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 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 Soil Organic Carbon and Feeding the Future written by Rattan Lal and published by CRC Press. This book was released on 2022-01-18 with total page 491 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil organic matter (SOM) is a highly reactive constituent of the soil matrix because of its large surface area, high ion exchange capacity, enormous affinity for water due to hygroscopicity, and capacity to form organo-mineral complexes. It is an important source and sink of atmospheric CO2 and other greenhouse gases depending on climate, land use, soil and crop management, and a wide range of abiotic and biotic factors, including the human dimensions of socioeconomic and political factors. Agroecosystems are among important controls of the global carbon cycle with a strong impact on anthropogenic or abrupt climate change. This volume of Advances in Soil Sciences explains pedological processes set-in-motion by increases in SOM content of depleted and degraded soils. It discusses the relationship between SOM content and critical soil quality parameters including aggregation, water retention and transport, aeration and gaseous exchange, and chemical composition of soil air. The book identifies policy options needed to translate science into action for making sustainable management of SOM as a strategy for adaptation to and mitigation of climate change. Features: Relates soil organic matter stock to soil processes, climate parameters, vegetation, landscape attributes Establishes relationships between soil organic matter and land use, species, and climate Identifies land use systems for protecting and restoring soil organic matter stock Links soil organic matter stock with the global carbon cycle for mitigation of climate change Part of the Advances in Soil Sciences series, this volume will appeal to agricultural, environmental, and soil scientists demonstrating the link between soil organic matter stock and provisioning of critical ecosystem services for nature and humans.
Download or read book Advances and Technology Development in Greenhouse Gases Emission Capture and Conversion written by Mohammad Reza Rahimpour and published by Elsevier. This book was released on 2024-07-01 with total page 565 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approx.730 pages Introduces different sources of greenhouse gases emission Describes different methods for controlling greenhouse gases emission Includes geo-engineering methods for decreasing greenhouse gases emission
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 Yedoma Permafrost Landscapes as Past Archives Present and Future Change Areas written by Lutz Schirrmeister and published by Frontiers Media SA. This book was released on 2022-06-30 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Potentials for Nutrient Cycling in Wet Tundra Soils Barrow Alaska written by S. Norrell and published by . This book was released on 1973 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Microbial Communities of Polar and Alpine Soils written by Laura Zucconi and published by Frontiers Media SA. This book was released on 2021-11-10 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Arctic Ecosystem written by Jerry Brown and published by Stroudsburg, Pa. : Dowden, Hutchinson & Ross ; [New York] : Distributed world-wide by Academic Press. This book was released on 1980 with total page 614 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of a series of volumes reporting results of research under the International Biological Program concerning the ecology of the Alaskan arctic coastal plain.
Download or read book Organic Carbon Transformation and Mercury Methylation in Tundra Soils from Barrow Alaska written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dataset includes information on soil labile organic carbon transformation and mercury methylation for tundra soils from Barrow, Alaska. The soil cores were collected from high-centered polygon (trough) at BEO and were incubated under anaerobic laboratory conditions at both freezing and warming temperatures for up to 8 months. Soil organic carbon including reducing sugars, alcohols, and organic acids were analyzed, and CH4 and CO2 emissions were quantified. Net production of methylmercury and Fe(II)/Fe(total) ratio were also measured and provided in this dataset.
Download or read book Fertilizer Abstracts written by and published by . This book was released on 1975 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soil Chemical Aspects of Plant Nutrition in Alpine Tundra at Eagle Summit Alaska written by Lee Stuart (Program director) and published by . This book was released on 1983 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Size fractionation and Characterization of Cryoturbated Soil Organic Matter in Arctic Tundra Alaska written by Chunhao Xu and published by . This book was released on 2005 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Recent studies indicated a second layer of organic matter often accumulates in the lower active layer and upper permafrost in arctic tundra soils due to cryoturbation. The objective of this study is to characterize cryoturbated organic matter by the combination of physical size-fractionation approaches with modern analytical techniques. The results of elemental composition (C, N), stable isotope (13C, 15N), radiocarbon age (14C), and molecular fingerprints (Py-GC/MS) analysis indicated cryoturbated organic matters are little humified and highly bioavailable. SOM (soil organic matter) associated with fine sand size particles was considered to be the organic carbon pool most sensitive to the changing climate. Clay minerals stabilize less humifed organic matter than those in temperate and tropical soils. The bioavailable soluble organics extracted from cryoturbated organic matter were found to have significant long-term accumulated effects on carbon cycling. The similar molecular compositions between cryoturbated and surface organic matter suggest vegetation covers haven't changed since the early Holocene. Furthermore, the quality of SOM in moist acidic tundra is higher than that of wet nonacidic tundra. With the deepening active layer followed by thawing permafrost, cryoturbated organic matter could reenter the biogeochemical cycles in the Arctic, resulting in a positive feedback to climate change"--Leaf iii.
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 Bacterial Biomass and Nitrogen Transformation in Arctic Tundra Soils Near Barrow Alaska written by Mary Hope Silides Johnston and published by . This book was released on 1975 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soil Organisms and Decomposition in Tundra Proceedings of The Meeting Alaska August 1973 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 Biogeochemical Cycles written by Katerina Dontsova and published by John Wiley & Sons. This book was released on 2020-04-14 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elements move through Earth's critical zone along interconnected pathways that are strongly influenced by fluctuations in water and energy. The biogeochemical cycling of elements is inextricably linked to changes in climate and ecological disturbances, both natural and man-made. Biogeochemical Cycles: Ecological Drivers and Environmental Impact examines the influences and effects of biogeochemical elemental cycles in different ecosystems in the critical zone. Volume highlights include: Impact of global change on the biogeochemical functioning of diverse ecosystems Biological drivers of soil, rock, and mineral weathering Natural elemental sources for improving sustainability of ecosystems Links between natural ecosystems and managed agricultural systems Non-carbon elemental cycles affected by climate change Subsystems particularly vulnerable to global change The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals. Book Review: http://www.elementsmagazine.org/archives/e16_6/e16_6_dep_bookreview.pdf
