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Resting Stages of Plankton in Recent North Adriatic Sediments 总被引:6,自引:0,他引:6
Fernando Rubino Genuario Belmonte Anna M. Miglietta Sebastiano Geraci & Ferdinando Boero 《Marine Ecology》2000,21(3-4):263-284
Abstract. Plankton-derived resting stages were found in 26 sediment cores collected in the North Adriatic Sea; 46 morphotypes were identified, 38 were attributed to taxa according to their morphology and, in some hatching cases, also according to the morphology of the derived active forms. Six species of Dinophyta were recorded for the first time from the North Adriatic Sea. Each morphotype was described in detail. Twenty-nine resting stages were Dinophyta; one was a Chrysophyta; two were Tintinnina; and six were metazoans. At every site Dinophyta cysts were more abundant than Metazoa cysts. Cyst bank densities were variable, with empty forms generally more abundant than full ones; cyst concentrations were highest at the mouth of the Po River delta. 相似文献
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Giuseppe?Roberto?Tomasicchio Letizia?Lusito Felice?D’AlessandroEmail author Ferdinando?Frega Antonio?Francone Samuele?De?Bartolo 《Stochastic Environmental Research and Risk Assessment (SERRA)》2018,32(12):3397-3408
The estimation of long-term sea level variability is of primary importance for a climate change assessment. Despite the value of the subject, no scientific consensus has yet been reached on the existing acceleration in observed values. The existence of this acceleration is crucial for coastal protection planning purposes. The absence of the acceleration would enhance the debate on the general validity of current future projections. Methodologically, the evaluation of the acceleration is a controversial and still open discussion, reported in a number of review articles, which illustrate the state-of-art in the field of sea level research. In the present paper, the well-proven direct scaling analysis approach is proposed in order to describe the long-term sea level variability at 12 worldwide-selected tide gauge stations. For each of the stations, it has been shown that the long-term sea level variability exhibits a trimodal scaling behaviour, which can be modelled by a power law with three different pairs of shape and scale parameters. Compared to alternative methods in literature, which take into account multiple correlated factors, this simple method allows to reduce the uncertainties on the sea level rise parameters estimation. 相似文献
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Acta Geotechnica - Structured granular materials exhibit strongly anisotropic mechanical behaviours resulting from the directional properties of their microstructural components such as grain... 相似文献
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Acta Geotechnica - In the original publication, the first name of the authors was exchanged with the last name inadvertently. The name of the authors should be as below. 相似文献
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Ferdinando Bosi Henrik Skogby Tonči Balić-Žunić 《Physics and Chemistry of Minerals》2016,43(6):395-407
A dravite from Yemen of near end-member composition was treated in air and hydrogen atmospheres at 600–900 °C to reveal changes in Mg and Al order over the octahedrally coordinated Y and Z sites, and to explore related changes in the characteristic vibrational bands in the principal (OH)-stretching frequency. Relevant information was obtained using electron microprobe analysis (EMPA), structural refinement (SREF) and polarized infrared (IR) single-crystal spectroscopy. Overall, the EMPA, SREF and IR data show that only minor changes occur during thermal treatment up to at least 800 °C, including variations in structural parameters, Mg–Al order–disorder and (OH)-stretching bands, indicating limited hydrogen loss. Untreated and treated dravite samples have very similar long-range and short-range atomic structures, which may be related to the occurrence of stable Al–Mg extended clusters around the O1 (=W) and O3 (=V) sites: W(F)–Y(MgMgMg)–V(OH)3–Z[AlAlAlAlAl(Al,Mg)]; W(OH)–Y(MgMgAl)–V(OH)3–Z[AlAlAlAlAl(Al,Mg)]; W(O2–)–Y(AlAlAl)–V(OH)3–Z[AlAlAlAlAl(Al,Mg)]. These extended clusters remain stable to temperatures close to the observed start of decomposition (~900 °C). 相似文献
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Abstract. An episodic event can be one of the many "episodes" forming a normal flow of related events. But it can also be an "incident" interrupting a trend and initiating a new one. Appreciation of contrasting meanings of apparently identical categories of phenomena is familiar to evolutionary biologists who, for instance, envisage evolution as the result of both gradual and punctuated events. Seasonal plankton blooms (both normal and noxious), species outbreaks, mass mortalities, and human predation are taken as examples of "episodes" that can influence and/or modify what we perceive as "normality". Recruitment is another example of an episodic event heavily conditioning both community structure and function, as recently highlighted by the so-called supply-side ecology. The reductionistic study of ecology. more linked to thermodynamics than to history, allowed the formulation of general ecological laws which, however, stem from the laws of thermodynamics. The totalizing value of such laws blurs appreciation of heterogeneity and change, so that many ecologists tend to be rather conservative, using a concept like "conservation" as an absolute paradigm to follow and to consider "change" as an a priori negative phenomenon. Episodes can have a "conservative" or "innovative" meaning, and are the driving force of the history of life. Their importance is recognized mainly when dealing with the history of organisms (evolutionary biology), whereas the assemblages of organisms ( i.e ., communities) are too often described and interpreted in an ahistorical context or in a too narrow time frame. Recognition of the importance of history in ecology (evolutionary ecology) can lead to a better understanding of environmental dynamics, albeit restricting the supposed predictive strength of ecology, a science timely integrating the reductionistic-thermodynamic approach with the holistic-historical one. 相似文献
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Caruso G Denaro MG Caruso R Mancari F Genovese L Maricchiolo G 《Marine environmental research》2011,72(1-2):46-52
Growth, haematological (haematocrit), biochemical (serum cortisol and glucose), and non-specific immune (lysozyme, serum haemolytic and haemagglutinating activities, extracellular respiratory burst activity) parameters, were monitored in European sea bass Dicentrarchus labrax and blackspot sea bream Pagellus bogaraveo subjected to a 31 days starvation compared to fed fish, to assess the responses to feed deprivation of these health status indicators. While haematocrit, serum cortisol, glucose and haemolytic activity of both species did not undergo significant variation following starvation, probably due to the short period applied, some non-specific immune parameters were affected significantly. In the starved sea bass, mucus lysozyme content doubled (1.8 U/mL) compared to the initial value. Haemagglutinating activity was significantly lower in starved sea bass than in fed fish after 31 days. In blackspot sea bream, a slight, not significant, reduction in haemagglutinating activity occurred 11 days after starvation. Respiratory burst activity decreased significantly in the starved fish. In spite of the limited number of examined parameters, the opportunity to use a panel of several indicators to obtain a more complete picture of health status in fish was underlined. 相似文献