{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T23:44:35Z","timestamp":1768347875195,"version":"3.49.0"},"reference-count":20,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2009,12,22]],"date-time":"2009-12-22T00:00:00Z","timestamp":1261440000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>A new simple airborne method based on wide optics camera is developed for leaf area index (LAI) estimation in coniferous forests. The measurements are carried out in winter, when the forest floor is completely snow covered and thus acts as a light background for the hemispherical analysis of the images. The photos are taken automatically and stored on a laptop during the flights. The R2 value of the linear regression of the airborne and ground based LAI measurements was 0.89.<\/jats:p>","DOI":"10.3390\/rs1041380","type":"journal-article","created":{"date-parts":[[2009,12,22]],"date-time":"2009-12-22T10:56:36Z","timestamp":1261479396000},"page":"1380-1394","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Leaf Area Index (LAI) Estimation of Boreal Forest Using Wide Optics Airborne Winter Photos"],"prefix":"10.3390","volume":"1","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8945-9122","authenticated-orcid":false,"given":"Terhikki","family":"Manninen","sequence":"first","affiliation":[{"name":"Finnish Meteorological Institute, P.O. Box 503, FI-00101, Helsinki, Finland"}]},{"given":"Lauri","family":"Korhonen","sequence":"additional","affiliation":[{"name":"Faculty of Forest Sciences, P.O. Box 111, University of Joensuu, FI-80101, Joensuu, Finland"}]},{"given":"Pekka","family":"Voipio","sequence":"additional","affiliation":[{"name":"Suonenjoki Research Unit, Finnish Forest Research Institute (Metla), Juntintie 154, FI-77600, Finland"}]},{"given":"Panu","family":"Lahtinen","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, P.O. Box 503, FI-00101, Helsinki, Finland"}]},{"given":"Pauline","family":"Stenberg","sequence":"additional","affiliation":[{"name":"Department of Forest Resource Management, P.O.Box 27, University of Helsinki, FI-00014, Finland"}]}],"member":"1968","published-online":{"date-parts":[[2009,12,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"716","DOI":"10.1038\/359716a0","article-title":"Effects of boreal forest vegetation on global climate","volume":"359","author":"Bonan","year":"1992","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1130","DOI":"10.1126\/science.1132075","article-title":"The Impact of Boreal Forest Fire on Climate Warming","volume":"314","author":"Randerson","year":"2006","journal-title":"Science"},{"key":"ref_3","unstructured":"Parry, M.L., Canziani, O.F., Palutikof, J.P., van der Linden, P.J., and Hanson, C.E. (2007). IPCC: Climate Change 2007: Impacts, Adaptation and Vulnerability. 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