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81.
Annette Piorr Fabrizio Ungaro Arianna Ciancaglini Kathrin Happe Amanda Sahrbacher Claudia Sattler Sandra Uthes Peter Zander 《Environmental Science & Policy》2009,12(8):1122-1136
The recent and upcoming reforms of the Common Agricultural Policies (CAPs) aim at strengthening the multifunctional role of agriculture, acknowledging the differences in economic, environmental and social potentials within European regions. This paper presents results from an integrated assessment of existing and future policies within the framework set up in the FP6 EU project MEA-Scope. Spatial explicit procedures allow for the MEA-Scope modelling tools to provide information related to regional, environmental and socio-economics settings. The impact of different policy scenarios on structural change, land abandonment and cropping pattern of typical farms has been assessed based on linked agent-based (ABM) and Linear Programming (LP) models at regional and farm scale for two study areas. For the German case study area Ostprignitz-Ruppin (OPR), the issue of policy targeting has been addressed by relating non-commodity outputs (NCOs) to soil quality and protection status. For the Italian case study area (Mugello), changes in landscape patterns in terms of increased fragmentation or homogeneity as affected by changes in agricultural intensity have been analysed using semivariance analysis. The spatial explicit approach highlighted the relevance of case study research in order to identifying response structures and explaining policy implementation patterns. 相似文献
82.
83.
Teresa Pamatz-Bolaños Denis A. Cabrera-Munguia Horacio González Rosa E. Del Río José L. Rico Gabriela Rodríguez-García 《International Journal of Green Energy》2018,15(8):465-472
Caesalpinea eriostachys seed oil, as a source of triglycerides with potential application for biodiesel production in Mexico is introduced. Its lipid profile obtained by Gas Chromatography-Mass Spectrometry (GC-MS) revealed saturated and unsaturated glycerol esters as the constituents. Therefore, heterogeneous and homogeneous catalyzed transesterification reactions were assayed employing ZnAl hydrotalcites and KOH, as the catalysts, respectively. The transesterification reactions yielded 59% for Zn/Al(2), 79% for Zn/Al(4), and 90% for KOH, depicting typical behavior, as in biodiesel production data from literature, where Zn-Al hydrotalcites or KOH were assayed. The caloric, density, viscosity values, and fatty acid methyl esters profile from reaction products were concordant to EN 14214, suggesting C. eriostachys as a promising feedstock for biodiesel production. 相似文献
84.
Monika Suškevičs Thomas Hahn Romina Rodela Biljana Macura Claudia Pahl-Wostl 《Journal of Environmental Planning and Management》2018,61(7):1085-1112
Learning is considered as a promising mechanism to cope with rapid environmental change. The implications of learning for natural resource management (NRM) have not been explored in-depth and the evidence on the topic is scattered across multiple sources. We provide a qualitative review of types of learning outcomes and consider their manifestations in NRM across selected empirical literature. We conducted a systematic search of the peer-reviewed literature (N = 1,223) and a qualitative meta-synthesis of included articles, with an explicit focus on learning outcomes and NRM changes (N = 53). Besides social learning, we found several learning concepts used, including policy and transformative learning, and multiple links between learning and NRM reported. We observe that the development of skills, together with a system approach involving multi-level capacities, is decisive for implications of learning for NRM. Future reviews could systematically compare how primary research applies different learning concepts and discusses links between learning and NRM changes. 相似文献
85.
Biodegradation kinetics of surfactants in seawater. 总被引:4,自引:0,他引:4
In this paper, a general kinetic model for degradation processes of surfactants is proposed. The model equation is v = K2S2 + K1S + K0, where v is the substrate consumption rate in the biodegradation process, S is the surfactant concentration in the medium and K2, K1, and K0 are kinetic constants. From this general expression, different simplified equations can be obtained (where K0 = 0; K2 and K0 = 0; K2 = 0; K2 and K1 = 0), which are representative of the process for different operating conditions. This model was tested by measuring the degradation of two different surfactants (Sodium dodecyl benzene sulfonate, LAS; and Sodium dodecyl sulfate, DSNa) under two different temperatures (5 and 20 degrees C). Values predicted by the model are close to experimental data obtained. 相似文献
86.
Susana García-Alonso Rosa María Pérez-Pastor María Luisa Sevillano-Castaño 《Environmental science and pollution research international》1999,6(3):147-150
The focus of this study was to characterize the concentration levels of selected PCBs and compare them to compiled data in
order to contribute to the international database. The sampling site is located in the outskirts of Madrid and can be considered
an open urban area. 32 samples of air were taken from February 1998 to June 1998 by using a high volume air sampler. Glass
fiber filters and polyurethane foam (PUF) were used to collect the paniculate and gas phase material, respectively.
PUF plugs were Soxhlet extracted and filters were ultrasonically extracted by using pesticide-grade hexane and dichloromethane,
respectively. The cleanup procedure was carried out on a florisil column with hexane and hexane/dichloromethane as elution
solvents.
GC/MS in a selected ion monitoring mode was used for quantification and 29 selected PCBs congeners were analyzed. 相似文献
87.
88.
Miguel Costa Leal Patricia N. Pochelon Teresa Lopes da Silva Alberto Reis Rui Rosa Ricardo Calado 《Marine Biology》2013,160(4):763-772
Offspring quality of decapod crustaceans has been widely studied, with special emphasis on the sources of variability determining embryonic and larval quality. Nevertheless, maternal provisioning has commonly been overlooked as a potential source of offspring within-brood variability. In the present study, the existence of variable maternal provisioning was assessed through the analysis of the fatty acid (FA) profile of newly extruded embryos from different regions of the brooding chamber of Homarus gammarus. Significant differences in the FA profile of embryos sampled from different pleopods and sides of the brooding chamber were recorded. Significant deviations of the overall mean of each surveyed female were also observed for essential FA, particularly 20:4n-6, 20:5n-3 and 22:6n-3. Lipid energy available to fuel embryogenesis also varied among embryos sampled from different regions of the brooding chamber. Results suggest variable female investment at oocyte production, which may be amplified during the incubation period of developing embryos by differential lipid catabolism. For the first time, maternal provisioning is evidenced as an additional source for within-brood variability in the FA profile of embryos. 相似文献
89.
To examine the suitability of benthic foraminifera and their test deformations as bioindicators of pollution in coastal marine environments, we studied foraminifera and metal concentrations in 72 marine sediment samples, collected from the inner shelf along the Sicilian coast (Gulfs of Palermo and Termini) and on the south-eastern coast of Lampedusa Island. These areas are characterised by different environmental conditions. On the basis of pollution sources and foraminiferal assemblages, we recognised different zones in the Gulf of Palermo. The most polluted zones showed high metal concentrations, and low diversity of benthic foraminifera with species typical of stressed environments. By contrast, the lowest polluted zones showed a high population density and the highest percentages of epiphytes. Epiphytes were abundant where a Posidonia oceanica meadow was present and decreased in the most polluted zones. Sediments of the Gulf of Termini and Lampedusa exhibited high percentages of benthic foraminifera typical of well-oxygenated waters and low concentrations of metals, with the exception of sites located near sewage outfalls and harbour areas. Furthermore, even though deformed tests are commonly known in natural stressed environmental conditions, this study shows that in the most polluted zones, benthic foraminifera were characterised by the highest percentages of deformed individuals. 相似文献
90.
María Oliveira Rosa M. Crujeiras Alberto Rodríguez-Casal 《Environmental and Ecological Statistics》2013,20(1):1-17
The goal of this work is to introduce nonparametric kernel methods for density and regression estimation for circular data, and illustrate their use by a brief simulation study and real data application. Apart from supplying practitioners with a license free and easy to run code for the use of these methods, our aim is also to provide solutions to practical problems that may be encountered in their application. The real data examples belong to the International Polar Year project, concerned with the environmental change in the polar regions. 相似文献