sustainability Article Spectral Deconvolution for Dimension Reduction and Differentiation of Seagrasses: Case Study of Gulf St. Vincent, South Australia Charnsmorn Hwang 1,*, Chih-Hua Chang 1,2,* , Michael Burch 3, Milena Fernandes 4,5 and Tim Kildea 4 1 Department of Environmental Engineering, National Cheng Kung Chung University, Tainan 701, Taiwan 2 Global Water Quality Research Center, National Cheng Kung University, Tainan 701, Taiwan 3 Department of Ecology and Evolutionary Biology, The University of Adelaide, Adelaide, South Australia 5005, Australia 4 Australian Water Quality Centre, SA Water, Adelaide, South Australia 5000, Australia 5 College of Science and Engineering, Flinders University, Adelaide, South Australia 5001, Australia * Correspondence:
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[email protected] (C.-H.C.); Tel.: +886(6)275-7575 (ext. 65826) (C.-H.C.) Received: 30 May 2019; Accepted: 1 July 2019; Published: 5 July 2019 Abstract: Seagrasses are a vulnerable and declining coastal habitat, which provide shelter and substrate for aquatic microbiota, invertebrates, and fishes. More accurate mapping of seagrasses is imperative for their sustainability but is hindered by the lack of data on reflectance spectra representing the optical signatures of individual species. Objectives of this study are: (1) To determine distinct characteristics of spectral profiles for sand versus three temperate seagrasses (Posidonia, Amphibolis, and Heterozostera); (2) to evaluate the most efficient derivative analysis method of spectral reflectance