The Diatom Web Academy continues...

Sessions are recorded and can be accessed for later viewing. You are invited to join us, wherever you may be, from anywhere around the world.


Tuesday October 26, 2021
10 AM - 11 AM (mountain time, US and Canada)
18:00 Central European Time
Luisa Riato, Oak Ridge Institute for Science and Education Research Fellow at the U.S. EPA Corvallis, Oregon
Genus-level, trait-based multimetric indices for diatom assessment of rivers and streams across the conterminous U.S.

Description: Taxonomic inconsistency in diatom datasets can constrain use of diatoms as biological indicators in aquatic assessments. This talk addresses this problem by developing genus-level, trait-based diatom multimetric indices (MMIs) to assess river and stream condition across the conterminous United States. In contrast to traditional species-level approaches, trait-based approaches can use genus-level data, which is simpler and less-expensive to obtain. For large-scale assessment programs that require multiple taxonomic laboratories to process samples, such as the United States Environmental Protection Agency’s (U.S. EPA’s) National Rivers and Streams Assessment (NRSA), the trait approach can eliminate discrepancies in species-level identification or nomenclature that can render diatom data unreliable. We apply our trait-based MMI within three large ecoregions used by NRSA. We show that trait-based diatom indices constructed on genus-level taxonomy can be effective for large-scale assessments, and may allow programs such as NRSA to retrospectively assess trends in freshwater condition by revisiting older diatom datasets. While the level of taxonomic resolution required for diatom-based assessments is still under debate, our results are supported by other studies that show genus-level identification can provide a robust biotic assessment. Importantly, we do not suggest that species-based approaches should be replaced by genus-level approaches; instead our research shows that trait-based MMI’s offer a suitable alternative when reliable species-level data are not available. Future work will assess the performance of the regional-scale MMIs on state-level datasets.

Target audience: Those interested in incorporating diatoms in freshwater biological assessments, and applying genus-level taxonomy, and trait-based approaches in bioassessments.

Zoom Link:
Meeting ID: 982 3349 0068
Passcode: 834613130
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Tuesday November 9, 2021
10 AM - 11 AM (mountain time, US and Canada)
18:00 Central European Time
Isabel Hong, Central Washington University, Ellensburg, Washington
Diatoms of the intertidal environments of Willapa Bay, WA, USA as a sea-level indicator

Tuesday November 16, 2021
10 AM - 11 AM (mountain time, US and Canada)
18:00 Central European Time
Nicholas Schulte, University of Colorado - Boulder
Application of diatom multi-metric indices to state monitoring data

Tuesday December 7, 2021
10 AM - 11 AM (mountain time, US and Canada)
18:00 Central European Time
Paula Noble University of Nevada, Reno


Martyn Kelly
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Becky Bixby
Looking for light - the role in shaping diatom assemblages

Melissa Vaccarino
Diatoms 101

Aga Pinowska
Microalgae-based biofuels

Sarah Spaulding
The genus Navicula

Franco Tobias and Evelyn Gaiser
Long-term studies of calcareous benthic assemblages, Florida Everglades

Xavier Cortada
The art of diatoms

Patrick Kociolek
Grades and clades

Thomas Frankovich, Florida International University
Evolution and ecology of the secret gardens growing on marine megafaun

Paul Hamilton
The genus Neidium

Eveline Pinseel
Pinnularia borealis
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Elena Jovanoska
The genus Diploneis

Xavier Benito
Is everything everywhere? Community ecology meets biogeography

Sylvia Lee
Keeled diatoms

Kathleen Stoof-Leichsenring
Applications of diatom sedimentary DNA in paleoecology