cretaceous period
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Author(s):  
Akshaya Rathore

Abstract: Dinosaur Fossils National Park Bagh has huge fossils reserves of late cretaceous period that includes Dinosaurs bones, whole dinosaurs’ nests, dinosaurs’ eggs, tree fossils, shark teeth, ammonites, bivalves, inoceramids, and other marine organisms. With the help of local researchers and forest staff over the period oftime we had collected fossils of many species. Firstly, we inventoried the fossils physically and documented each by maintaining Stock Registers. Digitizing the Stock Registers – to convert each register in excel file which includes all the details regarding that fossil. To make it more attractive and useful in future, we have created 3dmodels of at least one specimen of each fossils’ species. To have worldwide reach, we have created and hosted the website www.dinosaurfossilsnationalparkbagh.in . I


Agronomy ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 83
Author(s):  
Yuki Matuda ◽  
Arihiro Iwasaki ◽  
Kiyotake Suenaga ◽  
Hisashi Kato-Noguchi

Metasequoia glyptostroboides Hu et W.C. Cheng is one of the oldest living conifer species, and it has remained unchanged for millions of years compared to its fossils from the Cretaceous period. The species are cultivated in the parks, gardens, and roadsides in many countries. We investigated the allelopathy and allelopathic substances in fallen leaves of M. glyptostroboides. An aqueous methanol extract of the fallen leaves inhibited the growth of cress (Lepidium sativum L.), lettuce (Lactuca sativa L.), alfalfa (Medicago sativa L.), Lolium multiflorum Lam., Phleum pretense L., and Vulpia myuros (L.) C.C.Gmel. The extract was then purified by several chromatographic steps, and two allelopathic substances were isolated and determined by spectral data to be (+)-rhododendrol and 9-epi-blumenol C. The compound inhibited the growth of cress and L. multiflorum. M. glyptostroboides is a deciduous perennial tree, and accumulation of its fallen leaves occur on the soil under the trees. Therefore, those allelopathic substances in the fallen leaves may be liberated into the rhizosphere soil during the decomposition process of fallen leaves and provide a competitive advantage for M. glyptostrob through the growth inhibition of competing plant species nearby. Therefore, M. glyptostroboides is allelopathic, and (+)-rhododendrol and 9-epi-blumenol C may be contribute to the allelopathy.


Archaea ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Shaoxing Chen ◽  
Yongpei Dai ◽  
Jingwen Liu ◽  
Shimin Zhang ◽  
Feilong Chen ◽  
...  

A novel halovirus, VOLN27B, was isolated from a drill core sample taken at a depth of approximately 430 m, from a layer formed during the Cretaceous period (Anhui, China). VOLN27B infects the halophilic archaeon Halorubrum sp. LN27 and has a head-tailed morphotype with a contractile tail, typical of myoviruses. The average head diameter is 64 ± 2.0  nm, and uncontracted tails are 15 ± 1.0 × 65 ± 2.0  nm. The latent period is about 10 h. The maturing time of VOLN27B in cells of Halorubrum sp. LN27 was nearly 8 h. The adsorption time of VOLN27B on cells of Halorubrum sp. LN27 was less than 1 min. Virus particles are unstable at pH values less than 5 or when the NaCl concentration is below 12% ( w / v ). VOLN27B and Halorubrum sp. LN27 were recovered from the same hypersaline environment and provide a new virus-host system in haloarchaea.


2021 ◽  
Author(s):  
◽  
Te Amohaere Ngata-Aerengamate

<p>Phytophthora are plant pathogens, well known for devastating thousands of ecologically, culturally and economically significant plant crops worldwide. In greek Phytophthora translates directly to ‘plant destroyer’. Though it is ‘fungus-like’, Phytophthora are eukaryotic oomycetes, more closely related to brown algae and diatoms. Phytophthora have three key lifecycle stages: oospores, zoospores, and mycelia. Kauri are ancient conifer species dating back to the Cretaceous period (145 mya) and are now rapidly declining due to Kauri dieback caused by Phytophthora agathidicida. P.agathadicida causes root rot in Kauri trees and was first misidentified as P. hevave on Great Barrier Island in the early 1970s. Its origin is unknown however research argues it may have evolved from P. infestans, the pathogen that caused the Irish potato famine in 1845. For Te Āo Māori, Kauri are highly regarded tīpuna (ancestors) and Kauri Dieback is alarming to many Northern Iwi. Kauri wood and resin are highly sought and economically valuable resources. The Waipoua forest is the largest Kauri forest and the most impacted by Kauri Dieback. Over 25% of Kauri in the Waitākere ranges are either infected with P. agathadicida or are symptomatic, a percentage that is steadily increasing. A rāhui (temporary ban) was placed on the Waitākere ranges by local iwi Te Kawerau a Maki in 2018 as a preventative measure to reduce movement of P. agathadicida in soil. Apart from track closures, scrubbing and spraying equipment - before and after entering the forest - is the only tool of management. Sterigene disinfectant is the only treatment to reduce the spread of Kauri Dieback. Sterigene kills zoospores, mycelia and sporangium but is ineffective against P. agathidicida oospoores. Sexually produced oospores are responsible for the long-term survival of Phytophthora as they have a thick cell wall. The first part of this thesis examines a range of commercially available disinfectants and their efficacy against P. agathidicida oospores. These results confirm that Sterigene and/or Trigene are not effective against P. agathidicida oospores. My results also show that 2% bleach, 1% Virkon, and 70% ethanol all reduce oospore viability. Napisan also reduced oospore viability, but also interacted with the viability stains, therefore further investigations are needed. Napisan is an oxygen bleach, commercially affordable and easily accessible in supermarkets. Unlike sterigene and bleach, Napisan is safe to use on clothes, wool and soft textiles. If effective against oospores and the other lifecycle stages, Napisan could be a promising solution to help reduce the spread of Kauri Dieback.</p>


2021 ◽  
Author(s):  
◽  
Te Amohaere Ngata-Aerengamate

<p>Phytophthora are plant pathogens, well known for devastating thousands of ecologically, culturally and economically significant plant crops worldwide. In greek Phytophthora translates directly to ‘plant destroyer’. Though it is ‘fungus-like’, Phytophthora are eukaryotic oomycetes, more closely related to brown algae and diatoms. Phytophthora have three key lifecycle stages: oospores, zoospores, and mycelia. Kauri are ancient conifer species dating back to the Cretaceous period (145 mya) and are now rapidly declining due to Kauri dieback caused by Phytophthora agathidicida. P.agathadicida causes root rot in Kauri trees and was first misidentified as P. hevave on Great Barrier Island in the early 1970s. Its origin is unknown however research argues it may have evolved from P. infestans, the pathogen that caused the Irish potato famine in 1845. For Te Āo Māori, Kauri are highly regarded tīpuna (ancestors) and Kauri Dieback is alarming to many Northern Iwi. Kauri wood and resin are highly sought and economically valuable resources. The Waipoua forest is the largest Kauri forest and the most impacted by Kauri Dieback. Over 25% of Kauri in the Waitākere ranges are either infected with P. agathadicida or are symptomatic, a percentage that is steadily increasing. A rāhui (temporary ban) was placed on the Waitākere ranges by local iwi Te Kawerau a Maki in 2018 as a preventative measure to reduce movement of P. agathadicida in soil. Apart from track closures, scrubbing and spraying equipment - before and after entering the forest - is the only tool of management. Sterigene disinfectant is the only treatment to reduce the spread of Kauri Dieback. Sterigene kills zoospores, mycelia and sporangium but is ineffective against P. agathidicida oospoores. Sexually produced oospores are responsible for the long-term survival of Phytophthora as they have a thick cell wall. The first part of this thesis examines a range of commercially available disinfectants and their efficacy against P. agathidicida oospores. These results confirm that Sterigene and/or Trigene are not effective against P. agathidicida oospores. My results also show that 2% bleach, 1% Virkon, and 70% ethanol all reduce oospore viability. Napisan also reduced oospore viability, but also interacted with the viability stains, therefore further investigations are needed. Napisan is an oxygen bleach, commercially affordable and easily accessible in supermarkets. Unlike sterigene and bleach, Napisan is safe to use on clothes, wool and soft textiles. If effective against oospores and the other lifecycle stages, Napisan could be a promising solution to help reduce the spread of Kauri Dieback.</p>


Author(s):  
Methaq K. Al-Jafar ◽  
Mohanad H. Al-Jaberi

AbstractSandstone oil reserves are composed of a variety of clay minerals, including kaolinite, illite, and chlorite. These clay minerals have a significant effect of reservoir quality. The upper sandstone member (USS) of Zubair Formation is the most plentiful reservoir of the field and it’s part of a large anticline that belongs to an enormous clastic sandstone formation, from the Lower Cretaceous period. A spectral gamma-ray (SGR) log was used to identify the type of clay minerals, depositional environment, and the relationship between total organic matter with uranium concentration. SGR log indicated that USS is composed mainly of chlorite, smectite, and illite clay minerals with the presence of kaolinite as a dominant clay mineral component. Th/U ratio varies between 2.55 and 8.52 and 1.11 to 11.68 in the north and south parts of the field, respectively. The USS had a fluvially dominated, sand-rich deltaic environment based on the Th/U ratio. Furthermore, Th/K cross-plot was found that the south part was more affected by illite compared with the north part, although the presence of kaolinite.


2021 ◽  
Vol 11 (22) ◽  
pp. 10796
Author(s):  
Donghoon Seoung ◽  
Pyosang Kim ◽  
Hyeonsu Kim ◽  
Hyunseung Lee ◽  
Min Huh ◽  
...  

Mudeungsan (Mount Mudeung) is an extinct volcano located in the southwestern part of South Korea that was formed in the Late Cretaceous period. This mountain, 1187 m above sea level, is adjacent to Gwangju Metropolitan City, which has a large population (about 1.4 million) and volcanic rocks, including columnar joints, which form various types of outcrops. Although this mountain was listed as a national geopark in 2014 and a UNESCO Global Geopark in 2018, much basic research has yet to be carried out. In particular, there are no mineralogical studies of volcanic rock samples despite the well-preserved variety of volcanic rocks. For this study, X-ray diffraction analysis was conducted using rock samples from Mudeungsan columnar joints known as tuff. We report that the rocks are mostly dacite, mainly composed of quartz, plagioclase, and sanidine through Rietveld quantitative analysis. In particular, α-cristobalite, a crystalline polymorph of silica, appears in the columnar joint rocks, indicating that Mudeungsan experienced an explosive eruption during the formation of the mountain.


2021 ◽  
Vol 2090 (1) ◽  
pp. 012110
Author(s):  
V P Parkhomenko

Abstract Studies indicate the mass death of a significant number of biological groups on Earth, in particular - dinosaurs, at the end of the Cretaceous period 66 million years ago. Currently, there are two main theories: large-scale volcanic eruptions and the asteroid impact that formed the Chicxulub crater (Mexico). The production of sulfur-containing gases from the Earth’s surface layers vapors during impact is considered a main source of climatic effects, as they form stratospheric sulfate aerosols that block sunlight and thus cool the Earth’s atmosphere and interfere with photosynthesis. It is presented an application of the 3-D coupled global hydrodynamic climate model of intermediate complexity, including ocean model, sea ice evolution model and energy - moisture balance atmosphere model to study this asteroid impact effects on the Earth’s climate. The model continents and ocean depths distribution corresponds to Cretaceous period. A series of calculations with different residence times and deposition times of the stratosphere aerosol have been carried out. It was found that, depending on the stratosphere aerosol time parameters, the global annual average surface air temperature decreased by 18°C - 27°C, remained below zero for 4 - 30 years, and a recovery time of more than 30 years was observed.


2021 ◽  
Vol 54 (2C) ◽  
pp. 48-58
Author(s):  
Abdulrahman Bamerni

A relatively complete Late Maastrichtian succession of the upper part of the Shiranish Formation (Upper Cretaceous) in the Duhok area is investigated for the planktic foraminiferal assemblages. This studied interval consists mainly of bluish shale, marl, and thin beds of hard marly limestone all with grey-blue color. The upper contact of the Shiranish Formation is conformable with the overlies Danian Aaliji Formation. Based on the recorded planktic foraminifera and their ranges, the studied succession is subdivided into three main biozones of the latest Maastrichtian age, these zones are Pseudoguembelina hariaensis (CF3) Interval Zone, Pseudoguembelina palpebra (CF2) Interval Zone, and Plummerita hantkeninoides (CF1) Total Range Zone. These zones show continuous and complete Upper Cretaceous sediments, which are preserved in the Bade section of the Duhok area


Insects ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 857
Author(s):  
Yuyu Wang ◽  
Ruyue Zhang ◽  
Yunlong Ma ◽  
Jing Li ◽  
Fan Fan ◽  
...  

Green lacewings are one of the largest families within Neuroptera and are widely distributed all over the world. Many species within this group are important natural predators that are widely used for the biological control of pests in agricultural ecosystems. Several proposed phylogenetic relationships among the three subfamilies of Chrysopidae have been extensively debated. To further understand the higher phylogeny as well as the evolutionary history of Chrysopidae, we newly sequenced and analyzed the low-coverage genomes of 5 species (Apochrysa matsumurae, Chrysopa pallens, Chrysoperla furcifera, Italochrysa pardalina, Nothochrysa sinica), representing 3 subfamilies of Chrysopidae. There are 2213 orthologs selected to reconstruct the phylogenetic tree. Phylogenetic reconstruction was performed using both concatenation and coalescent-based approaches, based on different data matrices. All the results suggested that Chrysopinae were a monophyletic sister group to the branch Apochrysinae + Nothochrysinae. These results were completely supported, except by the concatenation analyses of the nt data matrix, which suggested that Apochrysinae were a sister group to Chrysopinae + Nothchrysinae. The different topology from the nt data matrix may have been caused by the limited sampling of Chrysopidae. The divergence time showed that Chrysopinae diverged from Apochrysinae + Nothochrysinae during the Early Cretaceous period (144–151 Ma), while Aporchrysinae diverged from Nothochrysinae around 117–133 Ma. These results will improve our understanding of the higher phylogeny of Chrysopidae and lay a foundation for the utilization of natural predators.


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