scholarly journals Excursions to C<sub>4</sub> vegetation recorded in the Upper Pleistocene loess of Surduk (Northern Serbia): an organic isotope geochemistry study

2013 ◽  
Vol 9 (3) ◽  
pp. 1001-1014 ◽  
Author(s):  
C. Hatté ◽  
C. Gauthier ◽  
D.-D. Rousseau ◽  
P. Antoine ◽  
M. Fuchs ◽  
...  

Abstract. Loess sequences have been intensively studied to characterize past glacial climates of the 40–50° north and south latitude zones. Combining different approaches of sedimentology, magnetism, geochemistry, geochronology and malacology allows the general pattern of the climate and environment of the last interglacial–glacial cycle in Eurasia and America to be characterized. Previous studies performed in Europe have highlighted the predominance (if not the sole occurrence) of C3 vegetation. The presence of C3 plants suggests a regular distribution of precipitation along the year. Therefore, even if the mean annual precipitation remained very low during the most extensive glacial times, free water was available for more than 2 months per year. Contrarily, the δ13C record of Surduk (Serbia) clearly shows the occurrence and dominance of C4 plants during at least 4 episodes of the last glacial times at 28.0–26.0 kyr cal BP, 31.4–30.0 kyr cal BP, 53.4–44.5 kyr cal BP and 86.8–66.1 kyr. The C4 plant development is interpreted as a specific atmospheric circulation pattern that induces short and dry summer conditions. As possible explanation, we propose that during "C4 episodes", the Mediterranean Sea would have been under the combined influence of the following: (i) a strong meridional circulation unfavorable to water evaporation that reduced the Mediterranean precipitation on the Balkans; and (ii) a high positive North Atlantic Western Russian (NA/WR)-like atmospheric pattern that favored northerlies over westerlies and reduced Atlantic precipitation over the Balkans. This configuration would imply very dry summers that did not allow C3 plants to grow, thus supporting C4 development. The intra-"C4 episode" periods would have occurred under less drastic oceanic and atmospheric patterns that made the influence of westerlies on the Balkans possible.

2013 ◽  
Vol 9 (1) ◽  
pp. 187-215 ◽  
Author(s):  
C. Hatté ◽  
C. Gauthier ◽  
D.-D. Rousseau ◽  
P. Antoine ◽  
M. Fuchs ◽  
...  

Abstract. Loess sequences have been intensively studied to characterize past glacial climates of the 40–50 ° North and South latitude zones. Combining different approaches of sedimentology, magnetism, geochemistry, geochronology and malacology allows the general pattern of the climate and environment of the last interglacial-glacial cycle in Eurasia and America to be characterized. Previous studies performed in Europe have highlighted the predominance (if not the sole occurrence) of C3 vegetation. The presence of C3 plants suggests a regular distribution of precipitation along the year. Therefore, even if the mean annual precipitation remained very low during the most extensive glacial times, free water was available for more than 2 months per year. Contrarily, the δ13C record of Surduk (Serbia) clearly shows the occurrence and dominance of C4 plants during at least 4 episodes of the last glacial times at [26.0–28.0], [30.0–31.4], [44.5–53.4] and [66.1–86.8] (in kyrs cal. B.P.). The C4 plant development is interpreted as a specific atmospheric circulation pattern that induces short and dry summer conditions. As possible explanation, we propose that during "C4 episodes", the Mediterranean Sea would have been under the combined influence of the following: (i) a strong meridional circulation unfavorable to water evaporation that reduced the Mediterranean precipitation on the Balkans; and (ii) a high positive North Atlantic Western Russian (NAWR)-like atmospheric pattern that favored northerlies over westerlies and reduced Atlantic precipitation over the Balkans. This configuration would imply very dry summers that did not allow C3 plants to grow, thus supporting C4 development. The intra "C4 episode" periods would have occurred under less drastic oceanic and atmospheric patterns that made the influence of westerlies on the Balkans possible.


Author(s):  
Konstantina Zanou

Transnational Patriotism in the Mediterranean, 1800–1850: Stammering the Nation investigates the long process of transition from a world of empires to a world of nation-states by narrating the biographies of a group of people who were born within empires but came of age surrounded by the emerging vocabulary of nationalism, much of which they themselves created. It is the story of a generation of intellectuals and political thinkers from the Ionian Islands who experienced the collapse of the Republic of Venice and the dissolution of the common cultural and political space of the Adriatic, and who contributed to the creation of Italian and Greek nationalisms. By uncovering this forgotten intellectual universe, Transnational Patriotism in the Mediterranean retrieves a world characterized by multiple cultural, intellectual, and political affiliations that have since been buried by the conventional narrative of the formation of nation-states. The book rethinks the origins of Italian and Greek nationalisms and states, highlighting the intellectual connection between the Italian peninsula, Greece, and Russia, and re-establishing the lost link between the changing geopolitical contexts of western Europe, the Mediterranean, and the Balkans in the Age of Revolutions. It re-inscribes important intellectuals and political figures, considered ‘national fathers’ of Italy and Greece (such as Ugo Foscolo, Dionysios Solomos, Ioannis Kapodistrias, and Niccolò Tommaseo), into their regional and multicultural context, and shows how nations emerged from an intermingling, rather than a clash, of ideas concerning empire and liberalism, Enlightenment and religion, revolution and conservatism, and East and West.


Diversity ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 239
Author(s):  
Maria Flavia Gravina ◽  
Cataldo Pierri ◽  
Maria Mercurio ◽  
Carlotta Nonnis Marzano ◽  
Adriana Giangrande

In the different mesophotic bioconstructions recently found along the Southeastern Italian coast, polychaetes have been proved to show high species richness and diversity, hitherto never investigated. In the present study, the species composition and functional role of polychaete assemblages were analysed; the updated key to identification of the Mediterranean species of genus Eunice was presented and some taxonomic issues were also discussed. On the total of 70 species Serpulidae and Eunicida were the dominant polychaetes. Facing similar levels of α-diversity, the polychaete assemblages showed a high turnover of species along the north-south gradient, clearly according to the current circulation pattern, as well as to the different bioconstructors as biological determinants. Indeed, Serpulidae were dominant on the mesophotic bioconstructions primarily formed by the deep-sea oyster Neopycnodonte cochlear, while the Eunicida prevailed on the mesophotic bioconstructions mainly built by scleractinians. Lastly, the record of Eunice dubitata was the first for the Mediterranean and Italian fauna and proved this species to be characteristic of mesophotic bioconstructions.


1946 ◽  
Vol 36 (4) ◽  
pp. 497-511 ◽  
Author(s):  
S. Adler

The sandflies of Cyprus have been examined. The following ten species were found: P. papatasii, P. perniciosus var. tobbi, P. chinensis (a local race), P. perfiliewi (rare), P. sergenti, P. alexandri, P. larroussei (rare), P. fallax cypriotica, var. n., P. azizi, sp. n., and P. parroti.Melanic forms of P. parroti were found. Melanism was associated with a reduction in the teeth of the pharynx in the female in the few specimens collected.The race of P. chinensis found on the island differs from those hitherto described.The general composition of the sandfly population of Cyprus is different from that of any other part of the Mediterranean examined.P. major which is common in Palestine, Syria and the Balkans was not found.Canine kala-azar is common on the island. P. perniciosus var. tobbi and a race of P. chinensis should be considered as possible carriers but this point must be determined experimentally.


2021 ◽  
Author(s):  
Paolo G. Albano ◽  
Anna Sabbatini ◽  
Jonathan Lattanzio ◽  
Jan Steger ◽  
Sönke Szidat ◽  
...  

&lt;p&gt;The Lessepsian invasion &amp;#8211; the largest marine biological invasion &amp;#8211; followed the opening of the Suez Canal in 1869 (81 years BP). Shortly afterwards, tropical species also distributed in the Red Sea appeared on Mediterranean shores: it was the dawn of what would become the invasion of several hundred tropical species. The time of the Suez Canal opening coincided with an acceleration in natural history exploration and description, but the eastern sectors of the Mediterranean Sea lagged behind and were thoroughly explored only in the second half of the 20&lt;sup&gt;th&lt;/sup&gt; century. Many parts are still insufficiently studied today. Baseline information on pre-Lessepsian ecosystem states is thus scarce. This knowledge gap has rarely been considered by invasion scientists: every new finding of species belonging to tropical clades has been assumed to be a Lessepsian invader.&lt;/p&gt;&lt;p&gt;We here question this assumption by radiocarbon dating seven individual tests of miliolids &amp;#8211; imperforated calcareous foraminifera &amp;#8211; belonging to five alleged non-indigenous species. Tests were found in two sediment cores collected at 30 and 40 m depth off Ashqelon, on the Mediterranean Israeli shelf. We dated one &lt;em&gt;Cribromiliolinella milletti &lt;/em&gt;(core at 40 m, 20 cm sediment depth), three &lt;em&gt;Nodophthalmidium antillarum &lt;/em&gt;(core at 40 m, 35 cm sediment depth), one &lt;em&gt;Miliolinella &lt;/em&gt;cf. &lt;em&gt;fichteliana &lt;/em&gt;(core at 30 m, 110 cm sediment depth), one &lt;em&gt;Articulina alticostata &lt;/em&gt;(core at 40 m, 35 cm sediment depth) and one &lt;em&gt;Spiroloculina antillarum &lt;/em&gt;(core at 30 m, 110 cm sediment depth). All foraminiferal tests proved to be of Holocene age, with a median calibrated age spanning between 749 and 8285 years BP. Only one test of &lt;em&gt;N. antillarum&lt;/em&gt; showed a 2-sigma error overlapping the time of the opening of the Suez Canal, but with a median age of 1123 years BP. Additionally, a thorough literature search resulted in a further record of &lt;em&gt;S. antillarum&lt;/em&gt; in a core interval dated 1820&amp;#8211;2064 years BP in Turkey.&lt;/p&gt;&lt;p&gt;Therefore, these foraminiferal species are not introduced, but native species. They are all circumtropical or Indo-Pacific and in the Mediterranean distributed mostly in the eastern sectors (only &lt;em&gt;S. antillarum&lt;/em&gt; occurs also in the Adriatic Sea). Two hypotheses can explain our results: these species are Tethyan relicts that survived the Messinian salinity crisis (5.97&amp;#8211;5.33 Ma) and the glacial periods of the Pleistocene in the Eastern Mediterranean, which may have never desiccated completely during the Messinian crisis and which may have worked as a warm-water refugium in the Pleistocene; or they entered the Mediterranean Sea from the Red Sea more recently but before the opening of the Suez Canal, for example during the Last Interglacial (MIS5e) high-stand (125,000 years BP) when the flooded Isthmus of Suez enabled exchanges between the Mediterranean and the Indo-Pacific fauna. The recognition that some alleged Lessepsian invaders are in fact native species influences our understanding of the invasion process, its rates and environmental correlates.&lt;/p&gt;


2021 ◽  
pp. 422-442
Author(s):  
Sharon E. J. Gerstel

Although few secular examples of Byzantine monumental painting survive, hundreds of churches throughout the Mediterranean and the Balkans preserve impressive decorative programs. Many of these churches are well studied. Others, however, remain unpublished. Close study of the paintings provides valuable information about techniques, materials, and artistic styles. Church decoration can show enormous regional variation: specific communities and patrons often exerted influence on subject matter. Inscriptions played an important role in many churches, providing an archive of liturgical texts to be spoken and sung and epigrams to be read. Liturgical texts, hymns, and ritual performance were important inspirations for painters and communities in the Middle and Late Byzantine periods. Phenomenological effects of sound and light were also considered in monumental decoration.


2016 ◽  
Vol 20 (8) ◽  
pp. 3183-3191 ◽  
Author(s):  
Wei Hu ◽  
Bing Cheng Si

Abstract. The scale-specific and localized bivariate relationships in geosciences can be revealed using bivariate wavelet coherence. The objective of this study was to develop a multiple wavelet coherence method for examining scale-specific and localized multivariate relationships. Stationary and non-stationary artificial data sets, generated with the response variable as the summation of five predictor variables (cosine waves) with different scales, were used to test the new method. Comparisons were also conducted using existing multivariate methods, including multiple spectral coherence and multivariate empirical mode decomposition (MEMD). Results show that multiple spectral coherence is unable to identify localized multivariate relationships, and underestimates the scale-specific multivariate relationships for non-stationary processes. The MEMD method was able to separate all variables into components at the same set of scales, revealing scale-specific relationships when combined with multiple correlation coefficients, but has the same weakness as multiple spectral coherence. However, multiple wavelet coherences are able to identify scale-specific and localized multivariate relationships, as they are close to 1 at multiple scales and locations corresponding to those of predictor variables. Therefore, multiple wavelet coherence outperforms other common multivariate methods. Multiple wavelet coherence was applied to a real data set and revealed the optimal combination of factors for explaining temporal variation of free water evaporation at the Changwu site in China at multiple scale-location domains. Matlab codes for multiple wavelet coherence were developed and are provided in the Supplement.


2017 ◽  
Vol 17 (9) ◽  
pp. 5893-5919 ◽  
Author(s):  
Eleni Marinou ◽  
Vassilis Amiridis ◽  
Ioannis Binietoglou ◽  
Athanasios Tsikerdekis ◽  
Stavros Solomos ◽  
...  

Abstract. In this study we use a new dust product developed using CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) observations and EARLINET (European Aerosol Research Lidar Network) measurements and methods to provide a 3-D multiyear analysis on the evolution of Saharan dust over North Africa and Europe. The product uses a CALIPSO L2 backscatter product corrected with a depolarization-based method to separate pure dust in external aerosol mixtures and a Saharan dust lidar ratio (LR) based on long-term EARLINET measurements to calculate the dust extinction profiles. The methodology is applied on a 9-year CALIPSO dataset (2007–2015) and the results are analyzed here to reveal for the first time the 3-D dust evolution and the seasonal patterns of dust over its transportation paths from the Sahara towards the Mediterranean and Continental Europe. During spring, the spatial distribution of dust shows a uniform pattern over the Sahara desert. The dust transport over the Mediterranean Sea results in mean dust optical depth (DOD) values up to 0.1. During summer, the dust activity is mostly shifted to the western part of the desert where mean DOD near the source is up to 0.6. Elevated dust plumes with mean extinction values between 10 and 75 Mm−1 are observed throughout the year at various heights between 2 and 6 km, extending up to latitudes of 40° N. Dust advection is identified even at latitudes of about 60° N, but this is due to rare events of episodic nature. Dust plumes of high DOD are also observed above the Balkans during the winter period and above northwest Europe during autumn at heights between 2 and 4 km, reaching mean extinction values up to 50 Mm−1. The dataset is considered unique with respect to its potential applications, including the evaluation of dust transport models and the estimation of cloud condensation nuclei (CCN) and ice nuclei (IN) concentration profiles. Finally, the product can be used to study dust dynamics during transportation, since it is capable of revealing even fine dynamical features such as the particle uplifting and deposition on European mountainous ridges such as the Alps and Carpathian Mountains.


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