Flows in Agro-food Networks (FAN): An agent-based model to simulate local agricultural material flows

Abstract

Agro-food networks are characterized by complex material exchanges among farms, processors, consumers, and waste managers involved in fertilization, food, feed and bioenergy production. Better coordination of material exchanges at the local scale can facilitate more efficient resource use. Here, we present a new agent-based model, "Flows in Agro-food Networks" (FAN), which simulates the processing and exchange of fertilizers, feed, food and wastes among farms and multiple upstream or downstream partners (feed and fertilizer suppliers, food industries, waste processors, and anaerobic digesters) in small farming regions. FAN includes a series of environmental indicators that can be used to assess alternative scenarios in terms of ecosystem services, nutrient cycling, and resource autonomy. We use a French case study to demonstrate FAN's dynamics and to explore the sensitivity of key parameters. We show a strong influence of spatial distance between agents, their disposition to exchange, and their preference for specific materials on local agro-food network simulations. FAN is powerful theoretical tool to explore and assess opportunities for a circular economy in small farming regions and to unravel interactions between recycling, environmental performance and food production.

Co-benefits and Trade-Offs From Agro-Food System Redesign for Circularity: A Case Study With the FAN Agent-Based Model

“…Despite the insights provided by our analysis, a key limitation is that no economic cost calculations are implemented, in part due to the fact that monetary values could change depending on public subsidies, such as those existing for biogas production in many countries (Börjesson and Ahlgren, 2012;Sun et al, 2014;Appel et al, 2016). In FAN simulations, however, economic data is implicit in the mechanisms underlying the exchanges even though there is no actual cost analysis, as discussed in more detail by Fernandez-Mena et al (2019). We assumed that for implementing these practices and innovations famers will need support by public and engagement of private institutions.…”

“…At this scale, FAN may help to unravel interactions concerning material exchanges in farming activities by simulating recycling flows and assessing their degree of circularity. The FAN model mechanisms and submodels are described following the ODD (Overview, Design concepts, and Details) protocol for agent-based models in Fernandez-Mena et al (2019). The model script, the Ribéracois dataset and the scenarios parametrization are available in Fernandez-Mena (2017a).…”

“…We hypothesized that greater environmental benefits would accrue in scenarios that require more profound agro-food system changes (i.e., for "Redesign-like" scenarios). The scenarios are built in the FAN model by changing specific parameters and coefficients of the model (Table 2), as detailed in Fernandez-Mena et al (2019). A brief scenario description is given as follows: S1.…”

“…Note that even if crop production is lower in the scenario without chemical fertilizers, FAN assumes that livestock in Ribéracois are fed in priority to crop food transformation, and when needed, by importing external feed and forage to meet animal minimum requirements (Fernandez-Mena et al, 2019).…”

Analysis of urban agriculture solid waste in the frame of circular economy: Case study of tomato crop in integrated rooftop greenhouse

“…Most are based on the compost elaboration and the recovery of its nutrients and compounds, elaborating high value biochemicals (Brar et al,2014) or finally as energy, considering the large volumes of waste that are generated. From the CE perspective, initiatives with a social vision have emerged focused on the exchange of waste at the district level for its use (Fernandez-Mena et al, 2020). On the other hand, the material valorization of residual biomass from the agricultural industry has expanded due to the interest in creating new eco-J o u r n a l P r e -p r o o f materials with it.…”