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41.
This paper describes how energy policy can be evaluated in practice. The goal is to make policy makers aware of how an evaluation can be based on scientific principles and to help economists appreciate how an evaluation can be performed if strong empirical evidence is lacking. We have built a basic evaluation framework and have applied this to a selection of Dutch energy policy instruments, namely production subsidies and their complementary non-financial instrument, DEN-B. Our evaluation criterion was effectiveness, defined as the extent to which policy instruments contribute to achieving policy goals. The evaluation was based on existing ex post evaluations complemented by interviews and other available data. We conclude that production subsidies and DEN-B were (partly) effective. Furthermore, the Dutch government increased effectiveness by reconsidering the design of production subsidies. We also formulate lessons for future policy evaluations and energy markets policies. 相似文献
42.
Zita Sebesvari Fabrice G. Renaud Susanne Haas Zachary Tessler Michael Hagenlocher Julia Kloos Sylvia Szabo Alejandro Tejedor Claudia Kuenzer 《Sustainability Science》2016,11(4):575-590
The sustainability of deltas worldwide is under threat due to the consequences of global environmental change (including climate change) and human interventions in deltaic landscapes. Understanding these systems is becoming increasingly important to assess threats to and opportunities for long-term sustainable development. Here, we propose a simplified, yet inclusive social–ecological system (SES)-centered risk and vulnerability framework and a list of indicators proven to be useful in past delta assessments. In total, 236 indicators were identified through a structured review of peer-reviewed literature performed for three globally relevant deltas—the Mekong, the Ganges–Brahmaputra–Meghna and the Amazon. These are meant to serve as a preliminary “library” of potential indicators to be used for future vulnerability assessments. Based on the reviewed studies, we identified disparities in the availability of indicators to populate some of the vulnerability domains of the proposed framework, as comprehensive social–ecological assessments were seldom implemented in the past. Even in assessments explicitly aiming to capture both the social and the ecological system, there were many more indicators for social susceptibility and coping/adaptive capacities as compared to those relevant for characterizing ecosystem susceptibility or robustness. Moreover, there is a lack of multi-hazard approaches accounting for the specific vulnerability profile of sub-delta areas. We advocate for more comprehensive, truly social–ecological assessments which respond to multi-hazard settings and recognize within-delta differences in vulnerability and risk. Such assessments could make use of the proposed framework and list of indicators as a starting point and amend it with new indicators that would allow capturing the complexity as well as the multi-hazard exposure in a typical delta SES. 相似文献
43.
Gabriel Ibarra-Berastegi Jon Sáenz Agustín Ezcurra Unai Ganzedo Javier Díaz de Argandoña Iñigo Errasti Alejandro Fernandez-Ferrero Josué Polanco-Martínez 《Atmospheric environment (Oxford, England : 1994)》2009,43(25):3829-3836
In Bilbao (Spain), an air quality network measures sulphur dioxide levels at 4 locations. The objective of this paper is to develop a practical methodology to identify redundant sensors and evaluate a network's capability to correctly follow and represent SO2 fields in Bilbao, in the frame of a continuous network optimization process.The methodology is developed and tested at this particular location, but it is general enough to be useable at other places as well, since it is not tied neither to the particular geographical characteristics of the place nor to the phenomenology of the air quality over the area.To assess the spatial variability of SO2 measured at 4 locations in the area, three different techniques have been used: Self-Organizing Maps (SOMs), cluster analysis (CA) and Principal Component Analysis (PCA). The results show that the three techniques yield the same results, but the information obtained via PCA can be helpful not only for that purpose but also to throw light on the major mechanisms involved. This might be used in future network optimization stages. The main advantage of cluster analysis and SOMs is that they provide readily interpretable results. All the calculations have been carried out using the freely available software R. 相似文献
44.
Castello L Viana JP Watkins G Pinedo-Vasquez M Luzadis VA 《Environmental management》2009,43(2):197-209
Fishers and small-scale fisheries worldwide have been marginalized historically. Now it is clear that integrating fishers
in management processes is key to resource conservation, but it is less clear how to do it. Here, based on a literature review and new information, we present and analyze a case in which the participation
of fishers in the management process was crucial in recovering an overexploited small-scale fishery for the pirarucu (Arapaima spp.) in the Amazon Basin, Brazil. In 8 years of experimental management, from 1999 to 2006, the population of pirarucu increased
9-fold (from about 2200 to 20,650 individuals), harvest quotas increased 10-fold (from 120 to 1249 individuals), and fishers’
participation in the management process increased and they benefited from increased monetary returns. Additionally, the number
of communities conducting the management scheme increased from 4 in 1999 to 108 in 2006, following the demands of fishers
and regional government agencies. Based on our analysis, we suggest that the participation of fishers in the management of
other small-scale fisheries in the world can be improved by focusing on (1) applying the knowledge and skills of fishers in
resource monitoring and management, (2) bridging knowledge systems among all involved stakeholders, (3) collaborating with
fishers that are interested in, and capable of conducting, resource conservation schemes, and (4) conducting management under
conditions of uncertainty. 相似文献
45.
Hegetschweiler KT van Loon N Ryser A Rusterholz HP Baur B 《Environmental management》2009,43(2):299-310
Urban forests are popular recreation areas in Europe. Several of these temperate broad-leaved forests also have a high conservation
value due to sustainable management over many centuries. Recreational activities, particularly the use of fireplaces, can
cause extensive damage to soil, ground vegetation, shrubs, and trees. Firewood collection depletes woody debris, leading to
a loss of habitat for specialized organisms. We examined the effects of fireplace use on forest vegetation and the amount
of woody debris by comparing disturbed and control plots in suburban forests in northwestern Switzerland. At frequently used
fireplaces, we found reduced species densities in the ground vegetation and shrub layer and changes in plant species composition
due to human trampling within an area of 150–200 m2. Picnicking and grilling also reduced the height and changed the age structure of shrubs and young trees. The amount of woody
debris was lower in disturbed plots than in control plots. Pieces of wood with a diameter of 0.6–7.6 cm were preferentially
collected by fireplace users. The reduction in woody debris volume extended up to a distance of 16 m from the fire ring, covering
an area of 800 m2 at each picnic site. In order to preserve the ecological integrity of urban forests and to maintain their attractiveness
as important recreation areas, we suggest depositing logging residues to be used as firewood and to restrict visitor movements
near picnic sites. 相似文献
46.
Agri-environment programs aim to secure environmental and social stewardship services through payments to farmers. A critical
component of many agri-environment programs is an agri-environment index (AEI) used to quantify benefits and target investments.
An AEI will typically comprise multiple indicators, which are weighted and combined using a utility function, to measure the
benefit of investment options (e.g., projects, farms, regions). This article presents a review of AEIs with 11 case studies
from agri-environment programs in the United States, Australia, and the United Kingdom. We identify a generic procedure used
to define AEIs and explore the implications of alternative methodological approaches. We conclude that AEIs have become an
extremely important policy instrument and make suggestions for their improvement. 相似文献
47.
On experimental setup in bioelectromagnetics 总被引:1,自引:1,他引:0
Bioeffects created by electromagnetic field (EMF) are the subject of intensive studies. This paper critically considers estimations
of exposure to EMF in bioelectromagnetic experiments. Results of calculations presented herein show the significant role of
the presence of conducting bodies (the exposure system) near an object under test on EMF energy absorption as well as mutual
interactions between simultaneously exposed objects. Our aims herein are twofold: firstly to find a way to refer measurement
results to free-space conditions in order to enable comparison of results obtained in different laboratories, and secondly
to show that EMF energy absorption in any exposed object is different and that this difference is a function of the size of
the exposure system, the number of exposed objects, and the particular properties (i.e., the electromagnetic structure) of
the objects. In the authors’ opinion the existence of interactions caused by the presence of the exposure system and other
exposed objects is a reason why remarkable differences are observed between experiments performed even under supposedly identical
conditions. The presented considerations and conclusion suggest wider participation of physicists and engineers in bioelectromagnetic
experiments in order to ensure the correctness of metrological aspects of these experiments. 相似文献
48.
Urbanization and its impact on groundwater: a remote sensing and GIS-based assessment approach 总被引:1,自引:0,他引:1
The perils of unplanned urbanization and increasing pressure of human activities on hydro-geomorphologic system often result
in modification of the existing recharge mechanism, which leads to many environmental consequences. In the present research,
an attempt has been made to investigate the applicability of remote sensing and geographical information system (GIS) in dealing
with spatial and temporal variability of dynamic phenomena, like urbanization and its impact on groundwater. This paper covers
primarily, quantitative and qualitative impacts of urban growth on the behavior of aquifer in Ajmer city (India). Urban growth
of the Ajmer city in last 17 years has been estimated from the satellite images. Database related to urbanization and groundwater
has been created in GIS. Groundwater recharge has been computed using a water balance approach known as Water Level Fluctuation
Methodology. Recharge estimation methodology has been implemented in GIS to introduce the spatial variability of hydro-geological
characteristics. Further, temporal and spatial variations in groundwater quality and quantity have been correlated with urban
growth using overlay analysis in GIS. The study reveals a general decline in water table and quality with urbanization. Further,
remote sensing and GIS technologies have been found useful in assessment of spatial and temporal phenomena of urbanization
and its impact on groundwater system. 相似文献
49.
Natalia Moreno Mar Viana Marco Pandolfi Andrs Alastuey Xavier Querol Servando Chinchn Juan Francisco Pinto Federico Torres Juan Manuel Díez Jos Saz 《Journal of environmental management》2009,91(1):133-141
Remodelling works are frequent in harbour areas, given that they must adapt to rapidly changing market requirements. Depending on their nature (construction, demolition, etc.), these works may be carried out during long periods of time and thus exert a significant impact on the air quality at the harbours and their surroundings. The air quality at the Valencia harbour was studied during an enlargement project. Four sampling stations aimed to cover the major dust-emitting activities in the harbour. In addition, a sampling campaign was carried out to collect dust materials at their emission sources (e.g., loading and unloading of clinker and petroleum coke, as well as the enlargement works). Differences obtained between PM levels at the monitoring sites were correlated with the distance between sampling stations and enlargement works and/or harbour operations, as well as with the preferential wind direction. In all cases, the days with the highest PM_10 levels were linked to wind directions coinciding with the location of the enlargement works or the clinker and petroleum coke stocks. Classic source apportionment methodologies (PCA and CMB) were applied to the data, but their interpretation was complex due to the similar chemical signatures of PM originating from direct and fugitive emissions from stocked materials (e.g., clinker), and the enlargement works. To overcome this difficulty, a novel non-statistical approach was used to obtain quantitative estimations of the contributions from sources (petroleum coke and clinker), based on the correlation between specific PM components (e.g., carbonaceous species) and source tracers (e.g., V). Finally, a qualitative test using phenolphthalein was devised to identify the presence of clinker on the filters, which provided positive results. This novel tracer approach is thus recommended for harbour authorities. 相似文献
50.
The whole relationship between environmental variables and firm performance: Competitive advantage and firm resources as mediator variables 总被引:1,自引:0,他引:1
María D. Lpez-Gamero Jos F. Molina-Azorín Enrique Claver-Corts 《Journal of environmental management》2009,90(10):3110-3121
The examination of the possible direct link between environmental protection and firm performance in the literature has generally produced mixed results. The present paper contributes to the literature by using the resource-based view as a mediating process in this relationship. The study specifically tests whether or not the resource-based view of the firm mediates the positive relationships of proactive environmental management and improved environmental performance with competitive advantage, which also has consequences for financial performance. We also check the possible link between the adoption of a pioneering approach and good environmental management practices. Our findings support that early investment timing and intensity in environmental issues impact on the adoption of a proactive environmental management, which in turn helps to improve environmental performance. The findings also show that a firm's resources and competitive advantage act as mediator variables for a positive relationship between environmental protection and financial performance. This contribution is original because the present paper develops a comprehensive whole picture of this path process, which has previously only been partially discussed in the literature. In addition, this study clarifies a relevant point in the literature, namely that the effect of environmental protection on firm performance is not direct and can vary depending on the sector considered. Whereas competitive advantage in relation to costs influences financial performance in the IPPC law sector, the relevant influence in the hotel sector comes from competitive advantage through differentiation. 相似文献