Chapter Four - Promoting crop pest control by plant diversification in agricultural landscapes: A conceptual framework for analysing feedback loops between agro-ecological and socio-economic effects.

Given the negative environmental effects of conventional agricultural techniques, the need for biodiversity-friendly agriculture systems that rely more on ecosystem services and less on chemical inputs is becoming increasingly urgent. In this paper, we focus on crop protection strategies that are alternatives to the use of pesticides. Diversification of the plant component of agricultural areas at different space and time scales has been presented as a powerful socio-economic and agro-ecological mechanism for the sustainable control of pests. Our interdisciplinary group of scientific experts examined the literature on the ecological effects of plant diversification on pests and their natural enemies, as well as the social science literature on the conditions for farmers to adopt the corresponding practices, to assess the potential offered by plant diversification. We developed a conceptual framework that connects the agro-ecological and socio-economic components of an agricultural landscape in a dynamic loop accounting for interactions among elements at different spatial and temporal scales and their feedback effects. This article presents this framework and illustrates its application to the case of wheat production and protection. By explicitly connecting each level of agro-ecological organization with the potential socio-economic drivers and limitations underpinning the adoption and implementation of plant diversification in landscapes, this framework makes it possible to analyse the synergies and antagonisms between different modes of diversification and the conditions of their deployment. Exploring this framework is a prerequisite to the identification of opportunities and key feed-back loops for designing diversification strategies that unlock the agro-ecological potential of future production systems. We conclude that there is a need for interdisciplinary research in experimental landscapes involving farmers and other local stakeholders to design sustainable future agricultural landscapes that deliver high levels of biological control services. [ABSTRACT FROM AUTHOR]