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101.
Two harbor porpoises in a floating pen were subjected to five pure tone underwater signals of 70 or 120kHz with different signal durations, amplitudes and duty cycles (% of time sound is produced). Some signals were continuous, others were intermittent (duty cycles varied between 8% and 100%). The effect of each signal was judged by comparing the animals' surfacing locations and number of surfacings (i.e. number of respirations) during test periods with those during baseline periods. In all cases, both porpoises moved away from the sound source, but the effect of the signals on respiration rates was negligible. Pulsed 70kHz signals with a source level (SL) of 137dB had a similar effect as a continuous 70kHz signal with an SL of 148dB (re 1muPa, rms). Also, a pulsed 70kHz signal with an SL of 147dB had a much stronger deterring effect than a continuous 70kHz signal with a similar SL. For pulsed 70kHz signals (2s pulse duration, 4s pulse interval, SL 147dB re 1muPa, rms), the avoidance threshold sound pressure level (SPL), in the context of the present study, was estimated to be around 130dB (re 1muPa, rms) for porpoise 064 and around 124dB (re 1muPa, rms) for porpoise 047. This study shows that ultrasonic pingers (70kHz) can deter harbor porpoises. Such ultrasonic pingers have the advantage that they do not have a "dinner bell" effect on pinnipeds, and probably have no, or less, effect on other marine fauna, which are often sensitive to low frequency sounds.  相似文献   
102.
This paper analyses effects of a shift from input to output controls in Australia's Southern Shark Fishery. We show that the use of two management tools—individual transferable quotas and a “partnership approach”—was flawed and argue that primary contributing causes were the unjustified expectation that quota management would serve as a ‘technical fix’ to a variety of presumed problems, the discounting of social effects and the extreme lack of stability in the organizational structure within which this fishery was situated.  相似文献   
103.
The paper reviews and summarises the literature on regulatory enforcement in fisheries. The focus is on the theoretical literature. First, some of the main contributions from the general economic literature of law enforcement are presented, along with extensions that are considered relevant to the study of fisheries law enforcement. Second, a review of the economic literature of law enforcement applied to the study of fisheries is provided. Finally, the paper presents gaps in the fisheries economics literature on regulatory enforcement and offers some possibilities for future work.  相似文献   
104.
The relationship between stakeholder participation (SP) and the ecosystem-based approach to fisheries management (EBAFM) is often taken for granted, but is actually very complicated. The literature reveals five possible interpretations of this relationship: that they are (1) logically linked; (2) ethically linked; (3) instrumentally linked; (4) complementarily linked and (5) antagonistically linked. We examine these five formulations in the light of recent research on interactions between fisheries and their environment and conclude that the SP/EBAFM relationship manifests itself as predominantly instrumental in character.  相似文献   
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Brazil is the first major developing country to pledge for absolute reductions in greenhouse gas emissions. This article explores the extent to which fiscal policies could contribute to this reduction and to greening the Brazilian economy. It was found that the use of green fiscal policies is at an early stage in Brazil, but a growing number of measures have been adopted in recent years led by subnational-level policies. An econometric analysis of 24 Brazilian manufacturing sectors for the years 2001–2008 shows that some fiscal instruments, such as low-cost (subsidized) finance for innovation and fiscal incentives for sustainable practices, have been effective in inducing green innovation. However, less than 14% of more than 100 thousand companies included in the study have adopted greener technologies. Even though Brazilian green fiscal policies have been rather uncoordinated and ad hoc, their significant impact on the uptake of green technologies indicates these can play an important role in a transition to a green economy.

POLICY RELEVANCE

Faced with the challenge of reducing its greenhouse gas emissions in absolute terms, Brazil now needs to put in place policies to help deliver the country’s pledge. This article analyses which fiscal policies should be adopted and how these policies could form part of a low carbon policy framework in the country. Among our policy-relevant findings is that subnational green fiscal policies are relatively less complex to introduce and encourage uptake of green technologies. Thus, they could be an entry point to a wider green fiscal policy strategy. We also found that fiscal incentives for green innovation projects can present more than proportional impact on the uptake of green technologies owing to positive feedbacks, increasing returns to scale and spill-overs. These are attractive features of green innovations to developing countries in addition to environmental benefits, as they favour the accumulation of indigenous technological capabilities that are critical for long-term technological and economic development. These lessons learned from green fiscal policies in Brazil are applicable to other developing countries.  相似文献   

109.
Eco-certifications have become an important site of power struggles in commodity sectors such as forestry, fisheries, aquaculture, palm oil, and soy. In each, multiple eco-certification initiatives have been developed and resisted through interactions among non-governmental organizations, governments, and commercial actors. This paper contributes to understanding how power is embodied in certifications by exploring how territoriality manifests in the international struggle over defining what products are ‘sustainable’ and which producers will have access to markets that require ‘sustainable’ products. Focusing on the wild capture fisheries sector in which the non-governmental Marine Stewardship Council (MSC) administers the preeminent eco-certification initiative, we explore the emergence of new fisheries eco-certification initiatives in Japan, Iceland, Alaska, Canada, and the US that insist there is no transnational monopoly on judgments over fisheries sustainability. We argue that these new eco-certifications attempt to defend and embed territorial social and regulatory relations of production within the contested domain of transnational sustainability governance. The initiatives accommodate both the territorially embedded material interests, institutions, and discursive strategies of producers (and their state supporting agencies) and transnationally embedded governance norms for assessing and communicating sustainability. They also counter the globally applicable institutions of the MSC in favor of making space for state and non-state actors to contend with demands for sustainability in the global seafood market by combining place-specific attributes with transnational governance norms.  相似文献   
110.
This paper highlights the tension between advocacy for ‘Blue growth’ in maritime policy and efforts to safeguard future economic growth via the Marine Strategy Framework Directive. In 2015, policy-makers withdrew three of four proposed Marine Conservation Zones (MCZs) in the Irish Sea from consideration for designation, due to concerns that they could significantly impact on the fisheries sector in Northern Ireland because they overlap with prawn fishing grounds in the Irish Sea. Although research has quantified the potential impact upon fishing vessels, none has quantified the impact upon the fisheries sector nor assessed the significance of this impact. Arguably, MCZ designations (or lack thereof) based on the ‘significance’ of an impact require robust underpinning evidence. This paper reports the findings of an Economic Impact Assessment, which has quantified the impact of a decline in landings upon the Northern Ireland fisheries sector and regional economy (data which is currently absent from the evidence base for the MCZ designation process in England). It finds that this will incur job losses in three fishing ports in Northern Ireland, but is unlikely to have a significant impact upon Northern Ireland's fisheries sector and regional economy in terms of jobs and Gross Value Added (GVA). In the worst case, the resulting economic impact is a decrease of £1.05–1.12 m/year GVA in Northern Ireland, which is 1.1% of the contribution of fishing and fish processing to the regional economy. Economic significance assessments, using this methodology, may be useful in supporting the evidence base underpinning MCZ designation and other aspects of marine planning.  相似文献   
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