From actors to agents in socio-ecological systems models

Abstract

The ecosystem service concept has emphasized the role of people within socio-ecological systems (SESs). In this paper, we review and discuss alternative ways of representing people, their behaviour and decision-making processes in SES models using an agent-based modelling (ABM) approach. We also explore how ABM can be empirically grounded using information from social survey. The capacity for ABM to be generalized beyond case studies represents a crucial next step in modelling SESs, although this comes with considerable intellectual challenges. We propose the notion of human functional types, as an analogy of plant functional types, to support the expansion (scaling) of ABM to larger areas. The expansion of scope also implies the need to represent institutional agents in SES models in order to account for alternative governance structures and policy feedbacks. Further development in the coupling of human-environment systems would contribute considerably to better application and use of the ecosystem service concept.

Modelling feedbacks between human and natural processes in the land system

“…Through model development and integration, knowledge is synthesized, formalized in mathematics or computer code, communicated and discussed among others, and gaps in knowledge and data are identified that create an iterative modelling process (Rounsevell et al 2012). Finally, coupled models will be most useful if we 5 can use them to test possible interventions in the Earth system that might help avoid the worst possible outcomes.…”

Predictive ecology: systems approaches

“…The meeting presupposed the need to consider the ecological impact of anthropogenic environmental changes as a major rationale for the need to make ecological predictions. Clearly, human activity often plays an important role in structuring ecosystems and is frequently a driver of change within ecosystems [40,41]. The exclusion of humans from ecological models seems artificial, and although there are some good examples in which individual-or agent-based models of human populations (agent-based models (ABMs) in the social sciences being essentially similar to individual-based models in ecology) and biosphere models have been successfully coupled to produce predictions about the fate of the ecosystem and consequences to the human population [42], these are unusual.…”

“…The exclusion of humans from ecological models seems artificial, and although there are some good examples in which individual-or agent-based models of human populations (agent-based models (ABMs) in the social sciences being essentially similar to individual-based models in ecology) and biosphere models have been successfully coupled to produce predictions about the fate of the ecosystem and consequences to the human population [42], these are unusual. Agent-based modelling is regarded as an appropriate tool for understanding human decisionmaking and is often used in models of humanenvironment interactions [40,41]. Rounsevell [40] identifies that many of the issues that concern the ecological community about individual-based models (IBMs) are also of concern to social scientists using ABMs of human systems.…”

“…For example, processes need to be scaled both out and up to include larger geographical areas (out-scaling) and to aggregate individuals into groups (up-scaling). These would be familiar problems to people concerned with using IBMs and there may be parallel solutions in, for example, the use of stage-and age-structured approximations to scale out [35] and functional types to scale up [40], although any such approximations would inevitably result in a reduction of individual-level heterogeneity in the model, which if it influenced the outcome in important ways might be of concern [37].…”

“…Human behaviour is frequently the target of policy interventions both by agencies attempting to create their desired conservation outcomes [17,41] and by institutions and governments [40]. The fact that humans often modify their behaviour extremely rapidly in response to an intervention can mean that there are unintended outcomes of well-intentioned interventions; for example, the fact that acquisition of land for nature conservation can impact upon local land prices potentially results in landowners being tempted by higher prices to put additional land on the market leading to a counter-productive effect on biodiversity outside protected areas if this land is then developed [43].…”