The doctoral dissertation in the field of Forest Science will be examined at the Faculty of Science, Forestry and Technology, Joensuu campus.
What is the topic of your doctoral research? Why is it important to study the topic?
Research focuses on assessing forest structural complexity in boreal forests using laser scanning technologies such as airborne laser scanning (ALS) and terrestrial laser scanning (TLS). The research investigates how different laser scanning methods, point cloud densities, and analysis approaches capture forest structure and how reliably they detect structural changes over time.
The topic is important because forest structural complexity strongly influences biodiversity, habitat availability, carbon storage, and overall ecosystem resilience. Changes in forest structure affect species diversity, ecological processes, and the capacity of forests to respond to disturbances and climate change.
Accurate monitoring of structural characteristics enables scientists and forest managers to better understand forest development, assess the impacts of natural disturbances and management practices, and make informed decisions for sustainable forest management.
What are the key findings or observations of your doctoral research?
Key findings of my doctoral research show that laser scanning technologies can reliably monitor changes in forest structural complexity over time. The studies demonstrate that even low-density airborne laser scanning data can detect meaningful structural development in boreal forests, enabling large-scale ecological monitoring using national datasets.
The research also shows that different laser scanning methods capture forest structure differently, highlighting which metrics are most consistent and reliable across technologies. A key contribution is identifying robust indicators for long-term monitoring of forest structural complexity. These findings support improved forest monitoring, biodiversity assessment, and sustainable forest management, while advancing the use of remote sensing for understanding forest ecosystem dynamics.
How can the results of your doctoral research be utilised in practice?
The results of my doctoral research can be applied in practical forest monitoring, management, and biodiversity assessment. The findings help identify reliable laser scanning metrics that can be used to monitor forest structural complexity over time using national airborne laser scanning data. This enables cost-efficient, large-scale monitoring of forest development, habitat quality, and ecosystem resilience.
The methods can support forest inventories, biodiversity conservation planning, and climate-related carbon assessments, while also improving the integration of remote sensing technologies into sustainable forest management and policy decision-making.
What are the key research methods and materials used in your doctoral research?
My doctoral research uses laser scanning–based remote sensing methods to analyze forest structural complexity in boreal forests. The study combines airborne laser scanning (ALS) and terrestrial laser scanning (TLS) datasets collected from research plots in southern Finland at multiple time points. These technologies produce three-dimensional point clouds that describe the spatial arrangement of trees and vegetation.
The research process includes point cloud preprocessing, normalization, and segmentation of individual trees, followed by the calculation of structural complexity metrics describing vertical, horizontal, and volumetric forest structure (e.g., canopy height variability, gap fraction, Shannon entropy, and voxel-based vegetation occupancy). Statistical analyses and cross-sensor comparisons are then used to evaluate how different laser scanning technologies, point densities, and processing approaches capture structural complexity and its development over time.
The doctoral dissertation of Reinis Cimdins, MSc, entitled Boreal forest structural complexity assessments with laser scanning will be examined at the Faculty of Science, Forestry and Technology, Joensuu campus. The opponent will be Professor Ruben Valbuena, Swedish University of Agricultural Sciences, and the custos will be Associate Professor Ville Kankare, University of Turku. Language of the public defence is English.
For more information, please contact:
Reinis Cimdins, [email protected], tel. +371 266 67206
