SUSTAINING THE WET TROPICS: A REGIONAL PLAN FOR NATURAL RESOURCE MANAGEMENT VOLUME 2B CONDITION REPORT: SUSTAINABLE USE J. Armour1, L. Cogle1, V. Rasiah1 and J. Russell2 1Department of Natural Resources and Mines, Mareeba 2 Northern Fisheries Centre, Cairns Established and supported under the Australian Cooperative Research Centres Program © Cooperative Research Centre for Tropical Rainforest Ecology and Management, and FNQ NRM Ltd. ISBN 0 86443 712 9 This work is copyright. The Copyright Act 1968 permits fair dealing for study, research, news reporting, criticism or review. Selected passages, tables or diagrams may be reproduced for such purposes provided acknowledgment of the source is included. Major extracts of the entire document may not be reproduced by any process without written permission of either the Chief Executive Officer, Cooperative Research Centre for Tropical Rainforest Ecology and Management, or Executive Officer, FNQ NRM Ltd. Published by the Cooperative Research Centre for Tropical Rainforest Ecology and Management. Further copies may be obtained from FNQ NRM Ltd, PO Box 1756, Innisfail, QLD, Australia, 4860. This publication should be cited as: Armour, J., Cogle, L., Rasiah, V., and Russell, J. (2004), Sustaining the Wet Tropics: A Regional Plan for Natural Resource Management, Volume 2B Condition Report: Sustainable Use. Rainforest CRC and FNQ NRM Ltd, Cairns (115 pp). January 2004 Cover Photos: Top: Richard Pearson Centre: Great Barrier Reef Marine Park Authority Bottom: Richard Pearson CONDITION REPORT: SUSTAINABLE USE i PREFACE Managing natural resources for sustainability and ecosystem health is an obligation of stakeholders at all levels. At the State and Commonwealth government level, there has been a shift over the last few years from the old project-based approach to strategic investment at a regional scale. To oversee this investment, regional natural resource management (NRM) bodies have been established across Queensland and Australia. The new NRM Board for the Wet Tropics region, FNQ NRM Ltd, was appointed in late 2003. The aim of this community-based Board is to take the Wet Tropics to the forefront of conservation and sustainable use of natural resources through strengthened community participation. One of the first tasks of the new Board is the preparation of a new NRM Plan for the Wet Tropics to strategically focus investment while incorporating the outcomes of previous planning in the region. At a high-level regional science meeting held in November 2002, it was agreed that the Plan should be based on a clear documentation of the state of resources in the region. While there is a wealth of research publications on the region, there has been no synthesis of this material into a document for the consultation and plan preparation processes. This is the purpose of the current report. The information in this report deals with the second of the three overarching objectives that will direct decision-making under the extension of the NHT Program, namely sustainable use of natural resources. It is the third of a series of documents that will be co-produced as supporting information to the Plan (see introduction to this report). The principal authors of this report were John Armour, Lex Cogle and Velu Rasiah from the Land and Water Science Group, NR&M, Mareeba and John Russell from the Northern Fisheries Centre, DPI, Cairns. The authors wish to acknowledge the contribution made by others, including those who reviewed the document as organisational representatives. The Commonwealth and State governments should also be thanked for their support through the NHT Program extension. This report is designed to be used by planners and decision-makers involved in the development of the Wet Tropics NRM Plan. It should also be of use to others involved in NRM in the private sector and at the local, State and Commonwealth government levels. Indigenous and community groups, students and the public generally should also find the report, and those that follow, a valuable resource. I take pleasure in presenting it to the regional community. Mike Berwick Chair, FNQ NRM Ltd ii SUSTAINING THE WET TROPICS: A REGIONAL PLAN FOR NRM TABLE OF CONTENTS PREFACE....................................................................................................................... I LIST OF TABLES ........................................................................................................ V LIST OF ACRONYMS .............................................................................................. VI 1. INTRODUCTION.................................................................................................1 1.1. THIS REPORT...............................................................................................1 1.2. SUSTAINABLE USE – WHAT IS IT? .........................................................1 1.3. AIMS OF THE REPORT...............................................................................1 1.4. REPORT FRAMEWORK..............................................................................2 1.5. REPORT PREPARATION ............................................................................2 1.6. DATA ACQUISITION ..................................................................................2 2. WATER HEALTH (INCLUDING SURFACE WATER, GROUND WATER AND WETLANDS)...............................................................................................3 2.1. QUALITY ......................................................................................................3 2.1.1. DEFINITION.........................................................................................3 2.1.2. CONDITIONS, TRENDS AND CURRENT STATE OF KNOWLEDGE......................................................................................5 2.1.3. CRITICAL ISSUES, IMPACTS AND THREATS.............................15 2.1.4. CURRENT STATE OF UNDERSTANDING ....................................16 2.1.5. ACTIONS FOR SUSTAINABLE USE...............................................17 2.1.6. INSTITUTIONAL ARRANGEMENTS .............................................17 2.2. QUANTITY .................................................................................................18 2.2.1. DEFINITION.......................................................................................18 2.2.2 CONDITION, TRENDS AND CURRENT STATE OF KNOWLEDGE .............................................................................................................18 2.2.3. CRITICAL ISSUES, IMPACTS AND THREATS.............................22 2.2.4. CURRENT STATE OF UNDERSTANDING ....................................23 2.2.5. POTENTIAL ACTIONS FOR SUSTAINABLE USE........................23 2.2.6. INSTITUTIONAL AND ADMINISTRATIVE ARRANGEMENTS.24 3. SOIL HEALTH ...................................................................................................26 3.1. ACIDIFICATION ........................................................................................26 3.1.1. DEFINITION.......................................................................................26 3.1.2. CONDITION, TRENDS AND CURRENT STATE OF KNOWLEDGE .............................................................................................................27 3.1.3. CRITICAL ISSUES, IMPACTS AND THREATS.............................29 3.1.4. CURRENT STATE OF UNDERSTANDING ....................................29 3.1.5. POTENTIAL ACTIONS FOR SUSTAINABLE USE........................29 3.2. ACID SULFATE SOILS..............................................................................30 3.2.1. DEFINITION.......................................................................................30 3.2.2. CONDITION, TRENDS AND CURRENT STATE OF KNOWLEDGE .............................................................................................................30 3.2.3. CRITICAL ISSUES, IMPACTS AND THREATS.............................31 3.2.4. CURRENT STATE OF UNDERSTANDING ....................................32 3.2.5. POTENTIAL ACTIONS FOR SUSTAINABLE USE........................32 3.2.6. INSTITUTIONAL AND ADMINISTRATIVE ARRANANGEMENTS .............................................................................................................33 3.3. SOIL EROSION (HILLSLOPE, GULLY, BANK) .....................................33 3.3.1. DEFINITION.......................................................................................33 3.3.2. CONDITION, TRENDS AND CURRENT STATE OF KNOWLEDGE .............................................................................................................34 3.3.3. CRITICAL ISSUES, IMPACTS AND THREATS.............................35 3.3.4. CURRENT STATE OF UNDERSTANDING ....................................36 3.3.5. POTENTIAL ACTIONS FOR SUSTAINABLE USE........................36 CONDITION REPORT: SUSTAINABLE USE iii 3.4. SALINITY....................................................................................................39 3.4.1. DEFINITION.......................................................................................39 3.4.2. CONDITION, TRENDS AND CURRENT STATE OF KNOWLEDGE .............................................................................................................39 3.4.3. CRITICAL ISSUES, IMPACTS AND THREATS.............................39 3.4.4 CURRENT STATE OF UNDERSTANDING ....................................40 3.4.5 POTENTIAL ACTIONS FOR SUSTAINABLE USE........................40 3.5 FERTILITY DECLINE