Carbon Cycling In Deep Sea And Contrasting Continential Margin Sediments

Carbon dioxide and other `greenhouse' gases are increasing in the atmosphere due to the burning of fossil fuels, the destruction of rain forests, etc., leading to predictions of a gradual global warming which will perturb the global biosphere. An important process which counters this trend toward potential climate change is the removal of carbon dioxide from the surface ocean by photosynthesis. This process packages carbon in phytoplankton which enter the food chain or sink into the deep sea. Their ultimate fate is a `rain' of organic debris out of the surface-mixed layer of the ocean. On a global scale, the mechanisms and overall rate of this process are poorly known. The authors of the 25 papers in this volume present their state-of-the-art approaches to quantifying the mechanisms by which the `rain' of biogenic debris nourishes deep ocean life. Prominent deep sea ecologists, geochemists and modelers address relationships between data and models of carbon fluxes and food chains in the deep ocean. An attempt is made to estimate the fate of carbon in the deep sea on a global scale by summing up the utilization of organic matter among all the populations of the abyssal biosphere. Comparisons are made between these ecological approaches and estimates of geochemical fluxes based on sediment trapping, one-dimensional geochemical models and horizontal (physical) input from continental margins. Planning interdisciplinary enterprises between geochemists and ecologists, including new field programs, are summarized in the final chapter. The summary includes a list of the important gaps in understanding which must be addressed before the role of the deep-sea biota in global-scale processes can be put in perspective.

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.

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.

After a brief introduction to the distribution of deep-sea sediments, we show how the activities of marine organisms cycle nutrients and other dissolved constituents within the oceans, and influence the rates at which both solid and dissolved material is removed to sediments. Chapter 3 reviews the carbonate system and ends with a brief excursion into palaeoceanography. We conclude by describing the biological and chemical processes that continue long after sediments have been deposited on the deep-sea floor.

A comprehensive guide to carbon inside Earth - its quantities, movements, forms, origins, changes over time and impact on planetary processes. This title is also available as Open Access on Cambridge Core.

'Deep-Sea Sediments' focuses on the sedimentary processes operating within the various modern and ancient deep-sea environments. The chapters track the way of sedimentary particles from continental erosion or production in the marine realm, to transport into the deep sea, to final deposition on the sea floor.

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.

This book is a product of the joint JGOFS (Joint Global Ocean Flux Study)/LOICZ (Land–Ocean Interactions in the Coastal Zone) Continental Margins Task Team which was established to facilitate continental margins research in the two projects. It contains signi cant information on the physical, biogeochemical, and ecosystems of continental margins nationally and regionally and provides a very valuable synthesis of this information and the physical, biogeochemical and ecosystem processes which occur on continental margins. The publication of this book is timely as it provides a very strong foundation for the development of the joint IMBER (Integrated Marine Biogeochemistry and Ecosystems Research)/LOICZ Science Plan and Implemen- tion Strategy for biogeochemical and ecosystems research in the continental margins and the impacts of global change on these systems. This initiative will move forward integrated biogeochemical and ecosystems research in the continental margins. We thank all the contributors to this volume and especially Kon-Kee Liu who has dedicated a great deal of time to ensuring a high-quality book is published. IMBER Scienti c Steering Committee Julie Hall LOICZ Scienti c Steering Committee Jozef Pacyna v 1 Preface In general, interfaces between the Earth’s larger material reservoirs (i. e. , the land, atmosphere, ocean, and sediments) are important in the control of the biogeoche- cal dynamics and cycling of the major bio-essential elements, including carbon (C), nitrogen (N), phosphorus (P), sulfur (S), and silicon (Si), found in organic matter and the inorganic skeletons, shells, and tests of benthic and marine organisms.