Download or read book Phytoplankton Dynamics Studying Using Observation and Bio physical Modeling written by Yi Xu and published by . This book was released on 2013 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt: Continental shelf phytoplankton bloom dynamics are associated with meteorological, oceanographic and coastal forcing mechanisms. Mixing related to stratification and de-stratification is a key process of the physical environment that can control the timing and magnitude of blooms. Using data from satellite, coastal ocean observatory and bio-physical model, this study investigated the seasonal and decadal variability of chlorophyll in the Mid-Atlantic Bight and how different forcing mechanisms affect the phytoplankton bloom. The temporal and spatial distribution of chlorophyll a in the MAB was quantified using satellite data collected by the Sea-viewing Wide Field of view Sensor (SeaWiFS). The MAB undergoes a fall-winter bloom in the middle-outer shelf region and spring bloom in the shelf-break region. The interannual variability of bloom magnitude is associated with wind-induced mixing. Mixing has been recognized as having an important role in influencing underwater light and nutrient budgets and thus regulating phytoplankton bloom. The ratio of light over mixed layer depth (MLD) was used to determine the trade-off effects of mixing on phytoplankton bloom activity. We find that a critical light value around 60 (W m-2) for the shelf region and 150 (W m-2) for the shelf-break front region in promoting maximum phytoplankton biomass and there is a predictable linear regression relationship between the critical light value and depth. The bio-physical model identified the wind-induced mixing, net heat flux and river run-off are the most important factors influencing water column stability. Sensitivity studies showed that the timing of the destratification and initiation of fall bloom was closely related to the wind forcing. The river's role in bringing buoyancy was significant in increasing phytoplankton bloom. The decadal declines in the seasonal satellite estimates of chlorophyll a concentrations have been observed in the fall and winter in the MAB and are hypothesized to reflect shifts in the Atlantic Multidecadal Oscillation (AMO) that alters wind stress, river discharge, and net heat flux. This work prototypes the integration of observation and modeling in a coastal environment and demonstrates the use of 3D coupled physical-biological model forced with realistic atmospheric forcing to study the phytoplankton dynamics in the MAB.
Download or read book Unraveling Mechanisms Underlying Annual Plankton Blooms in the North Atlantic and Their Implications for Biogenic Aerosol Properties and Cloud Formation written by Kristina Dee Anne Mojica and published by Frontiers Media SA. This book was released on 2021-11-23 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamics of Planktonic Primary Productivity in the Indian Ocean written by Sarat Chandra Tripathy and published by Springer Nature. This book was released on 2023-09-12 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume compiles recent research on phytoplankton primary productivity (PP) in the Indian Ocean to provide an understanding and consolidation of the driving mechanisms of PP variability in diverse oceanic ecosystems globally. The book aims to facilitate a holistic overview of the research carried out in this field in various oceanic realms such as Indian coastal and oceanic waters (estuaries, coastal waters, Bay of Bengal, Arabian Sea, Indian Ocean). The contents of this book also address the United Nations sustainable development goals i.e., SDG 13 (Climate Action) and SDG 14 (Life below Water), with a focus on the impacts of climate change oceanic ecosystems. The book can serve as a comprehensive baseline of information for researchers studying planktonic primary productivity and biogeochemistry-related research in the above-mentioned marine ecosystems and other global oceans. It is intended to attract the attention of researchers, professionals, undergraduate and graduate oceanography students, and policy makers in the field of marine sciences.
Download or read book SeaWiFS Technical Report Series written by and published by . This book was released on 1996 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biogeochemical ecological and biophysical dynamics in the kuroshio oyashio and their extension regions written by Guangchao Zhuang and published by Frontiers Media SA. This book was released on 2023-08-23 with total page 243 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book SeaWiFS Technical Report Series written by Robert A. Barnes and published by . This book was released on 1995 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hybrid Solutions for the Modelling of Complex Environmental Systems written by Christian E. Vincenot and published by Frontiers Media SA. This book was released on 2017-01-11 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: Systems studied in environmental science, due to their structure and the heterogeneity of the entities composing them, often exhibit complex dynamics that can only be captured by hybrid modeling approaches. While several concurrent definitions of “hybrid modeling” can be found in the literature, it is defined here broadly as the approach consisting in coupling existing modelling paradigms to achieve a more accurate or efficient representation of systems. The need for hybrid models generally arises from the necessity to overcome the limitation of a single modeling technique in terms of structural flexibility, capabilities, or computational efficiency. This book brings together experts in the field of hybrid modelling to demonstrate how this approach can address the challenge of representing the complexity of natural systems. Chapters cover applied examples as well as modeling methodology.
Download or read book Physical Influences on Phytoplankton Ecology written by Sophie A. Clayton and published by . This book was released on 2013 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: The physical environment in the oceans dictates not only how phytoplankton cells are dispersed and their populations intermingled, but also mediates the supply of nutrients to the surface mixed layer. In this thesis I explore both of these aspects of the interaction between phytoplankton ecology and ocean physics, and have approached this topic in two distinct but complementary ways, working with a global ocean ecosystem model, and collecting data at sea. In the first half of the thesis, I examine the role of mesoscale physical features in shaping phytoplankton community structure and influencing rates of primary production. I compare the output of a complex marine ecosystem model coupled to coarse resolution and eddy-permitting physical models. Explicitly resolving eddies resulted in marked regional variations in primary production, zooplankton and phytoplankton biomass. The same phytoplankton phenotypes persisted in both cases, and were dominant in the same regions. Global phytoplankton diversity was unchanged. However, levels of local phytoplankton diversity were markedly different, with a large increase in local diversity in the higher resolution model. Increased diversity could be attributed to a combination of enhanced dispersal, environmental variability and nutrient supply in the higher resolution model. Diversity "hotspots" associated with western boundary currents and coastal upwelling zones are sustained through a combination of all of these factors. In the second half of the thesis I describe the results of a fine scale ecological and biogeochemical survey of the Kuroshio Extension Front. I found fine scale patterns in physical, chemical and biological properties that can be linked back to both the large scale horizontal and smaller scale vertical physical dynamics of the study region. A targeted genomic analysis of samples focused on the ecology of the picoeukaryote Ostreococcus clade distributions strongly supports the model derived hypotheses about the mechanisms supporting diversity hotspots. Strikingly, two distinct clades of Ostreococcus co-occur in more than half of the samples. A "hotspot" of Ostreococcus diversity appears to be supported by a confluence of water masses containing either clade, as well as a local nutrient supply at the front and the mesoscale variability of the region.
Download or read book Real time Coastal Observing Systems for Marine Ecosystem Dynamics and Harmful Algal Blooms written by Babin, Marcel and published by UNESCO. This book was released on 2008-06-05 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proliferation of harmful phytoplankton in marine ecosystems can cause massive fish kills, contaminate seafood with toxins, impact local and regional economies and dramatically affect ecological balance. Real-time observations are essential for effective short-term operational forecasting, but observation and modelling systems are still being developed. This volume provides guidance for developing real-time and near real-time sensing systems for observing and predicting plankton dynamics, including harmful algal blooms, in coastal waters. The underlying theory is explained and current trends in research and monitoring are discussed.Topics covered include: coastal ecosystems and dynamics of harmful algal blooms; theory and practical applications of in situ and remotely sensed optical detection of microalgal distributions and composition; theory and practical applications of in situ biological and chemical sensors for targeted species and toxin detection; integrated observing systems and platforms for detection; diagnostic and predictive modelling of ecosystems and harmful algal blooms, including data assimilation techniques; observational needs for the public and government; and future directions for research and operations.
Download or read book Applied Turbulence Modelling in Marine Waters written by Hans Burchard and published by Springer Science & Business Media. This book was released on 2002-09-23 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: The simulation of turbulent mixing processes in marine waters is one of the most pressing tasks in oceanography. It is rendered difficult by the various complex phenomena occurring in these waters like strong stratification, ex ternal and internal waves, wind generated turbulence, Langmuir circulation etc. The need for simulation methods is especially great in this area because the physical processes cannot be investigated in the laboratory. Tradition ally, empirical bulk type models were used in oceanography, which, however, cannot account for many of the complex physical phenomena occurring. In engineering, statistical turbulence models describing locally the turbulence mixing processes were introduced in the early seventies, such as the k E model which is still one of the most widely used models in Computational Fluid Dy namics. Soon after, turbulence models were applied more and more also in the atmospheric sciences, and here the k kL model of Mellor and Yamada became particularly popular. In oceanography, statistical turbulence mod els were introduced rather late, i. e. in the eighties, and mainly models were taken over from the fields mentioned above, with some adjustments to the problems occurring in marine waters. In the literature on turbulence model applications to oceanography problems controversial findings and claims are reported about the various models, creating also an uncertainty on how well the models work in marine water problems.
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 Biological Oceanography of the Baltic Sea written by Pauline Snoeijs-Leijonmalm and published by Springer Science & Business Media. This book was released on 2017-04-04 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first comprehensive science-based textbook on the biology and ecology of the Baltic Sea, one of the world’s largest brackish water bodies. The aim of this book is to provide students and other readers with knowledge about the conditions for life in brackish water, the functioning of the Baltic Sea ecosystem and its environmental problems and management. It highlights biological variation along the unique environmental gradients of the brackish Baltic Sea Area (the Baltic Sea, Belt Sea and Kattegat), especially those in salinity and climate. pt;font-family:"Arial","sans-serif"; color:#262626">The first part of the book presents the challenges for life processes and ecosystem dynamics that result from the Baltic Sea’s highly variable recent geological history and geographical isolation. The second part explains interactions between organisms and their environment, including biogeochemical cycles, patterns of biodiversity, genetic diversity and evolution, biological invasions and physiological adaptations. In the third part, the subsystems of the Baltic Sea ecosystem – the pelagic zone, the sea ice, the deep soft sea beds, the phytobenthic zone, the sandy coasts, and estuaries and coastal lagoons – are treated in detail with respect to the structure and function of communities and habitats and consequences of natural and anthropogenic constraints, such as climate change, discharges of nutrients and hazardous substances. Finally, the fourth part of the book discusses monitoring and ecosystem-based management to deal with contemporary and emerging threats to the ecosystem’s health.
Download or read book Modeling Coastal Hypoxia written by Dubravko Justic and published by Springer. This book was released on 2017-05-03 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a snapshot of representative modeling analyses of coastal hypoxia and its effects. Hypoxia refers to conditions in the water column where dissolved oxygen falls below levels that can support most metazoan marine life (i.e., 2 mg O2 l-1). The number of hypoxic zones has been increasing at an exponential rate since the 1960s; there are currently more than 600 documented hypoxic zones in the estuarine and coastal waters worldwide. Hypoxia develops as a synergistic product of many physical and biological factors that affect the balance of dissolved oxygen in seawater, including temperature, solar radiation, wind, freshwater discharge, nutrient supply, and the production and decay of organic matter. A number of modeling approaches have been increasingly used in hypoxia research, along with the more traditional observational and experimental studies. Modeling is necessary because of rapidly changing coastal circulation and stratification patterns that affect hypoxia, the large spatial extent over which hypoxia develops, and limitations on our capabilities to directly measure hypoxia over large spatial and temporal scales. This book consists of 15 chapters that are broadly organized around three main topics: (1) Modeling of the physical controls on hypoxia, (2) Modeling of biogeochemical controls and feedbacks, and, (3) Modeling of the ecological effects of hypoxia. The final chapter is a synthesis chapter that draws generalities from the earlier chapters, highlights strengths and weaknesses of the current state-of-the-art modeling, and offers recommendations on future directions.
Download or read book Marine Ecosystem Dynamics Models Construction Application And Development written by Honghua Shi and published by World Scientific. This book was released on 2023-09-13 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the fundamental theories, methodologies and case studies of marine ecosystem modeling with a special focus on marine ecological dynamics that could provide scientists and researchers with a stabile and reliabile technical framework to study marine life and their developments.This book also clarifies the research objective and model classification methods of marine ecosystem dynamics research and analyzes the key marine ecological processes that affect modeling. The technical framework for improving the performance of modeling is also proposed, and the latest progress in research, as well as existing difficulties and challenges in end-to-end dynamics models are reviewed and analyzed. A dimensionality reduction theorem is established and derived for analyzing the stability of the solutions of a class of self-conserving marine ecosystem dynamic models. Also included in this work are several new types of marine ecosystem dynamics models constructed by modern computing methods — including artificial neural networks, cellular automata, and statistical dynamics — and case studies.This book is a suitable reference for professional and technical personnel, managers and graduate students specializing in the evolution mechanism, simulation, predication and regulation of marine ecosystems.
Download or read book Phytoplankton in Surface Ocean Fronts written by Alain Joseph De Verneil and published by . This book was released on 2015 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Phytoplankton at fronts are subjected to physical forcing at multiple spatiotemporal scales. To better understand why phytoplankton are distributed where they are in a front, and determine whether phytoplankton undergo net growth or decay, my dissertation focuses on characterizing the physical motions at fronts and the rates of change of phytoplankton. To quantify the rate of change of phytoplankton, I developed a "pseudo-Lagrangian" method that tracks biological tracers, allowing the calculation of net specific rates of growth. The method increases the number and spatial coverage of rate estimates relative to traditional methods. I also derived error estimates for these rates. Applying this method to other tracers will significantly increase the number of rate estimates that can be used, for example, as constraints in biogeochemical budgets. Using high-resolution hydrographic data from a front, I identified fine-scale features in the phytoplankton distribution. I diagnosed cross-frontal vertical velocity shear as the responsible mechanism. A plausible source for this shear was ageostrophic forcing from frontogenesis upstream. Using remote sensing and scaling arguments, I calculated the timescale of the relevant forcing. This shearing mechanism converts existing horizontal gradients into vertical gradients, with consequences for phytoplankton and for zooplankton grazers. Future phytoplankton studies at fronts will have to consider this mechanism and the structures it produces. I also surveyed two submesoscale instabilities at fronts, and diagnosed their impacts on phytoplankton communities. The short timescales of the instabilities have precluded field observation until recently, and modeling studies have only recently resolved their dynamics. Exploration of the biological impacts of these specific instabilities via models or observations remains to be conducted. Therefore, by characterizing the motion, prerequisite conditions, and biological impacts of instabilities, I communicated their dynamics to the community of biological oceanographers in order to stimulate research to address this gap in knowledge. The results from this dissertation can thus be applied in future observational and modeling studies of phytoplankton at fronts: markedly increasing the number of in situ growth rate measurements, aiding in the identification of mechanisms structuring phytoplankton distributions, and providing a guide for investigating the rapid changes of phytoplankton within regions of flow instabilities.
Download or read book The Global Coastal Ocean written by James J. McCarthy and published by Harvard University Press. This book was released on 2005 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oceanography and Marine Biology written by R. N. Gibson and published by CRC Press. This book was released on 2006-06-13 with total page 542 pages. Available in PDF, EPUB and Kindle. Book excerpt: With increasing interest in the field and its relevance in global environmental issues, Oceanography and Marine Biology: An Annual Review provides authoritative reviews that summarize results of recent research in basic areas of marine research, exploring topics of special and topical importance while adding to new areas as they arise. This volume, part of a series that regards the all marine sciences as a complete unit, features contributions from experts involved in biological, chemical, geological, and physical aspects of marine science. Including a full color insert and an extensive reference list, the text is an essential reference for researchers and students in all fields of marine science.