首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Sustainable fisheries management into the future will require both understanding of and adaptation to climate change. A risk management approach is appropriate due to uncertainty in climate projections and the responses of target species. Management strategy evaluation (MSE) can underpin and support effective risk management. Climate change impacts are likely to differ by species and spatially. We use a spatial MSE applied to a multi-species data-poor sea cucumber/béche-de-mer fishery to demonstrate the utility of MSE to test the performance of alternative harvest strategies in meeting fishery objectives; this includes the ability to manage through climate variability and change, and meeting management objectives pertaining to resource status and fishery economic performance. The impacts of fishing relative to the impacts of climate change are distinguished by comparing future projection distributions relative to equivalent no-fishing no-climate-change trials. The 8 modelled species exhibit different responses to environmental variability and have different economic value. Status quo management would result in half the species falling below target levels, moderate risks of overall and local depletion, and significant changes in species composition. The three simple strategies with no monitoring (spatial rotation, closed areas, multi-species composition) were all successful in reducing these risks, but with fairly substantial decreases in the average profit. Higher profits (for the same risk levels) could only be achieved with strategies that included monitoring and hence adaptive management. Spatial management approaches based on adaptive feedback performed best overall.  相似文献   

2.
Globally, small-scale fisheries are critical for livelihoods and food security yet face increasing uncertainty and variability from processes such as overfishing, globalization, and climate change. Enhancing the number of options for human response through increased access to marine resources, diverse livelihood approaches, and generalist fishing strategies may attenuate the negative effects of change and disturbance. My research explores the relative importance of diversification strategies for achieving resilient small-scale fishing communities and cooperatives of Baja California Sur, Mexico. Specifically, interview data and long-term catch and economic data were used to develop an economic metric of resilience, in addition to income diversification indices, for fishing cooperatives. Fishing cooperative characteristics and environmental conditions were then evaluated as possible predictors of cooperatives’ relative ability to diversify. I found that while diversification was important for risk mitigation and stabilizing income, the ability of cooperatives to specialize during favorable conditions may be important for poverty reduction and wealth accumulation. Thus, the flexibility to move across fishing strategies given changing environmental conditions is important for the adaptive capacity of small-scale fishing cooperatives. My findings will contribute to a better understanding of the institutional arrangements that promote a resilient small-scale fishery, and therefore, will be invaluable for practitioners of small-scale fisheries.  相似文献   

3.
Environmental NGOs are increasingly called upon to respect human rights when undertaking conservation programs. Evaluating a family planning program running alongside marine management measures in Madagascar, we find that family planning services provided by an environmental NGO can support women’s reproductive rights. Family planning services allow the option of smaller families, and give more time to work, increased income and better health. These benefits do not translate into increased support for, or participation in, marine management, however, and women who are able to work more are typically fishing more. We identify patriarchal norms as a key factor preventing the family planning programme from manifesting in improved resource stewardship, limiting opportunities for women to participate fully in resource management meetings and diversify their livelihood outside traditional tasks, including fishing. We propose that a successful human rights-based approach must be more comprehensive, targeting multiple rights and challenging existing institutions and power structures.  相似文献   

4.
Social Change, Ecology and Climate in 20th-Century Greenland   总被引:5,自引:1,他引:4  
Two great transitions, from seal hunting to codfishing, then from cod fishing to shrimp, affectedpopulation centers of southwest Greenland during the20th century. These economic transitionsreflected large-scale shifts in the underlying marineecosystems, driven by interactions between climate andhuman resource use. The combination of climaticvariation and fishing pressure, for example, provedfatal to west Greenland's cod fishery. We examine thehistory of these transitions, using data down to thelevel of individual municipalities. At this level,the uneven social consequences of environmental changeshow clearly: some places gained, while others lost. Developments in 20th-century Greenland resemblepatterns of human-environment interactions in themedieval Norse settlements, suggesting some generalpropositions relevant to the human dimensions ofclimatic change.  相似文献   

5.
We investigate the interactions between anthropogenic climate change, socioeconomic developments and tuna fishery management strategies. For this purpose, we use the APECOSM-E model to map the effects of climate change and commercial fishing on the distribution of skipjack tuna biomass in the three oceans, combined with a new bioeconomic module representing the rent or profit of skipjack fisheries. For forcing, we use Representative Concentration Pathway (RCP) 8.5, the highest emission scenario for greenhouse gas concentrations presented in the IPCC’s Fifth Assessment Report (AR5), and the IPCC Socioeconomic Shared Pathway (SSP) 3, which is characterized by low economic development and a strong increase in the world population. We first investigate the impact of climate change on regional skipjack abundance, catches and profits in three oceans (Atlantic, Indian and Pacific) in 2010, 2050 and 2095. We then study the effects of three management strategies (maximum sustainable yield or MSY, maximum economic yield or MEY, and zero rent or ZR) on the future distribution of fishing fleets between oceans and on global economic rent.Our model projections for 2050 and 2095 show an increase in global skipjack biomass compared to 2010 and major changes in its distribution, impacting local and regional fishing efforts. The Pacific Ocean will continue to dominate the skipjack market.In our modeling of management strategies, the currently predominant MSY strategy would have been unprofitable in 2010, due to a decreased catch per unit effort (CPUE). In the future, however, technological developments should increase fishing efficiency and make MSY profitable.In all the scenarios, a MEY strategy is more profitable than MSY but leads to the lowest catches and the highest prices. This raises ethical questions in a world where food security may become a top priority.In the scenarios where MSY generates an economic loss (e.g. 2010), a ZR strategy allows global stocks to be exploited at high but still profitable levels. Conversely, in the scenarios where MSY is profitable, (e.g. 2095) ZR leads to overfishing and smaller global catches.We conclude that the most appropriate management strategy at any time is likely to change as environmental and socioeconomic conditions evolve. The decision to follow one or other strategy is a complex one that must be regularly reviewed and updated.  相似文献   

6.
全球变化导致极端天气事件频发,尤其是高温热浪严重影响我国农业生态系统及人类健康。关于热浪事件的定义一直存在着许多争议,对热浪变化趋势空间分布特征的认识有待进一步提高。本文使用气温日较差、绝对温度与相对温度相结合的热浪指标,基于9个CMIP6气候模式的多模式集合结果,评估了可持续发展情景(SSP1-2.6)、中度发展情景(SSP2-4.5)及常规排放情境(SSP5-8.5)下未来中国高温热浪事件的时空分布及变化特征。结果表明:(1)SSP1-2.6情景下未来热浪事件在2050年前后达到顶峰,之后趋于稳定,而在SSP2-4.5情景下,热浪频次、日数及最长持续时间均呈现上升态势,SSP5-8.5情景下热浪的增长趋势及严重程度均为最高;(2)华南、华中地区未来面临更大的热浪风险,SSP5-8.5情景下的热浪频次及强度约是SSP1-2.6的2倍及以上,SSP2-4.5约是SSP1-2.6的1.5倍;(3)西部干旱/半干旱地区、内蒙古东部干旱地区出现较大范围的热浪,结合本文中热浪定义,预示着夜间变暖是全球变暖的一个重要特征。研究结果有助于理解可持续发展、中等强迫情景下我国未来的热浪频次和强度的变化特征,为区域发展节能减排方案的制定提供有效参考。  相似文献   

7.
Individual mobility – moving between and within different geographic regions – represents an adaptation strategy of natural resource users worldwide to cope with sudden and gradual changes in resource abundances. This work traces the recent history of Peruvian small-scale fishers’ migration, and particularly analyses the spatial mobility patterns of resource users along the Peruvian coastline in the aftermath of the coastal El Niño 2017. In February-March 2017, this event caused extraordinary heavy rains and a rise in water temperatures along the coast of northern Peru, inducing negative consequences for the small-scale fisheries and scallop (Argopecten purpuratus) aquaculture sectors, both representing important socio-economic activities in the region. Responses of local resource users to these changes were highly diverse, with a great number of people leaving the region in search for work in fishing and non-fishing activities. With a particular emphasis on the province of Sechura, this work attempts to shed light on how and why migration flows differ for fishers and scallop farmers and to explore future pathways in the context of post-disturbance recovery. About one year after the disturbance event, the small-scale fishery operated almost on a regular scale, while the aquaculture sector still struggled towards pre-El Niño conditions, reflected, for example, in a higher percentage of persons engaging in other economic activities within and outside the region. The results of this study demonstrate the importance of human movement and translocal social networks emerging in moments of crisis and should be considered for future development of long-term management strategies incorporating increasing interconnectedness of places on different scales in the face of future disturbance events. Understanding adaptation strategies of resource users in this particular social-ecological setting will further serve to inform other coastal systems prone to (re-occurring) environmental change by highlighting the diversity of socio-economic and natural drivers that can stipulate mobility and affect adaptive capacity of resource users.  相似文献   

8.
Heatwave intensity and frequency are predicted to increase in the coming years, and this will bear adverse consequences to the environmental well-being and the socio-economic fabric in urbanized areas. The hazardous combination of increased heat storage and reduced water retention capacities of the land surface make the urban areas warmer than the surrounding rural areas in what is commonly known as the urban heat island (UHI) effect. The primary motives of this study are to quantify the interaction of this city-scale UHI with synoptic-scale heatwave episodes and to analyze the factors that mediate this interaction. A modified version of the Weather Research and Forecasting model (WRF) is utilized to simulate two heatwave episodes in New York City. The land surface scheme in the default WRF model is modified to better represent the surface to atmosphere exchanges over urban areas. Our results indicate that during the heatwave episodes, the daily-averaged UHI in NYC increased by 1.5 K. Furthermore, most of this amplification occurs in the mid-afternoon period when the temperatures peak. Wind direction and urban-rural contrasts in available energy and moisture availability are found to have significant and systematic effects on the UHI, but wind speed plays a secondary role.  相似文献   

9.
An existing Ecopath with Ecosim (EwE) model for the Central North Pacific was updated and modified to focus on the area used by the Hawaii-based pelagic longline fishery. The EwE model was combined with output from a coupled NOAA Geophysical Fluid Dynamics Laboratory climate and biogeochemical model to investigate the likely ecosystem impacts of fishing and climate-induced primary productivity changes. Four simulations were conducted based on 2 fishing effort and climate scenarios from 2010 to 2100. Modeled small and large phytoplankton biomass decreased by 10 % and 20 % respectively, resulting in a 10 % decline in the total biomass of all higher trophic level groups combined. Climate impacts also affected the Hawaii longline fishery, with a 25–29 % reduction in modeled target species yield. Climate impacts on the ecosystem and the fishery were partially mitigated by a drop in fishing effort. Scenarios with a 50 % reduction in fishing effort partially restored longline target species yield to current levels, and decreased longline non-target species yield. These model results suggest that a further reduction in fishery landings mortality over time than the 2010 level may be necessary to mitigate climate impacts and help sustain yields of commercially preferred fish species targeted by the Hawaii longline fishery through the 21st century.  相似文献   

10.
A bioeconomic model of key fisheries of the Barents Sea is run with scenarios generated by an earth system model of intermediate complexity to assess how the Barents Sea fisheries of cod (Gadus morhua) and capelin (Mallotus villosus) are affected by changes in the Atlantic thermohaline circulation (THC) arising from anthropogenic climate change. Changes in hydrographic conditions have an impact on recruitment success and survival rates, which constitute a lasting effect on the stocks. The economic development of the fisheries is determined for the 21st century, considering a purely stock size based and a coupled stock size-hydrography based harvesting strategy. Results show that a substantial weakening of the THC leads to impaired cod stock development, causing the associated fishery to become unprofitable in the long run. Simultaneous improvements in capelin stock development help the capelin fishery, but are insufficient to offset the losses incurred by the cod fishery. A comparison of harvest strategies reveals that in times of high variability in stock development, coupled stock size-hydrography based management leads to more stable economic results of these fisheries than the stock size based fishing strategy.  相似文献   

11.
Climate change-driven alterations in storm frequency and intensity threaten the wellbeing of billions of people who depend on fisheries for food security and livelihoods. Weather conditions shape vulnerability to both loss of life and reduced fishing opportunities through their influence on fishers' daily participation decisions. The trade-off between physical risk at sea and the economic rewards of continued fishing under adverse weather conditions is a critical component of fishers’ trip decisions but is poorly understood. We employed a stated choice experiment with skippers from a temperate mixed-species fishery in southwest England to empirically assess how fishers trade off the risks from greater wind speed and wave height with the benefits of expected catch and prices. Technical fishing and socio-economic data were collected for individual fishers to identify the factors influencing trade-off decisions. Fishers preferred increased wind speed and wave height up to a threshold, after which they became increasingly averse to worsening conditions. Fishing gear, vessel length, presence of crew, vessel ownership, age, recent fishing success and reliance on fishing income all influenced the skippers’ decisions to go to sea. This study provides a first insight into the socio-economic, environmental, and technical fishing factors that can influence the sensitivity of individual fishers to changing storminess. These insights can help to inform fisheries climate vulnerability assessments and the development of adaptation measures.  相似文献   

12.
付桂琴  陆倩  张亚男 《气象学报》2022,80(3):403-409
评价高温、热浪、闷热不同热感天气暴露对心脑血管疾病死亡人数的影响。采用广义相加模型(GAM)、平滑曲线阈值效应方法,在控制了时间序列长期趋势、季节效应、节假日效应的混杂影响后,分析了2010—2016年的6—8月石家庄高温、热浪、闷热不同热感天气暴露对心脑血管疾病死亡人数的影响,并分析了男女性别的分人群效应。研究期间收集到心脑血管疾病死亡总计6552人,日均死亡10.2人,日死亡最多为40.0人。对应期间出现高温日98 d,热浪日58 d,闷热日79 d。相对于非高温、热浪、闷热日,高温、热浪、闷热天气对心脑血管疾病死亡人数影响的相对危险度分别为1.086(95%置信区间(95%CI):1.013—1.164)、1.252(95%CI:1.101—1.442)、1.100(95%CI:1.020—1.185),其最大滞后效应分别为3 d、1 d、0 d,对应死亡人数增加的风险分别为12.2%、31.8%、10.0%,且对女性的影响风险均大于男性。高温、热浪、闷热天气均可导致心脑血管疾病死亡风险的增加,归因滞后1 d热浪死亡的风险最大,归因闷热天气死亡的风险未发现滞后效应,建议依据不同热感天气有针对性地建立健康风险管理和应对机制。   相似文献   

13.
The Code of Conduct for Responsible Fisheries developed in 1995 by the Food and Agriculture Organization (FAO) of the United Nations includes a set of recommendations for reducing the negative impacts of fishing activities on marine ecosystems. The Code is widely believed to be an important tool for fisheries management and, although the Code is voluntary, all stakeholders concerned with the management and development of fisheries, and conservation of fishery resources, are actively encouraged to implement it. Previous analysis at global scale showed widespread low compliance with the Code of Conduct that may be partly due to a lack of empirical support for the overall ecological benefits of adhering to the Code. Here we evaluated these ecological effects by comparing compliance with the Code to changes in five ecological indicators that quantify the ecosystem effects of fishing. We used the loss in production index and the related probability of sustainable fishing index, the mean trophic level of the catch, total catches, and the primary production required to sustain the catch. We also tested if regional differences and development status of countries influenced the results of ecological indicators. Results indicate that countries with higher levels of compliance with the FAO Code of Conduct in 2008 experienced a decrease in the Loss in Production index and an increase in fisheries sustainability from the 1990s to 2000s. We conclude that better implementation of the Code of Conduct may have had overall positive ecological effects with time. A significant decrease in total catch and primary production required with higher compliance was also observed. While a significant increase in ecosystem sustainability was observed after a decade of adoption of the Code at high levels of compliance, further ecosystem degradation had taken place where compliance with the Code was below a given threshold (4, from a ranking of 0–10). Therefore, since compliance with the Code is still low or very low worldwide, these results may encourage individual countries to adopt well-established fishery management measures in order to increase the ecological sustainability of marine resources.  相似文献   

14.
A review of case law and other documentation of human rights issues in fishing communities highlights forced evictions, detention without trial, child labour, forced labour and unsafe working conditions, and violence and personal security, including gender-based violence, as key areas of concern. We argue that human rights violations undermine current attempts to reform the fisheries sector in developing countries by increasing the vulnerability and marginalization of certain groups. Citing cases from India, the Philippines, Cambodia, and South Africa, we show how human rights advocacy can be an effective element of support for development in fisheries. Finally, we outline how fisheries reform can better address human rights issues as an essential complement to the equitable allocation of fishing rights, contributing to improved resource management and human wellbeing.  相似文献   

15.
Coral reefs support the livelihood of millions of people especially those engaged in marine fisheries activities. Coral reefs are highly vulnerable to climate change induced stresses that have led to substantial coral mortality over large spatial scales. Such climate change impacts have the potential to lead to declines in marine fish production and compromise the livelihoods of fisheries dependent communities. Yet few studies have examined social vulnerability in the context of changes specific to coral reef ecosystems. In this paper, we examine three dimensions of vulnerability (exposure, sensitivity, and adaptive capacity) of 29 coastal communities across five western Indian Ocean countries to the impacts of coral bleaching on fishery returns. A key contribution is the development of a novel, network-based approach to examining sensitivity to changes in the fishery that incorporates linkages between fishery and non-fishery occupations. We find that key sources of vulnerability differ considerably within and between the five countries. Our approach allows the visualization of how these dimensions of vulnerability differ from site to site, providing important insights into the types of nuanced policy interventions that may help to reduce vulnerability at a specific location. To complement this, we develop framework of policy actions thought to reduce different aspects of vulnerability at varying spatial and temporal scales. Although our results are specific to reef fisheries impacts from coral bleaching, this approach provides a framework for other types of threats and different social-ecological systems more broadly.  相似文献   

16.
Over its 17 years, the UN's Global Environment Facility (GEF) has allocated US $7.5 billion intended to develop and implement scientifically and socially credible solutions to key global environmental problems such as climate change, biological diversity loss and degradation of transboundary aquatic systems. We studied 906 GEF projects to analyse the challenges that it is facing in delivering solutions that are likely to be sustainable in the long-term. The research included desk reviews of relevant documents and follow-up interviews with a wide range of stakeholders. Some of the challenges the GEF faces are deeply rooted in temporal and spatial mismatches of scale between human economies and their environmental consequences and the strongly sectoral way current society is managed. We conclude that the GEF obtained impressive results for tackling problems of limited complexity and easily quantified benefits but progress is slower on more complex and less tangible problems impeding sustainable development. Potentially, the GEF could enable adaptive management through a ‘learning by doing’ process, transforming it into an innovative mechanism for delivering global benefits. Continued emphasis on ‘easy wins’ would not allow it to achieve this goal.  相似文献   

17.
Illegal, unregulated and unreported (IUU) fishing is a challenging form of non-compliance in many marine ecosystems. IUU fishing has attracted substantial political attention in the Southern Ocean, where a series of crises created windows of opportunity for change. A crises-response framework was used for examining these dynamics between 1995 and 2009. Crises were defined in relation to their perceived threat, decision time and surprise. Published material was combined with the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLRs) expert interviews, to evaluate changing perceptions of IUU fishing and corresponding actions. A first crisis led to an increased use of informal shortcuts and a concentration of power. A second crisis created windows of opportunities for policy entrepreneurs and stimulated policy innovation. A third crisis led to the implementation of existing contingency plans. These responses were consistent with predictions from the crisis-response framework used. The series of crises threatened the credibility of CCAMLR and changed the incentives for engaging in coalitions, which led to the development of both management and enforcement approaches to compliance. State and non-state actors became increasingly involved in developing these diverse compliance mechanisms, thereby actively contributing to the adaptive capacity of CCAMLR. Synergies between fisheries industry, environmental conservation, and state sovereignty interests were effectively utilized. Individual actors, organizations and countries providing leadership had strong incentives for doing so. Trust and reputation was important for the compliance mechanisms leading to a substantial reduction of IUU fishing.  相似文献   

18.
In this paper we examine ways Sahelian floodplain fishers have adapted to the strong environmental variations that have affected the region in the last two decades. We analyse their vulnerability and adaptive capacity in the face of expected changes in rainfall combined with the predicted effects of dam construction. Data from the Inner Niger Delta in Mali were used to show that fishers were highly sensitive to past and recent variations in the hydro-climatic conditions. Moreover, it appears their traditional livelihood strategies, although diversified, sophisticated and well suited to historical conditions, offer a limited set of options to adapt to increased environmental constraints. For fish-dependent households that have adopted a mixed set of activities through farming, the high seasonality and constraints characterizing both their main activities (fishing and farming) does not allow switching between activities. For those households that undertake seasonal fishing migrations, there is little opportunity to modify migration routes or find new settlements sites inside the delta because of the high population density in this area. In sum, although the adoption of diversified and spatially discrete patterns in livelihood activities is often presented as a strategy to reduce vulnerability, such a strategy does not appear sufficient to allow fishers of the delta to successfully face the increasing constraints associated with the changes in hydro-climatic conditions. In such a context, fishing communities will be driven towards more drastic strategies of adaptation and/or coping such as switching to new activities based on agricultural innovations or emigration from the delta. Both strategies present many hazards, particularly in the absence of supportive public policy.  相似文献   

19.
Bovine spongiform encephalopathy (BSE) has been found in 25 countries, costing billions of dollars in those affected economies, and has had profound social and environmental impacts at multiple scales of organization. As a global phenomenon, the impacts of BSE were mediated directly through the environment (animal and human health) but in Canada the indirect socioeconomic impacts of BSE were far more damaging, especially for farm households. Yet, very little research has been conducted on adaptation to the indirect impacts of global environmental change, such as those mediated through the market and governance. Our goal was to examine how farm households adapted to the Canadian BSE crisis in order to better understand rural adaptations to global zoonotic diseases and to agriculture-related global environmental change as a whole. We conducted our mixed methods research in 2004–2006. Data sources included 826 survey responses, 27 individual interviews and 12 group interviews with farmers and ranchers in western Canada. Factor analysis separated out responses into three general adaptation strategies: ‘innovating’ to pursue new opportunities; ‘enduring’ or adaptations that seek stability; and ‘exiting’ from beef production or agriculture altogether. Farm household and community level innovation was a crucial adaptive strategy in the absence of governmental and expert-based support. Enduring adaptations were important to farm household survival in the short term, yet “chronic enduring” can compromise long-term adaptive capacity. Farm exiting was highly problematic during the BSE crisis as these responses were largely unexpected and often left households more vulnerable. Government support at the farm level promoted stability, with little support provided for change-orientated adaptations. Effective farm adaptation will require support for all three types of adaptive strategies and ones that are both expert-based and grassroots in nature to enable farm households in their pursuit of pluriactive and multifunctional livelihood strategies.  相似文献   

20.
An extraordinary and unprecedented heatwave swept across western North America(i.e., the Pacific Northwest) in late June of 2021, resulting in hundreds of deaths, a massive die-off of sea creatures off the coast, and horrific wildfires. Here,we use observational data to find the atmospheric circulation variabilities of the North Pacific and Arctic-Pacific-Canada patterns that co-occurred with the development and mature phases of the heatwave, as well as the North America pattern,which coincided ...  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号