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A new Bergeria(Flemingitaceae) from the Mississippian of Xinjiang,NW China and its evolutionary implications

Journal of Palaeogeography 2019年第1期8卷 89-98页

作者： Ru Feng ashalata d’rozario Jian-Wei Zhang School of Urban and Environment Science Huaiying Normal University Xinjiang Institute of Ecology and Geography Chinese Academy of Science department of Botany Narasinha Dutt College

A new Bergeria(Lepidodendrales, Flemingitaceae), B. wenquanensis sp. nov., is described in this paper, typically characterized by the longest and elongated leaf cushions ever found. The specimen, collected from the Mississippian of Wenquan County, Xinjiang Uygur Autonomous Region, China, is represented by a fossil stem about two meters long, with distinct leaf cushions. The genus Bergeria has usually been assigned to partially decorticated Lepidodendron stems. Although Cathaysian Lepidodendron have been extensively reported in China, most of them were found in the central, eastern and southern parts of the country, rarely in northwestern China. This new species is so far the westernmost record and the most isolated representative from the Cathaysian Lepidodendron *** on the distribution of the Cathaysian Lepidodendron during the Mississippian, most of the species were in the South China Plate near the Equator, while the new species is discrete in the north, far from the Equator. According to the spatiotemporal distribution of Cathaysian Lepidodendron, this genus appeared during the Mississippian, a period which was represented by rather few species, it flourished and expanded northwards during the Pennsylvanian, taking the north block of the South China Plate as the center. Since the Cisuralian to the Guadalupian, the genus became gradually sparser in all areas of distribution, probably due to strong climate change. during the Lopingian, the genus migrated southwards to the South China block and had a broader distribution range again, and it became extinct to the end of this interval. The new species is also significant for the evolution of Lepidodendron leaf cushions. during the Mississippian, the primitive species of Lepidodendron usually had narrow, fusiform leaf cushions, while the Pennsylvanian or Permian species were more variable in shape of leaf cushions, from inverted water-drop, rhomboidal, hexagonal, trapeziform to horizontal rhomboidal.

关键词： Cathaysian flora Bergeria Lepidodendron Mississippian Xinjiang

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A New Species of the Extinct Genus Schizolepis from the Jurassic daohugou Flora,Inner Mongolia,China with Special Reference to the Fossil diversity and Evolutionary Implications

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 471-481页

作者： ZHANG Jianwei ashalata d＇rozario YAO Jianxin WU Zhenjie WANG Lijun Institute of Geology Chinese Academy of Geological Science Beijing 100037 China department of Botany Narasinha Dutt College 129 Bellilious Road Howrah 711 101 India College of Ethnology and Sociology South Central University for Nationalities Wuhan 430074 Hubei China

Schizolepis daohugouensis sp. nov. is described from the Jurassic sediments of daohugou flora, from Ningcheng County, Inner Mongolia Autonomous Region, China. The female cone is slender, cylindrical in shape, seed scale complexes are loosely and helically arranged on the cone axis at intervals of 3-5 mm. The seed scales are bilobed and divided almost from the base; the scales have no evident petiole but an articulation at the region of attachment to the cone axis. Each lobe of the seed scales is oval in shape, widest at the lower middle part; lobes are obtusely pointed with entire margins. Bract scale is fan shaped. Based on the records of Schizolepis, this is the first report of the occurrence of female cone of Schizolepis with the seed scales, the winged seeds and vegetative branches preserved together in the Jurassic deposits. The new discovery provides evidence that confirms the phylogenetic position of Schizolepis to the extant Pinaceae.

关键词： daohugou Jurassic Pinaceae Schizolepis China

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Plant Remains from an Archaeological Site as Indicators of Vegetation and Agricultural Practice Between(3 320±400) and(2 080±80) yr BP in Gangetic West Bengal,India

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Journal of Integrative Plant Biology 2006年第6期48卷 628-641页

作者： Ruby Ghosh Subir Bera ashalata d'rozario Manju Banerjee Supriyo Chakraborty department of Botany University of Calcutta 35 Ballygunge Circular RoadKolkata 700019India Narasinha dutt College 129 Bellilious Road Howrah 711101India Radiocarbon dating Laboratory Birbal Sahni Institute of Palaeobotany 53 University RoadLucknow 226007India

diverse plant remains recovered from an archaeological site of Chslcollthlc-Early Historic age in the Bhalrabdanga area of Pakhanna （latitude 23°25′N, longitude 87°23′E）, situated on the west bank of the damodar river, Bankura district, West Bengal, India, include food grains, wood charcoals, and palynomorphs. Radiocarbon dating of the recovered biological remains reveal the age of the site as （3 320 ± 400） to （2 080± 80） yr BP. The food grains were Identified as Oryza sativa L. and Vigna mungo L, and seeds of Brassica cf. campestris L. were also found; these indicate the agricultural practice and food habits of the ancient people living at Pakhanna from the Chalcolithlc to the Early Historic period. Sediments Including plant remains have been broadly divided into two zones, considering archaeological findings and radiocarbon dating. Analysis of the plant remains （I.e, wood charcoals and palynomorphs） in addition to cultivated food grains has revealed that a rich vegetation cover existed in this area, with a prevailing tropical and humid climate, comprising the timber-yielding plants Shores sp., Terminalia sp., and Tamarindus sp., with undergrowths of diverse shrubs and herbs during the Chalcolithic period （zone I） dated （3 320 ± 400） yr BP. Comparatively poorer representation and frequency of plant remains Indicate a drier climate during the Early Historic period （zone Ⅱ） dated as （2 110 ± 340） to （2 080 ± 80） yr BP. Comparisons of the archaeobotanical data recovered from the Chalcollthic and Early Historic period and also a principle components analysis Indicate a change In the climate of the area from tropical and humid at （3 320 ± 400） yr BP to tropical and drier conditions at （2 110 ± 340） to （2 080 ± 80） yr BP. The present-day tropical, dry deciduous vegetation of the area suggests that climate change has occurred in the area since the contemporaneous past. The plant remains database has been utilized to reconstruct the settlement pattern of the community livi

关键词： agriculture archaeological site culture, India Pakhanna, plant remains vegetation West Bengal.

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Epidermal characters of Tamarix L.(Tamaricaceae) from Northwest China and their taxonomic and palaeogeographic implications

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Journal of Palaeogeography 2018年第2期7卷 179-196页

作者： Jian-Wei Zhang ashalata d'rozario Shi-Min duan Xi-Yong Wang Xiao-Qing Liang Bo-Rong Pan Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences department of Botany Narasinha Dutt College Turpan Eremophytes Botanical Garden Chinese Academy of Sciences School of Resource and Environmental Sciences Yuxi Normal University

The taxonomical position of species of the genus Tamarix(Tamaricaceae) has been criticized because of their gross morphological similarities(such as slender, smooth and reddish-brown branches,grey-green foliage and scale leaves), and their systematic relationships remain unclear. In this paper, the leaf epidermal features of 17 species from China are studied based on the micro-morphological characters of the epidermal cells, stomata, salt glands, papillae and epidermal hairs. According to the studies, the leaf epidermal features, together with the character of the flower, are taxonomically clearly distinct. The establishment of Tamarix albiflonum is consolidated. Tamarix korolkowi and Tamarix ramosissima have minimal differences in epidermal characters, and the former is suggested to be a junior synonym. Tamarix ramosissima, Tamarix tarimensis, Tamarix arceuthoides and Tamarix hohenackeri are most similar with respect to their leaf epidermis; considering the common morphological features, habit, distribution and especially the hybridization, it is suggested that these four species are closely genetically related and that the variations among them are probably intraspecific. The new taxonomical evidence indicates the occurrence of13 species and four variants in China. Presently, Tamarix is a typical plant of arid and semi-arid regions, but its Eocene ancestors lived in warm and humid climates in the coastal areas of the ancient Mediterranean ***, the papillae or epidermal hairs, which are outgrowths of the outer epidermal cells facilitating the leaf to respond to water stress and commonly seen in the plants growing in arid or semi-arid areas rather than the plants in warm and humid climates, are of relatively recent origin in Tamarix. The primitive species lack papillae or epidermal hairs, while in evolved species these structures are abundant. Based on the ecological adaptations of the epidermal features, the palaeogeographic implications of Tamarix in the Late

关键词： Anatomy Arid region Epidermis Ecological adaptation Phylogenetic evolution Tamarix Northwest China

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Plant diversity, population structure, and regeneration status in disturbed tropical forests in Assam, northeast India

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Journal of Forestry Research 2013年第4期24卷 715-720页

作者： Gitamani dutta ashalata devi department of Environmental Science Tezpur University

We investigated the plant population structure and the phy- tosociological and regeneration status in two disturbed tropical forests in Assam Province, the Hojai Reserve Forest and Kumorakata Reserve Forest. A total of 166 species （80 trees, 20 shrubs and 66 herbs） of 136 genera and 63 families were recorded in both study sites. The disturbance index at the two sites, Kumorakata Reserve Forest and Hojai Reserve Forest, were recorded at 11.4% and 3.70% respectively. Reverse J-shaped population curve and exploitation of tree species in higher girth classes were recorded at both study sites. In the girth classes （10-30 cm, 30-60 cm, 60-90 cm and 90-120 cm in size） the percentage of cut stump density was higher than the percentage of individual living trees. The 18% （Kumorakata Reserve Forest） and 7% （Hojai Reserve Forest） spe- cies were recorded as not regenerating. Illegal felling and over-exploitation of forest resources may lead to species-specific changes in the population structure and can alter the future structure and composi- tion of the forests.

关键词： plant diversity regeneration disturbance population struc-ture Assam India

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An application of blended amendments in monsoon rice field

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Ecological Processes 2017年第1期6卷 373-380页

作者： Madhumita Ghosh ashalata devi department of Environmental Science Tezpur UniversityP.O-784028 NapaamIndia

Introduction:Rice is the main food crop of the world,and the cultivation of rice crop during the monsoon season is hard due to the rain-induced *** from this,farmers in north-eastern regions of India often implement improper crop management leading to poor ***,the development of suitable management practices under improved varieties of rice become essential for increasing rice productivity,improving soil quality status and reducing methane ***:The aim of the study was to investigate the variation in soil properties,crop growth and methane emission under the application of an inorganic fertiliser as well as its mixtures with both inorganic and plant *** such an attempt,a field-based experiment was conducted with the rice variety Chandrama during 2015 in slightly acidic soil having sandy loam *** amendments,*** and NPK,blended separately with magnesium sulphate,fresh neem(Azadirechta indica)leaves,used tea(Camellia sinensis ***)leaves,and fresh karanj(Pongamia glabra)leaves were used for the study with four replications ***:Application of NPK separately with the leaves of neem,tea and karanj separately at the onset of monsoon season markedly affected the soil porosity and the water-holding capacity of the ***,in comparison with sole NPK fertilisation,a significance increase in soil organic matter accumulation(2.48±0.10%)was seen only for karanjblended NPK while magnesium sulphate-blended NPK showed the lowest methane emission(0.30±0.01 mg/m2/h).The rice plants grown on karanj-blended NPK soil showed the highest yield(0.560±0.01 kg/m2)among the five ***:It was found that only the karanj leaves blended NPK could significantly improve the soil organic matter and increase rice yield without intensifying methane emission,while magnesium sulphate blended with NPK could significantly reduce methane emission in the flooded rice paddy soil at 0.5 t/ha application level but

关键词： Inorganic fertiliser Leaves of plants Soil properties Rice yield Methane emission

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Snapshot imaging of ultrashort electron bunches

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Light(Science & Applications) 2024年第7期13卷 1226-1228页

作者： Andreas döpp Ludwig-Maximilian-Universität München Am Coulombwall 185748GarchingGermany Max Planck Institut für Quantenoptik Hans-Kopfermann-Strasse 1Garching85748Germany

New measurements combine spatial and temporal information from optical transition radiation to estimate the three-dimensional structure of electron bunches from a laser wakefield accelerator.

关键词： ultrashort Snapshot electron

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Influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 563-580页

作者： N.HUMNEKAR d.SRINIVASACHARYA department of Mathematics National Institute of TechnologyWarangal 506004TelanganaIndia

The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is *** darcyBrinkman model is used to characterize the fluid flow dynamics in porous *** analytical solutions are obtained for the unidirectional and completely developed *** on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is *** eigenvalue problem is then solved by the spectral ***,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing *** results show that increasing the darcy number,the Lewis number,the dufour parameter,or the Soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the ***,the flow is the most unstable when the channel is vertically oriented.

关键词： nanofluid inclined channel variable viscosity linear stability double dif-fusion porous medium

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Improved Leap-frog Method for Time-domain Fault Location

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 670-674页

作者： Izudin džafić Rabih A.Jabr Faculty of Electrical Engineering University of SarajevoSarajevo 71000Bosnia and Herzegovina department of Electrical and Computer Engineering American University of BeirutBeirut 11072020Lebanon IEEE

The partial differential equation(PdE)solution of the telegrapher is a promising fault location method among time-domain and model-based *** research works have shown that the leap-frog process is superior to other explicit methods for the PdE ***,its implementation is challenged by determining the initial conditions in time and the boundary conditions in *** letter proposes two implicit solution methods for determining the initial conditions and an analytical way to obtain the boundary conditions founded on the signal *** results show that the proposal gives fault location accuracy superior to the existing leap-frog scheme,particularly in the presence of harmonics.

关键词： Fault location leap-frog partial differential equation time-domain analysis transmission line

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decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and dFT calculations

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Journal of Environmental Sciences 2024年第1期135卷 433-448页

作者： Xiang Meng Pierre désesquelles Lejin Xu department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science&TechnologyWuhan 430074China CNRS Laboratoire de Physique des Gaz et des PlasmasUniversitéParis-SaclayOrsay 91405France State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The treatment and disposal of radioactive waste are presently facing great *** ion exchange resins have become a focus of attention due to their high production and serious environmental *** this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(dFT)*** prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the *** meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain *** C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily *** is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring *** decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons.

关键词： Cationic exchange resin Statistical molecular fragmentation model density functional theory Hydroxyl radical decomposition mechanism

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