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81.
Urban sprawl and its evolution over relatively short periods of time demands that we develop statistical tools to make best use of the routinely produced land use data from satellites. An efficient smoothing framework to estimate spatial patterns in binary raster maps derived from land use datasets is developed and presented in this paper. The framework is motivated by the need to model urbanization, specifically urban sprawl, and also its temporal evolution. We frame the problem as estimation of a probability of urbanization surface and use Bayesian P-splines as the tool of choice. Once such a probability map is produced, with associated uncertainty, we develop exploratory tools to identify regions of significant change across space and time. The proposal is used to study urbanisation and its development around the city of Bologna, Emilia Romagna, Italy, using land use data from the Cartography Archive of Emilia Romagna Region for the period 1976–2008.  相似文献   
82.
ABSTRACT

The aim of this study is to investigate of how the concept of ‘integrated food and energy systems’ or IFES production networks could be applied – within the specific context of Eastern Cuba’s agricultural and agro-industrial sectors – as an innovative approach to improve food and energy security. The Province of Santiago de Cuba in southeast Cuba was the focus of this study; its existing operations, infrastructure, resource flows and scarcities, and actor relationships provide the basis of the data used for the evaluation.

The authors investigated the regional context, identify potential members of an agricultural and agro-industrial network in three municipalities of the province, and identify the main residuals and by-products of key facilities. Potential avenues for by-product valorization are investigated along with the possible influence/impacts on the sustainability of the surrounding systems and actors. A conceptual model for a regional network for integrated food and energy production is then provided based upon the development of three agricultural/agro-industrial scenarios: influence at the farm level, regional agro-industrial networks, and ‘anchor tenant’ eco-industrial systems. The main challenges and opportunities for the development of the networks are described with recommendations for addressing such where possible.  相似文献   
83.
Zooplankton encounter rates are dependent not only on both sensory and swimming performances of the organisms, but also on the distribution pattern of food particles. Increasing evidences indicate that, in natural conditions, phytoplankton is often aggregated in thin layers. In the present contribution we investigate the concomitant effects of motion complexity and habitat fragmentation on the number of encounters realised by virtual continuously moving copepods adopting different motion strategies. Our simulated organisms move in an environment characterised by the presence of thin patches of phytoplankton, and their swim follows five motion rules (pure random walk, correlated random walk with three different time scales, self-avoiding random walk), each characterised by a typical value of the three-dimensional fractal dimension D3D. Compared to a uniform distribution, for a given motion rule the clustering of prey particles increases the variance of encounters, while no remarkable effect is reported in the average number of particles intercepted. These results broaden our understanding of the behavioural efficiency in freely swimming zooplankters and improve our knowledge of the functioning of aquatic systems.  相似文献   
84.
Al2O3, MgO, SiO2 and ZnO-supported nickel catalysts were prepared and evaluated in the ethanol steam reforming for hydrogen production. It is shown that the catalytic behavior can be influenced depending on the experimental conditions employed and chemical composition of the catalyst.  相似文献   
85.
Chlorpyrifos is an anticholinesterase organophosphate insecticide widely used in Argentina in the production of food derived from animal, fruit and horticultural origin and is reported as a residue within these products. Local reference values for acetyl and butyrylcholinesterase were determined in Aberdeen Angus bovine and cross bred cattle (n = 25), a requirement to be able to evaluate toxicity of commercial organophosphate and carbamate formulations. The activity of cholinesterase enzymes presented an overall mean of 2,183.00 ± 485.6 IU L?1 for erythrocyte acetylcholinesterase and 203.1 ± 42.06 IU L?1 for plasma butyrylcholinesterase, which are used as reference values for meat steers within a system of intensive production in a semi-arid region. The toxic potential of chlorpyrifos in steers of the same breeds (n = 12) was assessed applying chlorpyrifos 15.00% Tipertox® in a single therapeutic dose of 7.50 mg kg?1 by topical route. Prior to application and then on day 1 and day 21 post-application, both blood cholinesterases, serum chlorpyrifos concentration by ultra-high resolution liquid chromatography with mass detector, analysis of blood counts, total proteins, liver enzymes, urea and creatinine were evaluated. The mean plasma concentration of chlorpyrifos was 27.90 ug L?1 at 24 h. The findings indicate that the therapeutic treatment of castrated male bovines treated with chlorpyrifos, applied by pour-on according to the manufacturer's instructions, does not cause changes in the variables evaluated.  相似文献   
86.
The present article analyses a unique database of 220 dam-related environmental conflicts, retrieved from the Global Atlas on Environmental Justice (EJAtlas), and based on knowledge co-production between academics and activists. Despite well-known controversial, social, and environmental impacts of dams, efforts to increase renewable energy generation have reinstated the interest into hydropower development globally. People affected by dams have largely denounced such ‘unsustainabilities’ through collective non-violent actions. Nevertheless, we found that repression, criminalization, violent targeting of activists and assassinations are recurrent features of conflictive dams. Violent repression is particularly high when indigenous people are involved. Indirect forms of violence are also analysed through socio-economic, environmental, and health impacts. We argue that increasing repression of the opposition against unwanted energy infrastructures does not only serve to curb specific protest actions, but also aims to delegitimize and undermine differing understanding of sustainability, epistemologies, and world views. This analysis cautions that allegedly sustainable renewables such as hydropower often replicates patterns of violence within a frame of an ‘extractivism of renewables’. We finally suggest that co-production of knowledge between scientists, activists, and communities should be largely encouraged to investigate sensitive and contentious topics in sustainability studies.  相似文献   
87.
Environmental Science and Pollution Research - The presence of Brazilian native bees can improve tomato production by increasing pollination effectiveness. However, the extensive use of pesticides...  相似文献   
88.

In order to study the bioaccumulation of Pb, Cr, Ni, and Zn and the stress response, the floating aquatic plant Limnobium laevigatum was exposed to increasing concentrations of a mixture of these metals for 28 days, and its potential use in the treatment of wastewater was evaluated. The metal concentrations of the treatment 1 (T1) were Pb 1 μg L−1, Cr 4 μg L−1, Ni 25 μg L−1, and Zn 30 μg L−1; of treatment 2 (T2) were Pb 70 μg L−1, Cr 70 μg L−1, Ni 70 μg L−1, and Zn 70 μg L−1; and of treatment 3 (T3) were Pb 1000 μg L−1, Cr 1000 μg L−1, Ni 500 μg L−1, and Zn 100 μg L−1, and there was also a control group (without added metal). The accumulation of Pb, Cr, Ni, and Zn in roots was higher than in leaves of L. laevigatum, and the bioconcentration factor revealed that the concentrations of Ni and Zn in the leaf and root exceeded by over a thousand times the concentrations of those in the culture medium (2000 in leaf and 6800 in root for Ni; 3300 in leaf and 11,500 in root for Zn). Thus, this species can be considered as a hyperaccumulator of these metals. In general, the changes observed in the morphological and physiological parameters and the formation of products of lipid peroxidation of membranes during the exposure to moderate concentrations (T2) of the mixture of metals did not cause harmful effects to the survival of the species within the first 14 days of exposure. Taking into account the accumulation capacity and tolerance to heavy metals, L. laevigatum is suitable for phytoremediation in aquatic environments contaminated with moderated concentrations of Cr, Ni, Pb, and Zn in the early stages of exposure.

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89.
Data from ten years of integrated monitoring were used here to evaluate whether pine needles are a feasible tool for an assessment of long-term trends of the atmospheric contamination. Pine needles collected once a year were compared to high volume air samples collected for 24 h, every 7 days, and passive air samples integrated over 28-day periods. Results showed the same concentration patterns of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) captured in needles and high volume samples. Passive air samplers were less efficient in sampling the particle-bound compounds. Theoretical air volume equivalent to each needle sample (VEQ) was calculated as a ratio of the needle concentration over the mean air concentration. Results indicated different equivalent volumes for PAHs and organochlorines, possibly due to the faster degradation rates of PAHs in needles. The most important finding is that in the long term a needle monitoring gives very similar information on temporal trends of the atmospheric pollution as does a high volume air monitoring.  相似文献   
90.
The objective of this work was to study the technological feasibility of treating wastewater from a personal care industry (PCI-WW) in a mechanically stirred anaerobic sequencing batch biofilm reactor (AnSBBR) containing immobilized biomass on polyurethane foam. An assessment was made on how system efficiency and stability would be affected by: increasing organic load; supplementation of nutrients and alkalinity; and different feed strategies. The AnSBBR operated with 8-h cycles, stirring speed of 400 rpm, temperature of 30 °C, and treated with 2.0 L wastewater per cycle. First the efficiency and stability of the AnSBBR were studied when submitted to an organic loading rate (OLR) of 3.1–9.4 gCOD/(L d), and when the PCI-WW was supplemented with nutrients (sucrose, urea, trace metals) and alkalinity. The AnSBBR was shown to be robust and presented stability and removal efficiency exceeding 90%. At an OLR of 12.0 gCOD/(L d) efficiency became difficult to maintain due to the presence of commercial cleansers and disinfectants in the wastewater lots. In a subsequent stage the AnSBBR treated the wastewater supplemented with alkalinity, but with no nutrients at varying feed strategies and maintaining an OLR of approximately 9.0 gCOD/(L d). The first strategy consists of feeding 2.0 L of the influent batchwise [OLR of 9.4 gCOD/(L d)]. In the second 1.0 L of influent was fed-batchwise and an additional 1.0 L was fed fed-batchwise [OLR of 9.2 gCOD/(L d)], i.e., in relation to the first strategy the feed volume was maintained but supplied in different periods. In the third strategy 1.0 L of treated effluent was maintained in the reactor and 1.0 L of influent was fed fed-batchwise [OLR of 9.0 gCOD/(L d)], i.e., in relation to the first strategy the feed volume was different but the feed period was the same and the OLR was maintained by increasing the influent concentration. Comparison of the first and second strategies revealed that organic matter removal efficiency was unaffected (exceeding 90%). The third strategy resulted in a reduction in average removal efficiency from 91 to 83% when compared to the first one. A kinetic study resulted in first order kinetic parameters ranges from 0.42 to 1.46 h−1 at OLRs from 3.1 to 12.0 gCOD/(L d), respectively, and the second feed strategy [OLR of 9.2 gCOD/(L d)] was shown to be the most favorable.  相似文献   
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