{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,16]],"date-time":"2026-05-16T18:01:42Z","timestamp":1778954502949,"version":"3.51.4"},"reference-count":55,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,12,26]],"date-time":"2021-12-26T00:00:00Z","timestamp":1640476800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100011219","name":"Minist\u00e8re des For\u00eats, de la Faune et des Parcs","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/100011219","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Direction g\u00e9n\u00e9ral du secteur nord-est, r\u00e9gion du Saguenay\u2013Lac-St-Jean,","award":["NA"],"award-info":[{"award-number":["NA"]}]},{"name":"For\u00eat d'Enseignement et de For\u00eat d'Enseignement et de","award":["NA"],"award-info":[{"award-number":["NA"]}]},{"name":"Parc National des Monts-Valin","award":["NA"],"award-info":[{"award-number":["NA"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Intercomparison of satellite-derived vegetation phenology is scarce in remote locations because of the limited coverage area and low temporal resolution of field observations. By their reliable near-ground observations and high-frequency data collection, PhenoCams can be a robust tool for intercomparison of land surface phenology derived from satellites. This study aims to investigate the transition dates of black spruce (Picea mariana (Mill.) B.S.P.) phenology by comparing fortnightly the MODIS normalized difference vegetation index (NDVI) and the enhanced vegetation index (EVI) extracted using the Google Earth Engine (GEE) platform with the daily PhenoCam-based green chromatic coordinate (GCC) index. Data were collected from 2016 to 2019 by PhenoCams installed in six mature stands along a latitudinal gradient of the boreal forests of Quebec, Canada. All time series were fitted by double-logistic functions, and the estimated parameters were compared between NDVI, EVI, and GCC. The onset of GCC occurred in the second week of May, whereas the ending of GCC occurred in the last week of September. We demonstrated that GCC was more correlated with EVI (R2 from 0.66 to 0.85) than NDVI (R2 from 0.52 to 0.68). In addition, the onset and ending of phenology were shown to differ by 3.5 and 5.4 days between EVI and GCC, respectively. Larger differences were detected between NDVI and GCC, 17.05 and 26.89 days for the onset and ending, respectively. EVI showed better estimations of the phenological dates than NDVI. This better performance is explained by the higher spectral sensitivity of EVI for multiple canopy leaf layers due to the presence of an additional blue band and an optimized soil factor value. Our study demonstrates that the phenological observations derived from PhenoCam are comparable with the EVI index. We conclude that EVI is more suitable than NDVI to assess phenology in evergreen species of the northern boreal region, where PhenoCam data are not available. The EVI index could be used as a reliable proxy of GCC for monitoring evergreen species phenology in areas with reduced access, or where repeated data collection from remote areas are logistically difficult due to the extreme weather.<\/jats:p>","DOI":"10.3390\/rs14010100","type":"journal-article","created":{"date-parts":[[2021,12,27]],"date-time":"2021-12-27T01:06:54Z","timestamp":1640567214000},"page":"100","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Comparing Time-Lapse PhenoCams with Satellite Observations across the Boreal Forest of Quebec, Canada"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6996-4583","authenticated-orcid":false,"given":"Siddhartha","family":"Khare","sequence":"first","affiliation":[{"name":"D\u00e9partement des Sciences Fondamentales, Universit\u00e9 du Qu\u00e9bec \u00e0 Chicoutimi, Chicoutimi, QC G7H 2B1, Canada"},{"name":"Department of Biology, McGill University, Montreal, QC H3A 1B1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Annie","family":"Deslauriers","sequence":"additional","affiliation":[{"name":"D\u00e9partement des Sciences Fondamentales, Universit\u00e9 du Qu\u00e9bec \u00e0 Chicoutimi, Chicoutimi, QC G7H 2B1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hubert","family":"Morin","sequence":"additional","affiliation":[{"name":"D\u00e9partement des Sciences Fondamentales, Universit\u00e9 du Qu\u00e9bec \u00e0 Chicoutimi, Chicoutimi, QC G7H 2B1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1054-889X","authenticated-orcid":false,"given":"Hooman","family":"Latifi","sequence":"additional","affiliation":[{"name":"Department of Photogrammetry and Remote Sensing, Faculty of Geodesy and Geomatics Engineering, K. N. Toosi University of Technology, Tehran 19967-15433, Iran"},{"name":"Department of Remote Sensing, University of W\u00fcrzburg, D-97070 W\u00fcrzburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sergio","family":"Rossi","sequence":"additional","affiliation":[{"name":"D\u00e9partement des Sciences Fondamentales, Universit\u00e9 du Qu\u00e9bec \u00e0 Chicoutimi, Chicoutimi, QC G7H 2B1, Canada"},{"name":"Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1174","DOI":"10.1111\/j.1365-2486.2006.01164.x","article-title":"Phenology of a northern hardwood forest canopy","volume":"12","author":"Richardson","year":"2006","journal-title":"Glob. Chang. 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