Microbial Communities of Polar and Alpine Soils PDF Download

Author: Laura Zucconi
Publisher: Frontiers Media SA
ISBN: 288971618X
Category : Science
Languages : en
Pages : 187

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Author: Anna Simpson
Publisher:
ISBN:
Category :
Languages : en
Pages : 160

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Book Description
The alpine Pacific Northwest is an environment of stunning beauty and environmental extremes, with acidic, low-nutrient soils, snow cover often exceeding 4-5 m, and snow periods occasionally exceeding 9 months out of the year. Nitrogen (N) deposition from increasing urbanization and intensive agriculture can cause changes in alpine soil chemistry and plant species abundance and increase leaching of inorganic N into streams and lakes. In the state of Washington has already exceeded critical N loads for shifts in alpine lichen communities (Geiser et al., 2010) and alpine lake microbiota (Sheibley et al., 2014). The effects of climate change, which could include earlier snowmelt, increased fall rains, and even the complete disappearance of permanent snowfields and glaciers, threaten to exacerbate effects of N deposition even further by causing changes in plant phenology and increasing decomposition of soil organic matter. In this study I used fertilizer treatment of 0, 3, 5 and 10 kg NH4NO3-N ha−1 yr−1 to simulate increased N deposition at three alpine meadows of the Pacific Northwest at Mount Rainier, North Cascades and Olympic National Parks. Using the indicator of increased soil NO3-N availability to alpine plants and microbes, I define the empirical critical load upper limit for Pacific Northwest alpine meadows to be 6 kg N ha−1 yr−1. I found that increased fall microbial N uptake in these meadows appears to serve as a buffer for inorganic N loss with fall rains. No increases in plant species were observed during the course of the study. In soils with available soil inorganic N from slow depolymerization and mineralization, N pollution accumulated in plots with higher N and greater abundance of forbs and graminoid species. In very N-limited soils, N deposition was evenly dispersed among plant communities. I also sampled the soil microbial communities of barren, permanent snowfield soils at Mount Rainier and North Cascades National Parks. I used 16SrRNA metagenomic amplicon sequencing to examine the differences between the microbial communities in samples taken in dry soil that had only been covered by seasonal snow, and soil underneath permanent snowpack. Photoautotrophic bacteria were not present in samples taken under snowpack and comprised less than 1% of reads in samples taken from exposed soils. Soils were dominated by Deltaproteobacteria from the genus Anaeromyxobacter, which were particularly abundant under snowpack, and a number of bacteria from the phylum Gemmatimonadetes. Overall, permanent snowfield soils of the Pacific Northwest contain diverse heterotrophic and chemoautolithotrophic communities of bacteria but have very low overall biomass, comparable to barren soils sampled in the Himalayas. Soil bacterial communities probably depend at least partially on organic matter from atmospheric deposition and carbon fixation from seasonal snow algae for survival in this harsh environment.

Author: Susanne Liebner
Publisher: Walter de Gruyter GmbH & Co KG
ISBN: 311049390X
Category : Science
Languages : en
Pages : 323

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The cryosphere stands for environments where water appears in a frozen form. It includes permafrost, glaciers, ice sheets, and sea ice and is currently more affected by Global Change than most other regions of the Earth. In the cryosphere, limited water availability and subzero temperatures cause extreme conditions for all kind of life which microorganisms can cope with extremely well. The cryosphere’s microbiota displays an unexpectedly large genetic potential, and taxonomic as well as functional diversity which, however, we still only begin to map. Also, microbial communities influence reaction patterns of the cryosphere towards Global Change. Altered patterns of seasonal temperature fluctuations and precipitation are expected in the Arctic and will affect the microbial turnover of soil organic matter (SOM). Activation of nutrients by thawing and increased active layer thickness as well as erosion renders nutrient stocks accessible to microbial activities. Also, glacier melt and retreat stimulate microbial life in turn influencing albedo and surface temperatures. In this context, the functional resilience of microbial communities in the cryosphere is of major interest. Particularly important is the ability of microorganisms and microbial communities to respond to changes in their surroundings by intracellular regulation and population shifts within functional niches, respectively. Research on microbial life exposed to permanent freeze or seasonal freeze-thaw cycles has led to astonishing findings about microbial versatility, adaptation, and diversity. Microorganisms thrive in cold habitats and new sequencing techniques have produced large amounts of genomic, metagenomic, and metatranscriptomic data that allow insights into the fascinating microbial ecology and physiology at low and subzero temperatures. Moreover, some of the frozen ecosystems such as permafrost constitute major global carbon and nitrogen storages, but can also act as sources of the greenhouse gases methane and nitrous oxide. In this book we summarize state of the art knowledge on whether environmental changes are met by a flexible microbial community retaining its function, or if the altered conditions also render the community in a state of altered properties that affect the Earth’s element cycles and climate. This book brings together research on the cryosphere’s microbiota including permafrost, glaciers, and sea ice in Arctic and Antarctic regions. Different spatial scales and levels of complexity are considered, spanning from ecosystem level to pure culture studies of model microbes in the laboratory. It aims to attract a wide range of parties with interest in the effect of climate change and/or low temperatures on microbial nutrient cycling and physiology.

Author: Rosa Margesin
Publisher: Springer
ISBN: 3319570579
Category : Science
Languages : en
Pages : 685

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Cold adaptation includes a complex range of structural and functional adaptations at the level of all cellular constituents, and these adaptations render cold-adapted organisms particularly useful for biotechnological applications. This book presents the most recent knowledge of (i) boundary conditions for microbial life in the cold, (ii) microbial diversity in various cold ecosystems, (iii) molecular cold adaptation mechanisms and (iv) the resulting biotechnological perspectives.

Author: David Anthony Pearce
Publisher: Frontiers Media SA
ISBN: 2889669556
Category : Science
Languages : en
Pages : 181

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Author: Asim K. Bej
Publisher: CRC Press
ISBN: 1420083880
Category : Science
Languages : en
Pages : 424

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Pollution has accompanied polar exploration since Captain John Davis' arrival on the Antarctic continent in 1821 and has become an unavoidable consequence of oil spills in our polar regions. Fortunately, many of the organisms indigenous to Polar ecosystems have the ability to degrade pollutants. It is this metabolic capacity that forms the basis fo

Author: Rosa Margesin
Publisher: Springer Science & Business Media
ISBN: 3540693718
Category : Science
Languages : en
Pages : 346

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Book Description
Most of the Earth’s biosphere is characterized by low temperatures. Vast areas (>20%) of the soil ecosystem are permanently frozen or are unfrozen for only a few weeks in summer. Permafrost regions occur at high latitudes and also at high ele- tions; a significant part of the global permafrost area is represented by mountains. Permafrost soils are of global interest, since a significant increase in temperature is predicted for polar regions. Global warming will have a great impact on these soils, especially in northern regions, since they contain large amounts of organic carbon and act as carbon sinks, and a temperature increase will result in a release of carbon into the atmosphere. Additionally, the intensified release of the clima- relevant tracer gas methane represents a potential environmental harzard. Significant numbers of viable microorganisms, including bacteria, archaea, p- totrophic cyanobacteria and green algae, fungi and protozoa, are present in per- frost, and the characteristics of these microorganisms reflect the unique and extreme conditions of the permafrost environment. Remarkably, these microorg- isms have been reported to be metabolically active at subzero temperatures, even down to ?20°C.

Author: Don A. Cowan
Publisher: Springer
ISBN: 3642452132
Category : Science
Languages : en
Pages : 324

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This book brings together many of the world’s leading experts in the fields of Antarctic terrestrial soil ecology, providing a comprehensive and completely up-to-date analysis of the status of Antarctic soil microbiology. Antarctic terrestrial soils represent one of the most extreme environments on Earth. Once thought to be largely sterile, it is now known that these diverse and often specialized extreme habitats harbor a very wide range of different microorganisms. Antarctic soil communities are relatively simple, but not unsophisticated. Recent phylogenetic and microscopic studies have demonstrated that these communities have well established trophic structuring and play a significant role in nutrient cycling in these cold and often dry desert ecosystems. They are surprisingly responsive to change and potentially sensitive to climatic perturbation. Antarctic terrestrial soils also harbor specialized ‘refuge’habitats, where microbial communities develop under (and within) translucent rocks. These cryptic habitats offer unique models for understanding the physical and biological ‘drivers’ of community development, function and evolution.

Author: Wael N. Hozzein
Publisher: BoD – Books on Demand
ISBN: 1838800557
Category : Science
Languages : en
Pages : 164

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This book is for the students starting their research projects in the field of metagenomics, for researchers interested in the new developments and applications in this field; and for teachers involved in teaching this subject. The book is divided into three sections as indicated from its title, namely; the basics of metagenomics, metagenomic analysis, and applications of metagenomics. It covers the basics of metagenomics from its history and background, to the analysis of metagenomic data as well as its recent applications in different fields. The book contains excellent texts at both the introductory and advanced levels, that describe the latest metagenomic approaches and applications, from sampling to data analysis for taxonomic, environmental, and medical studies. Finally, the publication of this book was an interesting journey for me and I hope the readers will enjoy reading it.

Author: Julie Dinasquet
Publisher: Frontiers Media SA
ISBN: 2889455130
Category :
Languages : en
Pages : 315

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Marine and freshwater polar environments are characterized by intense physical forces and strong seasonal variations. The persistent cold and sometimes inhospitable conditions create unique ecosystems and habitats for microbial life. Polar microbial communities are diverse productive assemblages, which drive biogeochemical cycles and support higher food-webs across the Arctic and over much of the Antarctic. Recent studies on the biogeography of microbial species have revealed phylogenetically diverse polar ecotypes, suggesting adaptation to seasonal darkness, sea-ice coverage and high summer irradiance. Because of the diversity of habitats related to atmospheric and oceanic circulation, and the formation and melting of ice, high latitude oceans and lakes are ideal environments to investigate composition and functionality of microbial communities. In addition, polar regions are responding more dramatically to climate change compared to temperate environments and there is an urgent need to identify sensitive indicators of ecosystem history, that may be sentinels for change or adaptation. For instance, Antarctic lakes provide useful model systems to study microbial evolution and climate history. Hence, it becomes essential and timely to better understand factors controlling the microbes, and how, in turn, they may affect the functioning of these fragile ecosystems. Polar microbiology is an expanding field of research with exciting possibilities to provide new insights into microbial ecology and evolution. With this Research Topic we seek to bring together polar microbiologists studying different aquatic systems and components of the microbial food web, to stimulate discussion and reflect on these sensitive environments in a changing world perspective.