{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:46:21Z","timestamp":1760143581647,"version":"build-2065373602"},"reference-count":54,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,2,20]],"date-time":"2024-02-20T00:00:00Z","timestamp":1708387200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Paul G Allen Philanthropies","award":["GPA-2018"],"award-info":[{"award-number":["GPA-2018"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Corals are habitat-forming organisms on tropical and sub-tropical reefs, often displaying diverse phenotypic behaviors that challenge field-based monitoring and assessment efforts. Symbiont chlorophyll (Chl) is a long-recognized indicator of intra- and inter-specific variation in coral\u2019s response to environmental variability and stress, but the quantitative Chl assessment of corals at the reef scale continues to prove challenging. We integrated field, airborne, and laboratory techniques to test and apply the use of reflectance spectroscopy for in situ and reef-scale estimation of Chl a and Chl c2 concentrations in a shallow reef environment of K\u0101ne\u2018ohe Bay, O\u2018ahu. High-fidelity spectral signatures (420\u2013660 nm) derived from field and airborne spectroscopy quantified Chl a and Chl c2 concentrations with demonstrable precision and accuracy. Airborne imaging spectroscopy revealed a 10-fold range of Chl concentrations across the reef ecosystem. We discovered a differential pattern of Chl a and Chl c2 use in symbiont algae in coexisting corals indicative of a physiological response to decreasing light levels with increasing water depth. The depth-dependent ratio of Chl c2:a indicated the presence of two distinct light-driven habitats spanning just 5 m of water depth range. Our findings provide a pathway for further study of coral pigment responses to environmental conditions using field and high-resolution airborne imaging spectroscopy.<\/jats:p>","DOI":"10.3390\/rs16050732","type":"journal-article","created":{"date-parts":[[2024,2,20]],"date-time":"2024-02-20T07:50:26Z","timestamp":1708415426000},"page":"732","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Variability in Symbiont Chlorophyll of Hawaiian Corals from Field and Airborne Spectroscopy"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7893-6421","authenticated-orcid":false,"given":"Gregory P.","family":"Asner","sequence":"first","affiliation":[{"name":"Center for Global Discovery and Conservation Science, Arizona State University, Hilo, HI 96720, USA"},{"name":"School of Ocean Futures, Arizona State University, Hilo, HI 96720, USA"}]},{"given":"Crawford","family":"Drury","sequence":"additional","affiliation":[{"name":"Hawai\u2018i Institute of Marine Biology, University of Hawai\u2018i, Kaneohe, HI 96744, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0428-2909","authenticated-orcid":false,"given":"Nicholas R.","family":"Vaughn","sequence":"additional","affiliation":[{"name":"Center for Global Discovery and Conservation Science, Arizona State University, Hilo, HI 96720, USA"}]},{"given":"Joshua R.","family":"Hancock","sequence":"additional","affiliation":[{"name":"Hawai\u2018i Institute of Marine Biology, University of Hawai\u2018i, Kaneohe, HI 96744, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3509-8530","authenticated-orcid":false,"given":"Roberta E.","family":"Martin","sequence":"additional","affiliation":[{"name":"Center for Global Discovery and Conservation Science, Arizona State University, Hilo, HI 96720, USA"},{"name":"School of Ocean Futures, Arizona State University, Hilo, HI 96720, USA"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1428","DOI":"10.1016\/j.marpolbul.2009.09.009","article-title":"The coral reef crisis: The critical importance of <350 ppm CO2","volume":"58","author":"Veron","year":"2009","journal-title":"Mar. 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