Chapter 1: General Introduction

Total Page:16

File Type:pdf, Size:1020Kb

Chapter 1: General Introduction ii Table of Contents ................................................................................................................. ii List of Figure ....................................................................................................................... iv List of Tables ....................................................................................................................... vi Acknowledgements.............................................................................................................. ix Summary ........................................................................................................................... xi Chapter 1: General Introduction........................................................................................ 1 1.1 Estuaries as systems…………………………………………………………………………………..1 1.2 Literature review as background to this study……………………………………………………….4 1.2.1 Soft-sediment fauna...................................................................................................................4 1.2.1.1 Salinity & Hydrology .............................................................................................................5 1.2.1.2 Sediment particle size.............................................................................................................8 1.2.1.3 Larval settlement and recruitment ..........................................................................................9 1.2.2 Bivalve molluscs as study organisms .....................................................................................10 1.3 Hypotheses, Objectives & Aims of this study………………………………………………………..12 Chapter 2: Study Area & General Methodology ............................................................ 17 2.1 The Hopkins River…………………………………………………………………………………...17 2.2 The Hopkins River estuary…………………………………………………………………………..17 2.3 Study sites……………………………………………………………………………………………19 2.4 The study organism - Soletellina alba (Bivalvia: Psammobiidae)…………………………………24 2.5 General Methodology……………………………………………………………………………….26 2.5.1 Abundance estimates...............................................................................................................26 2.5.2 Measurements of length & mass ............................................................................................27 2.5.3 Monitoring of growth..............................................................................................................28 2.6 Data Analyses………………………………………………………………………………………..28 Chapter 3: Hydrology, river discharge & the physico-chemical environment ............ 63 3.1 Introduction………………………………………………………………………………………….63 3.2 Methods………………………………………………………………………………………………64 3.2.1 Hydrology & river discharge..................................................................................................64 3.2.2 Salinity......................................................................................................................................64 3.2.3 Dissolved oxygen......................................................................................................................67 3.2.4 Statistical Analysis...................................................................................................................68 3.2.4.1 River discharge......................................................................................................................68 3.2.4.2 Salinity ..................................................................................................................................68 3.3 Results………………………………………………………………………………………………..68 3.3.1 Hydrology & river discharge..................................................................................................68 3.3.2 Salinity......................................................................................................................................69 3.3.3 Dissolved oxygen......................................................................................................................72 3.4 Discussion……………………………………………………………………………………………72 Chapter 4: The population dynamics of S. alba ............................................................ 100 4.1 Introduction………………………………………………………………………………………...100 4.2 Methods……………………………………………………………………………………………..103 4.2.1 Distribution & abundance ....................................................................................................103 4.2.2 Recruitment of juveniles .......................................................................................................106 4.2.3 Data Analysis .........................................................................................................................108 4.2.3.1 Distribution & abundance ...................................................................................................108 iii 4.2.3.2 Length-frequency data.........................................................................................................109 4.2.3.3 Recruitment of juveniles......................................................................................................110 4.3 Results………………………………………………………………………………………………112 4.3.1 Distribution & abundance ....................................................................................................112 4.3.2 Length-frequency data..........................................................................................................114 4.3.3 Recruitment of juveniles .......................................................................................................115 4.4 Discussion…………………………………………………………………………………………..118 4.4.1 Abundance and distribution.................................................................................................118 4.4.2 Length-frequency data..........................................................................................................120 4.4.3 Recruitment of juveniles. ......................................................................................................122 Chapter 5: Growth........................................................................................................... 171 5.1 Introduction………………………………………………………………………………………..171 5.2 Methods…………………………………………………………………………………………….172 5.3 Data Analysis………………………………………………………………………………………176 5.4 Results………………………………………………………………………………………………178 5.4.1 Pilot cage experiments, 1996-1997 .......................................................................................178 5.4.1 Caged and uncaged bivalves, 1997-1998..............................................................................179 5.5 Discussion…………………………………………………………………………………………..181 Chapter 6: Response to fluctuations in salinity............................................................. 216 6.1 Introduction………………………………………………………………………………………...216 6.2 Methods…………………………………………………………………………………………….219 6.2.1 Abundance and condition in relation to channel elevation................................................219 6.2.2 Growth, condition & mortality of caged bivalves at two channel elevations ...................222 6.2.3 Salinity tolerance experiment...............................................................................................223 6.3 Data Analyses………………………………………………………………………………………225 6.3.1 Abundance and condition in relation to channel elevation................................................225 6.3.2 Growth, condition & mortality of caged bivalves at two channel elevations ...................225 6.3.3 Salinity tolerance experiment...............................................................................................226 6.4 Results………………………………………………………………………………………………227 6.4.1 Abundance and condition in relation to channel elevation................................................227 6.4.2 Growth, condition & mortality of caged bivalves at two channel elevations ...................229 6.4.3 Salinity tolerance experiment...............................................................................................229 6.5 Discussion…………………………………………………………………………………………..230 6.2.1 Abundance and condition in relation to channel elevation................................................230 6.3.2 Growth, condition & mortality of caged bivalves at two channel elevations ...................232 6.2.3 Salinity tolerance experiment...............................................................................................232 Chapter 7: General Discussion ....................................................................................... 266 7.1 Hydrology and physico-chemical conditions during the study period……………………………266 7.2 Understanding S. alba in terms of its size, abundance, distribution & life history - is it like other estuarine bivalves?……………………………………………………………….267 7.3 Modelling the interaction of the physico-chemical environment and the population dynamics of S. alba - future prospects………………………………………………………………………..270 7.3.1 Potential physico-chemical models.......................................................................................270 7.3.2 Physiological Models .............................................................................................................271 7.4. Peculiarities of population dynamics in estuaries that alternately flood & close - a new regional versus global perspective needed?………………………………………………...274 7.5 Returning to the initial hypotheses and aims of this study………………………………………..276
Recommended publications
  • Lake Macquarie Benthos Survey
    Lake Macquarie Benthos Survey Prepared for Great Southern Energy Pty. Ltd. (trading as Delta Coal) Chain Valley Colliery Report No. 16 By Dr John H. Laxton, Dr Emma Laxton and Ms Zofia Laxton September 2019 J.H. & E.S. Laxton - Environmental Consultants P/L 170 Warrimoo Avenue, St. Ives. NSW 2075 Australia Telephone 0447 653 387 Email [email protected] Table of Contents 1. Summary of Findings 4 2. Introduction 6 3. Location of Sampling Stations 7 4. Selection and Evaluation of the Sampling Method 7 5. Sampling Procedure 11 6. Factors Affecting the Depth of water in Lake Macquarie 12 7. Water Quality of Lake Macquarie (April 1983 – March 1997) 13 8. Light attenuation in Lake Macquarie (1983 – 1997) 15 9. Results 16 10. Benthos of Study Area – February 2012 to September 2019 16 11. Molluscs found as dead shells 23 12. Benthic organisms of the Study Area – September 2019 29 13. Sediment Analysis 40 14. Water Quality Profiles – September 2019 42 15. Analysis of data 43 16. Conclusions 48 17. References and Acknowledgements 49 2 List of Tables 1. Co-ordinates of Benthos Sampling Stations prepared by the LDO team 10 2. Water Quality of the body of Lake Macquarie (1983-1997) 14 3. Organisms found at sampling Stations on 10th and 11th March 2019 30 4. Number of species found at each station from February 2012 to September 2019 37 Mean number of marine benthic organisms for Control, Reference and Impact Stations 5. 39 (September 2019) 7. Percent mud in sediment from each station - February 2012 to September 2019 41 8.
    [Show full text]
  • Factors Influencing Fish Assemblages of Intermittently Closed and Open Lakes and Lagoons (Icolls) of the Central and Near-South Coasts of New South
    Factors influencing fish assemblages of Intermittently Closed and Open Lakes and Lagoons (ICOLLs) of the Central and Near-South Coasts of New South Wales, Australia Leslie Milton Edwards BSc, MSc Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy at The University of Newcastle, Australia August 2013 Statement of Originality The thesis contains no material which has been accepted for the award of any other degree or diploma in any university or other tertiary institution and, to the best of my knowledge and belief, contains no material previously published or written by another person, except where due reference has been made in the text. I give consent to the final version of my thesis being made available worldwide when deposited in the University’s Digital Repository, subject to the provisions of the Copyright Act 1968. Signed: ……………………………………………………… (Leslie Milton Edwards) i Acknowledgements Acknowledgements Firstly to Professor William Gladstone whose supervision and guidance was invaluable over a long, long period of time, especially during those tough and frustrating periods of explaining statistics. However you were always available and provided inspiration during the duration of this epic thesis. To Dr David Powter who provided support, ideas and fun, as well as assistance in the field. To Dr Tom Trnski you gave invaluable advice and direction as well as aid in identification of fishes during the larval fish study. The work in this thesis was undertaken over a long period of time and involved the assistance of many people both in the field and in the laboratory, without them this project would not have been possible.
    [Show full text]
  • Assessing Dependence on Groundwater of Nearshore Coastal Habitats in South-East South Australia
    Assessing dependence on groundwater of nearshore coastal habitats in south-east South Australia Rohan J Henry BSc. (Aq.Sci.) Hons A thesis submitted for the degree of Doctor of Philosophy, School of Biological Sciences, Faculty of Science and Engineering, Flinders University, Adelaide August 2011 i Table of Contents Abstract...................................................................................................... vii Declaration ................................................................................................... x Acknowledgements ..................................................................................... xi 1 Why study groundwater dependent ecosystems in nearshore coastal ecosystems? ................................................................................................. 1 1.1 INTRODUCTION .................................................................................... 1 1.2 BACKGROUND LITERATURE REVIEW ................................................... 2 1.2.1 Non-ecological studies ................................................................. 3 1.2.2 Isotopic analyses of biota and water............................................ 7 1.2.3 Ecological Studies ....................................................................... 11 1.2.4 Management-based reviews: presumed effects and importance of groundwater? ....................................................................................... 20 1.2.5 South East Regional South Australian Studies ........................... 24
    [Show full text]
  • Draft Conservation Advice for Salt-Wedge Estuaries Ecological Community
    Draft Conservation Advice for Salt-wedge Estuaries Ecological Community Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) (s266B) DRAFT FINAL (15/6/2017) <Approved> Conservation Advice (including Listing Advice) for the Assemblages of species associated with open-coast salt-wedge estuaries of western and central Victoria ecological community 1. The Threatened Species Scientific Committee (the Committee) was established under the EPBC Act and has obligations to present advice to the Minister for the Environment (the Minister) in relation to the listing and conservation of threatened ecological communities, including under sections 189, 194N and 266B of the EPBC Act. 2. If approved <The Committee provided its advice on Assemblages of species associated with open-coast salt-wedge estuaries of western and central Victoria ecological community to the Minister as a draft of this Conservation Advice in 2017. The Committee recommended that: the ecological community merits listing as <endangered> under the EPBC Act; and a recovery plan is not required for the ecological community at this time. 3. [If approved] In 2017, the Minister accepted the Committee’s advice, adopting this document as the approved Conservation Advice. The Minister amended the list of threatened ecological communities under section 184 of the EPBC Act to include Assemblages of species associated with open-coast salt-wedge estuaries of western and central Victoria ecological community in the Endangered category.> 4. A draft Conservation Advice for this ecological community was made available for expert and public comment for a minimum of 30 business days. <The Committee and Minister had regard to all public and expert comment that was relevant to the consideration of the ecological community.> 5.
    [Show full text]
  • Mangrove Clam Polymesoda Erosa (Solander 1876) in the Mangrove Ecosystem
    ECOLOGY AND POPULATION DYNAMICS OF THE MANGROVE CLAM POLYMESODA EROSA (SOLANDER 1876) IN THE MANGROVE ECOSYSTEM Thesis submitted for the degree of Doctor of Philosophy In Marine Science Goa University By Miss Sandhya Clemente M.Sc. National Institute of Oceanography Dona-Paula, Goa • F INDIA s i/o R 4'--415nder the Guidance of Dr. B.S. Ingole Scientist F Biological Oceanography Division National Institute of Oceanography Dona-Paula, Goa August 2007 CERTIFICATE This is to certify that the thesis entitled ' Ecology and Population Dynamics of the Mangrove Clam Polymesoda erosa (Solander, 1876) in the Mangrove Ecosystem' submitted by Sandhya Clemente for the award of the degree of Doctor of Philosophy in Marine Science is based on original studies carried by her under my supervision. The thesis or any part thereof has not been previously submitted for any degree or diploma in any Universities or Institutions. Place: Dona Paula r. B.S. ng i le Date: AD, .2,0 0+ Research Guide r--0-Tri-4-7-<">'■ 7 - 17 .6' N \ Scientist, /0 ,„ css s , ,National Institute of Oceanography if - ' T ----------- — -4 n 41 1 ,.. ; [i ,I . ,, I onaD Paula, Goa-403 004 i i I f - ,/, -Vet. Co- 1- g.--e-4-1_;144) e_x;72 .e/) 1-rDvo 9_7O cvvvo 'NI. 7'S kfia,i e DECLARATION As required under the University Ordinance 0.19.8 (iv), I hereby declare that the present thesis entitled 'Ecology and Population Dynamics of the Mangrove Clam Polymesoda erosa (Solander, 1876) in the Mangrove Ecosystem' is my original work carried out in the National Institute of Oceanography, Dona-Paula, Goa and the same has not been submitted in part or in full elsewhere for any other degree or diploma.
    [Show full text]
  • EIS 1078 Vol 2 ABO1 9707 Sand Extraction in Griffins
    EIS 1078 Vol 2 ABO1 9707 Sand extraction in Griffins Bay : environmental impact statement ' flfl!•IIIflIJfl•&flfl SW DEPT PR1AR INDUSTRIES AB01 9707 SOUTH COAST EQUIPMENT PTY LTD SAND EXTRACTION I IN GRIFFINS BAY VOLUME 2 I ENVIRONMENTAL IMPACT STATEMENT WORKING PAPERS SOUTH COASTEQUIPMENT PTY LTD SAND EXTRACTION IN GRIFFINS BAY VOLUME 2 ENVIRONMENTAL IMPACT STATEMENT WORKING PAPERS April 1995 GUTTERIDGE HASKINS & DAVEY PlY LTD 39 Regent Street, RAILWAY SQUARE NSW 2000 Telephone: (02) 690 7070 Facsimile: (02) 698 1780 © Gutteridge Haskins & Davey Pty Ltd 1995 This document is and shall remain the property of Gutteridge Haskins & Davey Pty Ltd. The document may only be used for the purpose for which it was commissioned and in accordance with the Terms of Engagement for the commission. Unauthorised use of this document in any form whatsoever is prohibited. 217/027419/00 R4438 lJ:LT CONTENTS Acoustical Impact Assessment Proposed Dredging of Griffins Bay, Lake illawarra, NSW James Madden Cooper Atkins Pty Ltd, 1994 Soclo-Economic Impacts of the Proposal to Extract Sand from Griffins Bay, Lake Illawarra Economic Planning Impact Consultants Pty Ltd, 1995 An Assessment of Impacts on Marine Flora, Fauna and Fisheries of a Proposal to Extract Sand from Griffins Bay, Lake Illawarra The Ecology Lab Pty Limited, 1995. Griffins Bay Sand Extraction EIS Gutteridge Haskins & Davey Pty Ltd M114182 ACOUSTICAL IMPACT ASSESSMENT PROPOSED DREDGING OF GRIFFINS BAY, LAKE ILLAWARRA NSW JAMES MADDEN COOPER ATKINS PTY LTD, 1994 Griffins Bay Sand Extraction EIS Gutteridge Haskins & Davey Pty Ud M114182 JAMES MADDEN COOPER ATKINS PlY LIMITED. CONSULTING ACOUSTICAL & VIBRATION ENGINEERS ACOUSTICAL IMPACT ASSESSMENT PROPOSED DREDGIIG OF GR1FFIT' BAY LAKE ILLAWARRA NSW 24.2467.R2:GA37 Prepared for: Gutteridge Haskins & Davey Pty Limited 39 Regent Street RAILWAY SQUARE.
    [Show full text]
  • Atlantic Mud-Piddock (Barnea Truncata)
    COSEWIC Assessment and Status Report on the Atlantic Mud-piddock Barnea truncata in Canada THREATENED 2009 COSEWIC status reports are working documents used in assigning the status of wildlife species suspected of being at risk. This report may be cited as follows: COSEWIC. 2009. COSEWIC assessment and status report on the Atlantic Mud-piddoc Barnea truncata in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vii + 42 pp. (www.sararegistry.gc.ca/status/status_e.cfm). Production note: COSEWIC would like to acknowledge Derek S. Davis and Andrew J. Hebda for writing the provisional status report on Atlantic Mud-piddock Barnea truncata, prepared under contract with Environment Canada. The contractors’ involvement with the writing of the status report ended with the acceptance of the provisional report. Any modifications to the status report during the subsequent preparation of the 6- month interim and 2-month interim status reports were overseen by Robert Forsyth, COSEWIC Molluscs Specialist Subcommittee Co-chair. For additional copies contact: COSEWIC Secretariat c/o Canadian Wildlife Service Environment Canada Ottawa, ON K1A 0H3 Tel.: 819-953-3215 Fax: 819-994-3684 E-mail: COSEWIC/[email protected] http://www.cosewic.gc.ca Également disponible en français sous le titre Ếvaluation et Rapport de situation du COSEPAC sur la pholade tronquée (Barnea truncata) au Canada. Cover illustration/photo: Atlantic Mud-piddock — Beach Shell from the Minas Basin. Photo by Christina McCorry. ©Her Majesty the Queen in Right of Canada, 2010. Catalogue No. CW69-14/594-2010E-PDF ISBN 978-1-100-15127-4 Recycled paper COSEWIC Assessment Summary Assessment Summary – November 2009 Common name Atlantic Mud-piddock Scientific name Barnea truncata Status Threatened Reason for designation This intertidal marine bivalve species is restricted to a single population in the Minas Basin, Nova Scotia.
    [Show full text]
  • (Mollusca: Bivalvia)Of Moreton Bay, Queensland
    VOLUME 54 Part 3 MEMOIRS OF THE QUEENSLAND MUSEUM BRISBANE 30 DECEMBER 2010 © Queensland Museum PO Box 3300, South Brisbane 4101, Australia Phone 06 7 3840 7555 Fax 06 7 3846 1226 Email [email protected] Website www.qm.qld.gov.au National Library of Australia card number ISSN 0079-8835 NOTE Papers published in this volume and in all previous volumes of the Memoirs of the Queensland Museum may be reproduced for scientific research, individual study or other educational purposes. Properly acknowledged quotations may be made but queries regarding the republication of any papers should be addressed to the Editor in Chief. Copies of the journal can be purchased from the Queensland Museum Shop. A Guide to Authors is displayed at the Queensland Museum web site www.qm.qld.gov.au/organisation/publications/memoirs/guidetoauthors.pdf A Queensland Government Project Typeset at the Queensland Museum A preliminary checklist of the marine bivalves (Mollusca: Bivalvia) of Moreton Bay, Queensland John M. HEALY Darryl G. POTTER Biodiversity Program, Queensland Museum, PO Box 3300 South Brisbane, QLD, 4101. Email: [email protected] Citation: Healy, J.M. & Potter, D.G. 2010 12 30. A preliminary checklist of the marine bivalves (Mollusca: Bivalvia) of Moreton Bay, Queensland. In, Davie, P.J.F. & Phillips, J.A. (Eds), Proceedings of the Thirteenth International Marine Biological Workshop, The Marine Fauna and Flora of Moreton Bay, Queensland, Memoirs of the Queensland Museum – Nature 54(3): 235-252. Brisbane. ISSN 0079-8835. ABSTRACT A preliminary checklist of the bivalve molluscs of Moreton Bay is presented, based on the holdings of the Queensland Museum, supplemented by material derived from the 2005 Moreton Bay Workshop, the Bivalve Assembling the Tree of Life expedition (2008) to Moreton Bay, and published literature.
    [Show full text]
  • Conceptual Food-Web Models for the Coorong: a Focus on Fishes and the Influence of Freshwater Inflows
    Conceptual food-web models for the Coorong: A focus on fishes and the influence of freshwater inflows G. C. Giatas and Q. Ye SARDI Publication No. F2016/000124-1 SARDI Research Report Series No. 892 SARDI Aquatics Sciences PO Box 120 Henley Beach SA 5022 June 2016 Giatas, G. and Ye, Q. (2016) Coorong food-web models Conceptual food-web models for the Coorong: A focus on fishes and the influence of freshwater inflows G. C. Giatas and Q. Ye SARDI Publication No. F2016/000124-1 SARDI Research Report Series No. 892 June 2016 I Giatas, G. and Ye, Q. (2016) Coorong food-web models This publication may be cited as: Giatas, G. C. and Ye, Q. (2016). Conceptual food-web models for the Coorong: A focus on fishes and the influence of freshwater inflows. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. F2016/000124-1. SARDI Research Report Series No. 892. 77pp. South Australian Research and Development Institute SARDI Aquatic Sciences 2 Hamra Avenue West Beach SA 5024 Telephone: (08) 8207 5400 Facsimile: (08) 8207 5406 http://www.pir.sa.gov.au/research DISCLAIMER The authors warrant that they have taken all reasonable care in producing this report. The report has been through the SARDI internal review process, and has been formally approved for release by the Research Chief, Aquatic Sciences. Although all reasonable efforts have been made to ensure quality, SARDI does not warrant that the information in this report is free from errors or omissions. SARDI does not accept any liability for the contents of this report or for any consequences arising from its use or any reliance placed upon it.
    [Show full text]
  • The State of Biodiversity in Kuwait Zuhair S
    The state of biodiversity in Kuwait Zuhair S. Amr INTERNATIONAL UNION FOR CONSERVATIONO OF NATURE - REGIONAL OFFICE FOR WEST ASIA About Environment Public Authority The Environment Public Authority of Kuwait (EPA) is an independent governmental organization dedicated to environmental action in addition to domestic and international legislation and policy regarding the environment. The Environment Public Authority was founded in 1995 and since then it serves as the epicentre of governmental action regarding the preservation of the environment in Kuwait. Environment and health protection is one of the main priorities of EPA by implementing deliberate plans and projects to protect air, soil, aquatic habitats, coastal habitats, biodiversity, and environmental impact evaluation. EPA focuses on community services and public awareness directed to different groups of the community especially the younger generations as they are the leaders of the future. About IUCN IUCN, International Union for Conservation of Nature with its Headquarters in Gland, Switzerland, was created in 1948 as a membership organisation. IUCN is the world’s first and largest global environmental network. It is a democratic membership union with more than 1,400 government and non- government member organisations, and almost 18,000 volunteer scientists and experts in over 160 countries. IUCN’s work is supported by around 900 professional staff in more than 160 countries and hundreds of partners in public, NGO and private sectors around the world. IUCN seeks to help the world find pragmatic solutions to the most pressing environmental and sustainable development challenges. IUCN supports scientific research, manages field projects all over the world and brings governments, non- government organisations, United Nations agencies, companies and local communities together to develop and implement policy, laws and best practices.
    [Show full text]
  • The Current State of Food Resources Supporting Waterbird and Fish Populations in the Coorong
    The current state of food resources supporting waterbird and fish populations in the Coorong Qifeng Ye, Sabine Dittmann, George Giatas, Ryan Baring, Joshua Nitschke, Luciana Bucater and Deborah Furst Goyder Institute for Water Research Technical Report Series No. 19/33 www.goyderinstitute.org Goyder Institute for Water Research Technical Report Series ISSN: 1839-2725 The Goyder Institute for Water Research is a partnership between the South Australian Government through the Department for Environment and Water, CSIRO, Flinders University, the University of Adelaide, the University of South Australia and the International Centre of Excellence in Water Resource Management. The Institute enhances the South Australian Government’s capacity to develop and deliver science-based policy solutions in water management. It brings together the best scientists and researchers across Australia to provide expert and independent scientific advice to inform good government water policy and identify future threats and opportunities to water security. This program is part of the Department for Environment and Water’s Healthy Coorong Healthy Basin Program, which is jointly funded by the Australian and South Australian governments. The following Associate organisation led this project: Enquires should be addressed to: Goyder Institute for Water Research Level 4, 33 King William Street Adelaide, SA 5000 tel: 08 8236 5200 e-mail: [email protected] Citation Ye, Q., Dittmann, S., Giatas, G., Baring, R., Nitschke, J., Bucater, L. and Furst, D. (2019) The current state of food resources supporting waterbird and fish populations in the Coorong. Goyder Institute for Water Research Technical Report Series No. 19/33. © Crown in right of the State of South Australia, Department for Environment and Water.
    [Show full text]