Evaluating the Long-Term Success of Native Revegetation in the Southern Tablelands, NSW”
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University of Wollongong Research Online Faculty of Science, Medicine & Health - Honours Theses University of Wollongong Thesis Collections 2012 “Evaluating the long-term success of native revegetation in the Southern Tablelands, NSW” Xanthe Willis University of Wollongong Follow this and additional works at: https://ro.uow.edu.au/thsci University of Wollongong Copyright Warning You may print or download ONE copy of this document for the purpose of your own research or study. The University does not authorise you to copy, communicate or otherwise make available electronically to any other person any copyright material contained on this site. You are reminded of the following: This work is copyright. Apart from any use permitted under the Copyright Act 1968, no part of this work may be reproduced by any process, nor may any other exclusive right be exercised, without the permission of the author. 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Recommended Citation Willis, Xanthe, “Evaluating the long-term success of native revegetation in the Southern Tablelands, NSW”, Bachelor of Environmental Science (Honours), School of Earth & Environmental Sciences, University of Wollongong, 2012. https://ro.uow.edu.au/thsci/24 Research Online is the open access institutional repository for the University of Wollongong. For further information contact the UOW Library: [email protected] “Evaluating the long-term success of native revegetation in the Southern Tablelands, NSW” Abstract Deforestation and degradation of productive lands is an environmental issue facing farming communities worldwide. As a result of past land management practices, biodiversity has been impacted and often irreparably damaged and the resulting landscapes can be devoid of the original functioning ecosystems with impacts across both the biotic and abiotic features of the landscape. Increased knowledge over the past 20-30 years has led to an appreciation and improved effort towards maintaining and preserving remnant ecosystems through fencing and ecological restoration efforts. In some areas however, almost total removal of the original ecosystem has occurred and as such, there is little remnant vegetation to base revegetation efforts on. This lack of a benchmark to work towards has impacted on the subsequent success of revegetation plantings in such regions. The Southern Rivers Catchment Management Authority (SRCMA) has identified that there is a need to encourage landholders to revegetate at strategic points across properties, however outcomes of previous revegetation has been quite varied. Previous studies have attempted to explain these variations through analysing certain abiotic or biotic components of the revegetation, though few have attempted to investigate the feedbacks between revegetation and soil and the potential link to successful vegetation recruitment. This study examines those potential relationships in an attempt to determine the limitations to persistence and therefore success of revegetation and how this relates to revegetation management in the wider Southern Tablelands area of NSW. Soil and vegetation samples were collected from seven revegetation sites within the Braidwood district and tested for determinable soil and vegetation characteristic correlations. Results revealed little association between soil characteristics and levels of recruitment, rather indicating that particular vegetative components may be more influential in estrictingr recruitment and continued persistence. These results provide information to decision makers about where best to distribute funding throughout the Southern Tablelands to ensure the benefits of revegetation carried out now continue into the future. The potential for such revegetation to sequester carbon and contribute to future ‘carbon credit’ commodities is also discussed Degree Type Thesis Degree Name Bachelor of Environmental Science (Honours) Department School of Earth & Environmental Sciences Keywords revegetation, soil organic carbon, Southern Tablelands, Braidwood, soil condition This thesis is available at Research Online: https://ro.uow.edu.au/thsci/24 Faculty of Science School of Earth and Environmental Science “Evaluating the long-term success of native revegetation in the Southern Tablelands, NSW” By Xanthe Willis A research report submitted in partial fulfilment of the requirements for the award of the degree of Bachelor of Environmental Science (Honours) May 2012 The information in this thesis is entirely the result of investigations conducted by the author, unless otherwise acknowledged, and has not been submitted in part, or otherwise, for any other degree or qualification. - Xanthe Willis ~ ii ~ ABSTRACT Deforestation and degradation of productive lands is an environmental issue facing farming communities worldwide. As a result of past land management practices, biodiversity has been impacted and often irreparably damaged and the resulting landscapes can be devoid of the original functioning ecosystems with impacts across both the biotic and abiotic features of the landscape. Increased knowledge over the past 20-30 years has led to an appreciation and improved effort towards maintaining and preserving remnant ecosystems through fencing and ecological restoration efforts. In some areas however, almost total removal of the original ecosystem has occurred and as such, there is little remnant vegetation to base revegetation efforts on. This lack of a benchmark to work towards has impacted on the subsequent success of revegetation plantings in such regions. The Southern Rivers Catchment Management Authority (SRCMA) has identified that there is a need to encourage landholders to revegetate at strategic points across properties, however outcomes of previous revegetation has been quite varied. Previous studies have attempted to explain these variations through analysing certain abiotic or biotic components of the revegetation, though few have attempted to investigate the feedbacks between revegetation and soil and the potential link to successful vegetation recruitment. This study examines those potential relationships in an attempt to determine the limitations to persistence and therefore success of revegetation and how this relates to revegetation management in the wider Southern Tablelands area of NSW. Soil and vegetation samples were collected from seven revegetation sites within the Braidwood district and tested for determinable soil and vegetation characteristic correlations. Results revealed little association between soil characteristics and levels of recruitment, rather indicating that particular vegetative components may be more influential in restricting recruitment and continued persistence. These results provide information to decision makers about where best to distribute funding throughout the Southern Tablelands to ensure the benefits of revegetation carried out now continue into the future. The potential for such revegetation to sequester carbon and contribute to future ‘carbon credit’ commodities is also discussed. ~ iii ~ ACKNOWLEDGEMENTS I must first extend my most sincere thanks to my University supervisors, Tim and Kris, your belief in my skills, your enthusiasm, technical help and feedback were invaluable and the help throughout this project was greatly appreciated. Also thanks to my industry supervisor, Donna, for providing insightful gems of wisdom at strategic points throughout this project. Thank you to the Southern Rivers Catchment Management Authority employees, who are a priceless wealth of knowledge which they willingly shared with me. Special thank you to Felicity and Kristy for your enthusiasm and guidance, and the kind offers of accommodations. Special and most sincere thanks to Sky who tirelessly helped me identify the large range of plants I turned up on your door with and who made me feel most welcome at your home. Also to Stella for her tireless help during fieldwork, who knew soil sampling could be so hilarious? Special thank you to the landholders who so willingly allowed me onto their properties and were always welcoming and very helpful with my many questions. Thank you to Heidi, I am convinced you are a spatial analyst genius, your guidance, encouragement and numerous chats helped me immensely. To my long suffering friends; thank you for all the sympathetic comments throughout my standard ‘honours rant’ this past year. Also thank you to my housemates who strategically realised when I needed room, and also when I needed company. Finally, thank you to my family. Your encouragement and support were always very much appreciated, even if I didn’t show it at times. ~ iv ~ TABLE OF CONTENTS ABSTRACT ................................................................................................................................. iii ACKNOWLEDGEMENTS ............................................................................................................... iv LIST OF FIGURES