Customer Stories

The latest victim of global warming, the Great Barrier Reef (GBR) is under serious threat, and its outlook is dire. The challenge in conserving the Reef has been partly due to the lack of a complete map of the GBR's topography. That may change with an eCognition-based mapping technique that's enabled one project team to produce the world's first-ever topographic map of the GBR. overview Location AUSTRALIA TRANSFORMING THE WAY THE WORLD WORKS TRANSFORMING THE WAY THE WORLD WORKS Since 2007, Dr. Chris Roelfsema, a researcher and lecturer at Queensland University, has been experimenting with satellite data and Trimble eCognition Object-Based Image Analysis (OBIA) software to develop a scalable, coral reef mapping approach. In 2016 he led a successful pilot project that used eCognition to produce topographic and benthic composition maps of 20 GBR reefs. The success and promise of that study led to funding in 2017 to expand the technique across 237 northern GBR reefs that are in dire condition. To map the reefs, Roelfsema used eCognition with satellite image mosaics and integrated ancillary data. eCognition classified geomorphic zones first. Moving from one reef to the next, it analyzed the depth values of the image mosaic and distinguished reefs from non-reefs to create a reef map. The software then differentiated between the shallow reef top and not reef top. Within the identified reef top, it classified shallow geomorphic zones such as reef crest, inner reef flat, outer reef flat and lagoon. Then for the deeper, not-reef zones it used depth, wave and wind information to distinguish exposed and sheltered slopes and plateaus. Once all the geomorphic zones were classified, eCognition used field data and depth characteristics to differentiate benthic habitats such as coral/algae. In total it took eCognition 45 minutes to produce geomorphic and benthic habitat maps for all 237 reefs. Impressed with the mapping results, the GBR Marine Park Authority (GBRMPA) funded Roelfsema to scale the methodology to the GBR's 2,900 reefs. "A DREAM COME TRUE" In early 2019, the GBR Habitat Mapping Project (GBRHM) was launched. A three-year initiative, it aims to develop a comprehensive, seamless map of the GBR, detailing the

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