Discrimination of coral reefs, seagrass meadows, and sand bottom types from space: a Dominican Republic case study

Joseph Luczkovich, Thomas Wagner, Jeffrey Michalek, Richard W Stoffle

Research output: Contribution to journalArticle

59 Scopus citations


In order to monitor changes caused by local and global human actions to a coral reef ecosystem, we ″sea-truthed″ a natural color Landsat Thematic Mapper (TM) image prepared for a coastal region of the northwestern Dominican Republic and recorded average water depth, precise geographical positions; and bottom types (seagrass, 15 sites; coral reef, ten sites; and sand, six sites). There were no significant differences in depth for the bottom type groups. The depths ranged from 0 to 16.1 m (0 to 52.7 ft). Sand > seagrass > coral in mean Landsat digital counts (proportional to radiance) for the three Landsat TM visible bands (TM 1, TM 2, TM 3); sand bottom sites had significantly greater digital counts than seagrass and coral sites in TM 1 only. Mean digital counts of seagrass and coral reefs sites did not differ significantly in any band. A multivariate analysis of variance using all three bands gave similar results. A ratio of the green/blue bands (TM 2/TM 1) showed there was a spectral shift associated with increasing depth but not bottom type. Due to small-scale patchiness( < 30 m by 30 m), seagrass and coral areas were difficult to distinguish, but sandy areas can be distinguished using Landsat TM imagery and our methods.

Original languageEnglish (US)
Pages (from-to)385-389
Number of pages5
JournalPhotogrammetric Engineering and Remote Sensing
Issue number3
Publication statusPublished - Mar 1993
Externally publishedYes


ASJC Scopus subject areas

  • Earth and Planetary Sciences (miscellaneous)
  • Computers in Earth Sciences
  • Earth and Planetary Sciences(all)
  • Environmental Science(all)

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