{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T02:22:45Z","timestamp":1773886965184,"version":"3.50.1"},"reference-count":53,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2016,8,10]],"date-time":"2016-08-10T00:00:00Z","timestamp":1470787200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000266","name":"Engineering and Physical Sciences Research Council","doi-asserted-by":"publisher","award":["08002930"],"award-info":[{"award-number":["08002930"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100011246","name":"Environment Agency","doi-asserted-by":"publisher","award":["08002930"],"award-info":[{"award-number":["08002930"]}],"id":[{"id":"10.13039\/100011246","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Potdoctoral Scholarship Programa Operative 2007-2013 de Castilla-La Mancha","award":["-"],"award-info":[{"award-number":["-"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Existing regulatory frameworks aiming to improve the quality of rivers place hydromorphology as a key factor in the assessment of hydrology, morphology and river continuity. The majority of available methods for hydromorphological characterisation rely on the identification of homogeneous areas (i.e., features) of flow, vegetation and substrate. For that purpose, aerial imagery is used to identify existing features through either visual observation or automated classification techniques. There is evidence to believe that the success in feature identification relies on the resolution of the imagery used. However, little effort has yet been made to quantify the uncertainty in feature identification associated with the resolution of the aerial imagery. This paper contributes to address this gap in knowledge by contrasting results in automated hydromorphological feature identification from unmanned aerial vehicles (UAV) aerial imagery captured at three resolutions (2.5 cm, 5 cm and 10 cm) along a 1.4 km river reach. The results show that resolution plays a key role in the accuracy and variety of features identified, with larger identification errors observed for riffles and side bars. This in turn has an impact on the ecological characterisation of the river reach. The research shows that UAV technology could be essential for unbiased hydromorphological assessment.<\/jats:p>","DOI":"10.3390\/rs8080650","type":"journal-article","created":{"date-parts":[[2016,8,10]],"date-time":"2016-08-10T10:14:10Z","timestamp":1470824050000},"page":"650","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Quantifying the Effect of Aerial Imagery Resolution in Automated Hydromorphological River Characterisation"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4169-3099","authenticated-orcid":false,"given":"Monica","family":"Rivas Casado","sequence":"first","affiliation":[{"name":"School of Energy, Environment and Agrifood, Cranfield University, Cranfield MK430AL, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6496-4421","authenticated-orcid":false,"given":"Rocio","family":"Ballesteros Gonzalez","sequence":"additional","affiliation":[{"name":"Regional Centre of Water Research (UCLM), Ctra. de las Pe\u00f1as km 3.2, Albacete 02071, Spain"}]},{"given":"Ros","family":"Wright","sequence":"additional","affiliation":[{"name":"National Fisheries Services, Environment Agency, Threshelfords Business Park, Inworth Rd., Feering, Essex CO6 1UD, UK"}]},{"given":"Pat","family":"Bellamy","sequence":"additional","affiliation":[{"name":"School of Energy, Environment and Agrifood, Cranfield University, Cranfield MK430AL, UK"}]}],"member":"1968","published-online":{"date-parts":[[2016,8,10]]},"reference":[{"key":"ref_1","unstructured":"Australian and New Zealand Environment Conservation Council (2000). 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