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1.
本文报道了1995年大连地区扇贝生长,死亡情况的一次大面调查结果,客观地分析了造成扇贝生产过程中死亡率偏高的各种原因,科学地阐述了今后生产管理当中应当注意的几个问题,对水产养殖业的持续发展具有一定的指导意义。  相似文献   

2.
Marine protected areas (MPAs) are increasingly regarded as socio-ecological systems. In addition to their reported ecological effects, MPAs may have important social, economic and cultural effects on local communities and marine and coastal stakeholders. Those effects should be considered within an ecosystem approach to MPA planning, designation and management. Here we present a new framework to monitor and assess the socioeconomic effects of MPAs saliently and soundly: the Integrated MPA Socio-Economic Assessment (IMPASEA). The IMPASEA considers and analyses those factors deemed most important for marine and coastal stakeholders in a spatially referenced, sound and cost-effective manner. The development of the IMPASEA followed a mixed-methods research design in 3 phases: literature review, stakeholder survey and geo-statistical analysis using a Multiple-Paired-Before-After-Control-Impact design (MPBACI). The framework was tested on a set of 6 multiple-use MPAs on the French side of the English Channel. Of the eight socioeconomic variables analysed at the scale of ‘commune’ in the geo-statistical phase, only one variable (‘number of hotel rooms’) might have been affected by the designation of MPAs. Factors such as MPA designation category and management status are likely to have contributed to the non-significant differences shown at the scale of commune for the selected MPAs. In contrast, most of the six variables related to fishing showed differences between ports inside and outside MPAs, although these results need further ground truthing to discriminate attribution of effects. The characteristics of the IMPASEA make it a sound monitoring and assessment framework that could be applied in different contexts and to different types of sustainability assessments involving protected areas or other spatially-defined entities under certain conditions: existence of consistent time series of fine-scale socioeconomic data and avoidance of overlap of designation categories over single spaces.  相似文献   

3.
长海海域浮筏养殖虾夷扇贝生物沉积速率的现场研究   总被引:1,自引:0,他引:1  
为评价浅海高密度、规模化浮筏养殖贝类的生物沉积作用及其环境生态效应,本文运用生物沉积物捕集器对长海海域浮筏养殖虾夷扇贝的生物沉积速率进行了四个季度的现场测定。结果表明,同一养殖区不同排筏虾夷扇贝的生物沉积速率有很大不同,呈现出由低排筏到高排筏逐渐降低的趋势;不同季节虾夷扇贝生物沉积速率变化明显,秋季最高,冬季最低。海水中悬浮颗粒物浓度及水温是影响扇贝生物沉积速率的主要因素。  相似文献   

4.
The designation of marine protected areas (MPAs) may have intense social and economic effects on human communities. Driven by overarching global and European policies and national legislations, current systematic conservation planning in the UK and France requires an ecosystem approach that takes into account not only nature but also the human activities that take place in an area. Here, we identified a set of 64 socioeconomic variables potentially relevant for marine and coastal stakeholders in a European context and a comprehensive set of 20 marine and coastal stakeholder categories. Ninety national organisations in the UK and France belonging to those categories and potentially affected by/interested in the designation of multiple-use MPAs were identified and surveyed. Results show that environmental NGOs, research centres, local councils, managing agencies and statutory nature conservation bodies perceived that they are positively affected by these MPAs, whereas fishers’ organisations, shipping and aggregate industrial organisations and recreational organisations perceived to be chiefly negatively affected by MPAs. On average, the ecological effects of multiple-use MPAs are perceived as ‘largely positive’, though 30% of respondents did not perceive any positive ecological effects from these MPAs. The social, economic and cultural effects of such MPAs are perceived as ‘moderately positive’. Most respondents perceived broad range (>10 km) and permanent ecological, social, economic and cultural effects from multiple-use MPA designation suggesting high societal expectations towards these areas. However, only five variables were perceived to vary in intensity after the designation of multiple-use MPAs: ‘research’, ‘environmental performance by citizens, businesses and towns’, ‘number of green businesses’, ‘tourism’ and ‘economic activities’. The most important ‘social’ variables for stakeholder organisations referred to local populations’ engagement with the MPA, tourism and research. The most important ‘economic’ variables were linked to fishing, shipping and aquaculture activities. These variables highlight relevant topics to be considered in MPA planning, designation and management processes, especially in the UK and France. There were statistically significant differences in the ratings of socioeconomic variables between many organisations belonging to the same intuitive stakeholder categories, suggesting the importance of including as wide a range of stakeholder organisations as feasible in MPA socioeconomic-related processes. Our methods and findings can help to inform and streamline ongoing and future participatory MPA planning, management and monitoring processes in Europe and in other regions with similar socioeconomic characteristics.  相似文献   

5.
This paper examines the risks associated with forest insect outbreaks in a changing climate from biological and forest management perspectives. Two important Canadian insects were considered: western spruce budworm (WSBW; Choristoneura occidentalis Freeman, Lepidoptera: Tortricidae), and spruce bark beetle (SBB; Dendroctonus rufipennis Kirby, Coleoptera: Curculionidae). This paper integrates projections of tree species suitability, pest outbreak risk, and bio-economic modelling.Several methods of estimating pest outbreak risk were investigated. A simple climate envelope method based on empirically derived climate thresholds indicates substantial changes in the distribution of outbreaks in British Columbia for two climate scenarios and both pests. A “proof of concept” bio-economic model, to inform forest management decisions in a changing climate, considers major stand-level harvest decision factors, such as preservation of old-growth forest, and even harvest flow rates in the presence of changing tree species suitability and outbreak risk. The model was applied to data for the Okanagan Timber Supply Area and also the entire Province of British Columbia.At the provincial level, the model determined little net timber production impact, depending on which of two climate scenarios was considered. Several potentially important factors not considered in this first version of the model are discussed, which indicates that impact may be underestimated by this preliminary study. Despite these factors, negative impacts were projected at the Okanagan Timber Supply Area level for both scenarios.Policy implications are described as well as guidance for future work to determine impacts of climate change on future distribution and abundance of forest resources.  相似文献   

6.
以虾夷扇贝(Patinopecten yessoensis)为受试生物,研究了8:2氟调聚羧酸(8:2FTCA)在虾夷扇贝不同组织(肝脏、鳃、性腺、外套膜、闭壳肌)中的蓄积、分布和生物转化特征.结果显示,8:2FTCA蓄积浓度最高的组织为肝脏,达峰值最快的组织为鳃.在8:2FTCA代谢过程中,检测到8:2氟调聚不饱和酸(8:2FTUCA)、7:3氟调聚羧酸(7:3FTCA)、全氟辛酸(PFOA)、全氟壬酸(PFNA)和全氟庚酸(PFHpA)5种代谢产物,其中7:3FTCA和PFOA为含量最丰富的2种代谢产物.它们主要分布在鳃和肝脏组织中,鳃和肝脏是8:2FTCA进行生物转化的主要器官,并且鳃组织中代谢产物的浓度最高.推测出虾夷扇贝体内8:2FTCA的生物转化路径,与虹鳟的生物转化行为相比,虾夷扇贝在代谢产物产量和半衰期上均有差异,说明水生生物的生物转化行为具有物种差异性.8:2FTCA在虾夷扇贝体内可转化为PFOA、PFNA和PFHpA等全氟烷基羧酸(PFCAs),是虾夷扇贝体内PFCAs的一个间接来源.  相似文献   

7.
以虾夷扇贝(Patinopecten yessoensis)为受试生物,研究了8:2氟调聚羧酸(8:2FTCA)在虾夷扇贝不同组织(肝脏、鳃、性腺、外套膜、闭壳肌)中的蓄积、分布和生物转化特征.结果显示,8:2FTCA蓄积浓度最高的组织为肝脏,达峰值最快的组织为鳃.在8:2FTCA代谢过程中,检测到8:2氟调聚不饱和酸(8:2FTUCA)、7:3氟调聚羧酸(7:3FTCA)、全氟辛酸(PFOA)、全氟壬酸(PFNA)和全氟庚酸(PFHpA)5种代谢产物,其中7:3FTCA和PFOA为含量最丰富的2种代谢产物.它们主要分布在鳃和肝脏组织中,鳃和肝脏是8:2FTCA进行生物转化的主要器官,并且鳃组织中代谢产物的浓度最高.推测出虾夷扇贝体内8:2FTCA的生物转化路径,与虹鳟的生物转化行为相比,虾夷扇贝在代谢产物产量和半衰期上均有差异,说明水生生物的生物转化行为具有物种差异性.8:2FTCA在虾夷扇贝体内可转化为PFOA、PFNA和PFHpA等全氟烷基羧酸(PFCAs),是虾夷扇贝体内PFCAs的一个间接来源.  相似文献   

8.
The irrigation sector constitutes the backbone of Uzbekistan's economy, providing social and economic stability in the region. The sector collapsed with the fall of the Soviet Union, due to worsening of infrastructure conditions causing tensions among resource users. Subsequent irrigation management reforms were implemented in a top-down manner. More than a decade after the initial reforms – which established local Water Consumers Association (WCA) and transferred operation and maintenance responsibilities for on-farm irrigation canals – the poor performance of these associations is still apparent, illustrating the heritage of the strong role of state agencies in Uzbek water management that still affects collective irrigation management today. This paper identifies the necessary and sufficient conditions for successfully managing common pool resources (CPRs) and, more specifically, irrigation canal maintenance in the rural Bukhara region of Uzbekistan. Fifteen WCAs were examined regarding conditions that may facilitate successful irrigation canal maintenance. Methods involved focus group discussions and in-depth interviews with the associations concerned. Data gathered was analyzed using fuzzy-set qualitative comparative analysis. The results indicate that two paths of local factors can lead to well-maintained irrigation canals: (1) the combination of appropriate chairmanship skills with sustainable resource appropriation or (2) the combination of appropriate chairmanship skills with the presence of effective participatory governance. The results also illustrate the role of path-dependence and traditional co-production of irrigation management in Uzbekistan.  相似文献   

9.
Water sector reforms based on the concept of Integrated Water Resources Management (IWRM) are criticized for not considering context, local realities or legitimacy during the implementation of water sector reforms. Universal remedies of IWRM can thus lead to resistance, conflicts and ultimately failures of interventions. This paper examines how conflicts and disharmony can be addressed by IWRM's instruments. It conceptualizes institutional security as a highly relevant issue to be addressed during water management interventions. Further, the paper advocates a reform of the holistic concept of IWRM to incorporate ‘peace and security’ as a new pillar of water management based on a broad understanding of societal goals that are embedded in the principles of good governance and sustainable development. It also reviews recent criticism of and debates in IWRM and explains the advantages of expanding the normative idea behind it.  相似文献   

10.
渔业配额制度的起源、特点及展望   总被引:2,自引:0,他引:2  
白洋 《自然资源学报》2012,27(3):522-528
渔业配额制度是在渔业资源过度捕捞所导致的渔业危机和传统的投入控制管理失效的历史背景下,基于渔业资源生态特性而构建的一种产出控制的渔业管理模式。它是在总可捕量基础上发展起来的,并在冰岛、 新西兰等国家得以成功实施。该制度具有专属性、 可转让性、 激励性等外在法律特征。学者对于配额制度的法律特性持不同观点,认同其准物权的特性是主流观点。资源的生物特性以及制度的实质内涵告诉我们,无论是国际配额还是国内配额,制度要想取得实效,必须牢牢遵循不得超越总可捕量的共同义务这一要旨,通过落实有限准入、 加强监管等多种手段来保障这种共同义务的履行,才能实现资源的永续利用。  相似文献   

11.
Since the late 1970s the central government of China has initiated several ecological environmental protection projects. The most significant of these has been the tui geng huan lin (returning cultivated land to forest and pasture) project in operation since the late 1990s. China's northwest region is characterized by lack of water resources, yet such resources are of vital importance. There is scant discussion in the literature (including in China) on the linkages between the environmental protection projects and water management practices. This paper analyses how central government environmental protection projects are interpreted in the local setting, and how local water management policies and practices correspond to the projects. The conclusion is that local water management policies and practices are interlinked with both central government and local government policies on the environmental protection projects, and a new process for the redistribution of water has been established. When equity and social costs are not factored into the planning of new environmental protection projects, the social costs may be as high as the environmental costs.  相似文献   

12.
饮用水中甲羟孕酮的臭氧氧化降解研究   总被引:2,自引:2,他引:0  
以饮用水中内分泌干扰物孕激素类甲羟孕酮(MPA)为目标物,采用臭氧氧化工艺对其进行降解,对臭氧降解过程动力学进行了研究,并考察液相臭氧浓度、pH、羟基自由基(.OH)清除剂(HCO3-)对降解过程的影响.结果表明,臭氧在合适条件下能够有效降解水溶液中的MPA,MPA初始浓度为3、5、10 mg.L-1,采用连续臭氧曝气方式降解时,降解过程遵守一级反应动力学模型;采用序批式臭氧投加方式进行降解时,降解过程符合二级反应动力学模型.pH的升高和HCO3-的添加都会对降解效果产生负面影响.在反应温度为20℃,采用序批式臭氧投加方式,MPA的去除率从pH=3.10时的89.8%下降到pH=9.02时的74.6%.相同反应条件下,添加羟基自由基清除剂HCO3-后,降解反应速率常数由0.146 3 L.(mg.min)-1下降到0.049 5 L.(mg.min)-1,去除率下降了22.2个百分点.  相似文献   

13.
Sustainable mangrove management needs to consider trade-offs between multiple benefits provided by mangrove ecosystems and to balance the conflicting objectives of various stakeholders. The aim of the present study is to assess the sustainability of mangrove management based on the life cycle approach. We examine two mangrove management systems in Thailand, namely, the strict preservation and charcoal production systems. The results show that the strict preservation system has an advantage over the charcoal production system from the environmental perspective (the net amount of CO2 absorbed by mangroves) while the charcoal production is a more favorable system than strict preservation from the social perspective (the amount of employment created in local communities). On the other hand, it is difficult to say that both systems are sustainable from an economic aspect. The charcoal production system needs to develop improved management regimes for commercial charcoal production and requires financial assistance in the period when its net cash flows are negative. As solutions for these problems, the introduction of community forest management and the utilization of a fund for REDD (Reducing Emissions from Deforestation and Degradation in Developing Countries) can be proposed.  相似文献   

14.
In West Africa, rural livelihoods depending on natural resources develop coping and adapting strategies to face climate variability or change and economic or political changes. The former Lake Faguibine in northern Mali has experienced drastic ecological, social, and economic changes. Forests have emerged on the former lake and have become important for local livelihoods. This paper analyses the coping and adapting strategies of forest- and livestock-based livelihoods facing ecological changes. Results from field research at different levels indicate that most local strategies are based on diversification including migration within the livestock production system or in complement to it, with differences according to gender, age, and ethnicity. Political discourses, cultural identities, and past experiences influence and shape adaptation strategies at the local level. The sustainability of the observed strategies depends on the access to natural resources and the sustainable management of these resources, which in turn depends on institutions at local and national levels. Many local strategies are reactive to external events but would need strategic support from higher levels to move from coping to adapting. Examples are the development of institutions and technical actions for natural resource management, as well as development actions supporting local strategies and sustainable investments. Researchers, practitioners and development planners will need simple methods and tools for understanding and analysing local adaptation perceptions and actions to achieve an effective support of sustainable and gender-equitable local adaptation and to avoid mismatches between strategies proposed by local and by sub national and national actors.  相似文献   

15.
Inter-organizational collaboration in networks and partnerships is supposed to promote the potential for learning and innovation needed for environmental transformation and sustainable development. This paper aims at exploring the roles of local authorities (LAs) in actor-networks related to regional sustainable development, and examining their potential in stimulating learning and innovation related to sustainable development. From empirical case studies it is suggested that LAs can act as ‘teachers’ or ‘tutors’ in the networks. From further analysis, drawing also from literature on partnerships, innovation management, socio-technical change, and educational science, it is proposed that in the short run both the ‘teacher’ and ‘tutor’ approach would promote incremental innovation rather than the radical system innovations needed for sustainable development. However, there is potential for stimulating more long-term, radical change if the LA takes on the role of a ‘teacher’. This approach may favour close collaboration in long-lived, multi-actor networks with potential to (i) serve as forum for continuous dialogue on sustainable development at a community level, (ii) stimulate experimentation and learning needed for system innovations, and (iii) provide a basis for strategic niche management for development and testing of new technologies.  相似文献   

16.
Small farmers who supply the city of Bogotá with food are facing many challenges that are jeopardizing their livelihoods and by extension, the food security of Colombia’s capital. We expect future changes in climatic conditions to exacerbate the plight of the small farmers and this is expected to compromise Bogota’s food security even further. This paper specifically seeks to assess the impact of climate change (CC) on the livelihoods of smallholders who supply Bogota with most of its food. In our multidisciplinary methodology, we translated the exposure to CC into direct impact on crops and assessed sensitivity and adaptive capacity using the sustainable rural livelihoods framework. The results show that rainfall (by average of 100 mm) and temperature (by average of 2.1 °C) will increase over the study area, while the future climate suitability of the most important crops such as mango (Mangifera indica), papaya (Carica papaya), corn (Zea mays) and plantain (Musa balbisiana) shows a decrease of 19 % to 47 % climate suitability by the year 2050. The assessment of sensitivity and adaptive capacity demonstrates that farmers participating in a farmers’ market, initiated by several local and international non-governmental organizations (NGOs), are less vulnerable to CC than farmers who sell through intermediaries. Those farmers selling directly to consumers in the farmers’ market have a higher adaptive capacity (3 on a scale of 3) in social and financial capital than those selling to intermediaries with less adaptive capacity (1 on a scale of 3). In light of the reduction in overall climatic suitability of some of the major crops and the change of geographic location of suitability for others, there are likely to be serious threats for Bogotá’s food security, the ecological landscape around the city, and farmers’ livelihoods. We further conclude that unless proper adaptation measures are implemented, the geographical shift in climate suitability may also force farmers to shift their crops to higher elevations including remaining forests and páramos (the Colombian alpine tundra ecosystems), which may be threatened in the near future.  相似文献   

17.
选取海洋双壳贝类栉孔扇贝为目标生物,研究不同质量浓度(0 mg/L、0.2 mg/L、1 mg/L、5 mg/L、25 mg/L)的洛克沙胂暴露条件下,砷(As)在栉孔扇贝4种组织(肝胰腺、鳃、闭壳肌、外套膜)中的富集和释放规律。结果表明:(1)自然海域和在清洁海水中,栉孔扇贝4种组织中As含量排序均为鳃>肝胰腺>外套膜>闭壳肌。(2)富集过程中,As的组织含量排序为肝胰腺>鳃>外套膜>肌肉,释放过程中,As的组织平均释放率排序为鳃>肝胰腺>外套膜>闭壳肌。(3)洛克沙胂进入扇贝体内的主要途径为鳃的摄食和滤水作用,As在扇贝体内的主要富集靶点为肝胰腺、鳃和外套膜。(4)在本实验中,富集过程,As在扇贝体内的富集-转移/释放的平均周期为22 d;富集/释放过程,As在扇贝体内的富集-转移/释放的平均周期为15 d,共循环2个周期,然后扇贝As含量趋于稳定。  相似文献   

18.
Oysters contaminated with norovirus present a significant public health risk when consumed raw. In this study, norovirus genome copy concentrations were determined in Pacific oysters (Magallana gigas) harvested from a sewage-impacted production site and then subjected to site-specific management procedures. These procedures consisted of relocation of oysters to an alternative production area during the norovirus high-risk winter periods (November to March) followed by an extended depuration (self-purification) under controlled temperature conditions. Significant differences in norovirus RNA concentrations were demonstrated at each point in the management process. Thirty-one percent of oyster samples from the main harvest area (Site 1) contained norovirus concentrations >?500 genome copies/g and 29% contained norovirus concentrations <?100 genome copies/g. By contrast, no oyster sample from the alternative harvest area (Site 2) or following depuration contained norovirus concentrations >?500 genome copies/g. In addition, 60 and 88% of oysters samples contained norovirus concentrations <?100 genome copies/g in oysters sampled from Site 2 and following depuration, respectively. These data demonstrate that site-specific management processes, supported by norovirus monitoring, can be an effective strategy to reduce, but not eliminate, consumer exposure to norovirus genome copies.  相似文献   

19.
Recent interest in sustainable forest management planning in the Yukon has coincided with growing public awareness of climate change, providing an opportunity to explore how forestry plans are incorporating climate change. In this paper, the Strategic Forest Management Plans for the Champagne and Aishihik First Nations Traditional Territory (CATT) and the Teslin Tlingit Traditional Territory (TTTT) are examined for evidence of adaptation to climate change. For each plan, management policies and practices that are also recognized as ways to adapt to climate change are identified to provide information on the incremental costs and benefits of additional adaptation efforts. A typology for classifying sustainable forest management plans according to how they address climate change is proposed and applied to the CATT and TTTT plans. This typology, which may be useful to any future retrospective assessments on how successful these or other sustainable forest management plans have been in addressing and managing the risks posed by climate change, consists of a matrix that categorizes plans into one of four types; (1) proactive-direct, (2) proactive-indirect, (3) reactive-direct, and (4) reactive-indirect. Neither of the plans available for the southern Yukon explicitly identifies climate change vulnerabilities and actions that will be taken to reduce those vulnerabilities and manage risks. However, both plans have incorporated some examples of ‘best management practices’ for sustainable forest management that are also consistent with appropriate climate adaptation responses. Even in a jurisdiction facing rapid ecological changes driven by climate change, where there is a relatively high level of awareness of climate change and its implications, forestry planning processes have yet to grapple directly with the risks that climate change may pose to the ability of forest managers to achieve the stated goals and objectives of sustainable forest management plans.
J. L. InnesEmail:
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20.
Nearly 50 years after Hardin’s “tragedy of the commons” we have not yet found predictive tools to guide us towards sustainable management of common-pool resources (CPR). We often have a good understanding of the qualitative relationships between the principal actors in socioecological systems (SESs), but classical quantitative approaches require a tremendous amount of data to understand the drivers of SESs sustainability. Here we show that qualitative modelling approaches can provide important governance insights for SESs that are understood but not quantified.We used Loop Analysis to test the outcomes of different management regimes on a simple nature-based tourism SES described by economic, social and environmental variables. We tested the sustainability of different management scenarios on this system and we identified the necessary conditions to achieve it.We found that management regimes where property rights and responsibilities are shared between different stakeholders are more likely to be successful. However, the system is generally highly unstable and it is important to tune each strategy to each particular situation.The conditions for sustainability found across the different systems tested were: a low reinvestment rate of tourist revenues into new infrastructures and a low growth rate of the environment. Management strategies based on maximum sustainable yield, which keep the environment far from its carrying capacity, have less chance to be sustainable.Qualitative models of SESs are powerful diagnostic tools; they can help identifying variables that play an important role in determining socioecological sustainability in data-poor circumstances and guide the design of efficient data collection programmes. Our results highlight the importance of careful planning when designing management strategies for nature-based tourism. The application of one-size-fits-all solutions to every situation is likely to lead to the failure of the commons; however tourism-based SESs can be sustainable if management strategies are tuned to each particular case.  相似文献   

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