IntELiMon: an automated framework for standardized terrestrial lidar processing in multi-disciplinary ecosystem monitoring

Abstract Terrestrial laser scanning (TLS) enables rapid, objective, and repeatable measurement of 3D forest and shrubland structure, but operational use is often limited by complex, multi-stage processing workflows. IntELiMon (Interagency Ecosystem lidar Monitoring) is a flexible, automated processing system that streamlines TLS-based monitoring by reducing manual processing and applying consistent quality assurance and reproducible analyses. The current implementation supports data collected with Leica BLK360 G1 and G2 sensors, ingested in PTX file format and processed within a custom framework, which manages data flow, workflow orchestration, and automated quality checks across projects and sites. Standard point cloud preprocessing steps, including registration, filtering, ground normalization, and noise reduction, are followed by initial structural analyses that derive core metrics describing vegetation height, density, and spatial pattern of points. IntELiMon then applies semantic segmentation of trees and shrubs to isolate vegetation elements and utilizes custom structural and geometric analyses for forest, shrubland, and grassland monitoring applications, which feed into a configurable modeling engine supporting custom fuel modeling and predictive relationships using lightweight machine learning approaches. Outputs are delivered through the IntELiMon online viewer, providing interactive access to raster products, tree and shrub inventories, and structural metric files, while programmatic access through the IntELiMon application programming interface (API) enables external applications and services to query TLS-derived products, incorporate them into broader fire and fuel modeling workflows, and update results with operational decision-support systems.