Download or read book On the Response of Marine Phytoplankton to Changing Nutrient and Light Conditions written by Katherine Rose Marie Mackey and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine phytoplankton are photoautotrophic microorganisms that synthesize organic biomass from mineral nutrients and form the base of the marine food web. Marine phytoplankton are increasingly being recognized as important contributors to biogeochemical cycling of chemical elements, including carbon (C), and therefore play a role in controlling Earth's climate. A relatively recent estimate suggests that while the upper 100 meters of the ocean contains less than 1 percent of the total global photosynthetic biomass, this small fraction of the marine environment accounts for nearly 50 percent of global primary production, the process by which atmospheric carbon dioxide is incorporated into biomass through photosynthesis. Nutrients and light affect phytoplankton growth, and their availability exerts considerable control on phytoplankton distributions in the ocean and their contribution to biogeochemical cycles. The global supply, distribution, and availability of nutrients in the ocean are driven by a range of physical and biological factors. However, light availability is determined primarily by attenuation within the water column. The ability of a phytoplankton group to respond to changes in nutrient and light availability ultimately determines whether that group will persist, or whether community succession will permit different, more ecologically competitive groups to prevail. The overarching goal of this dissertation is to identify and understand how responses to changing resource availability influence the competitive success of phytoplankton, and to increase our understanding of how phytoplankton affect biogeochemical cycling of C and other important nutrients in the ocean. The dissertation includes an Introduction (Chapter 1), and seven research chapters (Chapters 2-8) covering separate bodies of work, each focusing on a different topic as outlined below. In Chapter 1, general background information is provided about nutrient and light regimes in the ocean, and about the basic biology and ecology of phytoplankton. Chapter 2 (entitled: The phosphorus cycle) provides an overview of the phosphorus (P) cycle including sources, sinks, and transport pathways of P in the environment, microbially-mediated processes and their genetic regulation, methods for assessing environmental P concentrations and microbial phosphate status, and a discussion of microbial responses to anthropogenic changes to the P cycle. This chapter was published in 2009 in The Encyclopedia of Microbiology, 3rd Edition, edited by Moselio Schaechter, Elsevier. Chapter 3 is entitled: Phosphorus availability, phytoplankton community dynamics, and taxon-specific phosphorus status in the Gulf of Aqaba, Red Sea. The study uses a novel cell stain to show that (1) coexisting groups of phytoplankton exposed to identical phosphate levels may have a different phosphate status, and (2) although increased alkaline phosphatase activity can serve as an indicator of phosphate limitation, it does not necessarily confer a competitive advantage to cells in oligotrophic waters, where smaller cell size may provide a more important competitive edge. The affinity of individual groups of phytoplankton for P may help determine community composition and lead to seasonal community succession as P availability changes dramatically throughout the year. This chapter was published in 2007 in Limnology and Oceanography 52: 873-885. Chapter 4 is entitled: Nitrogen cycling in oligotrophic waters: the influence of light and substrate availability. This study demonstrates that two major processes contribute to formation of nitrite maxima in the Gulf of Aqaba: (i) spatially segregated microbial oxidation of ammonium and nitrite during nitrification; and (ii) incomplete nitrate reduction to ammonium by light-limited phytoplankton. Field data and stable isotope (N-15) tracer experiments show that physical and biological characteristics of the water column determine which of the two nitrite formation processes becomes dominant at a given season and depth. Rates are reported for major N transformation reactions occurring in the N cycle. This chapter is currently in review with Limnology and Oceanography. Chapter 5 is entitled: Picophytoplankton responses to changing nutrient and light regimes during a bloom. In the Red Sea, the spring bloom is characterized by a rapid increase in photosynthetic biomass. Nutrient addition experiments and in situ monitoring show that picoeukaryotes and Synechococcus have a bloomer growth strategy, have higher P requirements relative to N, and are responsible for the majority of photosynthetic biomass in surface waters. In contrast, light limited populations show rapid photoacclimation and community shifts following stratification. The traditional interpretation of "bloom" dynamics (i.e. increase in biomass) may therefore be confined to surface waters where light is not limiting, while other acclimation processes are more ecologically relevant at depth. This chapter was published in 2009 in Marine Biology 156: 1531-1546. Chapter 6 is entitled: A photosynthetic strategy for coping in a high light, low nutrient environment. This chapter reports field observations from the Atlantic and Pacific Oceans that show the reduction of oxygen is important for preserving photosynthetic efficiency in oligotrophic waters where low Fe levels may limit PSI and cytochrome b6f biogenesis. Despite midday photoinhibition (depression in the maximum photochemical yield, Fv/Fm), cells do not show a decreased capacity for carbon dioxide fixation. Instead, the fraction of oxidized functional PSII reaction centers increases at midday, counteracting the loss of functional centers stemming from photoinhibition. This process was not apparent in the coastal phytoplankton populations monitored in this study, and may be a strategy unique to open ocean phytoplankton. This chapter was published in 2008 in Limnology and Oceanography 53: 900-913. Chapter 7 is entitled: The influence of atmospheric nutrients on primary productivity in a coastal upwelling region. This chapter is the first study to quantify the role of atmospheric deposition in supporting productivity an upwelling-dominated system (coastal California). Soluble nutrient measurements from locally-collected aerosols, oceanographic and atmospheric data from long-term monitoring programs and the MODIS satellite record, and laboratory culture experiments are used. The aerosol-Chlorophyll a relationship is significant in the summer, and is stronger at offshore locations than near the coast. Atmospheric nutrient sources are more important during El Niño periods when upwelling is suppressed, a phenomenon that may become more common due to climate warming. During high deposition non-upwelling periods aerosol N could support up to 20 percent of new production. Expanding our analysis to other regions, we find that atmospheric deposition may support up to 8 percent of production annually in other major coastal upwelling regions around the world. This chapter is currently in review with Global Biogeochemical Cycles. Chapter 8 is entitled: Toxicity of metals on marine Synechococcus. Atmospheric deposition of aerosols to the surface ocean is a source of nutrients for phytoplankton. However, this study demonstrates that atmospheric aerosols also contain components like copper (Cu), which are toxic to some phytoplankton above certain threshold levels. Incubations of natural phytoplankton assemblages with local aerosols show that metal toxicity can cause a major shift in phytoplankton community composition, suggesting that atmospheric aerosols may play a larger role in controlling phytoplankton species distributions than previously believed. Specific metal toxicity threshold concentrations were determined based on laboratory culture experiments with coastal and oceanic strains of Synechococcus, and oceanic strains are more susceptible to metal toxicity at lower concentrations and for a larger number of metals. A portion of this chapter was published as part of a larger study that also included a global model for Cu deposition in aerosols that was published in 2009 in The Proceedings of the National Academy of Science 106: 4601-4605 Chapter 9 discusses ideas for future work. The dissertation provides valuable information about how phytoplankton respond to resource availability in a number of different marine environments. The physical environment is shown to play an important role in determining nutrient and light availability over short term periods (e.g. transient exposure to high light during mixing, episodic delivery of aerosol nutrients) as well as over predictable seasonal cycles (e.g. deep convective mixing and stratification). Physiological acclimation of individual phytoplankton to these perturbations allows each species to survive over a broader range of conditions, increasing their competitive advantage. Similarly, succession allows the phytoplankton community as a whole to thrive over the broadest possible range of environmental conditions. This dissertation also shows that phytoplankton play an important role in the P and N cycles by generating organic substrates from inorganic substrates. In doing so, phytoplankton contribute substantially to primary production in coastal and open ocean habitats, and form and important link between the biotic and abiotic environment.

Download or read book YOUMARES 8 Oceans Across Boundaries Learning from each other written by Simon Jungblut and published by Springer. This book was released on 2018-08-29 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book presents the proceedings volume of the YOUMARES 8 conference, which took place in Kiel, Germany, in September 2017, supported by the German Association for Marine Sciences (DGM). The YOUMARES conference series is entirely bottom-up organized by and for YOUng MARine RESearchers. Qualified early career scientists moderated the scientific sessions during the conference and provided literature reviews on aspects of their research field. These reviews and the presenters’ conference abstracts are compiled here. Thus, this book discusses highly topical fields of marine research and aims to act as a source of knowledge and inspiration for further reading and research.

Download or read book Sensitivity of Phytoplankton to Climate Change written by Miriam Seifert and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine phytoplankton constitutes about half of the primary production on Earth. It forms the base of the marine food web and is a pivotal player in the marine biological carbon pump. The primary environmental drivers that control phytoplankton growth are temperature, nutrient availability, light, and the concentration of inorganic carbon species. Ongoing climate change modifies these drivers, leading to a warming, high-CO2 ocean with altered nutrient availabilities and light regimes. Changes in phytoplankton productivity and community composition resulting from these newly emerging environmental states in the ocean have important implications for the marine ecosystem and carbon cycling. Biogeochemical ocean models are used to investigate how marine primary production may be affected by future climate change under different emission scenarios. Phytoplankton growth rates in models are typically determined by functions describing growth dependencies on temperature, light, and nutrients. However, a large body of laboratory studies on phytoplankton responses to environmental drivers reveals two points that are usually not considered in current biogeochemical models. Firstly, phytoplankton growth can be considerably modified by the state of the carbonate system. Changes in inorganic carbon species concentrations can be either growth-enhancing (CO2(aq) and bicarbonate are substrates for photosynthesis), or growth-dampening (increasing CO2(aq) levels lead to a shift in the carbonate equilibria and result in a pH decrease, a process which is called ocean acidification). Functions describing this growth dependence of phytoplankton on the carbonate system have not been implemented in large-scale ocean biogeochemical models so far. Secondly, growth responses towards one driver can be modified if the level of another driver is changing. Functions including these so-called interactive driver effects partly exist in models (e.g. the response to varying light levels may depend on the nutrient limitation term). However, the large number of laboratory studies on multiple driver effects has never been used to constrain driver interactions in large-scale ocean biogeochemical models. This holds especially true for the findings of growth responses to driver interactions that include ocean acidification, which make up the largest share of laboratory experiments. This thesis aims to investigate sensitivities of marine phytoplankton to changing CO2(aq) levels as well as to interactive effects between CO2 and other environmental drivers. A comprehensive and reproducible literature search in combination with a statistical analysis (Publication I) reveals that increasing CO2(aq) levels robustly dampen the growth-increasing effects of warming and improving light conditions. In addition, the results show that the calcifying phytoplankton group of coccolithophores experiences the strongest negative effects by ocean acidification compared to other phytoplankton groups. A second study (Publication II) examines the effects of mechanistically described carbonate system dependencies on primary production and community composition in a model. To this end, carbonate system dependencies of phytoplankton growth and and coccolithophore calcification are implemented into the global biogeochemical ocean model REcoM. The study shows that responses to ocean acidification cascade on growth responses to other drivers, which partly balance or counteract the direct impact of the carbonate system on growth rates. In addition, warming is identified as the main driver of the observed recent increase of coccolithophore biomass in the North Atlantic. A final study (Publication III) investigates the interactive effects between CO2 and temperature as well as between CO2 and light on phytoplankton biomass and community composition in a high emission scenario. For the parametrization in REcoM, growth responses to interacting drivers as synthesized in Publication I are used. The decrease of global future phytoplankton biomass and net community production by the end of the century is similar in simulations with and without driver interactions (-6% and -8%, respectively). However, phytoplankton responses to future climate conditions are considerably modified on a regional scale and the share of individual phytoplankton groups in the community changes both globally and regionally when accounting for multiple driver effects. Globally, diatoms and coccolithophores are impacted more and small phytoplankton less severely by future oceanic conditions when accounting for driver interactions. Future projections of the Southern Ocean phytoplankton community are modified most dramatically with the new interactive growth formulation, as diatoms and coccolithophores become less and small phytoplankton more abundant, while it is the other way round in simulations without driver interactions. The thesis highlights 1) that the carbonate system is a critical growth-modifying driver for phytoplankton in a high-CO2 ocean, which can furthermore modify growth responses to other drivers substantially, and 2) that driver interactions have considerable effects on climate-change induced alterations in the phytoplankton community as well as on regional biomass changes in a future ocean.

Download or read book Ecology and the Environment written by Russell K. Monson and published by Springer. This book was released on 2014-10-02 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, plant biology is considered from the perspective of plants and their surrounding environment, including both biotic and abiotic interactions. The intended audience is undergraduate students in the middle or final phases of their programs of study. Topics are developed to provide a rudimentary understanding of how plant-environment interactions span multiple spatiotemporal scales, and how this rudimentary knowledge can be applied to understand the causes of ecosystem vulnerabilities in the face of global climate change and expansion of natural resource use by human societies. In all chapters connections are made from smaller to larger scales of ecological organization, providing a foundation for understanding plant ecology. Where relevant, environmental threats to ecological systems are identified and future research needs are discussed. As future generations take on the responsibility for managing ecosystem goods and services, one of the most effective resources that can be passed on is accumulated knowledge of how organisms, populations, species, communities and ecosystems function and interact across scales of organization. This book is intended to provide some of that knowledge, and hopefully provide those generations with the ability to avoid some of the catastrophic environmental mistakes that prior generations have made.

Download or read book Plankton Ecology written by Ulrich Sommer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: All relevant ecological aspects of plankton, especially seasonal changes in the species composition, the role of competition for limiting resources in species replacements, the role of parasitism, predation and competition in seasonal succession are treated in detail considering phytoplankton, zooplankton and bacteroplankton. In addition to its use as a valid reference book for plankton ecology, this monograph may well be used as a model for other kinds of ecological communities.

Download or read book The Ecology of Phytoplankton written by C. S. Reynolds and published by Cambridge University Press. This book was released on 2006-05-04 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: This important new book by Colin Reynolds covers the adaptations, physiology and population dynamics of phytoplankton communities. It provides basic information on composition, morphology and physiology of the main phyletic groups represented in marine and freshwater systems and in addition reviews recent advances in community ecology.

Download or read book Ocean Acidification written by National Research Council and published by National Academies Press. This book was released on 2010-09-14 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ocean has absorbed a significant portion of all human-made carbon dioxide emissions. This benefits human society by moderating the rate of climate change, but also causes unprecedented changes to ocean chemistry. Carbon dioxide taken up by the ocean decreases the pH of the water and leads to a suite of chemical changes collectively known as ocean acidification. The long term consequences of ocean acidification are not known, but are expected to result in changes to many ecosystems and the services they provide to society. Ocean Acidification: A National Strategy to Meet the Challenges of a Changing Ocean reviews the current state of knowledge, explores gaps in understanding, and identifies several key findings. Like climate change, ocean acidification is a growing global problem that will intensify with continued CO2 emissions and has the potential to change marine ecosystems and affect benefits to society. The federal government has taken positive initial steps by developing a national ocean acidification program, but more information is needed to fully understand and address the threat that ocean acidification may pose to marine ecosystems and the services they provide. In addition, a global observation network of chemical and biological sensors is needed to monitor changes in ocean conditions attributable to acidification.

Download or read book Photosynthesis in Algae Biochemical and Physiological Mechanisms written by Anthony W.D. Larkum and published by Springer Nature. This book was released on 2020-06-03 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: Algae, including cyanobacteria, are in the spotlight today for a number of reasons; firstly it has become abundantly clear over recent years that algae have been neglected in terms of basic research and that knowledge gap is being rapidly closed with the establishment of some surprising discoveries, such as the presence of Near-Infra-Red-Absorbing cyanobacteria and a wealth of natural products; secondly molecular approaches have provided a wealth of approaches to genetically modify algae and produce value-added products; thirdly it has become clear just how important, marine phytoplankton is to global carbon capture and the production of food globally; and fourthly, it has also become clear that algae present unparalleled opportunities to generate biofuels in a sustainable and non-polluting way. This volume presents 15 chapters by world experts on their subjects, ranging from reviews of algal diversity and genetics to in-depth reviews of special algal groups such as diatoms (which account for over 30% of marine carbon capture). Other chapters chart the ways in which this carbon capture occurs or how there are a multiplicity of ways in which algae intercept sun light and deploy this energy for carbon capture. A fascinating aspect here is the way in which sun light is harvested. A special chapter is devoted to the very recent and exciting possibility that algae use coherent light energy transformation to enhance the efficiency of light capture, an aspect of quantum physics that has implications for future developments at several levels and a variety of industries. Just how and why algae use Chlorophyll a as the major light capture pigment is discussed in several chapters. However, attention is also given to those cyanobacteria, which have been found to use the special Near-Infra Red absorbing chlorophylls mentioned above. And attention is also given to those algae that employ phycobiliproteins to fill in the “green window”, i.e., the spectral region from 400 – 650 nm, which is not efficiently covered by chlorophyll and carotenoid pigments. Photoinhibition and photoprotection is the subject area of several chapters and one which it is essential to understand a we work towards greater efficiency of algal photosynthesis. A final chapter is devoted to understanding the molecular basis for coral bleaching, a much-neglected area that is essential in trying to come up with solutions to this very worrying phenomenon, caused by global warming and ocean acidification. This is a book for research scientists, environmentalists, planners in a range of areas including those of marine resources, nutrient control and pollution of water bodies and that growing body of concerned citizens interested in controlling carbon emissions and global warming. Special attention has been given to generating a set of articles that will be read by university students, informed laymen and all those whose wish to understand the rapid changes that have come about in our knowledge of algae over the past decade.

Download or read book Ecophysiological Responses of Phytoplankton to Environmental Cues a Laboratory Approach written by Tristyn Bercel and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Phytoplankton are primary producers in the marine food web, providing energy and matter for higher trophic levels by fixing CO2 and inorganic nutrients into biomass. This production of particulate organic matter by marine phytoplankton, its consumption by higher trophic levels, and the eventual export out of the euphotic zone drive the biological carbon pump. Marine phytoplankton thus simultaneously exert influence over and are influenced by global biogeochemical cycles. The effects of changing environmental conditions, such as light, temperature, and CO2 concentration, play a key role in shaping phytoplankton community structure and function. Responses to environmental change vary between phytoplankton taxa, and even within species, making predictions of such responses difficult. Therefore, we need to understand how and why phytoplankton photosynthesis responds to environmental cues. Investigation of the ecophysiological responses of phytoplankton is often done in laboratory studies where environmental conditions are mimicked in growth incubators. Recently, LED technology has advanced, leading many incubator manufacturers and research labs to switch to these more efficient, yet spectrally restricted, light sources. The effects of commercially available light systems on phytoplankton ecophysiology have not yet been characterized but could affect our interpretation of lab-based projections on responses to environmental changes. We investigated these effects with cultures of Prochlorococcus marinus, Synechococcus sp., and Thalassiosira weissflogii grown under three different commercially available LED lights along with a fluorescent growth light. We found that growth rate was unaffected across species, however, each species responded with adjustments to cellular chlorophyll a, carbon, and nitrogen quotas, photoacclimation state, and primary production. These cellular acclimation responses should be considered when designing laboratory-based incubation experiments to mimic the natural environment. Next, I investigated carbon acquisition in the red tide forming marine dinoflagellate, Karenia brevis. K. brevis is commonly found in the Gulf of Mexico and produces brevetoxin, a potent neurotoxin which can cause mortality in marine animals as well as respiratory illness in humans, making it an ecologically and economically relevant species. Previous work done on K. brevis had shown sensitivity to changes in CO2 in terms of growth and toxin production. I investigated the underlying mechanisms, including photosynthesis, inorganic carbon acquisition, and photophysiology, to understand this sensitivity. K. brevis (CCFWC-126) did not show a significant response in growth, cellular composition of carbon and nitrogen, nor in photosynthetic rates between pCO2 concentrations of 150, 400 or 780 μatm. However, a strong response in its acquisition of inorganic carbon was found. Half saturation values for CO2 increased, inorganic carbon preference switched from HCO3- to CO2, and external carbonic anhydrase activity was downregulated when comparing low and high pCO2. I thus demonstrated the presence of an efficient and regulated carbon concentrating mechanism (CCM) in K. brevis. This study is the first explaining how this socioeconomically important species can efficiently supply inorganic carbon for photosynthesis which can potentially prolong bloom situations. Like many other marine dinoflagellates, previous work has demonstrated the use of mixotrophic metabolic strategies in K. brevis, including the uptake of dissolved organic matter as well as grazing on picocyanobacteria. While it has been demonstrated that K. brevis is capable of multiple nutritional strategies, the balance of autotrophy and heterotrophy during mixotrophic growth has not been examined. We investigated the uptake of several DOM sources in K. brevis CC-FWC126 using isotopic labeling techniques and quantification of photosynthetic activity. Additionally, we examined metatranscriptomes for multiple K. brevis isolates to survey the extent of mixotrophic ability. While we did not obtain conclusive proof of DOM utilization by K. brevis in our lab, this does not preclude its ability to utilize DOM under conditions not presently measured. Changes seen in cellular chl a and photophysiological adjustments do suggest that DOM affects energy generation in K. brevis, but the present study was unable to determine the cause of these changes in relation to changes in nutritional mode. We also cannot rule out the role of bacterial regeneration in the culture bottles despite the cleaning of cultures, which could mediate the DOM breakdown process, influencing what is available to K. brevis uptake. Metatranscriptome analysis for 4 K. brevis clones revealed the presence and expression of genes for DOM transporters and degradation enzymes as well as genes involved in phagotrophy in all transcriptomes, suggesting mixotrophy is a common trait among K. brevis clones. I then discuss the ecophysiology implications for mixotrophy in K. brevis and how this might affect bloom life cycles.

Download or read book Clean Coastal Waters written by National Research Council and published by National Academies Press. This book was released on 2000-08-17 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental problems in coastal ecosystems can sometimes be attributed to excess nutrients flowing from upstream watersheds into estuarine settings. This nutrient over-enrichment can result in toxic algal blooms, shellfish poisoning, coral reef destruction, and other harmful outcomes. All U.S. coasts show signs of nutrient over-enrichment, and scientists predict worsening problems in the years ahead. Clean Coastal Waters explains technical aspects of nutrient over-enrichment and proposes both immediate local action by coastal managers and a longer-term national strategy incorporating policy design, classification of affected sites, law and regulation, coordination, and communication. Highlighting the Gulf of Mexico's "Dead Zone," the Pfiesteria outbreak in a tributary of Chesapeake Bay, and other cases, the book explains how nutrients work in the environment, why nitrogen is important, how enrichment turns into over-enrichment, and why some environments are especially susceptible. Economic as well as ecological impacts are examined. In addressing abatement strategies, the committee discusses the importance of monitoring sites, developing useful models of over-enrichment, and setting water quality goals. The book also reviews voluntary programs, mandatory controls, tax incentives, and other policy options for reducing the flow of nutrients from agricultural operations and other sources.

Download or read book Metabolic Ecology written by Richard M. Sibly and published by John Wiley & Sons. This book was released on 2012-04-30 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metabolic Ecology Most of ecology is about metabolism, the ways that organisms use energy and materials. The energy requirements of individuals (their metabolic rates) vary predictably with their body size and temperature. Ecological interactions are exchanges of energy and materials between organisms and their environments. Therefore, metabolic rate affects ecological processes at all levels: individuals, populations, communities and ecosystems. Each chapter focuses on a different process, level of organization, or kind of organism. It lays a conceptual foundation and presents empirical examples. Together, the chapters provide an integrated framework that holds the promise for a unified theory of ecology. The book is intended to be accessible to upper-level undergraduates and graduate students, but also of interest to senior scientists. Its easy-to-read chapters and clear illustrations can be used in lecture and seminar courses. This is an authoritative treatment that will inspire future generations to study metabolic ecology.

Download or read book Coccolithophores written by Hans R. Thierstein and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 567 pages. Available in PDF, EPUB and Kindle. Book excerpt: This introduction to one of the most common phytoplankton types provides broad coverage from molecular and cellular biology all the way to its impact on the global carbon cycle and climate. Individual chapters focus on coccolithophore biology, ecology, evolutionary phylogeny and impact on current and past global changes. The book addresses fundamental questions about the interaction between the biota and the environment at various temporal and spatial scales.

Download or read book Global Ecology and Oceanography of Harmful Algal Blooms written by Patricia M. Glibert and published by Springer. This book was released on 2018-04-26 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt: Harmful algal blooms (HABs) - blooms that cause fish kills, contaminate seafood with toxins, or cause human or ecological health impacts and harm to local economies - are occurring more often, in more places and lasting longer than in past decades. This expansion is primarily the result of human activities, through increased nutrient inputs and various aspects of climate change. The Global Ecology and Oceanography of Harmful Algal Blooms (GEOHAB) programme promoted international collaboration to understand HAB population dynamics in various oceanographic regimes and to improve the prediction of HABs. This volume introduces readers to the overarching framework of the GEOHAB programme, factors contributing to the global expansion of harmful algal blooms, the complexities of HABs in different habitats, and the forward-looking issues to be tackled by the next generation of GEOHAB, GlobalHAB. The programme brought together an international team of contributing scientists and ecosystem managers, and its outcomes will greatly benefit the international research community.

Download or read book Influence of Climate Change on the Changing Arctic and Sub Arctic Conditions written by Jacques Nihoul and published by Springer. This book was released on 2009-01-25 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: The current warming trends in the Arctic may shove the Arctic system into a seasonally ice-free state not seen for more than one million years. The melting is accelerating, and researchers were unable to identify natural processes that might slow the deicing of the Arctic. Such substantial additional melting of Arctic and Antarctic glaciers and ice sheets would raise the sea level worldwide, flooding the coastal areas where many of the world's population lives. Studies, led by scientists at the National Center for Atmospheric Research (NCAR) and the University of Arizona, show that greenhouse gas increases over the next century could warm the Arctic by 3-5°C in summertime. Thus, Arctic summers by 2100 may be as warm as they were nearly 130,000 years ago, when sea levels eventually rose up to 6 m higher than today.

Download or read book Upwelling Ecosystems written by R. Boje and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: Upwelling areas are among the most fertile regions of the ocean. In principle, upwelling is caused by the divergence of the flow in the surface layer of the ocean which arises as a consequence of a particular wind field, the presence of a coastline, or other special conditions. Since deeper oceanic layers are usually enriched wi th nutrients, it is the permanent supply of nutrients which forms the basis for the high producti vi ty of upwelling reg ions. The study of upwelling and its consequences were, for a long time, the task of individual scientists from all disciplines of marine science. Today, it is perhaps the branch of oceanography where interdisciplinary coopera tion has developed best. Becoming aware of the large potential yield of upwelling regions, governments in creased the funds for upwelling research. With research activities developed on a larger scale, interdisciplin ary cooperation became a necessity. On the international level, several symposia documented the rapid development. Three volumes reflect the results of these scientific meetings (Rapp. Proc.-Verb. 159, 1970; Inv. Pesq. 35, 1, 1971; Tethys §.' 1-2, 1974). The present book contains selected papers from the Third Symposium on Upwelling Ecosystems, which was held in Kiel in September 1975. Although the third of a series of meetings, it was the first where the word "ecosystem" stood in the title for a scientific program.

Download or read book Changing Plankton Communities Causes Effects and Consequences written by Kristian Spilling and published by Frontiers Media SA. This book was released on 2019-10-04 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine ecosystems are changing at an unprecedented rate. In addition to the direct effects of e.g. warming surface temperatures, the environmental changes also cause shifts in plankton communities. Plankton makes up the base of the marine food web and plays a pivotal role in global biogeochemical cycles. Any shifts in the plankton community composition could have drastic consequences for marine ecosystem functioning. This Research Topic focuses on causes, effects and consequences of such shifts in the plankton community structure.

Download or read book Coastal Hypoxia written by Nancy N. Rabalais and published by American Geophysical Union. This book was released on 2001-01-09 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hypoxia occurs when dissolved oxygen falls below the level necessary to sustain most animal life, often due to fertilizer run-off. This volume reviews how the expanding hypoxic zone in the northern Gulf of Mexico has affected living resources in the Louisiana/Texas shelf. Topics of the 23 chapters include impacts of changing Si/N ratios and phytoplankton species composition, the effect of hypoxia and anoxia on the supply and settlement of benthic invertebrate larvae, and ecological effects of hypoxia in fish, sea turtles, and marine mammals. c. Book News Inc.