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401.
Mass coral bleaching events have occurred on a global scale throughout the worlds tropical oceans and can result in large-scale coral mortality and degradation of coral reef communities. Coral bleaching has often been attributed to periods of above normal seawater temperatures and/or calm conditions with high levels of ultraviolet radiation. Unusually high shallow-water temperature (>29°C) in Kaneohe Bay, Hawaii, USA, in late summer (20 August–9 September) and fall (1–7 October) of 1996 produced visible bleaching of two dominant corals, Porites compressa Dana, 1864 and Montipora verrucosa Dana, 1864. The present study examined chlorophyll a (chl a), total lipid concentrations, and lipid class composition in corals of both species in which the entire colony was non-bleached, moderately bleached, or bleached. Skeletal, host tissue, and algal symbiont 13C values were also measured in non-bleached and bleached colonies. In additional unevenly bleached colonies, paired samples were collected from bleached upper surfaces and non-bleached sides. Samples were collected on 20 November 1996 during the coral recovery phase, a time when seawater temperatures had been back to normal for over a month. Chl a levels were significantly lower in bleached colonies of both species compared with non-bleached specimens, and in bleached areas of unevenly bleached single colonies. Total lipid concentrations were significantly lower in bleached P. compressa compared with non-bleached colonies, whereas total lipid concentrations were the same in bleached and non-bleached M. verrucosa colonies. The proportion of triacylglycerols and wax esters was lower in bleached colonies of both species. Both bleached and non-bleached M. verrucosa had from ~17% to 35% of their lipids in the form of diacylglycerol, while this class was absent in P. compressa. 13C was not significantly different in the host tissue and algal symbiont fractions in non-bleached and bleached samples of either species. This suggests that the ratio of carbon acquired heterotrophically versus photosynthetically was the same regardless of condition. Skeletal 13C was significantly lower in bleached than in non-bleached corals. This is consistent with previous findings that lower rates of photosynthesis during bleaching results in lower skeletal 13C values. The two species in this study displayed different lipid class compositions and total lipid depletions following bleaching, suggesting that there is a difference in their metabolism of lipid reserves and/or in their temporal responses to bleaching and recovery.Communicated by J.P. Grassle, New Brunswick 相似文献
402.
Elena E. Andreeva Yuriy G. Mikhaylichenko Alexandre N. Vylegjanin 《Journal of Coastal Conservation》2003,9(1):19-24
Coastal area management should be considered as an element of a more general philosophy—that of natural resource management—which
is in the process of replacing the purely ‘protection of the environment’ approach which was dominated most of the 20th century.
Specific legislation on coastal management has been adopted by many countries, and today steps have been taken to acumulate
all experience accumulated and to harmonize legal regulations on the international level. For the Russian Federation, formerly
the Soviet Union, with an enormous sea-shore line to cope with, it is a new experience to develop a concept and a legal regulation
specifically tackling coastal area management. The draft of a legislative act on coastal area management reflects the attempts
to find ways for harmonizing various economic, environmental and social interests in this huge area, encompassing relevant
Russian legislation in force as well as international conventions and treaties, and taking into considerations and treatices,
and taking into consideration foregin expereience in this field. 相似文献
403.
404.
Noureddin Osseiran Manolis N. Romanias Vincent Gaudion Maria E. Angelaki Vassileios C. Papadimitriou Alexandre Tomas Patrice Coddeville Frederic Thevenet 《环境科学学报(英文版)》2020,32(9):141-154
Atmospheric simulation chambers, are unique tools for investigating atmospheric processes in the gas and heterogeneous phases. They can provide a controlled yet realistic environment that simulates atmospheric conditions. In the current study, a Teflon atmospheric simulation chamber of 600 L, named THALAMOS (thermally regulated atmospheric simulation chamber) has been developed and cross-validated. THALAMOS can be operated over the temperature range 233 to 373 K under both static and flow conditions. It is equipped with state of the art instrumentation (selective ion flow tube mass spectrometry (SIFT-MS), long path Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS), various analyzers) for the in-line monitoring of both reactants and products. THALAMOS was validated by measuring the rate coefficients of well documented reactions, i.e. the reaction of ethanol with OH radicals and the reaction of dichloromethane with Cl atoms, in a wide temperature range. Two different detection techniques were used in parallel, FTIR and SIFT-MS, to internally cross-validate the obtained results. The measured rate coefficients are in excellent agreement, both between each other and with the literature recommended values. Furthermore, the gas phase oxidation of toluene by Cl atoms (kinetics and product yields) was studied in the temperature range of 253 to 333 K. To the best of our knowledge, THALAMOS is a unique facility on national level and among a few smog chambers internationally that can be operated in such a wide temperature range providing the scientific community with a versatile tool to simulate both outdoor and indoor physicochemical processes. 相似文献
405.
Janaína Campos Senra Carlos Tadashi Yoshizaki Giovana Farina Doro Rodrigo Ruano Maria Augusta Bento Cicaroni Gibelli Agatha Sacramento Rodrigues Vera Hermina Kalika Koch Vera Lúcia Jornada Krebs Marcelo Zugaib Rossana Pulcineli Vieira Francisco Lisandra Stein Bernardes 《黑龙江环境通报》2020,40(11):1408-1417
406.
Dielle Monteiro Teixeira Juliana Merces Hernandez Luciana Damascena Silva Darleise de Souza Oliveira Paula Katharine de Pontes Spada Tereza Cristina Monteiro Gurjão Joana D’Arc Pereira Mascarenhas Alexandre Costa Linhares Lena Líllian Canto de Sá Morais Yvone Benchimol Gabbay 《Food and environmental virology》2016,8(1):101-104
Noroviruses are the major cause of non-bacterial acute gastroenteritis outbreaks in humans, with few reports about the occurrence of the norovirus GIV strain. We investigated the presence of norovirus GIV in surface water (river, bay, and stream) and untreated sewage, and we determined a positivity rate of 9.4 % (9/96). The strains genotyped were GIV.1. To our knowledge, this is the first report of GIV in Brazil. 相似文献
407.
Pascaline Le Gouar Alexandre Robert Jean-Pierre Choisy Sylvain Henriquet Philippe Lecuyer Christian Tessier Fran?ois Sarrazin 《Ecological applications》2008,18(4):859-872
The success of reintroduction programs greatly depends on the amount of mortality and dispersal of the released individuals. Although local environmental pressures are likely to play an important role in these processes, they have rarely been investigated because of the lack of spatial replicates of reintroduction. In the present study, we analyzed a 25-year data set encompassing 272 individuals released in five reintroduction programs of Griffon Vultures (Gyps fulvus) in France to examine the respective roles of survival and dispersal in program successes and failures. We use recent developments in multi-strata capture-recapture models to take into account tag loss in survival estimates and to consider and estimate dispersal among release areas. We also examined the effects of sex, age, time, area, and release status on survival, and we tested whether dispersal patterns among release areas were consistent with habitat selection theories. Results indicated that the survival of released adults was reduced during the first year after release, with no difference between sexes. Taking into account local observations only, we found that early survival rates varied across sites. However when we distinguished dispersal from mortality, early survival rates became equal across release sites. It thus appears that among reintroduction programs difference in failure and success was due to differential dispersal among release sites. We revealed asymmetrical patterns of dispersal due to conspecific attraction: dispersers selected the closest and the largest population. We showed that mortality can be homogeneous from one program to another while, on the contrary, dispersal is highly dependent on the matrix of established populations. Dispersal behavior is thus of major interest for metapopulation restoration and should be taken into account in planning reintroduction designs. 相似文献
408.
Kathryn Falb Betsy Laird Ruwan Ratnayake Katherine Rodrigues Jeannie Annan 《Disasters》2019,43(4):711-726
The number of research studies in the humanitarian field is rising. It is imperative, therefore, that institutional review boards (IRBs) consider carefully the additional risks present in crisis contexts to ensure that the highest ethical standards are upheld. Ethical guidelines should represent better the specific issues inherent to research among populations grappling with armed conflict, disasters triggered by natural hazards, or health‐related emergencies. This paper seeks to describe five issues particular to humanitarian settings that IRBs should deliberate and on which they should provide recommendations to overcome associated challenges: staged reviews of protocols in acute emergencies; flexible reviews of modification requests; addressing violence and the traumatic experiences of participants; difficulties in attaining meaningful informed consent among populations dependent on aid; and ensuring reviews are knowledgeable of populations' needs. Considering these matters when reviewing protocols will yield more ethically sound research in humanitarian settings and hold researchers accountable to appropriate ethical standards. 相似文献
409.
410.
In the context of coastal management the aim of this paper is to present the development of a fuzzy model through the application of a Genetic algorithm in order to select the most appropriate set of variables and improve our understanding with a set of rules. The case studied is the chlorophyll response as bioindicator of ecological status in the Northeast coastal upwelling system of Rio de Janeiro state, Southeastern of Brazil. The prediction of the fuzzy model has shown an improved performance when compared to the traditional approaches as Multiple Regression modelling. The results show that the set of inferred rules can assess three different water masses. Despite the increased occurrence of upwelling is observed in spring–summer period and some instability of the model, it is able to forecast some chlorophyll peaks. We conclude that the sampling frequency is crucial to reach a better performance. 相似文献