Main Agroecological Structure and Landscape Context Shape Insect Biodiversity and Ecosystem Services During Agroecological Transition in Mediterranean Chile

Farm-level ecological organization may influence insect biodiversity, although these relationships can vary among regional settings and may not be captured fully by an aggregated agroecological index. We evaluated associations between the Main Agroecological Structure (MAS), insect biodiversity, community composition, and functional groups associated with potential pollination and biological control across 30 smallholder farms in the Maule Region of Mediterranean Chile. The farms were distributed among Cauquenes, Rauco, and San Clemente, and their immediate surroundings were characterized within 500 m. A total of 3926 individuals representing 144 taxonomic units were collected using standardized yellow pan traps. MAS varied widely among farms (31.8–79.4) but did not differ among municipalities. After accounting for municipality, MAS was not associated with Hill diversity of orders q = 0, q = 1, or q = 2, and no MAS × municipality interaction was detected for these responses. Insect community composition differed among municipalities, although this result was accompanied by heterogeneous multivariate dispersion, whereas the within-municipality association between MAS and community composition was not significant. Pollinator richness and abundance were not associated with MAS. Natural-enemy richness showed a MAS × municipality interaction, with positive associations in Cauquenes and San Clemente but not in Rauco. Natural-enemy abundance increased with MAS, although residual spatial autocorrelation remained after spatial sensitivity analysis. These results indicate that MAS is useful for characterizing farm agroecological organization but was not a general predictor of insect biodiversity. Regional setting, individual MAS components, and the immediate surroundings of each farm should therefore be distinguished when evaluating biodiversity and ecosystem-service potential.