Some theoretical notes on agrobiodiversity: spatial heterogeneity and population interactions Diego Griffon and Maria-Josefina Hernandez Laboratorio de Evolución y Ecología Teórica, Instituto de Zoología y Ecología Tropical, Universidad Central de Venezuela, Caracas, Venezuela ABSTRACT Ecological interactions are fundamental in ecological pest management, and these interactions form networks. The prop- erties of these networks, where interactions of all possible nature (positive, neutral, negative) coexist, are key for manage- ment, but little is known about them. The main reasons for this lack of knowledge are the difficulties in obtaining empirical evidence. These problems may be partially bypassed using a theoretical approach. Here, by means of mathematical mod- els that represent networks of ecological interactions in agroe- cosystems, we characterize some architectural features that promote the self-regulation of population densities in these networks. The results show that the key features are: spatial heterogeneity and a high proportion of positive interactions. KEYWORDS Ecological networks; ecological pest management; agrobiodiversity The entire landscape comes alive, filled with relationships and relationships within relationships. Frank Herbert Introduction Biodiversity and spatial heterogeneity strongly benefit agricultural land- scapes. Among others, these benefits are related to population regulation of organisms that feed on cultivated plants (Duflot et al. 2015; Fahrig et al. 2011; Letourneau et al. 2011; Rusch et al. 2016, 2010; Tscharntke et al. 2002, 2012; Vandermeer 1989). However, there is a need for further theoretical develop- ment to help us understand the processes behind these empirical observa- tions, particularly from a mechanistic point of view. In a very general sense, in the agroecological literature it is proposed that increasing agricultural biodiversity involves an increase in the number of trophic interactions of the ecological community, which in turn promotes the stability of the whole system (Altieri 1983; Altieri and Nicholls 2000, 2004; CONTACT Diego Griffon diego.griffon@ciens.ucv.ve Laboratorio de Evolución y Ecología Teórica, Instituto de Zoología y Ecología Tropical, Universidad Central de Venezuela, Venezuela This article has been republished with minor changes. These changes do not impact the academic content of the article. Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/wjsa. AGROECOLOGY AND SUSTAINABLE FOOD SYSTEMS https://doi.org/10.1080/21683565.2019.1649781 © 2019 Taylor & Francis