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1.
Zootaxa ; 4588(1): zootaxa.4588.1.1, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31716112

RESUMO

A checklist of the marine and estuarine fishes of New Ireland Province is presented, with special emphasis on Kavieng District, combining both previous and new records. After the recent KAVIENG 2014 expedition, a total of 1325 species in 153 families were recorded from the region. The largest families are the Gobiidae, Pomacentridae, Labridae, Serranidae, Apogonidae, Lutjanidae, Chaetodontidae, Blenniidae, Carangidae, Acanthuridae, Scaridae, Holocentridae, Syn-gnathidae, Lethrinidae and Scorpaenidae. A total of 810 fish species (61.1 % of the total marine and estuarine fish fauna) are recorded from New Ireland for the first time.The fish fauna of New Ireland includes 142 species in transitional waters and 1264 species in marine habitats, and 54 species species in freshwater habitats. Zoogeographically, 1179 species have a wide distribution range, most frequently a broad Indo-West Pacific distribution. Among the remaining species, just 12 are endemic to New Ireland.


Assuntos
Perciformes , Animais , Ecossistema , Oceano Pacífico , Papua Nova Guiné
2.
Mar Pollut Bull ; 131(Pt B): 83-95, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29096976

RESUMO

In Bunaken Island (Indonesia), a time-series of very high resolution (2-4m) satellite imagery was used to draw the long-term dynamics of shallow reef flat habitats from 2001 to 2015. Lack of historical georeferenced ground-truth data oriented the analysis towards a scenario-approach based on the monitoring of selected unambiguously-changing habitat polygons characterized in situ in 2014 and 2015. Eight representative scenarios (coral colonization, coral loss, coral stability, and sand colonization by seagrass) were identified. All occurred simultaneously in close vicinity, precluding the identification of a single general cause of changes that could have affected the whole reef. Likely, very fine differences in reef topography, exposure to wind/wave and sea level variations were responsible for the variety of trajectories. While trajectories of reef habitats is a way to measure resilience and coral recovery, here, the 15-year time-series was too short to be able to conclude on the resilience of Bunaken reefs.


Assuntos
Recifes de Corais , Ecossistema , Animais , Indonésia , Ilhas , Comunicações Via Satélite
3.
Mar Pollut Bull ; 131(Pt B): 72-82, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29054770

RESUMO

The Coral Triangle is the epicenter of marine biodiversity, yet the numbers of habitats that can be found on coral reefs remain poorly described. First surveys for habitat mapping in Indonesia revealed a high number of habitats (>150) even for structurally simple reefs. To be able to represent all these habitats, typical habitat mapping procedures and performances are poorly effective even using very high resolution satellite images. Using Bunaken Island (North Sulawesi, Indonesia) as a case study, we devised a way to maintain all the in situ habitat information in remote sensing habitat map products without loss and with mapping procedures based on photo-interpretation. The result is a product which is consistent with a per-polygon fuzzy classification. As such, it is a complex product that meets our habitat representation goal, but its complexity can also limit its immediate use by managers and conservation planners when analyses per habitat are needed.


Assuntos
Antozoários , Ecossistema , Tecnologia de Sensoriamento Remoto , Animais , Conservação dos Recursos Naturais/métodos , Indonésia , Ilhas
4.
Theor Popul Biol ; 119: 37-47, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29158140

RESUMO

Despite actions to manage sustainably tropical Pacific Ocean reef fisheries, managers have faced failures and frustrations because of unpredicted mass mortality events triggered by climate variability. The consequences of these events on the long-term population dynamics of living resources need to be better understood for better management decisions. Here, we use a giant clam (Tridacna maxima) spatially explicit population model to compare the efficiency of several management strategies under various scenarios of natural mortality, including mass mortality due to climatic anomalies. The model was parameterized by in situ estimations of growth and mortality and fishing effort, and was validated by historical and new in situ surveys of giant clam stocks in two French Polynesia lagoons. Projections on the long run (100 years) suggested that the best management strategy was a decrease of fishing pressure through quota implementation, regardless of the mortality regime considered. In contrast, increasing the minimum legal size of catch and closing areas to fishing were less efficient. When high mortality occurred due to climate variability, the efficiency of all management scenarios decreased markedly. Simulating El Niño Southern Oscillation event by adding temporal autocorrelation in natural mortality rates increased the natural variability of stocks, and also decreased the efficiency of management. These results highlight the difficulties that managers in small Pacific islands can expect in the future in the face of global warming, climate anomalies and new mass mortalities.


Assuntos
Bivalves/crescimento & desenvolvimento , Clima , Animais , Pesqueiros , Oceano Pacífico , Dinâmica Populacional , Incerteza
5.
PLoS One ; 12(5): e0178239, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542261

RESUMO

Previous seascape genetics studies have emphasized the role of ocean currents and geographic distances to explain the genetic structure of marine species, but the role of benthic habitat has been more rarely considered. Here, we compared the population genetic structure observed in West Pacific giant clam populations against model simulations that accounted habitat composition and configuration, geographical distance, and oceanic currents. Dispersal determined by geographical distance provided a modelled genetic structure in better agreement with the observations than dispersal by oceanic currents, possibly due to insufficient spatial resolution of available oceanographic and coastal circulation models. Considering both habitat composition and configuration significantly improved the match between simulated and observed genetic structures. This study emphasizes the importance of a reefscape genetics approach to population ecology, evolution and conservation in the sea.


Assuntos
Organismos Aquáticos/genética , Bivalves/genética , Recifes de Corais , Animais , Organismos Aquáticos/fisiologia , Bivalves/fisiologia , Demografia , Ecossistema , Modelos Biológicos , Nova Caledônia , Oceanos e Mares , Vanuatu
6.
PLoS One ; 12(1): e0170565, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28118406

RESUMO

Shell growth, reproduction, and natural mortality of the giant clam Tridacna maxima were characterized over a two-year-period in the lagoon of the high island of Tubuai (Austral Archipelago) and in the semi-closed lagoon of Tatakoto (Tuamotu Archipelago) in French Polynesia. We also recorded temperature, water level, tidal slope, tidal range, and mean wave height in both lagoons. Lower lagoon aperture and exposure to oceanic swells at Tatakoto than at Tubuai was responsible for lower lagoon water renewal, as well as higher variability in temperature and water level at Tatakoto across the studied period. These different environmental conditions had an impact on giant clams. Firstly, spawning events in the lagoon of Tatakoto, detected by gonad maturity indices in June and July 2014, were timed with high oceanic water inflow and a decrease in lagoon water temperature. Secondly, temperature explained differences in shell growth rates between seasons and lagoons, generating different growth curves for the two sites. Thirdly, local mortality rates were also found to likely be related to water renewal patterns. In conclusion, our study suggests that reef aperture and lagoon water renewal rates play an integral role in giant clam life history, with significant differences in rates of shell growth, mortality and fertility found between open versus semi-closed atoll lagoons in coral reef ecosystems.


Assuntos
Bivalves/fisiologia , Ecossistema , Exoesqueleto/crescimento & desenvolvimento , Animais , Bivalves/crescimento & desenvolvimento , Recifes de Corais , Feminino , Fertilidade , Masculino , Polinésia , Reprodução , Estações do Ano , Água do Mar , Análise de Sobrevida , Temperatura Ambiente , Movimentos da Água , Vento
7.
Curr Biol ; 27(1): 149-154, 2017 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-27989671

RESUMO

The degree to which offspring remain near their parents or disperse widely is critical for understanding population dynamics, evolution, and biogeography, and for designing conservation actions. In the ocean, most estimates suggesting short-distance dispersal are based on direct ecological observations of dispersing individuals, while indirect evolutionary estimates often suggest substantially greater homogeneity among populations. Reconciling these two approaches and their seemingly competing perspectives on dispersal has been a major challenge. Here we show for the first time that evolutionary and ecological measures of larval dispersal can closely agree by using both to estimate the distribution of dispersal distances. In orange clownfish (Amphiprion percula) populations in Kimbe Bay, Papua New Guinea, we found that evolutionary dispersal kernels were 17 km (95% confidence interval: 12-24 km) wide, while an exhaustive set of direct larval dispersal observations suggested kernel widths of 27 km (19-36 km) or 19 km (15-27 km) across two years. The similarity between these two approaches suggests that ecological and evolutionary dispersal kernels can be equivalent, and that the apparent disagreement between direct and indirect measurements can be overcome. Our results suggest that carefully applied evolutionary methods, which are often less expensive, can be broadly relevant for understanding ecological dispersal across the tree of life.


Assuntos
Evolução Biológica , Ecossistema , Perciformes/genética , Distribuição Animal , Animais , Genética Populacional , Larva/fisiologia , Perciformes/crescimento & desenvolvimento , Perciformes/fisiologia , Dinâmica Populacional , Fatores de Tempo
8.
PLoS One ; 11(11): e0164869, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27829042

RESUMO

Spatial data characteristics have the potential to influence various aspects of prioritising biodiversity areas for systematic conservation planning. There has been some exploration of the combined effects of size of planning units and level of classification of physical environments on the pattern and extent of priority areas. However, these data characteristics have yet to be explicitly investigated in terms of their interaction with different socioeconomic cost data during the spatial prioritisation process. We quantify the individual and interacting effects of three factors-planning-unit size, thematic resolution of reef classes, and spatial variability of socioeconomic costs-on spatial priorities for marine conservation, in typical marine planning exercises that use reef classification maps as a proxy for biodiversity. We assess these factors by creating 20 unique prioritisation scenarios involving combinations of different levels of each factor. Because output data from these scenarios are analogous to ecological data, we applied ecological statistics to determine spatial similarities between reserve designs. All three factors influenced prioritisations to different extents, with cost variability having the largest influence, followed by planning-unit size and thematic resolution of reef classes. The effect of thematic resolution on spatial design depended on the variability of cost data used. In terms of incidental representation of conservation objectives derived from finer-resolution data, scenarios prioritised with uniform cost outperformed those prioritised with variable cost. Following our analyses, we make recommendations to help maximise the spatial and cost efficiency and potential effectiveness of future marine conservation plans in similar planning scenarios. We recommend that planners: employ the smallest planning-unit size practical; invest in data at the highest possible resolution; and, when planning across regional extents with the intention of incidentally representing fine-resolution features, prioritise the whole region with uniform costs rather than using coarse-resolution data on variable costs.


Assuntos
Antozoários/fisiologia , Conservação dos Recursos Naturais/economia , Recifes de Corais , Pesqueiros/economia , Animais , Antozoários/classificação , Organismos Aquáticos/classificação , Organismos Aquáticos/fisiologia , Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecologia/economia , Ecologia/métodos , Fiji , Peixes/classificação , Peixes/fisiologia , Mapeamento Geográfico , Geografia , Biologia Marinha/economia , Micronésia
9.
Mar Pollut Bull ; 100(1): 359-369, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26342390

RESUMO

Since its description in 1984, little attention has been paid to the New Caledonian endemic mushroom coral Cantharellus noumeae (Fungiidae), an IUCN Red-listed, endangered coral species. Our study presents the first ever quantitative assessment conducted on C. noumeae populations for two contrasting sites in the same turbid bay. Sites differed by their substrates of artificial or natural origins. Metal concentrations of superficial sediment were measured. C. noumeae was found in high densities in metal-rich and turbid environments at both locations, reaching up to 288 individuals per 50m(2). It was 3.5 times more abundant on natural rock than on artificial substrates. Recruitment was also higher proportionally on rock (47% vs 7-14%). The composition of the associated coral communities included 30-37 species occurring in low densities. Our findings clarify the environmental niche of this species and its colonization potential, in order to eventually better characterize its conservation status.


Assuntos
Agaricales/fisiologia , Antozoários/fisiologia , Animais , Baías , Ecossistema , Espécies em Perigo de Extinção , Metais , Nova Caledônia
10.
PLoS One ; 10(8): e0135789, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26288089

RESUMO

Locally-established marine protected areas (MPAs) have been proven to achieve local-scale fisheries and conservation objectives. However, since many of these MPAs were not designed to form ecologically-connected networks, their contributions to broader-scale goals such as complementarity and connectivity can be limited. In contrast, integrated networks of MPAs designed with systematic conservation planning are assumed to be more effective--ecologically, socially, and economically--than collections of locally-established MPAs. There is, however, little empirical evidence that clearly demonstrates the supposed advantages of systematic MPA networks. A key reason is the poor record of implementation of systematic plans attributable to lack of local buy-in. An intermediate scenario for the expansion of MPAs is scaling up of local decisions, whereby locally-driven MPA initiatives are coordinated through collaborative partnerships among local governments and their communities. Coordination has the potential to extend the benefits of individual MPAs and perhaps to approach the potential benefits offered by systematic MPA networks. We evaluated the benefits of scaling up local MPAs to form networks by simulating seven expansion scenarios for MPAs in the Verde Island Passage, central Philippines. The scenarios were: uncoordinated community-based establishment of MPAs; two scenarios reflecting different levels of coordinated MPA expansion through collaborative partnerships; and four scenarios guided by systematic conservation planning with different contexts for governance. For each scenario, we measured benefits through time in terms of achievement of objectives for representation of marine habitats. We found that: in any governance context, systematic networks were more efficient than non-systematic ones; systematic networks were more efficient in broader governance contexts; and, contrary to expectations but with caveats, the uncoordinated scenario was slightly more efficient than the coordinated scenarios. Overall, however, coordinated MPA networks have the potential to be more efficient than the uncoordinated ones, especially when coordinated planning uses systematic methods.


Assuntos
Organismos Aquáticos , Conservação dos Recursos Naturais/métodos , Fenômenos Ecológicos e Ambientais , Biologia Marinha/métodos , Ecossistema , Filipinas , Dinâmica Populacional
12.
Glob Chang Biol ; 21(1): 195-205, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25088977

RESUMO

Coral reefs and lagoons worldwide are vulnerable environments. However, specific geomorphological reef types (fringing, barrier, atoll, bank for the main ones) can be vulnerable to specific disturbances that will not affect most other reefs. This has implications for local management and science priorities. Several geomorphologically closed atolls of the Pacific Ocean have experienced in recent decades mass benthic and pelagic lagoonal life mortalities, likely triggered by unusually calm weather conditions lasting for several weeks. These events, although poorly known, reported, and characterized, pose a major threat for resource sustainability. Based on a sample of eleven events on eight atolls from the central South Pacific occurring between 1993 and 2012, the conservative environmental thresholds required to trigger such events are identified using sea surface temperature, significant wave height and wind stress satellite data. Using these thresholds, spatial maps of potential risk are produced for the central South Pacific region, with the highest risk zone lying north of Tuamotu Archipelago. A regional climate model, which risk map compares well with observations over the recent period (r=0.97), is then used to downscale the projected future climate. This allows us to estimate the potential change in risk by the end of the 21st century and highlights a relative risk increase of up to 60% for the eastern Tuamotu atolls. However, the small sample size used to train the analysis led to the identification of conservative thresholds that overestimated the observed risk. The results of this study suggest that long-term monitoring of the biophysical conditions of the lagoons at risk would enable more precise identification of the physical thresholds and better understanding of the biological processes involved in these rare, but consequential, mass mortality events.


Assuntos
Conservação dos Recursos Naturais , Recifes de Corais , Animais , Bivalves/fisiologia , Clima , Ecossistema , Peixes/fisiologia , Modelos Teóricos , Mortalidade , Ilhas do Pacífico , Oceano Pacífico , Temperatura Ambiente , Movimentos da Água , Poluição da Água/estatística & dados numéricos , Tempo (Meteorologia) , Vento
13.
Zootaxa ; 3832: 1-247, 2014 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-25081275

RESUMO

A checklist of the marine and estuarine fishes of Madang District is presented, combining both previous and new records. After the recent PAPUA NIUGINI 2012 expedition, a total of 1337 species in 129 families have been recorded from the region. One species and one family is not native (Cichlidae: Oreochromis mossambicus), but has been introduced. The native fish fauna of Madang therefore consists of 1336 species in 128 families. The largest families are the Gobiidae, Labridae, Pomacentridae, Apogonidae, Serranidae, Blenniidae, Chaetodontidae, Syngnathidae and Muraenidae, Scorpaenidae and Lutjanidae, Myctophidae, Acanthuridae, Scaridae, Holocentridae, Carangidae, Pomacanthidae and Tetraodontidae, and Caesionidae. A total of 820 fish species (61.4 % of the total marine and estuarine fish fauna) are recorded from Madang for the first time. The fish fauna of Madang includes a total of 187 species of transitional waters and 1326 species in marine habitats. A total of 156 species of the marine or estuarine species also occurs in freshwater. Zoogeographically, 1271 species have a wide distribution range, most frequently a broad Indo-West Pacific distribution. Among the remaining species, only 8 are endemic to Madang District. Anthropogenic threats to the fish fauna and habitats of Madang District include extensive fishing in Madang Lagoon, sometimes with destructive fishing practices; the discharge of untreated sewage of human settlements, mining and industrial developments into the lagoon and nearby oceanic habitats; and destruction of mangrove habitats by extensive construction work on the shores. These anthropogenic threats may call for conservation and monitoring measures in the near future.


Assuntos
Peixes/classificação , Distribuição Animal , Animais , Biodiversidade , Lista de Checagem , Ecossistema , Feminino , Masculino , Papua Nova Guiné
14.
PLoS One ; 9(5): e97409, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24835216

RESUMO

Numerous threats impact coral reefs and conservation actions are urgently needed. Fast production of marine habitat maps promotes the use of habitat-only conservation plans, where a given percentage of the area of each habitat is set as conservation objectives. However, marine reserves can impact access to fishing grounds and generate opportunity costs for fishers that need to be minimized. In New Caledonia (Southwest Pacific), we used fine-scale fishery catch maps to define nineteen opportunity costs layers (expressed as biomass catch loss) considering i) total catches, ii) target fish families, iii) local marine tenure, and iv) gear type. The expected lower impacts on fishery catch when using the different cost constraints were ranked according to effectiveness in decreasing the costs generated by the habitat-only scenarios. The exercise was done for two habitat maps with different thematic richness. In most cases, habitat conservation objectives remained achievable, but effectiveness varied widely between scenarios and between habitat maps. The results provide practical guidelines for coral reef conservation and management. Habitat-only scenarios can be used to initiate conservation projects with stakeholders but the costs induced by such scenarios can be lowered by up to 50-60% when detailed exhaustive fishery data are used. When using partial data, the gain would be only in the 15-25% range. The best compromises are achieved when using local data.


Assuntos
Conservação dos Recursos Naturais/métodos , Recifes de Corais , Ecossistema , Pesqueiros/economia , Pesqueiros/métodos , Peixes/fisiologia , Animais , Biomassa , Pesqueiros/estatística & dados numéricos , Modelos Econômicos , Nova Caledônia
15.
Mar Pollut Bull ; 83(1): 224-30, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24759510

RESUMO

Pearl oyster aquaculture is a major activity in French Polynesia atoll lagoons. After the economic decline that characterized the last decade, concerns recently rose about discarded installations and materials that supported aquaculture practices and by facilities abandoned after they had to close their activities. In May 2013, a first inventory of the type and amount of pearl farms derelict gear (PFDG) was achieved on 47 sites in Ahe lagoon. Surveys were conducted within and outside the boundaries of aquaculture concessions. Twenty types of PFDG littered the lagoon floor and the water column. The most impacted areas were near abandoned grafting houses with up to nine types of PFDG. Forty-five percent of the sites were impacted, including outside concessions. While management authorities are fully aware of the problem, this first assessment is a wake-up call to stimulate the cleaning of lagoons, enhance awareness among farmers, and identify potential ecological consequences on lagoon ecosystems.


Assuntos
Aquicultura , Resíduos Industriais/estatística & dados numéricos , Pinctada , Resíduos/estatística & dados numéricos , Animais , Polinésia
16.
PLoS One ; 9(4): e95050, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24740288

RESUMO

Studying the larval dispersal of bottom-dwelling species is necessary to understand their population dynamics and optimize their management. The black-lip pearl oyster (Pinctada margaritifera) is cultured extensively to produce black pearls, especially in French Polynesia's atoll lagoons. This aquaculture relies on spat collection, a process that can be optimized by understanding which factors influence larval dispersal. Here, we investigate the sensitivity of P. margaritifera larval dispersal kernel to both physical and biological factors in the lagoon of Ahe atoll. Specifically, using a validated 3D larval dispersal model, the variability of lagoon-scale connectivity is investigated against wind forcing, depth and location of larval release, destination location, vertical swimming behavior and pelagic larval duration (PLD) factors. The potential connectivity was spatially weighted according to both the natural and cultivated broodstock densities to provide a realistic view of connectivity. We found that the mean pattern of potential connectivity was driven by the southwest and northeast main barotropic circulation structures, with high retention levels in both. Destination locations, spawning sites and PLD were the main drivers of potential connectivity, explaining respectively 26%, 59% and 5% of the variance. Differences between potential and realistic connectivity showed the significant contribution of the pearl oyster broodstock location to its own dynamics. Realistic connectivity showed larger larval supply in the western destination locations, which are preferentially used by farmers for spat collection. In addition, larval supply in the same sectors was enhanced during summer wind conditions. These results provide new cues to understanding the dynamics of bottom-dwelling populations in atoll lagoons, and show how to take advantage of numerical models for pearl oyster management.


Assuntos
Aquicultura/métodos , Ecossistema , Modelos Biológicos , Pinctada/crescimento & desenvolvimento , Algoritmos , Animais , Geografia , Larva/crescimento & desenvolvimento , Polinésia , Dinâmica Populacional , Análise de Componente Principal , Estações do Ano , Água do Mar , Movimentos da Água , Vento
17.
Mar Pollut Bull ; 81(1): 191-9, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24559737

RESUMO

A gap analysis is the initial step towards the identification of areas where data are needed. However, often, data coverage cannot be assessed against a reference that objectively guides the identification of both gaps and priority areas for data acquisition. Here, we describe a quick, effective and reproducible spatial data gap analysis approach based on the relationship between location of available metadata and coral reef geomorphological richness. In Solomon Islands, we identified gaps defined by high richness and low biological data coverage. We collected metadata only, to avoid dealing with data ownership, availability, and formats, and to be able to identify gaps in less than two months. This fast method does not replace quantitative and comprehensive gap analysis, but provides effective identification of areas of high natural value and limited knowledge. The method is widely applicable and particularly invaluable for large and complex domains such as the Coral Triangle.


Assuntos
Recifes de Corais , Ecossistema , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Animais , Conservação dos Recursos Naturais , Ilhas do Pacífico , Fatores Socioeconômicos
18.
Curr Biol ; 24(5): 555-60, 2014 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-24560574

RESUMO

Beyond the loss of species richness, human activities may also deplete the breadth of evolutionary history (phylogenetic diversity) and the diversity of roles (functional diversity) carried out by species within communities, two overlooked components of biodiversity. Both are, however, essential to sustain ecosystem functioning and the associated provision of ecosystem services, particularly under fluctuating environmental conditions. We quantified the effect of human activities on the taxonomic, phylogenetic, and functional diversity of fish communities in coral reefs, while teasing apart the influence of biogeography and habitat along a gradient of human pressure across the Pacific Ocean. We detected nonlinear relationships with significant breaking points in the impact of human population density on phylogenetic and functional diversity of parrotfishes, at 25 and 15 inhabitants/km(2), respectively, while parrotfish species richness decreased linearly along the same population gradient. Over the whole range, species richness decreased by 11.7%, while phylogenetic and functional diversity dropped by 35.8% and 46.6%, respectively. Our results call for caution when using species richness as a benchmark for measuring the status of ecosystems since it appears to be less responsive to variation in human population densities than its phylogenetic and functional counterparts, potentially imperiling the functioning of coral reef ecosystems.


Assuntos
Recifes de Corais , Peixes , Filogenia , Animais , Biodiversidade , Ecossistema , Humanos , Oceano Pacífico , Densidade Demográfica
19.
Adv Mar Biol ; 66: 213-90, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24182902

RESUMO

The Coral Sea, located at the southwestern rim of the Pacific Ocean, is the only tropical marginal sea where human impacts remain relatively minor. Patterns and processes identified within the region have global relevance as a baseline for understanding impacts in more disturbed tropical locations. Despite 70 years of documented research, the Coral Sea has been relatively neglected, with a slower rate of increase in publications over the past 20 years than total marine research globally. We review current knowledge of the Coral Sea to provide an overview of regional geology, oceanography, ecology and fisheries. Interactions between physical features and biological assemblages influence ecological processes and the direction and strength of connectivity among Coral Sea ecosystems. To inform management effectively, we will need to fill some major knowledge gaps, including geographic gaps in sampling and a lack of integration of research themes, which hinder the understanding of most ecosystem processes.


Assuntos
Antozoários/fisiologia , Biodiversidade , Oceanos e Mares , Animais , Mudança Climática , Demografia , Cadeia Alimentar , Atividades Humanas , Humanos , Poluição da Água
20.
Mar Pollut Bull ; 77(1-2): 300-7, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24095047

RESUMO

Monitoring ecological variables is mandatory to detect abnormal changes in ecosystems. When the studied variables exceed predefined alert thresholds, management actions may be required. In the past, alert thresholds have been typically defined by expert judgments and descriptive statistics. Recently, approaches based on statistical power were also used. In New Caledonia, seagrass monitoring is a priority given their vulnerability to natural and anthropic disturbances. To define a suitable monitoring strategy and alert thresholds, we compared a Percentile Based Approach (PBA) and a sensitivity analysis of power (SAP). Both methods defined statistically relevant alert thresholds, but the SAP approach was more robust to spatial and temporal variability of seagrass cover. Moreover, this method characterized the sensitivity of threshold values to sampling efforts, a useful knowledge for managers.


Assuntos
Biodiversidade , Ecossistema , Monitoramento Ambiental , Animais , Organismos Aquáticos/classificação , Organismos Aquáticos/crescimento & desenvolvimento , Nova Caledônia
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