OCN421 Lecture 9
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Probing the Changing Redfield Ratio of Phytoplankton
Probing the Changing Redfield Ratio of phytoplankton Supervisory Team Rosalind Rickaby www.earth.ox.ac.uk/people/rosalind-rickaby Katsumi Matsumoto www.esci.umn.edu/people/katsumi-matsumoto Key Research Question What controls the Redfield Ratio amongst algae? Overview under different conditions of Fe and C availability In 1934, Alfred Redfield made the notable to test the hypothesis that it is the nutrient observation that the relative ratios of C:N:P of efficiency of photosynthesis that dictates the C:N organic matter appeared to be constant throughout ratio of organic matter. the surface oceans, and also matched the Applicants would ideally have a background in dissolved ratios of those nutrients (C106N16P1). Biology/Chemistry/Earth Sciences or The Redfield ratio is fundamental in dictating the Environmental Sciences. strength of the biological sequestration of carbon, and the amount of oxygen that is used for respiration hence is an intimate control on the biotic feedback of phytoplankton on future climate. Despite efforts to understand the co-evolution of Methodology these ratios between the phytoplankton and the Methods to be used will include: Phytoplankton seawater from experimental, field observations Culture and sterile techniques, EA IRMS, and modelling efforts, there is still no mechanistic Spectrophotometry, and Microscopy. understanding of what drives the enormous variability seen across different phytoplankton lineages with various environmental conditions (Garcia et al., 2018). References & Further Reading Nature Geoscience -
A New Type of Plankton Food Web Functioning in Coastal Waters Revealed by Coupling Monte Carlo Markov Chain Linear Inverse Metho
A new type of plankton food web functioning in coastal waters revealed by coupling Monte Carlo Markov Chain Linear Inverse method and Ecological Network Analysis Marouan Meddeb, Nathalie Niquil, Boutheina Grami, Kaouther Mejri, Matilda Haraldsson, Aurélie Chaalali, Olivier Pringault, Asma Sakka Hlaili To cite this version: Marouan Meddeb, Nathalie Niquil, Boutheina Grami, Kaouther Mejri, Matilda Haraldsson, et al.. A new type of plankton food web functioning in coastal waters revealed by coupling Monte Carlo Markov Chain Linear Inverse method and Ecological Network Analysis. Ecological Indicators, Elsevier, 2019, 104, pp.67-85. 10.1016/j.ecolind.2019.04.077. hal-02146355 HAL Id: hal-02146355 https://hal.archives-ouvertes.fr/hal-02146355 Submitted on 3 Jun 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. 1 A new type of plankton food web functioning in coastal waters revealed by coupling 2 Monte Carlo Markov Chain Linear Inverse method and Ecological Network Analysis 3 4 5 Marouan Meddeba,b*, Nathalie Niquilc, Boutheïna Gramia,d, Kaouther Mejria,b, Matilda 6 Haraldssonc, Aurélie Chaalalic,e,f, Olivier Pringaultg, Asma Sakka Hlailia,b 7 8 aUniversité de Carthage, Faculté des Sciences de Bizerte, Laboratoire de phytoplanctonologie 9 7021 Zarzouna, Bizerte, Tunisie. -
7.014 Handout PRODUCTIVITY: the “METABOLISM” of ECOSYSTEMS
7.014 Handout PRODUCTIVITY: THE “METABOLISM” OF ECOSYSTEMS Ecologists use the term “productivity” to refer to the process through which an assemblage of organisms (e.g. a trophic level or ecosystem assimilates carbon. Primary producers (autotrophs) do this through photosynthesis; Secondary producers (heterotrophs) do it through the assimilation of the organic carbon in their food. Remember that all organic carbon in the food web is ultimately derived from primary production. DEFINITIONS Primary Productivity: Rate of conversion of CO2 to organic carbon (photosynthesis) per unit surface area of the earth, expressed either in terns of weight of carbon, or the equivalent calories e.g., g C m-2 year-1 Kcal m-2 year-1 Primary Production: Same as primary productivity, but usually expressed for a whole ecosystem e.g., tons year-1 for a lake, cornfield, forest, etc. NET vs. GROSS: For plants: Some of the organic carbon generated in plants through photosynthesis (using solar energy) is oxidized back to CO2 (releasing energy) through the respiration of the plants – RA. Gross Primary Production: (GPP) = Total amount of CO2 reduced to organic carbon by the plants per unit time Autotrophic Respiration: (RA) = Total amount of organic carbon that is respired (oxidized to CO2) by plants per unit time Net Primary Production (NPP) = GPP – RA The amount of organic carbon produced by plants that is not consumed by their own respiration. It is the increase in the plant biomass in the absence of herbivores. For an entire ecosystem: Some of the NPP of the plants is consumed (and respired) by herbivores and decomposers and oxidized back to CO2 (RH). -
Phytoplankton As Key Mediators of the Biological Carbon Pump: Their Responses to a Changing Climate
sustainability Review Phytoplankton as Key Mediators of the Biological Carbon Pump: Their Responses to a Changing Climate Samarpita Basu * ID and Katherine R. M. Mackey Earth System Science, University of California Irvine, Irvine, CA 92697, USA; [email protected] * Correspondence: [email protected] Received: 7 January 2018; Accepted: 12 March 2018; Published: 19 March 2018 Abstract: The world’s oceans are a major sink for atmospheric carbon dioxide (CO2). The biological carbon pump plays a vital role in the net transfer of CO2 from the atmosphere to the oceans and then to the sediments, subsequently maintaining atmospheric CO2 at significantly lower levels than would be the case if it did not exist. The efficiency of the biological pump is a function of phytoplankton physiology and community structure, which are in turn governed by the physical and chemical conditions of the ocean. However, only a few studies have focused on the importance of phytoplankton community structure to the biological pump. Because global change is expected to influence carbon and nutrient availability, temperature and light (via stratification), an improved understanding of how phytoplankton community size structure will respond in the future is required to gain insight into the biological pump and the ability of the ocean to act as a long-term sink for atmospheric CO2. This review article aims to explore the potential impacts of predicted changes in global temperature and the carbonate system on phytoplankton cell size, species and elemental composition, so as to shed light on the ability of the biological pump to sequester carbon in the future ocean. -
Relationships Between Net Primary Production, Water Transparency, Chlorophyll A, and Total Phosphorus in Oak Lake, Brookings County, South Dakota
Proceedings of the South Dakota Academy of Science, Vol. 92 (2013) 67 RELATIONSHIPS BETWEEN NET PRIMARY PRODUCTION, WATER TRANSPARENCY, CHLOROPHYLL A, AND TOTAL PHOSPHORUS IN OAK LAKE, BROOKINGS COUNTY, SOUTH DAKOTA Lyntausha C. Kuehl and Nels H. Troelstrup, Jr.* Department of Natural Resource Management South Dakota State University Brookings, SD 57007 *Corresponding author email: [email protected] ABSTRACT Lake trophic state is of primary concern for water resource managers and is used as a measure of water quality and classification for beneficial uses. Secchi transparency, total phosphorus and chlorophyll a are surrogate measurements used in the calculation of trophic state indices (TSI) which classify waters as oligotrophic, mesotrophic, eutrophic or hypereutrophic. Yet the relationships between these surrogate measurements and direct measures of lake productivity vary regionally and may be influenced by external factors such as non-algal tur- bidity. Prairie pothole basins, common throughout eastern South Dakota and southwestern Minnesota, are shallow glacial lakes subject to frequent winds and sediment resuspension. Light-dark oxygen bottle methodology was employed to evaluate vertical planktonic production within an eastern South Dakota pothole basin. Secchi transparency, total phosphorus and planktonic chlorophyll a were also measured from each of three basin sites at biweekly intervals throughout the 2012 growing season. Secchi transparencies ranged between 0.13 and 0.25 meters, corresponding to an average TSISD value of 84.4 (hypereutrophy). Total phosphorus concentrations ranged between 178 and 858 ug/L, corresponding to an average TSITP of 86.7 (hypereutrophy). Chlorophyll a values corresponded to an average TSIChla value of 69.4 (transitional between eutrophy and hypereutro- phy) and vertical production profiles yielded areal net primary productivity val- ues averaging 288.3 mg C∙m-2∙d-1 (mesotrophy). -
Fertilizing the Ocean with Iron Is This a Viable Way to Help Reduce Carbon Dioxide Levels in the Atmosphere?
380 Fertilizing the Ocean with Iron Is this a viable way to help reduce carbon dioxide levels in the atmosphere? 360 ive me half a tanker of iron, and I’ll give you an ice Twenty years on, Martin’s line is still viewed alternately age” may rank as the catchiest line ever uttered by a as a boast or a quip—an opportunity too good to pass up or a biogeochemist.“G The man responsible was the late John Martin, misguided remedy doomed to backfire. Yet over the same pe- former director of the Moss Landing Marine Laboratory, who riod, unrelenting increases in carbon emissions and mount- discovered that sprinkling iron dust in the right ocean waters ing evidence of climate change have taken the debate beyond could trigger plankton blooms the size of a small city. In turn, academic circles and into the free market. the billions of cells produced might absorb enough heat-trap- Today, policymakers, investors, economists, environ- ping carbon dioxide to cool the Earth’s warming atmosphere. mentalists, and lawyers are taking notice of the idea. A few Never mind that Martin companies are planning new, was only half serious when larger experiments. The ab- 340 he made the remark (in his Ocean Iron Fertilization sence of clear regulations for “best Dr. Strangelove accent,” either conducting experiments he later recalled) at an infor- An argument for: Faced with the huge at sea or trading the results mal seminar at Woods Hole consequences of climate change, iron’s in “carbon offset” markets Oceanographic Institution outsized ability to put carbon into the oceans complicates the picture. -
Biological Oceanography - Legendre, Louis and Rassoulzadegan, Fereidoun
OCEANOGRAPHY – Vol.II - Biological Oceanography - Legendre, Louis and Rassoulzadegan, Fereidoun BIOLOGICAL OCEANOGRAPHY Legendre, Louis and Rassoulzadegan, Fereidoun Laboratoire d'Océanographie de Villefranche, France. Keywords: Algae, allochthonous nutrient, aphotic zone, autochthonous nutrient, Auxotrophs, bacteria, bacterioplankton, benthos, carbon dioxide, carnivory, chelator, chemoautotrophs, ciliates, coastal eutrophication, coccolithophores, convection, crustaceans, cyanobacteria, detritus, diatoms, dinoflagellates, disphotic zone, dissolved organic carbon (DOC), dissolved organic matter (DOM), ecosystem, eukaryotes, euphotic zone, eutrophic, excretion, exoenzymes, exudation, fecal pellet, femtoplankton, fish, fish lavae, flagellates, food web, foraminifers, fungi, harmful algal blooms (HABs), herbivorous food web, herbivory, heterotrophs, holoplankton, ichthyoplankton, irradiance, labile, large planktonic microphages, lysis, macroplankton, marine snow, megaplankton, meroplankton, mesoplankton, metazoan, metazooplankton, microbial food web, microbial loop, microheterotrophs, microplankton, mixotrophs, mollusks, multivorous food web, mutualism, mycoplankton, nanoplankton, nekton, net community production (NCP), neuston, new production, nutrient limitation, nutrient (macro-, micro-, inorganic, organic), oligotrophic, omnivory, osmotrophs, particulate organic carbon (POC), particulate organic matter (POM), pelagic, phagocytosis, phagotrophs, photoautotorphs, photosynthesis, phytoplankton, phytoplankton bloom, picoplankton, plankton, -
SSWIMS: Plankton
Unit Six SSWIMS/Plankton Unit VI Science Standards with Integrative Marine Science-SSWIMS On the cutting edge… This program is brought to you by SSWIMS, a thematic, interdisciplinary teacher training program based on the California State Science Content Standards. SSWIMS is provided by the University of California Los Angeles in collaboration with the Los Angeles County school districts, including the Los Angeles Unified School District. SSWIMS is funded by a major grant from the National Science Foundation. Plankton Lesson Objectives: Students will be able to do the following: • Determine a basis for plankton classification • Differentiate between various plankton groups • Compare and contrast plankton adaptations for buoyancy Key concepts: phytoplankton, zooplankton, density, diatoms, dinoflagellates, holoplankton, meroplankton Plankton Introduction “Plankton” is from a Greek word for food chains. They are autotrophs, “wanderer.” It is a making their own food, using the collective term for process of photosynthesis. The the various animal plankton or zooplankton eat organisms that drift or food for energy. These swim weakly in the heterotrophs feed on the open water of the sea or microscopic freshwater lakes and ponds. These world of the weak swimmers, carried about by sea and currents, range in size from the transfer tiniest microscopic organisms to energy up much larger animals such as the food jellyfish. pyramid to fishes, marine mammals, and humans. Plankton can be divided into two large groups: planktonic plants and Scientists are interested in studying planktonic animals. The plant plankton, because they are the basis plankton or phytoplankton are the for food webs in both marine and producers of ocean and freshwater freshwater ecosystems. -
Productivity Is Defined As the Ratio of Output to Input(S)
Institute for Development Policy and Management (IDPM) Development Economics and Public Policy Working Paper Series WP No. 31/2011 Published by: Development Economics and Public Policy Cluster, Institute of Development Policy and Management, School of Environment and Development, University of Manchester, Manchester M13 9PL, UK; email: [email protected]. PRODUCTIVITY MEASUREMENT IN INDIAN MANUFACTURING: A COMPARISON OF ALTERNATIVE METHODS Vinish Kathuria SJMSOM, Indian Institute of Technology Bombay [email protected] Rajesh S N Raj * Centre for Multi-Disciplinary Development Research, Dharwad [email protected] Kunal Sen IDPM, University of Manchester [email protected] Abstract Very few other issues in explaining economic growth has generated so much debate than the measurement of total factor productivity (TFP) growth. The concept of TFP and its measurement and interpretation have offered a fertile ground for researchers for more than half a century. This paper attempts to provide a review of different issues in the measurement of TFP including the choice of inputs and outputs. The paper then gives a brief review of different techniques used to compute TFP growth. Using three different techniques – growth accounting (non-parametric), production function accounting for endogeniety (semi-parametric) and stochastic production frontier (parametric) – the paper computes the TFP growth of Indian manufacturing for both formal and informal sectors from 1989-90 to 2005-06. The results indicate that the TFP growth of formal and informal sector has differed greatly during this 16-year period but that the estimates are sensitive to the technique used. This suggests that any inference on productivity growth in India since the economic reforms of 1991 is conditional on the method of measurement used, and that there is no unambiguous picture emerging on the direction of change in TFP growth in post-reform India. -
Structure and Distribution of Cold Seep Communities Along the Peruvian Active Margin: Relationship to Geological and Fluid Patterns
MARINE ECOLOGY PROGRESS SERIES Vol. 132: 109-125, 1996 Published February 29 Mar Ecol Prog Ser l Structure and distribution of cold seep communities along the Peruvian active margin: relationship to geological and fluid patterns 'Laboratoire Ecologie Abyssale, DROIEP, IFREMER Centre de Brest, BP 70, F-29280 Plouzane, France '~epartementdes Sciences de la Terre, UBO, 6 ave. Le Gorgeu, F-29287 Brest cedex, France 3~aboratoireEnvironnements Sedimentaires, DROIGM, IFREMER Centre de Brest, BP 70, F-29280 Plouzane, France "niversite P. et M. Curie, Observatoire Oceanologique de Banyuls, F-66650 Banyuls-sur-Mer, France ABSTRACT Exploration of the northern Peruvian subduction zone with the French submersible 'Nau- tile' has revealed benthlc communities dominated by new species of vesicomyid bivalves (Calyptogena spp and Ves~comyasp ) sustained by methane-nch fluid expulsion all along the continental margin, between depths of 5140 and 2630 m Videoscoplc studies of 25 dives ('Nautiperc cruise 1991) allowed us to describe the distribution of these biological conlnlunities at different spahal scales At large scale the communities are associated with fluid expuls~onalong the major tectonic features (scarps, canyons) of the margln At a smaller scale on the scarps, the distribuhon of the communities appears to be con- trolled by fluid expulsion along local fracturatlon features such as joints, faults and small-scale scars Elght dlves were made at one particular geological structure the Middle Slope Scarp (the scar of a large debns avalanche) where numerous -
Ch. 9: Ocean Biogeochemistry
6/3/13 Ch. 9: Ocean Biogeochemistry NOAA photo gallery Overview • The Big Picture • Ocean Circulation • Seawater Composition • Marine NPP • Particle Flux: The Biological Pump • Carbon Cycling • Nutrient Cycling • Time Pemitting: Hydrothermal venting, Sulfur cycling, Sedimentary record, El Niño • Putting It All Together Slides borrowed from Aradhna Tripati 1 6/3/13 Ocean Circulation • Upper Ocean is wind-driven and well mixed • Surface Currents deflected towards the poles by land. • Coriolis force deflects currents away from the wind, forming mid-ocean gyres • Circulation moves heat poleward • River influx is to surface ocean • Atmospheric equilibrium is with surface ocean • Primary productivity is in the surface ocean Surface Currents 2 6/3/13 Deep Ocean Circulation • Deep and Surface Oceans separated by density gradient caused by differences in Temperature and Salinity • This drives thermohaline deep circulation: * Ice forms in the N. Atlantic and Southern Ocean, leaving behind cold, saline water which sinks * Oldest water is in N. Pacific * Distribution of dissolved gases and nutrients: N, P, CO2 Seawater Composition • Salinity is defined as grams of salt/kg seawater, or parts per thousand: %o • Major ions are in approximately constant concentrations everywhere in the oceans • Salts enter in river water, and are removed by porewater burial, sea spray and evaporites (Na, Cl). • Calcium and Sulfate are removed in biogenic sediments • Magnesium is consumed in hydrothermal vents, in ionic exchange for Ca in rock. • Potassium adsorbs in clays. 3 6/3/13 Major Ions in Seawater The Two-Box Model of the Ocean Precipitation Evaporation River Flow Upwelling Downwelling Particle Flux Sedimentation 4 6/3/13 Residence time vs. -
Plankton Biomass and Food Web Structure
Plankton Biomass and Food Web Structure Matthew Church OCN 621 Spring 2009 Food Web Structure is Central to Elemental Cycling “Microsystems” In every liter of seawater there are all the organisms for a complete, functional ecosystem. These organisms form the fabric of life in the sea - the other organisms are embroidery on this fabric. Important things to know about ocean ecosystems • Population size and biomass (biogenic carbon): provides information on energy available to support the food web • Growth, production, metabolism: turnover of material through the food web and insight into physiology. • Controls on growth and population size In a “typical” liter of seawater… •Fish None • Zooplankton 10 • Diatoms 1,000 • Dinoflagellates 10,000 • Nanoflagellates 1,000,000 • Cyanobacteria 100,000,000 • Prokaryotes 1,000,000,000 • Viruses 10,000,000,000 High abundance does not necessarily equate to high biomass. Size is important. 1011 1010 Viruses 109 Bacteria 108 Cyanobacteria 107 106 Protists 105 104 103 102 101 Phytoplankton 100 Abudance (number per liter)Abudance 10-1 Zooplankton 10-2 0.01 0.1 1 10 100 1000 Size (µm) Why are pelagic organisms so small? Consider a spherical cell: SA = 3.1 µm2 SA= 4πr2 r = 0.50 µm V = 0.52 µm3 SA : V = 15.7 V= 4/3 πr3 SA = 12.6 µm2 r = 1.0 V = 4.2 µm3 SA : V = 3.0 The smaller the cell, the larger the SA:V Greater SA:V increases their ability to absorb nutrients from a dilute solution. This may allow smaller cells to out compete larger cells for limiting nutrients.