Reorganization without disruption: How fire‐driven spatiotemporal changes in floral resource landscapes influence plant–bee interaction networks

Plants provide important resources for bee pollinators, which rely on different floral‐resource types for distinct ecological demands. Fire rapidly alters vegetation composition, impacting resource availability and plant–pollinator dynamics. However, its effects on floral resource diversity (i.e. the composition of floral resource types) have never been assessed in the tropics, hindering our understanding of how diverse plant–bee interaction networks respond to fire‐triggered changes in floral resource supply.

We assessed flower production, plant species richness and Shannon diversity, and the Shannon diversity and spatiotemporal β ‐diversity of floral resources, following a well‐documented fire event in the Brazilian Cerrado, to evaluate fire's impact on the floral resource landscape. Additionally, we investigated whether changes in floral landscape affected plant–bee networks by inspecting their structure, robustness to plant loss, interaction β ‐diversity, and spatiotemporal organization of pairwise interactions.

At a broader scale, fire neither consistently stimulated flower production nor increased plant species richness or Shannon diversity, including floral resource diversity. However, at both broader and finer scales, fire influenced the spatiotemporal distribution of floral resources, increasing β ‐diversity between the pre‐burned and burned conditions. Plant–bee interactions maintained similar network structure and robustness to plant loss before and after the fire. Nonetheless, increased β ‐diversity in the floral resource landscape promoted by fire increased plant–bee interaction β ‐diversity, leading to more interaction rewiring, turnover and the spatiotemporal reorganization of pairwise interactions.

Fire increased the temporal and spatial availability of floral resources by stimulating flowering in new patches and extending blooming periods, without disrupting plant–bee interaction networks. We argue that bees adapt to fine‐scale shifts in floral resource distribution, preserving interaction network robustness in recurrently burned Cerrado ecosystems. Thus, fine‐scale changes in floral resources do not erode plant–bee network structure or stability. However, dissimilarities in floral resource presentation and plant–bee interactions reveal that fire introduces patchy variability in Cerrado ecosystems.

Synthesis and applications . Contrary to fire suppression policies that promote ecological homogenization, we suggest that patchy prescribed fires could be used to enhance spatiotemporal diversity in the Cerrado by promoting fine‐scale heterogeneity in floral resources and resource‐mediated plant–bee interactions.