{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,10]],"date-time":"2026-01-10T23:20:47Z","timestamp":1768087247626,"version":"3.49.0"},"reference-count":65,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2015,1,29]],"date-time":"2015-01-29T00:00:00Z","timestamp":1422489600000},"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>The validation process for a moderate resolution leaf area index (LAI) product (i.e., MODIS) involves the creation of a high spatial resolution LAI reference map (Lai-RM), which when scaled to the moderate LAI resolution (i.e., &gt; 1 km) allows for comparison and analysis with this LAI product. This research addresses two major sources of uncertainty in the creation of the LAI-RM: (1) the uncertainty associated with the indirect in situ optical measurements of southeastern United States needle-leaf LAI and (2) the uncertainty in the process of classifying land cover (LC). Uncertainty within the loblolly pine (Pinus taeda) in situ data collection was highest for the assessment of the plant area index (PAI), Le (27.2%), and the woody-to-total ratio, \u03b1, (30.6%). The needle-to-shoot ratio, \u03bbE, and the element clumping index, \u03a9E, contributed 14.9% and 9.3%, respectively, to the uncertainty in the calculation of LAI. Combining LC differences (3.4%) with the uncertainty within the loblolly pine component resulted in doubling the LAI-RM variability (\u03c3 = 0.50 to \u03c3 = 0.97) at the 1 km2 validation site located in Appomattox, Virginia, USA.<\/jats:p>","DOI":"10.3390\/rs70201397","type":"journal-article","created":{"date-parts":[[2015,1,29]],"date-time":"2015-01-29T10:10:02Z","timestamp":1422526202000},"page":"1397-1421","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Uncertainty Analysis in the Creation of a Fine-Resolution Leaf Area Index (LAI) Reference Map for Validation of Moderate Resolution LAI Products"],"prefix":"10.3390","volume":"7","author":[{"given":"John","family":"Iiames","sequence":"first","affiliation":[{"name":"United States Environmental Protection Agency, 109 TW Alexander Dr. (MD E243-05), RTP,  NC 27711, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3891-2163","authenticated-orcid":false,"given":"Russell","family":"Congalton","sequence":"additional","affiliation":[{"name":"Department of Natural Resources and Environment, University of New Hampshire, 114 James Hall, Durham, NH 03824, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Timothy","family":"Lewis","sequence":"additional","affiliation":[{"name":"United States Army Corps of Engineers, Engineer Research and Development Center, 3909 Halls Ferry Rd, Vicksburg, MS 39180, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrew","family":"Pilant","sequence":"additional","affiliation":[{"name":"United States Environmental Protection Agency, 109 TW Alexander Dr. (MD E243-05), RTP,  NC 27711, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,1,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/0168-1923(95)02291-0","article-title":"Optically-based methods for measuring seasonal variation of leaf area index in boreal conifer stands","volume":"80","author":"Chen","year":"2006","journal-title":"Agr. 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