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501.
Illegal fishing poses a major threat to conservation of marine resources worldwide. However, there is still limited empirical research that quantifies illegal catch levels. We used the randomized response technique to estimate the proportion of divers and the quantities of loco (Concholepas concholepas) they extracted illegally. Loco have been managed for the past 17 years through a territorial user rights for fisheries system (TURFs) in Chile. Illegal fishing of loco was widespread within the TURFs system. Official reported landings (i.e., legal landings) accounted for 14–30% of the total loco extraction. Our estimates suggest that ignoring the magnitude of illegal fishing and considering only official landing statistics may lead to false conclusions about the status and trends of a TURFs managed fishery. We found evidence of fisher associations authorizing their members to poach inside TURFs, highlighting the need to design TURFs systems so that government agencies and fishers’ incentives and objectives align through continuous adaptation. Government support for enforcement is a key element for the TURFs system to secure the rights that are in place.  相似文献   
502.
Environmental Science and Pollution Research - Anthropogenic land use change (ALUC) satisfies human needs but also impacts aquatic ecosystems. Aquatic ecosystems are intrinsically linked with...  相似文献   
503.
Environmental Science and Pollution Research - The environmental situation concerning pollution by (eco)toxic and persistent trace elements in Kazakhstan has been investigated by analytical reviews...  相似文献   
504.
505.
ABSTRACT

Recent scholarship has argued that effective and credible national climate policy mixes should encompass measures that promote new low-carbon technologies alongside those instruments aimed at constraining and phasing out support for existing polluting industries. The creative and disruptive policy measures in Norway´s climate policy mix are analysed by focusing on both national and international climate mitigation efforts. Norway´s climate policy mix at home has been more ambitious in the transport sector with a growing electric vehicle market than in the energy sector where niche support and disruptive policies have remained weak. Abroad, Norway has been increasingly active in supporting new low-carbon technologies and disrupting the fossil-fuel industry, especially coal. This is explained by the consensus-seeking and oil and gas dominated small-state social-investment political economy in Norway, combined with a forward-looking foreign policy based on norm-setting and multilateralism.  相似文献   
506.

Background, aim, and scope

Over the last two decades, there has been a remarkable shift of attention to the scientific and political fundamentals of the precautionary principle. The application of this principle has become a main strategy of coping with the different forms and problems related to non-knowledge. Thus, societies are increasingly confronted with the challenging and hitherto unresolved problem of political and technological decision-making under conditions of diverging framings of non-knowledge. At present, there seems to be no generally accepted scientific or institutional approach. This is why the fundamental question of how different scientific actors define and construct evidence is not answered yet. Hence, this paper is based on the consideration that the conflicts in risk policy concerning genetically modified organisms (GMO) depend on the unresolved conflicts about the diverging scientific strategies and structures of evidence-making between the epistemic cultures involved. Thus, this study investigates two questions: (1) do the epistemic strategies of evidence-making differ systematically with the scientific actors involved in the GMO-debate? (2) What consequences emerge considering institutionalized procedures of decision-making?

Main features

This article is based on a secondary analysis of findings and perspectives reported in the literature and on the methods of qualitative social empirical research, i.e., interviews with experts. A total number of 34 interviews were conducted to explore the different strategies of handling non-knowledge and constructing evidence. Actors from science, administration, business and NGOs were interviewed. In this way, typical epistemic cultures can be described. An epistemic culture is the constellation of methodological strategies, theoretical assumptions and practical-experimental settings which define in every speciality the ways how we know what we know.

Results

There are two main results. Firstly, it was worked out that the epistemic cultures involved in the GMO-debate use rather distinct strategies to define non-knowledge and to classify evidence. There are three types of constructing evidence, which correspond to different types of epistemic cultures. Secondly, the findings imply that the intensity of the conflicts in risk policy fields like the GMO-debate is due to a lack of knowledge politics. Usually, knowledge politics is restricted to the design of institutional procedures to compile knowledge provided by experts. The institutional setting of risk analysis and risk management is based on the premise of strict separation between knowledge and power. However, inadmissible mixing-up of knowledge and power is observable.

Discussion

It seems that non-knowledge leads to an epistemic no man’s land, and, hence, hybrid regimes of knowledge emerge. These regimes are hybrid with respect to the unclear and not explicitly reflected strategies of evidence-making. By lacking of knowledge politics, this situation opens up ‘windows of opportunity’ for actors with special interests in risk policy fields like the GMO-debate. Therefore, there is a difference between the visible institutionalized structures of risk policies and the rather invisible hybrid regimes of knowledge. Structure and scope of expertise have to be reflected and new instruments of knowledge politics have to be designed.

Conclusions

Different epistemic cultures can be qualified by describing their particular strategies of evidence-making. To solve the conflicts between these strategies, a meta-expertise is needed. Besides the institutionalized settings of knowledge politics, the underlying hybrid regimes of knowledge have to be identified.

Recommendations and perspectives

The concept of epistemic cultures and their strategies of evidence-making should be investigated more explicitly with respect to other risk policy fields The analysis of hybrid regimes of knowledge should be deepened by looking at the complex interactions between institutional, discursive and practical rules affecting risk assessment.
  相似文献   
507.
知识网络是由创造、转移、吸收和应用知识的行为主体在知识的传播与交流过程中彼此联结而形成的网络结构。以国际ISI和国内VIP数据库中2000~2009年发表于生物技术领域的合著论文作者信息统计数据为数据源,基于社会网络分析的理论和方法,从国际和国内省级层面运用UCINET和Pajek软件分析知识网络的空间极化和扩散规律。总体上看网络仍处于量的扩张期,网络的稳健性正在逐步提高,网络结构开始向成熟型转变。国际层面上看,知识网络的空间极化现象明显。国内层面上看,知识网络由等级结构向扁平结构转变,空间上相应地经历了由一极向多核再向多中心发展的过程。依据知识网络空间分布特征,将知识交流区域分为知识集聚区、知识门户区、知识途径区及知识边缘区四大类型,并对我国的技术创新政策提出对策建议  相似文献   
508.
Little is known about the importance of drainage/irrigation channels and biogeochemical processes in arsenic distribution of shallow groundwaters from the Hetao basin. This investigation shows that although As concentrations are primarily dependent on reducing conditions, evaporation increases As concentration in the centre of palaeo-lake sedimentation. Near drainage channels, groundwater As concentrations are the lowest in suboxic-weakly reducing conditions. Results demonstrate that both drainage and irrigation channels produce oxygen-rich water that recharges shallow groundwaters and therefore immobilize As. Groundwater As concentration increases with a progressive decrease in redox potential along the flow path in an alluvial fan. A negative correlation between SO42− concentrations and δ34S values indicates that bacterial reduction of SO42− occurs in reducing aquifers. Due to high concentrations of Fe (>0.5 mg L−1), reductive dissolution of Fe oxides is believed to cause As release from aquifer sediments. Target aquifers for safe drinking water resources are available in alluvial fans and near irrigation channels.  相似文献   
509.
We aimed at evaluating the effect of low-level air pollution on leaf area fluctuating asymmetry (FAA) and specific leaf area (SLA) of Salix alba L., taking into account other environmental factors. Cuttings were grown in standardized conditions in the near vicinity of air quality measuring stations in Belgium. Variability of SLA and FAA between measuring stations explained 83% and 7.26%, respectively, of the total variability. FAA was not influenced by air pollution or environmental factors such as shading, herbivory, air temperature and humidity. SLA was increased by an increase in shadow, while NOx and O3 concentrations had only a marginal influence. The influence of SO2 concentration was negligible. Although our data analysis suggests a relationship between SLA and NOx/O3 concentration, the absence of a straightforward relationship between FAA and SLA and air pollution still questions the usefulness of these bio-indicators for monitoring air pollution.  相似文献   
510.
In the carbon capture and storage (CCS) chain, transport and storage set different requirements for the composition of the gas stream mainly containing carbon dioxide (CO2). Currently, there is a lack of standards to define the required quality for CO2 pipelines. This study investigates and recommends likely maximum allowable concentrations of impurities in the CO2 for safe transportation in pipelines. The focus is on CO2 streams from pre-combustion processes. Among the issues addressed are safety and toxicity limits, compression work, hydrate formation, corrosion and free water formation, including the cross-effect of H2S and H2O and of H2O and CH4.  相似文献   
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