Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Benthic Carbon Demand And Community Structure Across The Pacific Arctic Continental Shelves
Download Benthic Carbon Demand And Community Structure Across The Pacific Arctic Continental Shelves full books in PDF, epub, and Kindle. Read online Benthic Carbon Demand And Community Structure Across The Pacific Arctic Continental Shelves ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Benthic Carbon Demand and Community Structure Across the Pacific Arctic Continental Shelves by : Brittany Robinson Charrier
Download or read book Benthic Carbon Demand and Community Structure Across the Pacific Arctic Continental Shelves written by Brittany Robinson Charrier and published by . This book was released on 2022 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: High latitude continental shelves are experiencing rapid environmental change. The Pacific Arctic, which includes the northern Bering and southern Chukchi Sea continental shelves, is undergoing warming temperatures, reductions in sea ice, and changes to the marine ecosystem. Fieldwork was conducted across the northern Bering and southern Chukchi Sea continental shelves in June 2017 and June 2018 on the R/V Sikuliaq. The overall objective of this dissertation was to characterize benthic community structure, function, and carbon demand in the Pacific Arctic to serve as baselines for assessing impacts of environmental change. Spatial patterns of macrofauna and meiofauna were characterized, including abundances, biomass, composition, and vertical distribution within the sediment. Polychaete structure and function were assessed in detail by identifying polychaetes to family level and assigning each a functional guild based on feeding mode, motility, and feeding structures. Nematodes were identified to genus level and characterized by feeding type and life-history strategy. Clusters of polychaete functional guilds and nematode genera assemblages were similar and occupied different general regions within the Pacific Arctic: northern Bering Sea, Bering Strait, offshore Chukchi Sea, and coastal Chukchi Sea. These polychaete and nematode assemblages were associated with different depositional and food environments, characterized by grain size and the amount and quality of sediment organic matter. In addition, metabolic and carbon demand of dominant macrofaunal were estimated based on oxygen consumption rates. Species-specific rates suggest that shifts in macrofaunal community composition in the region will impact benthic carbon demand. Overall, the research presented here provides critical baseline data for benthic community structure, function, and carbon demand in the Pacific Arctic and can be used to evaluate change and constrain region-specific ecosystem models, especially in the context of a rapidly changing environment.
Book Synopsis The Pacific Arctic Region by : Jacqueline M. Grebmeier
Download or read book The Pacific Arctic Region written by Jacqueline M. Grebmeier and published by Springer. This book was released on 2014-06-10 with total page 461 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pacific Arctic region is experiencing rapid sea ice retreat, seawater warming, ocean acidification and biological response. Physical and biogeochemical modeling indicates the potential for step-function changes to the overall marine ecosystem. This synthesis book was coordinated within the Pacific Arctic Group, a network of international partners working in the Pacific Arctic. Chapter topics range from atmospheric and physical sciences to chemical processing and biological response to changing environmental conditions. Physical and biogeochemical modeling results highlight the need for data collection and interdisciplinary modeling activities to track and forecast the changing ecosystem of the Pacific Arctic with climate change.
Book Synopsis Benthic Carbon Cycling on the Antarctic Continental Shelf by : Marwa Baloza
Download or read book Benthic Carbon Cycling on the Antarctic Continental Shelf written by Marwa Baloza and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The sedimentation of pelagic production makes continental shelf sediments important sites for organic matter (OM) remineralization and nutrient regeneration in the ocean. Consequently, shelf sediments play an important role in the bentho-pelagic coupling by providing essential nutrients for algal growth and maintaining the high primary production of shelf areas and the adjacent open ocean. In Antarctica, changes in sea ice cover have a major impact on surface primary production and the subsequent sinking of organic carbon to the seafloor. Recent observations indicate that global warming has led to substantial changes in sea ice cover, with a significant reduction of one million square kilometers in the annual maximum sea ice extent around Antarctica. These changes in sea ice conditions are expected to trigger significant changes in the pelagic ecosystem, with potentially profound effects on the benthic ecosystem. The imprint of climate-sensitive variables such as sea ice cover can be best studied in shelf sediments, where shallow water depths result in increased OM supply and tighter bentho-pelagic coupling. Therefore, a comprehensive understanding of the current carbon cycle on the Antarctic continental shelf is crucial for assessing the vulnerability of the ecosystem to climate change and for predicting the future trajectory of the carbon cycle in Antarctic waters. This thesis aims to quantify benthic carbon remineralization rates on the Antarctic continental shelf and the release of nutrients, particularly iron, that limit primary production in the Southern Ocean. In addition, the thesis aims to identify the main pathways of OM degradation and associated microbial communities, while contextualizing the above variables within the prevailing sea ice conditions. For this purpose, I first studied the geochemistry of shelf sediments along a gradient of sea ice cover on the eastern shelf of the Antarctic Peninsula (AP) (manuscript 1). The main focus was on carbon and iron fluxes within the sediment and between the water column and the sediment. The results were interpreted in the context of sea ice cover. An increase in carbon remineralization rates was observed as one moved from heavily ice-covered to moderately ice-covered stations where light availability and water column stratification increased. Conversely, the ice-free station displayed lower carbon remineralization rates and was subject to wind-driven mixing of the water column, which can deepen the mixed layer depth below the critical depth, resulting in reduced surface production. In summary, a positive correlation was found between moderate sea ice cover and increased carbon fluxes to the sediment, which followed an exponential increase. The study also revealed significant iron cycling in sediments with increased carbon remineralization, resulting in high dissolved iron fluxes. This finding highlights the importance of sediments underlying the moderate ice cover as a source of limiting nutrients for primary production in this region. A complementary study of benthic microbial communities along the AP transect was conducted using 16S ribosomal RNA (rRNA) gene sequencing (manuscript 2). The results indicate that sea ice cover and its effect on organic carbon fluxes are the main drivers of changes in benthic microbial communities. As sea ice cover decreases, the benthic microbial community shifts towards anaerobic communities of iron and sulfate reducers. These communities were more abundant at low ice cover stations than at high ice cover stations. Furthermore, an increase in the relative abundance of Sva1033, a Desulfuromonadia clade, with dissolved iron concentration at low ice cover stations suggests a putative role for Sva1033 in dissimilatory iron reduction in surface sediments. In addition to Sva1033, this study successfully identified other taxa that could potentially contribute to dissimilatory iron reduction or have syntrophic partnerships and/or common metabolic preferences with iron reducers. The focus was extended towards the southern shelf of the Weddell Sea, a region characterized by heavy sea ice cover (manuscript 3). Benthic oxygen uptake rates were measured at stations with different water depths and sediment compositions. Benthic measurements also revealed a dependence of carbon fluxes on sediment grain size and water depth. In general, diffusive oxygen uptake (DOU) rates on the southern Weddell Sea shelf were low. DOU showed a positive correlation with preserved total organic carbon (TOC) at stations with fine-grained sediments, whereas stations with typical of coarse-grained sediments showed a markedly different correlation of DOU with TOC. Common to all stations is that dissolved iron and manganese concentrations in pore water were found only at greater depths, suggesting very limited release of these nutrients back into the water column. The strong dependence of benthic carbon fluxes on sea ice cover and water depth was then combined to derive a simple empirical model, which was validated by all available DOU measurements reported in the literature for the Antarctic seasonal ice zone (manuscript 4). The model allows extrapolation and budgeting of benthic carbon remineralization for the entire seasonal ice zone (16 million km2), yielding a total of 46 Tg C yr-1. Notably, although the Antarctic continental shelf represents only 15% of the total area, it contributes a significant 71% (33 Tg C yr-1) of the total benthic carbon remineralization. Furthermore, the total organic carbon supply to the sediments and the carbon burial in the sediments were estimated to amount to 52 Tg C yr-1 and 6 Tg C yr-1, respectively. Overall, the thesis highlights the pivotal role of sea ice cover in controlling the benthic carbon and iron cycling on the Antarctic continental shelf. Through extensive data correlation and empirical modeling, the thesis has provided, for the first time, a quantitative framework for the relationship between sea ice cover and benthic carbon fluxes. It also emphasizes the substantial contribution of Antarctic shelf sediments to the marine carbon remineralization, allowing a better assessment of the carbon cycling and related CO2 sequestration across the Southern Ocean. Furthermore, it has improved our understanding of the main drivers of change in benthic microbial communities and, ultimately, nutrient fluxes across the sediment-water interface. These findings make a significant contribution to our understanding of the complex Antarctic ecosystem, which is necessary to assess the future trajectory of the Southern Ocean and its impact on the global carbon cycle.
Book Synopsis The Evolutionary Biology of the Bivalvia by : Elizabeth Harper
Download or read book The Evolutionary Biology of the Bivalvia written by Elizabeth Harper and published by Geological Society of London. This book was released on 2000 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bivalves are key components of recent marine and freshwater ecosystems and have been so for most of the Phanerozoic. Their rich and long fossil record, combined with their abundance and diversity in modern seas, has made bivalves the ideal subject of palaeobiological and evolutionary studies. Despite this, however, topics such as the early evolution of the class, relationships between various taxa and the life habits of some key extinct forms have remained remarkably unclear. This volume integrates palaeontological and zoological approaches and sheds new light on the course of bivalve evolution.
Author :Intergovernmental Panel on Climate Change (IPCC) Publisher :Cambridge University Press ISBN 13 :9781009157971 Total Pages :755 pages Book Rating :4.1/5 (579 download)
Book Synopsis The Ocean and Cryosphere in a Changing Climate by : Intergovernmental Panel on Climate Change (IPCC)
Download or read book The Ocean and Cryosphere in a Changing Climate written by Intergovernmental Panel on Climate Change (IPCC) and published by Cambridge University Press. This book was released on 2022-04-30 with total page 755 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for assessing the science related to climate change. It provides policymakers with regular assessments of the scientific basis of human-induced climate change, its impacts and future risks, and options for adaptation and mitigation. This IPCC Special Report on the Ocean and Cryosphere in a Changing Climate is the most comprehensive and up-to-date assessment of the observed and projected changes to the ocean and cryosphere and their associated impacts and risks, with a focus on resilience, risk management response options, and adaptation measures, considering both their potential and limitations. It brings together knowledge on physical and biogeochemical changes, the interplay with ecosystem changes, and the implications for human communities. It serves policymakers, decision makers, stakeholders, and all interested parties with unbiased, up-to-date, policy-relevant information. This title is also available as Open Access on Cambridge Core.
Book Synopsis The Organic Carbon Cycle in the Arctic Ocean by : Rüdiger Stein
Download or read book The Organic Carbon Cycle in the Arctic Ocean written by Rüdiger Stein and published by Springer Science & Business Media. This book was released on 2011-06-27 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flux, preservation, and accumulation of organic carbon in marine systems are controlled by various mechanisms including primary p- duction of the surface water, supply of terrigenous organic matter from the surrounding continents, biogeochemical processes in the water column and at the seafloor, and sedimentation rate. For the world's oceans, phytoplankton productivity is by far the largest organic carbon 9 source, estimated to be about 30 to 50 Gt (10 tonnes) per year (Berger et al. 1989; Hedges and Keil 1995). By comparison, rivers contribute -1 about 0. 15 to 0. 23 Gt y of particulate organi.
Book Synopsis Methods for the Study of Marine Benthos by : Anastasios Eleftheriou
Download or read book Methods for the Study of Marine Benthos written by Anastasios Eleftheriou and published by John Wiley & Sons. This book was released on 2008-04-15 with total page 443 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ecosystems of the benthic environment are a sensitive index toecological change, and as such demand long-term and effectivemonitoring. Methods for the Study of Marine Benthos providescomprehensive information on the tools and techniques available tothose working in areas where the declining health of the sea,depletion of marine resources and the biodiversity of marine lifeare major concerns. In response to the need for increasingly detailed information onbottom-living communities, this fully revised new editionoffers: Contributions from a broad range of internationally recognisedexperts New information for those compiling environmental impactstatements, pollution assessments and working with eco-systemmanagement Two separate chapters on Imaging Techniques and DivingSystems A vital tool for all marine and environmental scientists,ecologists, fisheries workers and oceanographers, libraries in alluniversities and research establishments where these subjects arestudied and taught will find this book a valuable addition to theirshelves.
Book Synopsis Advances in the Studies of the Benthic Zone by : Luis Soto
Download or read book Advances in the Studies of the Benthic Zone written by Luis Soto and published by BoD – Books on Demand. This book was released on 2020-06-10 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an unpretentious editing venture to fill the gap in our current knowledge on the ecological implications caused by anthropogenic disturbances upon benthic communities in several regions of the world, including the Western Atlantic, the Mediterranean Sea, and the Eastern Pacific Ocean, as well as the pristine environments of the Andes in South America. The common goal of the contributing authors in this book was to unravel the complex processes that make possible the life existence of bottom-living animals in different environmental scenarios. To achieve such a goal, the authors focus their attention on the emerging issues inherent to global climate change or the pollution of aquatic systems. These are all themes that might be of interest to scientists active in a wide range of oceanographic subdisciplines. Well-established researchers would appreciate the innovative approach adopted in each chapter of the book, which extends from the ecosystem level to refined molecular interpretations.
Book Synopsis Marine Carbon Biogeochemistry by : Jack J. Middelburg
Download or read book Marine Carbon Biogeochemistry written by Jack J. Middelburg and published by Springer. This book was released on 2019-01-25 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book discusses biogeochemical processes relevant to carbon and aims to provide readers, graduate students and researchers, with insight into the functioning of marine ecosystems. A carbon centric approach has been adopted, but other elements are included where relevant or needed. The book focuses on concepts and quantitative understanding of primary production, organic matter mineralization and sediment biogeochemistry. The impact of biogeochemical processes on inorganic carbon dynamics and organic matter transformation are also discussed.
Book Synopsis Extreme Benthic Communities in the Age of Global Change by : Roberto Sandulli
Download or read book Extreme Benthic Communities in the Age of Global Change written by Roberto Sandulli and published by Frontiers Media SA. This book was released on 2021-02-11 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Ocean Biogeochemistry by : Michael J.R. Fasham
Download or read book Ocean Biogeochemistry written by Michael J.R. Fasham and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oceans account for 50% of the anthropogenic CO2 released into the atmosphere. During the past 15 years an international programme, the Joint Global Ocean Flux Study (JGOFS), has been studying the ocean carbon cycle to quantify and model the biological and physical processes whereby CO2 is pumped from the ocean's surface to the depths of the ocean, where it can remain for hundreds of years. This project is one of the largest multi-disciplinary studies of the oceans ever carried out and this book synthesises the results. It covers all aspects of the topic ranging from air-sea exchange with CO2, the role of physical mixing, the uptake of CO2 by marine algae, the fluxes of carbon and nitrogen through the marine food chain to the subsequent export of carbon to the depths of the ocean. Special emphasis is laid on predicting future climatic change.
Book Synopsis Deep-sea Biodiversity by : Michael A. Rex
Download or read book Deep-sea Biodiversity written by Michael A. Rex and published by Harvard University Press. This book was released on 2010 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rex and Etter present the first synthesis of patterns and causes of biodiversity in organisms that dwell in the vast sediment ecosystem of ocean floor. They offer a new understanding of marine biodiversity that will be of general interest to ecologists and is crucial to responsible exploitation of natural resources at the deep-sea floor.
Book Synopsis Ecosystems of the Deep Oceans by : P.A. Tyler
Download or read book Ecosystems of the Deep Oceans written by P.A. Tyler and published by Elsevier. This book was released on 2003-03-27 with total page 581 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume examines the deep sea ecosystem from a variety of perspectives. The initial chapters examine the deep-sea floor, the deep pelagic environment and the more specialised chemosynthetic environments of hydrothermal vents and cold seeps. These environments are examined from the perspective of the relationship of deep-sea animals to their physico-chemical environment. Later chapters examine the biogeography of the main deep oceans (Atlantic, Pacific and Indian) with particular attention to the downward flux of surface-derived organic matter and how this drives the processes within the deep-sea ecosystem. The peripheral deep seas including the polar seas and the marginal deep seas (inter alia the Mediterranean, Red, Caribbean and Okhotsk seas) are explored in the same context. The final chapters examine the processes occurring in the deep sea and include an analysis of why the deep sea has high species diversity, how the fauna respond to organic input and how species have adapted reproductive activity in the deep sea. The volume concludes with an analysis of the anthropogenic impact on the deep sea.
Book Synopsis Ecology and Palaeoecology of Benthic Foraminifera by : John W. Murray
Download or read book Ecology and Palaeoecology of Benthic Foraminifera written by John W. Murray and published by Routledge. This book was released on 2014-10-13 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an important and authoritative review of foraminiferal ecology, the first for over a decade. Professor Murray relates ecological data on living forms of foraminifera to the palaeoecology of fossil species, and defines in detail areas of global distribution.
Download or read book Arctic Ecology written by David N. Thomas and published by John Wiley & Sons. This book was released on 2021-01-26 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Arctic is often portrayed as being isolated, but the reality is that the connectivity with the rest of the planet is huge, be it through weather patterns, global ocean circulation, and large-scale migration patterns to name but a few. There is a huge amount of public interest in the ‘changing Arctic’, especially in terms of the rapid changes taking place in ecosystems and exploitation of resources. There can be no doubt that the Arctic is at the forefront of the international environmental science agenda, both from a scientific aspect, and also from a policy/environmental management perspective. This book aims to stimulate a wide audience to think about the Arctic by highlighting the remarkable breadth of what it means to study its ecology. Arctic Ecology seeks to systematically introduce the diverse array of ecologies within the Arctic region. As the Arctic rapidly changes, understanding the fundamental ecology underpinning the Arctic is paramount to understanding the consequences of what such change will inevitably bring about. Arctic Ecology is designed to provide graduate students of environmental science, ecology and climate change with a source where Arctic ecology is addressed specifically, with issues due to climate change clearly discussed. It will also be of use to policy-makers, researchers and international agencies who are focusing on ecological issues and effects of global climate change in the Arctic. About the Editor David N. Thomas is Professor of Arctic Ecosystem Research in the Faculty of Biological and Environmental Sciences, University of Helsinki. Previously he spent 24 years in the School of Ocean Sciences, Bangor University, Wales. He studies marine systems, with a particular emphasis on sea ice and land-coast interactions in the Arctic and Southern Oceans as well as the Baltic Sea. He also edited a related book: Sea Ice, 3rd Edition (2017), which is also published by Wiley-Blackwell.
Book Synopsis Ecological Geography of the Sea by : Alan R. Longhurst
Download or read book Ecological Geography of the Sea written by Alan R. Longhurst and published by Elsevier. This book was released on 2010-08-03 with total page 575 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an in-depth discussion of the biological and ecological geography of the oceans. It synthesizes locally restricted studies of the ocean to generate a global geography of the vast marine world.Based on patterns of algal ecology, the book divides the ocean into four primary compartments, which are then subdivided into secondary compartments. *Includes color insert of the latest in satellite imagery showing the world's oceans, their similarities and differences*Revised and updated to reflect the latest in oceanographic research*Ideal for anyone interested in understanding ocean ecology -- accessible and informative
Book Synopsis Spatial and Temporal Variations in Benthic Bivalve Stable Isotopic Composition in the Chukchi Sea, Arctic Ocean by : Hoang Minh Nguyen
Download or read book Spatial and Temporal Variations in Benthic Bivalve Stable Isotopic Composition in the Chukchi Sea, Arctic Ocean written by Hoang Minh Nguyen and published by . This book was released on 2017 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Chukchi Sea is one of the most productive marine ecosystems in the world. Around 10% of its net primary production originates from sea ice algae, much of which falls ungrazed to a relatively shallow (40 - 50 m) shelf. The chlorophyll [alpha] derived from sinking ice algae is thought to support a robust macrobenthic faunal community, dominated by bivalves, which in turn supports higher trophic organisms such as Pacific walrus (Odibenus rosmarus divergens), and bearded seal (Erignathus barbatus). However, reductions in sea ice extent and earlier break-up could reduce epontic ice algal production and enhance the contribution by phytoplankton, decreasing the relative proportion of ice algal carbon delivery to benthic consumers. To address this question, we examined the stable isotope composition of ten common benthic bivalve taxa, collected in summer and spring between 2002 and 2016, to determine if their spatial and temporal variability revealed changes in diet with respect to sea ice conditions and to identify any differences among feeding guilds. The results showed no interannual variations but revealed a significant northeast to southwest increase in [delta] 13C values. Benthic bivalves across feeding guilds also appear to assimilate a greater proportion of isotopically heavier carbon in locations with earlier ice break-up. The findings indicate high level of diet fidelity among the selected taxa and suggest there exists a 'food bank' in the Chukchi Sea sediments that is highly enriched in 13C. This sedimentary food bank could serve as a buffer to protect benthic bivalve community from changes in the delivery of ice algal carbon in response to shifting ice conditions. However, long-term changes in the delivery of reduced ice algal carbon to the seabed could result in changes in benthic community structure and production that could eventually cascade to higher trophic levels.
