Unraveling Forest Complexity: Resource Use Efficiency, Disturbance, and the Structure‐Function Relationship

Structurally complex forests optimize resources to assimilate carbon more effectively, leading higher productivity. Information obtained from Light Detection and Ranging (LiDAR)-derived canopy structural complexity (CSC) metrics across spatial scales serves as a powerful indicator of ecosystem-scale functions such gross primary productivity (GPP). However, our understanding mechanistic links between forest structure function, the impact disturbance on relationship, is limited. Here, we paired eddy covariance measurements water fluxes nine forested sites within 10 × km CHEESEHEAD19 study domain in Northern Wisconsin, USA with drone LiDAR CSC establish which were strong drivers GPP, tested potential mediators relationship. Mechanistic relationships inspected at five resolutions (0.25, 2, 10, 25, 50 m) determine whether persisted scale. Vertical heterogeneity most influential predicting for significant degree management, type, species composition. included structure-function relationship well driver strength was dependent metric calculation resolution. The mediated by light use efficiency (LUE) (WUE), WUE being stronger mediator GPP. These findings allow us improve representation ecosystem models how impacts water-sensitive processes, ultimately Improved enhance capacity accurately simulate responses furthering ability assess climate mitigation strategies.