Articles de revues : « Ancient Lower Northern Bengal »

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Kazarova, S. Y., et G. A. Novitskaya. « Ancient parks and gardens of Northern and Eastern India ». Journal of Native and Alien Plant Studies, n^o 1 (28 décembre 2021) : 110–18. http://dx.doi.org/10.37555/2707-3114.1.2021.247560.

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The 30 ancient gardens of Northern India were studied: 9 palace gardens, 13 memorial gardens (at tombs), 8 gardens of “royal rest”, and 2 ancient botanical gardens of West Bengal (East India) for 11 years (from 2008 to 2019). Brief information is given for each object: the year of the garden' s foundation, the size, historical objects on the territory of the park (garden), the presence of old-age trees and some tree species is noted; inaccessible and / or rarely visited ancient gardens are described in more detail (Mughal Gardens in Delhi, Yadavindra Gardens in Pinjor and others). A full description of the ancient gardens (parks) of India is given in the publications of the authors, a list of which is given.

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SINGH, O. P. « Thermodynamical characteristics of monsoon troposphere over the Bay of Bengal ». MAUSAM 50, n^o 3 (17 décembre 2021) : 251–56. http://dx.doi.org/10.54302/mausam.v50i3.1855.

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Thermodynamical characteristics of monsoon troposphere, especially the lower troposphere, over different regions of Bay of Bengal has been studied utilising the radiosonde data collected by Ocean Research Vessel (ORV) Sagar Kanya during the period 8 July-5 August, 1991. The results reveal the existence of low level inversions over the central and adjoining parts of southern Bay of Bengal between 13.4°-17.2°N and 84.5°- 90.0°E during July-August The lower troposphere upto 850 hPa appears to be absolutely stable over this region of Bay of Bengal. In total contrast, none of the ascents taken over the region north of 17.7°N showed any low level inversion. The lower troposphere over the northern Bay of Bengal where convection develops under favourable synoptic situations in monsoon, was found to be unstable. In July the low level inversion appears to extend far south (upto about 10.3°N) but gets disintegrated over the southern parts of Bay of Bengal with the advance of season. Many ascents over the northern and central Bay of Bengal have shown the occurrence of stable layers near 0° level. In the equatorial Bay of Bengal between 5°-10°N stable layers appear to exist near 400 hPa level and near 850-800 hPa level. The results seem to provide an insight into the pattern of convection over the Bay of Bengal during monsoon.

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Chakravarti, Ranabir. « Early Medieval Bengal and the Trade In Horses : a Note ». Journal of the Economic and Social History of the Orient 42, n^o 2 (1999) : 194–211. http://dx.doi.org/10.1163/1568520991446839.

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AbstractThis essay brings into focus a relatively neglected aspect of economic life in early medieval Bengal. Like many other parts of India, Bengal during ancient and early medieval times did not have any indigenous, good quality war horses. The emergence of Bengal as a regional political entity to reckon with during the early medieval times (c. AD 600 - 1300) must have increased the demand for war horses. The paper analyses the epigraphic accounts of the procurement of these indispensable war animals from northern and northwestern India by the rulers of early medieval Bengal. The Tabaqat-i-Nasiri of the thirteenth century gives an indication of the availablity of northeastern horses - probably Tibetan ones - in Bengal. Chinese accounts of the fifteenth century and some Arabic accounts of the invasions of the Deccan by the Delhi Sultante have been utilised here to suggest that early medieval Bengal not only received regular supplies of imported horses, but also witnessed the transportation of some of these war machines to the Deccan and China.

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Dey, Nayan, et Payel Das. « Coastal Vulnerability Assessment of Kanthi Coast, India by the Geospatial Technology ». Indonesian Journal of Social and Environmental Issues (IJSEI) 4, n^o 3 (30 décembre 2023) : 221–41. http://dx.doi.org/10.47540/ijsei.v4i3.910.

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Since ancient times, most of the world’s civilization flourished along the banks of rivers and the coastal region. So the coastal region plays a vital role for human economic activities as well as their livelihood. The Kanthi coast, the northernmost part of the North Circus coast of India stretches in West Bengal and northern Odisha. The 45 km stretched coast land is associated with a dense population and faces the tropical cyclone emerging from the Bay of Bengal. The prime objective of the paper is to assess the coastal vulnerability of the study area. With the help of several indicators, viz. shoreline change rate, rate of sea level change, slope of the beach, wave height, tidal range, regional elevation, geomorphic features, sediment properties, coastal regulation zone (CRZ) violation ratio, the research work assess the Coastal Vulnerability Zone (CVZ) of the Kanthi Coastal region. The weightage sum method and Coastal Vulnerability Index (CVI) are being used. From this research work, it has been revealed that the western segment especially, Digha and Shankarpur are experiencing a high vulnerability situation.

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Raj, Harsh, Ravi Bhushan, M. Muruganantham, Romi Nambiar et Ankur J. Dabhi. « MARINE RESERVOIR AGE CORRECTION FOR THE ANDAMAN BASIN ». Radiocarbon 62, n^o 5 (1 septembre 2020) : 1339–47. http://dx.doi.org/10.1017/rdc.2020.91.

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ABSTRACTMarine reservoir age is an important component for correction in radiocarbon (14C) dating of marine and coastal samples. 14C concentration in pre-bomb marine samples of known age are used to derive marine reservoir age of a region. Annually banded coral from Landfall island in the northern Andaman has been analyzed for its 14C concentration during the pre-bomb period 1948–1951. 14C age and reservoir effect (∆R) are reported for these pre-bomb coral samples from the northern Andaman region. The mean 14C age of 331 ± 61 yr BP was obtained for the period 1948–1951 with an average reservoir age correction of –138 ± 61 yr. This reservoir age correction is lowest reported from the northern Indian Ocean. ∆R value of the northern Andaman and the Bay of Bengal appears lower than that of southern Andaman. The ∆R values obtained using mollusk shells and coral from the Andaman region shows large variability. The lower reservoir age correction for the Landfall Island situated in the northern part of the Andaman archipelago, could result due to freshwater flux and reduced upwelling in the region.

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Shith, Arijit, Srikanta Padhan, Avilash Mohapatra et Sanjana Agrawal. « Eastern India's response to the pandemic : a comparative assessment of West Bengal, Bihar, and Odisha ». International Journal Of Community Medicine And Public Health 11, n^o 1 (30 décembre 2023) : 248–51. http://dx.doi.org/10.18203/2394-6040.ijcmph20234133.

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Background: The three eastern states of India (Odisha, Bihar, and West Bengal) share common borders with similar cultural and socio-demographic characteristics due to historical ties. In the recent past, these states witnessed large-scale return migration of workers, leading to increasing numbers of COVID-19 cases. Despite the increasing number of cases, the testing capacity in Odisha, Bihar, and West Bengal is significantly lower compared to the testing capacities in the western, southern, and northern regions. Methods: This study utilized a nine-month retrospective longitudinal design, focusing on the COVID-19 situation and healthcare facilities in Odisha, West Bengal, and Bihar from May 2020 to January 2021. Data were extracted from various Government and research institution websites, and descriptive analyses employed bar and line diagrams. Results: Odisha and Bihar show declining COVID-19 cases, deaths, and test positivity rates, while West Bengal is on the rise. Testing rates are consistently increasing in all three states. West Bengal has the highest doctors per million, Odisha has the most nurses per million, and more pharmacists are registered in West Bengal. In health infrastructure, Odisha has COVID-19 special hospital testing centers, while West Bengal leads in hospital beds and ICU beds. Conclusions: The burden of COVID-19 infection in India was heterogeneous, with evidence of high transmission in the eastern, northeast, western, and southern regions. The study findings will be helpful in making informed decisions about the current state-wise health status in eastern India.

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Sahu, RajeshKumar, Bhishma Tyagi, NareshKrishna Vissa et Mrutyunjay Mohapatra. « Pre-monsoon Thunderstorm Season Climatology of Convective Available Potential Energy (CAPE) and Convective Inhibition (CIN) over Eastern India ». MAUSAM 73, n^o 3 (1 juillet 2022) : 565–86. http://dx.doi.org/10.54302/mausam.v73i3.1247.

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The present work analyses climatological variations of Convective Available Potential Energy (CAPE) and Convective Inhibition (CIN) over the eastern India (Odisha, West Bengal and Jharkhand) during the pre-monsoon season, where thunderstorms are frequent and disastrous. The work utilises European Centre for Medium-Range Weather Forecast (ECMWF) reanalysis data: ERA-5 for 1987-2016, supplemented with information about thunderstorm occurrences over the region from India Meteorological Department (IMD). The CAPE and CIN values can differentiate thunderstorm days (TD) from non-thunderstorm days (NTD), with favourable conditions of convective weather on days of thunderstorms over the region, evident by CAPE and CIN. The coastal areas of Odisha and West Bengal, along with the Jharkhand bordering the northern West Bengal region, have higher CAPE and lower CIN values. The trend analysis of CAPE and CIN has been performed using the non-parametric Mann-Kendall test, which shows an apparent transformation of indices over time for different regions of states for TD and NTD. CAPE shows an increasing trend over the coastal districts of Odisha and West Bengal during TD and for the whole of West Bengal during 12 UTC NTD. The NTD cases show a decreasing trend over Odisha (both 00 and 12 UTC) and 00 UTC over West Bengal. CIN shows an increasing trend for TD and decreasing trend for NTD over whole Odisha, whereas, for West Bengal, trends are positive for coastal regions during TD and negative on the entire state during NTD. For Jharkhand, both the CAPE and CIN values show an increasing trend over the state during NTD, whereas for TD, both increasing/decreasing trends are visible. The analysis complements the observations of thunderstorm occurrence over the region to understand areas with higher potential of thunderstorm occurrence during pre-monsoon season.

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Boltryk, Yu V., et O. V. Kariaka. « THE OLDEST TRANSPORT ARTERY OF SCYTHIA (Lower Hypanis — middle course of Borysthenes Track) ». Archaeology and Early History of Ukraine 47, n^o 2 (15 juin 2023) : 202–14. http://dx.doi.org/10.37445/adiu.2023.02.14.

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The article examines the connection between the archaeological sites of the pre-Scythian and Scythian times and the key watersheds of Right Bank Ukraine, as routes of potential overland communications that used to move goods in ancient times. One of the impetuses for turning to this topic was the discovery of four archaic amphorae (one whole from Klazomenai, others from Lesbos) at the recently discovered Khotynets hillfort in Poland, which is located in the extreme west of the country of the Early Iron Age hillforts of southern Eastern Europe. These finds of amphora containers in the area of Vyshnia and San valleys convincingly testify that trade caravans could reach this distant region from the Black Sea coast using only the land route. For its time, land communications were optimal, as they provided relatively reliable movement with a heavy load, along a path practically devoid of sharp descents and ascents. Key attention in the article is given to one of the most ancient routes that connected the northern coast of the Black Sea with settlement structures in the Middle Dnieper region. The extreme points in this transport system were pre-Scythian hillforts — Dykii Sad located at the confluence of the Ingul and Southern Bug rivers and its potential northern partner Subotivske in the Tiasmin basin. During the Scythian rule in the Black Sea steppes, this route continued to be actively used. However, over time, the final trade terminals changed, and the route of trade caravans remained. Merchants from Olbia and the harbors of the northern coast of the Black Sea used the eastern edge of the Southern Bug basin as a reliable route to the fortified settlement structures of the forest-steppe Right Bank, among them Matronynske and the Trakhtemyrivske hillforts. Given the shallow depths near the coast of Olbia, the authors consider the harbour of the little-explored ancient hillfort of Hlyboka Prystan as a likely place for unloading sea vessels with a deep draft. From this harbour opened a convenient way to the hillforts of the Forest Steppe, just using the oldest transport artery of Scythia.

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Lim, Dongmin. « Exploring a New Methodology for Studying Korean Ancient History Using Network Analysis : Focusing on negotiation data from the Eastern Jin and Sixteen Kingdoms to the Song and Northern Wei period ». International Journal of Korean History 28, n^o 2 (31 août 2023) : 219–58. http://dx.doi.org/10.22372/ijkh.2023.28.2.219.

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Network analysis is a methodology that helps understand complex phenomena by visualizing member interactions. In the context of Eastern Jin, Sixteen Kingdoms, Song, Northern Wei period, network analysis can shed light on the position of Paekche and Koguryŏ by analyzing negotiation networks. While existing studies have focused on negotiations between these states and China, few have visualized the entire negotiation network or compared the positions of Paekche and Koguryŏ within the broader East Asian network. This paper explores the network analysis methodology for ancient East Asian negotiation data and conducts a pilot analysis of specific periods.</br>The methodology for applying network analysis to ancient history involves several steps, including evaluating its suitability, quantifying the data, verifying data reliability, and analyzing and visualizing the data. Limitations of using network analysis to study ancient history include obtaining sufficient data and verifying data reliability. Ancient East Asian negotiation data is relatively more abundant than other records, making it a good candidate for network analysis. However, because negotiation data is recorded from the perspective of various actors, it is essential to verify the reliability of the data by ancient history researchers.</br>This paper theoretically analyzes the negotiation data of the Eastern Jin, Sixteen Kingdoms, Song, and Northern Wei periods. The negotiation network analysis reveals that Eastern Jin is the most centralized country, with Koguryŏ actively engaging in negotiations and Paekche focusing on diplomacy with Eastern Jin. The centrality analysis on the negotiation frequency data during Song and Northern Wei period shows that the Song and Northern Wei had the highest centrality in negotiation frequency among 28 countries, with Koguryŏ, Tuyuhun, and Paekche also prominent. The negotiation route analysis reveals the flow of information, with the Song having the highest betweenness centrality, Koguryŏ serving as a conduit to Shilla, and Paekche controlling the route to Mahan, Kaya, and Wa. Paekche plays a crucial role as a conduit between various regions, despite having lower centrality than Koguryŏ.</br>In conclusion, this paper explored the methodology of applying network analysis to ancient East Asian negotiation data and attempted to understand the structural structure of ancient East Asian negotiation networks by analyzing negotiation data from a specific time period.

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Yasmin, Dilruba, Md Kawser Ahmed, Md Moniruzzaman Khondkar, Seema Rani, Abdullah Al Mamun Siddiqui, Ahmad Al Karim et Makidul Islam Khan. « Species Composition, Abundance and Diversity of Phytoplankton Inhabiting around the Swatch-of-No-Ground of Northern Bay of Bengal ». Dhaka University Journal of Earth and Environmental Sciences 10, n^o 1 (31 octobre 2021) : 11–21. http://dx.doi.org/10.3329/dujees.v10i1.56276.

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This study aimed to estimate the abundance and diversity of phytoplankton at different depth of water columns in Northern Bay of Bengal, Bangladesh. Samples were collected from 24 stations using Niskin water sampler from 0 to 250 m depths in four different cruises from January, 2017 to January, 2018 with the collaboration of Bangladesh Navy. Before sample identification, the samples were subjected to preservation using Lugol’s solution. A total of 70 phytoplankton species were identified of which Bacillariophyceae, Dinophyceae and Chlorophyceae covered 74.28%, 21.42% and 4.28% of species, respectively. The average phytoplankton density was 12,238±7,281 cells/L. Results showed phytoplankton abundance and distribution was comparatively lower in higher water depth than surface water. The highest phytoplankton abundance (39,342 cells/L) was recorded at surface water and the lowest abundance (16 cells/L) was observed in 200 m depth. Phytoplankton abundances significantly reduced at higher water depths (p < 0.05) which might be associated with higher light and nutrients availability at surface water and mixed layer depth. However, there was weak negative correlation since r = - 0.33. Phytoplankton abundance was also varied from station to station at similar water depth. Species richness was the highest in surface water. In this study, estimated Shannon-Wiener index was 0.58 that represented phytoplankton was moderately distributed at surface water than higher depth. The findings of the present study might be used as a baseline study to understand the phytoplankton community of the Northern Bay of Bengal which directly and/or indirectly help to manage existing ecosystem and sustainable fisheries of the Bay of Bengal. The Dhaka University Journal of Earth and Environmental Sciences, Vol. 10(1), 2021, P 11-21

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MOHAPATRA, ANIL, DIPANJAN RAY, SWARUP R. MOHANTY et SUBHRENDU SEKHAR MISHRA. « Ophichthus johnmccoskeri sp. nov. (Anguilliformes : Ophichthidae) : a new snake eel from Indian waters, Bay of Bengal ». Zootaxa 4462, n^o 2 (27 août 2018) : 251. http://dx.doi.org/10.11646/zootaxa.4462.2.7.

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A new species of snake eel (Anguilliformes: Ophichthidae: Ophichthinae), Ophichthus johnmccoskeri sp. nov., is described from three specimens collected from the northern part of the Bay of Bengal, India. Ophichthus johnmccoskeri sp. nov. is distinguished from its congeners by having the dorsal-fin origin well behind the pectoral-fin tips, by tooth pattern (lower jaw with a single row anteriorly followed by biserial teeth on anterior sides and tri-serial teeth posteriorly), and vertebral count (24 predorsal, 51–52 preanal, and 156–158 total).The new species has a single barbel between the anterior and posterior nostrils; vomerine teeth biserial anteriorly, multi to triserial and biserial medially and in a single row posteriorly; maxillary teeth biserial anteriorly and triserial posteriorly; tip of the lower jaw toothless; and tail length 1.6 times in total length.

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Islam, MD Monirul. « An Analysis of Spatial Patterns of Disabled Persons in West Bengal ». IJDS Indonesian Journal of Disability Studies 4, n^o 2 (5 décembre 2017) : 137–45. http://dx.doi.org/10.21776/ub.ijds.2017.4.2.6.

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In this paper an attempt has been made to observe the spatial patterns of disabled persons by sex and residence in and across the districts of West Bengal. The research paper is exclusively based on secondary sources of data which have been taken from Census of India publications, New Delhi. Advanced statistical techniques have been used to analyze the data. Apart from, advanced cartographic techniques and GIS-MapInfo has also been used to visual representation of the data. The study reveals that disabled persons are highly concentrated in southern part of the state while, central part and a little area of northern part have the lower concentration. There is an enormous regional variation in the distributional patterns of male-female and rural-urban areas of the state. The study also examined the probable association between disability and selected socio-economic variables and it is observed that several variables are significantly associated with disability.

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Chowdhury, Soham. « MIGRATORY WETLAND BIRDS DIVERSITY IN LOWER CHOTA NAGPUR PLATEAU WITH SPECIAL REFERENCE TO PURULIA DISTRICT, WEST BENGAL, INDIA ». International Journal of Advanced Research 8, n^o 10 (31 octobre 2020) : 357–67. http://dx.doi.org/10.21474/ijar01/11863.

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Lower Chota Nagpur Plateau has several large and small water bodies having diverse aquatic flora and fauna. These wetlands not only provide suitable habitat for resident and as well as migratory avian species but also contribute much to the biodiversity. The present study deals with the diversity, abundance and variations of avian migratory species at wetlands of Purulia district. The study reflects that there are 43 migratory bird species in number in these wetland regions belonging to 8 orders and 12 families. Red-crested Pochard, Tufted Duck, Lesser Whistling Duck, Northern Pintail, Gadwall, Eurasian Wigeon, Common Coot etc. are found in large number in winter season in these wetlands.

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Zhang, Zhichao, Yuwang Wang, Dedong Li et Chunkit Lai. « Lithospheric Architecture and Metallogenesis in Liaodong Peninsula, North China Craton : Insights from Zircon Hf-Nd Isotope Mapping ». Minerals 9, n^o 3 (14 mars 2019) : 179. http://dx.doi.org/10.3390/min9030179.

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The Liaodong Peninsula is an important mineral province in northern China. Elucidating its lithospheric architecture and structural evolution is important for gold metallogenic research and exploration in the region. In this study, Hf-Nd isotope maps from magmatic rocks are constructed and compared to geological maps to correlate isotopic signatures with geological features. It is found that gold deposits of different age periods in Liaodong are located in areas with specific εHf(t) and εNd ranges (Triassic: from −8 to −4 and from −12 to −8, Jurassic: from −22 to −8 and from −14 to −8, Cretaceous: from −12 to −10 and from −22 to −20), respectively. This may reflect that when the Paleo-Pacific plate was subducted beneath the North China Craton, the magma was derived from the juvenile lower crust and the ancient lower crust, and formed the low-to-moderate hydrothermal Au-(Ag) and Pb-Zn deposits in the Triassic. In the Jurassic, continued subduction may have led to lithospheric thickening. Subsequently, the magma from the ancient lower crust upwelled and formed low-to-moderate hydrothermal Au deposits and porphyry Mo deposits. In the Cretaceous, crustal delamination may have taken place. The magma from the ancient lower crust upwelled and formed various low-to-moderate hydrothermal Au deposits.

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Georgiev, Svetoslav, Gatien L. F. Morin, Lora Bidzhova et Nikola Botoucharov. « Depositional conditions for Lower–Middle Jurassic sedimentary rocks from Northern Bulgaria inferred from whole-rock elemental composition ». Review of the Bulgarian Geological Society 83, n^o 3 (décembre 2022) : 81–84. http://dx.doi.org/10.52215/rev.bgs.2022.83.3.81.

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The Lower–Middle Jurassic sedimentary rocks from Northern Bulgaria represent important stratigraphic markers and a potential source for oil and gas accumulation. Here, we present preliminary major and trace element results for 22 sedimentary rock samples from the Bachiishte, Ozirovo, and Etropole Formations collected from the Balkanides and the Moesian Platform in Central-northern and Northwestern Bulgaria. The three studied formations have largely similar geochemical characteristics. The application of established geochemical proxies and comparison with recent and ancient sediments suggests that the samples were deposited in a shallow, high-energy environment with no water restriction. Eroding mafic to intermediate lithologies provided the sediment into the submerging Moesian Platform. Most redox-sensitive geochemical parameters suggest an overall oxygenated environment during sediment deposition, although specific samples show evidence for periodically dysoxic or anoxic water column conditions.

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A. B. Hejran, G. E. Sapayeva et K. ZH. Abdibekova. « "THE EFFECT OF ANCIENT GEOLOGICAL PERIODS IN BIOLOGY" ». Bulletin of Toraighyrov University. Chemistry & ; Biology series, n^o 1.2023 (29 mars 2023) : 69–83. http://dx.doi.org/10.48081/xvpf4854.

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"At the end of the 19th century and the beginning of the 20th century, extensive works began in the world for the construction of railways, and for these works, the previous biography of land is necessary. William Smith was the first scientist. The rocks found in the Somerset region from the lower layers of the earth and belong to the Jurassic period (20–144 million years ago). He compared the rocks of the coastal areas of the northern seas and using these rocks, he drew a map of the past periods of the earth in England. Even so far, the stones that came from the lower layers of the earth represented its place, that is, by using those stones, William Smith not only made a map of the past of the earth, but also a map of the lower layers of the earth. This map has a special place in the knowledge of modern geology it helps us to create a table of the past periods. From the information contained in this map, we can see the underground layers and their contents, iron, coal, etc. even if it is in the middle of the ocean. Fossils are very valuable to us. By using fossils, humans can identify the living creatures of the past times and get to know their ways of life. It can also be done by using fossils to divide the age table of the earth into cycles first and then the cycles are divided into periods. For this reason, the previous age table is first divided into periods and then the periods are divided into periods. 1. Upper Carboniferous Period; 2. Lower Carboniferous Period; 3. Middle Jurassic Period; 4. Jurassic Period and 5. Triassic Period. Keywords: Period, fossils, Evolutionary modeling, extinction, Biodiversity and organisms. "

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Kumar, S., R. Ramesh, N. B. Bhosle, S. Sardesai et M. S. Sheshshayee. « Natural isotopic composition of nitrogen in suspended particulate matter in the Bay of Bengal ». Biogeosciences 1, n^o 1 (14 octobre 2004) : 63–70. http://dx.doi.org/10.5194/bg-1-63-2004.

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Abstract. We present the first measurement of nitrogen isotopic composition (δ15N) in suspended particulate matter (SPM) of the surface Bay of Bengal (BOB) at 24 different locations during pre- (April–May 2003) and post- (September–October 2002) monsoon seasons. The δ15N of particulate organic nitrogen (PON) in surface suspended matter of coastal as well as northern open BOB shows signatures of a two end-member mixing between continental inputs and marine sources. Dilution by the organic and detrital continental material brought in by rivers leads to consistently lower δ15N, evident from the relationship between surface salinity and δ15N. δ15N of surface PON of open ocean locations during both seasons, and also at coastal locations during pre-monsoon suggest the nitrate from deeper waters as a predominant source of nutrient for planktons. The depth profiles of δ15N of SPM during pre-monsoon season at nine different locations are also presented. These indicate an increase in δ15N by a maximum of 2.8‰ between euphotic depth and 300 m, which is lower than that observed in the eastern Indian Ocean, indicating the role of higher sinking rates of particles ballasted by aggregates of organic and mineral matter in BOB.

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Kumar, S., R. Ramesh, N. B. Bhosle, S. Sardesai et M. S. Sheshshayee. « Natural isotopic composition of nitrogen in suspended particulate matter in the Bay of Bengal ». Biogeosciences Discussions 1, n^o 1 (4 juin 2004) : 87–105. http://dx.doi.org/10.5194/bgd-1-87-2004.

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Abstract. We present the first measurement of nitrogen isotopic composition (δ15N) in suspended particulate matter (SPM) of the surface Bay of Bengal (BOB) at 24 different locations during pre- (April–May 2003) and post- (September–October 2002) monsoon seasons. The δ15N of particulate organic nitrogen (PON) in surface suspended matter of coastal as well as northern open BOB shows signatures of a two end-member mixing between continental inputs and marine sources. Dilution by the organic and detrital continental material brought in by rivers leads to consistently lower δ15N, evident from the relationship between surface salinity and δ15N. δ15N of surface PON of open ocean locations during both seasons, and also at coastal locations during pre-monsoon suggest the nitrate from deeper waters as a predominant source of nutrient for planktons. The depth profiles of δ15N of SPM during pre-monsoon season at nine different locations are also presented. These indicate an increase in δ15N by a maximum of 2.8‰ between euphotic depth and 300 m, which is lower than that observed in the eastern Indian Ocean, indicating the role of higher sinking rates of particles ballasted by aggregates of organic and mineral matter in BOB.

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NG, HEOK HEE, et JEREMY J. WRIGHT. « Amblyceps cerinum, a new catfish (Teleostei : Amblycipitidae) from northeastern India ». Zootaxa 2672, n^o 1 (10 novembre 2010) : 50. http://dx.doi.org/10.11646/zootaxa.2672.1.3.

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Amblyceps cerinum, a new South Asian amblycipitid catfish species, is described from the Brahmaputra River drainage in northern West Bengal, India. The new species can be distinguished from congeners in having a combination of upper jaw longer than lower, incomplete lateral line terminating beneath posterior insertion of dorsal fin, length of adipose-fin base 32.4–38.3% SL, caudal peduncle length 21.9–24.5% SL, caudal peduncle depth 9.2–11.2% SL, 41–44 postWeberian vertebrae, posterior end of adipose fin separated from dorsal procurrent caudal-fin rays by distinct notch, and truncate caudal fin. The taxonomic status of A. tenuispinis is also discussed and a neotype designated for this species.

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Höpner, F., F. A. M. Bender, A. M. L. Ekman, P. S. Praveen, C. Bosch, J. A. Ogren, A. Andersson, Ö. Gustafsson et V. Ramanathan. « Vertical profiles of optical and microphysical particle properties above the northern Indian Ocean during CARDEX 2012 ». Atmospheric Chemistry and Physics Discussions 15, n^o 3 (12 février 2015) : 3907–53. http://dx.doi.org/10.5194/acpd-15-3907-2015.

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Abstract. A detailed analysis of optical and microphysical properties of aerosol particles during the dry winter monsoon season above the northern Indian Ocean is presented. The Cloud Aerosol Radiative Forcing Experiment (CARDEX), conducted in February and March 2012 at the Maldives Climate Observatory on Hanimaadhoo island (MCOH) in the Republic of the Maldives, used autonomous unmanned aerial vehicles (AUAV) to perform vertical in-situ measurements of particle number concentration, particle number size distribution as well as particle absorption. These measurements were used together with surface-based Mini Micro Pulse Lidar (MiniMPL) observations and aerosol in-situ and off-line measurements to investigate the vertical distribution of aerosol particles. Air masses were mainly advected over the Indian subcontinent and the Arabian Peninsula. Mean surface aerosol number concentration was 1717±604 cm−3 and the highest values were found in air masses from the Bay of Bengal and Indo–Gangetic Plain (2247±370 cm−3). Investigations of the free tropospheric air showed that elevated aerosol layers with up to 3 times higher aerosol number concentrations than at the surface occurred mainly during periods with air masses originating from the Bay of Bengal and the Indo–Gangetic Plain. Compared to the Indian Ocean Experiment (INDOEX) conducted in winter 1999, elevated aerosol layers with increased aerosol number concentration were observed more frequently in 2012. However, lower particle absorption at the surface (σabs(520 nm)=8.5±4.2 Wm−1) was found during CARDEX compared to INDOEX 1999. By combining vertical in-situ measured particle absorption with scattering calculated with Mie-theory, layers with single-scattering albedo (SSA) values of specific source regions were derived and utilized to calculate vertical particle absorption profiles from MiniMPL profiles. SSA surface values for dry conditions were found to be 0.94±0.02 and 0.91±0.02 for air masses from the Arabian Sea (and Middle East countries) and India (and Bay of Bengal), respectively. Lidar-derived particle absorption profiles showed both a similar magnitude and structure as the in-situ profiles measured with the AUAV. However, primarily due to insufficient accuracy in the SSA estimates, the lidar-derived absorption profiles have large uncertainties and are generally weakly correlated to vertically in-situ measured particle absorption. Furthermore, the mass absorption efficiency (MAE) for the northern Indian Ocean during the dry monsoon season was calculated to determine equivalent black carbon (EBC) concentrations from particle absorption measurements. A mean MAE of 11.6 and 6.9 m2 g−1 for 520 and 880 nm, respectively, was found, likely representing internally mixed BC containing particles. Lower MAE values for 880 nm were found for air masses originating from dust regions such as the Arabian Peninsula and western Asia (5.6 m2 g−1) or from closer source regions as southern India (4.3m2 g−1).

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A., BORODOVSKIY. « ARCHAEOLOGICAL STUDY OF THE CHUI TRACT IN THE AREA OF THE NECROPOLIS OF CHULTUKOV LOG-1 ». Preservation and study of the cultural heritage of the Altai Territory 28 (2022) : 403–9. http://dx.doi.org/10.14258/2411-1503.2022.28.58.

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The article is devoted to the analysis of the reasons for the location of ancient necropolises along the Chui Tract in Northern Altai. The purpose of the publication is to characterize the territory of the Chultuk burial complex Log-1. This necropolis, located in the mountain valley of the lower Katun during the 20th and 21st centuries, repeatedly fell into the zone of road construction. However, in the previous rather long historical period, this necropolis was formed on a naturally isolated territory. The orography of the right bank of the lower Katun consisted of several sections of the river valley, separated from each other by rock clamps. Several necropolises were formed near these natural obstacles in the Early Iron Age. The distance between such burial complexes ranged from 25 to 30 km. Such a feature of the location of ancient necropolises could reflect certain ethno-territorial boundaries of the Paleometallic epoch.

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Zolnikov, I. D., A. A. Anoikin, R. N. Kurbanov, E. A. Filatov, L. V. Zotkina, A. V. Vybornov, A. V. Postnov, E. V. Parkhomchuk et M. O. Filatova. « The Kushevat Site and the Paleogeographic Context of the Initial Peopling of Northern Urals ». Archaeology, Ethnology & ; Anthropology of Eurasia 51, n^o 2 (13 juillet 2023) : 27–37. http://dx.doi.org/10.17746/1563-0110.2023.51.2.027-037.

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On the basis of new materials excavated in 2019–2021 from the Upper Paleolithic site of Kushevat, this study addresses the problem of initial human occupation of the Subpolar Urals. Geological and geomorphological fi ndings are presented along with new chronological and paleogeographical data. Archaeological and faunal materials are described, and result s of the traceological analysis of reindeer antlers with cut and chop marks are presented. The fi ndings suggest that Kushevat was a pioneer settlement of the northern Ob region. The obtained luminescence and radiocarbon ages suggest that the peopling of the Lower Ob region occurred prior to 30 ka BP. Climatic conditions during the fi rst half of the Upper Paleolithic (55–25 ka BP) were favorable for humans in the subpolar zone. Geological and geomorphological situation at the Upper Paleolithic sites of northwestern Urals (the Pechora and Kama basins) can be used as a paleogeographic analogue of the conditions in the Lower Ob region during the Pleistocene. The principal Upper Paleolithic sites in the region are associated with accumulations of megafaunal remains in the mouths of ancient gullies. Archaeological sites apparently consisted of two areas differing in location, economic specialization, and toolkit. Areas of the fi rst type include residential zones on leveled areas of the second river terraces adjacent to the ravines. Those of the second type are estuarine zones of modern valleys of streams and rivers, where huge accumulations of megafaunal remains are preserved at the bottoms of ancient ravines.

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Höpner, F., F. A. M. Bender, A. M. L. Ekman, P. S. Praveen, C. Bosch, J. A. Ogren, A. Andersson, Ö. Gustafsson et V. Ramanathan. « Vertical profiles of optical and microphysical particle properties above the northern Indian Ocean during CARDEX 2012 ». Atmospheric Chemistry and Physics 16, n^o 2 (29 janvier 2016) : 1045–64. http://dx.doi.org/10.5194/acp-16-1045-2016.

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Abstract. A detailed analysis of optical and microphysical properties of aerosol particles during the dry winter monsoon season above the northern Indian Ocean is presented. The Cloud Aerosol Radiative Forcing Experiment (CARDEX), conducted from 16 February to 30 March 2012 at the Maldives Climate Observatory on Hanimaadhoo island (MCOH) in the Republic of the Maldives, used autonomous unmanned aerial vehicles (AUAV) to perform vertical in situ measurements of particle number concentration, particle number size distribution as well as particle absorption coefficients. These measurements were used together with surface- based Mini Micro Pulse Lidar (MiniMPL) observations and aerosol in situ and off-line measurements to investigate the vertical distribution of aerosol particles.Air masses were mainly advected over the Indian subcontinent and the Arabian Peninsula. The mean surface aerosol number concentration was 1717 ± 604 cm−3 and the highest values were found in air masses from the Bay of Bengal and Indo-Gangetic Plain (2247 ± 370 cm−3). Investigations of the free tropospheric air showed that elevated aerosol layers with up to 3 times higher aerosol number concentrations than at the surface occurred mainly during periods with air masses originating from the Bay of Bengal and the Indo-Gangetic Plain. This feature is different compared to what was observed during the Indian Ocean Experiment (INDOEX) conducted in winter 1999, where aerosol number concentrations generally decreased with height. In contrast, lower particle absorption at the surface (σabs(520 nm) = 8.5 ± 4.2 Wm−1) was found during CARDEX compared to INDOEX 1999.Layers with source region specific single-scattering albedo (SSA) values were derived by combining vertical in situ particle absorption coefficients and scattering coefficients calculated with Mie theory. These SSA layers were utilized to calculate vertical particle absorption profiles from MiniMPL profiles. SSA surface values for 550 nm for dry conditions were found to be 0.94 ± 0.02 and 0.91 ± 0.02 for air masses from the Arabian Sea (and Middle East countries) and India (and Bay of Bengal), respectively. Lidar-derived particle absorption coefficient profiles showed both a similar magnitude and structure as the in situ profiles measured with the AUAV. However, primarily due to insufficient accuracy in the SSA estimates, the lidar-derived absorption coefficient profiles have large uncertainties and are generally weakly correlated to vertically in situ measured particle absorption coefficients.Furthermore, the mass absorption efficiency (MAE) for the northern Indian Ocean during the dry monsoon season was calculated to determine equivalent black carbon (EBC) concentrations from particle absorption coefficient measurements. A mean MAE of 11.6 and 6.9 m2 g−1 for 520 and 880 nm, respectively, was found, likely representing internally mixed BC containing particles. Lower MAE values for 880 and 520 nm were found for air masses originating from dust regions such as the Arabian Peninsula and western Asia (MAE(880 nm) = 5.6 m2 g−1, MAE(520 nm) = 9.5 m2 g−1) or from closer source regions as southern India (MAE(880 nm) = 4.3 m2 g−1, MAE(520 nm) = 7.3 m2 g−1).

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Caulle, C., K. A. Koho, M. Mojtahid, G. J. Reichart et F. J. Jorissen. « Live (Rose Bengal stained) foraminiferal faunas from the northern Arabian Sea : faunal succession within and below the OMZ ». Biogeosciences 11, n^o 4 (26 février 2014) : 1155–75. http://dx.doi.org/10.5194/bg-11-1155-2014.

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Abstract. Live (Rose Bengal stained) benthic foraminifera from the Murray Ridge, within and below the northern Arabian Sea oxygen minimum zone (OMZ), were studied in order to determine the relationship between faunal composition, bottom water oxygenation (BWO), pore water chemistry and organic matter (organic carbon and phytopigment) distribution. A series of multicores were recovered from a ten-station oxygen (BWO: 2–78 μM) and bathymetric (885–3010 m depth) transect during the winter monsoon in January 2009. Foraminifera were investigated from three different size fractions (63–125 μm, 125–150 μm and >150 μm). The larger foraminifera (>125 μm) were strongly dominated by agglutinated species (e.g. Reophax spp.). In contrast, in the 63–125 μm fraction, calcareous taxa were more abundant, especially in the core of the OMZ. On the basis of a principal components analysis, three foraminiferal groups were identified and correlated to the environmental parameters by canonical correspondence analysis. The faunas from the shallowest stations, in the core of the OMZ (BWO: 2 μM), were composed of "low oxygen" species, typical of the Arabian Sea OMZ (e.g. Rotaliatinopsis semiinvoluta, Praeglobobulimina sp., Bulimina exilis, Uvigerina peregrina type parva). These taxa are adapted to the very low BWO conditions and to high phytodetritus supplies. The transitional group, typical for the lower part of the OMZ (BWO: 5–16 μM), is composed of species that are tolerant as well to low-oxygen concentrations, but may be less critical with respect to organic supplies (e.g. Globocassidulina subglobosa, Ehrenbergina trigona). Below the OMZ (BWO: 26–78 μM), where food availability is more limited and becomes increasingly restricted to surficial sediments, cosmopolitan calcareous taxa were present, such as Bulimina aculeata, Melonis barleeanus, Uvigerina peregrina and Epistominella exigua. Miliolids were uniquely observed in this last zone, reflecting the higher BWO and/or lower organic input. At these deeper sites, the faunas exhibit a clear succession of superficial, intermediate and deep infaunal microhabitats, which can be linked to the deeper oxygen and nitrate penetration into the sediment.

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25

Vasilyeva, I. N., N. S. Doga et F. F. Gilyazov. « NEW DATA ON THE NEOLITHIC POTTERY OF THE LOWER VOLGA REGION ». Izvestiya of Samara Scientific Center of the Russian Academy of Sciences. History Sciences 5, n^o 1 (2023) : 137–50. http://dx.doi.org/10.37313/2658-4816-2023-5-1-137-150.

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The article presents data on newly discovered ceramic complexes obtained during archaeological research of the Neolithic sites of the Lower Volga region (Taskuduk, Priozernaya, Algay) in 2021-2022. The results of statistical, morphological and technical-technological analysis of ceramics made it possible to compare the ancient pottery production in different landscape zones of the Lower Volga region: the semi-desert Northern Caspian region and the steppe Lower Volga region. New radiocarbon data obtained at the Isotope Research Laboratoryof the Russian State Pedagogical University in the name of A.I. Herzen (St. Petersburg), and drawing analogies with other well-known sites in the region (Tenteksor, Zhe-Kalgan I, Varfolomeevskaya site) allow us to consider the newly discovered complexes as simultaneous and attribute them to the Late Neolithic.Morphological analysis of pottery complexes belonging to different cultures made it possible to reveal both common features (shape of vessels, flatness, decoration of vessels with pricking and indentation, presence of thickening on the inside of the rims) and differences (shape of pricks, ornamental compositions and motifs). The Neolithic materials of the Lower Volga region can be united within the framework of the Lower Volga cultural-historical community (LVCC) with division into regional cultures: Orlovskaya, Dzhangar, Kairshak-Tenteksor (Seroglazovskaya), which have signs of a common origin, common patterns of development and cultural interaction during all the Neolithic. The researchers revealed the existence of an early Neolithic center of the origin of pottery in the Lower Volga region, traced its evolutionary development and regional characteristics, reconstruct the archaic (pre-pottery) ideas of the ancient population about silts as a raw material for the production of dishes. In contrast to the Northern Caspian, where archaic traditions of silt selection were preserved even at the late stage of the Neolithic, in the steppe Volga region the new types of raw materials, such as silty clays and clays, appeared simultaneously with the traditional types and then became widespread. Identification of the causes of this phenomenon (climate changes or the emergence of new groups of the Neolithic population) requires further research.

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Sarker, Archishman. « Reflections on the material and making of an image in ancient/early-medieval northern Bengal (Varendrī region) during the Pāla-Sena period (6th-13th C.E.) ». International Journal of English Literature and Social Sciences 4, n^o 1 (2019) : 147–51. http://dx.doi.org/10.22161/ijels.4.1.30.

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Heimlich, Geoffroy, Pascale Richardin, Nathalie Gandolfo, Eric Laval et Michel Menu. « First Direct Radiocarbon Dating of the Lower Congo Rock Art (Democratic Republic of the Congo) ». Radiocarbon 55, n^o 3 (2013) : 1383–90. http://dx.doi.org/10.1017/s0033822200048311.

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Lower Congo rock art is concentrated in a region that stretches from Kinshasa to the Atlantic coast and from northern Angola to southern Congo-Brazzaville. Although Lower Congo rock art was identified as early as the 19th century, it had never been a subject of thorough investigation. Presently inhabited by the Ndibu, one of the Kongo subgroups, the Lovo Massif is situated north of the ancient Kongo Kingdom. With 102 sites (including 16 decorated caves), the massif has the largest concentration of rock art in the entire region. In 2008 and 2010, we were able to collect pigment samples directly on the panels of the newly discovered decorated cave of Tovo. Unlike the Sahara and southern Africa, both extensively prospected, rock art of central Africa is still widely unknown and not dated. Radiocarbon dating of rock art in Africa is a real challenge and only a few direct dates have been obtained thus far. After verifying that the pigment samples were indeed charcoal, we proceeded to 14C date them using accelerator mass spectrometry (AMS). The results indicate dates between cal AD 1480 and 1800, confirming that the occupation of Tovo Cave was contemporaneous with the ancient Kongo Kingdom.

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Chowdhury, Kamrun Nahar, Md Kawser Ahmed, Kazi Turjaun Akhter, Seema Rani et Makidul Islam Khan. « Minerals and Heavy Metal Composition in Seaweeds of the Eastern Coast, Northern Bay of Bengal, Bangladesh ». Dhaka University Journal of Earth and Environmental Sciences 10, n^o 2 (19 janvier 2022) : 43–52. http://dx.doi.org/10.3329/dujees.v10i2.57514.

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This study aimed to analyze minerals (Ca, Mg, Fe, Zn, Mn and Cu) and heavy metals (Pb and Cd) content of seaweeds collected from coastal waters of Bangladesh using Atomic Absorption Spectrophotometer (AAS). Eight wild species in three phyla viz. Rhodophyta (Hypnea sp.), Chlorophyta (Enteromorphasp.),and Phaeophyta (Sargassumsp.,Hydroclathrusclathratus, Padinapavonica, Colpomeniasinuosa, Petalonia fascia and Dictyotaciliolata)and one cultured Rhodophyta species viz. Hypnea sp. were collected from St. Martin’s Island and Cox’s Bazar, respectively. Results showed minerals and heavy metals concentrations were varied from species to species. Ca concentration was the highest in Phaeophyta (18565 mg/kg-dw) and it was 19 times higher than the value reported in Chlorophyta (950 mg/kg-dw). In contrast, Fe, Zn and Mn were the highest in Rhodophyta. This is because different groups of seaweeds affinity to absorb minerals depend on environmental parameters for example salinity, pH and light intensity, mineral accessibility in sea water and interactions between elements, growth and metabolic factors, etc. Ca content was the highest in C. sinuosa (30890 mg/kg-dw), whereas, it was the lowest in cultured Hypnea sp. (120 mg/kg-dw). P.pavonica showed the highest concentrations of Fe (15030 mg/kg-dw), Zn (33.46 mg/kg-dw) and Mn (443.79 mg/kg-dw). Mineral contents of cultured seaweeds were comparatively lower than the wild species. Results showed mineral concentrations in all seaweeds were relatively greater than heavy metals. However, wild Hypneasp. contained slightly 2 times higher Cd (2.11 mg/kg-dw) than the cultured Hypnea sp. (0.98 mg/kg-dw) due to higher level of anthropogenic source of pollution in St. Martin’s Island. Heavy metal contamination in seaweeds might raise health concerns among the consumers. Findings of this study might help to unleash minerals and heavy metals compositions of the studied seaweeds of Bangladesh. Policy makers can formulate and establish health safety guidelines for safe consumption of seaweeds. The Dhaka University Journal of Earth and Environmental Sciences, Vol. 10(2), 2021, P 43-52

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Caulle, C., K. A. Koho, M. Mojtahid, G. J. Reichart et F. J. Jorissen. « Live foraminiferal faunas (Rose Bengal stained) from the northern Arabian Sea : links with bottom-water oxygenation ». Biogeosciences Discussions 10, n^o 9 (23 septembre 2013) : 15257–304. http://dx.doi.org/10.5194/bgd-10-15257-2013.

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Abstract. Live (Rose Bengal stained) benthic foraminifera from the Murray Ridge, within and below the northern Arabian Sea Oxygen Minimum Zone (OMZ), were studied in order to determine the relationship between faunal composition, bottom-water oxygenation (BWO), pore-water chemistry and organic matter (organic carbon and phytopigment) distribution. A series of multicores were recovered from a ten-station oxygen (BWO: 2–78 μM) and bathymetric (885–3010 m depth) transect during the winter monsoon in January 2009. Foraminifera were investigated from three different size fractions (63–125 μm, 125–150 μm and > 150 μm). The larger foraminifera (> 125 μm) were strongly dominated by agglutinated species (e.g. Reophax spp.). In contrast, in the 63–125 μm fraction, calcareous taxa were more abundant, especially in the core of the OMZ, suggesting an opportunistic behaviour. On the basis of a Principal Component Analysis, three foraminiferal groups were identified, reflecting the environmental parameters along the study transect. The faunas from the shallowest stations, in the core of the OMZ (BWO: 2 μM), were composed of "low oxygen" species, typical of the Arabian Sea OMZ (e.g., Rotaliatinopsis semiinvoluta, Praeglobobulimina spp. , Bulimina exilis, Uvigerina peregrina typeparva). These taxa are adapted to the very low BWO conditions and to high phytodetritus supplies. The transitional group, typical for the lower part of the OMZ (BWO: 5–16 μM), is composed of more cosmopolitan taxa tolerant to low-oxygen concentrations (Globocassidulina subglobosa, Ehrenbergina trigona). Below the OMZ (BWO: 26–78 μM), where food availability is more limited and becomes increasingly restricted to surficial sediments, more cosmopolitan calcareous taxa were present, such as Bulimina aculeata, Melonis barleeanus, Uvigerina peregrina and Epistominella exigua. Miliolids were uniquely observed in this last group, reflecting the higher BWO. At these deeper sites, the faunas exhibit a clear depth succession of superficial, intermediate and deep-infaunal microhabitats, because of the deeper oxygen and nitrate penetration into the sediment.

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Akhand, Anirban, Abhra Chanda, Kenta Watanabe, Sourav Das, Tatsuki Tokoro, Kunal Chakraborty, Sugata Hazra et Tomohiro Kuwae. « Low CO2 evasion rate from the mangrove-surrounding waters of the Sundarbans ». Biogeochemistry 153, n^o 1 (mars 2021) : 95–114. http://dx.doi.org/10.1007/s10533-021-00769-9.

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AbstractGlobally, water bodies adjacent to mangroves are considered significant sources of atmospheric CO2. We directly measured the partial pressure of CO2 in water [pCO2(water)] and related biogeochemical parameters with high temporal resolution, covering both diel and tidal cycles, in the mangrove-surrounding waters around the northern Bay of Bengal during the post-monsoon season. Mean pCO2(water) was marginally oversaturated in two creeks (470 ± 162 µatm, mean ± SD) and undersaturated in the adjoining estuarine stations (387 ± 58 µatm) compared to atmospheric pCO2, and was considerably lower than the global average. We further estimated the pCO2(water) and buffering capacity of all possible sources of the mangrove-surrounding waters and concluded that their character as a CO2 sink or weak source is due to the predominance of marine water from the Bay of Bengal with low pCO2 and high buffering capacity. Marine water with high buffering capacity suppresses the effect of pCO2 increase within the mangrove system and lowers the CO2 evasion even in creek stations. The δ13C of dissolved inorganic carbon (DIC) in the mangrove-surrounding waters indicated that the DIC sources were a mixture of mangrove plants, pore-water, and groundwater, in addition to marine water. Finally, we showed that the CO2 evasion rate from the estuaries of the Sundarbans is much lower than the recently estimated world average. Our results demonstrate that mangrove areas having such low emissions should be considered when up-scaling the global mangrove carbon budget from regional observations.

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Silva, P. G., J. L. Giner-Robles, J. Elez, E. Roquero, M. A. Rodríguez-Pascua, R. Pérez-López, A. Martínez-Graña, T. Bardají et M. A. Perucha. « Historical earthquakes in the Lower Segura basin (SE Spain) : geological and archaeological evidence from pre-roman to modern times ». Zeitschrift für Geomorphologie, Supplementary Issues 62, n^o 2 (1 octobre 2019) : 247–69. http://dx.doi.org/10.1127/zfg_suppl/2018/0492.

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This paper deals with the analysis of ancient and historical earthquakes in the Lower Segura Depression (SE Spain) at the northern end of the Eastern Betic Cordillera Shear Zone (EBSZ), which is defined within the area by the Lower Segura blind-thrust fault. The work summarizes and updates the existing information on the building and environmental damage dispersed throughout several historical documents, as well as the new historical and archaeological research on the area. The analyses performed consider the evolving paleogeography of the old estuarine zone defined by Ibero-Roman "Sinus ilicitanus" and the ancient prograding delta of the Segura River over the marshes. Topographic data from old descriptions of the zone together with the analysis of the geometry of the medieval irrigation system in the growing delta from pre-Roman to modern (18th century) times, allow the paleogeographic evolution of the zone, until the eventual artificial infilling of the old embayment, to be outlined. Several strong earth- quakes (Intensity ≥ VIII EMS-98) occurred in the area during different historical times. Building damage for the different events was variable depending on the number of settlements (and increasing population) within the ancient embayment. Maximum Intensity X during the most recent earthquake (AD 1829 Torrevieja) mainly occurred over old lands reclaimed in the 18 th century. In addition, dominant earthquake secondary effects (EEEs) were caused by liquefaction processes. This study analyzes the dimensions and distribution of these EEEs for the two main earthquakes in the zone during the years AD 1048 and AD 1829 using the ESI-07 intensity scale. The results draw important inferences on the role of ancient paleo-geography in seismic hazard data from past earthquakes.

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Clapp, Corey E., Jessica B. Smith, Kristopher M. Bedka et James G. Anderson. « Distribution of cross-tropopause convection within the Asian monsoon region from May through October 2017 ». Atmospheric Chemistry and Physics 23, n^o 5 (14 mars 2023) : 3279–98. http://dx.doi.org/10.5194/acp-23-3279-2023.

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Abstract. We constructed a database of cross-tropopause convection in the Asian monsoon region for the months of May through October of 2017 using overshooting tops (OTs), deep convective features that penetrate the local cirrus anvil layer and the local tropopause, with Meteosat-8 geostationary satellite detections. The database of 40 918 OTs represents a hemispheric record of convection covering the study domain from 10∘ S to 55∘ N and from 40 to 115∘ E. With this database, we analyzed the geographic, monthly, and altitude distribution of this convection and compared it to the convective distributions represented by satellite observations of outgoing longwave radiation (OLR) and precipitation. We find that cross-tropopause convection is most active during the months of May through August (with daily averages of these months above 300 OTs per day) and declines through September and October. Most of this convection occurs within Northern India and Southern India, the Bay of Bengal, and the Indian Ocean regions, which together account for 75.1 % of all OTs. We further identify distinct, differing seasonal trends within the study subregions. For the Northern India, Southern India, and Bay of Bengal regions, the distribution of OTs follows the development of the Asian monsoon, with its north–south movement across the study period. This work demonstrates that when evaluating the effects of convection on lower stratospheric composition over the Asian monsoon region, it is important to consider the impact of cross-tropopause convection specifically, as well as the contributions from both land-based and oceanic regions due to the significant geographic and monthly variation in convective activity.

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33

Banerji, Chitrita. « The Propitiatory Meal ». Gastronomica 3, n^o 1 (2003) : 82–89. http://dx.doi.org/10.1525/gfc.2003.3.1.82.

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This article is an analysis of the varied ways in which the meal has been used as a tool for appeasement and propitiation in Bengali Hindu society from ancient times. Bengal is a region that is naturally fertile and yet is often subjected to the fearsome destruction of floods and cyclones. The uncertainty of life has always been palpable here. The numerous rivers that make the region a delta also made Bengal the last hinterland of Aryan exploration and settlement in ancient times. Pre-Aryan inhabitants, whom historians describe as proto-Australoid, subscribed to animistic beliefs, which blurred the line between this world and the next. Their funerary practices involved serving food to supernatural creatures who inhabited the earth. In such a region, the imposition of the Hindu caste system, which attributed preeminence to the Brahmins and the males, further increased the sense of vulnerability on the part of a large section of the population'women and members of the lower castes. Mythic notions of food as something with which to appease a dangerous creature eventually translated into the social custom of serving carefully prepared meals to gods, Brahmins, males and other beings with power and superiority. The article presents examples from mythology, religious texts, literature and even film, to illustrate this custom. Widows were particularly vulnerable in Bengali Hindu society. They were not allowed to remarry and also blamed for the death of their husbands. The rituals and deprivations of a widow's life provide the most poignant instances of appeasement through food. One of the best-known rituals of propitiation is the Bengali feast of Jamaishashthi, when the son-in-law is invited by his wife's family and served an elaborate multi-course meal. He is also given expensive gifts. The purpose of the ritual was to ensure that he treats his wife well and protects her from being treated too abusively by his mother and sisters. The practice has survived in modern times even though it has lost much of its potent significance.

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Woziwoda, Beata, Marcin K. Dyderski, Agnieszka Parzych, Jerzy Jonczak et Andrzej M. Jagodziński. « Loss in macronutrient pools in bilberry and lingonberry in mesic Scots pine forests after Northern red oak introduction ». European Journal of Forest Research 140, n^o 6 (28 septembre 2021) : 1499–514. http://dx.doi.org/10.1007/s10342-021-01414-8.

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AbstractForest transformation from coniferous monocultures to mixed stands is being promoted worldwide, including the introduction of fast-growing broadleaved tree species within native stands. Here, we studied how enrichment of temperate European Scots pine (Pinus sylvestris) forest by North-American northern red oak Quercus rubra impacted macronutrient concentrations in two long-lived and dominant components of the forest understory: bilberry Vaccinium myrtillus and lingonberry V. vitis-idaea. Study sites were located in forest complexes (central Poland) which occupy continuously reforested lands (hereafter ancient forests) as well as post-agricultural lands (recent forests), all suitable for mesic pine forests. Samples of bilberry and lingonberry leaves, stems, and fruits were collected in pine stands and in adjacent Scots pine-red oak stands, in both ancient and recent forests. Concentrations of macronutrients (C, N, P, K, Ca, S, and Mg) in aboveground biomass components were analysed using standardized chemical procedures. The study revealed intra- and interspecific (bilberry vs. lingonberry) differences in concentrations of all nutrients in leaves, stems, and fruits, except for invariable C concentrations. Macronutrient accumulations in plants were decreased by land-use discontinuity and favoured by enrichment of tree stands by Q. rubra. The estimated macronutrient pools were much higher for V. myrtillus than V. vitis-idaea in all forest types studied. They were lower in forests enriched with Q. rubra, both ancient (up to 25.5% for bilberry and 99.9% for lingonberry) and recent (46.9% and 99.9%, respectively), as well as in recent pine forest (46.6% and 81.1%, respectively) than in ancient pine forest. Higher K and S pools (39.3% and 6.5%, respectively) noted for bilberry in an ancient forest with Q. rubra were exceptions. Despite more effective accumulations of elements at the species level, macronutrient pools of Vaccinium myrtillus and V. vitis-idaea decreased significantly in the presence of introduced Q. rubra due to negative impacts of this broadleaved tree on bilberry and lingonberry cover and biomass. Therefore, the limitation of alien Q. rubra planting in sites of mesic pine forest with the abundant occurrence of V. myrtillus and/or V. vitis-idaea is recommended. Graphic abstract

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KLOTZ, WERNER. « Macrobrachium agwi - a new species of freshwater prawn (Decapoda : Palaemonidae) from East Bengal, India ». Zootaxa 1844, n^o 1 (6 août 2008) : 47. http://dx.doi.org/10.11646/zootaxa.1844.1.4.

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Freshwater prawns do not only have economic importance in hydroponics and fisheries for food purposes, but also recently receive increasing attention in aquarium trade (Karge & Klotz 2007). An examination of some prawns imported as ‘ornamental shrimps’ from Cooch Behar, East Bengal, India to Europe revealed that they belong to a hitherto undescribed species of the genus Macrobrachium and are described here in detail. The new species belong to the group of specimen with large eggs, indicating abbreviated or direct larval development in freshwater, occurring in inland river systems (Tiwari 1955b). Morphological M. agwi nov.sp. is most similar to M. kempi (Tiwari, 1947) first described from Chittagong, Bangladesh, M. altifrons altifrons (Henderson, 1893) from Northern India and Nepal and M. hendersoni (De Man, 1906) known from hill streams in East India and Myanmar. Though the proposed new species can be distinguished from M. kempi by lacking a dense fur of setae on the lower margin of the propodus of male large cheliped, from M. altifrons by the shape and armature of second chelae and from M. hendersoni by lacking longitudinal groves covered with fine hairs on fingers of second chelipeds.

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Cai, Yu, Hiromi Yamazawa et Takeshi Iimoto. « 210Pb Deposition Distribution in the Northern Hemisphere Based on a Long-Range Atmospheric Transport and Deposition Model Calculation ». Atmosphere 14, n^o 9 (23 août 2023) : 1329. http://dx.doi.org/10.3390/atmos14091329.

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This study delves into the long-term atmospheric transport and deposition of 210Pb in the Northern Hemisphere by using the atmospheric transport model HIRAT. The calculation for the four-year (2012–2015) period showed an average deposition flux of 13.0 Bq m−2 month−1 with significant seasonal variations characterized by higher deposition rates during summer and lower during winter. High deposition was found in the Northern Bay of Bengal and Bangladesh regions, Southern China, the Western Philippine Sea, the Eastern Japan Sea, the Northwestern Pacific region, the Eastern and Western coasts of North America, the Caribbean Sea, the Eastern Pacific region off of Central America, the Central Atlantic region between Central America and Africa, and the Northwestern Atlantic Ocean. Deposition patterns varied across latitudinal zones, with tropical areas experiencing the highest deposition and polar/subpolar zones the lowest. This study emphasized the impact of monsoons on the significantly large 210Pb deposition in the Japan Sea region. Furthermore, this study showed that the lower troposphere (0 to 3 km) dominates with about 53%, and the middle troposphere (3 to 6 km) and upper troposphere (above 6 km) also contribute significantly to the total 210Pb inventory with 37% and 10%, respectively. These findings provide essential insights into the characteristics of atmospheric transport and deposition of 210Pb, and their mechanisms.

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Enshin, D. N. « Neolithic pottery from the settlement of Mergen 6 in the Lower Ishim (groups III and IV) : characteristics and interpretation ». VESTNIK ARHEOLOGII, ANTROPOLOGII I ETNOGRAFII, n^o 2(57) (15 juin 2022) : 17–30. http://dx.doi.org/10.20874/2071-0437-2022-57-2-2.

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In this paper, a ceramic complex (groups III and IV) of the early Neolithic settlement of Mergen 6 (Lower Ishim River region, Western Siberia, 7th millennium BC) is examined. The aim of the work is to analyze the mate-rials through the prism of contacts, connections and mixing of different cultural traditions in the early Neolithic period of the Trans-Urals and Western Siberia. The research is based on the elements of the historical-cultural and formal-classification approaches. The source base comprises 284 vessels. As the result of the analysis car-ried out in several stages (morphology of the vessels, tools and techniques for applying ornamentation, structural components of the decor, the nature of the systematic organization of the ornamental components, and relation-ship between the image components and structure of the vessel’s shape), it was found that the products of group III correspond to the tradition of making vessels with relief bands of the taiga zone of Western Siberia and the Urals (Sa-tyginsky, Mulymyinsky types, etc.), whereas those of group IV demonstrate a mixture of all pottery traditions iden-tified within the complex. On this basis, the main directions of the sociocultural ties of the ancient population of the Lower Ishim region in the early Neolithic period have been determined — western (the Middle and Southern Trans-Urals), north-western (the taiga zone of Western Siberia and the southern Northern Trans-Urals), and, probably, southern (the steppes of modern Northern Kazakhstan). One of the most important factors of the vari-ability of the early Neolithic pottery has been identified — the interaction and mixing of different communities. All this allows speaking about the settlement of Mergen 6 as a center (cultural, economic, sacred (?)) at the intersec-tion of landscape and geographical zones (steppe — forest, Trans-Urals — Western Siberia) and ways of disper-sal of various groups of the ancient population.

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d'Lemos, R. S., et M. Brown. « Sm–Nd isotope characteristics of late Cadomian granite magmatism in northern France and the Channel Islands ». Geological Magazine 130, n^o 6 (novembre 1993) : 797–804. http://dx.doi.org/10.1017/s0016756800023165.

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AbstractSm–Nd isotopic studies of granites within the late Precambrian, Cadomian, orogenic belt of the North Armorican Massif (northwestern France) and Channel Islands reveal differences between arc-related granite magmatism in outboard terranes and intracrustal granite magmatism in inboard terranes. Late Cadomian (c. 570 Ma), arc-related granitoids exhibit a range of εnd( - 2 to - 6) and Nd model ages (TDM1.0–1.3 Ga) reflecting variable contamination between late Precambrian mantle derived magmas and ancient (c. 2.0 Ga?) continental crust. The contamination did not involve exposed granitic Icartian basement to anygreat degree, a more likely contaminant being unexposed lower crust of intermediate to acidic granulitic composition, or early Cadomian plutons which were themselves contaminated by lower crust. Voluminous granites of the Mancellian region (c. 550–540 Ma) share common isotopic characteristics (εNd-4 to -7, TDM1.5–1.7 Ga) with migmatites and anatectic granites produced by partial melting of metasedimentary sequences within the St Malo region consistent with a common source.

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Rixen, Tim, Greg Cowie, Birgit Gaye, Joaquim Goes, Helga do Rosário Gomes, Raleigh R. Hood, Zouhair Lachkar, Henrike Schmidt, Joachim Segschneider et Arvind Singh. « Reviews and syntheses : Present, past, and future of the oxygen minimum zone in the northern Indian Ocean ». Biogeosciences 17, n^o 23 (4 décembre 2020) : 6051–80. http://dx.doi.org/10.5194/bg-17-6051-2020.

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Abstract. Decreasing concentrations of dissolved oxygen in the ocean are considered one of the main threats to marine ecosystems as they jeopardize the growth of higher organisms. They also alter the marine nitrogen cycle, which is strongly bound to the carbon cycle and climate. While higher organisms in general start to suffer from oxygen concentrations < ∼ 63 µM (hypoxia), the marine nitrogen cycle responds to oxygen concentration below a threshold of about 20 µM (microbial hypoxia), whereas anoxic processes dominate the nitrogen cycle at oxygen concentrations of < ∼ 0.05 µM (functional anoxia). The Arabian Sea and the Bay of Bengal are home to approximately 21 % of the total volume of ocean waters revealing microbial hypoxia. While in the Arabian Sea this oxygen minimum zone (OMZ) is also functionally anoxic, the Bay of Bengal OMZ seems to be on the verge of becoming so. Even though there are a few isolated reports on the occurrence of anoxia prior to 1960, anoxic events have so far not been reported from the open northern Indian Ocean (i.e., other than on shelves) during the last 60 years. Maintenance of functional anoxia in the Arabian Sea OMZ with oxygen concentrations ranging between > 0 and ∼ 0.05 µM is highly extraordinary considering that the monsoon reverses the surface ocean circulation twice a year and turns vast areas of the Arabian Sea from an oligotrophic oceanic desert into one of the most productive regions of the oceans within a few weeks. Thus, the comparably low variability of oxygen concentration in the OMZ implies stable balances between the physical oxygen supply and the biological oxygen consumption, which includes negative feedback mechanisms such as reducing oxygen consumption at decreasing oxygen concentrations (e.g., reduced respiration). Lower biological oxygen consumption is also assumed to be responsible for a less intense OMZ in the Bay of Bengal. According to numerical model results, a decreasing physical oxygen supply via the inflow of water masses from the south intensified the Arabian Sea OMZ during the last 6000 years, whereas a reduced oxygen supply via the inflow of Persian Gulf Water from the north intensifies the OMZ today in response to global warming. The first is supported by data derived from the sedimentary records, and the latter concurs with observations of decreasing oxygen concentrations and a spreading of functional anoxia during the last decades in the Arabian Sea. In the Arabian Sea decreasing oxygen concentrations seem to have initiated a regime shift within the pelagic ecosystem structure, and this trend is also seen in benthic ecosystems. Consequences for biogeochemical cycles are as yet unknown, which, in addition to the poor representation of mesoscale features in global Earth system models, reduces the reliability of estimates of the future OMZ development in the northern Indian Ocean.

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Roden, Vanessa Julie, Martin Zuschin, Alexander Nützel, Imelda M. Hausmann et Wolfgang Kiessling. « Drivers of beta diversity in modern and ancient reef-associated soft-bottom environments ». PeerJ 8 (14 mai 2020) : e9139. http://dx.doi.org/10.7717/peerj.9139.

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Beta diversity, the compositional variation among communities, is often associated with environmental gradients. Other drivers of beta diversity include stochastic processes, priority effects, predation, or competitive exclusion. Temporal turnover may also explain differences in faunal composition between fossil assemblages. To assess the drivers of beta diversity in reef-associated soft-bottom environments, we investigate community patterns in a Middle to Late Triassic reef basin assemblage from the Cassian Formation in the Dolomites, Northern Italy, and compare results with a Recent reef basin assemblage from the Northern Bay of Safaga, Red Sea, Egypt. We evaluate beta diversity with regard to age, water depth, and spatial distance, and compare the results with a null model to evaluate the stochasticity of these differences. Using pairwise proportional dissimilarity, we find very high beta diversity for the Cassian Formation (0.91 ± 0.02) and slightly lower beta diversity for the Bay of Safaga (0.89 ± 0.04). Null models show that stochasticity only plays a minor role in determining faunal differences. Spatial distance is also irrelevant. Contrary to expectations, there is no tendency of beta diversity to decrease with water depth. Although water depth has frequently been found to be a key factor in determining beta diversity, we find that it is not the major driver in these reef-associated soft-bottom environments. We postulate that priority effects and the biotic structuring of the sediment may be key determinants of beta diversity.

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Seitz, Carina, María I. Vélez et Gerardo M. E. Perillo. « Cenozoic geologic evolution of the lower Colorado River Basin, Northern Patagonia, Argentina ». Andean Geology 46, n^o 1 (28 septembre 2018) : 131. http://dx.doi.org/10.5027/andgeov46n1-3060.

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Climatic changes and eustatic sea levels have been assumed to be the most important controllers of the Colorado River alluvial fan in northern Patagonia. Although the alluvial fan occurs in a region considered tectonically stable, there are pieces of evidence that the Miocene Andean orogeny has reactivated inherited structures, with subsequent geomorphological changes that date back to the Pleistocene. Besides, the clear evidence of neotectonism in the region and their effects on the evolution of this fan, it has not been studied in detail yet. In this study, we map and analyze six sections outcropping in different terraces of the alluvial fan with the primary aim of disentangling the role of tectonism, climate and eustatic changes on the evolution of the alluvial fan. This study is part of a bigger project aimed to understand the origin of the shallow lakes occurring in northern Patagonia. Our results indicate that the alluvial fan of the Colorado River was established in the area around the Middle Pleistocene. Evidence of deformations in Miocene to Pleistocene units indicates significant neotectonism during the Upper Pleistocene. By the Pleistocene-Holocene transition, tectonism produced incision generating a set of terraces. After this time, an important climate change from semiarid to arid favored the calcretization of some terraces. By the Pleistocene-Middle Holocene, the terraces were covered by ancient eolian sediment accumulated during dry conditions. By the Middle Holocene, a broad alluvial fan developed in the region under a warmer and more humid climate generating the Alluvial Colorado River-III deposit at the T3 terrace. In the late Holocene, aggradation process was favored by a high sea level and temperate-arid climate, producing T4 terrace. At the same time, this climate condition favored the local deflation-sedimentation processes that resulted in the deposition of modern eolian deposits (mE) over the T3 terrace. The depressions generated by the deflation were, later on, occupied by shallow lakes when the climate turn more humid. Subsequently, during regressive sea level condition, ca. 2000 years BP, the T4 terrace was partially eroded and the modern alluvial plain formed.

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Zhao, Yu, Anmin Duan, Guoxiong Wu et Ruizao Sun. « Response of the Indian Ocean to the Tibetan Plateau Thermal Forcing in Late Spring ». Journal of Climate 32, n^o 20 (16 septembre 2019) : 6917–38. http://dx.doi.org/10.1175/jcli-d-18-0880.1.

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Abstract The thermal effect of the Tibetan Plateau (TP) is known to exert substantial impacts on the atmospheric general circulation, suggesting that it may also influence the wind-driven circulation in the ocean through air–sea interactions. Here, several coupled general circulation model experiments are performed in order to investigate the short-term response of the Indian Ocean to the TP surface heat source in late spring (May). The results indicate that positive TP heating anomalies can induce significant atmospheric circulation responses over the northern Indian Ocean, characterized by easterly anomalies in the upper troposphere due to the enhanced South Asian high and lower-level southwesterly anomalies from the heat pumping effect. As a result, the surface wind speed over the northern Indian Ocean is reinforced, leading to intensified oceanic evaporation and subsequently cooler potential temperatures in the mixed layer. Wind-driven currents in the mixed layer are also affected. In the Bay of Bengal, Ekman transport facilitates water volume movement from west to east. In the Arabian Sea, water movement is weaker and the southward component is relatively more important. Both these areas show local meridional circulations with offshore upwelling in the northwest. Moreover, the cross-equatorial current is also enhanced in the eastern part of the tropical Indian Ocean. Overall, the upper layer in the northern Indian Ocean is efficiently modulated by the TP thermal forcing within one month.

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Harrison-Buck, Eleanor, et Sara Clarke-Vivier. « Making Space for Heritage : Collaboration, Sustainability, and Education in a Creole Community Archaeology Museum in Northern Belize ». Heritage 3, n^o 2 (31 mai 2020) : 412–35. http://dx.doi.org/10.3390/heritage3020025.

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Working with local partners, we developed an archaeology museum in the Creole community of Crooked Tree in the Maya lowlands of northern Belize. This community museum presents the deep history of human–environment interaction in the lower Belize River Watershed, which includes a wealth of ancient Maya sites and, as the birthplace of Creole culture, a rich repository of historical archaeology and oral history. The Creole are descendants of Europeans and enslaved Africans brought to Belize—a former British colony—for logging in the colonial period. Belizean history in schools focuses heavily on the ancient Maya, which is well documented archaeologically, but Creole history and culture remain largely undocumented and make up only a small component of the social studies curriculum. The development of a community archaeology museum in Crooked Tree aims to address this blind spot. We discuss how cultural sustainability, collaborative partnerships, and the role of education have shaped this heritage-oriented project. Working with local teachers, we produced exhibit content that augments the national social studies curriculum. Archaeology and museum education offer object-based learning geared for school-age children and provide a powerful means of promoting cultural vitality, and a more inclusive consideration of Belizean history and cultural heritage practices and perspectives.

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Han, Shuangbiao, Yuanlong Zhang, Jie Huang, Yurun Rui et Zhiyuan Tang. « Elemental Geochemical Characterization of Sedimentary Conditions and Organic Matter Enrichment for Lower Cambrian Shale Formations in Northern Guizhou, South China ». Minerals 10, n^o 9 (8 septembre 2020) : 793. http://dx.doi.org/10.3390/min10090793.

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The black shale deposited in the Niutitang Formation and its adjacent strata is considered to be a favorable source rock in northern Guizhou of south China and has become a target horizon for shale gas exploration in recent years. Based on SQ-1 and CY-1 core samples, the organic matter properties and geochemical elements were obtained through experimental analysis. Provenance, paleoredox, paleoclimate, paleoproductivity and deposition conditions were analyzed, and the sedimentary effects on organic matter enrichment were discussed. The results show that total organic carbon (TOC) is between 0.22–10.10 wt.% in SQ-1, with an average of 2.60 wt.%, and TOC is between 0.23–7.7 wt.% in CY-1, with an average of 1.45 wt.%. The geochemical data of the samples indicate that the black shale of the Niutitang Formation and adjacent strata are deposited in the tectonic background of the passive continental margin. The provenance shows moderate weathering, with hot and humid paleoenvironmental characteristics and fast deposition rate. Using multiple ancient redox indicators, it is concluded that the formation has undergone changes in the oxidizing environment and anaerobic environment during deposition. According to the (La/Yb)N value (the average value of SQ-1 is 1.23 and the average value of CY-1 is 1.26), it shows a faster deposition rate of the two wells and shortens the residence time of organic matter in the microbial degradation zone. The Babio indicates that the bottom has a high paleoproductivity when deposited. Considering the influencing factors, the paleoproductivity mainly controls the organic matter enrichment, followed by ancient redox conditions and the deposition rate. The research results provide a reference for deepening sedimentary understanding and shale gas exploration in the study area.

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Mishra, Rahul, S. P. Datta, M. C. Meena, D. Golui, K. K. Bandyopadhyay, A. Bhatia et A Chaudhary. « Geostatistical analysis of arsenic contamination in soil and comparison of interpolation techniques in Nadia district of Bengal, India ». Emergent Life Sciences Research 09, n^o 01 (2023) : 83–90. http://dx.doi.org/10.31783/elsr.2023.918390.

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The contamination of soil and water with arsenic directly or indirectly affects millions of people, particularly in Southeast Asia. Efficiently managing contaminated sites cost-effectively requires an understanding of the spatial distribution of contamination in soil. In this study, different interpolation methods, including Ordinary Kriging (OK), Inverse Distance Weighted (IDW), Radial Basis Function (RBF), and Empirical Bayesian Kriging (EBK), were evaluated in the Bengal region to determine their effectiveness in predicting the Olsen extractable As content in the soil. The study found that the mean Olsen extractable content in soil was 1.45 mg kg-1 , with a range of 0.48 to 3.57 mg kg-1 . Geostatistical analysis showed that the northern side of Nadia had relatively high contamination, while the southern side had relatively lower contamination. The Root Mean Square Error (RMSE) values of the different interpolation methods ranged from 0.52 to 0.54, with corresponding mean cross-validation (CV) values ranging from -0.005 to 0.008. The predicted minimum and maximum values of as-in soil were in close agreement with the measured values for IDW interpolation, followed by OK, RBF, and EBK. The study found that IDW consistently provided the most precise predictions of pollution in the soil throughout space. These findings have significant implications for managing contamination in the Nadia West Bengal and other regions facing similar challenges.

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Klaus, Haagen D., Walter Alva, Steve Bourget et Luis Chero. « BIOLOGICAL DISTANCE PATTERNS AMONG THE NORTHERN MOCHE LORDS : DENTAL PHENOTYPES AND POLITICAL ORGANIZATION IN ANCIENT PERU ». Latin American Antiquity 29, n^o 4 (26 septembre 2018) : 696–717. http://dx.doi.org/10.1017/laq.2018.46.

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Between AD 100 and 800, the Moche culture emerged on the north coast of Peru. Diverse debates surround the nature of Moche territorial and political centralization, sociopolitical identities, and the internal social diversity of Moche society. Here we address some of these issues in a biodistance study based on phenotypic variation of inherited dental traits within and between 36 individuals in the royal tombs of Sipán (Lambayeque valley), Úcupe (Zaña valley), and Dos Cabezas (Jequetepeque valley). Metric and nonmetric dental trait data were analyzed using hierarchical cluster and R-matrix analyses. The results independently indicate that the highest-level Sipán and Dos Cabezas lords likely represented different endogamous kin groups, while limited gene flow occurred between groups of Moche lower nobility between the Lambayeque and Jequetepeque regions. Although biology and material cultural link the Lord of Úcupe to Dos Cabezas, many objects in his tomb demonstrate his participation the world of the Sipán elites. These Moche lords were, on some levels, bioculturally interconnected. Nonetheless, the data broadly lend support to a “many Moches” model of sociopolitical structure, further casting doubt on earlier one-dimensional visions of a centralized hegemonic Moche polity.

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Bier, Lionel. « The Lower Theatre at Balboura ». Anatolian Studies 40 (décembre 1990) : 69–79. http://dx.doi.org/10.2307/3642797.

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Amongst the standing remains of Greco-roman Balboura in northern Lycia are those of two theatres (Fig. 1). The smaller and better preserved clings to the steep south slope of the acropolis hill close to the line of the Hellenistic city's defence wall. The reports of early travellers provide little useful information about the monument, concerned as they are more with Balboura's rich epigraphic material than with her architecture. Spratt and Forbes, who visited the site in 1842 during their archaeological survey of the area, wrote a brief account, and nearly half a century later Petersen and Von Luschan published without comment a single photograph of the stage building's fine retaining wall showing its heavily bossed polygonal stones and its buttresses of squared blocks. No detailed picture was available, however, until the appearance in 1969 of the second volume of de Bernardi Ferrero's monumental survey of the ancient theatres in Asia Minor.The second theatre, located in a rocky bay in the hillside at the edge of the valley three hundred metres to the south, has attracted even less attention, and understandably so, for its remains consist of little more than the foundations for the stage building which lie half buried beneath earth and debris. De Bernardi Ferrero has published several photographs but no drawings. Her brief description concentrates on the system of arches supporting the pavement of the proscenium, an unusual feature for which she cites several parallels in the area.

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Reeder-Myers, Leslie, Jon M. Erlandson, Daniel R. Muhs et Torben C. Rick. « Sea level, paleogeography, and archeology on California's Northern Channel islands ». Quaternary Research 83, n^o 2 (mars 2015) : 263–72. http://dx.doi.org/10.1016/j.yqres.2015.01.002.

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Sea-level rise during the late Pleistocene and early Holocene inundated nearshore areas in many parts of the world, producing drastic changes in local ecosystems and obscuring significant portions of the archeological record. Although global forces are at play, the effects of sea-level rise are highly localized due to variability in glacial isostatic adjustment (GIA) effects. Interpretations of coastal paleoecology and archeology require reliable estimates of ancient shorelines that account for GIA effects. Here we build on previous models for California's Northern Channel Islands, producing more accurate late Pleistocene and Holocene paleogeographic reconstructions adjusted for regional GIA variability. This region has contributed significantly to our understanding of early New World coastal foragers. Sea level that was about 80-85 m lower than present at the time of the first known human occupation brought about a landscape and ecology substantially different than today. During the late Pleistocene, large tracts of coastal lowlands were exposed, while a colder, wetter climate and fluctuating marine conditions interacted with rapidly evolving littoral environments. At the close of the Pleistocene and start of the Holocene, people in coastal California faced shrinking land, intertidal, and subtidal zones, with important implications for resource availability and distribution.

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G C, SATYANARAYANA, NAIDU C V, RAO D V BHASKAR, UMAKANTH N et NAVEENA N. « Onset of northeast monsoon over South Peninsular India ». MAUSAM 71, n^o 3 (3 août 2021) : 503–12. http://dx.doi.org/10.54302/mausam.v71i3.51.

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The onset dates of the northeast monsoon over South Peninsular India are determined using the wind data at 850 hPa and 200 hPa, OLR, mean sea level pressure data for the domain 40° E to 120° E, 0° to 40° N. These three data sets are sourced from NCEP/NCAR reanalysis daily data sets. Further the daily grid point (0.25° Lat. × 0.25° Long.) rainfall data over India from Indian Meteorological Department is considered for delineation of rainfall pattern. The total length of the data of the above mentioned parameters is 21 years (1994 to 2014). Pentad distributions of the above parameters for the domain considered are prepared for examining the circulation patterns and rainfall activity. The pentads taken for the study are from 55th (28th September - 2nd October) pentad to 65th (17-21 November) pentad. In the determination of the northeast monsoon over South Peninsular India, the following points are considered: (i) The persistence of the northeasterlies at 850 hPa level, (ii) Occurrence of the rainfall over the South Peninsular India, (iii) Presence of east-west oriented trough [Intertropical Convergence Zone (ITCZ)] in the lower latitudes from Ethiopia region to Malaysia region passing through South Arabian Sea, southern region of South Peninsular India and South Bay of Bengal, (iv) The presence of low pressure over the southwest Bay of Bengal at the surface, (v) Persistence of a high pressure zone in northern latitudes of India (extending from the Saudi Arabia/Jordan region to the Head Bay of Bengal running through North Arabian Sea, Gujarat and Orissa), (vi) Presence of subtropical ridge at 200 hPa level around 17.5° N, (vii) Presence of north-south ridge over theeastern parts of China and (viii) Presence of relatively low OLR values over South Peninsular India when compared to the northern latitudes. If any pentad satisfies the above points, the middle date of the pentad is considered as the date of onset of northeast monsoon over South Peninsular India. If any pentad satisfies all the points except point number 2, importance is given to the persistence of northeasterlies and the middle date of the pentad will be declared as the onset date. By following the criteria, the dates of onset of northeast monsoon are determined for the latest 21 years. These dates are compared with those of the India Meteorological Department.

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HUANG, DIYING, JIAN GAO, CHONG DONG, YITONG SU, YANZHE FU, XINRAN LI, YUMING LIU et CHENYANG CAI. « Late Triassic fossil insects from the Laohugou Formation of northern China (Qinhuangdao, Hebei Province) ». Palaeoentomology 2, n^o 2 (5 avril 2019) : 183–91. http://dx.doi.org/10.11646/palaeoentomology.2.2.8.

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Triassic insect fossils from China are very limited. Here we report on numerous insect fossils discovered in the Upper Triassic Laohugou Formation at Heishanyao, Qinhuangdao, Hebei Province. These fossils are represented mainly by forewings of cockroaches and coleopteran elytra. The insect assemblage is most similar to that from the Upper Triassic Momonoki Formation of Japan. Fossils of the Laohugou Formation have been poorly known, so our discovery of new fossil insects bear significance for understanding the biota and sedimentary environment of this formation. The Mesozoic stratigraphic division in the Liujiang Basin has been controversial, and the usage of stratigraphic units has been inconsistent. Here we refine the stratigraphic sequence, from the bottom to the top, of the Upper Triassic Laohugou Formation, the Lower-Middle Jurassic Yaopo Formation, the Upper-Middle Jurassic Longmen Formation, the Upper Jurassic Tiaojishan Formation, and the Lower Cretaceous Zhangjiakou Formation. The Laohugou Formation is scattered in various basins in western Liaoning and northern Hebei, with the lower part mostly characterized by thick layers of complex conglomerates, suggesting a regional tectonic uplift. There is a sedimentary discontinuity between the Laohugou Formation and the Yaopo/Beipiao Formation, reflecting the uplifting activities during the late Late Triassic-early Early Jurassic in eastern China. The Laohugou Formation is overlaying on various ancient strata, representing the first regional unconformity of the northeastern margin of the North China Craton.

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