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Journal articles on the topic 'Allochtonous'
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1
Zuidema, W., N. Tronchet, A. E. Luchtenburg, M. de Klerk, J. N. M. IJzermans, and W. Weimar. "NON-RESIDENT ALLOCHTONOUS LIVING KIDNEY DONORS." Transplantation 78 (July 2004): 510. http://dx.doi.org/10.1097/00007890-200407271-01375.
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Kolenčík, Marek, Peter Štrba, Gabriela Kratošová, and Illa Ramakanth. "Diversity of allochtonous substances detected in bee pollen pellets." Acta fytotechnica et zootechnica 20, no. 3 (September 30, 2017): 60–64. http://dx.doi.org/10.15414/afz.2017.20.03.60-65.
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Medeiros, Edgardo Ramos, Fabrício De Araújo Pedron, and Anderson Augusto Volpato Sccoti. "EVIDÊNCIAS DE PEDOGÊNESE ALÓCTONE SOBRE ARENITOS BOTUCATU NO SUDOESTE GAÚCHO." Ciência e Natura 35, no. 1 (October 22, 2013): 43. http://dx.doi.org/10.5902/2179460x9600.
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The southwestern region of Rio Grande do Sul (RS) is characterized by large portions of sandy soils that have high environmental vulnerability, due to their low fertility and high susceptibility to erosion. Some of these soils have increased clay, suggesting allochtonous pedogenesis. In this case, the aims of this study were to determine evidence of allochtonous pedogenesis on sandstones Botucatu Formation in the southwestern region of the RS. A profile of Argissolo Vermelho and other of Neossolos Quartzarênico were analyzed, both formed on quartz sandstones of the Botucatu formation. Through morphological, physical, chemical and mineralogical analysis was possible to verify the process of allochthonous pedogenesis by higher clay content in the B horizon of the Argissolo profile and confirmed by the absence of clay forming minerals in the rock and in the presence of ilmenite in the pedogenetic horizons and its absence in the rock matrix. The environmental conditions suggest that the ilmenite originates from alteration of the surrounding volcanic rocks.
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Treer, T., D. Matulić, G. Bogdanović, I. Aničić, R. Safner, M. Piria, N. Šprem, and T. Tomljanović. "The condition of allochtonous fishes in the Mediterranean Vransko Lake." Journal of Applied Ichthyology 27, no. 3 (November 20, 2010): 965–67. http://dx.doi.org/10.1111/j.1439-0426.2010.01610.x.
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Molerovic, Nikola, Bozidar Raskovic, Radica Djedovic, Ostojic Andric, Zoran Markovic, and Sasa Maric. "Characterization of the genetic structure of the brown trout (Salmo trutta) from “Braduljica” fish farm, Serbia." Biotehnologija u stocarstvu 35, no. 3 (2019): 289–99. http://dx.doi.org/10.2298/bah1903289m.
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Due to the ecological concerns and preservation of genetic resources, the characterization of genetic structure of the brown trout (Salmo trutta) was carried out on the "Braduljica" fish farm. DNA was isolated from fin clips of 10 individuals, and after that molecular PCR-RFLP methods were used for distinguishing between Atlantic and Danubian lineages based on control region of the mitochondrial DNA (CR mtDNA) and lactate dehydrogenase gene of the nuclear DNA (LDH nDNA). Based on phenotypic characteristics it was estimated that out of 10 individuals included in this study five belonged to the allochtonous Atlantic lineage and remaining five belonged to the native Danubian lineage of brown trout. However, results of molecular analyses showed a high percentage of allochthonous genes among the individuals, which confirms the hybridization between these two lineages. Also, the results showed that the selection based on the phenotype is not adequate. In order to continue with proper broodstock management, it is necessary to eliminate allochtonous individuals of the Atlantic lineage from the broodstock.
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Lövgren, J., M. Reinikainen, and L. Persson. "Allochtonous input and trophic level heterogeneity: impact on an aquatic food web." Oikos 115, no. 1 (July 12, 2006): 141–47. http://dx.doi.org/10.1111/j.2006.0030-1299.13737.x.
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Bobinac, Martin, Sinisa Andrasev, Marko Perovic, Andrijana Bauer-Zivkovic, and Djura Jorgic. "Italian alder (Alnus cordata/Loisel./Desf.) - new species for Allochtonous dendroflora of Serbia." Bulletin of the Faculty of Forestry, no. 111 (2015): 21–36. http://dx.doi.org/10.2298/gsf1511021b.
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The foreign tree species, Alnus cordata/Loisel./Desf. (Italian alder), (Betulaceae/Loisel./Duby), not previously recorded in the dendroflora of Serbia, is described in this paper. Italian alder trees in an experimental plot in the area of Erdevik, aged 11 years, show good vitality and fast growth, and bear fruits since their 10th year. Tree heights are in range from 10.4 to 16.2 m, and diameters at the breast height range from14.6 to 34.9 cm. The morphological properties of leaves, fruiting organs (?cones?) and male catkins are in concordance with the values in literature sources, although they show great variability. Since the time of plantation establishment, the absolute minimum air temperature in the nearby meteorological station of Sremska Mitrovica was -26.50C, so it can be assumed that the species is frost hardy. On the basis of the researched properties of Italian alder, it can be concluded that this species can be cultivated in Serbia as an ornamental in urban areas and as a fast growing species in forest plantations for biomass production.
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Shokasheva, D. I. "Specific features of long-term domestication of australian crayfish Cherax quadricarinatus in conditions of the western part of Russian Federation." Izvestiya TINRO 194 (October 12, 2018): 188–92. http://dx.doi.org/10.26428/1606-9919-2018-194-188-192.
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Natural populations of crayfish are in depression in Russia and local species are not cultivated. In this situation, experimental cultivation of allochtonous australian crayfish Cherax quadricarinatus is conducted. This species is distinguished by high reproductive abilities and good consumer properties. It has domesticated in Russia spontaneously and produced 9–10 generations in Astrakhan Region. Certain natural selection in the process of domestication provides adaptive ability of this species to local environments and its capability to reproduce a viable progeny, so there is no doubts in good prospects of its cultivation in industrial conditions.
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Zmudczyńska, Katarzyna, Izabela Olejniczak, Adrian Zwolicki, Lech Iliszko, Peter Convey, and Lech Stempniewicz. "Influence of allochtonous nutrients delivered by colonial seabirds on soil collembolan communities on Spitsbergen." Polar Biology 35, no. 8 (March 9, 2012): 1233–45. http://dx.doi.org/10.1007/s00300-012-1169-4.
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Situmorang, Dr B. "Emplacement Of The Meratus Ultrabasic Massif A Gravity Interpretation." Scientific Contributions Oil and Gas 10, no. 2 (April 14, 2022): 3–15. http://dx.doi.org/10.29017/scog.10.2.896.
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Based on gravity data, extensive outcrops of igneous ultrahasic rocks at Meranus Range in Southeast Kalimantan have been interpreted as part of oceanic crust emplaced onto the margin of the Sundaland. The Meratus ultrabasic massif appears to be a thin slab with relative thickness of 300 m, thickening to 350 m to the southeast. If terpentinization of ulrabasie rocks is taken into account, the thickness of the allochtonous masses will increase to 780 m. Considering the occurrence of similar rocks in Kukusan Mts, Laut Islard and the South Am of Sulawesi, we suggest that the Metsaas massif forms part of a larger oceanic enustal segment emplaced during the Middle Cretaceous obducrion.
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Cvetkovska-Gjorgievska, Aleksandra, Ivailo Dedov, Slavcho Hristovski, Mario Langourov, Stanislava Lazarevska, Dana Prelik, and Nikolay Simov. "NEW RECORDS OF ALLOCHTONOUS, INVASIVE AND PEST INVERTEBRATE SPECIES FROM THE REPUBLIC OF MACEDONIA." Ecologica Montenegrina 20 (February 23, 2019): 56–70. http://dx.doi.org/10.37828/em.2019.20.5.
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In this paper new data on allochtonous and invasive invertebrate species: Arion (Arion) cf. vulgaris Moquin-Tandon 1855, Cornu aspersum (O.F. Muller, 1774), Harmonia axyridis (Pallas, 1773), Acanthoscelides obtectus (Say, 1831), Trogoderma variabile Ballion, 1878, Stegobium paniceum (Linnaeus, 1758), Oxycarenus (s.str.) lavaterae (Fabricius, 1787), Corythucha ciliata (Say, 1832), Leptoglossus occidentalis Heidemann, 1910, Ceroplastes japonicus (Green, 1921), Pseudaulacaspis pentagona (Targioni Tozzetti, 1886) MacGillivray, 1921, Tuta absoluta (Meyrick, 1917) and Frankliniella occidentalis (Pergande, 1895) from Macedonia are presented. The study represents faunistic data synthesis from different parts of Macedonia, based on collecting efforts of several taxonomic experts. The results of the study help to outline the composition of non-native and invasive invertebrate fauna and to narrow gaps concerning the knowledge of their distribution and introduction in Macedonia.
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Niketić, Marjan, Gordana Tomović, Goran Anačkov, Mirjana Bartula, Slađana Đorđević, Vladan Đorđević, Suzana Đorđević-Milošević, et al. "Material on the annotated checklist of vascular flora of Serbia: Nomenclatural, taxonomic and floristic notes II." Bulletin of the Natural History Museum, no. 13 (2020): 87–169. http://dx.doi.org/10.5937/bnhmb2013087n.
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The paper propose nine new nomenclature combinations and indicate eight new synonyms. There are 12 taxa (species and subspecies) of vascular flora which are new for the flora of Serbia (of which nine are autochthonous and three 88 N iketić, M. etal. : Annotated Checklist of Vascular Flora of Serbia II allochtonous plants). An old or unreliable literature records for three autochthonous and one allochthonous plant in the flora of Serbia has been confirmed. Eight plant taxa are a novelty for proper Serbia, Vojvodina, or Kosovo and Metohija, and for three plants, presence in certain administrative units in Serbia has been proved. The last part of the paper contains information on eight taxa whose presence in Serbia or in its territorial units has been refuted.
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Di Gregorio, Simona, Paolo Maggioni, and Roberto Lorenzi. "Bioaugmentation of an allochtonous Ascomycetes for the depletion of the polychlorinated biphenyls (PCBs) in contaminated soils." New Biotechnology 33 (July 2016): S137. http://dx.doi.org/10.1016/j.nbt.2016.06.1198.
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Bárdossy, George, and Ó. Kovács. "A multivariate statistical and geostatistical study on the geochemistry of allochtonous karst bauxite deposits in Hungary." Nonrenewable Resources 4, no. 2 (June 1995): 138–53. http://dx.doi.org/10.1007/bf02259037.
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Zorina, Svetlana, Dmitry Ruban, and Loon Van. "A condensed succession at the Jurassic/Cretaceous transition in a shallowing basin on the eastern Russian Platform." Annales g?ologiques de la Peninsule balkanique, no. 70 (2009): 1–8. http://dx.doi.org/10.2298/gabp0970001z.
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The eastern periphery of the Russian Platform houses an exceptional record of the Jurassic/Cretaceous transition, which is represented by very thin sandstone beds. The presence of glaucony grains, phosphorite concretions and shark teeth indicates that the transitional sediments constitute a condensed succession, although the allochtonous origin of the glaucony grains in itself is not a reliable indicator. The combination with thin ammonite zones and a strongly diminished sedimentation rate, as low as ~0.05 cm/ka are, however, convincing evidence. The Jurassic/Cretaceous transitional deposits accumulated in a basin the depth of which decreased simultaneously with a global eustatic sea-level fall. This coincidence suggests that condensed successions may form in shallowing environments, which contradicts the sequence-stratigraphic concept. Considering the character of the sediments under study, it appears that both stratigraphic and taphonomic condensation patterns occur in this part of the eastern Russian Platform.
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Ouahmane, L., J. Thioulouse, M. Hafidi, Y. Prin, M. Ducousso, A. Galiana, C. Plenchette, M. Kisa, and R. Duponnois. "Soil functional diversity and P solubilization from rock phosphate after inoculation with native or allochtonous arbuscular mycorrhizal fungi." Forest Ecology and Management 241, no. 1-3 (March 2007): 200–208. http://dx.doi.org/10.1016/j.foreco.2007.01.015.
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Hammer-Dedet, Florence, Estelle Jumas-Bilak, and Patricia Licznar-Fajardo. "The Hydric Environment: A Hub for Clinically Relevant Carbapenemase Encoding Genes." Antibiotics 9, no. 10 (October 15, 2020): 699. http://dx.doi.org/10.3390/antibiotics9100699.
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Carbapenems are β-lactams antimicrobials presenting a broad activity spectrum and are considered as last-resort antibiotic. Since the 2000s, carbapenemase producing Enterobacterales (CPE) have emerged and are been quickly globally spreading. The global dissemination of carbapenemase encoding genes (CEG) within clinical relevant bacteria is attributed in part to its location onto mobile genetic elements. During the last decade, carbapenemase producing bacteria have been isolated from non-human sources including the aquatic environment. Aquatic ecosystems are particularly impacted by anthropic activities, which conduce to a bidirectional exchange between aquatic environments and human beings and therefore the aquatic environment may constitute a hub for CPE and CEG. More recently, the isolation of autochtonous aquatic bacteria carrying acquired CEG have been reported and suggest that CEG exchange by horizontal gene transfer occurred between allochtonous and autochtonous bacteria. Hence, aquatic environment plays a central role in persistence, dissemination and emergence of CEG both within environmental ecosystem and human beings, and deserves to be studied with particular attention.
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Perruchot, A., C. Dupuis, E. Brouard, D. Nicaise, and R. Ertus. "L'halloysite karstique: comparaison des gisements types de Wallonie (Belgique) et du Perigord (France)." Clay Minerals 32, no. 2 (June 1997): 271–87. http://dx.doi.org/10.1180/claymin.1997.032.2.08.
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AbstractTwo cryptokarstic (covered karsts) halloysitic deposits were compared: the Entre Sambre et Meuse in Belgium and the Périgord in France. Both belong to a continental margin subject to marine transgression and regression cycles which enhance the karstic activity. This geodynamic context appears to be very favourable to the formation of halloysite. The similarity of the geodynamic context of both sites leads to a genetic convergence linked to specific properties of the cryptokarstic system, especially, the ability to collect the percolating waters and to juxtapose the conditions of precipitation, accumulation and maturation of the halloysite silico-aluminous gel precursors. However, each site also displays pronounced specificities relevant to: the nature of the host rock of the halloysite (a partly silicified limestone in the first, a smectite-kaolinite argilite in the second); the aluminium source (allochtonous in the first, relatively autochtonous in the second); and the halloysite content of the deposits (of ∼ 100% in the first, and 40% maximum in the second).
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Pokrovsky, O. S., L. S. Shirokova, S. N. Kirpotin, S. Audry, J. Viers, and B. Dupre. "Effect of permafrost thawing on the organic carbon and trace element colloidal speciation and microbial activity in thermokarst lakes of Western Siberia." Biogeosciences Discussions 7, no. 6 (November 2, 2010): 8041–86. http://dx.doi.org/10.5194/bgd-7-8041-2010.
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Abstract. In order to understand the mechanisms of carbon mobilization and biodegradation during permafrost thawing and to establish the link between the organic carbon (OC), and other chemical and microbiological parameters in forming thermokarstic (thaw) lakes, we studied biogeochemistry of OC and trace elements (TE) in a chronosequence of small lakes that are being formed due to permafrost thawing in the northern part of Western Siberia. About 20 lakes and small ponds of various sizes and ages were sampled for dissolved and colloidal organic carbon and metals and culturable heterotrophic bacterial cell number. We observed a sequence of ecosystem stages corresponding to the evolution from peat thawing and palsa degradation due to permafrost subsidence in small ponds to large, km – size lakes subject to drainage and, finally, the khasyrey (drained lake) formation. There is a systematic evolution of both total dissolved and colloidal concentration of OC and TE in the lake water along the chronosequence of lake development that may be directly linked to microbial mineralization of dissolved organic matter and liberation of the mineral part (Fe, Al, TE) from organo-mineral colloids. In this chronosequence of lake development, we observe a clear decrease of the relative proportion of <1 kDa (1 kDa~1 nm) OC concentration along with concentration of total dissolved (<0.45 μm) OC. This is accompanied by an increase of the small size organic ligands (probably autochtonous exometabolites produced by the phytoplankton) and a concomitant decrease of the proportion of large-size organic (humic) complexes having allochtonous (soil) origin. This evolution may be due to the activity of heterotrophic bacterioplancton that uses allochtonous organic matter and dissolved nutrients originated from the peat lixiviation. Most insoluble TE demonstrate a systematic decrease of concentration during filtration (5 μm, 0.45 μm) exhibiting a similar pattern among different samples. At the same time, there is an increase of the relative proportion of large size particles over <1 kDa fraction for most insoluble elements along the chronosequence of lake evolution. TE are likely to be bound to colloidal OC but also coprecipitated with the mineral (Fe, Al) part of colloids. Upon progressive consumption of dissolved OC by heterotrophic bacteria, there is a liberation of Fe, Al, and insoluble TE in the water column that may be subjected to coagulation in the form of particles or large-size mineral colloids.
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Lavadinović, Vukan M., Dejan Beuković, and Zoran Popović. "Common Pheasant (Phasianus colchicus L.1758) Management in Serbia." Contemporary Agriculture 68, no. 3-4 (December 1, 2019): 71–79. http://dx.doi.org/10.2478/contagri-2019-0012.
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Summary The common pheasant (Phasianus colchicus L. 1758) is an allochtonous game species of great importance to the hunting sector in Serbia. Growing concerns over a decline in its population raise issues about the proper management and hunting of common pheasants. As this research tends to identify the importance of common pheasants to Serbian hunters, the present study is based on a mixed research model combining traditional analyses with social studies on Serbian hunters. The data utilized have been collected from the annual management plans of 272 hunting grounds across Serbia and the interviews with 377 hunters. The results obtained suggest that there are significant differences between the analyzed variables in the management plans examined, which indicates that the pheasant hunting management in Serbia is not harmonized. However, the social studies conducted identify the common pheasant as the most hunted and popular game species with Serbian hunters. Accordingly, the common pheasant hunting and management in Serbia has to be improved in order to meet the hunters’ expectations and ensure their satisfaction.
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Veniale, F., A. Delgado, L. Marinoni, and M. Setti. "Dickite genesis in the ‘varicoloured’ clay-shale formation of the Italian Apennines: an isotopic approach." Clay Minerals 37, no. 2 (June 2002): 255–66. http://dx.doi.org/10.1180/0009855023720032.
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AbstractDickite occurs over wide areas along the Italian Apennines strip throughout Italy, mainly in the allochtonous ‘varicoloured’ clay-shale formation. Morphological, fabric and crystallochemical features suggest an authigenic origin, from pore solutions. The nature of the solutions and the process of dickite formation, including hydrothermalism, diagenesis or supergene evolution have all been discussed. Stable isotope analysis (O, H) was performed to investigate these points. The δD values of dickite range between −63.7 and −79.1% (SMOW) and δ18O between +21% and +16.1‰ (SMOW), and are similar to those reported for kaolinites formed in equilibrium with meteoric waters. The data fall along the ‘Line of Meteoric Kaolinites’, supporting an origin involving meteoric waters and low temperatures. The isotopic compositions of the waters are within the range of Apennines meteoric water, and the temperatures derived are close to surface conditions. Contributions of diagenetic, hydrothermal or metamorphic waters must be discounted. The authigenic dickite from ‘varicoloured’ clays of the Italian Apennines formed by precipitation from flushing meteoric waters whose ingress was favoured by repeated surface erosion.
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Battisti, Corrado, Michele Cento, Fulvio Fraticelli, Steven Hueting, and Sergio Muratore. "Vertebrates in the “Palude di Torre Flavia” Special Protection Area (Lazio, central Italy): an updated checklist." Natural History Sciences 8, no. 1 (May 3, 2021): 3–28. http://dx.doi.org/10.4081/nhs.2021.509.
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Here we present the checklist of the vertebrates of the “Palude di Torre Flavia”, a protected area in Tyrrhenian central Italy (Special Protection Area according to the Directive 2009/147/EC). To draw up the checklist, we collated all the records found in the literature, in private collections, and in the Ornitho.it website database, as well as sporadic historical observations. We obtained evidence documented between 1981 and 2020 for 291 taxa of which 259 native, 26 allochthonous and 6 domesticated species in 5 classes: 5 actinopterygians (4 native species and 1 allochtonous), 2 amphibians, 20 reptiles (11 native species and 9 allochthonous; the last being all freshwater terrapins), 244 birds (including 14 non-native taxa and 6 domestic forms) and 20 mammals (including 2 allochthonous). Forty-three species are listed as of conservation concern on a national scale. The area has shown to be an important biodiversity hotspot, and a major stopover site for migrating birds. Further research should be focused on some still poorly investigated taxonomic groups, in particular: Actinopterygii, Amphibia Salamandridae, Carnivora Mustelidae, and Chiroptera.
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Van Iten, Heyo, Mario E. Cournoyer, and Michelle Coyne. "Designation of a neotype and paraneotype for Conularina triangulata (Raymond, 1905) (Upper Ordovician, eastern North America)." Journal of Paleontology 94, no. 4 (January 20, 2020): 796–97. http://dx.doi.org/10.1017/jpa.2019.110.
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Conularina triangulata (Raymond, 1905), the genotype of Conularina Sinclair, 1942, is a rare, early Late Ordovician conulariid (Cnidaria, Scyphozoa; Van Iten et al., 2006) having three sides or faces instead of four (Sinclair, 1942, fig. 9; Van Iten, 1992, text-fig. 3E). Originally described from the Valcour Formation (early Sandbian; Dix et al., 2013) on Valcour Island, New York (Sinclair, 1942), C. triangulata has since been found in laterally equivalent strata of the upper Laval Formation (‘Upper Chazy’; Sinclair, 1942) in Laval, Québec, Canada (Sinclair, 1942). From this same unit and area, Sinclair (1942) erected three new, four-sided species of Conularina (C. irrasa, C. raymondi, and C. undosa), and he erected a single four-sided species (C. narrawayi) from the Ottawa Formation (now the Sandbian–Katian Ottawa Group; Dix et al., 2013) at Tétreauville (now Gatineau), Québec. Subsequently, Jerre (1994) reported the occurrence of two species of Conularina in the Upper Ordovician of Sweden. Jerre (1994) also proposed that Eoconularia? forensis Sinclair, 1946 from the Upper Ordovician Citadelle Formation (‘Quebec City’ Formation; Sinclair, 1946) in Québec City, Québec (Promontoire de Québec thrust sheet, Appalachian Humber Zone, Allochtonous Domain; Castonguay et al., 2002) is a species of Conularina.
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Beran, Luboš. "Vodní měkkýši nově vzniklého jezera Most v severních Čechách [Freshwater molluscs of the Most, a newly created lake in Northern Bohemia (Czech Republic)]." Malacologica Bohemoslovaca 12 (December 1, 2013): 89–92. http://dx.doi.org/10.5817/mab2013-12-89.
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This paper summarizes the knowledge of freshwater mollusc fauna of the Most Lake. It was created in 2008–2013 by flooding of the majority of the former coal quarry of Ležáky (Northern Bohemia). This water reservoir originated in the area of 311 ha and with the maximum depth of 75 m it is the largest water body of the area. The research was conducted in summer 2013, when the water level was about 0.5 m bellow the final expected level. In total, only six species of freshwater molluscs (five gastropods, one bivalve) were found at 11 sites. Two autochtonous molluscs (Radix auricularia and Gyraulus crista) and four allochtonous species (Physella acuta, Gyraulus parvus, Menetus dilatatus and Dreissena polymorpha) were found. The occurrence of all species except D. polymorpha was scattered, while the latter occurred in numerous populations sometimes with more than 80 specimens per 10 cm². Most of the molluscs were found on stones of the lake banks or at areas of shallow water. The results obtained during this research have recorded mollusc assemblages at the first successional stages of this artificial lake, thus enabling future comparison.
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Vacek, Stanislav, Pavla Hejcmanová, Michal Hejcman, and Zdeněk Vacek. "Growth, healthy status and seed production of differently aged allochtonous and autochtonous Pinus mugo stands in the Giant Mts. over 30 years." European Journal of Forest Research 132, no. 5-6 (August 4, 2013): 801–13. http://dx.doi.org/10.1007/s10342-013-0721-2.
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Gadd, Nelson R. "Maximum age for a concretion at Green Creek, Ontario." Géographie physique et Quaternaire 34, no. 2 (January 28, 2011): 229–38. http://dx.doi.org/10.7202/1000400ar.
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Wood (? Salix sp.) from a concretionary nodule found at - 43 m a.s.l. at the Green Creek, Ontario, site was dated at 9 960 ± 820 BP (GSC-2498). The carbonate concretion has an apparent age of 14 400 ± 250 BP (GSC-2530). The wood date is a maximum age for the enclosing sediment and for its cementation; the carbonate date appears anomalous. At the time of the upper limit of error for the wood date (10 780 BP) Champlain Sea stood at or above 100 m a.s.l. The true age of the wood probably is compatible with that of freswhater shells at - 53 m a.s.l. at Bourget, Ontario (10 200 ± 90; GSC-1968), and of wood at - 61 m a.s.l. at Hawkesbury, Ontario (9 860 ± 330; BGS-257). Terrace sediments at ~ 43 m a.s.l. probably are of freshwater origin. Terrestrial and freshwater flora and fauna in earlier collections of concretions from Green Creek also suggest an estuarine to freswhater environment for the enclosing sediments. Occurrence of complete skeletons of fish and other vertebrates in concretions is related to chemically induced carbonate cementation during early stages of putrefaction of soft-bodied animals. This could preserve skeletal remains through several cycles of erosion. Therefore some concretions carry fossil remains that may be allochtonous to the sediment in which they now occur.
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Margielewski, Włodzimierz, Adam Michczyński, and Andrzej Obidowicz. "Records of the Middle - And Late Holocene Palaeoenvironmental Changes in the Pcim-Sucha Landslide Peat Bogs (Beskid Makowski Mts., Polish Outer Carpathians)." Geochronometria 35, no. -1 (January 1, 2010): 11–23. http://dx.doi.org/10.2478/v10003-010-0009-1.
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Records of the Middle - And Late Holocene Palaeoenvironmental Changes in the Pcim-Sucha Landslide Peat Bogs (Beskid Makowski Mts., Polish Outer Carpathians)The paper presents analysis of depositional sequences of two peat bogs situated in the depressions developed within the landslide landforms Pcim Sucha in the Beskid Makowski Mts. (Outer Carpathians). The older peat bog, with depositional sequence 3.75 m long, started to form at the decline of the Boreal Phase ca 7570-7330 cal BC. Palynological and lithological analyses as well as numerous (18) radiocarbon datings of different horizons in the sediment enabled reconstruction of palaeoenvironmental changes of the Middle and Late Holocene. Increase in climate humidity at the beginning of the Atlantic, Subboreal and Subatlantic Phases were observed as deliveries of minerogenic material to the peat bog basin and formation of illuvial and mineral layers within peat. The particularly intensive delivery of allochtonous material to the peat bog took place at the beginning of the Subatlantic Phase and was the result of both significant humid climate and increased human impact (colonization of the Przeworsk Culture) in the landslide area. Rejuvenation of the landslide zone and formation of the second landslide were connected with this period and processes. Deposits of peat bog situated within this younger landslide, which are ca 1.3 m thick, are significantly contaminated with mineral material.
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Manga, Veronica Ebot, Gladys Nchang Neba, and Emmanuel Cheo Suh. "Environmental Geochemistry of Mine Tailings Soils in the Artisanal Gold Mining District of Betare -Oya, Cameroon." Environment and Pollution 6, no. 1 (March 31, 2017): 52. http://dx.doi.org/10.5539/ep.v6n1p52.
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Changes in trace element concentrations in mine tailings (dry and wet) were investigated in the gold mining area of Bétaré-Oya, Eastern Cameroon. Forty-one surface sediment samples were analyzed using ICP-MS for heavy metals and pollution was assessed using Enrichment Ratio and Geo Accumulation Index (Igeo); using a sample from a remote area as control.Trace elements in mine tailings show significant increase compared to the background (control) values, with the exception of Sr and Nb. It is suggested that allochtonous deposition may account for Sr distribution. A strong correlation is observed between the lithophile elements; Y, Nb, Ce, La, and Pb. Their association with each other is also strong, i.e. Nb/Ce (.73) and La/Ce (.63). The close association of these elements in the samples may be an indication of the effect of resistant heavy minerals from felsic rocks (mainly granites and gneisses). Cu, Zn, Sr and Ba distribution is associated with mineralisation of sulphide-bearing minerals and clay formation from weathering of mica schist. Cu, Zn, As, W, Mo and Ag have been identified as potential pollutants. Compared to the Dutch soil quality guidelines, these elements are above the target values and below the intervention levels. Arsenic is considered to be the most threatening element, with regards to its potency. The distribution of As in this area appears to be controlled by mining activities.
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Gahramanov, G., M. Babayev, S. Shpyrko, and Kh Mukhtarova. "SUBSIDENCE HISTORY AND HYDROCARBON MIGRATION MODELING IN SOUTH CASPIAN BASIN." Visnyk of Taras Shevchenko National University of Kyiv. Geology, no. 1 (88) (2020): 82–91. http://dx.doi.org/10.17721/1728-2713.88.12.
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We study the mechanisms of migration and spacial distribution of hydrocarbon deposits along a regional 1000 km long SW - NE seismic cross section of the South Caspian Basin. A retrospective 2D geological simulation of basin subsidence and sediment filling history is performed taking into account accompanying processes of thermal and catagenetic transformations of organic matter, and subsequent migration and accumulation of hydrocarbons. The start of the basin opening with accumulation of considerable sedimentary mass can be dated as middle Mesozoic (Triassic or Jurassic), and hydrocarbon prone horizons can now be located at depths of 12 km. The hydrocarbon saturation of the Pliocene Productive Series is of epigenetic (allochtonous) nature, which is also confirmed in literature by geochemical data from mud volcanoes and by other facts. Geochemical age, depth of provenance and reworking degree of hydrocarbons point at generation sources in Mesozoic (gas) and Paleogene-Miocene formations (oil) with only subordinate participation of the lower "Productive Series" Pliocene suites. The dominant migration pattern of fluids is interformational (interstratal) intermittent injective subvertical flow along disjunctive planes, zones of increased fracturing and loose rocks, diapir intrusion contacts, eruptives of mud volcanoes, lithofacial unconformities and other structures, breaking the rocks continuity. This implies the possibility of commercial-scale accumulations of hydrocarbons at ultra high depths, if trap structures of sufficiently large sizes are available, comparable with already discovered giant oil and gas fields (Shah-Deniz, Azeri-Chirag-Gyuneshli etc).
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Tchoumatchenco, Platon, Dragoman Rabrenovic, Vladan Radulovic, Nenad Malesevic, and Barbara Radulovic. "Trans-border (north-east Serbia/north-west Bulgaria) correlations of the Jurassic lithostratigraphic units." Annales g?ologiques de la Peninsule balkanique, no. 72 (2011): 1–20. http://dx.doi.org/10.2298/gabp1172001t.
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Herein, correlations of the Jurassic sediments from NE Serbia with those of NW Bulgaria are made. The following Jurassic palaeogeographic units: the Eastern Getic, the Infra-Getic and the Moesian Platform are included in the study. The East Getic was studied in the outcrops near Rgotina, where the sedimentation started in the Hettangian and continued during the Callovian-Late Jurassic and is represented by platform carbonates. The Infra-Getic is documented by the sections of Dobra (Pesaca) and the allochtonous sediments near the Stubik. Very important for the Infra-Getic are the Late Jurassic volcano-sedimentary deposits of the Vratarnica Series, which crop out near Vratarnica Village. The Jurassic Moesian platform was studied in the sections near D. Milanovac and Novo Korito (Serbia) and in their prolongation in NW Bulgaria into the Gornobelotintsi palaeograben. Very important are the correlation in the region of Vrska Cuka (Serbia) and Vrashka Chuka (Bulgaria) - Rabisha Village (Magura Cave). A revision of the Jurassic sediments on the Vidin palaeohorst, which were studied in the Belogradchik palaeohorst, Gorno-Belotintsi palaeograben, Belimel palaeohorst and the Mihaylovgrad palaeograben, is made. The sedimentation on the Vidin palaeohorst started during different parts of the Middle Jurassic, and in the Mihaylovgrad palaeograben during the Hettangian (Lower Jurassic) where the sediments were deposited in relatively deeper water conditions. To south, the relatively shallow water sediments deposited on the Jurassic Vratsa palaeohorst on the southern board of the Mihaylovgrad palaeograben are described.
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Searle, Michael P. "Structural geometry, style and timing of deformation in the Hawasina Window, Al Jabal al Akhdar and Saih Hatat culminations, Oman Mountains." GeoArabia 12, no. 2 (April 1, 2007): 99–130. http://dx.doi.org/10.2113/geoarabia120299.
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ABSTRACT The Al Jabal al Akhdar and Saih Hatat culminations in the central Oman Mountains expose the complete mid-Permian to Late Cretaceous (Cenomanian) passive shelf and margin carbonate sequence beneath the allochtonous slope (Sumeini Group), basin (Hawasina complex), distal ocean-trench (Haybi complex) facies rocks, and the Semail ophiolite thrust sheets that were emplaced from NE to SW during the Late Cretaceous. Reconstruction of the pre-thrust sequences shows that time-equivalent rocks occur in successively stacked thrust sheets from shelf to slope to basin. The Al Jabal al Akhdar structure is a 60 km wavelength anticline plunging to the northwest beneath the Hawasina Window and with a fold axis that curves from WNW-ESE (Jabal Shams) to NNE-SSW (Jabal Nakhl). The structure shows little internal deformation except for minor intra-formational thrust duplexing within the Cretaceous shelf stratigraphy along the northern margin. The upper structural boundaries around the flanks of the shelf carbonate culminations have been re-activated as late stage normal faults. The Semail thrust formed a passive roof fault during late-stage culmination of al Al Jabal al Akhdar such that the ophiolite rests directly on Wasia Formation top-shelf with the entire Sumeini, Hawasina and Haybi thrust sheets displaced around the margins. NE-directed backthrusting and intense folding in the northern part of the Hawasina Window affects all allochtonous units and is related to a steep ramp in the Late Cretaceous shelf margin at depth. The Saih Hatat culmination is another 40 km half-wavelength anticline in the central Oman Mountains, but shows extreme deformation in the form of recumbent folds, sheath folds with NNE-trending axes and thrusting along the northern margin. High-pressure carpholite, blueschist and eclogite facies rocks are exposed at successively deeper structural levels, separated by high-strain normal sense shear zones. There is no evidence for a separate ‘North Muscat microplate’ or an intra-continental subduction zone, as previously proposed; all high-pressure units can be restored to show their pre-deformation palaeographic positions along the northern margin of the Arabian Plate. Both Al Jabal al Akhdar and Saih Hatat are Late Cretaceous culminations, folded after obduction of the Hawasina, Haybi and Semail ophiolite thrust sheets from northeast to southwest during the period Turonian to Campanian-Lower Maastrichtian. Maximum compressive stress along the central Oman Mountains was oriented NE-SW, parallel to the ophiolite emplacement direction, but a second compressive stress axis was oriented WNW-ESE, either concurrently or slightly later in time, resulting in a dome and basin structural geometry. The biaxial fracture pattern in the foreland, southwest of the Oman Mountains could be explained as a result of the WNW-directed emplacement of the Masirah ophiolite belt and Batain mélange during the Campanian-early Palaeocene. Both Al Jabal al Akhdar and Saih Hatat were positive topographic features at the end of the Cretaceous with Upper Maastrichtian and Palaeogene sediments onlapping both flanks. In Jabal Abiad, these Palaeogene sediments have been uplifted by at least 2 km since the Late Miocene-Early Oligocene associated with minor NNE-SSW compression. Tertiary shortening, folding and thrusting increases to the north in the Musandam peninsula where the first effects of the Arabian Plate-Eurasian Plate (Zagros belt) continent-continent collision are seen.
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Civitarese, G., M. Gačić, M. Lipizer, and G. L. Eusebi Borzelli. "On the impact of the Bimodal Oscillating System (BiOS) on the biogeochemistry and biology of the Adriatic and Ionian Seas (Eastern Mediterranean)." Biogeosciences 7, no. 12 (December 15, 2010): 3987–97. http://dx.doi.org/10.5194/bg-7-3987-2010.
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Abstract. Analysis of 20-year time-series of the vertically averaged salinity and nutrient data in the Southern Adriatic shows that the two parameters are subject to strong decadal variability. In addition, it is documented that nutrient and salinity variations are out of phase. Nutrients in the Ionian and in the Adriatic vary in parallel except that generally the nutrient content in the Adriatic is lower than in the Ionian, a fact that has been attributed to primary producer consumption following the winter convective mixing. As shown earlier, North Ionian Gyre (NIG) changes its circulation sense on a decadal scale due to the Bimodal Oscillating System, i.e. the feedback mechanism between the Adriatic and Ionian. Cyclonic circulation causes a downwelling of the nitracline along the borders of the NIG and a decrease in the nutrient content of the water flowing into the Adriatic across the Otranto Strait, and vice versa. In addition, the highly oligotrophic central area of the Ionian shows annual blooms only during cyclonic NIG circulation. Inversion of the sense of the NIG results in the advection of Modified Atlantic Water or of the Levantine/Eastern Mediterranean waters in the Adriatic. Here, we show that the presence of allochtonous organisms from Atlantic/Western Mediterranean and Eastern Mediterranean/temperate zone in the Adriatic are concurrent with the anticyclonic and cyclonic circulations of the NIG, respectively. On the basis of the results presented, a revision of the theory of Adriatic ingressions formulated in the early 1950s is proposed.
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Bouillon, S., T. Moens, and F. Dehairs. "Carbon sources supporting benthic mineralization in mangrove and adjacent seagrass sediments (Gazi Bay, Kenya)." Biogeosciences Discussions 1, no. 1 (August 6, 2004): 311–33. http://dx.doi.org/10.5194/bgd-1-311-2004.
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Abstract. The origin of carbon substrates used by in situ sedimentary bacterial communities was investigated in an intertidal mangrove ecosystem and in adjacent seagrass beds in Gazi bay (Kenya) by δ13C analysis of bacteria-specific PLFA (phospholipid fatty acids) and bulk organic carbon. Export of mangrove-derived organic matter to the adjacent seagrass-covered bay was evident from sedimentary total organic carbon (TOC) and δ13CTOC data. PLFA δ13C data indicate that the substrate used by bacterial communities varied strongly and that exported mangrove carbon was a significant source for bacteria in the adjacent seagrass beds. Within the intertidal mangrove forest, bacterial PLFA at the surface layer (0-1 cm) typically showed more enriched δ13C values than deeper (up to 10 cm) sediment layers, suggesting a contribution from microphytobenthos and/or inwelled seagrass material. Under the assumption that seagrasses and mangroves are the dominant potential end-members, the estimated contribution of mangrove-derived carbon to benthic mineralization in the seagrass beds (16-74%) corresponds fairly well to the estimated contribution of mangrove C to the sedimentary organic matter pool (21-71%) across different seagrass sites. Based on these results and a compilation of literature data, we suggest that allochtonous carbon trapped in seagrass beds may often represent a significant fraction of the substrate for benthic mineralization - both in cases where seagrass C dominates the sediment TOC pool and in cases where external inputs are significant. Hence, it is likely that community respiration data systematically overestimate the role of mineralization in the overall seagrass C budget.
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Brunel, Maurice, and Jean-Robert Kienast. "Étude pétro-structurale des chevauchements ductiles himalayens sur la transversale de l'Everest–Makalu (Népal oriental)." Canadian Journal of Earth Sciences 23, no. 8 (August 1, 1986): 1117–37. http://dx.doi.org/10.1139/e86-111.
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Tectonic and microtectonic data in eastern Nepal indicate that the major observed thrusting (100 km) on the Main Central Thrust (MCT) postdates the Barrovian metamorphism of the High Himalaya gneisses. This result, at variance with the famous "reverse metamorphism model," better explains the abnormal metamorphic superpositions in the Himalayas and accounts for the lack of high-pressure assemblages under the thick, allochtonous High Himalaya Tibetan slab.Pressure and temperature estimates by microprobe analysis on plagioclase, biotite, garnet, kyanite, sillimanite, and cordierite assemblages are presented for samples collected along the MCT shear zone and across the gneiss slab in the Everest–Makalu area. Since there is very little difference in pressure at the front of the slab (Kathmandu Klippe) and its root, these estimates support the existence of important late metamorphic thrusting. The decrease of pressure towards the top of the gneiss pile, combined with a small temperature increase, explains the kyanite–sillimanite transition. The reverse metamorphism model, which implies refolded isograds, predicts heat loss by conduction throughout the sole of the thrust; pressure–temperature variations and kyanite–sillimanite transition phases more likely reflect a late heat supply in the upper part of the gneisses. Intrusion of leucogranitic bodies, confined to the interface with the Tethyan sediments, could account for this heat supply.A new tectonic evolution model of the Himalayan intracrustal thrusts is discussed. Without completely denying the existence of a reverse metamorphism synchronous with the phases of early shearing, it can be shown that the metamorphic zonation seen at present was governed by the structure of the later shearing.
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Volkov, Anatoly F. "Spatial-temporal patterns of euphausiids ecology in the Okhotsk Sea." Izvestiya TINRO 180, no. 1 (March 30, 2015): 128–39. http://dx.doi.org/10.26428/1606-9919-2015-180-128-139.
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The most common regularities in spatial distribution of mass Euphausia species and their size classes and ontogenetic stages are determined for the Okhotsk Sea using the data averaging by biostatistical areas and applying the average results to the centers of the areas that allows to smooth small-scale patterns as patchiness. Thysanoessa raschii and Th. inermis occupy mostly shelf areas and Th. longipes and Euphausia pacifica - deep-water areas; among them Th. raschii and Th. longipes are more abundant and Th. inermis and E. pacifica are supposedly allochtonous species which penetrate to the Okhotsk Sea through the Kuril Straits, so they are distributed mainly in the southern part of the Sea. Mean biomass and abundance of all species in the upper (0-50 m) and deeper (50-200 m) layers are calculated for each stage and size class in the daytime and nighttime, separately: most of them, including both adults and furcilias, concentrate mainly in the deeper layer and their night biomass is higher in both layers though about a half of animals raise to the sea surface at night. Only eggs, nauplii and calyptopes of euphausiids don’t change their abundance considerably between day and night, and most of them occupy the upper layer round the clock. Obviously, the increasing of late furcilias and adults in the deeper layer at night is caused by their diurnal migration from the layers below 200 m. Seasons of the highest abundance for early stages come in natural order that is a sign of their short duration.
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Kiss, Gabriella, Ferenc Molnar, and Ladislav A. Palinkaš. "Volcanic facies and hydrothermal processes in Triassic pillow basalts from the Darnó Unit, NE Hungary." Geologia Croatica 61, no. 2-3 (December 25, 2008): 385–94. http://dx.doi.org/10.4154/gc.2008.30.
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The Darnó Unit within the Zagorje-Mid-Transdanubian Megaunit is an allochtonous part of Dinarides in NE-Hungary and represents a relict of the Neotethyan accretionary complex. It contains blocks of submarine basalts of Triassic age in turbiditic sediments (olistrostrome) of Jurassic age. The lava clogged in the lime mud at the original site of volcanism and developed closely packed pillow, pillow fragment hyaloclastite breccia, and peperite facies. Interaction between the lava and the sea water produced mostly chloritic alteration of basalt and precipitation of hydrothermal calcite in amygdales, feeding channels of lava lobes and hyaloclastite breccia cements. Calcite is associated with chlorite, epidote, hematite and pyrite. Fluid inclusions in calcite infillings record conditions of fluid/rock interaction. Salinities of fluid inclusions (3.2 – 5.6 wt.% NaCl equiv. wt.%.) are close to the salinity of recent sea water and their homogenization temperatures in the range of 80 – 150oC. Fluid inclusion data support interpretation that volcanic facies represent rapidly cooled distal zones away from the submarine volcanic centre. This is also confirmed by the comparison to the volcanic and hydrothermal alteration facies of the submarine basalt lava-flow complex and associated pillow lava formation of Triassic age in the Hruškovec quarry in the Kalnik Mts., NW-Croatia. The obtained data contribute to understanding of the early history of Neotethyan evolution, i.e. dilemma about rifting or oceanization in Triassic time and offer new aspects of correlation between units of Dinaridic origin which had been displaced from their original setting by large scale Tertiary tectonic processes.
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Bouillon, S., T. Moens, and F. Dehairs. "Carbon sources supporting benthic mineralization in mangrove and adjacent seagrass sediments (Gazi Bay, Kenya)." Biogeosciences 1, no. 1 (October 28, 2004): 71–78. http://dx.doi.org/10.5194/bg-1-71-2004.
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Abstract. The origin of carbon substrates used by in situ sedimentary bacterial communities was investigated in an intertidal mangrove ecosystem and in adjacent seagrass beds in Gazi bay (Kenya) by δ13C analysis of bacteria-specific PLFA (phospholipid fatty acids) and bulk organic carbon. Export of mangrove-derived organic matter to the adjacent seagrass-covered bay was evident from sedimentary total organic carbon (TOC) and δ13CTOC data. PLFA δ13C data indicate that the substrate used by bacterial communities varied strongly and that exported mangrove carbon was a significant source for bacteria in the adjacent seagrass beds. Within the intertidal mangrove forest, bacterial PLFA at the surface layer (0-1cm) typically showed more enriched δ13C values than deeper (up to 10cm) sediment layers, suggesting a contribution from microphytobenthos and/or inwelled seagrass material. Under the simplifying assumption that seagrasses and mangroves are the dominant potential end-members, the estimated contribution of mangrove-derived carbon to benthic mineralization in the seagrass beds (16-74%) corresponds fairly well to the estimated contribution of mangrove C to the sedimentary organic matter pool (21-71%) across different seagrass sites. Based on the results of this study and a compilation of literature data, we suggest that trapping of allochtonous C is a common feature in seagrass beds and often represents a significant source of C for sediment bacteria - both in cases where seagrass C dominates the sediment TOC pool and in cases where external inputs are significant. Hence, it is likely that data on community respiration rates systematically overestimate the role of in situ mineralization as a fate of seagrass production.
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Civitarese, G., M. Gačić, M. Lipizer, and G. L. E. Borzelli. "On the impact of the Bimodal Oscillating System (BiOS) on the biogeochemistry and biology of the Adriatic and Ionian Seas (Eastern Mediterranean)." Biogeosciences Discussions 7, no. 5 (September 14, 2010): 6971–95. http://dx.doi.org/10.5194/bgd-7-6971-2010.
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Abstract. Analysis of 20-year time-series of the vertically averaged salinity and nutrient data in the South Adriatic shows that the two parameters are subject to strong decadal variability. In addition, nutrient and salinity variations are out of phase. Nutrients in the Ionian and in the Adriatic vary in parallel except that often the nutrient content in the Adriatic is lower than in the Ionian, a fact that has been attributed to primary producer consumption following the winter convective mixing. Horizontal distribution of the nitracline depth in the Ionian suggests that nutrient content in the Adriatic is a function of the circulation pattern in the Ionian that wells up or wells down the nitracline: cyclonic circulation causes a downwelling of the nitracline along the borders of the Northern Ionian Gyre (NIG) and a decrease in the nutrient content of the water flowing into the Adriatic across the Otranto Strait, and vice versa. The circulation variations are due to the Bimodal Oscillating System, i.e. the feedback mechanism between the Adriatic and Ionian. Inversion of the sense of the NIG results in the advection of Modified Atlantic Water or of the Levantine/Eastern Mediterranean (EMed) waters in the Adriatic. Here, we show that the presence of allochtonous organisms from Atlantic/Western Mediterranean (WMed) and EMed/temperate zone in the Adriatic are concomitant with the anticyclonic and cyclonic circulations, respectively, of the NIG. As a consequence of the NIG inversions, in the Ionian, this highly oligotrophic zone shows annual blooms in its central area only during cyclonic circulation. On the basis of the results presented, a revision of the theory of Adriatic ingressions formulated in the early 1950s is proposed.
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Nadtochy, Victoria V., and Yury I. Zuenko. "Mechanisms of subtropical plankton transport into the coastal waters of southern Primorye, a case of Paracalanus parvus." Izvestiya TINRO 184, no. 1 (March 30, 2016): 241–52. http://dx.doi.org/10.26428/1606-9919-2016-184-241-252.
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Results of long-term studies of zooplankton species in the Amur Bay (Japan Sea) are analyzed. Two seasonal «waves» of the allochtonous species are defined: the first in the early summer that is formed mainly by inter-zonal copepods spawning in the deep layers ( Metridia pacifica , Neocalanus plumchrus, Calanus glacialis ) and the second in the late summer that is represented by warm-water copepods of subtropical origin ( Calanus pacificus and Paracalanus parvus ) obviously transported from the southern Japan Sea by currents. The latter species is able to dominate in the zooplankton community of coastal waters in the early-autumn season. Variations of this mass species abundance in the Amur Bay under changes of wind-driven upwelling/downwelling circulation are investigated using an empirical advective model of its cross-shelf transport. There is found that strong summer southern on-shore winds (summer monsoon) are favourable for its high abundance but in these conditions it is transported toward the coast by the deep compensatory flow developed only after the summer monsoon change to the winter monsoon with opposite direction; that’s why the high abundance is observed in autumn, in September-October. In the years with weak summer monsoon the species is transported to the bay in mass by the surface on-shore wind-driven flow earlier, in August, but its number decreases after the monsoon change, so the maximum of abundance is not high. Patterns of the transport by cross-shelf currents depend supposedly on the depth of plankton concentration. Recent strengthening of summer monsoon causes heightening of P. parvus abundance in the coastal waters at southern Primorye, up to extreme high values in 2013, but climatic trend of the summer monsoon intensity is negative, so decreasing of this species transport toward Primorye coast and its abundance in the coastal waters, as the Amur Bay, can be expected in the nearest future.
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Zuenko, Yury I., and Eugene O. Basyuk. "Impact of changing oceanographic conditions on species composition and abundance of zooplankton on the fishing grounds at Cape Navarin and their importance for the Russian pollock fishery in the Bering Sea." Izvestiya TINRO 189, no. 2 (June 30, 2017): 103–20. http://dx.doi.org/10.26428/1606-9919-2017-189-103-120.
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Seasonal and interannual variability of zooplankton in the area at Cape Navarin are considered on the base of long-term surveys. This area is the main fishing grounds for Russian pollock fishery in the Bering Sea. Species composition of zooplankton changes cardinally during the feeding period: large-size copepods prevail in summer, but euphausiids, mainly the krill Thysanoessa inermis - in autumn. Year-to-year changes of the zooplankton abundance are species-specific and driven by different environmental factors. The water circulation is crucially important for such allochtonous species as krill by transporting them from the spawning areas. Advection either from the south, i.e. from the continental slope (till 2006), or from the east and west, i.e. from the shelf (in 2007-2014), was observed in the last two decades that corresponded to replacing of relatively warm oceanographic regime by relatively cold regime and could be traced by dynamics of the ice cover and the cold water pool area on the eastern Bering Sea shelf. The advection from the slope provides the krill transport to the area at Cape Navarin, but conditions of the cold regime limit the transport. From the other hand, the cold oceanographic regime is favorable for reproduction of many zooplankton species, including krill, because of higher primary productivity. As the result, the krill and some other mass zooplankton species have a bell-shape dependence of their abundance on water temperature: they have the maximal biomass in relatively warm years within the cold periods and in relatively cold years within the warm periods. In the years with severe winters, the pollock starts its back migration early, in August-September because of seasonal depletion of copepods and lack of krill, while the years with warm winters are also unfavorable for long feeding of pollock in the Navarin area because of low abundance of many zooplankton species. «Moderate» conditions are optimal for long feeding of pollock in this area, when the Russian fishery continues here longer, till November-December, with the annual landings > 500,000 t (as in 1996-1999, 2001, 2007-2008).
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Gay, Aurélien, Thibault Cavailhès, Dominique Grauls, Bruno Marsset, and Tania Marsset. "Repeated fluid expulsions during events of rapid sea-level rise in the Gulf of Lion, western Mediterranean Sea." Bulletin de la Société géologique de France 188, no. 4 (2017): 24. http://dx.doi.org/10.1051/bsgf/2017190.
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Based on a High-Resolution 3D seismic block acquired in the Gulf of Lion in 2004–2005 we investigated fluid pipes and pockmarks on the top of the interfluve between the Hérault canyon and the Bourcart canyon both created by turbidity currents and gravity flows from the shelf to the deep basin in the north-western Mediterranean Sea. Combining the geometry of the potential fluid pipes with the induced deformation of surrounding sediments leads then to the ability to differentiate between potential fluid sources (root vs source) and to better estimate the triggering mechanisms (allochtonous vs. autochtonous cause). We linked together a set of derived attributes, such as Chaos and RMS amplitude, to a 3D description of pipes along which fluids may migrate. As previously shown in other basins, the induced deformation, creating cone in cone or V-shaped structures, may develop in response to the fluid pipe propagation in unconsolidated sediments in the near surface. The level at the top of a cone structure is diachronous. It means that stratigraphic levels over this surface are deformed at the end of the migration. They collapse forming a depression called a pockmark. These pipes are the result of repeated cycles of fluid expulsion that might be correlated with rapid sea-level rise instead of sediment loading. The most recent event (MIS 2.2 stage) has led to the formation of a pockmark on the modern seafloor. It has been used as a reference for calculating the effect of a rapid sea-level rise on fluid expulsion. As all physical and geometrical parameters are constrained, we were able to define that a + 34 m of sea level rise may account for triggering fluid expulsion from a very shallow silty-sandy layer at 9 m below seafloor since the last glacial stage. This value is consistent with a sea level rise of about 102 m during this period. This study shows that the episodic nature of fluid release resulted from hydromechanical processes during sea-level rise due to the interactivity between high pressure regimes and principal in situ stresses.
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Pujo-Pay, M., P. Conan, L. Oriol, V. Cornet-Barthaux, C. Falco, J. F. Ghiglione, C. Goyet, T. Moutin, and L. Prieur. "Integrated survey of elemental stoichiometry (C, N, P) from the western to eastern Mediterranean Sea." Biogeosciences 8, no. 4 (April 8, 2011): 883–99. http://dx.doi.org/10.5194/bg-8-883-2011.
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Abstract. This paper provides an extensive vertical and longitudinal description of the biogeochemistry along an East-West transect of 3000 km across the Mediterranean Sea during summer 2008 (BOUM cruise). During this period of strong stratification, the distribution of nutrients, particulate and dissolved organic carbon (DOC), nitrogen (DON) and phosphorus (DOP) were examined to produce a detailed spatial and vertically extended description of the elemental stoichiometry of the Mediterranean Sea. Surface waters were depleted in nutrients and the thickness of this depleted layer increased towards the East from about 10 m in the Gulf of Lion to more than 100 m in the Levantine basin, with the phosphacline deepening to a greater extent than that for corresponding nitracline and thermocline depths. We used the minimum oxygen concentration through the water column in combination with 2 fixed concentrations of dissolved oxygen to distinguish an intermediate layer (Mineralization Layer; ML) from surface (Biogenic Layer; BL), and deep layers (DL). Whilst each layer was represented by different water masses, this approach allowed us to propose a schematic box-plot representation of the biogeochemical functioning of the two Mediterranean basins. Despite the increasing oligotrophic nature and the degree of P-depletion along the West to East gradient strong similarities were encountered between eastern and western ecosystems. Within the BL, the C:N:P ratios in all pools largely exceeded the Redfield ratios, but surprisingly, the nitrate vs. phosphate ratios in the ML and DL tended towards the canonical Redfield values in both basins. A change in particulate matter composition has been identified by a C increase relative to N and P along the whole water column in the western basin and between BL and ML in the eastern one. Our data showed a noticeable stability of the DOC:DON ratio (12–13) throughout the Mediterranean Sea. This is in good agreement with a P-limitation of microbial activities but in contradiction of the accepted concept that N is recycled faster than C. The western and eastern basins had similar or close biological functioning. Differences come from variability in the allochtonous nutrient sources in terms of quantity and quality, and to the specific hydrodynamic features of the Mediterranean basins.
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Gomez, Fernando J., and Ricardo A. Astini. "Sedimentology and paleoenvironments of the La Laja Formation (Cambrian), Quebrada La Laja, Sierra Chica de Zonda, San Juan, Argentina." Andean Geology 33, no. 1 (June 30, 2010): 19. http://dx.doi.org/10.5027/andgeov33n1-a02.
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The La Laja Formation is a key unit regarding the hypothesis of the Argentine Precordillera as a Laurentia-derived allochtonous terrane in the south central Andes. Together with the Cerro Totora Formation it comprises the oldest unit exposed at the base of the Lower Paleozoic carbonate platform of the Precordillera. According to previous work these units record the rifting-drifting history of this terrane exotic to Gondwana. The La Laja Formation contrasts with the rest of the overlying units of the Cambro-Ordovician carbonate platform by being partly mixed carbonate-siliciclastic. A detailed facies analysis of the five recognized members in the reference section at Quebrada La Laja (Sierra Chica de Zonda, San Juan Province) allow the recognition of 19 microfacies grouped into four main environmentally significant associations: 1) a storm-influenced, deep subtidal environment with variable influx of fine siliciclastic sediments; 2) shallow subtidal, 3) mixed shallow subtidal and 4) shallow subtidal to intertidal occasionally with well developed high-frequency tidal flat cycles. No deeper basinal or slope facies were found. In contrast, the unit largely records shallow-marine facies with some evidence of subaerial exposure. Medium to coarse, calcareous, feldspar-rich sandstones and sandy limestones characterize the El Estero Member. The base of the Soldano Member shows profuse development of cyclicity with capping oolitic shoals. This member and the upper Juan Pobre Member contain deeper subtidal intervals, below the storm weather wave base, with high percentages of fine terrigenous material represented by shaly marls and nodular limestones. Skeletal-rich and oolite-rich storm beds are recorded within them. Relative shallowing to subaerial environments recorded within the Rivadavia and Las Torres members, with the development of ribbon limestones, intraclastic rudstones, microkarstic surfaces and exposure breccias. Herringbone cross-bedded oolite shoals are common at the top of the uppermost Las Torres Member. The transition into the overlying Zonda Formation is represented by an abrupt rearrangement of the depositional systems and development of meter-scale microbial-rich peritidal cycles. Several orders of superposed cyclicity are recorded within the La Laja Formation. Larger-scale cycles ('Grand Cycles') are inferred from alternating members with important amounts of siliciclastics, whereas meter-scale cycles indicate higher frequency superposed mechanisms. Altogether these show a complex depositional history linking environmental and tectono-eustatic signatures.
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Koroteev, Viktor A., Viktor M. Necheukhin, Artur A. Krasnobaev, and Elena N. Volchek. "Terrains of the main geodynamical types in the structures of Ural-Timan areal and the Eurasia North-Eastern segment." LITOSFERA, no. 6 (December 28, 2018): 779–96. http://dx.doi.org/10.24930/1681-9004-2018-18-6-779-796.
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Subject of study. Different points of view on the concept of structures of the terrain type and their role in the addition of orogenic belts are considered. Materials and methods. We used our own research and analysis of the latest publications about the Ural-Timan region and the Pacific belt, on the territory of the Northeast segment of Eurasia, as well as currently known isotope radiometric data. It was used also the result of geophysical seismotectonic and paleomagnetic explorations. Results. It has been established that in the composition of the Ural-Timan structural area, along with the Proterozoic and Paleozoic associations of the orogenic belts and the Riphean sedimentary series of protrusions of the Russian Plate, structural formations that correspond to the terrain of the continental crust take part. They are the most characteristic for the Ural orogenic belt, which belongs to the group of epiokean-type belts, associated with the transformation of ocean basins with the active participation of accretion and collision processes. The parametric features of these terrains include the ancient age characteristics of terrain rocks, their position in the belt structure, as well as the presence of relics of subhorizontal layered structural elements. The discordant blocks of migmatites, gneisses and other metamorphic rocks of Precambrian age, which make up the terrains, was the basis for the introduction of the term “terranes of the ancient continental crust”. By connection with the source, exotic and endemic, and simple and complex terrains are distinguished by structure. The geodynamics of including terrains of the ancient continental crust into the structure of orogenic belts is associated with horizontal movements of fragments of the ancient lithosphere in oceanic paleobasins to the periphery of the Russian Plate and their localization in belt structures. The formation of these terrains in the structures of the orogenic belts is completed by the formation of the intra-terrain massifs of granitoids and belts of volcanic-intrusive series. Supporters of a different methodology, dominant among researchers of the Pacific Belt of the Northeast Segment of Eurasia, refer to terrains all the structural elements that perform orogenic belts, because they believe that they have undergone horizontal movements and are in allochtonous occurrence. Conclusions. It has been established that in different geological provinces the term terrain has its own characteristics. This was the basis for the selection of two geodynamic types of terrains.
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Friis, Joseph, and Alexandra Arellano. "La réconciliation à travers les séjours d’immersion à Kitcisakik." Articles, no. 19 (June 4, 2021): 43–66. http://dx.doi.org/10.7202/1077729ar.
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Depuis 2010, les Anicinapek de Kitcisakik ont mis sur pied une initiative de séjours de sensibilisation, où des voyages éducatifs et d’immersion se sont développés, principalement avec des groupes scolaires et universitaires allochtones. Ces séjours sont devenus des occasions privilégiées de dialogue qui favorisent non seulement la transmission intergénérationnelle et la distinction épistémologique du savoir local, mais aussi la compréhension de la situation sociohistorique et coloniale des peuples autochtones. Rejetant assidument le système de réserve et occupant leur terre ancestrale sans réelles assises juridiques à la lumière du droit positif canadien, les Anicinapek invitent des Allochtones à célébrer leur culture en s’imprégnant du lien à la terre, établissant ainsi la centralité des luttes territoriales dans les processus de réconciliation. Ancrée dans une approche théorique du « colonialisme de peuplement » (« settler-colonialism »), cette réflexion explore le cas particulier de Kitcisakik dans le contexte des séjours d’immersion, invitant les étudiants allochtones à partager leur expérience de sensibilisation. À travers un récit situant les luttes territoriales, le regard des Anicinapek et des étudiants allochtones est mis de l’avant. Les séjours d’immersion offerts par la communauté de Kitcisakik incarnent une ouverture à l’Autre qui offre une expérience privilégiée de réconciliation autocritique.
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Малахов, Владимир. "Immigrants as social agents: allochtones and autochtones." Полис. Политические исследования (Polis. Political Studies), no. 1 (January 21, 2015): 111–25. http://dx.doi.org/10.17976/jpps/2015.01.09.
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Uzel, Jean-Philippe. "L’autochtonie dans l’art actuel québécois. Une question partagée." Globe 17, no. 1 (February 12, 2015): 33–57. http://dx.doi.org/10.7202/1028632ar.
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À l’heure où les artistes visuels autochtones (Premières Nations, Inuits et Métis) se détachent de la « politique de l’identité », les artistes allochtones (d’ascendance européenne) font de plus en plus souvent référence dans leurs oeuvres à des questions en lien avec l’autochtonie. Cet article examine certaines de ces questions en établissant trois dialogues entre le travail d’un artiste autochtone et d’un artiste allochtone vivant au Québec : l’exploitation industrielle des territoires autochtones dans le Nord du Québec, par l’Algonquine Nadia Myre et l’artiste d’origine suisse Thomas Kneubühler ; les nouvelles attitudes et comportements générés par la société d’hyperconsommation, par l’artiste laich-kwil-tach Sonny Assu et le collectif BGL ; les relations entre Autochtones et colons durant le régime colonial français, chez l’artiste innue Sonia Robertson et l’artiste montréalaise Cynthia Girard. Bien que l’autochtonie, à travers ces trois dialogues, apparaisse comme une question partagée par les artistes actuels autochtones et allochtones, à aucun moment il n’est possible d’établir une équivalence entre les uns et les autres. Alors que chez les artistes allochtones l’autochtonie est traitée comme un motif secondaire, passant parfois inaperçue aux yeux des critiques d’art, elle constitue toujours le thème central des artistes autochtones chez qui elle s’ancre dans le destin, souvent tragique, de leur communauté.
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Pascal, Michel, Olivier Lorvelec, Nicolas Barré, and Michel de Garine-Wichatitsky. "Espèces allochtones d’Esperitu Santo. Premiers résultats de l’expédition Santo 2006." Journal de la société des océanistes, no. 126-127 (December 15, 2008): 187–93. http://dx.doi.org/10.4000/jso.3962.
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Brion, Fabienne. "Une passion néerlandaise : la recherche sur la criminalité des allochtones." Hommes et Migrations 1241, no. 1 (2003): 66–77. http://dx.doi.org/10.3406/homig.2003.3949.
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Plumet, Patrick. "Matières premières allochtones et réseau spatial paléoesquimau en Ungava occidental, Arctique québécois." Géographie physique et Quaternaire 35, no. 1 (January 25, 2011): 5–17. http://dx.doi.org/10.7202/1000373ar.
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Contrairement à ce qui est observé dans la plupart des autres régions de l’Arctique oriental, une partie importante des matières premières lithiques utilisées par les Paléoesquimaux de la baie d’Ungava étaient allochtones. Parmi celles-ci, le quartzite originaire de Ramah (voir de BOUTRAY, 1981) et le quartz laiteux des environs de Maricourt-Wakeham et du lac Robert tenaient une place prépondérante pour les objets à fort indice de façonnage. La caractérisation des steatites par leurs teneurs en éléments des terres rares (voir ARCHAMBAULT, 1981) a permis de suggérer certains rapprochements entre contenants façonnés et carrières du Labrador et de la région de Wakeham. L’interprétation de ces données conduit à esquisser les grandes lignes d’un réseau spatial autrement indécelable et à suggérer que la mise en place du peuplement paléoesquimau de l’Ungava occidental a pu se faire à partir du Labrador contrairement à ce qui avait été proposé auparavant (PLUMET, 1977). De plus, en dépit d’obstacles géographiques apparemment plus grands vers l’est que vers l’ouest, les relations entre l’Ungava occidental et le Labrador septentrional se seraient maintenues tout au long du Paléoesquimau jusqu’à la fin du Dorsétien (vers 1500 après J.-C.) alors que les traces de relations avec l’Hudsonie, qui semble plus facile d’accès, sont encore très faibles.