{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,24]],"date-time":"2026-01-24T06:33:25Z","timestamp":1769236405121,"version":"3.49.0"},"reference-count":38,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,8]],"date-time":"2023-01-08T00:00:00Z","timestamp":1673136000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Doctoral Program in Sustainable Use of Renewable Natural Resources (AGFOREE) at the University of Helsinki","award":["Beetles LIFE (LIFE17\/NAT\/FI\/000181)"],"award-info":[{"award-number":["Beetles LIFE (LIFE17\/NAT\/FI\/000181)"]}]},{"name":"Doctoral Program in Sustainable Use of Renewable Natural Resources (AGFOREE) at the University of Helsinki","award":["312559"],"award-info":[{"award-number":["312559"]}]},{"name":"Doctoral Program in Sustainable Use of Renewable Natural Resources (AGFOREE) at the University of Helsinki","award":["337127"],"award-info":[{"award-number":["337127"]}]},{"name":"Doctoral Program in Sustainable Use of Renewable Natural Resources (AGFOREE) at the University of Helsinki","award":["334829"],"award-info":[{"award-number":["334829"]}]},{"name":"LIFE financial instrument of the European Union","award":["Beetles LIFE (LIFE17\/NAT\/FI\/000181)"],"award-info":[{"award-number":["Beetles LIFE (LIFE17\/NAT\/FI\/000181)"]}]},{"name":"LIFE financial instrument of the European Union","award":["312559"],"award-info":[{"award-number":["312559"]}]},{"name":"LIFE financial instrument of the European Union","award":["337127"],"award-info":[{"award-number":["337127"]}]},{"name":"LIFE financial instrument of the European Union","award":["334829"],"award-info":[{"award-number":["334829"]}]},{"name":"Academy of Finland\u2019s Strategic Research Council","award":["Beetles LIFE (LIFE17\/NAT\/FI\/000181)"],"award-info":[{"award-number":["Beetles LIFE (LIFE17\/NAT\/FI\/000181)"]}]},{"name":"Academy of Finland\u2019s Strategic Research Council","award":["312559"],"award-info":[{"award-number":["312559"]}]},{"name":"Academy of Finland\u2019s Strategic Research Council","award":["337127"],"award-info":[{"award-number":["337127"]}]},{"name":"Academy of Finland\u2019s Strategic Research Council","award":["334829"],"award-info":[{"award-number":["334829"]}]},{"name":"Academy of Finland\u2019s Flagship Program","award":["Beetles LIFE (LIFE17\/NAT\/FI\/000181)"],"award-info":[{"award-number":["Beetles LIFE (LIFE17\/NAT\/FI\/000181)"]}]},{"name":"Academy of Finland\u2019s Flagship Program","award":["312559"],"award-info":[{"award-number":["312559"]}]},{"name":"Academy of Finland\u2019s Flagship Program","award":["337127"],"award-info":[{"award-number":["337127"]}]},{"name":"Academy of Finland\u2019s Flagship Program","award":["334829"],"award-info":[{"award-number":["334829"]}]},{"name":"Academy of Finland\u2019s Research Council for Natural Sciences and Engineering","award":["Beetles LIFE (LIFE17\/NAT\/FI\/000181)"],"award-info":[{"award-number":["Beetles LIFE (LIFE17\/NAT\/FI\/000181)"]}]},{"name":"Academy of Finland\u2019s Research Council for Natural Sciences and Engineering","award":["312559"],"award-info":[{"award-number":["312559"]}]},{"name":"Academy of Finland\u2019s Research Council for Natural Sciences and Engineering","award":["337127"],"award-info":[{"award-number":["337127"]}]},{"name":"Academy of Finland\u2019s Research Council for Natural Sciences and Engineering","award":["334829"],"award-info":[{"award-number":["334829"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Fallen tree mapping provides valuable information regarding the ecological value of boreal forests. Airborne laser scanning (ALS) enables mapping fallen trees on a large scale. We compared the performance of line-detection-based individual fallen tree detection when using moderate point density ALS data (15 points\/m2) and high-point-density unmanned aerial vehicle-based laser scanning (ULS) data (285 points\/m2). Furthermore, we inspected the dataset and detection methodology-related factors impacting performance in each case. The results of this study showed that increasing the point density of the laser scanning dataset enables the detection of a larger proportion of fallen trees. However, based on our experiment, a line-detection-based fallen tree detection approach is sensitive to noise, thus generating a large number of false detections, especially with high-point-density data. Different types of filters, such as a simple height-based filter and machine-learning-based filters, can be used for reducing noise. However, using such filters is always a compromise, as in addition to reducing noise and thus false detections, they also reduce the number of true detections. Hence, a less noise-sensitive fallen tree detection method utilizing the finer details visible in high-density point clouds could be more suitable for high-point-density laser scanning data.<\/jats:p>","DOI":"10.3390\/rs15020382","type":"journal-article","created":{"date-parts":[[2023,1,9]],"date-time":"2023-01-09T04:47:08Z","timestamp":1673239628000},"page":"382","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Evaluating Factors Impacting Fallen Tree Detection from Airborne Laser Scanning Point Clouds"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2606-6131","authenticated-orcid":false,"given":"Einari","family":"Heinaro","sequence":"first","affiliation":[{"name":"Department of Forest Sciences, University of Helsinki, 00014 Helsinki, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5509-6922","authenticated-orcid":false,"given":"Topi","family":"Tanhuanp\u00e4\u00e4","sequence":"additional","affiliation":[{"name":"Department of Forest Sciences, University of Helsinki, 00014 Helsinki, Finland"},{"name":"Department of Geographical and Historical Studies, University of Eastern Finland, 80101 Joensuu, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6552-9122","authenticated-orcid":false,"given":"Mikko","family":"Vastaranta","sequence":"additional","affiliation":[{"name":"School of Forest Sciences, University of Eastern Finland, 80101 Joensuu, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2648-523X","authenticated-orcid":false,"given":"Tuomas","family":"Yrttimaa","sequence":"additional","affiliation":[{"name":"Department of Forest Sciences, University of Helsinki, 00014 Helsinki, Finland"},{"name":"School of Forest Sciences, University of Eastern Finland, 80101 Joensuu, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3841-6533","authenticated-orcid":false,"given":"Antero","family":"Kukko","sequence":"additional","affiliation":[{"name":"Department of Remote Sensing and Photogrammetry, Finnish Geospatial Research Institute FGI, The National Land Survey of Finland, 02150 Espoo, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5486-4582","authenticated-orcid":false,"given":"Teemu","family":"Hakala","sequence":"additional","affiliation":[{"name":"Department of Remote Sensing and Photogrammetry, Finnish Geospatial Research Institute FGI, The National Land Survey of Finland, 02150 Espoo, Finland"}]},{"given":"Teppo","family":"Mattsson","sequence":"additional","affiliation":[{"name":"Department of Forest Sciences, University of Helsinki, 00014 Helsinki, Finland"}]},{"given":"Markus","family":"Holopainen","sequence":"additional","affiliation":[{"name":"Department of Forest Sciences, University of Helsinki, 00014 Helsinki, Finland"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Stokland, J.N., Jonsson, B.G., and Siitonen, J. 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