5/19/2015  |   13:30 - 13:45   |  103C

RECONSIDERING THE PROBLEM OF DIATOM ASSESSMENT OF STREAMS IN AGRICULTURALLY DOMINATED REGIONS Assessment of ecological condition in agriculturally dominated regions has been problematic when using diatom assemblages. Little difference was observed between reference and highly disturbed sites in the USEPA’s National Rivers and Streams Assessment (NRSA). Multiple studies show diatoms respond more to nutrients in low than high ranges of nutrient concentrations. In addition, criteria for reference sites are often relaxed for agriculturally dominated ecoregions, which results in greater variation in levels of human disturbance and nutrient concentrations. That variation in the NRSA spanned the range of sensitive diatom response. However, responses of diatoms along the entire nutrient concentration and human disturbance gradients were great. A modeled MMI using land use helped distinguish minimally disturbed and highly disturbed sites. In addition, refined metrics that emphasize taxa responding to intermediate and high concentrations of nutrients improved assessment sensitivities in agriculturally dominated regions. These results indicate that different metrics can be used to aid distinguishing reference and disturbed sites in agriculturally dominated regions, but stricter definitions for reference conditions (which would also allow a consistent national-scale definition of reference condition) would also aid assessment.

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

5/19/2015  |   13:45 - 14:00   |  103C

DIATOM BIODIVERSITY IN MEDITERRANEAN STREAMS AND ITS POTENTIAL FOR ENVIRONMENTAL ASSESSMENTS: A CASE STUDY FROM THE ISLAND OF CYPRUS Mediterranean streams are highly-stressed environments, mainly because of the wide seasonal fluctuation in water quantity. This natural pressure (which may be exacerbated by climate change) requires organisms to be specially-adapted, and is a significant challenge when establishing efficient assessment methods. We studied environmental parameters (ecomorphology, detailed hydrological background, physical and chemical variables) and diatom assemblages in almost 200 stations in a Cypriot stream network covering an area of about 5550 km2. The detailed taxonomic analysis was carried out using the latest taxonomic concepts. More than 350 taxa belonging to more than 70 genera were identified. Many interesting taxa were found, and several species new to science were discovered and characterized from both taxonomic and ecological standpoints. A comprehensive comparison with the somewhat-sparse literature allowed us to use this large and taxonomically-homogeneous database to point out relevant features of Mediterranean stream diatom assemblages. The diatom data were further analyzed from different perspectives (assemblage composition, diversity and taxonomic structure, natural and anthropogenic drivers, stream types etc.), with the objective of refining ecological assessments.

Marco Cantonati (Primary Presenter/Author), Museo delle Scienze - MUSE, Limnology and Phycology Research Unit, marco.cantonati@muse.it;


Martyn Kelly (Co-Presenter/Co-Author), Bowburn Consultancy, Durham, UK, MGKelly@bowburn-consultancy.co.uk;


David Armanini (Co-Presenter/Co-Author), Western University & Canadian Rivers Institute, d.armanini@protheagroup.com;


Horst Lange-Bertalot (Co-Presenter/Co-Author), University of Frankfurt, Biologicum, Institute for Ecology, Evolution, Diversity, lange-bertalot@gmx.net;


Nicola Angeli (Co-Presenter/Co-Author), Museo delle Scienze - MUSE, Limnology and Phycology Research Unit, nicola.angeli@muse.it;


Daniele Demartini (Co-Presenter/Co-Author), Prothea Srl, Milano, Italy, d.demartini@protheagroup.com;


Gerald Dörflinger (Co-Presenter/Co-Author), Water Development Department, Nicosia, Republic of Cyprus, gdorflinger@wdd.moa.gov.cy;

5/19/2015  |   14:00 - 14:15   |  103C

SPATIAL AND TEMPORAL VARIATION OF PERIPHYTON ASSEMBLAGES AND ASSOCIATED ENVIRONMENTAL CONDITIONS IN THE KLAMATH RIVER (2004-2013), CALIFORNIA, USA Poor water quality conditions in the Klamath River (California, USA) are associated with low dissolved oxygen and high pH as a result of photosynthesis and respiration by periphyton, aquatic plants, and phytoplankton. To examine spatial and temporal patterns in periphyton assemblages, we analyzed samples collected during summer (May-August) and fall (September-November) of nine years (2004, 2006-2013) from 11 sites (n=398) in Klamath River and its largest tributary, Trinity River. Periphyton assemblages were dominated by diatoms (average 92.5% of samples relative biovolume), followed by cyanobacteria (6.0%), and green algae (1.5%). Periphyton assemblages showed clear longitudinal (i.e., upstream vs. downstream) and seasonal patterns (i.e., May-June vs July-October) in species composition. These patterns were associated with a seasonal gradient from low temperature and high flow (i.e., spring and early summer) to high temperature and low flow (i.e., late summer and fall) conditions. Nutrients defined a second longitudinal gradient from upstream nutrient-rich sites to downstream sites with lower nutrient concentrations. This long-term dataset will inform river management decisions such as reducing upstream nutrient loads, setting flow regimes, and potential dam removals.

Nadia Gillett (Primary Presenter/Author), Portland State University, nadezhds@pdx.edu;


Yangdong Pan (Co-Presenter/Co-Author), Portand State University, bwyp@pdx.edu ;


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


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

5/19/2015  |   14:15 - 14:30   |  103C

NMR-BASED METABOLOMICS OF CRAYFISH AS A BIOINDICATOR OF ECOSYSTEM HEALTH OF STREAMS IN SOUTHERN MANITOBA Nutrient losses and contaminants from human activities to aquatic ecosystems in southern Manitoba are a serious threat to ecological integrity of these waterways. Metabolomics is the quantification and characterization of small molecules called metabolites, which are derived from normal processes within a cell, tissue or biofluid. Environmental metabolomics characterizes the biochemical products of interactions between living organisms and their environment. Therefore, environmental metabolomics has the potential to assess how environmental stressors (e.g., pesticides, pharmaceuticals, nutrients) affect the biological health of an exposed organism and/or identify biomarkers of stress. Using NMR-based metabolomics, we evaluated if the metabolome (the set of all detected small molecules) of northern crayfish (Orconectes virilis), could be used as a bioindicator of environmental exposure to stressors associated with agricultural and rural land use activities. Indicator potential was assessed based on the strength of association between the crayfish metabolome and human activity gradients of agricultural and human wastewater treatment activities. Results of this study will be used to inform future studies aimed at evaluating and calibrating the crayfish metabolome to serve as a diagnostic indicator of environmental stressors.

Robert B. Brua (Primary Presenter/Author), Environment and Climate Change Canada, 11 Innovation Boulevard, Saskatoon, SK, S7N 3H5, bob.brua@canada.ca;


Adam G. Yates (Co-Presenter/Co-Author), Western University & Canadian Rivers Institute, adam.yates@uwo.ca;


Joseph M. Culp (Co-Presenter/Co-Author), Environment Canada & Canadian Rivers Institute, Department of Biology, University of New Brunwsick, P.O. Box 4400, Fredericton, NB, E3B 5A3, jculp@unb.ca;

5/19/2015  |   14:30 - 14:45   |  103C

COMPARISON OF BENTHOS AND PLANKTON FOR SELECTED AOC AND NON-AOC RIVERS AND HARBORS, WESTERN LAKE MICHIGAN To inform management decisions regarding removal of Beneficial Use Impairments for “Degradation of Benthos” and “Degradation of Plankton” at Wisconsin’s Lake Michigan Areas of Concern (AOCs), benthos and plankton were collected at four AOCs and six non-AOCs during three seasons in 2012 and 2014. The AOCs are the Lower Menominee River, Lower Green Bay—Fox River, Sheboygan River, and Milwaukee Estuary; each AOC was paired with two non-AOCs of similar size and land use. Taxonomic richness, diversity, and Index of Biotic Integrity (IBI, benthic invertebrates only) were compared between an AOC and 1) all non-AOCs for each seasonal sample, 2) two paired non-AOCs for each seasonal sample, and 3) two paired non-AOCs across all seasons. Results indicate the Lower Menominee River AOC was deemed degraded for benthos IBI; Milwaukee Estuary AOC (Milwaukee and Menomonee Rivers) was degraded for benthos IBI and richness; Fox and Milwaukee Rivers were deemed degraded for zooplankton richness. No AOCs were deemed degraded in 2012 for phytoplankton richness or diversity in comparison to non-AOC sites, possibly due to tolerant taxa. We await 2014 data for comparison.

Barbara Scudder Eikenberry (Primary Presenter/Author), U.S. Geological Survey, beikenberry@usgs.gov;


Amanda Bell (Co-Presenter/Co-Author), U.S. Geological Survey, ahbell@usgs.gov;


Hayley Templar (Co-Presenter/Co-Author), U.S. Geological Survey, htemplar@usgs.gov;


Daniel Burns (Co-Presenter/Co-Author), U.S. Geological Survey, dburns@usgs.gov;

5/19/2015  |   14:45 - 15:00   |  103C

STREAM WATER AND PERIPHYTON CARBON AND NITROGEN STABLE ISOTOPES INDICATE INSUFFICIENT PROTECTION FROM AGRICULTURAL INFLUENCES Stable isotopes are increasingly used as indicators of environmental disturbance. We examined the use of d13C and d15N of stream water and periphyton to determine the effectiveness of Best Management Practices (BMPs) used to mitigate agricultural disturbance in headwater streams in NY State. Stream water and periphyton were collected from 20 streams in four categories: recently applied, long-standing BMP treatments, lacking BMPs, and reference streams. Stream water and periphyton were sampled April through November 2013 and analyzed for ?13C and ?15N content. Aqueous and periphytic ?13C in agricultural streams was 13.4% and 12.2%, respectively, greater than in reference streams, with no difference between BMP categories. Average difference of agricultural water ?15N values was 33.9% greater than reference streams, but varied little between BMP categories. Average difference of agricultural periphyton d15N was 48.1% greater than reference periphyton, which indicates elevated N inputs from the landscape, despite BMP presence. These results indicate a significant effect of agriculture on stream water and periphyton biochemical properties, despite BMP mitigation. This study suggests that current agricultural mitigation steps have not been fully effective at remediation.

Sarah Whorley (Primary Presenter/Author), Daemen University, swhorley@daemen.edu;


John Wehr (Co-Presenter/Co-Author), Louis Calder Center - Fordham University, wehr@fordham.edu;
Professor of Biology at the Louis Calder Center, the biological field station of Fordham University. Directs freshwater ecology research lab. Supervised graduate, undergraduate and high school students in independent research. - Mentored 11 Masters and 7 PhD theses Editor, Freshwater Algae of North America (Academic Press) Specialties: - Phytoplankton and benthic algal identification - Phycology - Biostatistics - Stream ecology - Water chemistry