5/24/2016  |   10:30 - 10:45   |  306

TAXONOMIC (IN)CONSISTENCY IN ALGAL BIOASSESSMENT DATA: AN ANALYST’S PERSPECTIVE, AND RESULTS FROM A STATEWIDE STUDY OF NUTRIENT EFFECTS ON DIATOM COMMUNITIES The goal for any algal analyst is to ensure that her data are as accurate and consistent as possible. Issues including analyst experience and access to appropriate resources such as regionally appropriate taxonomic references and quality microscopes may affect the accuracy of a data set. However, even if the taxonomic accuracy of a data set is not perfect, it can still be useful in bioassessment. We present the results of a statewide evaluation of the relative effects of nitrogen and phosphorus on diatom community structure in Wisconsin streams, and discuss the utility of the results despite imperfections in the data.

Gina LaLiberte (Primary Presenter/Author), Wisconsin Department of Natural Resources, gina.laliberte@wisconsin.gov;


Matthew Diebel ( Co-Presenter/Co-Author), Wisconsin Department of Natural Resources, matthew.diebel@wisconsin.gov;


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5/24/2016  |   10:45 - 11:00   |  306

USING PERIPHYTON COMMUNITIES TO INDICATE NUTRIENT LEVELS IN PACIFIC NORTHWEST STREAMS Determining specific sources and impacts of nutrient enrichment in stream ecosystems can be complex and costly. As part of the US Environmental Protection Agency’s Nutrient Scientific Technical Exchange Partnership and Support (N-STEPS) program, we evaluated how well periphyton communities identified during routine biomonitoring relate to stream nutrient concentrations in Oregon (Pacific Northwest, USA). To do this, we compiled 450 paired algal-nutrient samples across the 8 Level-III Ecoregions in Oregon. Periphyton data, including biomass and community metrics, were compared to total nitrogen (TN) and phosphorus (TP) concentrations. Correlations between periphyton biomass (ash free dry mass and chlorophyll a) and nutrient concentrations were weak. In contrast, community composition metrics, including percent diatoms and abundance of nutrient-sensitive species, had strong, nonlinear relationships with TN and TP concentrations. The nature of the relationships also varied by Level-III Ecoregion, with wet ecoregions having more muted relationships between community metrics and nutrient concentrations than dry ones. These results suggest that periphyton community data can focus monitoring and other actions addressing nutrient-related water quality impairments across Pacific Northwest streams.

Daniel Sobota (Primary Presenter/Author), Oregon Department of Environmental Quality, sobota.daniel@deq.state.or.us;


Shannon Hubler ( Co-Presenter/Co-Author), Oregon Department of Environmental Quality, hubler.shannon@deq.state.or.us;


Michael Paul ( Co-Presenter/Co-Author), U.S. Environmental Protection Agency, Paul.Michael@epa.gov;


Rochelle Labiosa ( Co-Presenter/Co-Author), US Environmental Protection Agency, labiosa.rochelle@epa.gov;


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5/24/2016  |   11:00 - 11:15   |  306

EFFECTS OF TAXONOMIC CONSISTENCY ON DIATOM METRIC PERFORMANCE I used three analyses of the 2008-2009 National Rivers and Streams Assessment (NRSA) by the USEPA to evaluate problems with metric performance caused by taxonomic inconsistency. Ten diatom metrics were calculated for the NRSA based on diatom species traits (autecological information) determined in previous studies. First, variability in the 10 metrics was much less between repeat QC counts done by different taxonomists than for counts of different samples from the same site collected at different times. The second analysis found little difference in metric distinction between reference and highly disturbed sites for the same 10 metrics calculated without lumping taxonomy and with lumping of species names at two higher levels. In the third analysis, weighted average (WA) regression models were calculated for TP, TN, pH, and conductivity using the three levels of taxonomic lumping plus genus level taxonomy. These WA metrics performed better at lump level 1 than at lower and higher levels of taxonomic aggregation. My results indicate that taxonomic sources of error in metrics are less than temporal variability in metrics and harmonizing taxonomy can improve metric performance.

Jan Stevenson (Primary Presenter/Author), Michigan State University, rjstev@cns.msu.edu;


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5/24/2016  |   11:15 - 11:30   |  306

DO WE NEED SOFT-BODIED ALGAE AS BIOINDICATORS IN STREAM BIOASSESSMENT? We present an overview of the lessons learned over several years from the large-scale stream bioassessment incorporating benthic soft-bodied algae in the Surface Water Ambient Monitoring Program (SWAMP) of the State Water Control Board. The challenges and appropriate practices associated with the field sampling, laboratory sample processing, and light microscopic species identifications of soft-bodied algae are discussed. Examples of new soft-bodied algal metrics responsive to the generalized stressor, based on locally evaluated indicator species and ecological guilds are provided. Molecular methods for causal assessment, such as nutrient condition, using algal ecological guilds (for instance, N2-fixing cyanobacteria alone, or in combination with red algae and Zygnemataceae) could be developed as more immediate option then the molecular bioassessment of algae community composition. The recent expansion of drought mediated toxin-producing cyanobacteria communities have shown that microscopic methods for monitoring are required, supplemented by molecular toxin assessment. Therefore, the knowledge of soft-bodied algal community composition and structure provides increasingly important information for managing stream ecosystems.

Rosalina Stancheva (Primary Presenter/Author), George Mason University, rchris13@gmu.edu;


Robert Sheath ( Co-Presenter/Co-Author), California State University San Marcos, rsheath@csusm.edu;


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5/24/2016  |   11:30 - 11:45   |  306

STANDARDIZATION AND LONG-TERM TRENDS IN A MULTI-DECADAL PHYTOPLANKTON DATABASE FOR UPPER KLAMATH LAKE, OREGON The Klamath Tribes monitor water quality including phytoplankton in shallow, hypereutrophic Upper Klamath Lake, Oregon, which hosts massive summer blooms of the cyanobacterium Aphanizomenon flos-aquae. Four laboratories analyzed the samples over the study period (1990-present), necessitating an extensive standardization effort prior to data analysis. Inter-lab issues addressed included: differing species identifications, taxonomy updates, varying levels of taxonomic detail (e.g., aggregating to genus vs. species), differing counting units (e.g., enumeration of cells vs. algal units), and different biovolume calculation methods. Standardization was informed by reviewing archived slides; comparing detections and average taxa biovolume for each lab and year; previous taxonomic standardization efforts; interlab quality assurance samples; and graphical evaluation of seasonality. Following standardization, we conducted a preliminary evaluation of long-term trends. Mann-Kendall trend tests suggest a delay in the onset of the early summer Aphanizomenon flos-aquae bloom, as well as increasing biovolume of the toxigenic Microcystis aeruginosa in some late-summer periods. A second phase of the project currently underway will include a more comprehensive analysis of both time-series trends and interaction with environmental variables using multivariate techniques.

Eli Asarian (Primary Presenter/Author), Riverbend Sciences, eli@riverbendsci.com;


Jacob Kann ( Co-Presenter/Co-Author), Aquatic Ecosystem Sciences, jacob@aquatic-ecosciences.com;


Ann St. Amand ( Co-Presenter/Co-Author), PhycoTech, Inc., astamand@phycotech.com;


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5/24/2016  |   11:45 - 12:00   |  306

ASSESSING IMPACTS OF RECENT DROUGHTS ON PERIPHYTON ASSEMBLAGES IN PACIFIC NORTHWEST (WASHINGTON) The Pacific Northwest is often considered a relatively “wet” region, however recent below-average winter precipitation followed by hot/dry summers have led to recurring drought conditions in some areas. Periphyton, especially diatom assemblages, are well-established and valuable indicators of stream ecosystem conditions that are expected to respond to the impacts of drought (e.g. warmer water temperatures, elevated nutrients). We present an assessment of the response of periphyton assemblages and community metrics (species and genera based) in regions of Washington (e.g. East Cascades) that have experienced drought and non-drought years in 2010 to 2014

Clinton Davis (Primary Presenter/Author), Rhithron Associates, Inc., cdavis@rhithron.com;


Ana Burliga ( Co-Presenter/Co-Author), Rhithron Associates, Inc., amiranda@rhithron.com;


Dennis Vander Meer ( Co-Presenter/Co-Author), Rhithron Associates, Inc., dvandermeer@rhithron.com;


Sean Sullivan ( Co-Presenter/Co-Author), Rhithron Associates, Inc., ssullivan@rhithron.com;


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