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31.
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
32.
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
33.
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
34.
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
35.
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
36.
脉冲电晕反应器结构对乙硫醇消除效果的影响 总被引:2,自引:1,他引:1
研究了脉冲电晕等离子体反应器结构的变化对乙硫醇消除效果的影响规律。结果表明,在反应器内设置折流板,可以增加气流的湍动程度,有利于活性粒子与污染物的充分接触,从而提高消除率。高压电极间距对电晕区范围及消毒效果有较大影响,间距较小将导致各电极产生的电场相互干扰明显,消除率减小;而电极间距过大,虽然电极间电场分布相互干扰小,但是反应器内可排布的电极数减少,总电晕区减少,消除率也减小。根据实验结果,电极间距设置为50 mm比较合理。另外,在相同的电场强度和脉冲频率下,毛刺形高压电极比线电极结构能耗低,能量利用率高。 相似文献
37.
含中间层的DSA电极电催化氧化硝基苯废水的研究 总被引:1,自引:0,他引:1
为了提高难降解有机废水的可生化性,以及更高效地去除废水中的特征污染物,同时避免二次污染,利用自制的含锡锑中间层的钌钯氧化物涂层电极对有机废水中的硝基苯进行处理,并利用SEM、XRD等方法对电极中间层、表层进行微观表征。微观测试表明,基体、中间层、表层之间结合力较强,有利于增强电极寿命;水处理实验表明,电催化氧化反应体系适合高浓度有机废水的处理,由于该反应体系需要外加电解质加强传质,这在实际运用中为废水中盐度的处理提供了一种新的途径,当电流密度为20 mA/cm2、电解质浓度为10 g/L、pH=5、极板间距=2 cm时,电催化氧化体系对硝基苯具有较高的去除效率。 相似文献
38.
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
39.
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
40.
This research is a combination of gender studies, which highlights differences between men and women, and workplace research, which focuses on the performances that are assumed to affect employee satisfaction. The study proposes a multi-dimensional assessment model that enables consideration of several workplace issues in tandem. Focusing on user satisfaction, the first part of the study is a holistic approach concerned with technical, functional and behavioral variables that provides a broad understanding about gender (in)differences. Personalization, the core issue of the second part of the study, is measured through personal display items, autonomous behavior and office layout preferences of men and women employees. The findings indicate the presence of significant gender differences in terms of satisfaction felt with regard to the behavioral variables. The results also support previous findings indicating that men and women use different personal display items in order to personalize their offices. More women were diagnosed to be changing their room layout on a temporary basis whereas men and women were evidenced for having similar attitudes in making permanent changes and in preferring an office layout for themselves. The findings suggest that gender difference is still a valid subject in workplace research although the differences may not be as sharp as the conventional gender difference myth claims, implying a better understanding of the issues that differently satisfy men and women. 相似文献