Theme 1: Origin of Biosphere and Evolution of Geo-Biological Systems…9
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(2016), Volume 4, Issue 2, 77-90
ISSN 2320-5407 International Journal of Advanced Research (2016), Volume 4, Issue 2, 77-90 Journal homepage: http://www.journalijar.com INTERNATIONAL JOURNAL OF ADVANCED RESEARCH RESEARCH ARTICLE LICHENOMETRIC DATING CURVE AS APPLIED TO GLACIER RETREAT STUDIES IN THE HIMALAYAS. Gaurav K. Mishra, Santosh Joshi and Dalip K. Upreti. Lichenology Laboratory, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow- 226001. Manuscript Info Abstract Manuscript History: The study critically favours the importance of lichens in estimating palaeoclimatic events and its use in depicting the future discretion regarding Received: 14 December 2015 Final Accepted: 19 January 2016 glacier retreat. Besides the various lichenometric studies carried out in Indian Published Online: February 2016 Himalayan region, the world-wide classical work of different glaciologist and geologist on different applications of lichenometry is also well focused. Key words: The study also highlights the benefits, restrains, and drawbacks associated Lichens, lichenometry,glacier with the lichenometry. Being a globally accepted biological technique retreat,India. particular emphasis is given on the need of innovative approach in implementation of lichenometry in Indian Himalayan region. *Corresponding Author Gaurav K. Mishra. Copy Right, IJAR, 2016,. All rights reserved. Introduction:- Lichens are slow growing organisms and take several years to get established in nature. Lichens are a unique group of plants, comprising of two micro-organisms, fungus (mycobiont), an organism capable of producing food via photosynthesis and alga (photobiont). These photobionts are predominantly members of the chlorophyta (green algae) or cynophyta (blue-green algae or cynobacteria). The peculiar nature of lichens enables them to colonize variety of substrate like rock, boulders, bark, soil, leaf and man-made buildings. -
Esa Publications
number 172 | 4th quarter 2017 bulletin → united space in europe European Space Agency The European Space Agency was formed out of, and took over the rights and The ESA headquarters are in Paris. obligations of, the two earlier European space organisations – the European Space Research Organisation (ESRO) and the European Launcher Development The major establishments of ESA are: Organisation (ELDO). The Member States are Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, ESTEC, Noordwijk, Netherlands. Luxembourg, the Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland and the United Kingdom. Slovenia is an Associate Member. Canada ESOC, Darmstadt, Germany. takes part in some projects under a cooperation agreement. Bulgaria, Cyprus, Malta, Latvia, Lithuania and Slovakia have cooperation agreements with ESA. ESRIN, Frascati, Italy. ESAC, Madrid, Spain. In the words of its Convention: the purpose of the Agency shall be to provide for and to promote, for exclusively peaceful purposes, cooperation among European EAC, Cologne, Germany. States in space research and technology and their space applications, with a view to their being used for scientific purposes and for operational space applications ECSAT, Harwell, United Kingdom. systems: ESEC, Redu, Belgium. → by elaborating and implementing a long-term European space policy, by recommending space objectives to the Member States, and by concerting the policies of the Member States with respect to other national -
A Critique of Phanerozoic Climatic Models Involving Changes in The
Earth-Science Reviews 56Ž. 2001 1–159 www.elsevier.comrlocaterearscirev A critique of Phanerozoic climatic models involving changes in the CO2 content of the atmosphere A.J. Boucot a,), Jane Gray b,1 a Department of Zoology, Oregon State UniÕersity, CorÕallis, OR 97331, USA b Department of Biology, UniÕersity of Oregon, Eugene, OR 97403, USA Received 28 April 1998; accepted 19 April 2001 Abstract Critical consideration of varied Phanerozoic climatic models, and comparison of them against Phanerozoic global climatic gradients revealed by a compilation of Cambrian through Miocene climatically sensitive sedimentsŽ evaporites, coals, tillites, lateritic soils, bauxites, calcretes, etc.. suggests that the previously postulated climatic models do not satisfactorily account for the geological information. Nor do many climatic conclusions based on botanical data stand up very well when examined critically. Although this account does not deal directly with global biogeographic information, another powerful source of climatic information, we have tried to incorporate such data into our thinking wherever possible, particularly in the earlier Paleozoic. In view of the excellent correlation between CO2 present in Antarctic ice cores, going back some hundreds of thousands of years, and global climatic gradient, one wonders whether or not the commonly postulated Phanerozoic connection between atmospheric CO2 and global climatic gradient is more coincidence than cause and effect. Many models have been proposed that attempt to determine atmospheric composition and global temperature through geological time, particularly for the Phanerozoic or significant portions of it. Many models assume a positive correlation between atmospheric CO2 and surface temperature, thus viewing changes in atmospheric CO2 as playing the critical role in r regulating climate temperature, but none agree on the levels of atmospheric CO2 through time. -
Metagenomic Profiling of the Methane-Rich Anoxic Waters of Lake Untersee As an Ocean Worlds Analog
Ocean Worlds (2019) 6025.pdf METAGENOMIC PROFILING OF THE METHANE-RICH ANOXIC WATERS OF LAKE UNTERSEE AS AN OCEAN WORLDS ANALOG. N. Y. Wagner1, A. S. Hahn2,3, D. Andersen4, C. Roy5, M. B. Wilhelm6, M. Vanderwilt1, S. S. Johnson1, 1 Johnson Biosignatures Lab, Georgetown University, 2 Department of Microbiology and Immunology, University of British Columbia, 3 Koonkie Cloud Services Inc., 4 Carl Sagan Center, SETI Institute, 5 Department of Geography, McGill Uni- versity, 6NASA Ames Research Center. Untersee, Central Dronning Maud Land, East Antarcti- Introduction: Under ocean worlds conditions on En- ca.” Limnology and Oceanography, vol. 51, no. 2, 2006, celadus, it has been shown that biological methane produc- pp.1180–1194, [4] Bevington, James, et al. “The Thermal tion may be possible [1]. Also, the possibility of methano- Structure of the Anoxic Trough in Lake Untersee, Antarcti- genesis on Europa has been hypothesized [2]. Given the po- ca.”Antarctic Science, vol. 30, no. 6, 2018, pp. 333–344. tential for methanogenesis on the icy moons of Saturn and Jupiter, we are exploring the range of life capable of survival in an extremely methane-rich terrestrial analog. Lake Untersee as an Ocean Worlds Analog: Lake Un- tersee is located in Queen Maud Land, East Antarctica. It is perennially covered in 3 meters of ice and closed off from the outside world by the Anuchin glacier. The lake contains Figure 1. Depth profile of the aerobic and anoxic basins of an aerobic basin and anoxic basin (Figure 1). The aerobic Lake Untersee [4]. basin has been measured to be up to 169m deep with a con- stant temperature of 0.25˚C. -
Lichen Life in Antarctica a Review on Growth and Environmental Adaptations of Lichens in Antarctica
Lichen Life in Antarctica A review on growth and environmental adaptations of lichens in Antarctica Individual Project for ANTA 504 for GCAS 08/09 Lorna Little Contents Antarctic Vegetation ...............................................................................................................................3 The Basics of Lichen Life .........................................................................................................................4 Environmental Influences .......................................................................................................................7 Nutrients .............................................................................................................................................7 Water Relations and Temperature .....................................................................................................7 UV‐B Radiation and Climate Change Effects.......................................................................................8 Variations in Lichen Growth and Colonisation......................................................................................10 Growth rate.......................................................................................................................................10 Case Studies of Antarctic Lichens .....................................................................................................13 Colonisation ......................................................................................................................................15 -
Lichens of Alaska's South Coast
Lichens of Alaska’s South Coast United States Forest Service R10-RG-190 Department of Alaska Region July 2011 Agriculture WHAT IS A LICHEN? Lichens are specialized fungi that “farm” algae as a food source. Unlike molds, mildews, and mushrooms that parasi ze or scavenge food from other organisms, the fungus of a lichen cul vates ny algae and / or blue-green bacteria (called cyanobacteria) within the fabric of interwoven fungal threads that form the body of the lichen (or thallus). The algae and cyanobacteria produce food for themselves and for the fungus by conver ng carbon dioxide and water into sugars using the sun’s energy (photosynthesis). Thus, a lichen is a combina on of two or some mes three organisms living together. Perhaps the most important contribu on of the fungus is to provide a protec ve habitat for the algae or cyanobacteria. The green or blue-green photosynthe c layer is o en visible between two white fungal layers if a piece of lichen thallus is torn off . Most lichen-forming fungi cannot exist without the photosynthe c partner because they have become dependent on them for survival. But in all cases, a fungus looks quite diff erent in the lichenized form compared to its free-living form. HOW DO LICHENS REPRODUCE? Lichens sexually reproduce with frui ng bodies of various shapes and colors that can o en look like miniature mushrooms. These are called apothecia (Fig. 1) and contain spores that germinate and Figure 1. Apothecia, fruiting grow into the fungus. Each bodies fungus must fi nd the right photosynthe c partner in order to become a lichen. -
Algal Toxic Compounds and Their Aeroterrestrial, Airborne and Other Extremophilic Producers with Attention to Soil and Plant Contamination: a Review
toxins Review Algal Toxic Compounds and Their Aeroterrestrial, Airborne and other Extremophilic Producers with Attention to Soil and Plant Contamination: A Review Georg G¨аrtner 1, Maya Stoyneva-G¨аrtner 2 and Blagoy Uzunov 2,* 1 Institut für Botanik der Universität Innsbruck, Sternwartestrasse 15, 6020 Innsbruck, Austria; [email protected] 2 Department of Botany, Faculty of Biology, Sofia University “St. Kliment Ohridski”, 8 blvd. Dragan Tsankov, 1164 Sofia, Bulgaria; mstoyneva@uni-sofia.bg * Correspondence: buzunov@uni-sofia.bg Abstract: The review summarizes the available knowledge on toxins and their producers from rather disparate algal assemblages of aeroterrestrial, airborne and other versatile extreme environments (hot springs, deserts, ice, snow, caves, etc.) and on phycotoxins as contaminants of emergent concern in soil and plants. There is a growing body of evidence that algal toxins and their producers occur in all general types of extreme habitats, and cyanobacteria/cyanoprokaryotes dominate in most of them. Altogether, 55 toxigenic algal genera (47 cyanoprokaryotes) were enlisted, and our analysis showed that besides the “standard” toxins, routinely known from different waterbodies (microcystins, nodularins, anatoxins, saxitoxins, cylindrospermopsins, BMAA, etc.), they can produce some specific toxic compounds. Whether the toxic biomolecules are related with the harsh conditions on which algae have to thrive and what is their functional role may be answered by future studies. Therefore, we outline the gaps in knowledge and provide ideas for further research, considering, from one side, Citation: G¨аrtner, G.; the health risk from phycotoxins on the background of the global warming and eutrophication and, ¨а Stoyneva-G rtner, M.; Uzunov, B. -
Further Investigations on Rhizocarpon of North-Eastern Iran: R
Hindawi Publishing Corporation Journal of Mycology Volume 2014, Article ID 528041, 5 pages http://dx.doi.org/10.1155/2014/528041 Research Article Further Investigations on Rhizocarpon of North-Eastern Iran: R. geographicum Mahroo Haji Moniri Department of Biology, Faculty of Sciences, Islamic Azad University, Mashhad Branch, Mashhad 917 56 89 119, Iran Correspondence should be addressed to Mahroo Haji Moniri; h [email protected] Received 15 January 2014; Accepted 7 April 2014; Published 29 April 2014 Academic Editor: Simona Nardoni Copyright © 2014 Mahroo Haji Moniri. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Morphology, anatomy, secondary chemistry, ecology, and distribution of Rhizocarpon geographicum (Rhizocarpaceae, lichenized Ascomycota) in north-eastern Iran are investigated and discussed. 1. Introduction the elevation of the sites ranges from 1340 to 1880 m. Over 537 Rhizocarpon thalli were investigated of which 311 (58%) Iran has an exceptional variety of biomes which has resulted belong to R. geographicum. As a result much new information in an extensive diversity in many organism groups including became available on the species of Rhizocarpon [11–13]. Mor- lichens. The history of lichenological exploration in north- phological and anatomical characteristics of the thalli and eastern Iran is fairly extensive, dating back to the middle fruiting bodies were examined with a stereomicroscope and a of the twentieth century [1, 2]. Since 2004, however, the light microscope. Preparations were made in distilled water, investigations in the present Khorasan provinces have much 10% KOH and KI. -
Abstracts from the Fifth European Workshop on Astrobiology EANA
International Journal of Astrobiology 5 (1): 67–88 (2006) Printed in the United Kingdom 67 doi:10.1017/S1473550406002849 f 2006 Cambridge University Press Abstracts from the Fifth European Workshop on Astrobiology EANA – European Astrobiology Network Association 10–12 October 2005 Budapest, Hungary Early Stars and Stellar Environments Oral Presentations The UV radiation environment in the Solar System Setting a scene: before another Earth will be found A. Hanslmeier(1), M. Vazquez(2), H. Lammer(3), M. Khodachenko(3) E. Szuszkiewicz(1,2), J. C. B. Papaloizou(3,4) (1) Institut fu¨r Physik, Geophysik Astrophysik Meteorologie, Univ.- (1) Institute of Physics, University of Szczecin, Poland; (2) Centre for Platz 5, A-8010 Graz, Austria; (2) Instituto de Astrofisica de Canarias, Advanced Studies in Astrobiology and Related Topics, Szczecin, C/Vı´aLa´ctea s/n, E-38200, La Laguna, Tenerife, Spain; (3) Austrian Poland; (3) Astronomy Unit, Queen Mary, University of London, Academy of Science Space Research Institute Schmiedlstraße 6, A-8042 England; (4) Department of Applied Mathematics and Theoretical Graz, Austria Physics, Centre for Mathematical Sciences, Cambridge, England The UV radiation environment in the Solar System is dominated of The increasing number of extrasolar multi-planet systems, their diver- course by the Sun. Since the early Sun radiated more intensely in the sity, and dynamical complexities provide a strong motivation to study short wavelength range, the influence of this radiation to the early the evolution and stability of such systems. One of the most important planets and to the formation of early planetary atmospheres as well as features connected with planetary system evolution is the occurrence of to the evolution of life on Earth and possibly other planets has to be mean motion resonances, which may relate to conditions at the time of considered in detail. -
Lichenometry and the Biology of the Lichen Genus Rhizocarpon
1 Invited Review 2 3 4 LICHENOMETRIC DATING (LICHENOMETRY) AND THE BIOLOGY OF 5 THE LICHEN GENUS RHIZOCARPON: CHALLENGES AND FUTURE 6 DIRECTIONS 7 8 9 Richard A. Armstrong 10 11 12 13 14 Dept. of Vision Sciences, Aston University, Birmingham B4 7ET, United Kingdom, 15 E-mail: [email protected] 16 1 17 ABSTRACT. Lichenometric dating (lichenometry) involves the use of lichen 18 measurements to estimate the age of exposure of various substrata. Because of low 19 radial growth rates [RaGR] and considerable longevity, species of the crustose lichen 20 genus Rhizocarpon have been the most useful in lichenometry. The primary 21 assumption of lichenometry is that colonization, growth, and mortality of 22 Rhizocarpon are similar on surfaces of known and unknown age so that the largest 23 thalli present on the respective faces are of comparable age. This review describes the 24 current state of knowledge regarding the biology of Rhizocarpon and considers two 25 main questions: (1) to what extent does existing knowledge support this assumption 26 and (2) what further biological observations would be useful both to test its validity 27 and to improve the accuracy of lichenometric dates? A review of the Rhizocarpon 28 literature identified gaps in knowledge regarding early development, the growth 29 rate/size curve, mortality, regeneration, competitive effects, colonization, and 30 succession on rock surfaces. The data suggest that these processes may not be 31 comparable on different rock surfaces, especially in regions where growth rates and 32 thallus turnover are high. In addition, several variables could differ between rock 33 surfaces and influence maximum thallus size including rate and timing of 34 colonization, RaGR, environmental differences, thallus fusion, allelopathy, thallus 35 mortality, colonization, and competition. -
Dating of Little Ice Age Glacier Fluctuations in the Tropical Andes
C. R. Geoscience 337 (2005) 1311–1322 http://france.elsevier.com/direct/CRAS2A/ External Geophysics, Climate and Environment (Glaciology) Dating of Little Ice Age glacier fluctuations in the tropical Andes: Charquini glaciers, Bolivia, 16◦S Antoine Rabatel a,∗, Vincent Jomelli b, Philippe Naveau c, Bernard Francou d, Delphine Grancher e a UR Great-Ice/IRD, LGGE, 54, rue Molière, 38402 Saint-Martin-d’Hères, France b UR Great-Ice/IRD, Maison des sciences de l’eau, BP 64501, 34394 Montpellier, France c Laboratoire des sciences du climat et de l’environnement, CNRS, 91191 Gif-sur-Yvette, France d UR Great-Ice/IRD, CP 9214, La Paz, Bolivie e Laboratoire de géographie physique, CNRS, 1, place Aristide-Briand, 92195 Meudon, France Received 19 October 2004; accepted after revision 5 July 2005 Available online 24 August 2005 Presented by Ghislain de Marsily Abstract Fluctuations of the Charquini glaciers (Cordillera Real, Bolivia) have been reconstructed for the Little Ice Age (LIA) from a set of 10 moraines extending below the present glacier termini. A lichenometric method using the Rhizocarpon geographicum was used to date the moraines and reconstruct the main glacier fluctuations over the period. The maximum glacier extent occurred in the second half of the 17th century, followed by nearly continuous retreat with three interruptions during the 18th and the 19th centuries, marked by stabilisation or minor advances. Results obtained in the Charquini area are first compared with other dating performed in the Peruvian Cordillera Blanca and then with the fluctuations of documented glaciers in the Northern Hemisphere. Glacier fluctuations along the tropical Andes (Bolivia and Peru) were in phase during the LIA and the solar forcing appears to be important during the period of glacier advance. -
Extremophile Hunt Begins 8 February 2008
Extremophile Hunt Begins 8 February 2008 Hoover, "is that you don't have to have a 'Goldilocks' zone with perfect temperature, a certain pH level, and so forth, for life to thrive." Researchers have found microbes living in ice, in boiling water, in nuclear reactors. These "strange" extremophiles may in fact be the norm for life elsewhere in the cosmos. "With our research this year, we hope to identify some new limits for life in terms of temperature and pH levels. This will help us decide where to search for life on other planets and how to recognize alien life if we actually find it." Spirochaeta americana, extreme-loving microbes from California's Mono Lake. Hoover et al discovered them Hoover has already made some new friends in cold during a previous extremophile-hunting expedition. places. Earlier Hoover teams have found new species and genera of anaerobic microbial extremophiles in the ice and permafrost of Alaska, Siberia, Patagonia, and Antarctica. A team of scientists has just left the country to explore a very strange lake in Antarctica; it is filled "I found one extremophile in penguin guano," with, essentially, extra-strength laundry detergent. recalls Hoover. "When I stooped to pick it up, Jim No, the researchers haven't spilled coffee on their Lovell, my research partner then, said, 'What the lab coats. They are hunting for extremophiles -- heck are you doing now, Richard?' But it paid off." tough little creatures that thrive in conditions too extreme for most other living things. Most incredible, though, was the revelation a few years ago that some extremophiles the researchers Antarctica's Lake Untersee, fed by glaciers, always found in an Alaskan tunnel actually came to life as covered with ice, and very alkaline, is one of the the ice around them melted.