BIOSCape-Mapping of phytoplankton functional types from space in support of coastal resource management and decision support activities

Lead PI: Jinghui Wu , Dr. Joaquim I Goes , Helga do Rosario Gomes , Grant C. Pitcher, Thomas G. Bornman

Unit Affiliation: Biology and Paleo Environment, Lamont-Doherty Earth Observatory (LDEO)

June 2022 - May 2025
Indian Ocean ; Atlantic Ocean
Project Type: Research

DESCRIPTION: The overarching goal of this NASA funded project is to develop a hyperspectral radiometric method to map the spatial distribution of phytoplankton functional types (PFT) across environmental gradients within St Helena Bay [Namaqua Bioregion], Walker Bay (Agulhas Bioregion] and Algoa Bay [Agulhas Bioregion] of the South African coast. The planned method will take advantage of the unique hyper-spectral remote sensing reflectance (Rrs) signals caused by phytoplankton pigment variability, to detect specific PFTs. This pigment detection method for PFTs will combine new in-situ optical with bio-optical, microscopic, phytoplankton pigment and e-DNA data collections to develop algorithms for PFTs, in particular for detection of HABs using the narrow band hyperspectral datasets from AVIRIS-NG and PRISM that will be flown during the BIOSCape field campaign. Field datasets will be first used to disentangle the optical complexity imparted to bay waters to separate Rrs signatures of phytoplankton communities from those due to other seawater constituents such as mineral particles, colored, dissolved and particulate organic matter. Residual hyperspectral Rrs signals attributable to phytoplankton will be used to detect different pigments essential for discriminating specific PFTs. Our team will work closely with BIOSCape team members to plan the flight lines and ensure that the data from the overflights over coastal waters are minimally impacted by cloud cover, atmospheric aerosols and haze, sun-glint, and atmospheric variability between transects. In addition to the AVIRIS-NG and PRISM data sets, satellite maps of PFTs planned to be generated using multi-spectral data from MODIS-Aqua, Suomi-VIIRS, VIIRS-20 and PACE, will allow us to address 5 hypotheses pertaining to two theme areas: (a) the distribution and abundance of biodiversity in the Greater Cape Floristic Region of South Africa (GCFR) and (c) the feedbacks between global change, biodiversity change, and ecosystem services in the GCFR.