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Cassar Michelle 《Journal of Coastal Conservation》2003,9(1):73-80
This paper examines a 3-yr EU LIFE-funded project for the management of two especially protected areas on the Maltese coast.
Project partners are the Euro-Mediterranean Centre on Insular Coastal Dynamics (ICoD), the Gaia Foundation and the Ministry
for the Environment of Malta.
Project sites are the Ghajn Tuffieha area on the northwest coast of Malta, and the Ramla Bay area on the island of Gozo. While
both sites are in a relatively pristine state and comprise a number of features of ecological and scientific importance, they
are also prime recreational areas, hosting thousands of visitors especially during the summer months. The challenge is to
manage these sites in a sustainable manner in order to protect their unique ecology while simultaneously controlling and managing
the human activities taking place there.
The following sequence of activities is being implemented at both sites: surveys of the resources present (biodiversity, habitats,
geological and hydrological features, and archaeological heritage), implementation of first intervention measures, and the
drawing up and implementation of site-specific management plans, including rehabilitation and protection of biodiversity and
habitats, regulations for site use, and awareness raising and educational measures.
The management structure of this project supports the concept of decentralization of management of protected areas, through
the granting of responsibility for the direct management of these sites to a non-governmental organization, under joint government/EU
funding. This paper thus presents the project as a model for similar initiatives for the management of protected sites in
the Mediterranean. 相似文献
3.
In order to properly determine the efficacy of marine protected areas (MPAs), a seascape perspective that integrates ecosystem elements at the appropriate ecological scale is necessary. Over the past four decades, Hawaii has developed a system of 11 Marine Life Conservation Districts (MLCDs) to conserve and replenish marine resources around the state. Initially established to provide opportunities for public interaction with the marine environment, these MLCDs vary in size, habitat quality, and management regimes, providing an excellent opportunity to test hypotheses concerning MPA design and function using multiple discrete sampling units. Digital benthic habitat maps for all MLCDs and adjacent habitats were used to evaluate the efficacy of existing MLCDs using a spatially explicit stratified random sampling design. Analysis of benthic cover validated the a priori classification of habitat types and provided justification for using these habitat strata to conduct stratified random sampling and analyses of fish habitat utilization patterns. Results showed that a number of fish assemblage characteristics (e.g., species richness, biomass, diversity) vary among habitat types, but were significantly higher in MLCDs compared with adjacent fished areas across all habitat types. Overall fish biomass was 2.6 times greater in the MLCDs compared to open areas. In addition, apex predators and other species were more abundant and larger in the MLCDs, illustrating the effectiveness of these closures in conserving fish populations within their boundaries. Habitat type, protected area size, and level of protection from fishing were all important determinates of MLCD effectiveness with respect to their associated fish assemblages. Although size of these protected areas was positively correlated with a number of fish assemblage characteristics, all appear too small to have any measurable influence on the adjacent fished areas. These protected areas were not designed for biodiversity conservation or fisheries enhancement yet still provide varying degrees of protection for fish populations within their boundaries. Implementing this type of biogeographic process, using remote sensing technology and sampling across the range of habitats present within the seascape, provides a robust evaluation of existing MPAs and can help to define ecologically relevant boundaries for future MPA design in a range of locations. 相似文献
4.
Elasmobranch stock assessment studies are usually made through fisheries surveys data. However, in large marine protected
areas (MPAs) the use of destructive techniques must be dismissed in order to avoid population impacts. In 2005, while conducting
a marine habitat survey in two marine Special Areas of Conservation (Sebadales de Playa de Inglés and Franja Marina de Mogán)
in south Gran Canary Island (Canary Islands, Spain) with underwater towed video (UTV) and underwater visual census (UVC) transects,
we recognized the opportunity rose to assess elasmobranch populations through UTV. Number of observed species and specimens,
overall field work effort and total surveyed area were determined and compared between methods. Mean observations per day
per unit of time (MOPUT) and mean observations per day per unit of surveyed area (MOPUA) were also compared through Mann–Whitney
rank sum statistical test (α = 0.05). Data analysis demonstrated that UTV is a very useful tool to rapidly assess elasmobranch
populations in large MPAs in good visibility underwater environments. It can assess larger areas than UVC with the same effort
(statistically significant difference found for the MOPUT; p =< 0.001), leading to more observed species (5 vs 2) and specimens (46 vs 3) per day of work, with no loss in resolution power (MOPUA values were not significantly different between UTV and UVC;
p = 0.104). 相似文献
5.
Managing conflicts between economic activities and threatened migratory marine species toward creating a multiobjective blue economy
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Linda R. Harris Ronel Nel Herman Oosthuizen Mike Meÿer Deon Kotze Darrell Anders Steven McCue Santosh Bachoo 《Conservation biology》2018,32(2):411-423
Harnessing the economic potential of the oceans is key to combating poverty, enhancing food security, and strengthening economies. But the concomitant risk of intensified resource extraction to migratory species is worrying given these species contribute to important ecological processes, often underpin alternative livelihoods, and are mostly already threatened. We thus sought to quantify the potential conflict between key economic activities (5 fisheries and hydrocarbon exploitation) and sea turtle migration corridors in a region with rapid economic development: southern and eastern Africa. We satellite tracked the movement of 20 loggerhead (Caretta caretta) and 14 leatherback (Dermochelys coriacea) turtles during their postnesting migrations. We used movement‐based kernel density estimation to identify migration corridors for each species. We overlaid these corridors on maps of the distribution and intensity of economic activities, quantified the extent of overlap and threat posed by each activity on each species, and compared the effects of activities. These results were compared with annual bycatch rates in the respective fisheries. Both species’ 3 corridors overlapped most with longline fishing, but the effect was worse for leatherbacks: their bycatch rates of approximately 1500/year were substantial relative to the regional population size of <100 nesting females/annum. This bycatch rate is likely slowing population growth. Artisanal fisheries may be of greater concern for loggerheads than for leatherbacks, but the population appears to be withstanding the high bycatch rates because it is increasing exponentially. The hydrocarbon industry currently has a moderately low impact on both species, but mining in key areas (e.g., Southern Mozambique) may undermine >50 years of conservation, potentially affecting >80% of loggerheads, 33% of the (critically endangered) leatherbacks, and their nesting beaches. We support establishing blue economies (i.e., generating wealth from the ocean), but oceans need to be carefully zoned and responsibly managed in both space and time to achieve economic (resource extraction), ecological (conservation, maintenance of processes), and social (maintenance of alternative livelihood opportunities, alleviate poverty) objectives. 相似文献
6.
João B. Teixeira Rodrigo L. Moura Morena Mills Carissa Klein Christopher J. Brown Vanessa M. Adams Hedley Grantham Matthew Watts Deborah Faria Gilberto M. Amado‐Filho Alex C. Bastos Reinaldo Lourival Hugh P. Possingham 《Conservation biology》2018,32(5):1096-1106
Although marine protected areas can simultaneously contribute to biodiversity conservation and fisheries management, the global network is biased toward particular ecosystem types because they have been established primarily in an ad hoc fashion. The optimization of trade‐offs between biodiversity benefits and socioeconomic values increases success of protected areas and minimizes enforcement costs in the long run, but it is often neglected in marine spatial planning (MSP). Although the acquisition of spatially explicit socioeconomic data is perceived as a costly or secondary step in MSP, it is critical to account for lost opportunities by people whose activities will be restricted, especially fishers. We developed an easily reproduced habitat‐based approach to estimate the spatial distribution of opportunity cost to fishers in data‐poor regions. We assumed the most accessible areas have higher economic and conservation values than less accessible areas and their designation as no‐take zones represents a loss of fishing opportunities. We estimated potential distribution of fishing resources from bathymetric ranges and benthic habitat distribution and the relative importance of the different resources for each port of total catches, revenues, and stakeholder perception. In our model, we combined different cost layers to produce a comprehensive cost layer so that we could evaluate of trade‐offs. Our approach directly supports conservation planning, can be applied generally, and is expected to facilitate stakeholder input and community acceptance of conservation. 相似文献
7.
Tools for comprehensive estimate of coastal region marine economy potential and its use for coastal planning 总被引:1,自引:0,他引:1
George Gogoberidze 《Journal of Coastal Conservation》2012,16(3):251-260
For elaboration of strategy and spatial planning of sustainable coastal regions development it??s very important to know a real potential of development of the region. As parameter, which is comprehensively characterized marine economic, political and military power of the coastal region, it is possible to use the marine economy potential with comprehensive estimations of socio-economic, political, environment and military profits (damages) from coastal planning decisions. Some results, including the European and Russian coastal regions are presented. 相似文献
8.
Regime shift in a coastal marine ecosystem 总被引:1,自引:0,他引:1
Jens Kjerulf Petersen Jens Würgler Hansen Martha Brogaard Laursen Preben Clausen Jacob Carstensen Daniel J Conley 《Ecological applications》2008,18(2):497-510
We demonstrate changes in ecosystem stable states in a coastal lagoon that are consistent with what a regime shift would hypothesize. In the nutrient-stressed Ringk?bing Fjord, Denmark, a small change in one variable (salinity) facilitated by a change in sluice management, caused a sudden regime shift from a bottom-up controlled turbid state, into a top-down controlled clear-water state. The change in dominating pathway of organic matter production from pelagic turnover to benthic-pelagic coupling was facilitated by new recruitment and growth of existing suspension-feeding clams, Mya arenaria. With the invasion of clams, benthic grazing became the key feature of the biological structure. Phytoplankton composition and zooplankton abundance were also affected by the change in biological structure. The small, but sudden, increase in salinity caused by the change in sluice management led to a dramatic reduction in biomass and coverage of benthic vegetation and thus affected herbivorous waterbird populations. In recent years, plant coverage has been increasing, as can be expected with increased water transparency. The regime shift has some major implications for coastal water management and revealed some conflicts between different types of nature and environmental protection legislation. 相似文献
9.
Toward pristine biomass: reef fish recovery in coral reef marine protected areas in Kenya. 总被引:2,自引:0,他引:2
Tim R McClanahan Nicholas A J Graham Jacqulyn M Calnan M Aaron MacNeil 《Ecological applications》2007,17(4):1055-1067
Identifying the rates of recovery of fish in no-take areas is fundamental to designing protected area networks, managing fisheries, estimating yields, identifying ecological interactions, and informing stakeholders about the outcomes of this management. Here we study the recovery of coral reef fishes through 37 years of protection using a space-for-time chronosequence of four marine national parks in Kenya. Using AIC model selection techniques, we assessed recovery trends using five ecologically meaningful production models: asymptotic, Ricker, logistic, linear, and exponential. There were clear recovery trends with time for species richness, total and size class density, and wet masses at the level of the taxonomic family. Species richness recovered rapidly to an asymptote at 10 years. The two main herbivorous families displayed differing responses to protection, scarids recovering rapidly, but then exhibiting some decline while acanthurids recovered more slowly and steadily throughout the study. Recovery of the two invertebrate-eating groups suggested competitive interactions over resources, with the labrids recovering more rapidly before a decline and the balistids demonstrating a slower logistic recovery. Remaining families displayed differing trends with time, with a general pattern of decline in smaller size classes or small-bodied species after an initial recovery, which suggests that some species- and size-related competitive and predatory control occurs in older closures. There appears to be an ecological succession of dominance with an initial rapid rise in labrids and scarids, followed by a slower rise in balistids and acanthurids, an associated decline in sea urchins, and an ultimate dominance in calcifying algae. Our results indicate that the unfished "equilibrium" biomass of the fish assemblage > 10 cm is 1100-1200 kg/ha, but these small parks (< 10 km2) are likely to underestimate pre-human influence values due to edge effects and the rarity of taxa with large area requirement, such as apex predators, including sharks. 相似文献
10.
Fishing‐gear restrictions and biomass gains for coral reef fishes in marine protected areas
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Stuart J. Campbell Graham J. Edgar Rick D. Stuart‐Smith German Soler Amanda E. Bates 《Conservation biology》2018,32(2):401-410
Considerable empirical evidence supports recovery of reef fish populations with fishery closures. In countries where full exclusion of people from fishing may be perceived as inequitable, fishing‐gear restrictions on nonselective and destructive gears may offer socially relevant management alternatives to build recovery of fish biomass. Even so, few researchers have statistically compared the responses of tropical reef fisheries to alternative management strategies. We tested for the effects of fishery closures and fishing gear restrictions on tropical reef fish biomass at the community and family level. We conducted 1,396 underwater surveys at 617 unique sites across a spatial hierarchy within 22 global marine ecoregions that represented 5 realms. We compared total biomass across local fish assemblages and among 20 families of reef fishes inside marine protected areas (MPAs) with different fishing restrictions: no‐take, hook‐and‐line fishing only, several fishing gears allowed, and sites open to all fishing gears. We included a further category representing remote sites, where fishing pressure is low. As expected, full fishery closures, (i.e., no‐take zones) most benefited community‐ and family‐level fish biomass in comparison with restrictions on fishing gears and openly fished sites. Although biomass responses to fishery closures were highly variable across families, some fishery targets (e.g., Carcharhinidae and Lutjanidae) responded positively to multiple restrictions on fishing gears (i.e., where gears other than hook and line were not permitted). Remoteness also positively affected the response of community‐level fish biomass and many fish families. Our findings provide strong support for the role of fishing restrictions in building recovery of fish biomass and indicate important interactions among fishing‐gear types that affect biomass of a diverse set of reef fish families. 相似文献
11.
Leigh M. Howarth Howard L. Wood Alexander P. Turner Bryce D. Beukers-Stewart 《Marine Biology》2011,158(8):1767-1780
This study investigated the effects of a fully protected marine reserve on commercially valuable scallops and benthic habitats in Lamlash Bay, Isle of Arran, United Kingdom. Dive surveys found the abundance of juvenile scallops to be greater within the marine reserve than outside. A novel multivariate approach, based upon neural networks and generalised linear models, revealed the greater abundance of juveniles to be related to the greater presence of macroalgae and maerl within the reserve boundaries. This complex habitat appeared to have positively encouraged spat settlement. In contrast, the density of adult scallops did not differ between the two treatments, possibly due to the short duration of protection. However, the age, size and biomass of adult scallops were significantly greater within the reserve. Overall, this study suggests that the newly created marine reserve is already providing benefits which are flowing back to species targeted by fisheries, emphasising the importance of marine reserves in ecosystem-based management of fisheries. 相似文献
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The major pigment of a marine micro-organism was identified as prodigiosin on the basis of analytical and spectral data. Two minor pigments were tentatively assigned structures, from thin-layer chromatography (TLC) and mass spectral data, as prodigiosin homologs with 3-n-hexyl and 3-n-heptyl side-chains. The micro-organism was classified as a new Pseudomonas species on the basis of its morphological and biochemical characteristics. It was named Pseudomonas magnesiorubra (ATCC No. 21856). 相似文献
14.
Land use change around protected areas: management to balance human needs and ecological function. 总被引:6,自引:0,他引:6
Ruth DeFries Andrew Hansen B L Turner Robin Reid Jianguo Liu 《Ecological applications》2007,17(4):1031-1038
Protected areas throughout the world are key for conserving biodiversity, and land use is key for providing food, fiber, and other ecosystem services essential for human sustenance. As land use change isolates protected areas from their surrounding landscapes, the challenge is to identify management opportunities that maintain ecological function while minimizing restrictions on human land use. Building on the case studies in this Invited Feature and on ecological principles, we identify opportunities for regional land management that maintain both ecological function in protected areas and human land use options, including preserving crucial habitats and migration corridors, and reducing dependence of local human populations on protected area resources. Identification of appropriate and effective management opportunities depends on clear definitions of: (1) the biodiversity attributes of concern; (2) landscape connections to delineate particular locations with strong ecological interactions between the protected area and its surrounding landscape; and (3) socioeconomic dynamics that determine current and future use of land resources in and around the protected area. 相似文献
15.
Dirac Twidwell Carissa L. Wonkka Christine H. Bielski Craig R. Allen David G. Angeler Jacob Drozda Ahjond S. Garmestani Julia Johnson Larkin A. Powell Caleb P. Roberts 《Conservation biology》2018,32(4):905-915
A modern challenge for conservation biology is to assess the consequences of policies that adhere to assumptions of stationarity (e.g., historic norms) in an era of global environmental change. Such policies may result in unexpected and surprising levels of mitigation given future climate‐change trajectories, especially as agriculture looks to protected areas to buffer against production losses during periods of environmental extremes. We assessed the potential impact of climate‐change scenarios on the rates at which grasslands enrolled in the Conservation Reserve Program (CRP) are authorized for emergency harvesting (i.e., biomass removal) for agricultural use, which can occur when precipitation for the previous 4 months is below 40% of the normal or historical mean precipitation for that 4‐month period. We developed and analyzed scenarios under the condition that policy will continue to operate under assumptions of stationarity, thereby authorizing emergency biomass harvesting solely as a function of precipitation departure from historic norms. Model projections showed the historical likelihood of authorizing emergency biomass harvesting in any given year in the northern Great Plains was 33.28% based on long‐term weather records. Emergency biomass harvesting became the norm (>50% of years) in the scenario that reflected continued increases in emissions and a decrease in growing‐season precipitation, and areas in the Great Plains with higher historical mean annual rainfall were disproportionately affected and were subject to a greater increase in emergency biomass removal. Emergency biomass harvesting decreased only in the scenario with rapid reductions in emissions. Our scenario‐impact analysis indicated that biomass from lands enrolled in the CRP would be used primarily as a buffer for agriculture in an era of climatic change unless policy guidelines are adapted or climate‐change projections significantly depart from the current consensus. 相似文献
16.
Effectiveness of Africa's tropical protected areas for maintaining forest cover 总被引:1,自引:0,他引:1
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The effectiveness of parks for forest conservation is widely debated in Africa, where increasing human pressure, insufficient funding, and lack of management capacity frequently place significant demands on forests. Tropical forests house a substantial portion of the world's remaining biodiversity and are heavily affected by anthropogenic activity. We analyzed park effectiveness at the individual (224 parks) and national (23 countries) level across Africa by comparing the extent of forest loss (as a proxy for deforestation) inside parks to matched unprotected control sites. Although significant geographical variation existed among parks, the majority of African parks had significantly less forest loss within their boundaries (e.g., Mahale Park had 34 times less forest loss within its boundary) than control sites. Accessibility was a significant driver of forest loss. Relatively inaccessible areas had a higher probability (odds ratio >1, p < 0.001) of forest loss but only in ineffective parks, and relatively accessible areas had a higher probability of forest loss but only in effective parks. Smaller parks less effectively prevented forest loss inside park boundaries than larger parks (T = ?2.32, p < 0.05), and older parks less effectively prevented forest loss inside park boundaries than younger parks (F2,154 = ?4.11, p < 0.001). Our analyses, the first individual and national assessment of park effectiveness across Africa, demonstrated the complexity of factors (such as geographical variation, accessibility, and park size and age) influencing the ability of a park to curb forest loss within its boundaries. 相似文献
17.
Grewell BJ 《Ecology》2008,89(6):1481-1488
Outbreaks of infectious agents in natural ecosystems are on the rise. Understanding host-pathogen interactions and their impact on community composition may be central to the conservation of biological diversity. Infectious agents can convey both exploitive and facilitative effects that regulate host populations and community structure. Parasitic angiosperms are highly conspicuous in many plant communities, and they provide a tractable model for understanding parasite effects in multispecies communities. I examined host identity and variation in host infectivity of a holoparasitic vine (Cuscuta salina) within a California salt marsh. In a two-year parasite removal experiment, I measured the effect of C. salina on its most frequent host, a rare hemiparasite, and the plant community. C. salina clearly suppressed the dominant host, but rare plant fitness and plant species diversity were enhanced through indirect effects. Priority effects played a role in the strength of the outcome due to the timing of life history characteristics. The differential influence of parasites on the fecundity of multiple hosts can change population dynamics, benefit rare species, and alter community structure. The continuum of negative to positive consequences of parasitic interactions deserves more attention if we are to understand community dynamics and successfully restore tidal wetlands. 相似文献
18.
Assessing carrying capacities of coastal areas in France 总被引:1,自引:0,他引:1
This paper provides the methodological framework for carrying capacity assessment through a set of indicators, as implemented
in a French case study. The approach aims to help the State and local governments of coastal areas facing population growth
and important touristic flows to undergo a local development strategy that does not imperil their territorial strategic resources.
This work shows how situations of dysfunction or saturation points have interlinked consequences on environmental, social
and economic resources, justifying a crosswise assessment. 相似文献
19.
Freshwater protected areas are rare even though freshwater ecosystems are among the most imperiled in the world. Conservation actions within terrestrial protected areas (TPAs) such as development or resource extraction regulations may spill over to benefit freshwater ecosystems within their boundaries. Using data from 175 lakes across Ontario, Canada, we compared common indicators of fish‐assemblage status (i.e., species richness, Shannon diversity index, catch per unit effort, and normalized‐length size spectrum slopes) to evaluate whether TPAs benefit lake fish assemblages. Nearest neighbor cluster analysis was used to generate pairs of lakes: inside versus outside, inside versus bordering, and bordering versus outside TPAs based on lake characteristics. The diversity and abundance indicators did not differ significantly across comparisons, but normalized‐length size spectrum slopes (NLSS) were significantly steeper in lakes outside parks. The latter indicated assemblage differences (greater abundances of small‐bodied species) and less‐efficient energy transfer through the trophic levels of assemblages outside parks. Although not significantly different, pollution‐ and turbidity‐tolerant species were more abundant outside parks, whereas 3 of the 4 pollution‐intolerant species were more abundant within parks. Twenty‐one percent of the difference in slopes was related to higher total dissolved solids concentrations and angling pressure. Our results support the hypothesis that TPAs benefit lake fish assemblages and suggest that NLSS slopes are informative indicators for aquatic protected area evaluations because they represent compositional and functional aspects of communities. 相似文献
20.
The area between the island of Capri and Punta Campanella was investigated from June to November 2003. Punta Campanella separates the Gulf of Naples from the Gulf of Salerno and has been declared a marine protected area in 1997. The study area has a particular interesting topography, due to the presence of a sill situated at a depth of 80 m. Samples were collected by instruments carried on a mooring array (sediment trap, current meters, and temperature sensors) and by CTD cast (along transects perpendicular to the coast). We observed most important fluctuations in the temperature spectra (corresponding to the inertial oscillations period), in August. The total mass flux was 585.67 mg m-2 d-1 in the summer, while in early autumn the flux exhibited values one order of magnitude higher than in summer (1539.97 mg m-2 d-1). The main focus of this study was to understand the influence of the internal waves on the particle flux. During the autumn, in the particle flux collected, there is a strong resuspension component, and the observation that the enhanced inertial oscillations and increased sedimentation occur at the same time allows us to presume that the inertial oscillations could be one of the reasons for the resuspension process during the sampling period. 相似文献