Browsing by Author "Fraser, Evan D.G."

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Anticipating Vulnerability to Climate Change in Dryland Pastoral Systems: Using Dynamic Systems Models for the Kalahari
(2010) Dougill, Andrew J.; Fraser, Evan D.G.; Reed, Mark
"It is vitally important to identify agroecosystems that may cease functioning because of changing climate or land degradation. However, identifying such systems is confounded on both conceptual and methodological grounds, especially in systems that are moving toward thresholds, a common trait of dryland environments. This study explores these challenges by analyzing how a range of external pressures affect the vulnerability of dryland pastoral systems in the Kalahari. This is achieved by employing dynamic systems modeling approaches to understand the pathways by which communities became vulnerable to drought. Specifically, we evaluate how external pressures have changed: (1) different agroecosystems' abilities to tolerate drought, i.e., ecosystem resilience; (2) rural communities’ abilities to adapt to drought, mediated via their access to assets; and (3) the ability of institutions and policy interventions to play a role in mediating drought-related crises, i.e., socio-political governance. This is done by reanalyzing ecological and participatory research findings along with farm-scale livestock offtake data from across the Kalahari in Botswana. An iterative process was followed to establish narratives exploring how external drivers led to changes in agroecosystem resilience, access to assets, and the institutional capacity to buffer the system. We use 'causal loop diagrams' and statistical dynamic system models to express key quantitative relationships and establish future scenarios to help define where uncertainties lie by showing where the system is most sensitive to change. We highlight how that greater sharing of land management knowledge and practices between private and communal land managers can provide ‘win-win-win’ benefits of reducing system vulnerability, increasing economic income, and building social capital. We use future scenario analyses to identify key areas for future studies of climate change adaptation across the Kalahari."
Assessing Vulnerability to Climate Change in Dryland Livelihood Systems: Conceptual Challenges and Interdisciplinary Solutions
(2011) Fraser, Evan D.G.; Dougill, Andrew J.; Hubacek, Klaus; Quinn, Claire H.; Sendzimir, Jan; Termansen, Mette
"Over 40% of the earths land surface are drylands that are home to approximately 2.5 billion people. Livelihood sustainability in drylands is threatened by a complex and interrelated range of social, economic, political, and environmental changes that present significant challenges to researchers, policy makers, and, above all, rural land users. Dynamic ecological and environmental change models suggest that climate change induced drought events may push dryland systems to cross biophysical thresholds, causing a long-term drop in agricultural productivity. Therefore, research is needed to explore how development strategies and other socioeconomic changes help livelihoods become more resilient and robust at a time of growing climatic risk and uncertainty. As a result, the overarching goal of this special feature is to conduct a structured comparison of how livelihood systems in different dryland regions are affected by drought, thereby making methodological, empirical, and theoretical contributions to our understanding of how these types of social-ecological systems may be vulnerable to climate change. In introducing these issues, the purpose of this editorial is to provide an overview of the two main intellectual challenges of this work, namely: (1) how to conceptualize vulnerability to climate change in coupled social-ecological systems; and (2) the methodological challenges of anticipating trends in vulnerability in dynamic environments."
Climate Science, Development Practice, and Policy Interactions in Dryland Agroecological Systems
(2011) Twyman, Chasca; Fraser, Evan D.G.; Stringer, Lindsay C.; Quinn, Claire H.; Dougill, Andrew J.; Ravera, Federica; Crane, Todd A.; Sallu, Susannah M.
"The literature on drought, livelihoods, and poverty suggests that dryland residents are especially vulnerable to climate change. However, assessing this vulnerability and sharing lessons between dryland communities on how to reduce vulnerability has proven difficult because of multiple definitions of vulnerability, complexities in quantification, and the temporal and spatial variability inherent in dryland agroecological systems. In this closing editorial, we review how we have addressed these challenges through a series of structured, multiscale, and interdisciplinary vulnerability assessment case studies from drylands in West Africa, southern Africa, Mediterranean Europe, Asia, and Latin America. These case studies adopt a common vulnerability framework but employ different approaches to measuring and assessing vulnerability. By comparing methods and results across these cases, we draw out the following key lessons: (1) Our studies show the utility of using consistent conceptual frameworks for vulnerability assessments even when quite different methodological approaches are taken; (2) Utilizing narratives and scenarios to capture the dynamics of dryland agroecological systems shows that vulnerability to climate change may depend more on access to financial, political, and institutional assets than to exposure to environmental change; (3) Our analysis shows that although the results of quantitative models seem authoritative, they may be treated too literally as predictions of the future by policy makers looking for evidence to support different strategies. In conclusion, we acknowledge there is a healthy tension between bottom-up/qualitative/place-based approaches and top-down/quantitative/generalizable approaches, and we encourage researchers from different disciplines with different disciplinary languages, to talk, collaborate, and engage effectively with each other and with stakeholders at all levels."
Social Vulnerability and Ecological Fragility: Building Bridges Between Social and Natural Sciences Using the Irish Potato Famine as a Case Study
(2003) Fraser, Evan D.G.
"Between 1845 and 1850, a potato blight triggered a famine that killed or displaced 25% of the Irish population. Aside from its historical and cultural significance, the Irish Potato Famine illustrates how social and economic forces can create vulnerability to environmental disturbance. Therefore, studying the famine contributes to the on-going academic debate on theories to combine social and environmental data. This paper explores the conditions leading to the Irish famine using the 'Entitlement' framework of Sen (1980) and the 'Panarchy' model proposed by Gunderson and Holling (2002). Entitlement theory allows us to better understand how community food security may become vulnerable over time as different social and economic forces eliminate or restrict avenues to obtain food. In Ireland, a host of economic, demographic, and social pressures marked the decades leading to the famine and meant that the Irish peasantry had no food options when the potato crop failed. Panarchy provides a way of characterizing ecological systems that are vulnerable to disruptions. The agro-ecosystem that developed in Ireland prior to the famine had characteristics typical of vulnerable environments: fields were close together, biodiversity was low, and a large amount of biomass made this ecosystem attractive to opportunistic pests. Neither framework, however, provides an adequate way of examining the totality of human-environmental relations. By combining entitlements with panarchy, we can explore both the social and environmental characteristics of vulnerability. Entitlements and panarchy can be coupled by first assessing the extent to which communities depend on the natural environment for livelihoods, and the options available if the environment changes. Once a dependency on the environment has been ascertained, the characteristics of the specific ecosystems in question must then be assessed to determine their vulnerability to external shocks and disturbances. The panarchy framework makes this possible."
Socioeconomics, Policy, or Climate Change: What is Driving Vulnerability in Southern Portugal?
(2011) Costa, María A. Máñez; Moors, Eddy J.; Fraser, Evan D.G.
"Although climate change models project that communities in southern Europe may be exposed to increasing drought in coming years, relatively little is known about how socioeconomic factors will exacerbate or reduce this problem. We assess how socioeconomic and policy changes have affected drought vulnerability in the Alentejo region of southern Portugal, where EU agricultural policy and the construction of a major dam have resulted in a shift from a land-extensive mixed agricultural system to the intensive production of irrigated grapes and olives. Following a dynamic systems approach, we use both published socioeconomic data and stakeholder interviews to present a narrative account of how this transition has increased the regions vulnerability to drought. To explore the assumptions made in the narrative, and to present different possible future scenarios, we create a dynamic systems model, the results of which suggest that socioeconomic drivers will play a more important role than projected rainfall changes in increasing vulnerability in the future."