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Protection of natural environments sought through management plans varies greatly between countries; characterizing these differences and what motivates them can inform future regional and international conservation efforts. This research builds on previous work addressing the spatial distribution of marine protected areas in the Mediterranean Sea. Particularly, it examines the relationship between a “protection level” (PL) score and a set of variables pertaining to each country's conservation efforts, economic conditions and human impact along the coast using regression analysis. Four sets of models demonstrated country characteristics that correlate with higher protection levels within marine protected areas (MPAs). Certain contextual factors – economic dependence on the marine environment, efforts at terrestrial conservation and greater human impact – were found to be significantly associated with higher PLs among the northern littoral countries of the Mediterranean. Such findings can inform policy makers about where efforts and investments should be directed for marine conservation.  相似文献   

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Marine protected areas (MPAs) are attracting widespread attention worldwide as a tool for fishery management and marine ecosystem conservation. The establishment of MPAs has increased greatly in recent years mostly due to international commitments to the establishment of a global network of MPAs by 2012. MPAs have the potential to strongly affect the fishing industry, and their success depends, at least partly, on fishers’ attitudes towards this management measure. However, research on MPAs tends to focus on the ecological and conservation aspects of this management approach and not on its human dimensions. Studies in attitudes, perceptions, beliefs and preferences related to MPA issues have been identified as priority social science topics in need of research. We present a ‘rapid review’, conducted systematically, of the literature published up to September 2009 and aimed at identifying the most investigated topics related to commercial fishers’ attitudes towards MPAs, describing the main findings from these studies, and analysing the implications for management. Most published work focuses on fishers’ attitudes towards issues of governance, conservation of biodiversity and the environment, and the impact of MPAs on fishing activity. Despite the recent increase in the literature on the human dimensions of MPAs, the present review reveals that little of this literature originates from empirical studies. Hence, given the forthcoming increase in the implementation of MPAs in the near future, research on fishers’ attitudes towards these management measures is critically needed.  相似文献   

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The central California coast is visited by millions of people every year, many of whom collect intertidal gastropods for food, bait or recreation in near-shore marine environments. The harvesting of these animals has caused a decline in body size because humans preferentially take the largest individuals. Marine protected areas (MPAs) may serve to protect gastropods from this impact. The average body size and frequency of four gastropod species from eight study locations along the central California coast were determined. Five study locations were in MPAs and three study locations were in non-MPA zones. Gastropods in four California museums were measured and compared to specimens collected in the field. Three of the four species studied were larger and/or more frequent in MPAs than outside MPAs, including both harvested species and one unharvested species. For three of the four species, the average size of individuals from MPA sites was significantly smaller than museum specimens, but this may be due, in part, to our sampling procedure. These findings indicate that MPAs can be effective at reducing human impacts for some species, but that further study is needed to make MPAs as effective as possible for more species.  相似文献   

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Evaluating the effectiveness of protected areas for sustaining biodiversity is crucial to achieving conservation outcomes. While studies of effectiveness have improved our understanding of protected‐area design and management, few investigations (< 5%) have quantified the ecological performance of reserves for conserving species. Here, we present an empirical evaluation of protected‐area effectiveness using long‐term measures of a vulnerable assemblage of species. We compare forest and woodland bird diversity in the Australian Capital Territory over 11 yr on protected and unprotected areas located in temperate eucalypt woodland and matched by key habitat attributes. We examine separately the response of birds to protected areas established prior to 1995 and after 1995 when fundamental changes were made to regional conservation policy. Bird diversity was measured in richness, occurrence of vulnerable species, individual species trajectories and functional trait groups. We found that protected areas were effective in maintaining woody vegetation cover in the study region, but were less effective in the protection of the target bird species assemblage. Protected areas were less species rich than unprotected areas, with significant declines in richness across sites protected prior to 1995. Small, specialised and vulnerable species showed stronger associations with unprotected areas than protected areas. Our findings indicate that recently established reserves (post‐1995) are performing similarly to unprotected woodland areas in terms of maintaining woodland bird diversity, and that both of these areas are more effective in the conservation of woodland bird populations than reserves established prior to 1995. We demonstrate that the conservation value of protected areas is strongly influenced by the physical characteristics, as well as the landscape context, of a given reserve and can diminish with changes in surrounding land use over time. Both protected areas and off‐reserve conservation schemes have important roles to play in securing species populations.  相似文献   

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How are climate and marine biological outbreaks functionally linked?   总被引:5,自引:0,他引:5  
Since the mid-1970s, large-scale episodic events such as disease epidemics, mass mortalities, harmful algal blooms and other population explosions have been occurring in marine environments at an historically unprecedented rate. The variety of organisms involved (host, pathogens and other opportunists) and the absolute number of episodes have also increased during this period. Are these changes coincidental? Between 1972 and 1976, a global climate regime shift took place, and it is manifest most clearly by a change in strength of the North Pacific and North Atlantic pressure systems. Consequences of this regime shift are: (1) prolonged drought conditions in the Sahel region of Africa; (2) increased dust supply to the global atmosphere, by a factor of approximately four; (3) increased easterly trade winds across the Atlantic; (4) increased eolian transport of dust to the Atlantic and Caribbean basins; and (5) increased deposition of iron-rich eolian dust to typically iron-poor marine regions. On the basis of well-documented climate and dust observations and the widely accepted increase in marine outbreak rates, this paper proposes that the increased iron supply has altered the micronutrient factors limiting growth of opportunistic organisms and virulence of pathogenic microbes, particularly in macronutrient-rich coastal systems.  相似文献   

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Recent arguments for conventional fisheries management approaches (CFMAs) and against no-take marine protected areas (NTMPAs) are reviewed, i.e. CFMAs are more effective, density-dependent factors will lead to reduced fish stock production in and around NTMPAs, rights-based approaches in combination with CFMAs will be more effective, and natural refuges from fishing already exist. It is concluded that these are largely valid but only from a fisheries management perspective. The arguments of proponents of NTMPAs and those of proponents of CFMAs are considered as contrasting storylines, the divergences between which are based on two key factors: different objectives and different science. In relation to different objectives, it is concluded that the arguments against NTMPAs based on their lack of fisheries management benefits must be considered as only applying to the secondary resource conservation objectives of such designations and not to the primary marine biodiversity conservation objectives. On this basis it is argued that it is counter-productive for NTMPAs to be ‘sold’ on a win–win basis, including their potential to deliver fisheries management benefits, as this detracts from their marine biodiversity conservation objectives and leaves such calls open to arguments that CFMAs are better able to deliver fisheries management objectives. In relation to different science, it is concluded that criticisms of NTMPAs and support for CFMAs implicitly resist the shift from Mode 1 (reductive, intra-disciplinary) to Mode 2 (holistic, trans-disciplinary) science that is inherent in calls for NTMPAs as part of an ecosystem approach. Mode 2 science attempts to accommodate both uncertainty and wider societal values and preferences, and it is argued that arguments for NTMPAs should be more explicitly focussed on this potential. It is difficult, if not impossible and inappropriate, to extend the reductive approach inherent in CFMA analyses to encompass the broader ethical and scientific concerns for the health of marine ecosystems and their component populations and habitats that arguments for NTMPAs reflect. NTMPA proponents might focus on stressing that arguments against such designations and in favour of CFMAs do not encompass such valid concerns, therefore they tell only half of the story.
P. J. S. JonesEmail:
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To develop effective protected area policies, scholars and practitioners must better understand the mechanisms through which protected areas affect social and environmental outcomes. With strong evidence about mechanisms, the key elements of success can be strengthened, and the key elements of failure can be eliminated or repaired. Unfortunately, empirical evidence about these mechanisms is limited, and little guidance for quantifying them exists. This essay assesses what mechanisms have been hypothesized, what empirical evidence exists for their relative contributions and what advances have been made in the past decade for estimating mechanism causal effects from non-experimental data. The essay concludes with a proposed agenda for building an evidence base about protected area mechanisms.  相似文献   

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The authors review the anticipated benefits from tourism for protected areas in Madagascar, the mechanisms that have been adopted, and how these are working at national and local levels. The contribution of tourism to the maintenance of Protected Areas in Madagascar is assessed. The anticipated benefits of tourism envisaged by the 1991 National Environmental Action Plan are considered to be over-optimistic. The growth rate in tourist arrivals is found to be smaller than previously anticipated as a result of infrastructural constraints at national and local scales. It is suggested that revenues from tourism are inadequate in meeting park management costs although the local transfer of entrance fee revenues to development projects is found to be more beneficial. It is also argued that the benefits of revenue sharing can be effective only for a limited number of protected areas until unfrastructure is improved and protected areas become more accessible to tourists.  相似文献   

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Previous studies from Central Europe and North America showed that species richness is higher in urban than in rural landscapes. Do protected areas, which can be found in both city and countryside, reflect this species richness pattern? The impact of urban land-use might reduce conservation success and necessitate special management strategies. We compared species richness and species spatial turnover of selected animal and plant taxa (carabids, butterflies, snails, birds, lichens, mosses, vascular plants) in 30 protected areas in the city of Halle and 56 protected areas in the adjacent rural district of Saalkreis (Central Germany). Species were mapped by experienced biologists within a systematic species inventory. We corrected species numbers for the effects of landscape structure (e.g. size, shape and distance of habitats) which might influence species diversity beyond urbanisation effects. Butterflies, birds and lichens had significantly higher species numbers in the rural protected areas. Species spatial turnover was higher among urban areas than among rural areas or pairs of urban and rural areas for most taxa. Diversity in all taxa depended on the size of a protected area. We discussed these patterns in the context of the general urban-rural species diversity patterns. Our results indicate an increasing isolation of species assemblages with urbanisation and highlight that space for protected areas is even more limited in urban than rural areas. An effective conservation of urban species diversity should include both typical urban and semi-natural habitats to cover the full range of species living in cities.  相似文献   

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Alzheimer's disease (AD) is a progressive disease of aging primarily characterized at the behavioral level by symptoms of memory loss. The pathological hallmarks of AD are extracellular plaques and intracellular neurofibrillary tangles that are composed of filamentous polymers of beta-amyloid (Abeta) and tau, respectively. Aggregates of filaments are not unique to AD--fibrous polymers are the pathological signatures of many diseases of aging such as Huntington's disease and Parkinson's disease. Whether Abeta or tau filaments cause AD is still an open question, as a wide variety of proteins and pathways have been implicated in the initiation and advancement of the disease--processes such as apoptosis, oxidative stress, and protein degradation. That polymers are the prevalent species observed in aging disorders suggests that this morphology of aggregation represents a significant physiological role. As a consequence of an independent insult or aging itself, the filament shifts from a physiological role to one with pathological implications. The relative importance of Abeta filaments versus tau filaments has also been a focus of significant debate within the research community. Although genetic evidence indicates that Abeta filaments are an integral component in AD, only tau pathology has been found to correlate with symptom presentation in patients. Not only do tau filaments greatly contribute to the systematic loss of neurons and the pathological presentation of memory loss, but they may represent a physiological process whose regulation may be controlled.  相似文献   

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Protected areas (PAs) are an essential tool for the conservation of biodiversity globally. Previous studies have focussed on the effectiveness of PAs and the design of optimal PA networks. However, not all PAs remain intact permanently; many PAs undergo downgrading, downsizing and/or degazettement (PADDD), a fact largely ignored until recently. The drivers of enacted PADDD events and the factors influencing its spatial occurrence are poorly understood, potentially undermining the efficacy of PAs and PA networks. Here we examine the spatial relationship between PADDD and economic, demographic and structural variables, using a 110‐year data set of 342 enacted PADDD events across 44 countries in the tropics and subtropics. We find that the probability of an enacted PADDD event increases with the size of the PA and through a synergistic interaction between PA size and local population densities. Our results are robust to the under‐reporting of enacted PADDD events that occur among smaller PAs and in regions with lower population density. We find an economic motive for PADDD events, given that the opportunity costs associated with larger PAs are higher, on average, than smaller PAs. Our findings suggest a need for conservation practitioners to better consider PA characteristics, as well as the social, economic and political context in which PAs are situated, to aid the creation of more efficient and sustainable PA networks. In particular, the dynamics of enacted PADDD events highlight the need to explicitly consider PA robustness as a core component of systematic conservation planning for PA networks.  相似文献   

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The extension of road networks is considered one of the major factors affecting fauna survival. Roadkill has been documented widely and affects all taxonomic groups. Although roadkill is associated mainly with traffic density, some life-history traits of species and the area surrounding roads are expected to modify number of roadkills both taxonomically and geographically. Here we studied the number of roadkills of vertebrates in an extensive region in the northeastern Iberian Peninsula. We surveyed 820?km of 41 roads in two different seasons (spring and autumn), that differ in traffic intensity. In addition, we covered zones with distinct climatic characteristics and levels of protection of the surrounding habitats. Amphibians showed the highest number of roadkills whereas reptiles, birds and mammals had similar rates. General Linear Model tests showed no differences in roadkills by climatic region; however, differences in number of roadkills were linked to protection status, with the highest number of casualties in highly protected areas. Redundancy Analysis demonstrated that the number of amphibians and reptiles killed was associated with roads in highly protected areas whereas that of mammals and birds was linked to unprotected areas. Protected areas often receive many visitors, which in turn may increase wildlife casualties as a result of greater traffic density. We recommend that correction measures be taken to reduce the high number of vertebrate fauna killed along roads that cross protected areas.  相似文献   

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Although coral declines have been reported from major reefs of the world, region-specific trends still remain unclear, particularly in areas with high diversity such as the Philippines. We assessed the temporal patterns of the magnitude and trajectory of coral cover change in the Philippines using survey data collected from 317 sites. We examined the rate of change in coral cover in relation to time, effects of bleaching and protection against fishing and assessed the efficacy of marine protected areas (MPAs) using meta-analysis. Results showed an overall increase in coral cover in the Philippines from 1981 to 2010. Protection from fishing contributed to the overall increase in the mean annual rate of change as the coral cover significantly increased within MPAs than outside. The significant differences in the rate of coral cover change through time were influenced by chronic anthropogenic stresses, coinciding with the timing of thermal stress and the establishment of MPAs. The rate of change in coral cover was independent of the level of protection and the age and size of MPA.  相似文献   

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Induced or constitutive production of secondary metabolites is a successful plant defence strategy against herbivores which can be mediated by plant associated micro-organisms. Several grass species can be associated with an endophytic fungus of the genus Epichloë which produces herbivore toxic or deterring alkaloids. Besides these direct defences, herbivorous insects are controlled via indirect plant defence mechanisms by attracting predators. Recent studies indicate that Epichloë endophytes can improve the grass emitted volatile organic compounds towards herbivore deterrence. Due to their defensive mutualistic function, we hypothesize that Epichloë altered plant volatiles can attract aphid predators and contribute to an increased indirect plant defence. With a common garden study, we show that hoverfly (Syrphidae) larvae and pupae were more abundant on endophyte-infected plants compared to uninfected plants. Our results indicate that the Epichloë endophyte provides, besides direct defence (alkaloid), indirect plant defence by improving the plant odor attracting more olfactory foraging aphid predators. Future research is needed in order to understand: (I) whether endophyte-mediated changes in plant volatiles are induced herbivore specific, (II) whether there is a trade-off between endophyte-mediated direct and indirect plant defence, (III) whether the endophyte produces volatiles or induces a change in plant-derived volatiles, (IV) the role of plant signals in endophyte-mediated plant defence.  相似文献   

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Coral Reefs - Herbivorous fishes and urchins can contribute to reef resilience by removing algae that are competitive with corals, yet herbivorous fishes are frequently targeted by fishers. The...  相似文献   

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What can biological barcoding do for marine biology?   总被引:1,自引:0,他引:1  
The idea of using nucleotide sequences as barcodes for species identification has stirred up debates in the community of taxonomists and systematists. We argue that barcodes are potentially extremely useful tools for taxonomy for several reasons. Barcodes may, for example, help to identify cryptic and polymorphic species and give means to associate life history stages of unknown identity. Barcode systems would thus be particularly helpful in cases when morphology is ambiguous or uninformative and would provide tools for higher taxonomic resolution of disparate life forms. Comparative analysis of short DNA sequences may also represent heuristic access cards to a deeper understanding of evolutionary relationships between organisms. However, barcodes are the “essence” of species identities no more than taxonomic holotypes are “the species”. It makes no sense to think that morphology and other biological information about organisms can be made obsolete by barcode systems. The biological significance of matching or diverging nucleotide sequences will still have to be the subject of taxonomic decisions that must be open for scrutiny. It is imperative, therefore, that barcodes are associated with specimen vouchers.  相似文献   

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