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1.
The occurrences of Pinus L. (family Pinaceae) megafossils (cones and leaf remains) have been abundantly documented from the Cenozoic sediments of eastern Asia (Japan and China), but none has been confirmed from the Indian Cenozoic till date. Here, we describe Pinus arunachalensis Khan and Bera, sp. nov. on the basis of seed remains from the middle to late Miocene Siwalik sediments of the Dafla Formation exposed around West Kameng district in Arunachal Pradesh, eastern Himalaya. Seeds are winged, broadly oblong to oval in outline, 1.3–1.5 cm long and 0.4–0.6 cm broad (in the middle part), located basipetally and symmetrically to wing, cellular pattern of wing is seemingly undulatory and parallel with the long axis of the wing. So far, this report provides the first ever fossil record of Pinus winged seeds from India. This record suggests that Pinus was an important component of tropical-subtropical evergreen forest in the area during the Miocene and this group subsequently declined from the local vegetation probably because of the gradual intensification of MSI (monsoon index) from the Miocene to the present. We also review the historical phytogeography and highlight the phytogeographic implication of this genus.  相似文献   

2.
The data obtained from investigation of the Middle and Late Neopleistocene lake sediments in the European Subarctic Region of Russia are reported. Chirva, Rodionovo (Scklov), Sula (Mikulino), and Byzovaya (Leningrad) sediments were subject to palynological analysis and investigation of particle size distribution and mineral composition. The spore–pollen spectra of the Chirva sediments demonstrate two climatic optima: the lower optimum is dominated by the pollen of Pinus sylvestris and broad-leaved species (up to 10%); the upper optimum is dominated by Picea sp. and Pinus sylvestris, while the pollen of Picea sect. Omorica and broad-leaved species are sporadic. The Rodionovo flora is characterized by a more xerophilous composition relative to the Chirva flora and a higher pollen content of pine, birch, wormseed plants, and wormwood. The climatic optimum of the Sula interglacial is distinguished by boreal vegetation, including spruce, birch, and birch–spruce forests with sparse broad-leaved species. The Byzovaya interstadial is marked by seven stages of changes in the vegetation: from tundra and forest-tundra communities to taiga forests with some broad-leaved species. The natural climatic sedimentation conditions in the Middle and Late Neopleistocene interglacial periods are reconstructed. The mineral composition of sediments was largely formed owing to underlying deposits.  相似文献   

3.
Seven species of Calloporid (family Calloporidae Norman, 1903) Bryozoa are described from the Cenozoic sediments of the western Kachchh, Gujarat, India. Among these Planicellaria walsariensis, Dionella sp., Pyriporella charopadiensis, P. vadsariensis and Wilbertopora sp. are new and the other species viz; Crassimarginatella blandfordi and Reptoporina chhasraensis are reported for the second time from these sediments. The phylogenetic analysis suggests all the species of Calloporid bryozoans are monophyletic i.e. all of these species have common ancestor.  相似文献   

4.
Fossil leaflet impression described here as a new species Rourea miocaudata sp. nov., showing close resemblance with the modern leaflets of Rourea caudata Planch. (Connaraceae R. Br.), has been recorded from the lower part of the Siwalik sediments (Dafla Formation, middle–upper Miocene) exposed at the road-cutting section of Pinjoli area in West Kameng district, Arunachal Pradesh. The important morphological characters of the fossil are its narrow elliptic leaflet, cuneate base, long caudate apex, entire margin, eucamptodromous to brochidodromous secondary veins, presence of intersecondary veins, percurrent and reticulate tertiary veins and orthogonally reticulate quaternary veins. This is the first authentic record of the occurrence of leaflet comparable to R. caudata of Connaraceae from the Cenozoic sediments of India and abroad. At present R. caudata does not grow in India and is restricted only in southeast Asia especially in China and Myanmar. This taxon probably migrated to these southeast Asian regions after lower Siwalik sedimentation (middle–upper Miocene) due to climatic change caused by post-Miocene orogenic movement of the Himalaya. The recovery of this species and other earlier-described evergreen taxa from the same formation, suggests the existence of a tropical, warm and humid climatic conditions during the depositional period.  相似文献   

5.
Stratigraphically important ammonites Deshayesites ex gr. deshayesi (d’Orbigny, 1840), Deshayesites sp. juv., and Paradeshayesites aff. callidiscus [Casey, 1961] from lower Aptian pelagic sediments at the Verkhorech’e Village have been described and depicted. The new finds and revision of previously found ammonites allow the recognition of ammonite zones Deshayesites volgensis and Deshayesites deshayesi in the Southwestern Crimea.  相似文献   

6.
The Jahrum Formation (Upper Paleocene to Middle Eocene) is composed of carbonate and dolomitic carbonate rocks in the Zagros Basin. The Zagros is located at the boundary between the Arabian and Eurasian lithosphere plates and represent the orogenic response to a collision between Eurasia and advancing Arabia during the Cenozoic. The study area is located in the northern part of Kuh-E-Tudej, ~175 km southeast of Shiraz in the Folded Zagros Zone. The Jahrum Formation at Kuh-E-Tudej, with a thickness of 190 m, consists of medium to massive bedded limestone. The following foraminiferal index species are identified in the studied section: Fallotella alavensis, Kathina sp., Miscellanea sp., Lockhartia sp.,Orbitolites shirazeinsis, Nummulites sp., Opertorbitolites sp., Dictyoconus cf. egyptiensis, Orbitolites cf. complanatus, Dictyoconus sp., Coskinolina sp., Somalina stefaninii, Discocyclina sp., Praerhapydionina sp., Coskinolina cf. liburnica, Nummulites cf. globulus, Nummulites cf. aturicus, and Alveolina sp. The age of the studied sediments ranges from Upper Paleocene to Middle Eocene. The microbiostratigraphic studies revealed four biozones based on the foraminifers identified in the studied section.  相似文献   

7.
A rich assemblage of palynomorphs including miospores and megaspores has been recorded from the bore core no. IBKAN-2 drilled at a depth of 17.80m in Kuraloi Block-A, south-west part of the Ib-River Coalfield, Jharsuguda district, Odisha. The miofloral assemblage recovered shows prominence of cingulate, zonate, taeniate, non-striate and non saccate palynotaxa which indicate an early Triassic age and is comparable with the palynoassemblages of the same age known from the Damodar basin, India. The megaspore assemblage includes eight genera and fifteen species namely, Banksisporites karanpuraensis, B. indicus, B. utkalensis, Banksisporites sp., Barakarella pantii, Barakarella sp., Biharisporites spinosus, Biharisporites sp., Erlansonisporites triassicus, Erlansonisporites cf. erlansonii, Erlansonisporites sp. Jhariatriletes sp., Singhisporites sp., Ramispinatispora sp. and Talchirella trivedii. Records of megaspores are sparse in the early Triassic of Gondwana basins of India. The present study records the first occurrence of miospores and megaspores from the early Triassic of Mahanadi basin besides substantiating the earlier data.  相似文献   

8.
Belemnites from the lower Bathonian of the Russian Plate are revised on the basis of the study of two reference sections—Pletnyovka and Sokur quarries. The first part of the study deals with the members of the family Megateuthididae. They include eight species of the genus Barskovisella gen. nov., neoendemic to the territory of the Russian Plate and originating from high Boreal taxa—species of the genus Paramegateuthis Gustomesov, 1960, which immigrated to the Middle Russian Sea in the early Bathonian via a short-lived meridional strait. The new genus includes six new species described in the present paper—Barskovisella pseudoishmensis sp. nov., B. issae sp. nov., B. variabilis sp. nov., B. barskovi sp. nov., B. gracilis sp. nov., and B. renegata sp. nov. The beds with Barskovisella, a new belemnite-based unit, corresponding to the Oraniceras besnosovi ammonite zone and including four successive phylogenetic biohorizons well comparable in resolution with ammonite-based infrazonal subdivisions, are introduced.  相似文献   

9.
Four bacterial strains, capable of degrading diesel oil, n-alkanes or hexadecane, were isolated from soils contaminated with petroleum oil and identified. Strains of Pseudomonas sp., Pseudomonas putida TPHK-1 and Pseudomonas aeruginosa TPHK-4, were more efficient in degrading high concentrations of the hydrocarbons than the other two strains, Stenotrophomonas maltophilia TPHK-2 and Acenitobacter sp. TPHK-3. P. putida TPHK-1 exhibited tolerance to very high concentrations of heavy metals such as cadmium, lead, zinc and copper. The innate ability of P. putida TPHK-1, as evidenced by the amplified genes alkB1 and alkB2 that encode alkane hydroxylases, and cat12o and cat23o coding for catechol dioxygenase, in degrading diesel oil in the presence of heavy metals is far greater than that of the strains reported in the literature. Heavy metal tolerance coupled with rapid degradation of hydrocarbons, even at high concentrations, suggests that P. putida TPHK-1 has a great potential in remediating soils contaminated with mixtures of hydrocarbons and heavy metals.  相似文献   

10.
While multiple species of macroalgae and seagrass can benefit from elevated CO2 concentrations, competition between such organisms may influence their ultimate responses. This study reports on experiments performed with a Northwest Atlantic species of the macroalgae, Ulva, and the seagrass, Zostera marina, grown under ambient and elevated levels of pCO2, and subjected to competition with each other. When grown individually, elevated pCO2 significantly increased growth rates and productivity of Ulva and Zostera, respectively, beyond control treatments (by threefold and 27%, respectively). For both primary producers, significant declines in tissue δ13C signatures suggested that increased growth and productivity were associated with a shift from use of HCO3? toward CO2 use. When grown under higher pCO2, Zostera experienced significant increases in leaf and rhizome carbon content as well as significant increases in leaf carbon-to-nitrogen ratios, while sediments within which high CO2 Zostera were grown had a significantly higher organic carbon content. When grown in the presence of Ulva; however, above- and below-ground productivity and tissue nitrogen content of Zostera were significantly lower, revealing an antagonistic interaction between elevated CO2 and the presence of Ulva. The presence of Zostera had no significant effect on the growth of Ulva. Collectively, this study demonstrates that while Ulva and Zostera can each individually benefit from elevated pCO2 levels, the ability of Ulva to grow more rapidly and inhibit seagrass productivity under elevated pCO2, coupled with accumulation of organic C in sediments, may offset the potential benefits for Zostera within high CO2 environments.  相似文献   

11.
Smaller foraminifers from Upper Yakhtashian and Bolorian deposits of the stratotype area (Pamir, Darvaz, Tajikistan) are investigated. Four assemblages are defined. The first assemblage is from Chalaroschwagerina vulgaris-Pamirina darvasica Zone. The second assemblage found in the transitional Yakhtashian-Bolorian beds includes Globivalvulina, Palaeotextulariidae, Hemigordiidae, and Glomospira, associated with the first Pachyphloia and Langella forms. Characteristic taxa of third assemblage from the Misellina (Brevaxina) dyhrenfurthi Zone are Geinitzinidae, Globivalvulina, Palaeotextulariidae, Glomospira, and rare Pachyphloia. The forth assemblage of Hemigordiidae, Pachyphloia, Palaeotextulariidae, Geinitzinidae, Pseudoagathammina is identified in the M. (Misellina) parvicostata Zone. The assemblages were compared with concurrent analogs from China, Japan, and Russia. New species and subspecies Glomospira paleograndis sp. nov., G. darvasica sp. nov., Agathammina darvasica sp. nov., Pachyphloia darvasica sp. nov., Nodosinelloides cubanicus elongatus subsp. nov., and Hemigordius saranensis darvasicus subsp. nov. are described.  相似文献   

12.
The present megafloral assemblage recorded from the Barakar sediments of Dholpahar section along Singda rivulet near Gopal Prasad Village in Talcher Basin comprises of equisetaceous stems, Gangamopteris buriadica, Palaeovittaria kurzii and 19 species of the genus Glossopteris. Record of Gangamopteris, Palaeovittaria and many narrow mesh forms of Glosspteris viz., G. angustifolia, G. churiensis, G. communis, G. recurva, G. spatulata, G. stenoneura, G. tenuifolia, G. vulgaris and G. zeilleri from two older fossiliferous horizons demonstrates that these fossils were preserved during Lower Barakar sedimentation. The report of middle and broad mesh forms of Glossopteris viz., G. barakarensis, G. browniana, G. indica, G. intermittens, G. karharbariensis, G. nakkarea, G. oldhamii, G. taeniensis and G. retifera in the youngest fossiliferous horizons reveals that these fossils were preserved during the deposition of Upper Barakar sediments. The continuation of some of the Karharbari plant fossils in the early phase of Barakar Formation and their disappearance in the flora of Late Barakar suggests a shift in the climatic setup. Palaeoclimate and palaeovegetation of this area are also summarised in this study. Moreover, the fossil assemblages of different fossiliferous beds of Dholpahar section demonstrate the evolution of midrib and meshes in different reticulate leaves.  相似文献   

13.
The present study investigated the prevalence of pathogenic organisms (Salmonella spp, Vibrio cholerae, and Shigella spp) and their correlation to the abundance of faecal indicator organisms in water and riverbed sediments in the Apies River, South Africa. In all, 558 water and sediment samples were collected from 10 sites in the river (May 2013–February 2014) and analysed through culture and molecular (real-time PCR) techniques. Concentrations of faecal indicator organisms in sediments reached 1.39 × 105 (±standard deviation) CFU/100 mL. All three pathogens were detected in water and sediments. Pathogens were mostly detected in sediments at sites influenced either by wastewater treatment works or by informal settlements. During the wet and dry seasons (water column), a strong positive correlation was observed between E. coli and all pathogens; C. perfringens only correlated with V. cholerae. Within sediments, strong positive correlations were only observed between E. coli and Salmonella spp, E. coli and V. cholerae (dry season); E. coli and V. cholerae and E. coli and Shigella spp (wet season). No correlation was observed between sediments C. perfringens counts and all the pathogens. Thus, sediments of the Apies River harbour pathogenic organisms. Correlation between E. coli and pathogenic organisms in the sediments suggests that E. coli could also be an indicator of pathogens’ presence. However, the lack of a correlation between E. coli and some pathogens in sediments and between C. perfringens and all the pathogens highlights the need to investigate for more indicators of pathogens’ presence in this complex matrix.  相似文献   

14.
Binary mixture of Variovorax sp. BS1 and Achromobacter denitrificans degraded >99 % of 300 mg l?1 of ortho-dimethyl phthalate (DMP) within 24 h of incubation at 30 °C. Rate of degradation of DMP followed the order: A. denitrificans > binary mixture > Variovorax sp. BS1. Transient intermediate metabolites were not detected using HPLC analyses at any time points using Variovorax sp. BS1 and binary mixture. However, using pure culture of A. denitrificans, monomethyl phthalate was accumulated during the course of DMP biodegradation which disappeared with time of incubation. Binary mixture of Variovorax sp. BS1 and A. denitrificans exhibited better efficiency in terms of biodegradation of DMP as compared to either individual bacterial strain. In addition, fluorescence in situ hybridization technique was used to estimate the population dynamics of Variovorax sp. BS1 in binary mixture. A. denitrificans in mixed culture were estimated by subtracting total number of cells of Variovorax sp. BS1 from the total counts of microbial cells using an epifluorescence microscope after staining with 4′,6-diamidino-2-phenylindole. Results obtained at mid-exponential growth phase suggested the abundance of both bacterial strains as primary degraders.  相似文献   

15.
Suraqalatia brasieri n.gen., n.sp. from the family Dicyclinidae Loeblich and Tappan 1964 occurs on the Maastrichtian carbonate platform of northern Iraq. The new genus is recognizable by its large very compressed conical test, up to 55–70 mm in diameter, to 0.3–1.6 mm in thickness, planspiral cooling having very small proloculus in the initial part and later circular chambers including numerous chamberlets with an agglutinated wall. Suraqalatia brasieri n.gen., n.sp. is associated with textulariids, miliolids and rotaliids as Loftusia elongata Cox, L. morgani Douvillé, Orbitoides medius d’Archiac, O. megaloformis Papp & Kupper, O. gruenbachensis Papp, O. apiculatus Schlumberger, Omphalocyclus macroporus (Lamarck), Siderolites calcitrapoides Lamarck, Sirtina orbitoidiformis Brönnimann & Wirz. The associated macrofauna comprises large and rich giant rudists (Preradiolites sp.), other bivalves (Gryphaea sp. and Glycymeris sp.), gastropods (Acteonella sp.), echinoderms and corals. The fauna indicates shallow marine carbonate platform conditions within the Maastrichtian green house. It is also worth mentioning that the new genus has only been recorded from the Maastrichtian age.  相似文献   

16.
Micofloral study of Lameta sediments and associated sauropod coprolites in the Nand-Dongargaon basin in Maharashtra was conducted to understand the diet and habitat of sauropods. The study revealed the presence of pollen, spores, algal and fungal remains, well-preserved cuticles of Poaceae, and testate amoebae. Vegetation during Lameta included tall arboreal taxa, such as conifers (Podocarpus and Araucaria), Cycads (Cycas), Euphorian and Barringtonia and herbs and shrubs, such as Cheirolepidiaceae (Classopollis), Arecaceae (Palmaepollenites), Poaceae (Graminidites), Asteraceae (Compositoipollenites), Caryophyllaceae (Cretacaeiporites and Periporopollenites), and Acanthaceae (Multiareolites). Data suggest that the sauropods ate soft tissues of angiosperms and gymnosperms. The intake of testate amoeba, algal remains, sponge spicules, and diatoms might be through water intake.  相似文献   

17.
To evaluate the impact of invading seagrass on biogeochemical processes associated with sulfur cycles, we investigated the geochemical properties and sulfate reduction rates (SRRs) in sediments inhabited by invasive warm affinity Halophila nipponica and indigenous cold affinity Zostera marina. A more positive relationship between SRR and below-ground biomass (BGB) was observed at the H. nipponica bed (SRR = 0.6809 × BGB ? 4.3162, r 2 = 0.9878, p = 0.0006) than at the Z. marina bed (SRR = 0.3470 × BGB ? 4.0341, r 2 = 0.7082, p = 0.0357). These results suggested that SR was more stimulated by the dissolved organic carbon (DOC) exuded from the roots of H. nipponica than by the DOC released from the roots of Z. marina. Despite the enhanced SR in spring-summer, the relatively lower proportion (average, 20%) of acid-volatile sulfur (AVS) in total reduced sulfur and the strong correlation between total oxalate-extractable Fe (Fe(oxal)) and chromium-reducible sulfur (CRS = 0.2321 × total Fe(oxal) + 1.8180, r 2 = 0.3344, p = 0.0076) in the sediments suggested the rapid re-oxidation of sulfide and precipitation of sulfide with Fe. The turnover rate of the AVS at the H. nipponica bed (0.13 day?1) was 2.5 times lower than that at the Z. marina bed (0.33 day?1). Together with lower AVS turnover, the stronger correlation of SRR to BGB in the H. nipponica bed suggests that the extension of H. nipponica resulting from the warming of seawater might provoke more sulfide accumulation in coastal sediments.  相似文献   

18.
The taxonomic composition of the palynological assemblage of the Dongning Formation is supplemented. The palynological assemblage corresponds to those from the Lipovtsy Formation (Aptian) in the Razdolnaya Basin of Primorye (Russia) and the Muling Formation (Aptian) in the Jixi Basin of eastern Heilongjiang (China). It is found that the age of the Dongning Formation is Aptian. The palynological assemblage is characterized by dominance of spores of Gleicheniaceae; they are accompanied by spores of Cyatheaceae. The most important feature of the palynological assemblage of the Dongning Formation is the presence of angiosperm pollen (Tricolpites sp., T. micromunus, T. vulgaris, Retitricolpites georgiensis, R. vulgaris, Clavatipollenites hughesii, Quercites sparsus, Fraxiniopollenites variabilis).  相似文献   

19.
20.
Numerous plant remains as the imprints of lycopsid strobili and stems and the sporadic imprints of articulate stems were first found in the Upper Carboniferous deposits from the Western Slope of the Southern Urals (Karantrav Settlement area). The brief stratigraphic characteristic of the studied locality is given. The studied plant assemblage is represented by Lepidodendron ophiurus Brongniart, L. vaselgense Anikeeva et O. Orlova, sp. nov., Lepidodendron sp., Lepidostrobus tevelevii O. Orlova, Mamontov et Anikeeva, sp. nov., L. ronnaensis Bek et Oplustil, Knorria sp., Calamites sp., and Mesocalamites ramifer (Stur) Hirmer. In-situ microspores of the Lycospora type were discovered in the sporangia of some strobili of the genus Lepidostrobus. Four lycopsid species (two are new) were described.  相似文献   

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