scholarly journals The Role of Iron in the P-Acquisition Mechanisms of the Unicellular N2-Fixing Cyanobacteria Halothece sp., Found in Association with the Mediterranean Seagrass Posidonia oceanica

2020 ◽  
Author(s):  
Víctor Fernández-Juárez ◽  
Antoni Bennasar-Figueras ◽  
Antonio Tovar-Sanchez ◽  
Nona Sheila R Agawin
Keyword(s):  
Posidonia Oceanica ◽  
P Acquisition ◽  
The Mediterranean

scholarly journals The role of the seagrass <i>Posidonia oceanica</i> in the cycling of trace elements

2012 ◽  
Vol 9 (3) ◽  
pp. 2623-2653 ◽  
Author(s):  
C. Sanz-Lázaro ◽  
P. Malea ◽  
E. T. Apostolaki ◽  
I. Kalantzi ◽  
A. Marín ◽  
...  
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Posidonia Oceanica ◽  
Trophic Levels ◽  
Toxic Trace Elements ◽  
Relevant Role ◽  
Potentially Toxic Trace Elements ◽  
The Mediterranean ◽  
Element Transfer

Abstract. The aim of this work was to study the role of the seagrass Posidonia oceanica on the cycling of a wide set of trace elements (Ag, As, Ba, Bi, Cd, Co, Cr, Cs, Cu, Fe, Ga, Li, Mn, Ni, Pb, Rb, Sr, Tl, V and Zn). We measured the concentration of these trace elements in the different compartments of P. oceanica (leaves, rhizomes, roots and epibiota) in a non-polluted seagrass meadow representative of the Mediterranean and calculated the annual budget from a mass balance. We provide novel data on accumulation dynamics of many trace elements in P. oceanica compartments and demonstrate that trace element accumulation patterns are mainly determined by plant compartment rather than by temporal variability. Epibiota was the compartment which showed the greatest concentrations for most trace elements. Thus, they constitute a key compartment when estimating trace element transfer to higher trophic levels by P. oceanica. For most trace elements, translocation seemed to be low and acropetal. Zn, Cd, Sr and Rb were the trace elements that showed the highest release rate through decomposition of plant detritus, while Cs, Tl and Bi the lowest. P. oceanica acts as a sink of potentially toxic trace elements (Ni, Cr, As and Ag), which can be sequestered, decreasing their bioavailability. P. oceanica may have a relevant role in the cycling of trace elements in the Mediterranean.

scholarly journals The role of the seagrass <i>Posidonia oceanica</i> in the cycling of trace elements

2012 ◽  
Vol 9 (7) ◽  
pp. 2497-2507 ◽  
Author(s):  
C. Sanz-Lázaro ◽  
P. Malea ◽  
E. T. Apostolaki ◽  
I. Kalantzi ◽  
A. Marín ◽  
...  
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Posidonia Oceanica ◽  
Trophic Levels ◽  
Toxic Trace Elements ◽  
Relevant Role ◽  
Potentially Toxic Trace Elements ◽  
The Mediterranean ◽  
Element Transfer

Abstract. The aim of this study was to investigate the role of the seagrass Posidonia oceanica on the cycling of a wide set of trace elements (Ag, As, Ba, Bi, Cd, Co, Cr, Cs, Cu, Fe, Ga, Li, Mn, Ni, Pb, Rb, Sr, Tl, V and Zn). We measured the concentration of these trace elements in different compartments of P. oceanica (leaves, rhizomes, roots and epiphytes) in a non-polluted seagrass meadow representative of the Mediterranean and calculated the annual budget from a mass balance. We provide novel data on accumulation dynamics of many trace elements in P. oceanica compartments and demonstrate that trace element accumulation patterns are mainly determined by plant compartment rather than by temporal variability. Epiphytes were the compartment, which showed the greatest concentrations for most trace elements. Thus, they constitute a key compartment when estimating trace element transfer to higher trophic levels by P. oceanica. Trace element translocation in P. oceanica seemed to be low and acropetal in most cases. Zn, Cd, Sr and Rb were the trace elements that showed the highest release rate through decomposition of plant detritus, while Cs, Tl and Bi showed the lowest. P. oceanica acts as a sink of potentially toxic trace elements (Ni, Cr, As and Ag), which can be sequestered, decreasing their bioavailability. P. oceanica may have a relevant role in the cycling of trace elements in the Mediterranean.

Crossing the Pomerium

2020 ◽  
Author(s):  
Michael Koortbojian
Keyword(s):  
Social Practices ◽  
Civic Life ◽  
Public Monuments ◽  
Religion And Law ◽  
Mediterranean World ◽  
The Mediterranean ◽  
The Military ◽  
The City

The ancient Romans famously distinguished between civic life in Rome and military matters outside the city—a division marked by the pomerium, an abstract religious and legal boundary that was central to the myth of the city's foundation. This book explores, by means of images and texts, how the Romans used social practices and public monuments to assert their capital's distinction from its growing empire, to delimit the proper realms of religion and law from those of war and conquest, and to establish and disseminate so many fundamental Roman institutions across three centuries of imperial rule. The book probes such topics as the appearance in the city of Romans in armor, whether in representation or in life, the role of religious rites on the battlefield, and the military image of Constantine on the arch built in his name. Throughout, the book reveals how, in these instances and others, the ancient ideology of crossing the pomerium reflects the efforts of Romans not only to live up to the ideals they had inherited, but also to reconceive their past and to validate contemporary practices during a time when Rome enjoyed growing dominance in the Mediterranean world. The book explores a problem faced by generations of Romans—how to leave and return to hallowed city ground in the course of building an empire.

The formation of the Egyptian Arabic dialect area

2018 ◽  
Author(s):  
Peter Behnstedt ◽  
Manfred Woidich
Keyword(s):  
Mediterranean Coast ◽  
External Factors ◽  
Internal Factors ◽  
Dialect Contact ◽  
Historical Information ◽  
Egyptian Arabic ◽  
Transitional Area ◽  
The Mediterranean

This chapter deals with the sedentary dialects of Egypt, excluding the bedouin dialects of Sinai and the Libyan bedouin dialects on the Mediterranean coast. It attempts to combine historical information on the settlement of Arabic tribes in Egypt with accounts of present-day Egyptian dialects and those of the regions from which those tribes came, initially Yemen and the Levant, later Hejaz, and then the Maghreb. The diversity of the Egyptian Arabic dialect area is partly explained by external factors, namely different layers of arabization over centuries. It is also explained by internal factors, namely dialect contact, which implies phenomena such as hyperdialectisms. Egypt is seen as a dialect area in its own right, but one that shows phenomena of a transitional area between the Arab East and West. A case study of Alexandria deals with dialect death. The role of substrata is discussed, but is considered negligible.

scholarly journals Richness of Rhizosphere Organisms Affects Plant P Nutrition According to P Source and Mobility

Agriculture ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 157
Author(s):  
Jean Trap ◽  
Patricia Mahafaka Ranoarisoa ◽  
Usman Irshad ◽  
Claude Plassard
Keyword(s):  
Careful Consideration ◽  
Soil Conditions ◽  
Organic P ◽  
P Nutrition ◽  
Soil P ◽  
P Acquisition ◽  
Complex Interactions ◽  
Experimental Trials ◽  
The Relationship

Plants evolve complex interactions with diverse soil mutualist organisms to enhance P mobilization from the soil. These strategies are particularly important when P is poorly available. It is still unclear how the soil P source (e.g., mineral P versus recalcitrant organic P) and its mobility in the soil (high or low) affect soil mutualist biological (ectomycorrhizal fungi, bacteria and bacterial-feeding nematodes) richness—plant P acquisition relationships. Using a set of six microcosm experiments conducted in growth chamber across contrasting P situations, we tested the hypothesis that the relationship between the increasing addition of soil mutualist organisms in the rhizosphere of the plant and plant P acquisition depends on P source and mobility. The highest correlation (R2 = 0.70) between plant P acquisition with soil rhizosphere biological richness was found in a high P-sorbing soil amended with an organic P source. In the five other situations, the relationships became significant either in soil conditions, with or without mineral P addition, or when the P source was supplied as organic P in the absence of soil, although with a low correlation coefficient (0.09 < R2 < 0.15). We thus encourage the systematic and careful consideration of the form and mobility of P in the experimental trials that aim to assess the role of biological complexity on plant P nutrition.

scholarly journals The Mediterranean Diet, a Rich Source of Angiopreventive Compounds in Cancer

Nutrients ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 2036 ◽  
Author(s):  
Beatriz Martínez-Poveda ◽  
José Antonio Torres-Vargas ◽  
María del Carmen Ocaña ◽  
Melissa García-Caballero ◽  
Miguel Ángel Medina ◽  
...  
Keyword(s):  
Mediterranean Diet ◽  
Essential Role ◽  
Chemopreventive Agents ◽  
Angiogenic Potential ◽  
Slowing Down ◽  
Interesting Approach ◽  
The Mediterranean ◽  
Tumor Growth And Metastasis ◽  
Early Phases

Diet-based chemoprevention of cancer has emerged as an interesting approach to evade the disease or even target its early phases, reducing its incidence or slowing down tumor progression. In its basis in the essential role of angiogenesis for tumor growth and metastasis, angioprevention proposes the use of inhibitors of angiogenesis in cancer prevention. The anti-angiogenic potential exhibited by many natural compounds contained in many Mediterranean diet constituents makes this dietary pattern especially interesting as a source of chemopreventive agents, defined within the angioprevention strategy. In this review, we focus on natural bioactive compounds derived from the main foods included in the Mediterranean diet that display anti-angiogenic activity, as well as their possible use as angiopreventive agents.

scholarly journals Seasonal predictability of Mediterranean weather regimes in the Copernicus C3S systems

2021 ◽  
Author(s):  
Ignazio Giuntoli ◽  
Federico Fabiano ◽  
Susanna Corti
Keyword(s):  
Mediterranean Region ◽  
Climate Models ◽  
Reanalysis Data ◽  
Seasonal Predictability ◽  
Economic Implications ◽  
Weather Regimes ◽  
Weather Patterns ◽  
The Mediterranean ◽  
Good Agreement

AbstractSeasonal predictions in the Mediterranean region have relevant socio-economic implications, especially in the context of a changing climate. To date, sources of predictability have not been sufficiently investigated at the seasonal scale in this region. To fill this gap, we explore sources of predictability using a weather regimes (WRs) framework. The role of WRs in influencing regional weather patterns in the climate state has generated interest in assessing the ability of climate models to reproduce them. We identify four Mediterranean WRs for the winter (DJF) season and explore their sources of predictability looking at teleconnections with sea surface temperature (SST). In particular, we assess how SST anomalies affect the WRs frequencies during winter focussing on the two WRs that are associated with the teleconnections in which the signal is more intense: the Meridional and the Anticyclonic regimes. These sources of predictability are sought in five state-of-the-art seasonal forecasting systems included in the Copernicus Climate Change Services (C3S) suite finding a weaker signal but an overall good agreement with reanalysis data. Finally, we assess the ability of the C3S models in reproducing the reanalysis data WRs frequencies finding that their moderate skill increases during ENSO intense years, indicating that this teleconnection is well reproduced by the models and yields improved predictability in the Mediterranean region.

scholarly journals A Comparative Assessment of the Chronic Effects of Micro- and Nano-Plastics on the Physiology of the Mediterranean Mussel Mytilus galloprovincialis

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 649
Author(s):  
Marco Capolupo ◽  
Paola Valbonesi ◽  
Elena Fabbri
Keyword(s):  
Mytilus Galloprovincialis ◽  
Acetylcholinesterase Activity ◽  
Particle Sizes ◽  
Glutathione S Transferase ◽  
Phase Ii Metabolism ◽  
Chronic Effects ◽  
Mediterranean Mussel ◽  
Metabolism Enzyme ◽  
The Mediterranean

The ocean contamination caused by micro- and nano-sized plastics is a matter of increasing concern regarding their potential effects on marine organisms. This study compared the effects of a 21-day exposure to 1.5, 15, and 150 ng/L of polystyrene microplastics (PS-MP, 3-µm) and nanoplastics (PS-NP, 50-nm) on a suite of biomarkers measured in the Mediterranean mussel Mytilus galloprovincialis. Endpoints encompassed immunological/lysosomal responses, oxidative stress/detoxification parameters, and neurotoxicological markers. Compared to PS-MP, PS-NP induced higher effects on lysosomal parameters of general stress. Exposures to both particle sizes increased lipid peroxidation and catalase activity in gills; PS-NP elicited greater effects on the phase-II metabolism enzyme glutathione S-transferase and on lysozyme activity, while only PS-MP inhibited the hemocyte phagocytosis, suggesting a major role of PS particle size in modulating immunological/detoxification pathways. A decreased acetylcholinesterase activity was induced by PS-NP, indicating their potential to impair neurological functions in mussels. Biomarker data integration in the Mussel Expert System identified an overall greater health status alteration in mussels exposed to PS-NP compared to PS-MP. This study shows that increasing concentrations of nanoplastics may induce higher effects than microplastics on the mussel’s lysosomal, metabolic, and neurological functions, eventually resulting in a greater impact on their overall fitness.

scholarly journals Formation Patterns of Mediterranean High-Mountain Water-Bodies in Sierra-Nevada, SE Spain

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 438
Author(s):  
Jose Luis Diaz-Hernandez ◽  
Antonio Jose Herrera-Martinez
Keyword(s):  
Sierra Nevada ◽  
Unknown Origin ◽  
Slope Instability ◽  
Water Bodies ◽  
High Mountain ◽  
Mountain Areas ◽  
Glacial Processes ◽  
The Mediterranean ◽  
Water Volumes

At present, there is a lack of detailed understanding on how the factors converging on water variables from mountain areas modify the quantity and quality of their watercourses, which are features determining these areas’ hydrological contribution to downstream regions. In order to remedy this situation to some extent, we studied the water-bodies of the western sector of the Sierra Nevada massif (Spain). Since thaw is a necessary but not sufficient contributor to the formation of these fragile water-bodies, we carried out field visits to identify their number, size and spatial distribution as well as their different modelling processes. The best-defined water-bodies were the result of glacial processes, such as overdeepening and moraine dams. These water-bodies are the highest in the massif (2918 m mean altitude), the largest and the deepest, making up 72% of the total. Another group is formed by hillside instability phenomena, which are very dynamic and are related to a variety of processes. The resulting water-bodies are irregular and located at lower altitudes (2842 m mean altitude), representing 25% of the total. The third group is the smallest (3%), with one subgroup formed by anthropic causes and another formed from unknown origin. It has recently been found that the Mediterranean and Atlantic watersheds of this massif are somewhat paradoxical in behaviour, since, despite its higher xericity, the Mediterranean watershed generally has higher water contents than the Atlantic. The overall cause of these discrepancies between watersheds is not connected to their formation processes. However, we found that the classification of water volumes by the manners of formation of their water-bodies is not coherent with the associated green fringes because of the anomalous behaviour of the water-bodies formed by moraine dams. This discrepancy is largely due to the passive role of the water retained in this type of water-body as it depends on the characteristics of its hollows. The water-bodies of Sierra Nevada close to the peak line (2918 m mean altitude) are therefore highly dependent on the glacial processes that created the hollows in which they are located. Slope instability created water-bodies mainly located at lower altitudes (2842 m mean altitude), representing tectonic weak zones or accumulation of debris, which are influenced by intense slope dynamics. These water-bodies are therefore more fragile, and their existence is probably more short-lived than that of bodies created under glacial conditions.

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