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941.
The aim of the present work is to design a model for evaluating the impact of planned infrastructures on species survival at the territorial scale by calculating a connectivity index. The method developed involves determining the effective distance of displacement between patches of the same habitat, simplifying earlier models so that there is no dependence on specific variables for each species. A case study is presented in which the model was used to assess the impact of the forthcoming roads and railways included in the Spanish Strategic Infrastructure and Transport Plan (PEIT, in its Spanish initials).This study took into account the habitats of peninsular Spain, which occupies an area of some 500,000 km2. In this territory, the areas deemed to provide natural habitats are defined by Directive 92/43/EEC. The impact of new infrastructures on connectivity was assessed by comparing two scenarios, with and without the plan, for the major new road and railway networks. The calculation of the connectivity index (CI) requires the use of a raster methodology based on the Arc/Info geographical information system (GIS). The actual calculation was performed using a program written in Arc/Info Macro Language (AML); this program is available in FragtULs (Mancebo Quintana, 2007), a set of tools for calculating indicators of fragmentation caused by transport infrastructure (http://topografia.montes.upm.es/fragtuls.html).The indicator of connectivity proposed allows the estimation of the connectivity between all the patches of a territory, with no artificial (non-ecologically based) boundaries imposed. The model proposed appears to be a useful tool for the analysis of fragmentation caused by plans for large territories.  相似文献   
942.
Using information on a basic or “lifeline” level of domestic water use obtained from a water demand function based on a Stone–Geary utility function, a minimum water threshold of 128 m3 per household per year was estimated in a sample of municipalities in Southern Spain. As a second objective, water affordability indexes were then calculated that relate the cost of such lifeline to average municipal income levels. The analysis of the factors behind the differences in that ratio across Andalusian municipalities shows that the relative cost of purchasing the lifeline appears inversely related to average income levels, revealing an element of regressivity in the component of water tariffs affecting the least superfluous part of the household’s consumption. The main policy recommendation would involve redesigning water tariffs in order to improve access for lower income households to an amount of water sufficient to cover their basic needs. The proposed methodology could be applied to other geographical areas, both from developed and from developing countries, in order to analyze the degree of progressivity of the water tariffs currently in effect and in order to guide the design of more equitable regulatory policies.  相似文献   
943.
Fecal contamination of water bodies causes a public health problem and economic loss. To control such contamination management actions need to be guided by sound science. From 2007–2009 a study was undertaken to determine the sources of fecal bacteria contamination to the marine waters adjoining the Town of Wrightsville Beach, North Carolina, USA. The research effort included sampling for fecal coliform and Enterococcus bacteria, sampling for optical brighteners, dye studies, and use of molecular bacterial source tracking techniques including polymerase chain reaction (PCR) and terminal restriction fragment polymorphism (T-RFLP) fingerprinting of the Bacteroides–Prevotella group. Of the 96 samples collected from nine locations during the study, the water contact standard for Enterococcus was exceeded on 13 occasions. The T-RFLP fingerprint analyses demonstrated that the most widespread source of fecal contamination was human, occurring in 38% of the samples, with secondary ruminant and avian sources also detected. Optical brightener concentrations were low, reflecting a lack of sewage line leakage or spills. A lack of sewer leaks and lack of septic systems in the town pointed toward discharge from boat heads into the marine waters as the major cause of fecal contamination; this was supported by dye studies. Based on these data, the Town initiated action to have the U.S. Environmental Protection Agency declare the coastal waters (out to 3 nautical miles), the nearby Atlantic Intracoastal Waterway and its tributaries a no-discharge zone (NDZ) to alleviate the human fecal pollution. The Town garnered supporting resolutions from other local communities who jointly petitioned the North Carolina Department of Environmental and Natural Resources. This State regulatory agency supported the local government resolutions and sent an application for an NDZ to the EPA in April 2009. The EPA concurred, and in February 2010 the coastal waters of New Hanover County, NC, became the first marine area on the U.S. eastern seaboard between Delaware and the Florida Keys to be declared a no-discharge zone.  相似文献   
944.
This article examines the use of forests in a protected area by nearby agriculturalists in central Vietnam. Research indicates that the majority of rural farmers interviewed who lived near a state designated protected area were receiving both subsistence and cash incomes from forest-based activities, primarily from the collection of forest products. However, much of the collection of forest produce was officially illegal, as it occurred in state protected forests, and interdiction efforts were on the increase. Yet, little attention has been paid in Vietnam to the need for income substitution for households who lose access to forest produce as a result of conservation enforcement, particularly in the case of farmers who live near, but not in, protected areas; their resources use has been ‘invisible’ due to a lack of attention and research on the topic. This misunderstanding of the importance of forests to rural farmers has the potential to result in households facing adverse welfare and livelihood outcomes as protected areas boundaries are tightened, and local communities face increased opportunity costs due to stricter conservation enforcement. The article concludes that substitution for loss of income due to conservation activities would best be achieved through carefully targeted interventions to specific high-impact and high-dependency households. Additionally, investments in new sources of wage labor and other low capital-input activities, rather than in agriculture, would likely be of most benefit.  相似文献   
945.
In Salah Gas Project in Algeria has been injecting 0.5–1 million tonnes CO2 per year over the past 5 years into a water-filled strata at a depth of about 1800–1900 m. Unlike most CO2 storage sites, the permeability of the storage formation is relatively low and comparatively thin with a thickness of about 20 m. To ensure adequate CO2 flow-rates across the low-permeability sand-face, the In Salah Gas Project decided to use long-reach (about 1–1.5 km) horizontal injection wells. In an ongoing research project we use field data and coupled reservoir-geomechanical numerical modeling to assess the effectiveness of this approach and to investigate monitoring techniques to evaluate the performance of a CO2 injection operation in relatively low-permeability formations. Among the field data used are ground surface deformations evaluated from recently acquired satellite-based inferrometry (InSAR). The InSAR data shows a surface uplift on the order of 5 mm per year above active CO2 injection wells and the uplift pattern extends several km from the injection wells. In this paper we use the observed surface uplift to constrain our coupled reservoir-geomechanical model and conduct sensitivity studies to investigate potential causes and mechanisms of the observed uplift. The results of our analysis indicate that most of the observed uplift magnitude can be explained by pressure-induced, poro-elastic expansion of the 20-m-thick injection zone, but there could also be a significant contribution from pressure-induced deformations within a 100-m-thick zone of shaly sands immediately above the injection zone.  相似文献   
946.
The benefits of using organic waste as fertilizer and soil amendment should be assessed together with the environmental impacts due to the possible presence of heavy metals (HMs). This study involved analysing major element and HM contents in raw and size-fractionated organic wastes (17 sewage sludges and composts) from developed and developing countries. The overall HM concentration pattern showed an asymmetric distribution due to the presence of some wastes with extremely high concentrations. HM concentrations were correlated with the size of cities or farms where the wastes had been produced, and HM were differentiated with respect to their origins (geogenic: Cr–Ni; anthropogenic agricultural and urban: Cu–Zn; anthropogenic urban: Cd–Pb). Size fractionation highlighted Cd, Cu, Zn and Pb accumulation in fine size fractions, while Cr and Ni were accumulated in the coarsest. HM associations with major elements revealed inorganic (Al, Fe, etc.) bearing phases for Cr and Ni, and sulfur or phosphorus species for Cd, Cu Pb and Zn.  相似文献   
947.
A landfill reclamation project was considered to recover landfill airspace and soil, reduce future groundwater impacts by removing the waste buried in the unlined area, and optimize airspace use at the site. A phased approach was utilized to evaluate the technical and economic feasibility of the reclamation project; based on the results of these evaluations, approximately 6.8 ha of the unlined cells were reclaimed. Approximately 371,000 in-place cubic meters of waste was mined from 6.8 ha in this project. Approximately 230,600 cubic meters of net airspace was recovered due to beneficial use of the recovered final cover soil and reclaimed soil as intermediate and daily cover soil, respectively, for the current landfill operations. This paper presents the researchers’ landfill reclamation project experience, including a summary of activities pertaining to reclamation operations, an estimation of reclamation rates achieved during the project, project costs and benefits, and estimated composition of the reclaimed materials.  相似文献   
948.
Using solid state 13C NMR data and elemental composition in a molecular mixing model, we estimated the molecular components of the organic matter in 16 recycled organic (RO) wastes representative of the major materials generated in the Sydney basin area. Close correspondence was found between the measured NMR signal intensities and those predicted by the model for all RO wastes except for poultry manure char. Molecular nature of the organic matter differed widely between the RO wastes. As a proportion of organic C, carbohydrate C ranged from 0.07 to 0.63, protein C from <0.01 to 0.66, lignin C from <0.01 to 0.31, aliphatic C from 0.09 to 0.73, carbonyl C from 0.02 to 0.23, and char C from 0 to 0.45. This method is considered preferable to techniques involving imprecise extraction methods for RO wastes. Molecular composition data has great potential as a predictor of RO waste soil carbon and nutrient outcomes.  相似文献   
949.
The production of hydrogen through Anaerobic Digestion (AD) has been investigated to verify the efficacy of several pretreatment processes. Three types of waste with different carbon structures have been tested to obtain an extensive representation of the behavior of the materials present in Organic Waste (OW). The following types of waste were selected: Sweet Product Residue (SPR), i.e., confectionary residue removed from the market after the expiration date, Organic Waste Market (OWM) refuse from a local fruit and vegetable market, and Coffee Seed Skin (CSS) waste from a coffee production plant. Several pretreatment processes have been applied, including physical, chemical, thermal, and ultrasonic processes and a combination of these processes. Two methods have been used for the SPR to remove the packaging, manual (SPR) and mechanical (SPRex). A pilot plant that is able to extrude the refuse to 200 atm was utilized. Two parameters have been used to score the different pretreatment processes: efficiency (ξ), which takes into account the amount of energy produced in the form of hydrogen compared with the available energy embedded in the refuse, and efficacy (η), which compares the efficiency obtained using the pretreated refuse with that obtained using the untreated refuse. The best result obtained for the SPR was the basic pretreatment, with η = 6.4, whereas the thermal basic pretreatment gave the highest value, η = 17.0 for SPRex. The best result for the OWM was obtained through a combination of basic/thermal pretreatments with η = 9.9; lastly, the CSS residue with ultrasonic pretreatment produced the highest quantity of hydrogen, η = 5.2.  相似文献   
950.
Factors affecting occupational hygiene were measured at the solid waste transferring plant at Hyvinkää and at the optic separation plant in Hämeenlinna. Measurements consisted of volatile organic compounds (VOCs) and bioaerosols including microbes, dust and endotoxins.The most abundant compounds in both of the plants were aliphatic and aromatic hydrocarbons, esters of carboxylic acids, ketones and terpenes. In terms of odour generation, the most important emissions were acetic acid, 2,3-butanedione, ethyl acetate, alpha-pinene and limonene due to their low threshold odour concentrations. At the optic waste separation plant, limonene occurred at the highest concentration of all single compounds of identified VOCs. The concentration of any single volatile organic compound did not exceed the occupational exposure limit (OEL) concentration. However, 2,3-butanedione as a health risk compound is discussed based on recent scientific findings linking it to lung disease.Microbe and dust concentrations were low at the waste transferring plant. Only endotoxin concentrations may cause health problems; the average concentration inside the plant was 425 EU/m3 which clearly exceeded the threshold value of 90 EU/m3. In the wheel loader cabin the endotoxin concentrations were below 1 EU/m3. High microbial and endotoxin concentrations were measured in the processing hall at the optic waste separation plant. The average concentration of endotoxins was found to be 10,980 EU/m3, a concentration which may cause health risks. Concentrations of viable fungi were quite high in few measurements in the control room. The most problematic factor was endotoxins whose average measured concentrations was 4853 EU/m3.  相似文献   
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