires in Mediterranean Ecosystems Using Geographic Information Technologies 总被引:1,自引:0,他引:1
Beatriz Duguy José Antonio Alloza M. Jaime Baeza Juan De la Riva Maite Echeverría Paloma Ibarra Juan Llovet Fernando Pérez Cabello Pere Rovira Ramon V. Vallejo 《Environmental management》2012,50(6):1012-1026
Forest fires represent a major driver of change at the ecosystem and landscape levels in the Mediterranean region. Environmental features and vegetation are key factors to estimate the ecological vulnerability to fire; defined as the degree to which an ecosystem is susceptible to, and unable to cope with, adverse effects of fire (provided a fire occurs). Given the predicted climatic changes for the region, it is urgent to validate spatially explicit tools for assessing this vulnerability in order to support the design of new fire prevention and restoration strategies. This work presents an innovative GIS-based modelling approach to evaluate the ecological vulnerability to fire of an ecosystem, considering its main components (soil and vegetation) and different time scales. The evaluation was structured in three stages: short-term (focussed on soil degradation risk), medium-term (focussed on changes in vegetation), and coupling of the short- and medium-term vulnerabilities. The model was implemented in two regions: Aragón (inland North-eastern Spain) and Valencia (eastern Spain). Maps of the ecological vulnerability to fire were produced at a regional scale. We partially validated the model in a study site combining two complementary approaches that focused on testing the adequacy of model’s predictions in three ecosystems, all very common in fire-prone landscapes of eastern Spain: two shrublands and a pine forest. Both approaches were based on the comparison of model’s predictions with values of NDVI (Normalized Difference Vegetation Index), which is considered a good proxy for green biomass. Both methods showed that the model’s performance is satisfactory when applied to the three selected vegetation types. 相似文献
602.
Sergio Machado Corrêa Graciela Arbilla Eduardo Monteiro Martins Simone Lorena Quitério Claudinei de Souza Guimarães Luciana Vanni Gatti 《Atmospheric environment (Oxford, England : 1994)》2010,44(19):2302-2308
The fuel matrix used in Brazil is unique around the world. The intensive use of hydrated ethanol, gasohol (gasoline with 25% v/v of ethanol), compressed natural gas (CNG), and biodiesel leads to a peculiar composition of the urban atmosphere. From 1998 to 2002 an increase in formaldehyde levels was observed and since then, a reduction. This work presents a monitoring campaign that was executed from March 2004 to February 2009 by sampling at early morning on every sunny Wednesday for a total of 183 samples. The results indicate a strong reduction in formaldehyde levels from 2004 (average of 135.8 μg m?3 with SD 28.4 μg m?3) to 2009 (average of 49.3 μg m?3 with SD 27.4 μg m?3). The levels of acetaldehyde showed a slight reduction from 2004 (average of 34.9 μg m?3 with SD 8.0 μg m?3) to 2009 (average of 26.8 μg m?3 with SD 11.5 μg m?3). Comparing the results with the concurrent evolution of the fleet and of fuel composition indicates that the observed formaldehyde levels could be associated with the increase in ethanol use and in CNG use by engines with improved technology over the first converted CNG engines. Modelling studies using the OZIPR trajectory model and the SAPRC chemical mechanism indicate that formaldehyde is the main ozone precursor in Rio de Janeiro and acetaldehyde is the forth one. 相似文献
603.
Esther Coz Begoña Artíñano Lisa M. Clark Mark Hernandez Allen L. Robinson Gary S. Casuccio Traci L. Lersch Spyros N. Pandis 《Atmospheric environment (Oxford, England : 1994)》2010,44(32):3952-3962
Scanning electron microscopy coupled to energy-dispersive x-ray spectroscopy (SEM/EDX) was used to quantify individual bioparticles in PM2.5 samples collected during the Pittsburgh Air Quality Study. Microscopy-based estimates of primary biogenic organic aerosol (PBOA) mass were compared to carbohydrate mass associated with PM2.5. Carbohydrates show substantial seasonal variations, with higher concentrations in the spring and the fall. During the summer, carbohydrates were about 30% of the estimated PBOA concentrations, but in the winter carbohydrate concentrations often greatly exceeded the PBOA mass estimate. Spores and insect detritus were the most abundant PBOA types in the summer samples, while winter samples were comprised predominantly of a mixture of microorganisms, insect and vegetative detritus. During the summer PBOA contributed on average 6.9 ± 5.4% by mass of the PM2.5 versus 3.3 ± 1.4% of the PM2.5 mass during the winter. 相似文献
604.
Biljana Škrbić Katarzyna Szyrwińska Nataša Đurišić-Mladenović Piotr Nowicki Janina Lulek 《Environment international》2010,36(8):862-872
Principal component analysis (PCA) was applied to a data set containing the levels of indicator polychlorinated biphenyls (PCBs) in human milk of mothers living in the Wielkopolska region, Poland, in order to investigate the information captured in the PCB patterns and to elucidate the relationship between PCB concentrations in milk and donor characteristics. According to the obtained PCA results milk fat content was the most influential factor affecting the PCB levels in milk of the Wielkopolska cohort. The lifestyle data collected from the questionnaire completed by the donors appeared to have no influence on PCB concentrations in breast milk. The score plots revealed the PCB contents of milk were quite low and uniform with a few outliers, without discrimination observed either between the primipareous and secundipareous females or between donors from the urban and rural areas. Comparison of the PCB levels and profiles of human milk from the Wielkopolska region and from various European and Asian locations made by PCA reflected a generally low background exposure and indicated the possible reasons for the outlying of some samples. In order to enhance the chances of observing the relationship between donor habits and PCB levels in breast milk it was suggested that the questionnaire be redesigned to gather information about vegetable product consumption and indoor air exposure. 相似文献
605.
Using Leventhal's rules as well as the group‐value model of procedural justice, we first examined how the negative effects of perceived racial discrimination on procedural justice judgments can be attenuated by perceived organizational efforts to support diversity. Secondly, we examine how these effects ultimately impact affective commitment and organizational citizenship behavior. We found that employees who believe some individuals in the workplace are discriminating against them on the basis of race tend to report lower levels of procedural justice from the organization. However, this negative relationship was attenuated when employees perceived that their organization was making efforts to support diversity. Results suggest that individuals' perceptions of organizational efforts to support diversity can help restore perceptions of procedural justice for employees who experience racial discrimination at work. Improving procedural justice also positively impacts affective commitment and organizational citizenship behavior directed at the organization. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
606.
Maria Teresa García Gema Duque Ignacio Gracia Antonio de Lucas Juan F. Rodríguez 《Journal of Material Cycles and Waste Management》2009,11(1):2-5
The amount of extruded polystyrene (XPS) waste has increased in recent years due to the increase of its use in the thermal
insulation of buildings, transport vehicles, and refrigerators, among others. Dissolution with suitable solvents to achieve
a volume reduction of more than 100 times without degradation of polymer chains is one of the cheapest and most efficient
methods of recycling XPS. Several environmentally friendly solvents have been tested as dissolution agents for XPS volume
reduction; the action of these solvents does not produce any degradation of polymer chains. The solubility of the polymer
in such solvents at different temperatures was investigated. The solvent can be easily recycled by distillation, obtaining
a high-quality recycled polymer.
Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6 相似文献
607.
C. Domínguez C. Flores J. Caixach L. Mita B. Piña J. Comas J. M. Bayona 《Environmental science and pollution research international》2014,21(21):12336-12344
Interest in identifying pools of antibacterial-resistance genes has grown over the last decade, with veterinary antibiotics (VAs) receiving particular attention. In this paper, a mesoscale study aimed at evaluating the vertical transport of common VAs—namely, fluoroquinolones, tetracyclines, sulfonamides, and lincosamides in agricultural soil subjected to drip irrigation—was performed under greenhouse conditions. Accordingly, leachates of cropped and uncropped soil, amended with swine-slurry leading to 19–38 μg kg?1 (dry mass) antibiotics in the soil, were analyzed over the course of the productive cycle of a lettuce (42 days) with three sampling campaigns (N?=?24). High lincomycin (LCM) concentrations (30–39 μg L?1) were detected in the leachates collected from the swine-slurry-amended soil. The highest LCM mass recovered in the leachates (30.1?±?1.63 %) was obtained from cropped experimental units. In addition, the LCM leaching constant and its leaching potential as obtained from the first-order model were higher in the leachates from the cropped experimental units. Lower concentrations of sulfadimethoxine were also detected in leachates and in soil. Enrofloxacin and oxytetracycline occurred only in soil, which is consistent with high soil interaction. 相似文献
608.
G. Pliego J. A. Zazo M. I. Pariente I. Rodríguez A. L. Petre P. Leton J. García 《Environmental science and pollution research international》2014,21(21):12129-12134
The treatment of a non-biodegradable agrochemical wastewater has been studied by coupling of preliminary coagulation—flocculation step and further Fenton oxidation. High percentages of chemical oxygen demand (COD) removal (up to 58 %) were achieved in a first step using polyferric chloride as coagulant. This reduced significantly the amount of H2O2 required in the further Fenton oxidation. Using the stoichiometric amount relative to COD around 80 % of the remaining organic load was mineralized. The combined treatment allowed achieving the regional discharge limits of ecotoxicity at a cost substantially lower than the solution used so far where these wastewaters are managed as hazardous wastes. 相似文献
609.
Brenda Vila Nova Santana Talita Oliveira de Araújo Guilherme Carvalho Andrade Larisse de Freitas-Silva Kacilda Naomi Kuki Eduardo Gusmão Pereira Aristéa Alves Azevedo Luzimar Campos da Silva 《Environmental science and pollution research international》2014,21(4):2550-2562
Setaria parviflora (Poir.) Kerguélen and Paspalum urvillei Steudel are grasses that grow naturally in a soil with high iron contents. This study aimed to characterize morphoanatomically and histochemically the iron phytotoxicity on leaves and evaluate the phytoextraction potential of these grasses. Saplings were cultivated in hydroponic solution with and without excess Fe-EDTA. Regarding measurements taken on leaves, reduction was observed among treatments of Fe-EDTA on height values of abaxial epidermis and bundle sheath in both species. As for iron histolocalization, stronger reaction was observed in leaves of S. parviflora, in comparison with P. urvillei. Anatomical damage, such as protoplast retraction, irregular xylem, changes in cell volume, and cell collapse, and visual symptoms, like leaf bronzing, chlorosis, and necrosis, were similar in both species when exposed to excess iron; however, P. urvillei showed more severe damage. This species accumulated more iron in shoots than S. parviflora and therefore is more favorable for use in phytoextraction. The root system of both species accumulated higher iron concentrations in relation to shoots. 相似文献
610.
Juan José Cabello Eras Dayli Covas Varela Gilberto D. Hernández Pérez Alexis Sagastume Gutiérrez Dunia García Lorenzo Carlo Vandecasteele Luc Hens 《Environment, Development and Sustainability》2014,16(1):195-215
The urban quality of life (UQoL) from objective dimension was analyzed in the main Cuban cities. An Urban Quality of Life Index (UQoLI) was developed in collaboration with 60 experts (five in each city). These experts belong to one of two categories: in charge of the planning of the city and members of the Municipal Council of Administration. One hundred and forty-two directors of the Local District Administration also participated in the analysis. The UQoLI includes three dimensions: social services, economic performance, and urban services, the importance of which is weighed according to expert criteria. A Ranking of the studied cities, sorted by the UQoLI, shows a tendency of increase it UQoL in the west even and central regions. This tendency contradicts one of the foundations of the Cuban sustainable development framework, i.e., equity. 相似文献