Mapping kelp biomass using Earth observation in Australia

Image provided by Gillian Rowan: Aerial view of a dense Giant Kelp forest canopy located near Wainui, Canterbury, New Zealand. 

EORC doctoral candidate Gillian Rowan recently travelled to New Zealand’s South Island to collect field data. Her research is funded by CRC-SmartSAT and  focuses on developing the knowledge, tools, and methods needed to map kelp biomass using Earth Observation in Australia.

Image provided by Gillian Rowan: Dense forest canopies of Giant Kelp fringe the coastline off Wainui, Canterbury, New Zealand. A nearby kelp harvesting boat highlights the large size of the macroalgae.

Gillian collected drone imagery of the thick Giant Kelp (Macrocystis sp.) forests that dominate the waters just offshore, the fringing forests of Bull Kelp (Ecklonia sp.) that line the coasts, and an aquaculture operation growing both kelp and blue pearls. She also collected spectral reflectance measurements of a wide range of kelps, macroalgae, and terrestrial materials using one of the EORC’s ASD spectrometers.

Gillian aims to use this collection of drone imagery to later validate satellite maps of kelp extent and biomass estimates. The spectral data, meanwhile, will feed into a separability analysis and subsequent radiative transfer modelling. Her preliminary results will be presented as a poster at the 2024 Australian Marine Sciences Association in Hobart in September.

The trip was made possible through incredibly generous collaborations with local commercial operators Kelp Blue, a kelp farming organisation, and NZ Kelp, the country’s biggest wild kelp harvester.

This project is funded by SmartSAT Cooperative Research Centre.