Journal Article

Permanent link for this collectionhttps://hdl.handle.net/10535/5

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Adaptation and Sustainability in a Small Arctic Community: Results of an Agent-Based Simulation Model
(2004) Berman, Matthew; Nicolson, Craig; Kofinas, Gary P.; Tetlichi, Joe; Martin, Stephanie
"Climate warming and resource development could alter key Arctic ecosystem functions that support fish and wildlife resources harvested by local indigenous communities. A different set of global forces--government policies and tourism markets--increasingly directs local cash economies that communities use to support subsistence activities. Agent-based computational models (ABMs) contribute to an integrated assessment of community sustainability by simulating how people interact with each other and adapt to changing economic and environmental conditions. Relying on research and local knowledge to provide rules and parameters for individual and collective decision making, our ABM generates hypothetical social histories as adaptations to scenario-driven changes in environmental and economic conditions. The model generates projections for wage employment, cash income, subsistence harvests, and demographic change over four decades based on a set of user-defined scenarios for climate change, subsistence resources, development, and government spending. Model outcomes assess how scenarios associated with economic and climate change might affect the local economy, resource harvests, and the well-being of residents for the Western Arctic Canadian community of Old Crow, Yukon. The economic and demographic outcomes suggest implications for less quantifiable social and cultural changes. The model can serve as a discussion tool for a fuller exploration of community sustainability and adaptation issues."
Agent-based Analysis of Agricultural Policies: an Illustration of the Agricultural Policy Simulator AgriPoliS, its Adaptation and Behavior
(2006) Happe, Kathrin; Kellerman, Konrad; Balmann, Alfons
"This paper combines agent-based modeling of structural change with agricultural policy analysis. Using the agent-based model AgriPoliS, we investigate the impact of a regime switch in agricultural policy on structural change under various framework conditions. Instead of first doing a sensitivity analysis to analyze the properties of our model and then examining the introduced policy in an isolated manner, we use a meta-modeling approach in combination with the statistical technique of Design of Experiments to systematically analyze the relationship between policy change and model assumptions regarding key determinants of structural change such as interest rates, managerial abilities, and technical change. As a result, we observe that the effects of policies are quite sensitive to the mentioned properties. We conclude that an isolated analysis of a policy regime switch would be of only minor value for policy advice given the ability of simulation models to examine various potential futures."
Agents, Individuals, and Networks: Modeling Methods to Inform Natural Resource Management in Regional Landscapes
(2012) Parrott, Lael; Chion, Clément; Gonzaléz, Rodolphe; Latombe, Guillaume
"Landscapes are complex systems. Landscape dynamics are the result of multiple interacting biophysical and socioeconomic processes that are linked across a broad range of spatial, temporal, and organizational scales. Understanding and describing landscape dynamics poses enormous challenges and demands the use of new multiscale approaches to modeling. In this synthesis article, we present three regional systems--i.e., a forest system, a marine system, and an agricultural system--and describe how hybrid, bottom-up modeling of these systems can be used to represent linkages across scales and between subsystems. Through the use of these three examples, we describe how modeling can be used to simulate emergent system responses to different conservation policy and management scenarios from the bottom up, thereby increasing our understanding of important drivers and feedback loops within a landscape. The first case study involves the use of an individual-based modeling approach to simulate the effects of forest harvesting on the movement patterns of large mammals in Canada's boreal forest and the resulting emergent population dynamics. This model is being used to inform forest harvesting and management guidelines. The second case study combines individual and agent-based approaches to simulate the dynamics of individual boats and whales in a marine park. This model is being used to inform decision-makers on how to mitigate the impacts of maritime traffic on whales in the Saint Lawrence Estuary in eastern Canada. The third example is a case study of biodiversity conservation efforts on the Eyre Peninsula, South Australia. In this example, the social-ecological system is represented as a complex network of interacting components. Methods of network analysis can be used to explore the emergent responses of the system to changes in the network structure or configuration, thus informing managers about the resilience of the system. These three examples illustrate how bottom-up modeling approaches may contribute to a new landscape science based on scenario building, to find solutions that meet the multiple objectives of integrated resource management in social-ecological systems."
Coordination in Irrigation Systems: An Analysis of the Lansing-Kremer Model of Bali
(2007) Janssen, Marco A.
"Farmers within irrigation systems, such as those in Bali, solve complex coordination problems to allocate water and control pests. Lansing and Kremer's [Lansing, J.S., Kremer, J.N., 1993. Emergent properties of Balinese water temples. American Anthropologist 95(1), 97-114] study of Balinese water temples showed that this coordination problem can be solved by assuming simple local rules for how individual communities make their decisions. Using the original Lansing-Kremer model, the robustness of their insights was analyzed and the ability of agents to self-organize was found to be sensitive to pest dynamics and assumptions of agent decision making."
Empirically Based, Agent-based Models
(2006) Janssen, Marco A.; Ostrom, Elinor
"There is an increasing drive to combine agent-based models with empirical methods. An overview is provided of the various empirical methods that are used for different kinds of questions. Four categories of empirical approaches are identified in which agent-based models have been empirically tested: case studies, stylized facts, role-playing games, and laboratory experiments. We discuss how these different types of empirical studies can be combined. The various ways empirical techniques are used illustrate the main challenges of contemporary social sciences: (1) how to develop models that are generalizable and still applicable in specific cases, and (2) how to scale up the processes of interactions of a few agents to interactions among many agents."
Encouraging Sustainable Transport Choices in American Households: Results from an Empirically Grounded Agent-Based Model
(2014) Natalini, Davide; Bravo, Giangiacomo
"The transport sector needs to go through an extended process of decarbonisation to counter the threat of climate change. Unfortunately, the International Energy Agency forecasts an enormous growth in the number of cars and greenhouse gas emissions by 2050. Two issues can thus be identified: (1) the need for a new methodology that could evaluate the policy performances ex-ante and (2) the need for more effective policies. To help address these issues, we developed an Agent-Based Model called Mobility USA aimed at: (1) testing whether this could be an effective approach in analysing ex-ante policy implementation in the transport sector; and (2) evaluating the effects of alternative policy scenarios on commuting behaviours in the USA. Particularly, we tested the effects of two sets of policies, namely market-based and preference-change ones. The model results suggest that this type of agent-based approach will provide a useful tool for testing policy interventions and their effectiveness."
Environmental Licensing and Land Aggregation: An Agent-Based Approach to Understanding Ranching and Land Use in Rural Rondônia
(2011) Bell, Andrew Reid
"Agricultural development and climate change will be two of the major stressors on the Amazon natural-human system in the decades to come. Environmental licensing for rural properties is being implemented in several states in the Brazilian Amazon with the goal of restoring forests in agricultural landscapes and mediating the impacts of these stressors. This study presents an agent-based model of ranching and land exchange, informs it with empirical results from social research in the Ji-Paraná River Basin, Rondônia, Brazil, and investigates the social, economic, and environmental outcomes that can be expected as a result of environmental licensing in the context of climate change. Model results informed by these data suggest that although an environmental licensing scheme with monitoring and enforcement may increase the level of forested land in ranching landscapes, it may do so at the expense of the small producer. To the extent that effective monitoring and enforcement exist, a focus on larger holdings will help to mediate this negative social impact. These results suggest that a middle ground can be found in cases where current environmental goals conflict with legacies of past colonization and resource-use regimes."
Examining Fire-Prone Forest Landscapes as Coupled Human and Natural Systems
(2014) Spies, Thomas A.; White, Eric M.; Kline, Jeffret D.; Fischer, Paige A.; Ager, Alan; Bailey, John; Bolte, John; Koch, Jennifer; Platt, Emily; Olsen, Christine S.; Jacobs, Derric; Shindler, Bruce; Steen-Adams, Michelle M.; Hammer, Roger
"Fire-prone landscapes are not well studied as coupled human and natural systems (CHANS) and present many challenges for understanding and promoting adaptive behaviors and institutions. Here, we explore how heterogeneity, feedbacks, and external drivers in this type of natural hazard system can lead to complexity and can limit the development of more adaptive approaches to policy and management. Institutions and social networks can counter these limitations and promote adaptation. We also develop a conceptual model that includes a robust characterization of social subsystems for a fire-prone landscape in Oregon and describe how we are building an agent-based model to promote understanding of this social-ecological system. Our agent-based model, which incorporates existing ecological models of vegetation and fire and is based on empirical studies of landowner decision-making, will be used to explore alternative management and fire scenarios with land managers and various public entities. We expect that the development of CHANS frameworks and the application of a simulation model in a collaborative setting will facilitate the development of more effective policies and practices for fire-prone landscapes."
Modelling Evolving Rules for the Use of Common-Pool Resources in an Agent-Based Model
(2007) Smajgl, Alexander
"Institutional arrangements are key drivers of the use of common-pool resources (CPR). The analysis of existing arrangements requires a framework that allows research to describe a case study systematically and diagnose the institutional setting. Based on a sound understanding of current institutions the question of what effects alternate arrangements would have becomes evident. This step requires a predictive model, which can either be qualitative or, preferably, analyses an empirical case quantitatively. A major conceptual challenge of a quantitative model is the evolution of rules, which define the boundaries for the agents to choose strategies. This paper develops the conceptual foundations for such a modelling approach and an agent-based model for the analysis of institutional arrangements in a CPR setting."
Population Aggregation in Ancient Arid Environments
(2010) Janssen, Marco A.
"Human societies have adapted to spatial and temporal variability, such as that found in the prehistoric American Southwest. A question remains as to what the implications are of different social adaptations to long-term vulnerability of small-scale human societies. A stylized agent-based model is presented that captures small-group decision making on movements and resource use in ancient arid environments. The impact of various assumptions concerning storage, exchange, sharing, and migration on indicators of aggregation and sustainability are explored. Climate variability is found to increase the resilience of population levels at the system level. Variability reduces the time a population stays in one location and can degrade the soils. In addition to climate variability, the long-term population dynamics is mainly driven by the level of storage and the decision rules governing when to migrate and with whom to exchange."
Risk, Networks, and Ecological Explanations for the Emergence of Cooperation in Commons Governance
(2012) Henry, Adam Douglas; Vollan, Björn
"The commons literature increasingly recognizes the importance of contextual factors in driving collaboration in governance systems. Of particular interest are the ways in which the attributes of a resource system influence the dynamics of cooperation. While this may occur through many pathways, we investigate the mechanisms by which ecological factors influence both the risk of cooperation as well as the density of networks in which strategic interactions take place. Both of these factors influence the co-evolutionary dynamics of network structure and cooperative behavior. These dynamics are investigated through agent-based simulations, which provide preliminary evidence that: 1) low-density networks support higher levels of cooperation, even in high-risk Prisoners Dilemma scenarios; and 2) in high-risk scenarios, networks that develop higher levels of clustering generally enjoy higher societal gains."
Spatial Complexity, Resilience, and Policy Diversity: Fishing on Lake-Rich Landscapes
(2004) Carpenter, Stephen; Brock, William A.
"The dynamics of and policies governing spatially coupled social-ecological mosaics are considered for the case of fisheries in a lake district. A microeconomic model of households addresses agent decisions at three hierarchic levels: (1) selection of the lake district from among a larger set of alternative places to live or visit, (2) selection of a base location within the lake district, and (3) selection of a portfolio of ecosystem services to use. Ecosystem services are represented by dynamics of fish production subject to multiple stable domains and trophic cascades. Policy calculations show that optimal policies will be highly heterogeneous in space and fluid in time. The diversity of possible outcomes is illustrated by simulations for a hypothetical lake district based loosely on the Northern Highlands of the State of Wisconsin. Lake districts are frequently managed as if lakes were independent, similar, endogenously regulating systems. Our findings contradict that view. One-size-fits-all (OSFA) policies erode ecological and social resilience. If regulations are too stringent, social resilience declines because of the potential rewards of overharvesting. If regulations are too lax, ecological resilience is diminished by overharvesting in some lakes. In either case, local collapses of fish populations evoke spatial shifts of angling effort that can lead to serial collapses in neighboring fisheries and degraded fisheries in most or all of the lakes. Under OSFA management, the natural resources of the entire landscape become more vulnerable to transformation because of changes in, e.g., human population, the demand for resources, or fish harvesting technology. Multiplicity of management regimes can increase the ecological resilience, social resilience, and inclusive value of a spatially heterogeneous social-ecological system. Because of the complex interactions of mobile people and multistable ecosystems, management regimes must also be flexible over time. A rights-based scheme may facilitate policy regimes with appropriate spatial patterns and intertemporal fluidity. In lake fisheries, habitat protection adds an important dimension to policy design. Habitat is a slowly changing variable that creates ecological resilience and thereby provides managers with a broader range of options."
The Tragedy of the Park: An Agent-based Model of Endogenous and Exogenous Institutions for Forest Management
(2014) Vallino, Elena
"Many scholars of common-pool resources have found that institutions might solve the tragedy of the commons. I address a particular situation of natural resource management: that of a protected area. In this situation, interests differ. Local rural inhabitants care about the quality of their environment but also need to exploit the resources for livelihood reasons. An external entity such as the State, a donor, an NGO, or some combination thereof decides that there is a need for nature conservation in that area. Because of some evidence of failure for a strictly top-down conservationist approach, the external entity decides to apply the concept of participatory conservation: the local inhabitants become stakeholders in the management of the area and become collectively responsible for conservation, with rights to exploit the resources up to some degree. I argue that project designers try to find a solution to nature conservation through the creation of a situation of a commons: creating a community that has rights and duties toward a particular natural area that is endowed with some resources. Many scholars rely mostly on institutions that are endogenously created within the users’ community to avoid the tragedy of the commons. However, what happens if institutions are imposed? In participatory conservation initiatives, the community has collective rights over the resources, and in this sense, the issue of endogenous rules for the commons management is relevant. However, the level to which the community should exploit the resource is usually imposed by the external project designers. Using agent-based simulations, I develop a theoretical model to look at the consequences of an imposed institution on the state of a forest and on the users’ profit, taking into account the possibilities of violating the imposed rules and facing enforcement. I compare the consequences of this imposed institution with those deriving from an endogenously created institution. I also analyze the interaction between the different kinds of institutions and the individual perceptions of each agent. Many results of the model confirm the quantitative and qualitative findings of the literature: the presence of institutions and enforcement improve the management of the resource with respect to an open-access situation, with different degree of success depending on the kind of institution in place. The two main counterintuitive findings are the following. First, an exogenous institution imposed by external agents may crowd out agents’ intrinsic environmental motivations. Second, when an imposed exogenous institution is in place, the most effective rule is one allowing a sufficient degree of access to resources for the agents, provided that adequate rule enforcement is implemented."
Using Coupled Simulation Models to Link Pastoral Decision Making and Ecosystem Services
(2011) Boone, Randall B.; Galvin, Kathleen A.; BurnSilver, Shauna B.; Thornton, Philip; Oijma, Dennis S.; Jawson, Jacob R.
"Historically, pastoral people were able to more freely use the services their semi-arid and arid ecosystems provide, and they adapted to changes in ways that improved their well-being. More recently, their ability to adapt has been constrained due to changes from within and from outside their communities. To compare possible responses by pastoral communities, we modeled ecosystem services and tied those services to decisions that people make at the household level. We created an agent-based household model called DECUMA, joined that model with the ecosystem model SAVANNA, and applied the linked models to southeastern Kajiado District, Kenya. The structure of the new agent-based model and linkages between the models are described, and then we demonstrate the model results using a scenario that shows changes in Maasai well-being in response to drought. We then explore two additional but related scenarios, quantifying household well-being if access to a grazing reserve is lost and if access is lost but those most affected are compensated. In the second scenario, households in group ranches abutting the grazing reserve that lost access had large declines in livestock populations, less food energy from animal sources, increased livestock sales and grain purchases, and increased need for supplemental foods. Households in more distant areas showed no changes or had increases in livestock populations because their herds had fewer animals with which to compete for forage. When households neighboring the grazing reserve were compensated for the lease of the lands they had used, they prospered. We describe some benefits and limitations of the agent-based approach."

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