{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T08:10:32Z","timestamp":1767773432802,"version":"build-2065373602"},"reference-count":62,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2017,10,4]],"date-time":"2017-10-04T00:00:00Z","timestamp":1507075200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100011092","name":"Shell Exploration and Production Company","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011092","id-type":"DOI","asserted-by":"publisher"}]},{"name":"NASA","award":["NNX15AU05A"],"award-info":[{"award-number":["NNX15AU05A"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Ecosystem maps are foundational tools that support multi-disciplinary study design and applications including wildlife habitat assessment, monitoring and Earth-system modeling. Here, we present continuous-field cover maps for tundra plant functional types (PFTs) across ~125,000 km2 of Alaska\u2019s North Slope at 30-m resolution. To develop maps, we collected a field-based training dataset using a point-intercept sampling method at 225 plots spanning bioclimatic and geomorphic gradients. We stratified vegetation by nine PFTs (e.g., low deciduous shrub, dwarf evergreen shrub, sedge, lichen) and summarized measurements of the PFTs, open water, bare ground and litter using the cover metrics total cover (areal cover including the understory) and top cover (uppermost canopy or ground cover). We then developed 73 spectral predictors derived from Landsat satellite observations (surface reflectance composites for ~15-day periods from May\u2013August) and five gridded environmental predictors (e.g., summer temperature, climatological snow-free date) to model cover of PFTs using the random forest data-mining algorithm. Model performance tended to be best for canopy-forming PFTs, particularly deciduous shrubs. Our assessment of predictor importance indicated that models for low-statured PFTs were improved through the use of seasonal composites from early and late in the growing season, particularly when similar PFTs were aggregated together (e.g., total deciduous shrub, herbaceous). Continuous-field maps have many advantages over traditional thematic maps, and the methods described here are well-suited to support periodic map updates in tandem with future field and Landsat observations.<\/jats:p>","DOI":"10.3390\/rs9101024","type":"journal-article","created":{"date-parts":[[2017,10,4]],"date-time":"2017-10-04T13:53:55Z","timestamp":1507125235000},"page":"1024","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Regional Quantitative Cover Mapping of Tundra Plant Functional Types in Arctic Alaska"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2808-208X","authenticated-orcid":false,"given":"Matthew","family":"Macander","sequence":"first","affiliation":[{"name":"ABR, Inc.\u2014Environmental Research & Services, P.O. Box 80410, Fairbanks, AK 99708, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5134-0334","authenticated-orcid":false,"given":"Gerald","family":"Frost","sequence":"additional","affiliation":[{"name":"ABR, Inc.\u2014Environmental Research & Services, P.O. Box 80410, Fairbanks, AK 99708, USA"}]},{"given":"Peter","family":"Nelson","sequence":"additional","affiliation":[{"name":"University of Maine\u2014Fort Kent, 23 University Dr., Ft. Kent, ME 04743, USA"}]},{"given":"Christopher","family":"Swingley","sequence":"additional","affiliation":[{"name":"ABR, Inc.\u2014Environmental Research & Services, P.O. Box 80410, Fairbanks, AK 99708, USA"}]}],"member":"1968","published-online":{"date-parts":[[2017,10,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"222","DOI":"10.14430\/arctic1292","article-title":"Identification of tundra land cover near Teshekpuk Lake, Alaska using SPOT satellite data","volume":"47","author":"Markon","year":"1994","journal-title":"Arctic"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2921","DOI":"10.1080\/014311699211543","article-title":"Landsat MSS-derived land-cover map of northern Alaska: Extrapolation methods and a comparison with photo-interpreted and AVHRR-derived maps","volume":"20","author":"Muller","year":"1999","journal-title":"Int. J. Remote Sens."},{"key":"ref_3","unstructured":"Jorgenson, M.T., and Heiner, M. (2003). 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