Riverland Ramsar Site Ecological Character Description Riverland Ramsar Site Ecological Character Description by Peter Newall, Lance Lloyd, Peter Gell and Keith Walker Project No: LE0739 11th June 2008 Revised 13th July 2009 Riverland Ramsar Site ECD…4 Contents ACKNOWLEDGEMENTS ...................................................................................................................................... 6 LIST OF ABBREVIATIONS ............................................................................................................................... 7 EXECUTIVE SUMMARY ....................................................................................................................................... 8 1. INTRODUCTION ......................................................................................................................................... 24 1.1. PURPOSE ..................................................................................................................................................... 24 1.2. SITE DETAILS ............................................................................................................................................. 25 1.3. DATE OF DESCRIPTION.............................................................................................................................. 27 1.4. RELEVANT TREATIES, LEGISLATION OR REGULATIONS .......................................................................... 27 1.4.1 International treaties and strategies .................................................................................... 27 Ramsar Convention ...................................................................................................................................... 27 1.4.2 Commonwealth Legislation and Policy ................................................................................ 29 1.4.3 State Legislation .......................................................................................................................... 29 2. DESCRIPTION OF THE SITE ................................................................................................................ 31 2.1 SETTING...................................................................................................................................................... 31 2.2 RIVERLAND RAMSAR SITE ......................................................................................................................... 33 2.2.1 Murtho Block .................................................................................................................................. 33 2.2.2 Calperum Block ............................................................................................................................ 33 2.2.3 Chowilla Block ............................................................................................................................... 33 2.3 OVERVIEW OF RAMSAR SITE .................................................................................................................... 36 2.4 RAMSAR LISTING ....................................................................................................................................... 41 Criterion 1 (representative/rare/unique wetland type in appropriate biogeographic region) ............................................................................................................................................................... 42 Criterion 2 (vulnerable/endangered/critically endangered species or ecological communities) .................................................................................................................................................. 42 Criterion 3 (supports populations of plant and/or animals important for regional biodiversity) .................................................................................................................................................... 44 Criterion 4 (supports species at critical stages or provides refuge in adverse conditions) ............................................................................................................................................................................. 45 Criterion 5 (providing habitat that regularly supports 20,000 or more waterbirds) ........... 46 Criterion 6 (providing habitat that regularly supports 1% of the global population of one species of waterbird) ................................................................................................................................... 48 Criterion 7 (supporting a significant proportion of indigenous fish taxa, life-history stages, species interactions or populations that are representative of wetland benefits and/or values) ................................................................................................................................................ 49 Criterion 8 (supplying an important food source, spawning ground, nursery and/or migration path for fishes, on which fish stocks depend) ............................................................... 50 2.5 LAND USE AND TENURE ............................................................................................................................ 52 3. ECOLOGICAL CHARACTER OF THE RIVERLAND RAMSAR SITE ....................................... 54 3.1 GENERAL DESCRIPTION ............................................................................................................................. 54 3.2 COMPONENTS OF THE SITE ....................................................................................................................... 56 3.2.1 Climate ............................................................................................................................................ 56 3.2.2 Geomorphology ............................................................................................................................ 58 3.2.3 Soils .................................................................................................................................................. 64 3.2.4 Hydrology ....................................................................................................................................... 64 3.2.5 Water Quality ................................................................................................................................ 71 3.2.6 Vegetation and Habitat .............................................................................................................. 73 3.2.7 Vegetation and Inundation Level ........................................................................................... 88 3.2.8 Fauna................................................................................................................................................ 94 Riverland Ramsar Site ECD…5 3.2.9 Critical components of the Site .............................................................................................. 98 3.3 PROCESSES OF THE SITE .......................................................................................................................... 98 3.4 BENEFITS AND SERVICES OF THE SITE .................................................................................................. 100 3.5 CONCEPTUAL MODELS OF THE SITE ....................................................................................................... 108 3.5.1 Landscape conceptual models .............................................................................................. 108 3.5.2 Flood levels and vegetation communities ........................................................................ 112 3.5.3 Biological processes .................................................................................................................. 119 3.5.4 Physico-chemical processes................................................................................................... 120 3.5.5 Groundwater processes ........................................................................................................... 121 3.6 KEY ACTUAL OR POTENTIAL THREATS TO THE SITE ............................................................................. 122 3.7 LIMITS OF ACCEPTABLE CHANGE ............................................................................................................ 127 4. CHANGES IN ECOLOGICAL CHARACTER SINCE LISTING ................................................. 151 5. KNOWLEDGE GAPS ................................................................................................................................. 159 6. KEY SITE MONITORING NEEDS ...................................................................................................... 161 7. COMMUNICATION, EDUCATION AND PUBLIC AWARENESS (CEPA) MESSAGES 165 8. GLOSSARY ................................................................................................................................................... 173 9. REFERENCES .............................................................................................................................................. 176 10. APPENDICES .......................................................................................................................................... 184 10.1 APPENDIX 1: FLORA OF THE RIVERLAND RAMSAR SITE .................................................................. 184 10.1.1 List of dominant plant species for major vegetation