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1.
The very large changes observed within marine communities, owing to excessive harvesting, have been attributed to switches between alternative stable states. Correspondingly large reductions in overall fishing effort are usually difficult to implement. For such 'nonlinear' ecosystems, introducing large marine protected areas, with low to zero harvesting, but without reduction in overall fishing effort, can give a marked increase in total yield of the depleted stocks. These increases, however, are still less than can be achieved by reducing fishing effort.  相似文献   

2.
The ability of marine protected areas (MPAs) to provide protection from indirect stressors, via increased resilience afforded by decreased impact from direct stressors, remains an important and unresolved question about the role MPAs can play in broader conservation and resource management goals. Over a five-year period, we evaluated coral and fish community responses inside and outside three MPAs within the Roviana Lagoon system in Solomon Islands, where sedimentation pressure from upland logging is substantial. We found little evidence that MPAs decrease impact or improve conditions and instead found some potential declines in fish abundance. We also documented modest to high levels of poaching during this period. Where compliance with management is poor, and indirect stressors play a dominant role in determining ecosystem condition, as appears to be the case in Roviana Lagoon, MPAs may provide little management benefit.  相似文献   

3.
A method is described for rapid multidisciplinary environmental assessment of coastal areas within the conceptual framework of comprehensive management of Marine Protected Areas (MPAs). The aim is to provide tools for the selection, design and management of coastal MPAs when time, budget or potential human pressures, either alone or in combination, create an urgent need for prioritisation. Maximising results and minimising cost and time is the goal, using a methodology that re evaluates existing information on the area, allows use of physical, environmental and socio-economic indicators, and finally integrates information in a Geographic Information System capable of generating outputs in the form of thematic maps to support managers.The final products obtained inform planners and managers about the study areas, across multiple aspects that all need to be considered in integrated coastal management. Although originally proposed for widespread use in the Mediterranean, this methodology can be flexibly adapted, with minor modifications in the selection of indicators, for its use in other regions. The results show its potential for merging and synthesising information not only as a tool in Rapid Assessment Programs but also as a tool for facing management of wide coastal areas as social-ecological ecosystems.  相似文献   

4.
Recently there has been increased interest in the use of Marine Protected Areas (MPAs) as tools for the conservation of marine habitats and species. This has resulted in the declaration of many MPAs around the world. Despite this activity there have been few tests of hypotheses about the design criteria for selection and management of these areas, resulting in a haphazard and ad hoc selection of protected areas, with conflicting and inconsistent terminology and objectives. The application of appropriately tested scientific information to the design of MPAs will increase the likelihood of success in the future.To 1st January 1992, 267 MPAs had been declared in Australia, covering a total area of ca 400 019 km2. The history of their declaration has been sporadic and uneven. Conflicts over State and Federal legislation and, within states, conflicts over jurisdiction among agencies caused by overlapping responsibilities, have at times slowed the declaration of MPAs. In this paper, the history of MPAs in Australia is used as a case study to discuss the problems, both biological and administrative, of declaring MPAs.  相似文献   

5.
This paper is about modeling the perceived social impacts of three proposed marine protected areas (MPAs), each designed to protect coral reefs. The paper argues that shared perceptions of these impacts have resulted in different community-level responses to these MPA proposals. The study is uniquely situated in the Bahamas where the government has approved setting aside 30 No-take MPAs (including three under study here) to protect the coastal marine environment. The paper is based on 572 interviews conducted during eight field trips with members of six traditional settlements in the Exuma Islands and Cays in the central Bahamas. Overall, 34% of the census population of these settlements was interviewed at least once. Key findings are that an MPA can impact in either positive or negative ways (a) community agency by the process of siting, (b) community resilience by eliminating or supporting some components of their traditional adaptations to social and natural environments, and (c) community identity by precluding or protecting customary marine access. MPA impacts to local communities determine whether those communities will support or resist proposed MPAs.  相似文献   

6.
保护区的分类系统与标准   总被引:5,自引:1,他引:5  
保护区是一个泛称,根据建立的目的和本身的特点可以划分不同的类型,以利于管理工作的开展。每一个国家都应制订一个与本国资源和要求相适应的保护区分类系统。本文着重讨论按保护对象和保护区性质划分的保护区类型,以供判断每一个保护区的归属和管理重点。  相似文献   

7.
Models provide useful insights into conservation and resource management issues and solutions. Their use to date has highlighted conditions under which no-take marine protected areas (MPAs) may help us to achieve the goals of ecosystem-based management by reducing pressures, and where they might fail to achieve desired goals. For example, static reserve designs are unlikely to achieve desired objectives when applied to mobile species or when compromised by climate-related ecosystem restructuring and range shifts. Modelling tools allow planners to explore a range of options, such as basing MPAs on the presence of dynamic oceanic features, and to evaluate the potential future impacts of alternative interventions compared with ‘no-action’ counterfactuals, under a range of environmental and development scenarios. The modelling environment allows the analyst to test if indicators and management strategies are robust to uncertainties in how the ecosystem (and the broader human–ecosystem combination) operates, including the direct and indirect ecological effects of protection. Moreover, modelling results can be presented at multiple spatial and temporal scales, and relative to ecological, economic and social objectives. This helps to reveal potential ‘surprises'', such as regime shifts, trophic cascades and bottlenecks in human responses. Using illustrative examples, this paper briefly covers the history of the use of simulation models for evaluating MPA options, and discusses their utility and limitations for informing protected area management in the marine realm.  相似文献   

8.
Quasi-experimental impact evaluation approaches, which enable scholars to disentangle effects of conservation interventions from broader changes in the environment, are gaining momentum in the conservation sector. However, rigorous impact evaluation using statistical matching techniques to estimate the counterfactual have yet to be applied to marine protected areas (MPAs). While there are numerous studies investigating ‘impacts’ of MPAs that have generated considerable insights, results are variable. This variation has been linked to the biophysical and social context in which they are established, as well as attributes of management and governance. To inform decisions about MPA placement, design and implementation, we need to expand our understanding of conditions under which MPAs are likely to lead to positive outcomes by embracing advances in impact evaluation methodologies. Here, we describe the integration of impact evaluation within an MPA network monitoring programme in the Bird''s Head Seascape, Indonesia. Specifically we (i) highlight the challenges of implementation ‘on the ground’ and in marine ecosystems and (ii) describe the transformation of an existing monitoring programme into a design appropriate for impact evaluation. This study offers one potential model for mainstreaming impact evaluation in the conservation sector.  相似文献   

9.
Kareiva P 《Current biology : CB》2006,16(14):R533-R535
Socioeconomic and ecological analyses of eleven coral reef conservation efforts make clear that marine protected areas are not the answer, and that in fact support of local communities is far more important than some government mandated 'fishing closure'. Apparently there are marine 'paper parks' just as there are terrestrial 'paper parks'.  相似文献   

10.
The Habitats Directive celebrates its 20th anniversary in 2012. The influence of the Directive now extends across 27 Member States, compared to just 12 when it was first adopted in May 1992. The sites now cover more than 17% of the land surface of the Member States. However, in spite of their deep roots in human history, reviewed here, and their long-time justification on the basis of intrinsic value, protected areas must face the economic challenges of the modern era. There is a need for policy that can guide decision-making in relation to their continued designation, protection and management, including the ecosystem services that they deliver and taking into account the needs of the local communities who live and work in and around them. Growing pressures include their potential exploitation for economic and commercial benefit and the continued threats from competition over land use and climate change.  相似文献   

11.
In an increasingly human-dominated world, more realistic, holistic and durable linkages need to be created for protected areas (PAs), for the sake of long-term conservation of species and habitats, and of ecosystem goods and services for serving the local people, as well as societies at large. In conjunction, geographical, physical and biological concepts of linkages need to be extended to embrace socio-economic factors. This paper develops a conceptual approach to this task, employing the nascent notions of ‘emerging ecosystems’, restoring natural capital and ‘socio-ecological systems’. We employ the value notion generally used by economic science, i.e. monetary value, as a conceptual tool in the unavoidable assessment process that modern societies must undertake to decide about conserving or restoring PAs, and ecosystems in general. We also draw attention to the importance of ecological and socio-economic thresholds of irreversibility in the evaluation and decision-making process concerning PAs and their linkages with other PAs, and especially with the unprotected world beyond their boundaries.  相似文献   

12.
Designing marine protected areas for migrating fish stocks   总被引:1,自引:0,他引:1  
This paper extends an earlier analysis and presents an investigation of how migration rates affect the performance of various types of management regimes with respect to economic yield and conservation benefits. Particular emphasis is placed on evaluating the geometric design of marine protected areas (MPAs). Earlier results have shown that MPAs are only likely to provide significant benefits when they are used in conjunction with direct catch or effort controls, unless they are quite large and cover most of the resource in question. Conversely, catch and effort controls are far more effective when protected areas are included in the management regime as a buffer against uncertainty. Dispersal of reproduction (recruitment) to other areas is an important expected benefit of protected areas, but such dispersal increases the variability of the effects of the area protection. If fishing mortality rates outside of the protected area are not controlled then dispersal can result in nullifying some of the benefits of the protected area. Similarly, adult migration increases the variability in the results when an area is protected and critically depends upon an overall control of fishing mortality outside the area. For both dispersal and migration separately or in combination, however, there are clear benefits to using MPAs in conjunction with catch or effort controls. These benefits are expressed in terms of long-term yield and recovery probabilities. In addition, short-term yield declines relatively slowly with increasing area protected. Design of the protected areas is seen to be important since using contiguous areas provide greater protection against overfishing than protected areas in isolation.  相似文献   

13.
14.
15.
Marine protected areas (MPAs) are promoted as a tool to protect overfished stocks and increase fishery yields. Previous models suggested that adult mobility modified effects of MPAs by reducing densities of fish inside reserves, but increasing yields (i.e., increasing densities outside of MPAs). Empirical studies contradicted this prediction: as mobility increased, the relative density of fishes inside MPAs (relative to outside) increased or stayed constant. We hypothesized that this disparity between theoretical and empirical results was the result of differential movement of fish inside versus outside the MPA. We, therefore, developed a model with unequal and discontinuous diffusion, and analyzed its steady state and stability. We determined the abundance in the fishing grounds, the yield, the total abundance and the log ratio at steady-state and examined their response to adult mobility (while keeping the relative inequity in the diffusion constant). Abundance in the fishing grounds and yield increased, while total abundance and log-ratio decreased, as mobility increased. These results were all qualitatively consistent with the previous models assuming uniform diffusivity. Thus, the mismatch between empirical and theoretical results must result from other processes or other forms of differential movement. Therefore, we modified our original model by assuming that species located on the boundary of the MPA will preferentially move towards the MPA. This localized movement bias model gives rise to steady state profiles that can differ radically from the profiles in the unbiased model, especially when the bias is large. Moreover, for sufficiently large bias values, the monotonicity of the four measures with increased mobility is reversed, when compared with our original model. Thus, the movement bias model reconciles empirical data and theoretical results.  相似文献   

16.
Reviews in Fish Biology and Fisheries - There has been a dramatic increase in recentyears in the number of papers, reports, etc.,which have been published concerning MarineProtected Areas (MPAs)....  相似文献   

17.
There has been a dramatic increase in recentyears in the number of papers, reports, etc.,which have been published concerning MarineProtected Areas (MPAs). This overview of theobjectives, selection, design and management ofMPAs aims to provide a basis for discussionregarding possible ways forward by identifyingemerging issues, convergences and divergences. Whilst the attributes of the marine environmentmay limit the effectiveness of site-specificinitiatives such as MPAs, it is argued that itwould be defeatist in the extreme to abandonMPAs in the face of these limitations. Ten keyobjectives for MPAs are discussed, includingthat of harvest refugia, and it is argued thatwhilst these objectives may be justifiable froma preservationist perspective, they may beobjected to from a resource exploitationperspective. MPAs generate both internal(between uses) and basic (between use andconservation) conflicts, and it is argued thatthese conflicts may be exacerbated whenscientific arguments for MPAs are motivated bypreservationist concerns. It is reported thata minority of MPAs are achieving theirmanagement objectives, and that for themajority insufficient information was availablefor such effectiveness evaluations. Structureand process-oriented perspectives on marineconservation are discussed. It is argued thatthere are two divergent stances concerningoptimal MPA management approaches: top-down,characterized as being government-led andscience-based, with a greater emphasis onset-aside; and bottom-up, characterized asbeing community-based and science-guided, witha greater emphasis on multiple-use. Given thedivergent values of different stakeholders, thehigh degree of scientific uncertainty, and thehigh marine resource management decisionstakes, it is concluded that a key challenge isto adopt a ``middle-ground' approach whichcombines top-down and bottom-up approaches, andwhich is consistent with the post-normalscientific approach.  相似文献   

18.
In México, 63% of the mammalian carnivore species are considered threatened. Therefore, we performed a prioritization exercise to find sets of areas needed for the conservation of Mexican terrestrial carnivores. Using a grid of half-degree cells, we mapped the distribution of richness, endemic and threaten species. Then, we determine the efficiency of the natural protected areas in México for protecting carnivores. Finally, we define optimal sets of complementary cells needed to represent all species either one or five times, or to represent at least 10% of the geographic distribution range of each carnivore in México. We perform this analysis including or excluding the existing protected areas, or excluding the top 10% cells with highest human population density (HPD). Species richness was higher in south-eastern México, threatened species concentrate in the same region, and also in the Yucatan's Peninsula. The Baja California Peninsula and the central region of the Mexican Plateau is where lower richness and numbers of threatened species are found. There is only one endemic carnivore distributed in the central and southern portion of the Pacific Slope. Complementary analysis showed that sets of three, 16 and 71 cells are required to represent one time, five times or at least 10% of the total distribution range of all species. Sets of 35 cells are needed to complement the natural protected areas to achieve this last representation goal. Finally, if cells with highest HPD are excluded, sets of three, 14 and 71 cells are needed to achieve our three representation goals. Our results provide insight into the ability of different sites to contribute to the representation of carnivore diversity at the national scale, and indicate gaps in the existing protected area network.  相似文献   

19.
Protected areas are key to conservation of biodiversity, and Australia is one of the world’s megadiverse regions. Monitoring programs provide the information to assess the state of conservation resources, the severity of threats and the success of management responses. Here we compare the management priorities, monitoring priorities and actual monitoring practices of protected area management agencies in Australia, using four sets of data at continental scale and five at a more restricted regional scale. We track changes over a period of several years and focus at successively finer levels of detail. At both continental and regional scales, most management plans emphasise fire, invasive species and visitor management; and most monitoring programmes refer to visitor numbers and impacts as well as species and ecosystems. There is only a weak match, however, between reported management priorities and actual monitoring programmes; and the effectiveness of management responses is rarely monitored. The level of detail in visitor monitor programmes varies considerably: most parks count visitors, but few know what those visitors do. Threats from fire and invasive species receive more attention that those from recreation. At regional scale, the proportion of parks with defined monitoring programmes and priorities increased significantly from 2003/2004 to 2006/2007. Whilst only a proportion of protected areas monitor endangered species populations, for those that do this is the parameter reported in most detail, with many parks reporting single records of single individuals. Some parks also maintain anecdotal records of rare species outside routine monitoring programs.  相似文献   

20.
Protected areas (PAs) play an important role in biodiversity conservation and the implementation of ambitious multilateral environmental agreements, like the 2010 targets of the Convention on Biological Diversity (CBD). In the CBD's Programme of Work on Protected Areas, it is requested that each country conduct management effectiveness evaluations of at least thirty percent of its PAs by 2010. This article compares the most common methodologies of PA management effectiveness evaluations, such as the Rapid Assessment and Prioritization of Protected Area Management (RAPPAM) Methodology, the Management Effectiveness Tracking Tool (METT) and UNESCO's Enhancing our Heritage (EoH) Toolkit. These and other methodologies can help to (1) examine overall effectiveness of PAs, (2) identify factors influencing the effectiveness and (3) determine common threats and their seriousness.However, the outcomes of major studies concerning overall effectiveness as well as success and failure factors for PA management are partially contradictory. Different results can be due to the approach (e.g. number and type of indicators or assessors included in the evaluation process) or to the individual context of the PA (e.g. age, region, IUCN category) and therefore these factors need to be considered when comparing results of management effectiveness studies.Research indicates that increased attention should be paid to regular monitoring of conservation activities in PAs including systematic social science studies with a socio-economic and socio-cultural focus. Unfortunately, the outcomes of the management effectiveness studies are not easily accessible and have not yet been widely shared or distributed among the conservation community.
  相似文献   

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