{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T05:45:03Z","timestamp":1790401503267,"version":"4.1.0"},"reference-count":44,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2010,12,29]],"date-time":"2010-12-29T00:00:00Z","timestamp":1293580800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this study, a semi-empirical model that was originally developed for stem volume estimation is used for aboveground biomass (AGB) estimation of a spruce dominated alpine forest. The reference AGB of the available sample plots is calculated from forest inventory data by means of biomass expansion factors. Furthermore, the semi-empirical model is extended by three different canopy transparency parameters derived from airborne LiDAR data. These parameters have not been considered for stem volume estimation until now and are introduced in order to investigate the behavior of the model concerning AGB estimation. The developed additional input parameters are based on the assumption that transparency of vegetation can be measured by determining the penetration of the laser beams through the canopy. These parameters are calculated for every single point within the 3D point cloud in order to consider the varying properties of the vegetation in an appropriate way. Exploratory Data Analysis (EDA) is performed to evaluate the influence of the additional LiDAR derived canopy transparency parameters for AGB estimation. The study is carried out in a 560 km2 alpine area in Austria, where reference forest inventory data and LiDAR data are available. The investigations show that the introduction of the canopy transparency parameters does not change the results significantly according to R2 (R2 = 0.70 to R2 = 0.71) in comparison to the results derived from, the semi-empirical model, which was originally developed for stem volume estimation.<\/jats:p>","DOI":"10.3390\/s110100278","type":"journal-article","created":{"date-parts":[[2010,12,29]],"date-time":"2010-12-29T10:48:11Z","timestamp":1293619691000},"page":"278-295","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Estimation of Aboveground Biomass in Alpine Forests: A Semi-Empirical Approach Considering Canopy Transparency Derived from Airborne LiDAR Data"],"prefix":"10.3390","volume":"11","author":[{"given":"Andreas","family":"Jochem","sequence":"first","affiliation":[{"name":"alpS-Centre for Climate Change Adaptation Technologies, Grabenweg 3, 6020 Innsbruck, Austria"},{"name":"Institute of Geography, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Markus","family":"Hollaus","sequence":"additional","affiliation":[{"name":"Vienna University of Technology, Institute of Photogrammetry and Remote Sensing, 1040 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6628-4681","authenticated-orcid":false,"given":"Martin","family":"Rutzinger","sequence":"additional","affiliation":[{"name":"Institute of Geography, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria"},{"name":"Faculty of Geo-Information Science and Earth Observation of the University of Twente (ITC), 7500 Enschede, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bernhard","family":"H\u00f6fle","sequence":"additional","affiliation":[{"name":"Department of Geography, University of Heidelberg, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2010,12,29]]},"reference":[{"key":"ref_1","unstructured":"Brown, S. (1997). FAO Forestry Paper, A Forest Resources Assessment Publication, Food and Agriculture Organization of the United Nations."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"945","DOI":"10.1111\/j.1365-2486.2005.00955.x","article-title":"Aboveground forest biomass and the global carbon balance","volume":"11","author":"Houghton","year":"2005","journal-title":"Glob. Change Biol"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2353","DOI":"10.1016\/j.rse.2010.05.011","article-title":"Estimating spruce and pine biomass with interferometric X-band SAR","volume":"114","author":"Solberg","year":"2010","journal-title":"Remote Sens. Environ"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1237","DOI":"10.1016\/j.foreco.2008.11.016","article-title":"Aboveground biomass assessment in Colombia: A remote sensing approach","volume":"257","author":"Anaya","year":"2009","journal-title":"Forest Ecol. Manage"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"402","DOI":"10.1016\/j.rse.2004.08.008","article-title":"Estimating aboveground biomass using Landsat 7 ETM + data a across managed landscape in northern Wisconsin, USA","volume":"93","author":"Zheng","year":"2004","journal-title":"Remote Sens. Environ"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Koch, B. (2010). Status and future of laser scanning, next term synthetic aperture radar and hyperspectral remote sensing data for forest biomass assessment. ISPRS J. Photogramm, in press.","DOI":"10.1016\/j.isprsjprs.2010.09.001"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1864","DOI":"10.3390\/rs2081864","article-title":"From TLS to VLS: Biomass estimation at individual tree level","volume":"2","author":"Lin","year":"2010","journal-title":"Remote Sens"},{"key":"ref_8","first-page":"47","article-title":"Biomass equations from data of old long-term experimental plots","volume":"123","author":"Ledermann","year":"2006","journal-title":"Austria. J. For. Sci"},{"key":"ref_9","first-page":"17","article-title":"Branch biomass functions for broadleaved tree species in Austria","volume":"123","author":"Gschwantner","year":"2006","journal-title":"Austria. J. For. Sci"},{"key":"ref_10","unstructured":"Weiss, P., Schieler, K., Schadauer, K., Radunsky, K., and Englisch, M. (2000). Die Kohlenstoffbilanz des \u00d6sterreichischen Waldes und Betrachtungen zum Kyoto-Protokoll, Umweltbundesamt. Technical Report 106;."},{"key":"ref_11","first-page":"45","article-title":"Allometric equations and expansion factors for tropical try forest trees of eastern Sinaloa, Mexico","volume":"10","year":"2009","journal-title":"Trop. Subtrop. Agroecosyst"},{"key":"ref_12","unstructured":"Hollaus, M. (2006). Large Scale Applications of Airborne Laser Scanning for a Complex Mountainous Environment, Ph.D. thesis,."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"415","DOI":"10.1016\/j.isprsjprs.2007.05.008","article-title":"Correction of laser scanning intensity data: Data and model-driven approaches","volume":"62","author":"Pfeifer","year":"2007","journal-title":"ISPRS J. Photogramm"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Kraus, K (2007). Photogrammetry: Geometry from Images and Laser Scans, Walter de Gruyter.","DOI":"10.1515\/9783110892871"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"558","DOI":"10.1080\/02827580410019490","article-title":"Estimation of above ground forest biomass from airborne discrete return laser scanner data using canopy-based quantile estimators","volume":"19","author":"Lim","year":"2004","journal-title":"Scand. J. Forest Res"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"342","DOI":"10.1016\/j.isprsjprs.2005.07.001","article-title":"Estimating forest biomass in small footprint LiDAR data: An individual tree-based approach that incorporates training data","volume":"59","author":"Bortolot","year":"2005","journal-title":"ISPRS J. Photogramm"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"182","DOI":"10.1016\/j.rse.2008.09.009","article-title":"Lidar remote sensing of forest biomass: A scale-invariant estimation approach using airborne lasers","volume":"113","author":"Zhao","year":"2009","journal-title":"Remote Sens. Environ"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1016\/0034-4257(88)90028-4","article-title":"Estimating forest biomass and volume using airborne laser data","volume":"24","author":"Nelson","year":"1988","journal-title":"Remote Sens. Environ"},{"key":"ref_19","first-page":"155","article-title":"Remote sensing of aboveground biomass in three biomes","volume":"XXXIV","author":"Lefsky","year":"2001","journal-title":"Int. Arch. Photogram. Rem. Sens. Spatial. Inform. Sci"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"658","DOI":"10.5589\/m03-025","article-title":"Lidar remote sensing of biophysical properties of tolerant northern hardwood forests","volume":"29","author":"Lim","year":"2003","journal-title":"Can. J. Rem. Sens"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"564","DOI":"10.5589\/m03-027","article-title":"Measuring individual tree crown diameter with lidar and assessing its influence on estimating forest volume and biomass","volume":"29","author":"Popescu","year":"2003","journal-title":"Can. J. Rem. Sens"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"500","DOI":"10.1080\/02827580410019508","article-title":"Measuring biomass and carbon in Delaware using an airborne profiling LIDAR","volume":"19","author":"Nelson","year":"2004","journal-title":"Scand. J. Forest Res"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"646","DOI":"10.1016\/j.biombioe.2007.06.022","article-title":"Estimating biomass of individual pine trees using airborne LiDAR","volume":"31","author":"Popescu","year":"2007","journal-title":"Biomass Bioenerg"},{"key":"ref_24","first-page":"145","article-title":"Estimation of above- and below-ground biomass in boreal forest ecosystems","volume":"XXXVI","year":"2004","journal-title":"Int. Arch. Photogram. Rem. Sens. Spatial. Inform. Sci"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1016\/j.isprsjprs.2006.10.006","article-title":"Classifying individual tree species under leaf-off and leaf-on conditions using airborne lidar","volume":"61","author":"Brandtberg","year":"2007","journal-title":"ISPRS J. Photogramm"},{"key":"ref_26","unstructured":"H\u00f6fle, B., Hollaus, M., Lehner, H., Pfeifer, N., and Wagner, W. (2008, January 17\u201319). Area-based parameterization of forest structure using full-waveform airborne laser scanning data. Edinburgh, Scotland."},{"key":"ref_27","unstructured":"Hollaus, M., M\u00fccke, W., H\u00f6fle, B., Dorigo, W., Pfeifer, N., Wagner, W., Bauerhansl, C., and Regner, B. (, January October). Tree species classification based on full-waveform airborne laser scanning data. College Station, TA, USA."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1575","DOI":"10.1016\/j.rse.2009.03.017","article-title":"Tree species differentiation using intensity data derived from leaf-on and leaf-off airborne laser scanner data","volume":"113","author":"Kim","year":"2009","journal-title":"Remote Sens. Environ"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"816","DOI":"10.1016\/j.rse.2009.11.021","article-title":"Estimating biomass carbon stocks for a Mediterranean forest in central Spain using LiDAR height and intensity data","volume":"114","author":"Chuvieco","year":"2010","journal-title":"Remote Sens. Environ"},{"key":"ref_30","unstructured":"Maas, H.G. (2010). Airborne and Terrestrial Laser Scanning, CRC Press Taylor and Francis Group."},{"key":"ref_31","unstructured":"Hyypp\u00e4, J., Hyypp\u00e4, H., Xiaowei, Y., Kaartinen, H., Kukko, A., and Holopainen, M (2009). Topographic Laser Ranging and Scanning: Principles and Processing, CRC Press Taylor & Francis Group."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1387","DOI":"10.1139\/X09-042","article-title":"Growing stock estimation for alpine forests in Austria: A robust LiDAR-based approach","volume":"39","author":"Hollaus","year":"2009","journal-title":"Can. J. Forest Res"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1080\/02827580310019257","article-title":"Practical large-scale forest stand inventory using a small foot print airborne scanning laser","volume":"19","year":"2004","journal-title":"Scand. J. Forest Res"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"5159","DOI":"10.1080\/01431160903022894","article-title":"Operational wide-area stem volume estimation based on airborne laser scanning and national forest inventory data","volume":"30","author":"Hollaus","year":"2009","journal-title":"Int. J. Remote Sens"},{"key":"ref_35","unstructured":"Available online: http:\/\/www.stand-montafon.at\/forstfonds (accessed on 1 October 2010)."},{"key":"ref_36","first-page":"4","article-title":"Die Winkelz\u00e4hlprobe","volume":"59","author":"Bitterlich","year":"1948","journal-title":"Allgemeine Forst- und Holzwirtschaftliche Zeitung"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1559","DOI":"10.3390\/s7081559","article-title":"Airborne laser scanning of forest stem volume in a mountainous environment","volume":"7","author":"Hollaus","year":"2007","journal-title":"Sensors"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1133","DOI":"10.1080\/01431160903380581","article-title":"An application-oriented automated approach for co-registration of forest inventory and airborne laser scanning data","volume":"31","author":"Dorigo","year":"2009","journal-title":"Int. J. Remote Sens"},{"key":"ref_39","unstructured":"K\u00f6rner, C., Schilcher, B., and Pel\u00e1ez-Riedl, S. (1993). Anthropogene Klima\u00e4nderungen: M\u00f6gliche Auswirkungen auf \u00d6sterreich m\u00f6gliche Massnahmen in \u00d6sterreich, Austrian Academy of Sciences Press (\u00d6AW)."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1016\/S0924-2716(98)00009-4","article-title":"Determination of terrain models in wooded areas with airborne laser scanner data","volume":"54","author":"Kraus","year":"1998","journal-title":"ISPRS J. Photogramm"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1387","DOI":"10.1080\/01431160701736349","article-title":"Assessment of the influence of flying altitude and scan angle on biophysical vegetation products derived from airborne laser scanning","volume":"29","author":"Morsdorf","year":"2008","journal-title":"Int. J. Remote Sens"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1016\/j.rse.2008.09.001","article-title":"Effects of different sensors, flying altitudes, and pulse repetition frequencies on forest canopy metrics and biophysical stand properties derived from small-footprint airborne laser data","volume":"113","author":"Naesset","year":"2009","journal-title":"Remote Sens. Environ"},{"key":"ref_43","unstructured":"H\u00f6fle, B., M\u00fccke, W., Dutter, M., Rutzinger, M., and Dorninger, P. (2009, January 7\u201310). Detection of building regions using airborne lidar\u2014A new combination of raster and point cloud based GIS methods. Salzburg, Austria."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"1546","DOI":"10.1016\/j.rse.2010.02.009","article-title":"Simulating the impact of discrete-return lidar system and survey characteristics over young conifer and broadleaf forests","volume":"114","author":"Disney","year":"2010","journal-title":"Remote Sens. Environ"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/11\/1\/278\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:04:14Z","timestamp":1760220254000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/11\/1\/278"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,12,29]]},"references-count":44,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2011,1]]}},"alternative-id":["s110100278"],"URL":"https:\/\/doi.org\/10.3390\/s110100278","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2010,12,29]]}}}