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101.
Hot spots in Brazil include a variety of ecosystems, such as mangroves, forests, and the Brazilian savannah, locally called cerrado. Some of the rural populations in these hot spots are the caiçaras in SE Atlantic Forest coast, and the caboclos in the Amazon. In this study, we are concerned especially with the knowledge of caiçaras and caboclos, associated with practices that might have implications for management. Data were gathered through interviews with adults at the various communities studied, and through systematic observations, including samples of fishing trips and the mapping of fishing spots used in the Atlantic Forest coast. The use of resources from the surrounding vegetation includes collection of plants, cultivated fruit gardens, the swidden system, and a careful and managed extraction of fibres. Among animal resources, food taboos seem to be useful practices that might contribute to the maintenance of local natural resources. Potential management practices should be locally developed, such as the informal division of fishing spots in Atlantic Forest sites, and the maintenance of the diversity of cassava varieties in both the Atlantic Forest and Amazonian areas.  相似文献   
102.
This paper explores corruption in global fisheries. While reducing corruption is critical for the effective management of the fisheries sector and the fulfilment of the UN's sustainable development goals (SDGs, and SDGs14 and 16 in particular), to do so, it is necessary to first have a systematic and comprehensive understanding of what corruption is and how it is manifested in the sector. There is literature on illegal, unregulated and unreported (IUU) fishing, but not much on corruption. The paper proposes an analytical framework and applies it with six revelatory cases to improve the conceptual clarity of corruption in fisheries. Specific corruption problems found in licensing, negotiating access agreements, lax enforcement, extortion, political corruption, money laundering and tax manipulation, human trafficking, etc. can therefore be better identified through this analysis, which lays a base for systematic responses to tackling corruption in fisheries and accordingly furthering the sustainable development of the sector.  相似文献   
103.
The sinking of the Prestige oil tanker on 18 November 2002 off the coast of Galicia, Spain, had important economic, environmental and social ramifications. The aim of this paper is to carry out an initial analysis of the costs related to a halt in fishing activities in Galicia between November 2002 and December 2003. This involves three different steps: an assessment of the cost of the preventative and palliative measures introduced by Spanish public administrations (compensation for affected fishermen and shellfish fisherman); an indirect evaluation of the implications of the disaster (via a study of data on production); and a direct appraisal of the economic impact of the event (reduction in income), using questionnaires completed by a representative sample of fishermen and shellfish fisherman. The results obtained from these three methods of estimating losses are compatible. By December 2003, losses to the Galician fishing sector stood at an estimated EUR 76 million.  相似文献   
104.
105.
The effects of fisheries on marine ecosystems, and their capacity to drive shifts in ecosystem states, have been widely documented. Less well appreciated is that some commercially valuable species respond positively to fishing‐induced ecosystem change and can become important fisheries resources in modified ecosystems. Thus, the ecological effects of one fishery can unintentionally increase the abundance and productivity of other fished species (i.e., cultivate). We reviewed examples of this effect in the peer‐reviewed literature. We found 2 underlying ecosystem drivers of the effect: trophic release of prey species when predators are overfished and habitat change. Key ecological, social, and economic conditions required for one fishery to unintentionally cultivate another include strong top–down control of prey by predators, the value of the new fishery, and the capacity of fishers to adapt to a new fishery. These unintended cultivation effects imply strong trade‐offs between short‐term fishery success and conservation efforts to restore ecosystems toward baseline conditions because goals for fisheries and conservation may be incompatible. Conflicts are likely to be exacerbated if fisheries baselines shift relative to conservation baselines and there is investment in the new fishery. However, in the long‐term, restoration toward ecosystem baselines may often benefit both fishery and conservation goals. Unintended cultivation can be identified and predicted using a combination of time‐series data, dietary studies, models of food webs, and socioeconomic data. Identifying unintended cultivation is necessary for management to set compatible goals for fisheries and conservation. Cultivo Accidental, Líneas de Base Cambiantes y el Conflicto entre los Objetivos para las Pesquerías y la Conservación  相似文献   
106.
Ecotourism can incentivize social and environmental benefits through marine conservation, in parallel with efforts to better manage fisheries, coastal development, and other human pressures. In Mexico's Gulf of California and Baja California Peninsula (GCBP), marine ecosystems support tourism activities in many communities, but to date there have been no region-wide studies to estimate their benefits or identify key species. Based on data collected in this study, each year nature-based marine tourism in the GCBP results in 896,000 visits, US$518 million in expenditures and at least 3,575 direct jobs from formal operations. In interviews with operators, over 40 species groups were named as important; sea lions, whale sharks, whales, and marlin were the highest ranked, highlighting the importance of ecosystem-wide health for nature-based tourism sustainability. Local employment and the ability to make economic and conservation goals compatible were noted by operators as significant opportunities provided by nature-based marine tourism; challenges included pollution and declines in ecosystem health, a lack of infrastructure, poor resource management policies, and high operating costs. As nature-based marine tourism expands, a wider transition to true ecotourism, a focus on equitable benefits and collaboration between stakeholders and a cross-scale and ecosystem approach to management will be vital for achieving potential sustainable social, ecological and economic benefits.  相似文献   
107.
Approximately 25% of globally reported shark catches occur in Atlantic pelagic longline fisheries. Strong declines in shark populations have been detected in the North Atlantic, whereas in the South Atlantic the situation is less clear, although fishing effort has been increasing in this region since the late 1970s. We synthesized information on shark catch rates (based on 871,177 sharks caught on 86,492 longline sets) for the major species caught by multiple fleets in the South Atlantic between 1979 and 2011. We complied records from fishing logbooks of fishing companies, fishers, and onboard observers that were supplied to Brazilian institutions. By using exploratory data analysis and literature sources, we identified 3 phases of exploitation in these data (Supporting Information). From 1979 to 1997 (phase A), 5 fleets (40 vessels) fished mainly for tunas. From 1998 to 2008 (phase B), 20 fleets (100 vessels) fished for tunas, swordfishes, and sharks. From 2008 to 2011 (phase C), 3 fleets (30 vessels) fished for multiple species, but restrictive measures were implemented. We used generalized linear models to standardize catch rates and identify trends in each of these phases. Shark catch rates increased from 1979 to 1997, when fishing effort was low, decreased from 1998 to 2008, when fishing effort increased substantially, and remained stable or increased from 2008 to 2011, when fishing effort was again low. Our results indicate that most shark populations affected by longlines in the South Atlantic are currently depleted, but these populations may recover if fishing effort is reduced accordingly. In this context, it is problematic that comprehensive data collection, monitoring, and management of these fisheries ceased after 2012. Concurrently with the fact that Brazil is newly identified by FAO among the largest (and in fastest expansion) shark sub‐products consumer market worldwide.  相似文献   
108.
A comprehensive list of planning criteria for optimizing compliance in Marine Protected Areas (MPAs) was compiled and used to compare the views of recreational fishers and compliance officers for facilitating voluntary compliance in the Port Stephens - Great Lakes Marine Park (PSGLMP). Expert working groups were tasked separately with: 1) criteria identification and weighting; 2) scoring of no-take zones; 3) prioritizing and determining uncertainty; and 4) analysis of results and sensitivity testing. Multi-Criteria Analysis (MCA) revealed that both groups had similar perspectives and recommendations, despite weighting the individual planning criteria differently. Significantly, "manageability" scores for no-take zones from MCA appeared to correlate well with past numbers of enforcement actions recorded for each zone. This provides empirical evidence that adopting manageability criteria during the planning of MPAs could lead to a marked increase in voluntary compliance. As a result, greater consideration to compliance planning during MPA design and zoning is recommended in order to optimize voluntary compliance. Whilst the majority of no-take zones in the PSGLMP case study were evaluated as being relatively effective in terms of optimizing voluntary compliance, there remains considerable potential to improve design, management and use of the poorer performing zones. Finally, the study highlighted the value of recreational fisher engagement in MPA planning processes to maximize voluntary compliance and manageability.  相似文献   
109.
In this paper we study optimal harvesting of the Norwegian spring-spawning herring stock. The biological model is described by a discrete time age-structured model. The optimal harvesting patterns are studied numerically and the results show that when using a linear cost function and constant price in the optimisation model, the optimal harvesting pattern is pulse fishing. However, optimal constant fishing effort gives only slightly lower profit. Moreover, when price is made responsive to harvest the optimal harvesting strategy is substantially smoothed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
110.
Maritime transport has been playing a decisive role in global trade. Its contribution to the air pollution of the sea and coastal areas has been widely recognized. The air pollutant emission inventories of several harbors in China have already been established. However,the emission factors of local ships have not been addressed comprehensively, and thus are lacking from the emission inventories. In this study, on-board emission tests of eight diesel-powered offshore fishing ships were conducted near the coastal region of the northern Yellow Bo Sea fishing ground of Dalian, China. Results show that large amounts of fine particles( 0.5 μm, 90%) were found in maneuvering mode, which were about five times higher than those during cruise mode. Emission rates as well as emission factors based on both distance and fuel were determined during the cruise and maneuvering modes(including departure and arrival). Average emission rates and distance-based emission factors of CO, HC and PM were much higher during the maneuvering mode as compared with the cruise mode. However, the average emission rate of Nitrous Oxide(NOx) was higher during the cruise mode as compared with the maneuvering modes. On the contrary, the average distance-based emission factors of NOxwere lower during the cruise mode relative to the maneuvering mode due to the low sailing speed of the latter.  相似文献   
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