{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T14:56:05Z","timestamp":1776956165450,"version":"3.51.4"},"reference-count":59,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2017,11,28]],"date-time":"2017-11-28T00:00:00Z","timestamp":1511827200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Synthetic Aperture Radar Tomography (TomoSAR) allows the reconstruction of the 3D reflectivity of natural volume scatterers such as forests, thus providing an opportunity to infer structure information in 3D. In this paper, the potential of TomoSAR data at L-band to monitor temporal variations of forest structure is addressed using simulated and experimental datasets. First, 3D reflectivity profiles were extracted by means of TomoSAR reconstruction based on a Compressive Sensing (CS) approach. Next, two complementary indices for the description of horizontal and vertical forest structure were defined and estimated by means of the distribution of local maxima of the reconstructed reflectivity profiles. To assess the sensitivity and consistency of the proposed methodology, variations of these indices for different types of forest changes in simulated as well as in real scenarios were analyzed and assessed against different sources of reference data: airborne Lidar measurements, high resolution optical images, and forest inventory data. The forest structure maps obtained indicated the potential to distinguish between different forest stages and the identification of different types of forest structure changes induced by logging, natural disturbance, or forest management.<\/jats:p>","DOI":"10.3390\/rs9121229","type":"journal-article","created":{"date-parts":[[2017,11,28]],"date-time":"2017-11-28T11:23:50Z","timestamp":1511868230000},"page":"1229","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":62,"title":["Monitoring of Forest Structure Dynamics by Means of L-Band SAR Tomography"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6776-4553","authenticated-orcid":false,"given":"Victor","family":"Cazcarra-Bes","sequence":"first","affiliation":[{"name":"Microwaves and Radar Institute, German Aerospace Center (DLR), 82234 Oberpfaffenhofen, Germany"},{"name":"Institute of Environmental Engineering, ETH Zurich, 8093 Z\u00fcrich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria","family":"Tello-Alonso","sequence":"additional","affiliation":[{"name":"Microwaves and Radar Institute, German Aerospace Center (DLR), 82234 Oberpfaffenhofen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0482-0095","authenticated-orcid":false,"given":"Rico","family":"Fischer","sequence":"additional","affiliation":[{"name":"Department of Ecological Modelling, Helmholtz Centre for Environmental Research\u2014UFZ, Permoserstr. 15, 04318 Leipzig, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Heym","sequence":"additional","affiliation":[{"name":"Faculty of Forest Science and Resource Management, Technical University of Munich, Hans-Carl-v.-Carlowitz-Platz 2, 85354 Freising, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Konstantinos","family":"Papathanassiou","sequence":"additional","affiliation":[{"name":"Microwaves and Radar Institute, German Aerospace Center (DLR), 82234 Oberpfaffenhofen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,11,28]]},"reference":[{"key":"ref_1","first-page":"34","article-title":"Forest Structure: A Key to the Ecosystem","volume":"72","author":"Spies","year":"1998","journal-title":"Northwest Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1111\/j.0022-0477.2004.00874.x","article-title":"Understanding and managing the global carbon cycle","volume":"92","author":"Grace","year":"2004","journal-title":"J. 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