{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T15:31:10Z","timestamp":1780327870853,"version":"3.54.1"},"reference-count":49,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2019,4,9]],"date-time":"2019-04-09T00:00:00Z","timestamp":1554768000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Dr. Erich-Ritter-Foundation","award":["T0021\/29427\/2017"],"award-info":[{"award-number":["T0021\/29427\/2017"]}]},{"name":"German Research Foundation","award":["SE2383\/4-1"],"award-info":[{"award-number":["SE2383\/4-1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Understory vegetation influences several ecosystem services and functions of European beech (Fagus sylvatica L.) forests. Despite this knowledge on the importance of understory vegetation, it is still difficult to measure its three-dimensional characteristics in a quantitative manner. With the recent advancements in terrestrial laser scanning (TLS), we now have the means to analyze detailed spatial patterns of forests. Here, we present a new measure to quantify understory complexity. We tested the approach for different management types, ranging from traditionally and alternatively managed forests and national parks in Germany to primary forests of Eastern Europe and the Ukraine, as well as on an inventory site with more detailed understory reference data. The understory complexity index (UCI) was derived from point clouds from single scans and tested for its relationship with forest management and conventional inventory data. Our results show that advanced tree regeneration is a strong driver of the UCI. Furthermore, the newly developed index successfully measured understory complexity of differently managed beech stands and was able to distinguish scanning positions located on and away from skid-trails in managed stands. The approach enables a deeper understanding of the complexity of understory structures of forests and their drivers and dependents.<\/jats:p>","DOI":"10.3390\/s19071684","type":"journal-article","created":{"date-parts":[[2019,4,9]],"date-time":"2019-04-09T05:58:07Z","timestamp":1554789487000},"page":"1684","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Assessing Understory Complexity in Beech-dominated Forests (Fagus sylvatica L.) in Central Europe\u2014From Managed to Primary Forests"],"prefix":"10.3390","volume":"19","author":[{"given":"Katharina","family":"Willim","sequence":"first","affiliation":[{"name":"Faculty of Forest Sciences, Silviculture and Forest Ecology of the temperate Zones, University of G\u00f6ttingen, B\u00fcsgenweg 1, 37077 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Melissa","family":"Stiers","sequence":"additional","affiliation":[{"name":"Faculty of Forest Sciences, Silviculture and Forest Ecology of the temperate Zones, University of G\u00f6ttingen, B\u00fcsgenweg 1, 37077 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter","family":"Annigh\u00f6fer","sequence":"additional","affiliation":[{"name":"Faculty of Forest Sciences, Silviculture and Forest Ecology of the temperate Zones, University of G\u00f6ttingen, B\u00fcsgenweg 1, 37077 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4235-0135","authenticated-orcid":false,"given":"Christian","family":"Ammer","sequence":"additional","affiliation":[{"name":"Faculty of Forest Sciences, Silviculture and Forest Ecology of the temperate Zones, University of G\u00f6ttingen, B\u00fcsgenweg 1, 37077 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin","family":"Ehbrecht","sequence":"additional","affiliation":[{"name":"Faculty of Forest Sciences, Silviculture and Forest Ecology of the temperate Zones, University of G\u00f6ttingen, B\u00fcsgenweg 1, 37077 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9256-2531","authenticated-orcid":false,"given":"Myroslav","family":"Kabal","sequence":"additional","affiliation":[{"name":"Carpathian Biosphere Reserve, Laboratory of Forest Sciences, Krasne Pleso 77, 90600 Rakhiv, Ukraine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonas","family":"Stillhard","sequence":"additional","affiliation":[{"name":"Forest Resources and Management, WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Z\u00fcrcherstrasse 11, 8903 Birmensdorf, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4131-9424","authenticated-orcid":false,"given":"Dominik","family":"Seidel","sequence":"additional","affiliation":[{"name":"Faculty of Forest Sciences, Silviculture and Forest Ecology of the temperate Zones, University of G\u00f6ttingen, B\u00fcsgenweg 1, 37077 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,4,9]]},"reference":[{"key":"ref_1","unstructured":"Helms, J.A. 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