The Diatom Web Academy has been providing opportunities for our diatom community to gather since February 2020. Hosted by the Society for Freshwater Science (SFS) Diatom Taxonomic Certification Committee, Web Academy presentations during COVID-19 have been biweekly to promote frequent opportunities for diatomists from around the world to meet and exchange current research, taxonomic strategies, and learn tools needed for SFS diatom taxonomic certification.

Our most recent Academy presentation highlighted efforts in the State of California to use diatoms and soft algae for wadeable stream bioassessment. Drs Susie Theroux and Raphael Mazor from the Southern California Coastal Water Research Project (SCCWRP) presented their work to develop and test multi-metric indices (MMI) using diatoms, soft algae, and a hybrid model to assess biological condition and stressor gradients in California streams. While soft algae could not pass their demanding performance criteria, the diatom MMI and a hybrid diatom-soft algae MMI showed excellent predictive value and have been adopted into California’s suite of indices for stream assessment. Their work will also be highlighted in an upcoming article in Ecological Indicators.

As with all Diatom Web Academy presentations, you can always access a recording of the California Algal Assessment webinar.

But the work is not done. Molecular methods hold promise to open up new avenues of bioassessment in California and worldwide. The SCCWRP is focusing on developing sampling protocols, testing multiple gene sequences, and comparing index performance using DNA barcodes against traditional morphological assessments. Regardless of how the state moves forward the goal of the program remains the same—to use biomonitoring data to get actionable information.

The Diatom Web Academy continues. Join fellow diatomists on August 4 for Dr. Paula Furey speaking on taxonomy and identification in “The genus Eunotia” and Dr. Victoria Chraibi and Shelly Wu presenting “Golden(-brown) Opportunities: Diatoms in Education” on August 18.

Additional Resources:

California bioassessment protocols
Stancheva and Sheath 2016
Fetscher et al. 2013