DOCSLIB.ORG

Bloom of Trichodesmium Erythraeum (Ehr.) and Its Impact on Water Quality and Plankton Community Structure in the Coastal Waters of Southeast Coast of India

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Bloom of Trichodesmium Erythraeum (Ehr.) and Its Impact on Water Quality and Plankton Community Structure in the Coastal Waters of Southeast Coast of India Indian Journal of Marine Science Vol. 39(3), September 2010, pp. 323-333 Bloom of Trichodesmium erythraeum (Ehr.) and its impact on water quality and plankton community structure in the coastal waters of southeast coast of India A K Mohanty 1, K K Satpathy 1, G Sahu 1, K J Hussain 1, M V R Prasad 1 & S K Sarkar 2 1 Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu- 603 102 India 2 Department of Marine Science, University of Calcutta, Kolkata- 700 019 India [Email : satpathy@igcar.gov.in] Received 14 September 2009; revised 11 January 2010 An intense bloom of Trichodesmium erythraeum was observed in the coastal waters (about 600 m away from the shore) of southeast coast of India during the post-northeast monsoon period. The bloom appeared during a relatively high temperature condition with coastal water salinity > 31 psu. A significant reduction in nitrate concentration was noticed during the bloom period, whereas, relatively high concentration of phosphate and total phosphorous was observed. An abrupt increase in ammonia concentration to the tune of 284.36 µmol l -1 was observed which coincided with the highest Trichodesmium density (2.88 × 10 7 cells l -1). Contribution of Trichodesmium to the total phytoplankton density ranged from 7.79% to 97.01%. A distinct variation in phytoplankton species number and phytoplankton diversity indices was noticed. The lowest diversity indices coincided with the observed highest Trichodesmium density. Concentrations of chlorophyll-a (maximum 42.15 mg m -3) and phaeophytin (maximum 46.23 mg m -3) increased abnormally during the bloom. [Key words : bloom, phytoplankton, tropical, Trichodesmium, oligotrophic, cyanobacteria] Introduction (> 30 km). This appears to be the second report of Trichodesmium erythraeum, a marine Trichodesmium bloom which was sighted near the cyanobacterium, is an important nitrogen-fixer in the coast similar to the last year report from the same sea. It is one of the common bloom-forming species locality 15 . found in tropical and sub-tropical waters, particularly During a regular coastal water monitoring program, in the eastern tropical Pacific and Arabian Sea, a prominent discoloration of the surface water was contributing > 30% of algal blooms of the world 1. noticed in the coastal waters of Kalpakkam (12 o 33' N Estimated global nitrogen fixation by Trichodesmium Lat. and 80 o 11' E Long) (Figure 1) on 19 th February bloom (~ 42 Tg N yr -1) and during non-bloom 2008. The bloom was very dense and created conditions (~ 20 Tg N yr -1) suggests that it is likely to yellowish-green coloured streaks (Figure 2a) of about be the dominant organism in the global ocean 4 to 5m width and 10-20m long patches. The entire nitrogen budget 1, 2 . Trichodesmium normally occurs in bloom extended to several kilometers along the coast. macroscopic bundles or colonies and blooms formed The phytoplankton responsible for discolouration was by it are often extremely patchy. The patchy spatial identified as Trichodesmium erythraeum (Figure 2b). distribution of plankton blooms is usually connected Though, bloom of Noctiluca scintillans 16 , Asterionella to the physical variability of the water body 3. glacialis 17 and Trichodesmium erythraeum 15 in the Reports in literature showed frequent occurrence of coastal waters of the Kalpakkam have been reported, Trichodesmium blooms in Indian waters, however, it the present one has many interesting features. has been reported more frequently in the west Although, the data collected during our regular work coast 4, 5, 6-11 as compared to east coast 12, 13-15 . Equipped were not concerned directly with an investigation into with buoyancy regulating gas vesicles and nitrogen the causes of the bloom, the interest stimulated from fixation enzymes, Trichodesmium is regarded as an the studies of various physicochemical and biological organism well adapted to stratified, oligotrophic characteristics of the coastal water justifies the conditions 2. All the available reports on purpose of this paper. The acumen in investigating Trichodesmium bloom from east and west coast of Trichodesmium bloom appearance and distribution India have been observed far away from the coast stems from the recent report about its harmful nature, 324 INDIAN J. MAR. SCI., VOL. 39, No, 3, SEPTEMBER 2010 Fig. 1 Study area showing the sampling location Fig. 2a & b Discolouration of coastal water of Kalpakkam by Trichodesmium erythraeum bloom patches (a); magnif ied view of bundles formed by trichome (b) sometimes causing damages to coastal fish and shellfish connotations. The impact of bloom on coastal water fauna 18 . Thus, studying the causes that favour the quality and phytoplankton community is reported in this appearance of this bloom has social and economical paper along with the characteristic feature of the bloom. MOHANTY et al .: BLOOM OF TRICHODESMIUM ERYTHRAEUM (Ehr..) AND ITS IMPACT ON WATER QUALITY 325 Materials and Methods Results and discussions Surface water samples were collected twice daily A. Hydrography The values of pH did not show significant (between 9 to 10 AM and 4 to 5 PM during the bloom variations and ranged from 8.0-8.2 during the study period (19 th to 23 rd February), whereas, during pre- period (Figure-3a). It did not show any correlation and post-bloom periods samples were collected with bloom appearance as it remained almost stable weekly only in the morning hours. Samples were during pre-bloom, bloom and post-bloom periods. drawn by lowering a clean plastic bucket from the The surface water temperature during the study period Jetty of Madras Atomic Power Station (MAPS) and analyzed for various physicochemical parameters. ranged from 27.2-32.6 °C (Figure 3b). Comparatively high temperatures were noticed during the afternoon Temperature was measured by a mercury collections. A general increase in water temperate was thermometer with an accuracy of ±0.1 oC. Winkler’s noticed from January to March, which is a general method 19 was followed for the estimation of DO. phenomenon associated with air temperature in this Salinity was estimated by Knudsen’s method 19 . pH locality during this period of the year. Most of the was measured by a pH meter (CyberScan PCD 5500) marine cyanobacteria exhibit substantial growth in the with an accuracy of ±0.1. Dissolved nutrients such as, temperature ranges 25-35 °C11. The present bloom was nitrite, nitrate, ammonia, silicate and phosphate along noticed during relatively high temperature conditions with total nitrogen (TN) and total phosphorous (TP) were estimated following the methods of Grasshoff (28.4-28.7°C in the morning and 31.2-32.6°C in the et al .19 and Parsons et al .20 . Chlorophyll-a and afternoon). Temperature has long been recognized as Trichodesmium phaeophytin were measured spectrophotometrically an important factor that controls abundance 26-27 . Generally bloom of this filamentous (Parsons et al ., 1984. The phytoplankton density was 13 estimated using Utermohl’s sedimentation technique 21 alga occurred during hot weather season , as and counted using Sedgwick Rafter counting chamber cyanobacteria require relatively high temperature for with the aid of binocular research microscope (Nikon its optimum growth compared to other phytoplankton 28-29 . The present study agreed well with Eclipse-50 i). The identification of phytoplankton 4, 13-15, 30 was done by following standard taxonomic earlier reports , which showed similar monographs such as Desikachary 22 for diatoms; temperature conditions with the appearance of 23,24 25 Trichodesmium bloom during early summer and Subramanian for dinoflagellates and Fristch 31 for green and blue-green algae (Cyanobacteria). spring in the coastal waters of India. As observed, Three diversity indices such as species richness (R), the bloom was more predominant during afternoon species diversity (D) and evenness (J) were computed period when the temperature was relatively high as compared to morning period. to evaluate the variation between phytoplankton community structure and diversity, using standard The observed salinity ranged from 31.58-33.18 psu. formulae of Gleason (1922), Shannon-Weaver (1963) A gradual increase in salinity was noticed during the and Pielou (1966) respectively. study period (Figure 3b). Stable salinity condition close to typical value of 32 psu and above is known to Fig. 3a 326 INDIAN J. MAR. SCI., VOL. 39, No, 3, SEPTEMBER 2010 support the growth and abundance of Trichodesmium . near bloom area is common to post-bloom era and It is well known that the cyanobacterium is a indicative of decayed phase of the bloom. stenohaline form with optimum growth at > 33 psu and can’t survive in low salinities 11-14 . DO B. Nutrients concentration ranged from 6.2-8.1 mg l -1 Nitrate concentrations ranged from 0.17–6.79 (Figure 3a). The lowest and the highest DO µmol l -1, the highest value being observed during the concentration was observed during the post-bloom pre-bloom period and the lowest during the bloom and bloom period respectively. Marginally high DO (Figure 3c). Relatively low nitrate levels, continuous was noticed during the bloom compared to the pre- patches with yellowish green colour and increased and post-bloom period. However, concentrations of primary production (as reflected in chlorophyll-a DO during pre-bloom period were relatively high as values) coinciding with peak bloom period compared to post-bloom period. This could be due to sufficiently indicated that the bloom was in growth photosynthetic release of oxygen by the dense algal phase. A significant reduction in nitrate concentration biomass. Similar increase of DO content during was noticed during the bloom as compared to pre- and Trichodesmium bloom has also been reported post-bloom periods. Similar reduction of nitrate earlier 2,15 . As expected relatively low DO contents concentration during Trichodesmium bloom has also were observed during the post-peak bloom period, been reported by others 12,14-15 .
Load more

Recommended publications
  • Nitrogen Fixation by Trichodesmium Spp.: an Important Source of New Nitrogen to the Tropical and Subtropical North Atlantic Ocean Douglas G
    GLOBAL BIOGEOCHEMICAL CYCLES, VOL. 19, GB2024, doi:10.1029/2004GB002331, 2005 Nitrogen fixation by Trichodesmium spp.: An important source of new nitrogen to the tropical and subtropical North Atlantic Ocean Douglas G. Capone,1 James A. Burns,1,2 Joseph P. Montoya,3 Ajit Subramaniam,4 Claire Mahaffey,1,5 Troy Gunderson,1 Anthony F. Michaels,1 and Edward J. Carpenter6 Received 6 July 2004; revised 19 January 2005; accepted 9 March 2005; published 8 June 2005. [1] The broad distribution and often high densities of the cyanobacterium Trichodesmium spp. in oligotrophic waters imply a substantial role for this one taxon in the oceanic N cycle of the marine tropics and subtropics. New results from 154 stations on six research cruises in the North Atlantic Ocean show depth-integrated N2 fixation by Trichodesmium spp. at many stations that equalled or exceeded the estimated vertical flux À of NO3 into the euphotic zone by diapycnal mixing. Areal rates are consistent with those derived from several indirect geochemical analyses. Direct measurements of N2 fixation rates by Trichodesmium are also congruent with upper water column N budgets derived from parallel determinations of stable isotope distributions, clearly showing that N2 fixation by Trichodesmium is a major source of new nitrogen in the tropical North Atlantic. We project a conservative estimate of the annual input of new N into the tropical 12 North Atlantic of at least 1.6 Â 10 mol N by Trichodesmium N2 fixation alone. This input can account for a substantial fraction of the N2 fixation in the North Atlantic inferred by several of the geochemical approaches.
    [Show full text]
  • Causative Analysis on a Nearshore Bloom of Oscillatoria Erythraea (Trichodesmium) in the Northern Gulf of Mexico
    Gulf of Mexico Science Volume 5 Number 1 Number 1 Article 1 10-1981 Causative Analysis on a Nearshore Bloom of Oscillatoria erythraea (trichodesmium) in the Northern Gulf of Mexico Lionel Eleuterius Gulf Coast Research Laboratory Harriet Perry Gulf Coast Research Laboratory Charles Eleuterius Gulf Coast Research Laboratory James Warren Gulf Coast Research Laboratory John Caldwell Gulf Coast Research Laboratory Follow this and additional works at: https://aquila.usm.edu/goms DOI: 10.18785/negs.0501.01 Recommended Citation Eleuterius, L., H. Perry, C. Eleuterius, J. Warren and J. Caldwell. 1981. Causative Analysis on a Nearshore Bloom of Oscillatoria erythraea (trichodesmium) in the Northern Gulf of Mexico. Northeast Gulf Science 5 (1). Retrieved from https://aquila.usm.edu/goms/vol5/iss1/1 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf of Mexico Science by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell@usm.edu. Eleuterius et al.: Causative Analysis on a Nearshore Bloom of Oscillatoria erythraea Northeast Gulf Science Vol5, No.1, p. 1-11 October 1981 CAUSATIVE ANALYSIS ON A NEARSHORE BLOOM OF Oscillator/a erythraea (TRICHODESMIUM) IN THE NORTHERN GULF OF MEXICO Lionel Eleuterius, Harriet Perry, Charles Eleuterius James Warren, and John Caldwell Gulf Coast Research Laboratory Ocean Springs, MS 39564 ABSTRACT: Physical, chemical, and biological characteristics which preceded and caused a bloom of Osclllatorla erythraea commonly known as trlchodesmlum In coastal waters of Mississippi and adjacent waters of the Gulf of Mexico are described.
    [Show full text]
  • Akashiwo Sanguinea
    Ocean ORIGINAL ARTICLE and Coastal http://doi.org/10.1590/2675-2824069.20-004hmdja Research ISSN 2675-2824 Phytoplankton community in a tropical estuarine gradient after an exceptional harmful bloom of Akashiwo sanguinea (Dinophyceae) in the Todos os Santos Bay Helen Michelle de Jesus Affe1,2,* , Lorena Pedreira Conceição3,4 , Diogo Souza Bezerra Rocha5 , Luis Antônio de Oliveira Proença6 , José Marcos de Castro Nunes3,4 1 Universidade do Estado do Rio de Janeiro - Faculdade de Oceanografia (Bloco E - 900, Pavilhão João Lyra Filho, 4º andar, sala 4018, R. São Francisco Xavier, 524 - Maracanã - 20550-000 - Rio de Janeiro - RJ - Brazil) 2 Instituto Nacional de Pesquisas Espaciais/INPE - Rede Clima - Sub-rede Oceanos (Av. dos Astronautas, 1758. Jd. da Granja -12227-010 - São José dos Campos - SP - Brazil) 3 Universidade Estadual de Feira de Santana - Departamento de Ciências Biológicas - Programa de Pós-graduação em Botânica (Av. Transnordestina s/n - Novo Horizonte - 44036-900 - Feira de Santana - BA - Brazil) 4 Universidade Federal da Bahia - Instituto de Biologia - Laboratório de Algas Marinhas (Rua Barão de Jeremoabo, 668 - Campus de Ondina 40170-115 - Salvador - BA - Brazil) 5 Instituto Internacional para Sustentabilidade - (Estr. Dona Castorina, 124 - Jardim Botânico - 22460-320 - Rio de Janeiro - RJ - Brazil) 6 Instituto Federal de Santa Catarina (Av. Ver. Abrahão João Francisco, 3899 - Ressacada, Itajaí - 88307-303 - SC - Brazil) * Corresponding author: helenmaffe@gmail.com ABSTRAct The objective of this study was to evaluate variations in the composition and abundance of the phytoplankton community after an exceptional harmful bloom of Akashiwo sanguinea that occurred in Todos os Santos Bay (BTS) in early March, 2007.
    [Show full text]
  • Detection and Study of Blooms of Trichodesmium Erythraeum and Noctiluca Miliaris in NE Arabian Sea S
    Detection and study of blooms of Trichodesmium erythraeum and Noctiluca miliaris in NE Arabian Sea S. G. Prabhu Matondkar 1*, R.M. Dwivedi 2, J. I. Goes 3, H.do.R. Gomes 3, S.G. Parab 1and S.M.Pednekar 1 1National Institute of Oceanography, Dona-Paula 403 004, Goa, INDIA 2Space Application Centre, Ahmedabad, Gujarat, INDIA 3Bigelow Laboratory for Ocean Sciences, West Boothbay Harbor, Maine, 04575, USA Abstract The Arabian Sea is subject to semi-annual wind reversals associated with the monsoon cycle that result in two periods of elevated phytoplankton productivity, one during the northeast (NE) monsoon (November-February) and the other during the southwest (SW) monsoon (June- September). Although the seasonality of phytoplankton biomass in these offshore waters is well known, the abundance and composition of phytoplankton associated with this distinct seasonal cycle is poorly understood. Monthly samples were collected from the NE Arabian Sea (offshore) from November to May. Phytoplankton were studied microscopically up to the species level. Phytoplankton counts are supported by Chl a estimations and chemotaxonomic studies using HPLC. Surface phytoplankton cell counts varied from 0.1912 (Mar) to 15.83 cell x104L-1 (Nov). In Nov Trichodesmium thiebautii was the dominant species. It was replaced by diatom and dinoflagellates in the following month. Increased cell counts during Jan were predominantly due to dinoflagellates Gymnodinium breve , Gonyaulax schilleri and Amphidinium carteare . Large blooms of Noctiluca miliaris were observed in Feb a direct consequence of the large populations of G. schilleri upon which N. miliaris is known to graze. In Mar and April, N. miliaris was replaced by blooms of Trichodesmium erythraeum .
    [Show full text]
  • Periodic and Coordinated Gene Expression Between a Diazotroph and Its Diatom Host
    The ISME Journal (2019) 13:118–131 https://doi.org/10.1038/s41396-018-0262-2 ARTICLE Periodic and coordinated gene expression between a diazotroph and its diatom host 1 1,2 1 3 4 Matthew J. Harke ● Kyle R. Frischkorn ● Sheean T. Haley ● Frank O. Aylward ● Jonathan P. Zehr ● Sonya T. Dyhrman1,2 Received: 11 April 2018 / Revised: 28 June 2018 / Accepted: 28 July 2018 / Published online: 16 August 2018 © International Society for Microbial Ecology 2018 Abstract In the surface ocean, light fuels photosynthetic carbon fixation of phytoplankton, playing a critical role in ecosystem processes including carbon export to the deep sea. In oligotrophic oceans, diatom–diazotroph associations (DDAs) play a keystone role in ecosystem function because diazotrophs can provide otherwise scarce biologically available nitrogen to the diatom host, fueling growth and subsequent carbon sequestration. Despite their importance, relatively little is known about the nature of these associations in situ. Here we used metatranscriptomic sequencing of surface samples from the North Pacific Subtropical Gyre (NPSG) to reconstruct patterns of gene expression for the diazotrophic symbiont Richelia and we – 1234567890();,: 1234567890();,: examined how these patterns were integrated with those of the diatom host over day night transitions. Richelia exhibited significant diel signals for genes related to photosynthesis, N2 fixation, and resource acquisition, among other processes. N2 fixation genes were significantly co-expressed with host nitrogen uptake and metabolism, as well as potential genes involved in carbon transport, which may underpin the exchange of nitrogen and carbon within this association. Patterns of expression suggested cell division was integrated between the host and symbiont across the diel cycle.
    [Show full text]
  • UNIVERSITY of CALIFORNIA, SAN DIEGO Indicators of Iron
    UNIVERSITY OF CALIFORNIA, SAN DIEGO Indicators of Iron Metabolism in Marine Microbial Genomes and Ecosystems A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Oceanography by Shane Lahman Hogle Committee in charge: Katherine Barbeau, Chair Eric Allen Bianca Brahamsha Christopher Dupont Brian Palenik Kit Pogliano 2016 Copyright Shane Lahman Hogle, 2016 All rights reserved . The Dissertation of Shane Lahman Hogle is approved, and it is acceptable in quality and form for publication on microfilm and electronically: Chair University of California, San Diego 2016 iii DEDICATION Mom, Dad, Joel, and Marie thank you for everything iv TABLE OF CONTENTS Signature Page ................................................................................................................... iii Dedication .......................................................................................................................... iv Table of Contents .................................................................................................................v List of Figures ................................................................................................................... vii List of Tables ..................................................................................................................... ix Acknowledgements ..............................................................................................................x Vita ..................................................................................................................................
    [Show full text]
  • A Model for the Marine Cyanobacteria, Trichodesmium Robson
    20th International Congress on Modelling and Simulation, Adelaide, Australia, 1–6 December 2013 www.mssanz.org.au/modsim2013 A physiological model for the marine cyanobacteria, Trichodesmium Barbara J. Robson1, Mark Baird2 and Karen Wild-Allen2 1CSIRO Land and Water, Black Mountain 2CSIRO Marine and Atmospheric Research, Hobart Email: barbara.robson@csiro.au Abstract: Nitrogen fixation by the marine cyanobacterium, Trichodesmium, is believed to form a substantial component of the nitrogen budget of the Great Barrier Reef Lagoon. Here, we present a new, physiologically-based model to predict the distribution and growth of Trichodesmium. The model has been incorporated into a large-scale, process-based, three-dimensional hydrodynamic, sediment dynamic and biogeochemical model of the Great Barrier Reef Lagoon through eReefs, a major collaborative project that is developing near-real-time and forecasting models to inform management of this important environmental asset. The model simulates the growth and respiration of Trichodesmium colonies, along with uptake of nutrients, fixation of atmospheric nitrogen, changes in cellular buoyancy, grazing by zooplankton and death associated with lysis by cyanophages. To facilitate improved simulation of nutrient dynamics as well as changes in carbohydrate ballasting (which affects buoyancy), the model allows variable intracellular C:N:P:Chlorophyll a ratios. Chlorophyll a accumulation and Trichodesmium growth depend on the intracellular availability of nutrients and fixed carbon. Carbon accumulation is a function of the spectrally resolved light environment, so that changes in light quality as well as light intensity may affect growth. As Trichodesmium colonies accumulate carbon, their buoyancy decreases, allowing the vertical movement of Trichodesmium through the water column to be simulated.
    [Show full text]
  • Trichodesmium Spp., the Gldglu Ratio Closely Approximated the Glnlakg Ratio Over the Die1 Cycle
    MARINE ECOLOGY PROGRESS SERIES Published November 3 Mar Ecol Prog Ser Nitrogen fixation, uptake and metabolism in natural and cultured populations of Trichodesmium spp. Margaret R. Mulholland*, Douglas G. Capone*" Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, PO Box 38. Solomons, Maryland 20688, USA ABSTRACT: Uptake rates of several combined N sources, NZfixation, intracellular glutamate (glu) and glutamine (gln) pools, and glutamine synthetase (GS) activity were measured in natural populations and a culture of Trichodesmium IMSlOl grown on seawater medium without added N. In cultured populations, the ratio of GS transferase/biosynthetic activity (an index of the proportion of the GS pool that is active) was lower, and intracellular pools of glu and gln and the ratios of gldglu and glnla- ketoglutarate (glnlakg) ratios were higher when NZ fixation was highest (mid-day). There was an excess capacity for NH,' assimilation via GS, indicating that this was not the rate-limiting step in N uti- lization. In natural populations of Trichodesmium spp., the gldglu ratio closely approximated the glnlakg ratio over the die1 cycle. High gln/glu and gln/akg ratios were noted in near-surface popula- tion~.These ratios decreased in samples collected from greater depths. Natural populations of Tn- chodesmium spp. showed a high capacity for the uptake of NH4+,glu, and mixed amino acids (AA). Rates of NO3- and urea uptake were low. NH,+ accumulated in the culture medium during growth and rates of NH4+ uptake showed a positive relationship with the NH4+ concentration in the medium. Although rates of NZfixation were highest and accounted for the majority of the total measured N uti- lization during mid-day, rates of NH4+uptake exceeded rates of NZfixation throughout much of the die1 cycle.
    [Show full text]
  • Structure, Morphogenesis of Calyptra and Nomenclatural Identity of Trichodesmium Erythraeum Ehr
    Bangladesh J. Plant Taxon. 27(2): 273-282, 2020 (December) © 2020 Bangladesh Association of Plant Taxonomists STRUCTURE, MORPHOGENESIS OF CALYPTRA AND NOMENCLATURAL IDENTITY OF TRICHODESMIUM ERYTHRAEUM EHR. (CYANOBACTERIA) NEWLY RECORDED OFF THE SOUTH-WEST COAST OF BANGLADESH ABDUL AZIZ*AND MAHIN MOHID Department of Botany, University of Dhaka, Dhaka 1000, Bangladesh Keywords: Trichodesmium erythraeum Ehr., Microcoleaceae, Calyptra morphogenesis, Cyanobacteria, Bangladesh Abstract Trichodesmium erythraeum Ehrenberg 1830 (Cyanobacteria) has been described and newly recorded from three km off the west coast of the St. Martin’s Island (SMI), Cox’s Bazar, Bangladesh. The Red Sea algal bloom was narrowly elliptical raft-like loose aggregates 20-40 cm long, 4-8 cm wide and 2-3 cm thick. Volume of small and large Sea sawdust were 160×10-6 to 960×10-6 m3 consisting of 25-153 millions flat tuft or spindle- like colonies measured 830-1500 µm long and 155-260 µm wide with 13-16 filaments laterally in the median region. Sheath was present around each trichome even covering the tip cell wall the feature has so far not been reported for the Trichodesmium spp. Because of most likely sticky nature of the sheath 300-600 µm long filaments of 195-450 formed compact colonies without colonial sheath around. In interior filaments cells were rectangular 7-10 µm long and 6.3-10 µm wide with abundant gas vacuoles, bluish-green red, no diazocyte developed and without calyptra. Cells of peripheral filaments were without gas vacuoles, cytoplasm disorganized, appearing necrotic with glycogen granules, and produced convex to sickle-shaped four-layered calyptra consisting of outermost sheath followed by outer extra thick wall, tip cell wall and inner extra thick wall on the tip cell.
    [Show full text]
  • Great Barrier Reef Lagoon: Status Report 1, 1993-1995
    RESEARCH PUBLICATION No. 55 long-term Chlorophyll Monitoring in the Great Barrier Reef lagoon: Status Report 1, 1993-1995 ADL Steven, F Pantus, D Brooks Great Barrier Reef Marine Park Authority L Trott Australian Institute of Marine Science A REPORT TO THE GREAT BAR-IUER REEF MARINE PARK AUTHORITY © Great Barrier Reef Marine Park Authority 1998 lSSN 1037-1508 ISBN 0 642 23056 0 Published October 1998 by the Great Barrier Reef Marine ParkAuthority The opinions expressed in this docwnent are not necesarily those of the Great Barrier Reef Marine Park Authority. National Library of Australia CataIoguing-in-Publication data: Long-term chlorophyll monitoring in the Great Barrier Reef Lagoon: status report 1,199:>-1995. Bibliography. ISBN 0 642 23056 O. L Chlorophyll - Queensland. Great Barrier Reef - Analysis. 2. Water - Sampling - Queensland - Great Barrier Reef. 3. Environmental monitoring - Queensland - Great Barrier Reef. I. Steven, A. D. L. (Andrew David Leslie), 1962-. II. Great Barrier Reef Marine Park Authority (Australia). (Series: Research publication (Great Barrier Reef Marine Park Authority (Australia» ; no. 55). 363.73940943 GREAT BARRIER REEF MARINE PARI< Atri'HORITY PO 80x 1379 Townsville QId 4810 Telephone (07) 4750 0700 CONTENTS SUMMARY 1 1. INTRODUCTION " , ", 3 1.1 PrograIll Overview 3 1.2 Report Scope 3 PART ONE: DESIGN CRITERIA AND SAMPLING PROTOCOLS FOR THE GREAT BARRIER REEF NUTRIENT STATUS MONITORING NETWORK 5 2. NETWORK DEFlNITION 7 2.1 Rationale: Is the Great Barrier Reef at Risk? __ 7 2.1.1 ResponSibilities. agreements
    [Show full text]
  • Regulation of Nitrogen Metabolism in the Marine Diazotroph
    Environmental Microbiology (2010) doi:10.1111/j.1462-2920.2010.02195.x Regulation of nitrogen metabolism in the marine diazotroph Trichodesmium IMS101 under varying View metadata, citation and similar papers at core.ac.uk brought to you by CORE temperatures and atmospheric CO2 concentrationsemi_2195 1..14 provided by OceanRep Orly Levitan,1 Christopher M. Brown,2† enable Trichodesmium grown at elevated tempera- 3 2 Stefanie Sudhaus, Douglas Campbell, tures and pCO2 to extend its niche in the future ocean, Julie LaRoche3 and Ilana Berman-Frank1* through both tolerance of a broader temperature 1The Mina and Everard Goodman Faculty of Life range and higher P plasticity. Sciences, Bar Ilan University, Ramat Gan, 52900, Israel. 2Department of Biology, Mount Allison University, Introduction Sackville, NB E4L 1G7, Canada. 3IFM-GEOMAR, Leibniz Institute of Marine Sciences at Key phytoplankton species contributing to oceanic Kiel University, 24105 Kiel, Germany. primary production and global biogeochemical nutrient cycles may be significantly affected by oceanic acidifi- cation and the global increases in temperatures and Summary atmospheric pCO2. One such species is the marine We examined the influence of forecasted changes in nitrogen-fixing (diazotroph) cyanobacterium Trichodes- global temperatures and pCO2 on N2 fixation and mium spp. contributing 25–50% of the geochemically assimilation in the ecologically important cyano- derived rates of N2 fixation in various ocean basins, bacterium Trichodesmium spp. Changes of mRNA especially in the oligotrophic tropical and subtropical transcripts (nifH, glnA, hetR, psbA, psaB), protein oceans (Capone and Subramaniam, 2005; Mahaffey (nitrogenase, glutamine synthetase) pools and enzy- et al., 2005). Trichodesmium forms extensive surface matic activity (nitrogenase) were measured under blooms that stimulate the biogeochemical cycling of varying pCO2 and temperatures.
    [Show full text]
  • ORIGIN and FATE of ODOROUS METABOLITES, 2-METHYLISOBORNEOL and GEOSMIN, in a EUTROPHIC RESERVOIR Nicolas André Clercin Submit
    ORIGIN AND FATE OF ODOROUS METABOLITES, 2-METHYLISOBORNEOL AND GEOSMIN, IN A EUTROPHIC RESERVOIR Nicolas André Clercin Submitted to the faculty of the University Graduate School in partial fulfillment of the requirements for the degree Doctor of Philosophy in the Department of Earth Sciences, Indiana University June 2019 Accepted by the Graduate Faculty of Indiana University, in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Doctoral Committee ______________________________________ Gregory K. Druschel, PhD, Chair ______________________________________ Pierre-André Jacinthe, PhD November 13, 2018 ______________________________________ Gabriel Filippelli, PhD ______________________________________ Max Jacobo Moreno-Madriñán, PhD ______________________________________ Sarath Chandra Janga, PhD ii © 2019 Nicolas André Clercin iii DEDICATION I would like to dedicate this work to my family, my wife Angélique and our three sons Pierre-Adrien, Aurélien and Marceau. I am aware that the writing of this manuscript has been an intrusion into our daily life and its achievement now closes the decade-long ‘Indiana’ chapter of our family. Another dedication to my parents and my young brother who have always been supportive and respectful of my choices even if they never fully understood the content of my research. A special thought to my dad (†2005) who loved so much sciences and technologies but never got the chance to study as a kid. Him who idolized his own father, a WWII resistant but became head of the family upon his father’s death when he was only 8. Him who had to work to support his widowed mother and his two younger brothers. Him who decided to join the French navy at the age of 16 as a seaman recruit in order to finally reach his personal goal and study, learn diesel engine mechanics, a skill that served him later in the civilian life.
    [Show full text]