Download or read book The influence of phytoplankton assemblage composition on biogeochemical characteristics and cycles in the southern Ross Sea Antarctica written by W.O. SMITH and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Microbial Response to a Rapidly Changing Marine Environment Global Warming and Ocean Acidification written by Mi Sun Yun and published by Frontiers Media SA. This book was released on 2021-09-24 with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oceanography and Marine Biology written by S. J. Hawkins and published by CRC Press. This book was released on 2018-09-03 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chapter 3 of this book is freely available as a downloadable Open Access PDF under a Creative Commons Attribution-Non Commercial-No Derivatives 3.0 license. https://s3-us-west-2.amazonaws.com/tandfbis/rt-files/docs/Open+Access+Chapters/9781138318625_oachapter3.pdf Oceanography and Marine Biology: An Annual Review remains one of the most cited sources in marine science and oceanography. The ever increasing interest in work in oceanography and marine biology and its relevance to global environmental issues, especially global climate change and its impacts, creates a demand for authoritative reviews summarizing the results of recent research. OMBAR has catered to this demand since its foundation more than 50 years ago. Following the favourable reception and complimentary reviews accorded to all the volumes, Volume 56 continues to regard the marine sciences—with all their various aspects—as a unity. Physical, chemical, and biological aspects of marine science are dealt with by experts actively engaged in these fields, and every chapter is peer-reviewed by other experts working actively in the specific areas of interest. The series is an essential reference text for researchers and students in all fields of marine science and related subjects, and it finds a place in libraries of universities, marine laboratories, research institutes and government departments.
Download or read book Polynyas Windows to the World written by Walker O. Smith Jr. and published by Elsevier. This book was released on 2007-07-09 with total page 475 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approx.474 pages Approx.474 pages
Download or read book Photosynthesis irradiance relationships in the Ross Sea Antarctica and their control by phytoplankton assemblage composition and environmental factors written by C.M. van HILST and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book US Southern Ocean JGOFS Program AESOPS written by Robert Frederick Anderson and published by . This book was released on 2000 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The U S JGOFS Synthesis and Modeling Project written by and published by . This book was released on 2006 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Exploring Light Controls on Phytoplankton Community Structure and the Biogeochemistry of the Ross Sea Antarctica written by Lindsey Rae Kropuenske and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Southern Ocean is one of the most important regions on Earth for absorption of anthropogenic carbon dioxide (CO2) from the atmosphere and long-term storage of that carbon in deep water and ocean sediments. While a significant amount of CO2 enters the deep ocean in this region along oceanographic fronts through the solubility pump, large seasonal phytoplankton blooms form on the Antarctic continental shelf and suggest that the biological pump also plays an important, and possibly underestimated, role in the oceanic sequestration of atmospheric CO2. This dissertation investigates the mechanisms by which light may control phytoplankton species distributions in one of the most productive areas of the Antarctic continental shelf, the Ross Sea. The Ross Sea is commonly dominated by two major phytoplankton species, diatoms, and the haptophyte, Phaeocystis antarctica. The distributions of these species are often correlated with different mixed layer environments, with diatoms dominating shallow mixed layers and P. antarctica dominating deeper mixed layers. Using a series of laboratory experiments, differences were assessed between P. antarctica and the common Ross Sea diatom, Fragilariopsis cylindrus, in their capacity for xanthophyll cycle photoprotection (Chapter 2). This was followed by chemical inhibition experiments that quantified the relative important of xanthophyll cycle photoprotection and the repair of photodamage for maintaining photosynthetic performance in each species. F. cylindrus produced significantly higher concentrations of xanthophyll cycle pigment and epoxidation of activated pigment (diatoxanthin epoxidation to diadinoxanthin) occurred much more slowly upon transition to low light than in P. antarctica. Although both species relied on xanthophyll cycle photoprotection to avoid photoinhibition and maintain maximal photosynthetic rates, P. antarctica was much more adversely affected when repair of photodamage was inhibited. Differences between species in strategies and rates of photoacclimation were also assessed (Chapter 3). F. cylindrus acclimated to shifts in irradiance by adjusting photosynthetic efficiency, with large changes in the functional absorption cross-section of photosystem two ([sigma]PSII) inferred from physiological measurements. P. antarctica exhibited significant changes in both photosynthetic efficiency and the maximum capacity for photosynthesis following shifts in irradiance. Changes in both [sigma]PSII and the number photosynthetic reaction centers or their maximum turnover rate were inferred from physiological measurements. Light was also found to play an important role in controlling elemental ratios in F. cylindrus and P. antarctica (Chapter 4). Particulate organic carbon to nitrogen to phosphorus ratios (C:N:P) varied as a function of growth irradiance in both species, but significant differences between species grown in identical conditions were also observed. F. cylindrus exhibited C:N:P ratios that were significantly lower than those of P. antarctica and often below the Redfield ratio, in agreement with observations from the Ross Sea. In contrast, P. antarctica exhibited ratios above the Redfield ratio when grown in all but very high light conditions. While protein, nucleic acid, and chlorophyll (Chl) concentrations explained the provenance of nearly 100% of particulate N in both species, nucleic acid concentrations were not sufficient to explain particulate P in either species. The remaining P could be partially accounted for if these species produce large concentrations of phospholipids, but storage of inorganic P most likely forms the largest cellular P-pool in nutrient replete cultures. Finally, data from the laboratory experiments were used to calculate phytoplankton growth rates in an ecosystem model of the Ross Sea to test the hypothesis that photophysiological differences between diatoms and P. antarctica can explain their distributions (Chapter 5). The phytoplankton growth model was modified from a previous steady-state model that included four physiological variables, the maximum quantum yield of photosynthesis ([phi]M), the irradiance at which [phi] = 1/2 [phi]M, the carbon to Chl ratio, and mean Chl-specific absorption. The parameters were allowed to vary as a function of mean mixed layer irradiance according to equations derived from laboratory data and acclimation rates measured in light shift experiments. Chl concentrations and distributions of P. antarctica and diatoms in the model agreed well with field observations, demonstrating that light is sufficient to explain phytoplankton community composition in the Ross Sea. These results also demonstrate that physiological information collected from ecologically relevant algal cultures can be used to understand and model phytoplankton dynamics in the natural environment.
Download or read book Upper Ocean Physical and Ecological Dynamics in the Ross Sea Antarctica written by Matthew Charles Long and published by Stanford University. This book was released on 2010 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation examines several aspects of the unique physical-biological system that controls biogeochemical cycling in the Ross Sea, the largest continental shelf sea along the Antarctic margin and the most biologically productive region in the Southern Ocean. The core component of the research involves interpretation of data from two oceanographic cruises to the region, one during Summer of 2005--2006 and another in Spring of 2006--2007. Four key research questions are addressed. (1) What physical mechanisms force spatial and temporal variability in mixing depths? (2) How does the dynamic physical environment characteristic of Antarctic continental shelf seas structure distributions of biomass and chemical tracers of production? (3) What key physical and physiological mechanisms control the 13C/12C ratio of organic and inorganic carbon in waters on the Ross Sea continental shelf? and (4) How do physiological variables interact with environmental variability to control phytoplankton taxonomic zonation? Chapter 1 presents an introduction to ocean carbon biogeochemistry and the oceanography of the Southern Ocean and the Ross Sea. Chapter 2 examines the mechanisms effecting early season stratification in the Ross Sea. Lateral advection in the region of upper ocean fronts is shown to be an important mechanism setting early season stratification. Chapter 3 examines several tracer-based methods for estimating upper ocean net community production in the Ross Sea, with explicit recognition of the complexities associated with control volume assumptions and high rates of temporal change. Chapter 4 considers the environmental controls on the distribution of 13C/12C ratios in the Ross Sea. It is shown quantitatively that the two dominant phytoplankton taxa in the Ross Sea have different intrinsic fractionation factors, likely as a result of differing carbon-acquisition physiologies. Air-sea exchange is shown to occur with very noisy fractionation. Finally, Chapter 5 examines the interaction of algal physiology with environmental variability, addressing the key physiological-environmental controls on the taxonomic distribution of phytoplankton in the Ross Sea. While it is difficult to draw concrete conclusions, the most compelling line of evidence suggests that differing photoprotective capacities is the most important physiological characteristic structuring taxonomic distributions. An appendix presents a design for an infrared absorbance-based instrument for the determination of total dissolved inorganic carbon in seawater.
Download or read book Mycosporine like Amino Acids MAAs in Bloom forming Phytoplankton written by Elizabeth Rose Frame and published by . This book was released on 2004 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings written by and published by . This book was released on 2009 with total page 630 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Crozet Natural Iron Bloom and Export Experiment written by and published by . This book was released on 2007 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling the Plankton Enhancing the Integration of Biological Knowledge and Mechanistic Understanding written by Christian Lindemann and published by Frontiers Media SA. This book was released on 2017-12-28 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: In light of climate change and allied changes to marine ecosystems, mathematical models have become an important tool to examine processes and predict phenomena from local through to global scales. In recent years model studies, laboratory experiments and a better ecological understanding of the pelagic ecosystem have enabled advancements on fundamental challenges in oceanography, including marine production, biodiversity and anticipation of future conditions in the ocean. This research topic presents a number of studies that investigate functionally diverse organism in a dynamic ocean through diverse and novel modeling approaches.
Download or read book Regulation and Impact of the Phytoplankton Assemblage Composition in the Southern Ocean written by Jill A. Peloquin and published by . This book was released on 2005 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Using High resolution Glider Data and Biogeochemical Modeling to Investigate Phytoplankton Variability in the Ross Sea written by Daniel Edward Kaufman and published by . This book was released on 2017 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: As Earth’s climate changes, polar environments experience a disproportionate share of extreme shifts. Because the Ross Sea shelf has the highest annual productivity of any Antarctic continental shelf, this region is of particular interest when striving to characterize current and future changes in Antarctic systems. However, understanding of mesoscale variability of biogeochemical patterns in the Ross Sea and how this variability affects assemblage dynamics is incomplete. Furthermore, it is unknown how the Ross Sea may respond to projected warming, reduced summer sea ice concentrations, and shallower mixed layers during the next century. To investigate these dynamics and explore their consequences over the next century, high-resolution glider observations were analyzed and used in conjunction with a one-dimensional, data-assimilative biogeochemical-modeling framework. An analysis of glider observations from two latitudinal sections in the Ross Sea characterized mesoscale variability associated with the phytoplankton bloom and highlighted potential mechanisms driving change in the assemblage. In particular, an observed increase in the ratio of carbon to chlorophyll (C:Chl) suggested a marked transition from a phytoplankton assemblage dominated by Phaeocystis antarctica- to one dominated by diatoms. The expected control of phytoplankton variability by Modified Circumpolar Deep Water and mixed layer depth were shown to be insignificant relative to the effects of wind and sea surface temperature on the temporal/spatial scales measured by the glider. Additional glider measurements were used to force the Model of Ecosystem Dynamics, nutrient Utilisation, Sequestration and Acidification, which was adapted for use in the Ross Sea (MEDUSA-RS) to include both solitary and colonial forms of Phaeocystis antarctica. The impacts of climate-induced changes on Ross Sea phytoplankton were investigated with MEDUSA-RS using projections of physical drivers for mid- and late-21st century, and these experiments indicated increases of primary productivity and carbon export flux. Additional scenario experiments demonstrated that earlier availability of low light due to reduction of sea ice early in the growing season was the primary driver of simulated productivity increases over the next century; shallower mixed layer depths additionally contributed to changes of phytoplankton composition and export. Glider data were assimilated into MEDUSA-RS using the Marine Model Optimization Testbed (MarMOT) to optimize eight phytoplankton model parameters. Assimilation experiments that used different data subsets suggest that assimilating observations at the surface alone, as are typically available from remote-sensing platforms, may underestimate carbon export to depth and overestimate primary production. Experiments assimilating observations characteristic of a cruise-based sampling frequency produced a wide range of solutions, depending on which days were sampled, suggesting the potential for large errors in productivity and export. Finally, assimilating data from different spatial areas resulted in less variation of optimal solutions than assimilating data from different time periods in the bloom progression; these temporal differences are primarily driven by decreasing colonial P. antarctica growth rates, increasing colonial P. antarctica C:Chl, and faster sinking of colonies as the bloom progresses from the accumulation stage through dissipation. Overall, this dissertation research demonstrates the value of using bio-optical glider observations in conjunction with modeling to characterize phytoplankton dynamics in a remote marine ecosystem. High-resolution glider data are better able to resolve mesoscale physical-biological relationships, which are typically not discernible from lower frequency data, but it can be difficult to identify mechanistic relationships from in situ measurements alone. In addition, biogeochemical models can be used to extend insights gained by empirical observation, but application is often limited by the quantity and type of in situ data appropriate for evaluation and forcing. The use of gliders for facilitating development and operation of a lower trophic level model demonstrated the effectiveness of a synthetic approach that partly overcomes the individual limitations of these otherwise distinct approaches. Finally, the combination of these approaches is especially useful for gaining a better understanding of ecosystem dynamics in regions similar to the Ross Sea that are undergoing substantive climate-induced changes and where harsh conditions make other means of access difficult.
Download or read book Ocean Environment and Fisheries written by M P M Reddy and published by CRC Press. This book was released on 2007-01-09 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aspects relating to climatic conditions, continental shelf, currents, upwelling, distribution of sea water temperature, salinity, dissolved oxygen, phosphate, nitrate, silicate, phytoplankton, zooplankton and benthos and also maximum and minimum annual mean values of various oceanographic factors at different depths and yearly average catches of major fish categories are given in Chapter 5 for the Atlantic Ocean; in Chapter 6 for the Pacific Ocean; in Chapter 7 for the Indian Ocean and in Chapter 8 for the Southern Ocean. Chapter 9 gives a brief account of some of the recent studies carried out on the influence of oceanographic factors on fisheries in the Atlantic, Pacific and Indian Oceans. Chapter 10 presents forecasts." "This book is intended for those engaged in research and teaching of physical oceanography, chemical oceanography, biological oceanography, fisheries and fishery oceanography."--BOOK JACKET.
Download or read book Carbon and Nutrient Fluxes in Continental Margins written by Kon-Kee Liu and published by Springer Science & Business Media. This book was released on 2010-02-11 with total page 757 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
