Low-Cost and Mobile Lidar Technologies for Forest Inventory: A Review on Accuracy, Efficiency, and Multi-Temporal Monitoring Potential

Abstract

Accurate information on forest structure is essential for sustainable forest management, carbon accounting, and ecosystem monitoring. Traditional field-based forest inventory methods are labour-intensive, time-consuming, and have low temporal resolution. Advances in technology (specifically, Light Detection and Ranging, or LiDAR) – specifically, mobile and low-cost systems of LiDAR - present new opportunities to conduct forest measurements with greater efficiency and repeatability. This study employs a systematic literature review of the application of mobile and consumer-grade LiDAR technology for conducting inventory of forests, with a focus on their accuracy and effectiveness in quantifying key dendrometric variables and their capacity as tools for multi-temporal monitoring. The literature search utilised the PRISMA 2020 framework and was conducted using the PECO framework, identifying studies published between 2015 and 2026. The results show that mobile LiDAR systems, including handheld and smartphone-based systems, can be used to obtain reliable estimates of relevant dendrometric attributes, particularly DBH, under appropriate conditions. Additionally, these technologies improve data collection efficiency in comparison to traditional forest inventory methods; however, they still have limitations regarding the estimation of total tree height due to canopy obstructing measurements and the inability of sensors to measure tree height. The performance of measurement is affected by environmental and operational factors such as seasonal conditions, the density of point clouds, the characteristics of species, and the strategies used to scan. Potentially, the analysis of point clouds over multiple time periods can be used to detect changes in structure; however, the reliability of the analysis is dependent upon data quality and accurate registration relative to one another. Overall, mobile laser scanning with LiDAR is a promising alternative to traditional inventory methods in forestry.