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1.

Co-management, a governance process whereby management responsibility is shared between resource users and other collaborators, is a mainstream approach for governing social and ecological aspects of small-scale fisheries. While many assessments of co-management are available for single time periods, assessments across longer time-scales are rare–meaning the dynamic nature, and long-term outcomes, of co-management are insufficiently understood. In this study we analyse ten-years of catch and effort data from a co-managed, multi-species reef fishery in Solomon Islands. To further understand social, ecological and management dynamics we also draw on interviews with fishers and managers that had been conducted throughout the same decade. We aimed to answer (1) what are the temporal trends in fishing effort, harvesting efficiency, and catch composition within and beyond a periodically-harvested closure (i.e. a principal and preferred management tool in Pacific island reef fisheries), and, (2) what are the internal and external drivers that acted upon the fishery, and its management. Despite high fishing effort within the periodically-harvested closure, catch per unit effort remained stable throughout the ten years. Yet the taxonomic composition of catch changed substantially as species targeted early in the decade became locally depleted. These observations indicate that both the frequency of harvesting and the volumes harvested may have outpaced the turnover rates of target species. We argue that this reflects a form of hyperstability whereby declining abundance is not apparent through catch per unit effort since it is masked by a shift to alternate species. While the community sustained and adapted their management arrangements over the decade as a response to internal pressures and some signs of resource changes, some external social and ecological drivers were beyond their capabilities to govern. We argue the collaborative, knowledge exchange, and learning aspects of adaptive co-management may need even more attention to deal with this complexity, particularly as local and distal pressures on multi-species fisheries and community governance intensify.

Graphical abstract
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Acceptance of marine protected areas (MPAs) as fishery and conservation tools has been hampered by lack of direct evidence that MPAs successfully seed unprotected areas with larvae of targeted species. For the first time, we present direct evidence of large-scale population connectivity within an existing and effective network of MPAs. A new parentage analysis identified four parent-offspring pairs from a large, exploited population of the coral-reef fish Zebrasoma flavescens in Hawai'i, revealing larval dispersal distances ranging from 15 to 184 km. In two cases, successful dispersal was from an MPA to unprotected sites. Given high adult abundances, the documentation of any parent-offspring pairs demonstrates that ecologically-relevant larval connectivity between reefs is substantial. All offspring settled at sites to the north of where they were spawned. Satellite altimetry and oceanographic models from relevant time periods indicated a cyclonic eddy that created prevailing northward currents between sites where parents and offspring were found. These findings empirically demonstrate the effectiveness of MPAs as useful conservation and management tools and further highlight the importance of coupling oceanographic, genetic, and ecological data to predict, validate and quantify larval connectivity among marine populations.  相似文献   

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Successful protected area networks must represent biodiversity across taxonomic groups. However, too often plant species are overlooked in conservation planning, and the resulting protected areas may, as a result, fail to encompass the most important sites for plant diversity. The Mozambique Tropical Important Plant Areas project sought to promote the conservation of Mozambique's flora through the identification of Important Plant Areas (IPAs). Here, we use the Weighted Endemism including Global Endangerment (WEGE) index to identify the richest areas for rare and endemic plants in Mozambique and subsequently evaluate how well represented these hotspots are within the current protected area and IPA networks. We also examine the congruence between IPA and protected areas to identify opportunities for strengthening the conservation of plants in Mozambique. We found that high WEGE scores, representing areas rich in endemic/near-endemic and threatened species, predict the presence of IPAs in Mozambique, but do not predict the presence of protected areas. We also find that there is limited overlap between IPAs and protected areas in Mozambique. We demonstrate how IPAs could be an important tool for ensuring priority sites for plant diversity are included within protected area network expansions, particularly following the adoption of the “30 by 30” target agreed within the post-2020 Convention on Biological Diversity framework, with great potential for this method to be replicated elsewhere in the global tropics.  相似文献   

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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   

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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   

6.
Most studies examining effects of marine protected areas (MPAs) on fish assemblages are potentially confounded, either because they are once off comparisons between fished and unfished locations, or because they are snapshot studies over a fixed period. Here we compare long-term changes within fully protected Tasmanian marine reserves with changes at external reference sites on an annual basis over the first ten years of protection. The results highlight the importance of long-term datasets for differentiating changes occurring over differing time scales. Notable results include a statistically significant increase in abundance of Latridopsis forsteri and large fish (> 300 mm) when examined across all reserves relative to controls, and a 10-fold increase in the abundance of large fish and a doubling of per site species richness of large fish within the Tinderbox Marine Reserve relative to controls. Short-term resident species that recruit sporadically show very different patterns in reserves compared to those that recruit regularly and have long-term age-class storage. While several recent reviews have suggested size of MPAs and duration of protection has little influence on the extent of recovery, our results suggest this is not the case and that responses can be slow, complex and species-specific. The extent of localised fishing pressure appeared to have a substantial influence on the degree of change detected, potentially confounding meta-analyses of recovery rates in MPAs if overlooked as a relevant parameter.  相似文献   

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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   

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王伟  周越  田瑜  李俊生 《生物多样性》2022,30(10):22459-451
建立自然保护地是保护生物多样性最为重要的措施之一。总体来看, 自然保护地生物多样性保护研究主要围绕关键生态系统以及珍稀濒危物种等保护对象的状态以及变化两个层面进行, 并重点关注自然保护地数量与面积、保护了多少重要生态系统和物种、能否有效保护生物多样性等一系列科学问题。然而, 在自然保护地生物多样性保护研究方面, 还缺少针对上述研究领域的系统性综述。为此, 本文系统梳理了自然保护地空间布局及其与生物多样性分布的关系、自然保护地生物多样性变化及其保护成效等近20年来相关领域的研究进展。自然保护地的空间布局以及与生物多样性分布的关系主要围绕自然保护地与生物多样性在某一阶段的状态开展研究, 致力于探究自然保护地“保护多少” “代表性如何” “在哪儿保护”等一系列关键科学问题。同时, 自然保护地内的生物多样性会随着气候变化、人类活动以及自身演替等发生时空动态变化, 基于自然保护地生物多样性变化分析, 各国学者在全球尺度、国家尺度和单个自然保护地进行了大量的保护成效评估研究, 并逐渐发展出了自然保护地内外配对分析方法以提升保护成效评估的精度, 进而识别出不同自然保护地的主要影响因素。在此基础上, 本文进一步对自然保护地生物多样性保护研究提出了展望, 主要包括: (1)综合考虑自然保护地生物多样性状态和变化; (2)开展多目标协同的自然保护地空间优化布局; (3)强化自然保护地主要保护对象的识别、调查与监测; (4)提升自然保护地的质量和连通性; (5)探究自然保护地管理措施与保护成效的关联机制。本文可为“2020年后全球生物多样性框架”的制定与实施特别是在自然保护地体系建设与优化方面提供参考与借鉴。  相似文献   

10.
Ips typographus (Col., Curculionidae, Scolytinae) occurring on Picea abies stems is a species characterised by large fluctuations in population numbers and causing frequent outbreaks. In protected areas, I. typographus is regarded as a sensitive bioindicator responsive to changes in forest health and vitality. In conservation-oriented forestry, attention is being paid to the ecological value of I. typographus beetles as ecosystem engineers and keystone species, driving forest natural regeneration and conversion. Despite many publications devoted to I. typographus, no accurate method for estimating the population density of this species has been developed. The objective of this study was to develop a statistical method for estimating I. typographus population density that enables calculation of estimation errors. The proposed method consists of two parts: tree-level analyses and stand-level analyses. Part one allows calculation of the total density of I. typographus infestation of each of P. abies selected stem (after selecting sample windfalls), part two allows estimation of the mean total infestation density of the stem in the area investigated. Linear regression functions were applied to part one and survey sampling to part two. The method is only marginally invasive because it involves debarking of one 0.5 m-long stem section on maximum 50 P. abies windfalls (trap trees can optionally be used). The developed method was employed to assess I. typographus population density in the ?wi?tokrzyskie Mountains in Central Poland in an area of ca. 4,000 ha. In 2010, in the area investigated, the mean total I. typographus infestation density of the P. abies stem was 440.6 maternal galleries/m2 (from 358.7 to 522.6 maternal galleries/m2 with ?? = 0.05; the relative error of estimation was 18.6%). The examined I. typographus population was in a progradation phase. The proposed method can be used in nature reserves, national parks and managed forests, mainly for scientific purposes.  相似文献   

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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   

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《Trends in biotechnology》1988,6(12):293-298
In this article we will review the ten years' work on cloning with cosmids and reminisce on a most successful collaboration. After 1978, cloning with cosmids became rapidly established worldwide, and has remained the most convenient system for cloning gene-sized fragments from complex genomes and whole operons from microorganisms. We will describe the development and principles of the method emphasizing the use of cosmids for manipulating and shuttling defined units (‘cassettes’) between microorganisms, and subsequently into plants, and in and out of animal cells. We will then discuss the future of the cosmid as an essential tool in the repertoire required for genome analysis and megasequencing.  相似文献   

16.
Background: Atrial fibrillation (AF) is the most common arrhythmia encountered in both male and female patients.Objective: This evidence-based update attempts to address the advances in the science of AF management in light of key gender issues.Methods: In October 2009, 2 investigators (H.I.M. and B.D.P.) independently searched MEDLINE (PubMed [1950–2009] and Ovid [2000–2009]) for all publication types in the English language, using database-specific controlled vocabulary describing the concepts of AF and gender (atrial fibrillation, gender, women, and men for PubMed; atrial fibrillation and gender for Ovid). The reference sections from the identified publications were also used. The methodologic quality of publications, their content relevance, and the authors' expert opinions guided publication inclusion in this evidence-based narrative review. Articles relevant to gender differences in pathophysiology, outcomes, and treatment of AF are summarized and discussed.Results: Based on current available data, mortality is greater for women with AF than for men with AF. Women with AF have a higher risk of stroke compared with their male counterparts. Women derive the greatest benefit from anticoagulation in AF. There are no significant sex differences in major bleeding risk from warfarin. Women tend to be more symptomatic from AF than are men, but fare worse than men when a rhythm-control strategy is utilized with antiarrhythmic medications. Women have an increased risk for torsades de pointes when taking sotalol or dofetilide, and have a higher risk of bradyarrhythmias when taking antiarrhythmics. AF catheter ablation is successful and beneficial for selected patients of both sexes, although women may incur higher procedural bleeding complications. Women tend to be referred for AF ablation less and later than are men.Conclusions: The past decade has witnessed significant progress in the understanding and management of AF. Awareness of key sex-specific differences in AF allows for a more safe, effective, and personalized approach to the management of this disorder.  相似文献   

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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.
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20.
The world's oceans are now attracting the serious attention of conservationists. Paradoxically, as the value of marine biological diversity is recognized, the ecosystems that harbor this diversity are fast becoming degraded. New thinking about how to conserve coastal areas has resulted in protected-area models that incorporate principles of landscape ecology, adaptive and ecosystem management, and zoning in protected-area plans.  相似文献   

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