Download or read book Holocene Peatland Carbon Accumulation Ecology and Hydrology in the Canadian James Bay Lowlands written by James Robert Holmquist and published by . This book was released on 2013 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Northern peatlands contain some of the largest terrestrial stores of organic soil carbon (C) which may grow due to increases in productivity, or decline due to higher decay under projected warming and drought scenarios. However, models of peatland growth lack data on basic peatland history for the remote James Bay Lowlands (JBL) region of Canada, as well as the relationships between climate and productivity, and the history of Holocene precipitation. This dissertation presents C accumulation, vegetative macrofossil, and proxy-climate reconstruction data from eight previously unpublished sites in the JBL, as well as synthesizes currently available data. Peatlands in the JBL initiated lagging the retreat of the Laurentide ice sheet, and the drainage of glacial lakes by an average of 2,900 years. Most of the peatlands studied initiated as mineral rich fens, which transitioned to nutrient poor bogs an average of 3,800 years after they initiated. Over the Holocene they have acted as a sink of CO2, accumulating between 71.5 and 171.2 kgC m−2, with median long-term apparent C accumulation rates (LARCA) ranging from 13.8 to 31.6 gC m−2 yr−1. Peatland C accumulation was variable within and between sites, but was driven by productivity rather than decay during the late-Holocene. The depths of late-Holocene peat deposits correlate positively with growing season length, and photosynthetically active radiation, and were negatively affected by permafrost occurrence. A single site provides evidence for a relatively dry pre-Holocene Thermal Maximum period, and a relatively wet Holocene Thermal Maximum, with a small but positive influence of water table depth on LARCA. Although there was some variation due to site-specific conditions, multiple sites indicate that the warm Medieval Climate Anomaly was a wet period in the JBL, consistent with modern precipitation anomalies, whereas the Little Ice Age was dry. The Little Ice Age may have been locally complex due to precipitation variability, or the formation of permafrost. On the short term, peatland C-stores may grow faster if temperature and seasonality changes occur within their physiological and ecological limitations. However long-term peatland stability in the area will likely be dependent on precipitation, which may fluctuate due to the positions of the Arctic and Pacific fronts, and stochastic interactions between the atmosphere and sea surface temperatures.

Download or read book Holocene Carbon Dynamics in the Patterned Peatlands of the Hudson Bay Lowland Canada written by Maara Susanna Packalen and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Paleoecological and Carbon Accumulation Dynamics of a Fen Peatland in the Hudson Bay Lowlands Northern Ontario from the Mid Holocene to Present written by Benjamin Cody O'Reilly and published by . This book was released on 2011 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pollen assemblages, peat humification and carbon:nitrogen stratigraphy were examined at high resolution in a core from a fen peatland in the Hudson Bay Lowlands, Northern Ontario, to interpret the factors that drive long-term peatland dynamics. Subtle changes in the vegetation community are evident over the record, suggesting both allogenic and autogenic influences, but a fen community appears to have been resilient to external perturbations including isostatic rebound and hydroclimatic changes between 6400 and 100 years BP. Paleoclimatic reconstructions from the fossil pollen assemblages indicate that precipitation increased 3000 years BP at the end of the Holocene Thermal Maximum, and that carbon accumulation in the fen was controlled more by effective surface moisture (precipitation) than by temperature. The pollen record suggests changes over the past century, including increases in shrub Betula, Alnus, Ambrosia, and Cyperaceae and a decrease in Sphagnum spores, consistent with the observed Pan-Arctic shrub increase.

Download or read book Carbon Accumulation in Three Ombrotrophic Peatlands of the Eastmain Region Quebec Canada written by Simon van Bellen and published by . This book was released on 2011 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Peatlands and Environmental Change written by Dan Charman and published by Wiley. This book was released on 2002-11-22 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to an awareness of peatlands as a diminishing resource, peatland conservation and rehabilitation has become an important study area. Peatlands and Environmental Change offers a new approach by considering peatlands as a whole ecosystem, and thereby provides a better understanding of the importance and the consequences of the functioning of peatlands. Contents include: * Peat and peatlands * Peat landforms and structure * Peatland hydrology and ecology * Origins and pest initiation * Peat accumulation * The peatland archive: palaeoenvironmental evidence * Autogenic change * Allogenic change * Peatland - environmental feedbacks * Values, exploitation and human impacts * Conservation management and restoration

Download or read book The Biology of Peatlands 2e written by Håkan Rydin and published by Oxford University Press. This book was released on 2013-07-18 with total page 397 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive and up to date overview of peatland ecosystems. It examines the entire range of biota present in this habitat and considers management, conservation, and restoration issues.

Download or read book Peatland stream Hydrological and Biogeochemical Connectivity in the James Bay Lowlands Ontario written by Meghan Kline and published by . This book was released on 2014 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Hudson-James Bay Lowlands are the second largest peatland dominated area on the planet, and are expected to be particularly vulnerable to future climate change. Changes in climate will affect peatland hydrology and biogeochemistry, impacting the aquatic ecosystems this region supports, however there is limited information about the hydrology and biogeochemistry of this landscape under current conditions. This thesis focuses on assessing the nature of hydrological and biogeochemical connectivity between a fen and 2nd order channel in the Central James Bay Lowland, Ontario. Specifically the study focuses on the role of preferential hydrological flowpaths in the riparian area, such as soil pipes and rivulets. We used water table-discharge relationships to examine the nature of hydrological connectivity between the fen and riparian area and identified thresholds of hydrological connectivity using these relationships. Once the storage thresholds in the near stream depression and fen have been met, peak flow can be generated in the soil pipes and rivulets, this occurs under wet antecedent conditions late in the fall. The study also identified that the riparian area is a likely dominant source of DOC and MeHg despite the extensive peatlands that dominate the upslope region, and that this area has a unique chemical signature from the fen. Furthermore late fall storm events with wet antecedent conditions were found to play an important role in solute transport from the soil pipes, with as much as>60% of the total solute load for one soil pipe occurring during a storm event which had a duration of only 17% of the monitoring period.

Download or read book The Influence of Water Table Fluctuation on Hydrarch Succession in Two Subarctic Peatlands in Eastern James Bay Quebec written by Crystal Ferguson and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Northern peatlands contain close to one-third of the world's soil carbon and changes to their ecology and hydrology play a major role in the fate of these carbon stocks and the direction of their climate feedbacks. Recent research has largely focused on modern controls on peatland development and only few studies have explored the long-term (millennial scale) synergies between peatland hydrology and ecological succession. In this study, I use two peat cores from eastern James Bay (Québec) to investigate the interaction between peatland ecology (hydrarch succession) and hydrology while considering both allogenic and autogenic drivers of peatland development. The James Bay region provides an ideal location for this study as the postglacial retreat of the vast Laurentide Ice Sheet has resulted in a unique land uplift phenomenon. This process is called glacio-isostatic rebound and has been ongoing for the last ~7000 years. One of the main consequences of glacio-isotatic uplift is rapid marine regression and the creation of a landscape gradient of increasing age (chronosequence), from the coastline to the interior, that features varying stages of peatland development. In my investigation, I use a suite of palaeoecological proxies (testate-amoeba, C/N ratios, and AMS carbon-14 chronostratigraphy) to reconstruct changes in peatland water table depth through time. This hydrological reconstruction was then compared to the reconstruction of wetland community change to determine how hydrology affects wetland successional changes (hydroseres) through time. My results indicate a nuanced role of hydrology in hydrarch succession ranging from substantial, at one site (OFL) to marginal, at the other (W55). My results further suggest that local factors (topography, drainage patterns, and local base levels) largely control peatland development in this region although large-scale drivers, such as climate and isostasy, have also played a role.

Download or read book Carbon Cycling in Northern Peatlands written by Andrew J. Baird and published by American Geophysical Union. This book was released on 2009-01-12 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 184. Carbon Cycling in Northern Peatlands examines the role that northern peatlands play in regulating the atmospheric carbon budget. It summarizes current research in four interconnected areas: large-scale peatland dynamics and carbon cycling; plant and microbial dynamics and their effect on carbon fluxes to the atmosphere; methane accumulation in, and loss from, peatlands; and water and dissolved carbon fluxes through peatlands. The volume highlights include A thorough assessment of the challenges involved in incorporating carbon cycling in northern peatlands into global climate models; A conceptual model to examine the partitioning of terminal carbon mineralization into production of CO2 and CH4; A comprehensive review of the evidence for the accumulation of methane in deep and shallow peat; and A description of the hydrologic changes induced by peat harvesting and associated challenges in restoring altered peatlands to their natural hydrologic regime. Carbon Cycling in Northern Peatlands will be of interest to research scientists and graduate and undergraduate students, particularly those who wish to know more about the role of peatlands in the global carbon cycle and their role as modifiers of climate.

Download or read book Peatlands and Climate Change written by Maria Strack and published by . This book was released on 2008 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: The International Peat Society IPS established a joint IPS Working Group on Peatlands and Climate Change in the end of the year 2005. The Working Group's task was to compile information into a summary of available knowledge to help the IPS and other actors to understand the role of peatlands and peat within the current context of global climate change.

Download or read book Wetland Carbon and Environmental Management written by Ken W. Krauss and published by John Wiley & Sons. This book was released on 2021-11-23 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explores how the management of wetlands can influence carbon storage and fluxes. Wetlands are vital natural assets, including their ability to take-up atmospheric carbon and restrict subsequent carbon loss to facilitate long-term storage. They can be deliberately managed to provide a natural solution to mitigate climate change, as well as to help offset direct losses of wetlands from various land-use changes and natural drivers. Wetland Carbon and Environmental Management presents a collection of wetland research studies from around the world to demonstrate how environmental management can improve carbon sequestration while enhancing wetland health and function. Volume highlights include: Overview of carbon storage in the landscape Introduction to wetland management practices Comparisons of natural, managed, and converted wetlands Impact of wetland management on carbon storage or loss Techniques for scientific assessment of wetland carbon processes Case studies covering tropical, coastal, inland, and northern wetlands Primer for carbon offset trading programs and how wetlands might contribute 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.

Download or read book Factors Affecting Holocene Carbon Accumulation in a Peatland in Southern Ontario written by Jennifer Ann Shiller and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Examining Large scale Peatland Patterns in the Hudson Bay Lowland written by Qianru Wang and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Peatland ecosystems are important for maintaining biodiversity, balancing the hydrological system, and regulating climate variability. The development of peatlands strongly affects the global carbon cycling, which in turn contributes to changes in both large-scale structure and community compositions. It has been proposed that peatlands can be viewed as complex adaptive systems with varying degrees of self-regulation due to a series of negative feedbacks on peatland hydrology, vegetation, nutrients, and peat accumulation. This study utilizes several classification algorithms to classify and examine the peatland patterns over a regional scale of the landscape in the Hudson Bay Lowland. Four typical types of peatlands are detected though some errors and uncertainties remain. Moreover, pattern regulations are examined and quantified by several spatial analysis methods such as image pixel area calculation, density-based spatial clustering of applications with noise, autocorrelation analysis (including river buffer test), co-location analysis, and watershed extraction (with slope calculations). The quantification results show a significant correlation between different types of peatlands and confirm that hydrological features drive regular patterns. Furthermore, this thesis opens the door for the extended modelling of large-scale two-dimensional peatland accumulation surface patterns which could help demonstrate the self-regulated properties of large-scale peatlands and explain associations between peatland horizontal successions and different environmental factors"--

Download or read book Peatlands written by I.P. Martini and published by Elsevier. This book was released on 2007-03-28 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past two decades there has been considerable work on global climatic change and its effect on the ecosphere, as well as on local and global environmental changes triggered by human activities. From the tropics to the Arctic, peatlands have developed under various geological conditions, and they provide good records of global and local changes since the Late Pleistocene.The objectives of the book are to analyze topics such as geological evolution of major peatlands basins; peatlands as self sustaining ecosystems; chemical environment of peatlands: water and peat chemistry; peatlands as archives of environmental changes; influence of peatlands on atmosphere: circular complex interactions; remote sensing studies of peatlands; peatlands as a resource; peatlands degradation, restoration, plus more. * Presents an interdisciplinary approach, with an emphasis on Earth Science, and addresses the need for intergration between subdisciplines and the developing of new approaches* Synthesizes the evolutionary, ecological, and chemical characteristics of major peatlands, as well as focuses on the environmental changes, from climate changes to surface ares changes due to human activities* Covers topical studies of worldwide interest and provides examples from many different countries

Download or read book Carbon Accumulation and Development of Peatlands Over the Holocene West Siberia Russia written by David Beilman and published by . This book was released on 2006 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Northern peatlands are storehouses for about one-third of global soil carbon, equivalent to about half of today's atmospheric carbon. The Russian Federation holds the world's greatest share of northern peatlands, and the largest complex is concentrated in the flat, low elevation plain of the West Siberia Lowland (WSL). Recent observed climate warming has been greatest at high latitudes and Arctic environmental change is predicted to continue at accelerated pace. Therefore, the past, present, and future role of peatlands in the global carbon cycle, and in a warmer Arctic, has emerged as an important question. My objective in this dissertation was to investigate the regional-scale development and carbon sequestration and accumulation history of WSL peatlands at more than 70 sites using paleoenvironmental techniques, soil carbon and nitrogen assays, AMS radiocarbon dating, and GIS analysis. Analysis of organic carbon and nitrogen content in peat reveals that values are determined mainly by fossil plant composition. These new data reveal a modest underestimation in previous estimates of the WSL peat carbon pool of 2.9 x 1015g, and the first estimate of the WSL peat nitrogen pool of 2.65 x 1015 g. The remains of fossil plant indicator species in peat profiles together with radiocarbon data show that important transitions to acidic nutrient-poor peatland conditions, which currently dominate today's WSL, have occurred mainly in the last 4000 years of the 12,000-year history of WSL peatlands. The timing of transition events coincides in near-synchonous fashion with inferred wet-climate periods of regional peatland expansion, which suggests that regional climate variation may have affected development. The reconstructed rate of carbon accumulation showed neither consistent increase nor decrease following transition. Carbon accumulation over the last 2000 years reveals considerable variation across the WSL and poor agreement with total carbon accumulation rates over the last 12,000 years. In contrast, net carbon sequestration over the last two millennia has a significant positive and non-linear relationship with modern air temperature. Extrapolation of site trends to the region suggests that about 40% of total WSL peat carbon has accumulated in the last 2000 years. Over recent millennia, the very large peatlands in the southern portion of the region are shown to have been the strongest long-term carbon sinks in the WSL.

Download or read book Biogeochemistry of Wetlands written by K. Ramesh Reddy and published by CRC Press. This book was released on 2022-09-10 with total page 926 pages. Available in PDF, EPUB and Kindle. Book excerpt: The globally important nature of wetland ecosystems has led to their increased protection and restoration as well as their use in engineered systems. Underpinning the beneficial functions of wetlands are a unique suite of physical, chemical, and biological processes that regulate elemental cycling in soils and the water column. This book provides an in-depth coverage of these wetland biogeochemical processes related to the cycling of macroelements including carbon, nitrogen, phosphorus, and sulfur, secondary and trace elements, and toxic organic compounds. In this synthesis, the authors combine more than 100 years of experience studying wetlands and biogeochemistry to look inside the black box of elemental transformations in wetland ecosystems. This new edition is updated throughout to include more topics and provide an integrated view of the coupled nature of biogeochemical cycles in wetland systems. The influence of the elemental cycles is discussed at a range of scales in the context of environmental change including climate, sea level rise, and water quality. Frequent examples of key methods and major case studies are also included to help the reader extend the basic theories for application in their own system. Some of the major topics discussed are: Flooded soil and sediment characteristics Aerobic-anaerobic interfaces Redox chemistry in flooded soil and sediment systems Anaerobic microbial metabolism Plant adaptations to reducing conditions Regulators of organic matter decomposition and accretion Major nutrient sources and sinks Greenhouse gas production and emission Elemental flux processes Remediation of contaminated soils and sediments Coupled C-N-P-S processes Consequences of environmental change in wetlands# The book provides the foundation for a basic understanding of key biogeochemical processes and its applications to solve real world problems. It is detailed, but also assists the reader with box inserts, artfully designed diagrams, and summary tables all supported by numerous current references. This book is an excellent resource for senior undergraduates and graduate students studying ecosystem biogeochemistry with a focus in wetlands and aquatic systems.

Download or read book The Structure and Function of Peatlands in the Hudson Bay Lowland written by Lorna Harris and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The peatlands of the Hudson Bay Lowland (HBL) are the world's second largest expanse of northern peatland and are globally important carbon (C) stores. Within the bogs and fens covering this extensive landscape, small-scale variations in surface elevation (microtopography - hummocks and hollows) form distinct spatial patterns accentuated by different vegetation cover related to water table depth. These spatial differences in peatland structure and biogeochemical function enable peatlands to occupy alternate dry and wet stable states, therefore increasing peatland resilience to environmental change. The objectives of this research were to examine mechanisms controlling peatland structure and function through analysis of field evidence from HBL peatlands. Relationships among vegetation, hydrology, and nutrients were examined for peatland microforms to test current hypotheses and conditions of peatland development models, and whether these models are applicable to HBL peatlands. My analysis shows the development of surface patterns of microforms within the HBL peatlands may be explained by small-scale structuring mechanisms that control peat accumulation at the microform scale, specifically, the peat accumulation and water ponding mechanisms. Vegetation type is an important control, with greater shrub cover on hummocks associated with larger production for hummocks than hollows. My results also suggest the occurrence of different spatial patterns depends on position within a peat landform, with these differences attributed to varying ecohydrological settings related to landscape-scale hydrology. In turn, the ecohydrological setting influences the strength and direction of feedback mechanisms controlling peat accumulation at the microform scale. Mat-forming lichens cover a large area of the surface of HBL peatlands (up to 50 % in places) and are an important control for peat accumulation and microform development. My results demonstrate that where there are thick lichen mats, local peat accumulation ceases through smaller productivity, faster lichen decay rates, and a loss of structural integrity in underlying peat. Lichens therefore represent a significant temporary limit to peat growth, likely constraining or reducing hummock height relative to adjacent hollows.The potential effects of hydrological change (drier conditions and lower water tables caused by gradual short-term drainage) on these relationships, and on peatland structure and function, were also assessed. My results reveal changes in vegetation and biogeochemical processes are dependent on microform. A significant loss of vegetation and associated biogeochemical changes in dry pools indicate a shift in ecosystem state. Minor changes for hummocks and intermediate microforms however, demonstrate the resilience of HBL peatlands to hydrological change that may be analogous to future climate change scenarios. This thesis contributes new knowledge on the current state of bogs and fens in the HBL for which there has been limited research, and provides insight into possible mechanisms controlling peatland structure and function. This understanding will be invaluable when considering the risks of climate change and increasing development for infrastructure and mining in these iconic peatlands. " --