Download or read book Decomposition of organic matter in tundra written by O W (Bill) Heal and published by . This book was released on 1974 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pathways of Anaerobic Organic Matter Decomposition in Tundra Soils from Barrow Alaska written by and published by . This book was released on 2015 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arctic tundra soils store a large quantity of organic carbon that is susceptible to decomposition and release to the atmosphere as methane (CH4) and carbon dioxide (CO2) under a warming climate. Anaerobic processes that generate CH4 and CO2 remain unclear because previous studies have focused on aerobic decomposition pathways. To predict releases of CO2 and CH4 from tundra soils, it is necessary to identify pathways of soil organic matter decomposition under the anoxic conditions that are prevalent in Arctic ecosystems. Here molecular and spectroscopic techniques were used to monitor biological degradation of water-extractable organic carbon (WEOC) during anoxic incubation of tundra soils from a region of continuous permafrost in northern Alaska. Organic and mineral soils from the tundra active layer were incubated at -2, +4, or +8°C for up to 60 days to mimic the short-term thaw season. Results suggest that, under anoxic conditions, fermentation converted complex organic molecules into simple organic acids that were used in concomitant Fe-reduction and acetoclastic methanogenesis reactions. Nonaromatic compounds increased over time as WEOC increased. Organic acid metabolites initially accumulated in soils but were mostly depleted by day 60 because organic acids were consumed to produce Fe(II), CO2, and CH4. We conclude that fermentation of nonprotected organic matter facilitates methanogenesis and Fe reduction reactions, and that the proportion of organic acids consumed by methanogenesis increases relative to Fe reduction with increasing temperature. As a result, the decomposition pathways observed in this study are important to consider in numerical modeling of greenhouse gas production in the Arctic.
Download or read book Geochemical Drivers of Organic Matter Decomposition in Arctic Tundra Soils written by and published by . This book was released on 2015 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climate change is warming tundra ecosystems in the Arctic, resulting in the decomposition of previously-frozen soil organic matter (SOM) and release of carbon (C) to the atmosphere; however, the processes that control SOM decomposition and C emissions remain highly uncertain. In this study, we evaluate geochemical factors that influence anaerobic production of carbon dioxide (CO2) and methane (CH4) in the active layers of four ice-wedge polygons. Surface and soil pore waters were collected during the annual thaw season over a two-year period in an area containing waterlogged, low-centered polygons and well-drained, high-centered polygons. We report spatial and seasonal patterns of dissolved gases in relation to the geochemical properties of Fe and organic C as determined using spectroscopic and chromatographic techniques. Iron was present as Fe(II) in soil solution near the permafrost boundary but enriched as Fe(III) in the middle of the active layer, similar to dissolved aromatic-C and organic acids. Dissolved CH4 increased relative to dissolved CO2 with depth and varied with soil moisture in the middle of the active layer in patterns that were positively correlated with the proportion of dissolved Fe(III) in transitional and low-centered polygon soils but negatively correlated in the drier flat- and high-centered polygons. These results suggest that microbial-mediated Fe oxidation and reduction influence respiration/fermentation of SOM and production of substrates (e.g., low-molecular-weight organic acids) for methanogenesis. As a result, we infer that geochemical differences induced by water saturation dictate microbial products of SOM decomposition, and Fe geochemistry is an important factor regulating methanogenesis in anoxic tundra soils.
Download or read book Soil Organisms and Decomposition in Tundra written by Alfred John Holding and published by . This book was released on 1974 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fennoscandian Tundra Ecosystems written by Frans Emil Wielgolaski and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: The term Fennoscandia is used to denote Finland and the Scandinavian peninsula, which comprises Norway and Sweden and sometimes also neigh bouring districts of the USSR. The western part of the Scandinavian peninsula is mountainous with peaks mostly within the range 1000-2000 m above sea level. Permafrost is not usually found in the southern districts of these alpine zones, but occurs in the northeastern part of Fennoscandia in mire, even at a low elevation. If tundra is defined as areas of permafrost, only very limited regions of Fennoscandia could be included. However, in the present volumes, we have used the word tundra in a broader sense as approximating areas with mean annual air 0 temperature below 0 C at meteorological standard height (1.5-2 m); it is often used in this sense in North America. This usage allows all alpine zones to be included, along with the subalpine birch zone and certain open subarctic woodland ("forest tundra" in Russian usage).
Download or read book Litter Decomposition a Guide to Carbon and Nutrient Turnover written by and published by Academic Press. This book was released on 2005-11-22 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: Litter Decomposition describes one of the most important processes in the biosphere - the decay of organic matter. It focuses on the decomposition process of foliar litter in the terrestrial systems of boreal and temperate forests due to the greater amount of data from those biomes. The availability of several long-term studies from these forest types allows a more in-depth approach to the later stages of decomposition and humus formation. Differences between the decay of woody matter and foliar litter is discussed in detail and a different pattern for decomposition is introduced. While teachers and students in more general subjects will find the most basic information on decomposition processes in this book, scientists and graduate students working on decomposition processes will be entirely satisfied with the more detailed information and the overview of the latest publications on the topic as well as the methodological chapter where practical information on methods useful in decomposition studies can be found. Abundant data sets will serve as an excellent aid in teaching process and will be also of interest to researchers specializing in this field as no thorough database exists at the moment. Provides over 60 tables and 90 figures Offers a conceptual 3-step model describing the different steps of the decomposition process, demonstrating changes in the organic-chemical structure and nutrient contents Includes a synthesis of the current state of knowledge on foliar litter decomposition in natural systems Integrates more traditional knowledge on organic matter decomposition with current problems of environmental pollution, global change, etc. Details contemporary knowledge on organic matter decomposition
Download or read book Principles of Terrestrial Ecosystem Ecology written by F Stuart Chapin III and published by Springer Science & Business Media. This book was released on 2006-04-10 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt: Features review questions at the end of each chapter; Includes suggestions for recommended reading; Provides a glossary of ecological terms; Has a wide audience as a textbook for advanced undergraduate students, graduate students and as a reference for practicing scientists from a wide array of disciplines
Download or read book Structure and Function of an Alpine Ecosystem written by William D. Bowman and published by Oxford University Press. This book was released on 2001-04-26 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Alpine Tundra.
Download or read book Tundra Ecosystems written by International Biological Programme and published by CUP Archive. This book was released on 1981 with total page 864 pages. Available in PDF, EPUB and Kindle. Book excerpt: Brings together the results of research programmes in Austria, Canada, U.S.A., Finland, Norway, Sweden, Greenland, U.K., Ireland, U.S.S.R. and the Antarctic describing tundra and related ecosystems in a comparative manner. Includes sections on the abiotic, plant production and fauna components, the decomposer cycle and the utilisation and conservation of tundra.
Download or read book Ecology written by Robert E. Ricklefs and published by Macmillan. This book was released on 2000 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt: See publisher description:
Download or read book Nutrient Cycling in Terrestrial Ecosystems written by Petra Marschner and published by Springer Science & Business Media. This book was released on 2007-05-01 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive overview of nutrient cycling processes and their importance for plant growth and ecosystem sustainability. The book combines fundamental scientific studies and devised practical approaches. It contains contributions of leading international authorities from various disciplines resulting in multidisciplinary approaches, and all chapters have been carefully reviewed. This volume will support scientists and practitioners alike.
Download or read book Effects of Thermokarst Slumps on Ecosystem Carbon and Nitrogen in Upland Arctic Tundra written by Andres Felipe Baron Lopez and published by . This book was released on 2012 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results suggest that the undisturbed tundra soils contain large pools of buried organic matter that has been protected from decomposition by cold temperatures that inhibit microbial activity. RTS, as an abrupt spatial and temporal disturbance, have the capacity to rearrange massive quantities of surface soil and the C and N it contains, modifying the ecosystem soil and vegetation composition dynamics. RTS acts as a generator of new niches for plant colonization, exposes rich-nutrient mineral soil layers, mobilizes sediment to receiving waters, and modifies the local topography. RTS dynamics through time have the capacity to substantially alter the form and function in upland arctic tundra. Understanding the effects of RTS on ecosystem C and N dynamics offers a unique opportunity to establish links between climate change and the ecological impacts of changing disturbance regimes.
Download or read book Forest Ecosystems in the Alaskan Taiga written by K. van Cleve and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: The information presented in this book is the result of combined research efforts of scientists at the University of Alaska, Fairbanks, the Institute of Northern Forestry, USDA Forest Service, and the Systems Ecology Research Group, San Diego State University. The objective of the volume is to present a synthetic overview of structure and function of taiga forest ecosystems in interior Alaska. The data base for this work has appeared in earlier published articles including the special issue of the Canadian Journal of Forest Research Volume 13:5 (1983). Stimulus for this book was a conference held in Fairbanks from June 10-14, 1983. The papers presented at the conference were fore runners of the chapters in this book. We invited 19 scientists from North America and England to critique our research and synthesis efforts. Six of these people were asked to write introductory chapters for each section of the book. Formal presentation sessions, combined with field trips to research sites, introduced the invitees to the primary and secondary successional ecosystems with which we were dealing. A major wildfire, only 24 km from the University campus, was contained the week prior to the conference and one field trip provided graphic evidence of fire impact in subarctic forests. The conference conveners regretted that it was not possible to host a similar meeting during synthesis efforts in mid-January.
Download or read book Ecology of Arctic Environments written by Sarah J. Woodin and published by Cambridge University Press. This book was released on 1997-08 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: Once thought of as a pristine environment, it is now all too apparent that the Arctic is a sink for pollutants transported northwards over long distances in the atmosphere and oceans, and is also likely to be subject to major climate change as a result of global warming. Many ecologists are currently seeking to further our understanding of how arctic ecosystems function, and to detect and predict anthropogenic changes which may occur within them. This book, resulting from a British Ecological Society Special Symposium, addresses these issues.
Download or read book Modelling Regulation of Decomposition and Related Root mycorrhizal Processes in Arctic Tundra Soils Final Report written by and published by . This book was released on 1992 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since this was the final year of this project principal activities were directed towards either collecting data needed to complete existing incomplete data sets or writing manuscripts. Data sets on Imnaviat Creek watershed basin are functionally complete and data finialized on the cellulose mineralizaiton and dust impact on soil organic carbon and phsophorus decomposition. Seven manuscripts were prepared, and are briefly outlined.
Download or read book Soil Organisms and Decomposition in Tundra written by A. J. Holding and published by . This book was released on 1974 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tundra Ecosystems written by Tammy Gagne and published by ABDO. This book was released on 2015-08-01 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt: This title will introduce readers to tundra ecosystems, the plants and animals that thrive there, its climate, its food web, any threats to it, and conservation efforts. Readers will also learn about the most well known tundras and their unique characteristics. . Aligned to Common Core Standards and correlated to state standards. Core Library is an imprint of Abdo Publishing, a division of ABDO.
