Coral Reefs Remote Sensing

Background and Aim

Coral reef environments cover relatively less than 1% of the world’s oceans; however, their value to the global community through their services is significant. The submerged and often remote characteristics of these environments make them challenging to map and monitor.

Remote Sensing or Earth Observation offers a unique set of measurement, mapping, monitoring, and modeling tools applied to coral reef environments. These tools are used for:

1. Fundamental ecological studies examining geomorphology, processes, and relationships between living organisms and their physical coral reef environment; and
2. A wide range of government, community, and industry contexts, including but not limited to conservation biology, resource management, fisheries, aquaculture, resilience, restoration, and conservation in coral reef ecosystems.

Remote sensing data sets and analysis techniques provide scale-specific approaches, in spatial and temporal contexts, for measurement and monitoring ecosystems at the individual, population, community, marine and coastal ecosystem, and biosphere levels.

The mostly submerged characteristics of coral reefs and also seagrass habitats require additional considerations with data collection above and underwater and processing of remote-sensing-based products that are specific to these environments. The constantly moving water column due to tides, wind, waves, and currents directly impacts the ability to differentiate features using remote sensing platforms under and above water.

Remote sensing of coral reef habitats needs to be supported by robust work which takes into account the submerged characteristics of these environments. It needs to be a linking field and requires process-based measurements of satellite, airborne, drone, and close-range underwater photography image data sets to develop and validate algorithms and applications for use across the academic, government, community, and industry sectors. These applications are inherently multidisciplinary and require effective collaborations.

This Section on Coral Reef Remote Sensing provides a fast and robust reviewing process on new ideas involving the use of remote sensing to deliver data sets to study these mostly submerged environments. Papers in this Section build the knowledge, applications, and capacity base for advancing our capabilities in a robust, diverse, and equitable manner by encouraging and supporting works that explicitly link field and remote sensing data sets and expertise across a range of disciplines that contribute to the conservation of coral reef and seagrass habitats.

Scope

Examples of the primary coral reef remote sensing challenges that this section will address include:

1. Applications from a range of sensors and scales, spectrometry and fluorometry in laboratory and field; hydro-optical measurements; close range photogrammetry, multi- and hyper-spectral imaging;
2. A range of environmental variables, including photosynthetic efficiency and concentrations of pigments in corals and seagrass; benthic community types; biomass, primary production, concentrations of organic in inorganic material in surrounding waters, along with rugosity, bathymetry, wave climate, hydrodynamics, and geomorphic zones;
3. Coverage across site scale to reef system scales, including under and above water;
4. Integration of variables across scales, as these are essential to enable larger-scale measurement and monitoring of processes on coral reefs and their surrounding environments.