{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T23:16:39Z","timestamp":1769555799822,"version":"3.49.0"},"reference-count":48,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,11]],"date-time":"2018-10-11T00:00:00Z","timestamp":1539216000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000104","name":"National Aeronautics and Space Administration","doi-asserted-by":"publisher","award":["NNX11AO47G"],"award-info":[{"award-number":["NNX11AO47G"]}],"id":[{"id":"10.13039\/100000104","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Digital cameras can provide a consistent view of vegetation phenology at fine spatial and temporal scales that are impractical to collect manually and are currently unobtainable by satellite and most aerial based sensors. This study links greenness indices derived from digital images in a network of rangeland and forested sites in Montana and Idaho to 16-day normalized difference vegetation index (NDVI) from NASA\u2019s Moderate Resolution Imaging Spectroradiometer (MODIS). Multiple digital cameras were placed along a transect at each site to increase the observational footprint and correlation with the coarser MODIS NDVI. Digital camera phenology indices were averaged across cameras on a site to derive phenological curves. The phenology curves, as well as green-up dates, and maximum growth dates, were highly correlated to the satellite derived MODIS composite NDVI 16-day data at homogeneous rangeland vegetation sites. Forested and mixed canopy sites had lower correlation and variable significance. This result suggests the use of MODIS NDVI in forested sites to evaluate understory phenology may not be suitable. This study demonstrates that data from digital camera networks with multiple cameras per site can be used to reliably estimate measures of vegetation phenology in rangelands and that those data are highly correlated to MODIS 16-day NDVI.<\/jats:p>","DOI":"10.3390\/rs10101612","type":"journal-article","created":{"date-parts":[[2018,10,12]],"date-time":"2018-10-12T02:58:04Z","timestamp":1539313084000},"page":"1612","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Linking Phenological Indices from Digital Cameras in Idaho and Montana to MODIS NDVI"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0129-2204","authenticated-orcid":false,"given":"Joseph","family":"St. Peter","sequence":"first","affiliation":[{"name":"W.A. Franke College of Forestry and Conservation, University of Montana, Missoula, MT 59812, USA"}]},{"given":"John","family":"Hogland","sequence":"additional","affiliation":[{"name":"Rocky Mountain Research Station, U.S. Forest Service, Missoula, MT 59801, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5382-1361","authenticated-orcid":false,"given":"Mark","family":"Hebblewhite","sequence":"additional","affiliation":[{"name":"Wildlife Biology Program, W.A. Franke College of Forestry and Conservation, University of Montana, Missoula, MT 59812, USA"}]},{"given":"Mark A.","family":"Hurley","sequence":"additional","affiliation":[{"name":"Idaho Department of Fish and Game, 600 S. Walnut Street, Boise, ID 83712, USA"}]},{"given":"Nicole","family":"Hupp","sequence":"additional","affiliation":[{"name":"Mojave Desert Network Inventory &amp; Monitoring Program, National Park Service, 101 Nevada Way, Boulder City, NV 89005, USA"}]},{"given":"Kelly","family":"Proffitt","sequence":"additional","affiliation":[{"name":"Montana Department of Fish, Wildlife and Parks, 1400 South 19th Street, Bozeman, MT 59718, USA"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,11]]},"reference":[{"key":"ref_1","unstructured":"Schwartz, M. (2013). Remote Sensing of Land Surface: A Prospectus. Phenology: An Integrated Environmental Science, Springer. [2nd ed.]. Chapter 21."},{"key":"ref_2","unstructured":"Parry, M.L., Canziani, O.F., Palutikof, J.P., van der Linden, P.J., and Hanson, C.E. (2007). Assessment of observed changes and responses in natural and managed systems. Climate Change 2007: Impacts, Adaptation and Vulnerability, Cambridge University Press. 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