Combining participatory approach and modeling to quantify spatial interdependencies in pest control services

Abstract

Reinforcing the regulation of pests by their natural enemies is a promising way of reducing the use of pesticides and can be achieved through the adoption of management options at multiple scales, from field to landscape. In practice, however, most management efforts concentrate on modifying farming practices at the field level and examples of implementation of landscape-scale pest management strategies are scarce. Here, we report on place-based research that combined the co-design of scenarios of landscape-scale changes in farming practices and ex ante evaluation of pest control services under such scenarios, through the development of predictive models mobilizing long-term local data in two contrasting landscape case studies. We found that scenarios of farming change and predictive models of pest control services were site-specific. In both case studies, we show a high degree of spatial interdependency between farmers in the delivery of on-farm pest control services and, more importantly, that a wide adoption of pest control friendly-farming practices in the landscape leads to a win-win situation for each individual farmer. Farms that implemented changes were predicted to increase on-farm pest control services between 2% and 25%, depending on the changes in farming practices and case studies. When changes were implemented more widely at the landscape scale, the gain varied between 12.5% and 20% in farms where changes were implemented and between 9% and 12.5% in farms where no changes in practices were implemented. Additional gains were obtained when neighboring farmers collaborated and adjusted crop allocation on their farm in order to optimize pest control services at the landscape scale. This outcome reinforced the positive attitude of farmers towards the idea of acting collectively to promote pest control services, although such collective management was not perceived as being easy to implement and should be accompanied.