Pierre Bommel

Articulating land and water dynamics with urbanization : An attempt to model natural resources management at the urban edge

In a rapidly urbanizing world, population densities no longer allow for unlimited access to safe water. Competition for water, often associated with competition for the access to land, tends to be exacerbated in peri-urban areas. The objective of this paper is to propose a multi-agent model prototype to represent the relationships between urbanization dynamics and land and water management in a peri-urban catchment area. A spatially explicit pilot model was developed using the Cormas platform. This prototype deals with a catchment that is the main drinking water reservoir and spring of a metropolitan area, and is subjected to high urban pressure and problems of pollution connected to land use and rain. The combined use of cellular automata, spatialized passive entities and communicating agents allows the articulation of the connections between hydrological processes (water cycle, pollution), land-use changes and urbanization. However, the representation is based on simplified dynamics and further work is needed to develop a simulation model that could be used as a discussion tool for land and water management at the urban edge.

Participatory Agent-Based Simulation for Renewable Resource Management: The Role of the Cormas Simulation Platform to Nurture a Community of Practice

This paper describes how the Cormas platform has been used for 12 years as an artefact to foster learning about agent-based simulation for renewable resource management. Among the existing generic agent-based simulation platforms, Cormas occupies a tiny, yet lively, place. Thanks to regular training sessions and an electronic forum, a community of users has been gradually established that has enabled a sharing of ideas, practices and knowledge, and the emergence of a genuine community of practice whose members are particularly interested in participatory agent-based simulation.

Models for Sharing Representations

Companion modelling implementation is based on a network of individuals and artefacts amongst which models occupy a special place. This chapter presents the various models developed in a companion modelling process for purposes of representation sharing. Designed as a way of understanding actual (reference) systems in which social and biophysical dynamics overlap, models represent the evolution of these systems and are used for organizing exploratory simulation exercises involving stakeholders in the reference system.

Purpose, processes, partnerships, and products: four Ps to advance participatory socio‐environmental modeling

Including stakeholders in environmental model building and analysis is an increasingly popular approach to understanding ecological change. This is because stakeholders often hold valuable knowledge about socio-environmental dynamics and collaborative forms of modeling produce important boundary objects used to collectively reason about environmental problems. Although the number of participatory modeling (PM) case studies and the number of researchers adopting these approaches has grown in recent years, the lack of standardized reporting and limited reproducibility have prevented PMs establishment and advancement as a cohesive field of study. We suggest a four-dimensional framework (4P) that includes reporting on dimensions of (1) the Purpose for selecting a PM approach (the why); (2) the Process by which the public was involved in model building or evaluation (the how); (3) the Partnerships formed (the who); and (4) the Products that resulted from these efforts (the what). We highlight four case studies that use common PM software-based approaches (fuzzy cognitive mapping, agent-based modeling, system dynamics, and participatory geospatial modeling) to understand human-environment interactions and the consequences of ecological changes, including bushmeat hunting in Tanzania and Cameroon, agricultural production and deforestation in Zambia, and groundwater management in India. We demonstrate how standardizing communication about PM case studies can lead to innovation and new insights about model-based reasoning in support of ecological policy development. We suggest that our 4P framework and reporting approach provides a way for new hypotheses to be identified and tested in the growing field of PM.

Agent-Based Modelling and Simulation Applied to Environmental Management

The purpose of this chapter is to summarize how agent-based modelling and simulation (ABMS) is being used in the area of environmental management. With the science of complex systems now being widely recognized as an appropriate one to tackle the main issues of ecological management, ABMS is emerging as one of the most promising approaches. To avoid any confusion and disbelief about the actual usefulness of ABMS, the objectives of the modelling process have to be unambiguously made explicit. It is still quite common to consider ABMS as mostly useful to deliver recommendations to a lone decision-maker, yet a variety of different purposes have progressively emerged, from gaining understanding through raising awareness, facilitating communication, promoting coordination or mitigating conflicts. Whatever the goal, the description of an agent-based model remains challenging. Some standard protocols have been recently proposed, but still a comprehensive description requires a lot of space, often too much for the maximum length of a paper authorized by a scientific journal. To account for the diversity and the swelling of ABMS in the field of ecological management, a review of recent publications based on a lightened descriptive framework is proposed. The objective of the descriptions is not to allow the replication of the models but rather to characterize the types of spatial representation, the properties of the agents and the features of the scenarios that have been explored and also to mention which simulation platforms were used to implement them (if any). This chapter concludes with a discussion of recurrent questions and stimulating challenges currently faced by ABMS for environmental management.

Cormas: An Agent-Based Simulation Platform for Coupling Human Decisions with Computerized Dynamics

This paper aims at presenting the new functionalities of Cormas, a generic Agent-Based Modeling (ABM) platform dedicated to common-pool resources management. As free software, Cormas is used by an international community of researchers willing to understand the relationships between societies and their environment. It is intended to facilitate the design of ABM as well as the monitoring and analysis of simulation scenarios. To meet the increasing demand of our community of practice, the Cormas development has taken an innovative direction oriented towards the collective design of models and interactive simulation. In accordance with the principles of participatory methods and serious games, many experiments developed with Cormas combine two layers of complexity: the natural dynamic of the system, simulated by the computer, and the stakeholders’ interactions and decisions played by the actors. Between these two extremes, a range of intermediate situations exists where some decisions are human and others are computer-specified. The term hybrid agent simulation covers these intermediary situations. The main idea is to enable the stakeholders to interact with the execution of a simulation by modifying the behavior of the agents and the way they use the resources. Thus, it is possible to collectively explore scenarios to better understand how a desired situation may be reached. This may feed back into the collective design of the model. As our intention is to involve more deeply the stakeholders into the modeling process, it is necessary to have an easily changeable tool to act on the simulation and to modify the conceptual model on the fly. After having explained the purpose and the philosophy of the Companion Modeling, this paper presents how the Cormas functionalities (asymmetry of information, agent manipulation, modification of behavior, stepping back and distributed 1 CIRAD UPR GREEN, France & Universidad de Costa Rica, CIEDA, Costa Rica 2 CNRS UMR 7266 LIENSs, La Rochelle, France 3 CIRAD UPR GREEN, Montpellier, France

A further step towards participatory modelling. Fostering stakeholder involvement in designing models by using executable UML

This paper focuses on the collective design and immediate execution of an agent-based model (ABM) by dynamically interpreting the activity diagrams of agent behaviours. To reach this objective, we have implemented an ABM of livestock producers facing drought conditions in Uruguay. The first step consists in implementing a standard ABM with pasture growth, herd dynamics and simple agents roughly imitating farmers’ strategies. The second step is more participative since it consists in assessing the model with the real cattle farmers. As with most modelling processes, this evaluation phase requires feedback on model design. In order to make this assessment more lively and efficient, we have conceived a tool for drawing diagrams that can be immediately interpreted by the agents. Thanks to this new editor, the actors have quickly understood how the model worked and were able to criticize and modify it. Thus, this innovative modelling tool enables the involvement of stakeholders in co-designing ABM for participatory foresight studies. We hope it will facilitate the emergence of new and more efficient practices for farm management that can account for climate changes.

How do participants view the technologies used in companion modelling .

The companion modelling approach mobilizes a number of tools to establish a representation of a given system.

Tools and methods in participatory modeling: Selecting the right tool for the job

Various tools and methods are used in participatory modelling, at different stages of the process and for different purposes. The diversity of tools and methods can create challenges for stakeholders and modelers when selecting the ones most appropriate for their projects. We offer a systematic overview, assessment, and categorization of methods to assist modelers and stakeholders with their choices and decisions. Most available literature provides little justification or information on the reasons for the use of particular methods or tools in a given study. In most of the cases, it seems that the prior experience and skills of the modelers had a dominant effect on the selection of the methods used. While we have not found any real evidence of this approach being wrong, we do think that putting more thought into the method selection process and choosing the most appropriate method for the project can produce better results. Based on expert opinion and a survey of modelers engaged in participatory processes, we offer practical guidelines to improve decisions about method selection at different stages of the participatory modeling process.

Twelve Questions for the Participatory Modeling Community

Participatory modeling engages the implicit and explicit knowledge of stakeholders to create formalized and shared representations of reality and has evolved into a field of study as well as a practice. Participatory modeling researchers and practitioners who focus specifically on environmental resources met at the National Socio-Environmental Synthesis Center (SESYNC) in Annapolis, Maryland, over the course of 2 years to discuss the state of the field and future directions for participatory modeling. What follows is a description of 12 overarching groups of questions that could guide future inquiry.