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One of the main objectives of landscape ecology is to orient land-use planning by providing indications of optimal ecosystem patterning to support nature conservation. A frequent limitation to the practical use of the findings of landscape ecological studies is that they tend to focus on the identification and computation of indicators rather than on their interpretation and assessment. This paper presents and discusses the use of a methodology to formalise expert opinion through the elicitation of multi-attribute value functions. In particular, the value functions aim at assessing spatial indicators so as to provide an overall judgment of the viability of different ecosystem patches. The result consisted of the ranking of the ecosystems according to their degree of viability and therefore their suitability for nature conservation. The method of formalising expert opinion and knowledge complements traditional analyses based on the measurement of spatial ecological indicators.  相似文献   
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Total reflection x-ray fluorescence spectroscopy (TXRF) is proposed for the elemental chemical analysis of crustal environmental samples, such as sediments and soils. A comparative study of TXRF with respect to flame atomic absorption spectroscopy and inductively coupled plasma optical emission spectroscopy was performed. Microwave acid digestion and suspension preparation methods are evaluated. A good agreement was found among the results obtained with different spectroscopic techniques and sample preparation methods for Cr, Mn, Fe, Ni, Cu, and Zn. We demonstrated that TXRF is suitable for the assessment of environmental contamination phenomena, even if the errors for Pb, As, V, and Ba are ingent.  相似文献   
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This article investigates the impact that the electricity tariff reform is likely to have on investments in renewable energies (i.e., photovoltaics) and the adoption of energy efficiency measures (i.e., installation of heat pumps and efficient home appliances) in the residential market in Italy. The study develops detailed cost comparisons and simulations considering two different investment scenarios (before and after the reform) to conclude that the reform will: (i) have a negative impact on investments in photovoltaic systems; (ii) favor the adoption of energy efficiency measures, such as efficient home appliances.  相似文献   
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Vietnam, in the ongoing transition to market economies, has to cope with high rural poverty and a dramatic process of forest loss and environment degradation, particularly in the mountainous regions. The government considers rural poverty as the main cause of environment degradation, associated with slash-and-burn cultivation and to an unclear definition of property rights on forest land. In 1993, the government launched a Forest Land Allocation programme aiming to lease forest lands to individual households and, on this basis, to solve food security problems, halt the increasing environment degradation and preserve the remaining forests.To evaluate the results of this land reform policy, two upland pilot communes have been intensively monitored. The environmental and economic impacts of the forest land reform allocation in the two study areas are presented, after providing a background on the Vietnamese situation of mountain zones. On the basis of these findings, it is discussed as to whether the current forest land allocation process may actually promote local development and natural resources conservation, and under what conditions. Deforestation problems must be tackled also with new macroeconomic policies (e.g. credit programmes to support sustainable agriculture practices) and social policy (e.g. reduction of demographic pressure), together with the reform of the State institutions (e.g. State Forest Enterprises) involved in management of the forest areas.  相似文献   
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Vione D  Minero C  Housari F  Chiron S 《Chemosphere》2007,69(10):1548-1554
2,4-Dichlorophenol (2,4-DCP) and 2,6-dichlorophenol (2,6-DCP) undergo oxidation, nitrosation and nitration in the presence of nitrate under UV irradiation. Nitration is favoured under acidic conditions, most likely because HNO(2) is formed on nitrate photolysis. The most likely photonitration pathway is the reaction between radiation-excited dichlorophenols (DCP*) and HNO(2). HNO(2) is also able to nitrate DCP in the dark with elevated yields. Irradiation also causes DCP direct photolysis, which is more efficient for the dichlorophenolate anions. The photolysis of the dichlorophenols and that of the dichlorophenolates also produce different intermediates, by dechlorination in the former and ring contraction in the latter case.  相似文献   
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This paper presents three spatial decision-support models (Boolean logic, binary evidence and overlapping index of multiple class maps) to perform a land suitability analysis for sanitary landfill siting. The study was carried out in the basin of Lake Cuitzeo, Mexico, with the objective of locating areas that comply with environmental regulations and with the inter-municipality criterion, i.e., that are accessible by at least two municipalities. Biophysical and socio-economic data were processed in a Geographic Information System (GIS). The three models differ in their complexity and restrictiveness. The Boolean logic model is easier to apply and more restrictive than the other two, because it is based on the assessment of single attributes. On the other hand, the binary data and overlapping index methods are relatively more complex because they require attribute weighting. The results showed that 23 of the 28 municipalities included in the basin have at least one area that was classified as highly suitable. The most suitable areas covered from 63.8 to 204.5 km(2) (from 1.5% to 5%), and they are not distributed homogeneously, but clustered around four main sites. The larger and most suitable of these sites is located in the central part of the basin, and it can be accessed by five of the most densely populated municipalities. The proposed approach represents a low-cost alternative to support a common spatial decision-making process in developing countries.  相似文献   
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