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1.
Słodczyk Elżbieta Pietranik Anna Glynn Sarah Wiedenbeck Michael Breitkreuz Christoph Dhuime Bruno 《International Journal of Earth Sciences》2018,107(6):2065-2081
International Journal of Earth Sciences - The Polish Lowlands, located southwest of the Teisseyre–Tornquist Zone, within Trans-European Suture Zone, were affected by bimodal, but dominantly... 相似文献
2.
J. E. Glynn P. W. Glynn 《Stochastic Environmental Research and Risk Assessment (SERRA)》1996,10(1):17-37
A diffusion approximation for a network of continuous time reservoirs with power law release rules is examined. Under a mild assumption on the inflow processes, we show that for physically reasonable values of the power law constants, the system of processes converges to a multi-dimensional Gaussian diffusion process. We also illustrate how the limiting Gaussian process may be used to compute approximations to the original system of reservoirs. In addition, we study the quality of our approximations by comparing them to results obtained by simulations of the original watershed model. The simulations offer support for the use of the approximation developed here. 相似文献
3.
Climate change and coral reef bleaching: An ecological assessment of long-term impacts,recovery trends and future outlook 总被引：2，自引：0，他引：2
Since the early 1980s, episodes of coral reef bleaching and mortality, due primarily to climate-induced ocean warming, have occurred almost annually in one or more of the world's tropical or subtropical seas. Bleaching is episodic, with the most severe events typically accompanying coupled ocean–atmosphere phenomena, such as the El Niño-Southern Oscillation (ENSO), which result in sustained regional elevations of ocean temperature. Using this extended dataset (25+ years), we review the short- and long-term ecological impacts of coral bleaching on reef ecosystems, and quantitatively synthesize recovery data worldwide. Bleaching episodes have resulted in catastrophic loss of coral cover in some locations, and have changed coral community structure in many others, with a potentially critical influence on the maintenance of biodiversity in the marine tropics. Bleaching has also set the stage for other declines in reef health, such as increases in coral diseases, the breakdown of reef framework by bioeroders, and the loss of critical habitat for associated reef fishes and other biota. Secondary ecological effects, such as the concentration of predators on remnant surviving coral populations, have also accelerated the pace of decline in some areas. Although bleaching severity and recovery have been variable across all spatial scales, some reefs have experienced relatively rapid recovery from severe bleaching impacts. There has been a significant overall recovery of coral cover in the Indian Ocean, where many reefs were devastated by a single large bleaching event in 1998. In contrast, coral cover on western Atlantic reefs has generally continued to decline in response to multiple smaller bleaching events and a diverse set of chronic secondary stressors. No clear trends are apparent in the eastern Pacific, the central-southern-western Pacific or the Arabian Gulf, where some reefs are recovering and others are not. The majority of survivors and new recruits on regenerating and recovering coral reefs have originated from broadcast spawning taxa with a potential for asexual growth, relatively long distance dispersal, successful settlement, rapid growth and a capacity for framework construction. Whether or not affected reefs can continue to function as before will depend on: (1) how much coral cover is lost, and which species are locally extirpated; (2) the ability of remnant and recovering coral communities to adapt or acclimatize to higher temperatures and other climatic factors such as reductions in aragonite saturation state; (3) the changing balance between reef accumulation and bioerosion; and (4) our ability to maintain ecosystem resilience by restoring healthy levels of herbivory, macroalgal cover, and coral recruitment. Bleaching disturbances are likely to become a chronic stress in many reef areas in the coming decades, and coral communities, if they cannot recover quickly enough, are likely to be reduced to their most hardy or adaptable constituents. Some degraded reefs may already be approaching this ecological asymptote, although to date there have not been any global extinctions of individual coral species as a result of bleaching events. Since human populations inhabiting tropical coastal areas derive great value from coral reefs, the degradation of these ecosystems as a result of coral bleaching and its associated impacts is of considerable societal, as well as biological concern. Coral reef conservation strategies now recognize climate change as a principal threat, and are engaged in efforts to allocate conservation activity according to geographic-, taxonomic-, and habitat-specific priorities to maximize coral reef survival. Efforts to forecast and monitor bleaching, involving both remote sensed observations and coupled ocean–atmosphere climate models, are also underway. In addition to these efforts, attempts to minimize and mitigate bleaching impacts on reefs are immediately required. If significant reductions in greenhouse gas emissions can be achieved within the next two to three decades, maximizing coral survivorship during this time may be critical to ensuring healthy reefs can recover in the long term. 相似文献
4.
Regional and species specific sexual reproductive patterns of three zooxanthellate scleractinian corals across the Eastern Tropical Pacific 
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下载免费PDF全文 Jeimy D. Santiago‐Valentín Susan B. Colley Peter W. Glynn Amilcar L. Cupul‐Magaña Ramon A. López‐Pérez Fabián A. Rodríguez‐Zaragoza Francisco Benítez‐Villalobos Eric Bautista‐Guerrero Denisse A. Zavala‐Casas Alma P. Rodríguez‐Troncoso 《Marine Ecology》2018,39(2)
Sexual reproduction of zooxanthellate scleractinian corals in the Eastern Tropical Pacific (ETP) is influenced by the interactive effects of regional and local oceanographic conditions, as well as a variety of other environmental factors. Differences in spatial and temporal gamete development and reproductive patterns of three widespread scleractinian corals of this region—Pocillopora damicornis (branching colony morphology, characterized as hermaphrodite broadcaster), Pavona gigantea (massive colonies, characterized as gonochoric broadcaster/sequential co‐sexually hermaphroditic) and Porites panamensis (encrusting colonies, characterized as gonochoric brooder)—were evaluated at local and regional scales across the ETP. This area extended from the Gulf of California (24°N) to the southern coast of Ecuador (–1°S), including offshore islands, using existing data pooled from prior studies. Predictive models were employed based on environmental variables: sea surface temperature, daylight hours, diffuse attenuation co‐efficient at 490 nm and photosynthetically active radiation. Datasets were extracted from satellite images ( https://oceancolor.gsfc.nasa.gov ) and analysed using WAM_STATIST ver. 6.33® software to obtain monthly average data from each site. The spatial (region, sub‐region and site) and seasonal (wet, dry) variation in reproductive activity (% colonies with gametes) differed among the three species; significant interactions were season × sub‐region for P. damicornis, season × site (sub‐region) for P. gigantea, and season × site for P. panamensis, for which sub‐region was not considered as a factor. The predictive models also suggest that gamete production/maturation of P. damicornis and P. gigantea is influenced by local differences in sea surface temperature and daylight hours. Porites panamensis was not correlated with any environmental variable examined. Variations in local and regional reproductive developmental patterns are likely an acclimatization response by each species imposed by the timing and duration of local stressor events. This analysis has provided insights into the diverse local and regional physical drivers that affect species responses and acclimatization in sexual reproduction across the ETP. 相似文献
5.
McHugh B Law RJ Allchin CR Rogan E Murphy S Foley MB Glynn D McGovern E 《Marine pollution bulletin》2007,54(11):1724-1731
Concentrations and enantiomeric profiles for a range of organochlorine compounds are reported in blubber samples from a number of individual killer whales (Orcinus orca) from British and Irish waters. Elevated contaminant levels and enriched isotopic ratios were determined in one individual whale sampled in the Scottish Western Isles compared to the others suggesting marine mammal based dietary influences. The potential application of isotopic ratios to model contaminant uptake, enantioselective enrichment and accumulation is demonstrated. Data are presented which provide information on enantioselective enrichment factors (EFs) for o,p'-DDT, alpha-HCH and toxaphene congeners CHB26 and CHB 50. This dataset further improves the current database on reported levels of a number of contaminants and provides additional background information on potential metabolic processes in killer whales from British and Irish waters. 相似文献
6.
Herbicide residues including 2,4-D and 2,4,5-T have been detected in the tissues of corals subject to massive mortality in the Gulf of Chiriquí, Panamá. Tolerance tests conducted using Pocillopora damicornis demonstrated a toxic effect of a commercial herbicide (incorporating 2,4-D) on this coral. 相似文献
7.
Cristian Mattar Andrés Santamaría-Artigas Flavio Ponzoni Cibele T. Pinto Carolina Barrientos Glynn Hulley 《International Journal of Digital Earth》2019,12(1):43-61
This work presents the preliminary results of the first field calibration campaign performed in the Atacama Desert, Chile, between the 18 and 22 August 2014, called the Atacama Field Campaign (ATAFIC 2014). In situ measurements were performed in order to spectrally characterize the surface reflectance spectra between 0.3 and 2.5?µm, radiometric temperature (8.0–14.0?µm) and atmospheric measurements. A soil sample was collected and analyzed using Fourier Transform Infrared Spectroscopy and X-Ray Diffraction techniques to characterize the surface reflectance spectra and mineralogical composition, respectively. ASTER land surface emissivity in addition to GOES, MODIS and Landsat-8 land surface temperature (LST) were also used. Results showed that the spectral features of the Atacama soil and the characteristics of this geographical zone, which is featured as the most hyper-arid and cloudless place in the world, make this area a potential target for surface reflectance characterization. Day and night LST comparison between field and remote sensing data are lower than 2?K and the Root Mean Square Error for land surface emissivity is close to 2%. This work opens the possibilities to consider the Atacama Desert as a reference target for calibration and validation activities for earth observation missions’ purposes. 相似文献
8.
Despite the broad impact and importance of saltwater intrusion in coastal aquifers, little research has been directed towards forecasting saltwater intrusion in areas where the source of saltwater is uncertain. Saline contamination in inland groundwater supplies is a concern for numerous communities in the southern US including the city of Deltona, Florida. Furthermore, conventional numerical tools for forecasting saltwater contamination are heavily dependent on reliable characterization of the physical characteristics of underlying aquifers, information that is often absent or challenging to obtain. To overcome these limitations, a reliable alternative data-driven model for forecasting salinity in a groundwater supply was developed for Deltona using the fast orthogonal search (FOS) method. FOS was applied on monthly water-demand data and corresponding chloride concentrations at water supply wells. Groundwater salinity measurements from Deltona water supply wells were applied to evaluate the forecasting capability and accuracy of the FOS model. Accurate and reliable groundwater salinity forecasting is necessary to support effective and sustainable coastal-water resource planning and management. The available (27) water supply wells for Deltona were randomly split into three test groups for the purposes of FOS model development and performance assessment. Based on four performance indices (RMSE, RSR, NSEC, and R), the FOS model proved to be a reliable and robust forecaster of groundwater salinity. FOS is relatively inexpensive to apply, is not based on rigorous physical characterization of the water supply aquifer, and yields reliable estimates of groundwater salinity in active water supply wells. 相似文献
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10.
Peter W. Glynn Robert H. Stewart John E. McCosker 《International Journal of Earth Sciences》1972,61(2):483-519
Structural coral reefs of Recent age are undergoing vigorous growth on the eastern Pacific continental shores of Panamá. Coelenterate hermatypes include 20 species; 3 are hydrocorals in the genusMillepora, a notable new record for the eastern Pacific region; the abundant scleractinians arePocillopora (4 spp.),Pavona (6 spp.) andPorites (5 spp.).Pocillopora is the chief constructor of mound and fringing reefs with massivePavona andPorites sometimes important at the reef base. UninterruptedPocillopora growth characterizes some fringing reefs, forming a vertical framework with observed maximum thickness of 6 m. Binding of coral by encrusting coralline algae imparts a more rigid and coherent structure to the reef crest and peripheral faces. Intra-reef and flanking sediments contain over 90% calcareous matter; the predominant grain constituents arePocillopora, cirriped and mollusk fragments. Reefs attain their greatest development in the Gulf of Chiriquí; the reason for this is sought in the high and stable thermal conditions of this area. Radiometric dating indicates that net vertical reef growth may approach 1 m/250 years or 4000 B.Important coral predators include fishes, a gastropod, paguran decapods andAcanthaster (in certain areas). Quantitative measurements of the feeding rates and population densities of corallivores indicate that predators may destroy approximately one-third of the annual growth of aPocillopora coral community.
Zusammenfassung Die rezenten Korallenriffstrukturen an der östlichen Pazifikküste von Panamá zeigen starkes Wachstum. Von den 20 vorhandenen Arten hermatypischer Coelenteraten gehören 3 zu der GattungMillepora, die erstmals im ostpazifischen Raum beobachtet wurde. Die häufigeren Scleractinia sindPocillopora (4 Arten),Pavona (6 Arten) undPorites (5 Arten).Pocillopora ist der wichtigste Gerüstbildner in Kuppen- und Saumriffen, während die massigen Kolonien vonPavona undPorites an der Basis der Riffe wichtig werden können. Für einige Saumriffe ist ununterbrochenesPocillopora-Wachstum charakteristisch, das zum Bau eines vertikalen Gerüstes von maximal 6 m Höhe führt. Der Verbund von Korallen durch inkrustierende koralline Algen gibt der Struktur an Ober- und Außenseiten Festigkeit und Zusammenhalt. Die Sedimente innerhalb und außerhalb der Riffstrukturen bestehen zu 90% aus Karbonaten; die häufigsten Komponenten sind Bruchstücke vonPocillopora, Cirrepediern und Mollusken. Die Riffentwicklung erreicht ihren Höhepunkt im Golf von Chiriquí, vermutlich weil in diesem Gebiet die Temperaturen hoch und gleichmäßig sind. Radiometrische Altersbestimmungen haben ein Vertikalwachstum von 1 m/250 Jahre oder 4000 Bubnoff-Einheiten ergeben.Fische, ein Gastropode und Dekapoden (Paguren) sowie — in bestimmten Gegenden-Acanthaster sind wichtige Gegner der Korallen. Quantitative Erfassung von Nahrungsmengen und Bevölkerungsdichten der Corallivoren ergab, daß diese etwa ein Drittel des jährlichen Zuwachses vonPocillopora zerstören.
Résumé Les récifs structuraux récents de coraux de la côte Panamienne du Pacifique orientale présentent une croissance importante. Pour la première fois it fut possible d'observer dans le Pacifique orientale, parmi les 20 espèces de Coelentérés hermatypiques, 3 espèces appartenant au gènreMillepora. Les Scleractinia les plus fréquents sont lesPocillopora (4 espèces), lesPavona (6 espèces) et lesPorites (5 espèces). LesPocillopora sont l'élément le plus important de charpente des pitons sous-marins et des récifs frangeants, tandis que des colonies massives dePavona et dePorites sont parfois importantes à la base des récifs. La caractéristique des récifs frangeants est en partie représentée par la croissance ininterrompue dePocillopora conduisant à la construction d'une charpente verticale d'une hauteur maximale de 6 m. Une liaison des coraux par des algues corallines crouteuses forme une structure plus forte et cohérente du sommet et du peripherie des récifs. Les sédiments structuraux interieurs et exterieurs des récifs sont constitués à 90% par des carbonates. Les composants les plus fréquents sont des fragments dePocillopora, de cirripèdes et de mollusques. Le dévelopement du récif atteint sont maximum dans le golfe du Chiriquí. La cause est cherchée dans les températures élevées et stables de cette région. Des précisions radiométriques sur l'âge donnent, pour la croissance verticale, une hauteur d'un mètre pour 250 années ou 4000 unités Bubnoff.Des poissons, un gastéropode, des décapodes (pagures) ainsi que — dans quelques endroits - desAcanthaster sont des ennemis importants des coraux. Des récensements quantitatifs du nourriture et de la densite des populations des corallivores démontrent qu'ils détruisent a peu près un tiers de l'accroissement annuel desPocillopora.
( ) . 20 , 3 ill, . Scleractinia, : Pocillopora 4 , Pavona 6 Porites 5 . Pocillopora , , Pavona Porites. Pocillopora, 6 . - 90%. . Pocillopora, Cirrepedier, . Chiriqui. , 1 250 . (, , , Acanthaster). , 1/3 Pocillopora.相似文献