{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T22:37:16Z","timestamp":1788388636685,"version":"build-2803163510"},"reference-count":55,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,8]],"date-time":"2018-10-08T00:00:00Z","timestamp":1538956800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002749","name":"Federaal Wetenschapsbeleid","doi-asserted-by":"publisher","award":["SR\/00\/134"],"award-info":[{"award-number":["SR\/00\/134"]}],"id":[{"id":"10.13039\/501100002749","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this analysis, a method for construction of forest canopy three-dimensional (3D) models from terrestrial LiDAR was used for assessing the influence of structural changes on reflectance for an even-aged forest in Belgium. The necessary data were extracted by the developed method, as well as it was registered the adjacent point-clouds, and the canopy elements were classified. Based on a voxelized approach, leaf area index (LAI) and the vertical distribution of leaf area density (LAD) of the forest canopy were derived. Canopy\u2013radiation interactions were simulated in a ray tracing environment, giving suitable illumination properties and optical attributes of the different canopy elements. Canopy structure was modified in terms of LAI and LAD for hyperspectral measurements. It was found that the effect of a 10% increase in LAI on NIR reflectance can be equal to change caused by translating 50% of leaf area from top to lower layers. As presented, changes in structure did affect vegetation indices associated with LAI and chlorophyll content. Overall, the work demonstrated the ability of terrestrial LiDAR for detailed canopy assessments and revealed the high complexity of the relationship between vertical LAD and reflectance.<\/jats:p>","DOI":"10.3390\/s18103357","type":"journal-article","created":{"date-parts":[[2018,10,8]],"date-time":"2018-10-08T10:44:53Z","timestamp":1538995493000},"page":"3357","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["A Simulation Study Using Terrestrial LiDAR Point Cloud Data to Quantify Spectral Variability of a Broad-Leaved Forest Canopy"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4000-3711","authenticated-orcid":false,"given":"Renato","family":"Cifuentes","sequence":"first","affiliation":[{"name":"H\u00e9mera Centro de Observaci\u00f3n de la Tierra, Facultad de Ciencias, Universidad Mayor, Santiago 8340589, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dimitry","family":"Van der Zande","sequence":"additional","affiliation":[{"name":"Directorate Natural Environment, Royal Belgian Institute of Natural Sciences, 1000 Brussels, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Salas-Eljatib","sequence":"additional","affiliation":[{"name":"Centro de Modelaci\u00f3n y Monitoreo de Ecosistemas, Facultad de Ciencias, Universidad Mayor, Santiago 8340589, Chile"},{"name":"Laboratorio de Biometr\u00eda, Universidad de La Frontera, Temuco 4811230, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jamshid","family":"Farifteh","sequence":"additional","affiliation":[{"name":"Department of Biosystem, Katholieke Universiteit Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pol","family":"Coppin","sequence":"additional","affiliation":[{"name":"Department of Biosystem, Katholieke Universiteit Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"359","DOI":"10.1177\/030913339902300303","article-title":"Hyperspectral remote sensing for estimating biophysical parameters of forest ecosystems","volume":"23","author":"Treitz","year":"1999","journal-title":"Prog. 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