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Forest ecosystem services for agricultural risk reduction: examining interactions within socio-ecological systems in Madagascar, University of Southampton, Faculty of Social, Human and Mathematical Sciences, Geography and Environment, PhD Thesis, 218p. Data: Dave, R. (2016). Forest ecosystem services for agricultural risk reduction: examining interactions within socio-ecological systems in Madagascar. UNIVERSITY OF SOUTHAMPTON FACULTY OF SOCIAL, HUMAN AND MATHEMATICAL SCIENCES Geography and Environment Volume 1 of 1 Forest ecosystem services for agricultural risk reduction: examining interactions within socio-ecological systems in Madagascar by Radhika Dave Thesis for the degree of Doctor of Philosophy September 2016 UNIVERSITY OF SOUTHAMPTON FACULTY OF SOCIAL, HUMAN AND MATHEMATICAL SCIENCES Geography and Environment Thesis for the degree of Doctor of Philosophy FOREST ECOSYSTEM SERVICES FOR AGRICULTURAL RISK REDUCTION: EXAMINING INTERACTIONS WITHIN SOCIO-ECOLOGICAL SYSTEMS IN MADAGASCAR Radhika Dave ABSTRACT Natural ecosystems like forests, wetlands and coastal habitats are hypothesized to support disaster risk reduction by decreasing the exposure of communities to hazards such as floods, landslides and storm surge. Forest cover loss is thought to increase flood risk and is seen as a primary driver of soil erosion and consequent siltation of irrigation channels and agricultural fields. While there is a growing body of evidence in support of the role of ecosystem processes in providing these hazard mitigation services much of it is site specific, and gaps remain in our understanding of the specific contexts, type of hazards and scenarios in which forest ecosystems play this role. This study contributes new knowledge to this research gap by investigating the question of how smallholder farmers in Madagascar exposed to extreme weather hazards perceive the importance of tropical dry deciduous forests in regulating hazard impacts and supporting agricultural production. In doing so, this thesis first evaluates the evolving trajectories of change in system variables including various provisioning ecosystem services, biophysical, economic and governance indicators, and human wellbeing outcomes during Madagascar’s recent history to provide context and identify patterns at the national scale. It then investigates the problem at the local, sub-catchment scale in a case study setting through household surveys, focus groups and key informant interviews in two communities with opposing forest cover trajectories in northwest Madagascar. This combined methodological approach allows for the linking of local vulnerability to wider system dynamics. The first set of findings demonstrates that the broader systems dynamics show signs of trade-off between increasing crop production, deteriorating natural environment and decreasing human wellbeing, which together with an evident decrease in the level of connectivity between key parameters reflect conditions associated with stagnation and poverty traps. Case study results show a vulnerable smallholder farming population, typically exposed to a set of six hazard impact types during extreme weather events. The type of hazards experienced influences the perception of whether or not forests provide hazard impact mitigation benefits and this is one of thesis’ original contributions to knowledge. Another core finding confirms the importance of tropical dry forests to the lives of smallholder farmers through food and raw materials, and provides new insights on the positive view held by a majority of the participants of hazard mitigation services provided by forest fragments, while also finding that only the income generating services of forest based tourism and honey production predict participation in forest management. This study integrates two normally distinct areas of research – hazard mitigation and forest ecosystem services - to provide new insights on the relevance of forest cover and management to agricultural risk reduction in smallholder, forest-edge farm communities, contributing new knowledge with implications for both forest management and rural development policies. Table of Contents Table of Contents ............................................................................................................ i List of Tables ................................................................................................................ vii List of Figures ................................................................................................................ ix DECLARATION OF AUTHORSHIP ................................................................................... xiii Acknowledgements ...................................................................................................... xv Definitions and Abbreviations ..................................................................................... xvi Chapter 1: Introduction ........................................................................................ 1 1.1 Overview .......................................................................................................... 1 1.2 The case for Madagascar as the study focus ...................................................... 2 1.3 Research Aim and Objectives ............................................................................ 4 1.4 Thesis structure ................................................................................................. 4 Literature Review ................................................................................ 4 Research Design ................................................................................... 5 Substantive Chapters ........................................................................... 5 Conclusions .......................................................................................... 6 Chapter 2: Literature Review ................................................................................ 7 2.1 Introduction ...................................................................................................... 7 2.2 Hazards, Risk and Vulnerability ......................................................................... 7 Hazards and Risk .................................................................................. 7 Vulnerability ........................................................................................ 9 2.3 Risk reduction and ecosystem functions .......................................................... 13 Ecosystem based approaches to DRR ................................................. 14 Mechanisms and examples for ecosystem-based approaches to DRR . 15 Forests and Flood Regulation ............................................................. 20 Paired Catchment Studies – Historical perspective on the relationship between forests and floods ............................................................... 23 Methodological conclusions ............................................................... 25 i 2.4 Land Cover Change – trends and drivers of deforestation in the tropics and in Madagascar .................................................................................................... 26 Deforestation trends .......................................................................... 27 Drivers of deforestation ..................................................................... 31 2.5 Concluding remarks and research gaps ............................................................ 34 Chapter 3: Conceptual background and research methodology ........................... 37 3.1 Introduction .................................................................................................... 37 3.2 Conceptual frameworks .................................................................................. 37 Political Ecology ................................................................................. 37 Ecosystem services framework .......................................................... 38 Complex socio-ecological systems and co-evolutionary dynamics ...... 39 3.3 Rationale for an interdisciplinary research approach ....................................... 39 3.4 Positionality .................................................................................................... 40 3.5 Study Design ................................................................................................... 41 Methodological approaches for understanding trade-offs and system behaviour .......................................................................................... 43 Methodological approaches case study data collection ...................... 44 Chapter 4: Madagascar: