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System Dynamics Modelling for Dryland Salinity Strategic Management: a Methodological Investigation

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System Dynamics Modelling for Dryland Salinity Strategic Management: a Methodological Investigation System Dynamics Modelling for Dryland Salinity Strategic Management: A Methodological Investigation By Naeem Ullah Khan B.Sc. (Hons) Agriculture (Faisalabad, Pakistan) M.Sc. Natural Resources Planning and Management (AIT-Thailand) M.Sc. Sustainable Agriculture (Aberdeen, UK) A thesis submitted for the Degree of Doctor of Philosophy School of Engineering and Information Technology University College University of New South Wales Canberra, Australia 2012 ABSTRACT This thesis examines the nature of dryland salinity, its causes and the difficulties that arise in its management. Why such problematic situations are confounding to manage is examined, noting particularly that humankind’s actions over two centuries have played a dominant role in creating dryland salinity as we know it in Australia today. This research aims to define an improved methodological approach for designing management strategies that are likely to produce enduring results. It also aims to identify the likely effectiveness of alternate strategies and the timeframes over which results might be achieved. To do this, a multi-methodology approach is taken, one which combines an understanding of feedback dynamics and one which sets out to improve the rigour of investigations into complex systems. The key methodologies are System Dynamics Modelling and Systems Engineering. How these methodologies were applied in an attempt to design highly effective strategies is described. Lessons for applying the methodologies individually and in combination are described, as are the candidate strategies for alleviating dryland salinity both in Australia and in other parts of the world where its effects are similarly devastating. ii PUBLICATIONS Khan, N.U., McLucas, A.C. and Linard, K. (2004). Development of a Reference Mode for Characterization of the Salinity Problem in the Murray Darling Basin. In Proceedings of 22nd International System Dynamics Society Conference, Oxford, UK, System Dynamics Society. Khan, N.U. and McLucas A.C. (2006). Development of a Strategic System Dynamics Model of Dryland Salinity. In: Proceedings of 24th the International System Dynamics Society Conference, Nijmegen, The Netherlands, System Dynamics Society. Khan, N.U. and McLucas A.C. (2008). A Case Study in Application of Vee Model of Systems Engineering to System Dynamics Modelling of Dryland Salinity in Australia. In: Proceedings of the 26th International System Dynamics Society Conference, Athens, Greece, System Dynamics Society. Khan, N.U. and McLucas A.C. (2008). Application of Systems Engineering Vee Model to Enhance System Dynamics Modelling Methodology. In: Proceedings of the Systems Engineering and Test and Evaluation (SETE) Conference, Canberra, Australia, Systems Engineering Society of Australia. iii ACKNOWLEDGEMENTS I am grateful to my supervisor Dr Alan McLucas for his encouragement, tireless review of my written work and guidance on the direction of this research, particularly at the times when there was a changing focus consequent upon the outcome of preceding research. He provided an environment for original thinking and critical review of different systems methodologies for strategy development. He also provided me with opportunities for teaching system dynamics courses to graduate students. This was critical in self-analysis about the methodology through presentation, interactions with graduate students and feedback, and it also provided some financial assistance in a time of need. I am thankful to Keith Linard, the former Director of the UNSW Center for Business Dynamics and Knowledge Management and Robert Niven for their valuable time and thought provoking discussions in the initial conceptualisation of the project. For prompt response to my requests for information and data, I am thankful to Dr Mark Littleboy, NSW Department of Land and Water Conservation; Colin Mues of the Australian Bureau of Agricultural and Resource Economics; Brad Powel Murrumbidgee Irrigation; Andrew Close, Matt Kendall and Judy Swan from the Murray Darling Basin Commission; Garry Richard and Ashley Fuller from the Australian Greenhouse Office; Numerous data providers from the Australian Bureau of Statistics and Andrew Hollis from the National Climate Centre, Bureau of Meteorology. A major part of the study was accomplished as a part-time student being in full-time employment at the Policy and Planning Branch of the Department of Immigration and Citizenship. I am thankful to Daniel Caldwell, Kristina Crnagoj, Robert Johnston, Christopher Lanspeary, Jan Tankiang and Andrew Bleeze for intermittent study leave approvals. It is a pleasure to work in an organisation that values an understanding of individual needs, encourages personal development and work life balance. iv I am also thankful to Professor Michael Frater, Head of the School of Information Technology and Electrical Engineering and Professor Steve Yeoman, the then Head of the School of Civil Engineering for providing a workplace for this study. I thank the anonymous reviewers of my papers and audience at the International System Dynamics Society Conference at Oxford, Nimjegen and Athens, and Systems Engineering Test and Evaluation Conference in Canberra for their critical and useful comments and feedback. I am also thankful to Ms Katie Poidomani for proofreading of the final manuscript. I am also grateful to my elder brother Naseem Ullah Khan for his encouragement towards higher ideals in life and particularly during completion of my doctoral studies. For her patience, understanding and love during this particularly busy period, I am thankful to Afroz. The cheerful smiles of Aleena and Talal kept reminding me to successfully finish my studies. v Contents Chapter 1 Introduction 1-1 1.1 Motivation 1-2 1.2 Research Gap, Challenges and Benefits 1-8 1.3 Purpose of Inquiry 1-9 1.4 Scope of Study 1-10 1.5 Study Area 1-11 1.6 Publications 1-12 1.7 Thesis Structure 1-13 Chapter 2 Dryland Salinity - A Complex Problem 2-1 2.1 Defining Dryland Salinity 2-2 2.1.1 Classification of Salt Affected Lands 2-3 2.2 Extent of the Dryland Salinity Problem 2-4 2.2.1 Global Extent 2-4 2.2.2 Dryland Salinity in Australia 2-6 2.3 Significance of the Dryland Salinity Problem 2-6 2.4 Varying Explanations about Causes of Dryland Salinity 2-8 2.4.1 The FAO Model 2-9 2.4.2 PMSEIC Model 2-10 2.4.3 Acworth and Jankowsky Model 2-14 2.5 Other Factors Affecting Dryland Salinity 2-15 2.5.1 Climate 2-15 2.5.2 Land cover/Land use 2-16 2.5.3 Salt Stores 2-18 2.5.4 Hydrogeology Characteristics 2-19 2.5.5 Local Flow System 2-21 2.5.6 Regional Flow System 2-22 2.6 Control Options 2-24 2.6.1 Engineering Options 2-25 2.6.2 Plant-Based Options 2-29 vi 2.6.3 Living with Salts 2-35 2.6.4 Other dryland salinity policies and unused points of entry 2-35 2.7 Summary and Conclusion 2-38 Chapter 3 Models, Tools and Decision Support Systems for Dryland Salinity Management 3-1 3.1 Defining A Model, Tool or Decision Support System 3-2 3.1.1 Model 3-2 3.1.2 Decision Support Systems and Tools 3-2 3.2 Existing Models, Tools and Decision Support Systems 3-3 3.2.1 Models of Physical Processes 3-7 3.2.1.1 Soil Water and Groundwater Simulation (SWAGSIM) 3-7 3.2.1.2 Grassland Water District Decision Support System 3-10 (Quinn and Hanna, 2003) 3.2.2 Spatial Models 3-12 3.2.3 Bio-economic Models 3-12 3.2.3.1 Salinity and Land Use Simulation Analysis (SALSA) 3-13 3.2.4 Dynamic Models 3-14 3.2.5 Integrated Modelling Frameworks and the Practice of Using Multiple Models 3-17 3.2.6 Information Frameworks 3-18 3.3 Issues in Modelling For Management of Dryland Salinity 3-18 3.3.1 Model Boundary and Varying Levels of Focus 3-19 3.3.2 Emergence 3-20 3.3.3 Dynamic Complexity 3-21 3.3.4 Time Delays 3-24 3.3.5 Complexity and Modelling 3-24 3.4 Summary and Conclusions 3-26 Chapter 4 System Dynamics 4-1 4.1 What is System Dynamics? 4-2 4.1.1 Definitions 4-2 4.1.2 Purpose of Inquiry in a System Dynamics Study 4-3 vii 4.2 Philosophy Underlying System Dynamics 4-5 4.2.1 Principles of Systems 4-6 4.2.2 Rationality in System Dynamics 4-7 4.3 System Dynamics Methodology 4-9 4.4 System Dynamics Practice 4-15 4.4.1 A Brief History of System Dynamics Applications 4-15 4.4.2 Quantitative and Qualitative Debate 4-18 4.5 Summary and Conclusion 4-19 Chapter 5 A Multi-Methodology Framework 5-1 5.1 Need for Multi-Methodology 5-3 5.2 Multi-Methodology Philosophy 5-3 5.3 Current Use of System Dynamics with other Systems Methodologies 5-12 5.4 A Multi-Methodology Framework to Enhance System Dynamics Modelling Process 5-13 5.4.1 Cognitive Mapping/Concept Mapping 5-14 5.4.2 System Dynamics 5-17 5.4.3 Systems Engineering 5-17 5.4.4 Strengths of using Systems Engineering in conjunction with System Dynamics 5-22 5.5 Summary and Conclusions 5-25 Chapter 6 Reference Mode Development 6-1 6.1 Why Reference Modes are needed? 6-3 6.2 Method for Reference Modes Development 6-3 6.3 Data for Developing Reference Modes 6-6 6.4 Domain Boundary 6-7 6.4.1 Snapshots of Current Situation 6-7 6.4.2 Concerns about Salinity Data 6-8 6.4.3 Climate 6-9 6.4.4 Land Use 6-9 viii 6.4.5 River Water Diversions and Salt Carrying Capacity of Rivers 6-10 6.4.6 Delays 6-11 6.5 Key Variables 6-12 6.5.1 Time Series Data 6-12 6.5.2 Farmers’ Perceptions about the Past and Future of Dryland Salinity 6-19 6.5.3 Delineation of the Domain Boundary 6-24 6.6 Preliminary System Boundary 6-24 6.6.1 Step 5-Examination of Variables 6-25 6.6.2 Steps 6 and 7 6-26 6.6.3 Step-8 6-26 6.7 Preliminary Model Boundary 6-27 6.7.1 Step-9 Examine Selected Group of Patterns 6-27 6.7.2 Step-10 Aggregate
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