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111.
Harnessing the economic potential of the oceans is key to combating poverty, enhancing food security, and strengthening economies. But the concomitant risk of intensified resource extraction to migratory species is worrying given these species contribute to important ecological processes, often underpin alternative livelihoods, and are mostly already threatened. We thus sought to quantify the potential conflict between key economic activities (5 fisheries and hydrocarbon exploitation) and sea turtle migration corridors in a region with rapid economic development: southern and eastern Africa. We satellite tracked the movement of 20 loggerhead (Caretta caretta) and 14 leatherback (Dermochelys coriacea) turtles during their postnesting migrations. We used movement‐based kernel density estimation to identify migration corridors for each species. We overlaid these corridors on maps of the distribution and intensity of economic activities, quantified the extent of overlap and threat posed by each activity on each species, and compared the effects of activities. These results were compared with annual bycatch rates in the respective fisheries. Both species’ 3 corridors overlapped most with longline fishing, but the effect was worse for leatherbacks: their bycatch rates of approximately 1500/year were substantial relative to the regional population size of <100 nesting females/annum. This bycatch rate is likely slowing population growth. Artisanal fisheries may be of greater concern for loggerheads than for leatherbacks, but the population appears to be withstanding the high bycatch rates because it is increasing exponentially. The hydrocarbon industry currently has a moderately low impact on both species, but mining in key areas (e.g., Southern Mozambique) may undermine >50 years of conservation, potentially affecting >80% of loggerheads, 33% of the (critically endangered) leatherbacks, and their nesting beaches. We support establishing blue economies (i.e., generating wealth from the ocean), but oceans need to be carefully zoned and responsibly managed in both space and time to achieve economic (resource extraction), ecological (conservation, maintenance of processes), and social (maintenance of alternative livelihood opportunities, alleviate poverty) objectives.  相似文献   
112.
应用PSB处理乳品厂废水的试验研究   总被引:13,自引:0,他引:13  
采用炭渣填料固定PSB混合菌膜技术,对乳品厂废水处理进行试验研究?阐述了工艺流程?工艺参数及效果分析?结果表明,出水各项指标均达到排放标准?CODCr,BOD5,SS,S2-,油类去除率分别为97%,98%,96%,86%,88%?   相似文献   
113.
建设“海上苏东”和实施百万亩滩涂工程,是实现江苏省21世纪发展战略的重大决策,在分析滩涂资源开发现状基础上,提出了及时将滩涂区位,资源优势转化为商品,经济优势的渔业生态工程,并运用生态学原理和系统分析的方法进行了总体构思,即大力发展咸淡水养殖,建立增养殖生态调控模式,开发养殖新品系三个主要方面。起步工程以引种驯养“海卿”等为主要内容,试验表明,海鲫具有优良的经济性状,适宜在咸淡水水域中生长,有望成  相似文献   
114.
Small-scale inland capture fisheries provide an important source of nutritious food, employment and income to millions of people in developing countries, particularly in rural environments where limited alternatives exist. However, the sector is one of most under-valued fisheries sectors and is increasingly experiencing environmental change. This study adopts a Sustainable Livelihoods Approach and investigates how important a fluctuating inland fishery is to livelihoods, and how local perceptions on challenges corresponds to global evidence. Through an innovative participatory method; photovoice, the lived experiences and perceptions of fishers are depicted. The findings illuminate the valuable role of the sector to food and nutrition security and the complex nexus with vulnerability to climate change. The study responds to the call for more local level assessments of the impacts of climate change on inland fisheries in data-limited environments, and the value of the sector in underpinning the Sustainable Development Goals. Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01583-1.  相似文献   
115.
对中国典型的小型焚烧设施现状和二噁英类排放进行了初步调查研究,未经处理的小型垃圾焚烧设施烟气中二噁英类毒性当量(TEQ)大于6 ng/m3,小型火化机烟气中二噁英类TEQ大于5 ng/m3.设计并检验了布袋除尘器和活性炭滤布的二噁英类去除效果.仅使用布袋除尘器二噁英类去除率不高,布袋除尘器和活性炭滤布联用可以有效去除飞灰和气相中的二噁英类,去除率达到90%左右,可达到《生活垃圾焚烧污染控制标准》(GB 18485-2001)二噁英类排放标准.  相似文献   
116.
Abstract:  The endangered population of sockeye salmon (Oncorhynchus nerka) in Cultus Lake, British Columbia, Canada, migrates through commercial fishing areas along with other, much more abundant sockeye salmon populations, but it is not feasible to selectively harvest only the latter, abundant populations. This situation creates controversial trade-offs between recovery actions and economic revenue. We conducted a Bayesian decision analysis to evaluate options for recovery of Cultus Lake sockeye salmon. We used a stochastic population model that included 2 sources of uncertainty that are often omitted from such analyses: structural uncertainty in the magnitude of a potential Allee effect and implementation uncertainty (the deviation between targets and actual outcomes of management actions). Numerous state-dependent, time-independent management actions meet recovery objectives. These actions prescribe limitations on commercial harvest rates as a function of abundance of Cultus Lake sockeye salmon. We also quantified how much reduction in economic value of commercial harvests of the more abundant sockeye salmon populations would be expected for a given increase in the probability of recovery of the Cultus population. Such results illustrate how Bayesian decision analysis can rank options for dealing with conservation risks and can help inform trade-off discussions among decision makers and among groups that have competing objectives.  相似文献   
117.
A priori assessments of a site's biophysical and socio-economic capacity for accommodating tourism are less common than tourism impact studies. A priori evaluations can provide a contextual understanding of ecological, economic and socio-cultural forces, which shape the prospects for sustainable tourism development at the host destination, and can avert adverse impacts of tourism. We conduct an a priori assessment of the biophysical environment of Pulau Banggi, in the Malaysian state of Sabah for sustainable tourism development. We characterise baseline conditions of the island's marine biodiversity, seasonality, and infrastructure. We then evaluate how existing biophysical conditions will influence options for sustainable tourism development. In particular, we suggest conditions, if there are any, which constitute a limit to future tourism development in terms of compatibility for recreation and resilience to visitor impacts. We find that the biggest constraint is the lack of adequate water and sanitation infrastructure. Blast fishing, although occurring less than once per hour, can potentially destroy the major attraction for tourists. We conclude that while Pulau Banggi possesses natural qualities that are attractive for ecotourism, financial and institutional support must be made available to provide facilities and services that will enable local participation in environmental protection and enhance prospects for future sustainable tourism.  相似文献   
118.
It is accepted that if fisheries resources are to remain renewable and able to sustain livelihoods, appropriate management practices must be implemented. Even while fisheries management grapples to resolve single-species issues, the biological and economic interactions among species mandate that to be effective, management techniques must be based on more interactive and aggregate-level analyses. In order to implement these techniques, the actual links, and the potential impact of these links, among the fisheries must be established. Vector autoregression (VAR) analysis has the potential to play an increasingly important role in ecosystem modelling for fisheries management. This study uses VAR analysis to demonstrate the quantitative impact of certain ecosystem changes on the productivity of the carite, honey shrimp and croaker fisheries of the Gulf of Paria, Trinidad, in the particular context of the ecosystem dynamics of trophic linkages, bycatch and multispecies fisheries. Four VAR models are constructed to investigate the extent to which these factors affect the production of the selected fisheries, and to evaluate the management implications of these linkages. The empirical analysis is further evidence that, if sustainable management of fishery resources is to be achieved, management practices based on more multi-species, ecosystem approaches must replace the traditional, single-species management techniques.  相似文献   
119.
Illegal, unregulated, and unreported (IUU) fishing poses a major threat to effective management of marine resources, affecting biodiversity and communities dependent on these coastal resources. Spatiotemporal patterns of industrial fisheries in developing countries are often poorly understood, and global efforts to describe spatial patterns of fishing vessel activity are currently based on automatic identification system (AIS) data. However, AIS is often not a legal requirement on fishing vessels, likely resulting in underestimates of the scale and distribution of legal and illegal fishing activity, which could have significant ramifications for targeted enforcement efforts and the management of fisheries resources. To help address this knowledge gap, we analyzed 3 years of vessel monitoring system (VMS) data in partnership with the national fisheries department in the Republic of the Congo to describe the behavior of national and distant-water industrial fleets operating in these waters. We found that the spatial footprint of the industrial fisheries fleet encompassed over one-quarter of the Exclusive Economic Zone. On average, 73% of fishing activity took place on the continental shelf (waters shallower than 200 m). Our findings highlight that VMS is not acting as a deterrent or being effectively used as a proactive management tool. As much as 33% (13% on average) of fishing effort occurred in prohibited areas set aside to protect biodiversity, including artisanal fisheries resources, and the distant-water fleet responsible for as much as 84% of this illegal activity. Given the growth in industrial and distant-water fleets across the region, as well as low levels of management and enforcement, these findings highlight that there is an urgent need for the global community to help strengthen regional and national capacity to analyze national scale data sets if efforts to combat IUU fishing are to be effective.  相似文献   
120.
Governance regimes that assign exclusive access to support collective action are increasingly promoted to manage common-pool resources under the premise that they foster environmental stewardship. However, experimental evidence linked to existing policies that support this premise is lacking. Overlapping access policies in small-scale fisheries provide a unique opportunity to test the effects of access regimes on users’ stewardship behaviors. We performed a lab-in-the-field experiment to assess how fishers’ previous experience with access regimes relates to compliance and peer enforcement (n = 120). Fishers’ compliance and peer-enforcement decisions were compared in a common-pool-resource game. Treatments differed in framing to represent exclusive access and pseudo-open access regimes, both of which fishers face in real life. To contrast behavior in the game with real-life observations, we compared fishers’ associations that have shown relatively high and low management performance under exclusive access policies. Compliance and peer enforcement were higher under the exclusive access treatment than under the pseudo-open access treatment only for fishers’ associations with high management performance in real life. Behaviors in the game reflected differences between associations in real life. Our results support previous research on ocean governance by experimentally assessing the role of access regimes in determining users’ stewardship and suggest potential mechanisms for stewardship internalization.  相似文献   
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