{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T21:33:24Z","timestamp":1792532004747,"version":"4.5.0"},"reference-count":68,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2018,9,11]],"date-time":"2018-09-11T00:00:00Z","timestamp":1536624000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005357","name":"Agent\u00fara na Podporu V\u00fdskumu a V\u00fdvoja","doi-asserted-by":"publisher","award":["APVV-16-0326"],"award-info":[{"award-number":["APVV-16-0326"]}],"id":[{"id":"10.13039\/501100005357","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006109","name":"Vedeck\u00e1 Grantov\u00e1 Agent\u00fara M\u0160VVa\u0160 SR a SAV","doi-asserted-by":"publisher","award":["1\/0387\/18"],"award-info":[{"award-number":["1\/0387\/18"]}],"id":[{"id":"10.13039\/501100006109","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Internal Grant Agency of the Faculty of Forestry and Wood Sciences, project IGA","award":["A07\/18"],"award-info":[{"award-number":["A07\/18"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Forests"],"abstract":"<jats:p>The study is focused on the surface changes of five hardwoods (oak, black locust, poplar, alder and maple) that were exposed to natural weathering for 24 months in the climatic conditions of Central Europe. Colour, roughness, visual and chemical changes of exposed surface structures were examined. The lowest total colour changes (\u0394E*) were found for oak (23.77), the highest being recorded for maple (34.19). Roughness differences after 24-month exposure (\u0394Ra) showed minimal changes in poplar wood (9.41); the highest changes in roughness were found on the surface of alder (22.18). The presence of mould and blue stains was found on the surface of maple, alder and poplar. Chemical changes were characterized by lignin and hemicelluloses degradation. Decreases of both methoxy and carbonyl groups, cleavage of bonds in lignin and hemicelluloses, oxidation reaction and formation of new chromophores were observed. In the initial phases of the degradation process, the discoloration was related to chemical changes; in the longer period, the greying due to settling of dust particles and action of mould influenced the wood colour. The data were confirmed by confocal laser scanning microscopy. The obtained results revealed degradation processes of tested hardwood surfaces exposed to external environmental factors.<\/jats:p>","DOI":"10.3390\/f9090557","type":"journal-article","created":{"date-parts":[[2018,9,11]],"date-time":"2018-09-11T11:40:02Z","timestamp":1536666002000},"page":"557","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Surface Changes of Selected Hardwoods Due to Weather Conditions"],"prefix":"10.3390","volume":"9","author":[{"given":"Ivan","family":"Kubovsk\u00fd","sequence":"first","affiliation":[{"name":"Faculty of Wood Sciences and Technology, Technical University in Zvolen, T.G. Masaryka 24, 960 53 Zvolen, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eli\u0161ka","family":"Oberhofnerov\u00e1","sequence":"additional","affiliation":[{"name":"Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Kam\u00fdck\u00e1 129, 16521 Praha 6-Suchdol, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8989-0833","authenticated-orcid":false,"given":"Franti\u0161ek","family":"Ka\u010d\u00edk","sequence":"additional","affiliation":[{"name":"Faculty of Wood Sciences and Technology, Technical University in Zvolen, T.G. Masaryka 24, 960 53 Zvolen, Slovakia"},{"name":"Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Kam\u00fdck\u00e1 129, 16521 Praha 6-Suchdol, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milo\u0161","family":"P\u00e1nek","sequence":"additional","affiliation":[{"name":"Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Kam\u00fdck\u00e1 129, 16521 Praha 6-Suchdol, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,9,11]]},"reference":[{"key":"ref_1","unstructured":"Lesar, B., Humar, M., Kr\u017ei\u0161nik, D., Thaler, N., and \u017dlahti\u010d, M. (2016, January 22\u201325). Performance of fa\u00e7ade elements made of five different thermally modified wood species on model house in Ljubljana. Proceedings of the World Conference on Timber Engineering, Vienna, Austria. 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