A Grassy Woodland
Total Page:16
File Type:pdf, Size:1020Kb
EVALUATION OF RESTORATION: A GRASSY WOODLAND BY PETER WILLIAM BROUGHTON NICHOLS A Thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy at the University of Western Sydney © Peter Nichols 2005 Acknowledgements A work of this scale would not have been possible without the assistance of several people. The author would like to express gratitude to the following people for assistance throughout the completion of this Thesis. Firstly, I would like to thank my supervisors Dr E. Charles Morris (University of Western Sydney) and Dr David Keith (National Parks and Wildlife Service) for their support and guidance throughout all phases of the project. Both have provided timely advice throughout the project and critical comments on the many versions of the draft Thesis. Their assistance has been much appreciated. Particular thanks go to Peter Wood for his assistance with fieldwork, species identification and comments on draft versions of the Thesis. Thanks are also due to several people who assisted with fieldwork and provided general advice and comment including: Jeanette Lawrence, Paul Nichols, Monique de Barse and Jennifer Fitzgerald. In addition, thanks go to several people working for Greening Australia for help with access to sites and fieldwork equipment and historical documents including Dave Warren, Dan Williams and Judy Christie. I would especially like to thank my parents-in-law, Alma and Howard Dudgeon for their child minding efforts and my parents, Denise and Alan and Nichols for their timely encouragement and support, especially through the writing phase of the Thesis. Finally, I would like to thank my wife Coralie Nichols for her patience, good humour and support throughout. Without your love and support, this project would not have been possible. Thank you. ii Declaration I certify that this Thesis has not already been submitted for any degree and is not currently being submitted for any other degree or qualification. I certify that this work is original and a result of my own research. To the best of my knowledge and belief, this Thesis does not contain any material published or written by other persons, except where due reference is made in the text. Signed, PETER W. B. NICHOLS Date: iii Table of Contents Acknowledgements.........................................................................................................ii Declaration ................................................................................................................ iii Table of Contents ..........................................................................................................iv List of Tables .............................................................................................................. viii List of Figures...............................................................................................................xii Appendices ................................................................................................................xv Summary ...............................................................................................................xvi Chapter 1 ..................................................................................................................1 Introduction, rationale for study and case study details ............................................1 1.1 Introduction........................................................................................................... 1 Land degradation in Australia................................................................2 Revegetation as a form of restoration ....................................................4 Current policy in Australia on revegetation...........................................4 1.2 Restoration planning............................................................................................. 6 1.3 Evaluation of Restoration ..................................................................................... 9 1.4 State and transition models of vegetation dynamics........................................... 14 1.5 Rationale for this study....................................................................................... 15 1.6 Previous work ..................................................................................................... 16 1.7 Case study: Cumberland Plain Woodland (CPW).............................................. 17 Chapter 2 Study location.......................................................................................23 2.1 Introduction......................................................................................................... 23 2.2 Study sites........................................................................................................... 31 2.2.1 Hoxton Park (HP) .......................................................................33 2.2.2 Plough and Harrow (P&H) .........................................................34 2.2.3 Western Sydney Regional Park (WSRP)....................................35 2.2.4 Prospect Reservoir (Prospect, PR)..............................................37 Chapter 3 Measuring the Success of Revegetation .............................................39 3.1 Introduction......................................................................................................... 39 3.2 Methods .............................................................................................................. 43 Restoration treatment ...........................................................................43 Sampling approach...............................................................................44 Sampling design...................................................................................45 Site selection ........................................................................................46 Data collection .....................................................................................50 Species composition.............................................................................50 Vegetation structure.............................................................................52 iv Environmental data ..............................................................................52 Data analyses .......................................................................................53 Species composition.............................................................................53 Species richness ...................................................................................53 Comparisons amongst treatments ........................................................53 Community composition......................................................................54 Native species returning or not returning to restored pasture as a result of revegetation .....................................................................................55 Temporal development of species composition...................................55 Species contribution: Percentage similarity and dissimilarity.............55 Plant groups .........................................................................................56 Vegetation structure.............................................................................56 Tree height, foliage cover, percentage cover of rock, bare ground, lichen and litter ....................................................................................56 Environmental variation.......................................................................56 3.3 Results ................................................................................................................ 58 Species richness- total species .............................................................58 Species richness- native species (excluding planted species)..............58 Species richness- native species (including planted species) ..............60 Species richness- proportion of exotic species ....................................62 Species richness- exotic species...........................................................64 Vegetation community composition....................................................66 All species (excluding planted species) ...............................................66 All species (including planted species)................................................67 Native species (excluding planted species)..........................................68 Exotic species.......................................................................................69 Native species returning after restoration ............................................70 Plant groups .........................................................................................74 Temporal development of species composition...................................75 Species contribution: Comparisons within vegetation communities ...76 Pasture..................................................................................................76 Young revegetation..............................................................................77 Old Revegetation .................................................................................78 Remnant vegetation .............................................................................79 Species contribution: Comparisons between vegetation communities 80 Species abundance changes after restoration.......................................82 Native species