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Borges and Susete Marques were financially supported by Portuguese national funds through the Foundation for Science and Technology I.P.","award":["2022.13033.BD"],"award-info":[{"award-number":["2022.13033.BD"]}]},{"name":"Jos\u00e9 G. Borges and Susete Marques were financially supported by Portuguese national funds through the Foundation for Science and Technology I.P.","award":["101007950\u2014H2020-MSCA-RISE-2020"],"award-info":[{"award-number":["101007950\u2014H2020-MSCA-RISE-2020"]}]},{"name":"Jos\u00e9 G. Borges and Susete Marques were financially supported by Portuguese national funds through the Foundation for Science and Technology I.P.","award":["UIDB\/00239\/2020"],"award-info":[{"award-number":["UIDB\/00239\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sustainability"],"abstract":"<jats:p>Forest managers need inventory data and information to address sustainability concerns over extended temporal horizons. In situ information is usually derived from field data and computed using appropriate equations. Nonetheless, fieldwork is time-consuming and costly. Thus, new technologies like Light Detection and Ranging (LiDAR) have emerged as an alternative method for forest assessment. In this study, we evaluated the accuracy of geostatistical methods in predicting the Site Index (SI) using LiDAR metrics as auxiliary variables. Since primary variables, which were obtained from forestry inventory data, were used to calculate the SI, secondary variables obtained from LiDAR surveying were considered and multivariate kriging techniques were tested. The ordinary cokriging (CK) method outperformed the simple cokriging (SK) and Inverse Distance Weighted (IDW) methods, which was interpolated using only the primary variable. Aside from having fewer SI sample points, CK was proven to be a trustworthy interpolation method, minimizing interpolation errors due to the highly correlated auxiliary variables, highlighting the significance of the data\u2019s spatial structure and autocorrelation in predicting forest stand attributes, such as the SI. CK increased the SI prediction accuracy by 36.6% for eucalyptus, 62% for maritime pine, 72% for pedunculate oak, and 43% for cork oak compared to IDW, outperforming this interpolation approach. Although cokriging modeling is challenging, it is an appealing alternative to non-spatial statistics for improving forest management sustainability since the results are unbiased and trustworthy, making the effort worthwhile when dense secondary variables are available.<\/jats:p>","DOI":"10.3390\/su16156423","type":"journal-article","created":{"date-parts":[[2024,7,26]],"date-time":"2024-07-26T14:39:08Z","timestamp":1722004748000},"page":"6423","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Enhancing Forest Site Classification in Northwest Portugal: A Geostatistical Approach Employing Cokriging"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7721-008X","authenticated-orcid":false,"given":"Barbara","family":"Pavani-Biju","sequence":"first","affiliation":[{"name":"Department of Geosciences, Environment and Land Planning, University of Porto, Rua Campo Alegre, 687, 4169-007 Porto, Portugal"},{"name":"Earth Sciences Institute (ICT), Pole of the FCUP, University of Porto, 4169-007 Porto, Portugal"},{"name":"Forest Research Centre, School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0608-5784","authenticated-orcid":false,"given":"Jos\u00e9 G.","family":"Borges","sequence":"additional","affiliation":[{"name":"Forest Research Centre, Associate Laboratory TERRA, School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7922-5680","authenticated-orcid":false,"given":"Susete","family":"Marques","sequence":"additional","affiliation":[{"name":"Forest Research Centre, Associate Laboratory TERRA, School of Agriculture, University of Lisbon, Tapada da Ajuda, 1349-017 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8043-6431","authenticated-orcid":false,"given":"Ana C.","family":"Teodoro","sequence":"additional","affiliation":[{"name":"Department of Geosciences, Environment and Land Planning, University of Porto, Rua Campo Alegre, 687, 4169-007 Porto, Portugal"},{"name":"Earth Sciences Institute (ICT), Pole of the FCUP, University of Porto, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1016\/S0065-2113(08)70011-7","article-title":"Forest Site Quality Evaluation in The United States","volume":"27","author":"Carmean","year":"1975","journal-title":"Adv. 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