Intertidal biofilm taxonomic group proportion maps derived from AVIRIS-Next Generation 3.7-meter airborne imagery, South San Francisco Bay, California
Description
Microbial biofilm communities are composed of fungi, bacteria, and phytoplankton taxonomic groups (e.g., chlorophytes, diatoms and cyanobacteria), which inhabit the surface of intertidal mudflats. Such biofilms have critical roles in shorebird diets, mudflat stabilization, primary productivity, and carbon storage. These raster datasets represent the likely relative proportion of three biofilm taxonomic groups – chlorophytes, diatoms, and cyanobacteria – located on the mudflats of South San Francisco Bay in Spring 2021, during peak shorebird migration. To produce these datasets, we used a multi-scalar remote sensing approach that coupled in-situ data with data from an ASD field spectrometer, a HySpex VNIR/SWIR imaging spectrometer (5 mm), and the AVIRIS-Next Generation (NG) airborne imaging spectrometer (3.7 m). We used these data to develop and scale algorithms of pigments that are indicators of the taxonomic groups – chlorophytes: chlorophyll-a (chl-a) and chl-b; diatoms: chl-a, fucoxanthin and diadinoxanthin; and cyanobacteria: chl-a and zeaxanthin. Using multiple and single response partial least squares regression, we modeled each pigment with field spectra and scaled models to the South Bay using an AVIRIS-NG image collected on April 15, 2021. Using the resulting pigment indicator maps, we generated maps of the proportions of each taxonomic group within each pixel, which was normalized by mapped chl-a concentrations. Maps created using hyperspectral remote sensing data will support managers’ need to visualize shorebird habitat quality and research on drivers of biofilm quality and quantity.