Impact of Cruise Ship Turbulence on Benthic Communities Case Study in Tasmania's South-West

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Impact of Cruise Ship Turbulence on Benthic Communities Case Study in Tasmania's South-West IMPACT OF CRUISE SHIP TURBULENCE ON BENTHIC COMMUNITIES CASE STUDY IN TASMANIA'S SOUTH-WEST By Claire Ellis, Neville Barrett and Sophia Schmieman Case study in Tasmania’s south-west Technical Reports The technical report series present data and its analysis, meta-studies and conceptual studies, and are considered to be of value to industry, government and researchers. Unlike the Sustainable Tourism Cooperative Research Centre’s Monograph series, these reports have not been subjected to an external peer review process. As such, the scientific accuracy and merit of the research reported here is the responsibility of the authors, who should be contacted for clarification of any content. Author contact details are at the back of this report. Editors Prof Chris Cooper University of Queensland Editor-in-Chief Prof Terry De Lacy Sustainable Tourism CRC Chief Executive Prof Leo Jago Sustainable Tourism CRC Director of Research National Library of Australia Cataloguing in Publication Data Ellis, Claire F. Impact of cruise ship turbulence on benthic communities: case study in Tasmania's south west. Bibliography. ISBN 1 920704 41 8. 1. Environmental impact analysis - Tasmania. 2. Benthos - Tasmania. 3. Environmental monitoring - Tasmania. 4. Plants - Effect of turbulence on - Tasmania. I. Barrett, Neville. II. Schieman, Sophia. III. Cooperative Research Centre for Sustainable Tourism. IV. Title. 577.7727 Copyright © CRC for Sustainable Tourism Pty Ltd 2005 All rights reserved. Apart from fair dealing for the purposes of study, research, criticism or review as permitted under the Copyright Act, no part of this book may be reproduced by any process without written permission from the publisher. Any enquiries should be directed to Brad Cox, Communications Manager [[email protected]] or Trish O’Connor, Publishing Manager [[email protected]]. ii IMPACT OF CRUISE SHIP TURBULENCE ON BENTHIC COMMUNITIES Contents ABSTRACT ____________________________________________________________________________ VI ACKNOWLEDGEMENTS ________________________________________________________________ VI SUMMARY ____________________________________________________________________________VII CHAPTER 1 ____________________________________________________________________________ 1 TWWHA AND MARINE PROTECTED AREA MANAGEMENT _______________________________ 1 BACKGROUND _________________________________________________________________________ 1 GROWTH IN CRUISING __________________________________________________________________ 2 THE NEED FOR RESEARCH_______________________________________________________________ 2 GEOGRAPHICAL AND ENVIRONMENTAL FEATURES _______________________________________ 2 VALUES________________________________________________________________________________ 3 GEOMORPHOLOGY ______________________________________________________________________ 3 HYDROLOGY ___________________________________________________________________________ 3 WEATHER AND WAVE GENERATION _________________________________________________________ 3 STRATIFICATION ________________________________________________________________________ 6 HALOCLINE____________________________________________________________________________ 6 WATER CIRCULATION____________________________________________________________________ 6 SIGNIFICANCE OF THE HALOCLINE AND STRATIFICATION _________________________________________ 6 BIOLOGICAL MARINE ENVIRONMENT ____________________________________________________ 7 FISH _________________________________________________________________________________ 7 MARINE PLANTS ________________________________________________________________________ 7 CHAPTER 2 ____________________________________________________________________________ 8 VESSEL IMPACT MODELLING __________________________________________________________ 8 WAVE GENERATION AND DESIGN________________________________________________________ 8 COEFFICIENT OF DRAG ___________________________________________________________________ 8 FETCH LENGTH _________________________________________________________________________ 8 FORECASTING EQUATIONS ________________________________________________________________ 9 PREDICTED VALUES _____________________________________________________________________ 9 CRUISE VESSEL OPERATIONS____________________________________________________________ 9 VESSEL GENERATED SURFACE WAVES______________________________________________________ 10 BACKGROUND TO VESSEL WAVE WAKE_____________________________________________________ 10 ANALYSIS OF VESSEL WAVE WAKE _____________________________________________________ 12 LOCATIONS ___________________________________________________________________________ 12 AMC WAVE WAKE DATABASE ___________________________________________________________ 13 TEST PROGRAM _______________________________________________________________________ 13 RESULTS ______________________________________________________________________________ 13 CONDITION 1__________________________________________________________________________ 13 CONDITION 2__________________________________________________________________________ 17 CONDITION 3__________________________________________________________________________ 20 CONCLUSIONS_________________________________________________________________________ 23 PROPELLER FLOW ______________________________________________________________________ 23 PROPELLER SCOURING __________________________________________________________________ 24 TURBULENT JET THEORY ________________________________________________________________ 26 ANALYSIS OF PROPELLER FLOW ________________________________________________________ 27 PROPELLER SCOURING RESULTS___________________________________________________________ 27 TURBULENT JET THEORY RESULTS_________________________________________________________ 29 APPLICATION OF FACTOR OF SAFETY _______________________________________________________ 31 CONCLUSIONS_________________________________________________________________________ 31 BOUNDARY LAYER DISTURBANCE______________________________________________________ 32 MARINE POLLUTION ___________________________________________________________________ 32 ENVIRONMENTAL SUMMARY AND RECOMMENDATIONS _________________________________ 32 SUMMARY____________________________________________________________________________ 32 RECOMMENDATIONS____________________________________________________________________ 33 FURTHER WORK _______________________________________________________________________ 33 NOMENCLATURE ______________________________________________________________________ 33 ABBREVIATIONS ______________________________________________________________________ 34 iii Case study in Tasmania’s south-west CHAPTER 3 ___________________________________________________________________________ 35 VERIFICATION OF MODEL PREDICTIONS ______________________________________________ 35 INTRODUCTION _______________________________________________________________________ 35 TRIAL 1: EFFECT OF VESSEL WAKE ON WATER COLUMN__________________________________ 35 BACKGROUND_________________________________________________________________________ 35 METHODOLOGY _______________________________________________________________________ 35 RESULTS _____________________________________________________________________________ 36 DISCUSSION __________________________________________________________________________ 39 SUMMARY____________________________________________________________________________ 40 TRIAL 2: VISIT OF AKADEMIC SHOKALSKY TO BATHURST CHANNEL ________________________ 40 METHODS ____________________________________________________________________________ 40 RESULTS _____________________________________________________________________________ 40 DISCUSSION __________________________________________________________________________ 41 SUMMARY____________________________________________________________________________ 42 CHAPTER 4 ___________________________________________________________________________ 43 DISSEMINATION OF RESEARCH OUTCOMES ___________________________________________ 43 INTRODUCTION _______________________________________________________________________ 43 METHOD ______________________________________________________________________________ 43 WEBSITE _____________________________________________________________________________ 43 GRAPHICS ____________________________________________________________________________ 44 POSTER ______________________________________________________________________________ 44 CHAPTER 5 ___________________________________________________________________________ 45 OUTCOMES AND OPPORTUNITIES _____________________________________________________ 45 CONCLUSIONS_________________________________________________________________________ 45 APPENDIX A: WEBSITE TEXT __________________________________________________________ 46 APPENDIX B: PROMOTIONAL POSTER _________________________________________________ 53 REFERENCES _________________________________________________________________________ 54 GLOSSARY____________________________________________________________________________ 55 AUTHORS_____________________________________________________________________________ 56 iv IMPACT OF CRUISE SHIP TURBULENCE ON BENTHIC COMMUNITIES LIST OF FIGURES Figure 1: Temperature Data ________________________________________________________________4 Figure 2: Rainfall Data ____________________________________________________________________4 Figure 3: Wind
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