Monday, June 5, 2017
14:00 - 15:45

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14:00 - 14:15: / 306B CORRELATIONS OF THE COMPOSITION OF ALGAE ASSEMBLAGES TO THE TROPHIC STATE OF MIDDLE TENNESSEE STREAMS

6/05/2017  |   14:00 - 14:15   |  306B

CORRELATIONS OF THE COMPOSITION OF ALGAE ASSEMBLAGES TO THE TROPHIC STATE OF MIDDLE TENNESSEE STREAMS The ecological understanding of algae communities and their compositional response to eutrophication is limited. Therefore, the use of algae for bioassessment is less common relative to fish and macroinvertebrates. In this study, the effects of eutrophication on algae assemblages was analyzed. Eight streams in eight watersheds in Tennessee were sampled to describe the composition of algal assemblages. There were two primary goals of this study: 1) to document the diversity of algae taxa found in Tennessee streams, and 2) to correlate the composition of both, diatom and soft- algae assemblages to the trophic state. We identified 232 soft-algae and diatom taxa. A student’s t-test determined significant seasonal variation in diatom and soft-algae composition between May and August. The algae trophic index (ATI) indicator values for soft-algae taxa were derived from the abundance-weighted average of chlorophyll-a (A-WAchl-a) and the abundance- weighted average of pollution tolerance index (A-WAPTI). The results demonstrate that the composition of algae assemblages, represented in terms of abundance-weighted averages, is an accurate indicator of trophic state.

Molly Grimmett (Primary Presenter/Author), Austin Peay State University, mgrimmett1@my.apsu.edu;


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14:15 - 14:30: / 306B EXAMINATION OF THE EFFECTS OF METALS ON BENTHIC ALGAE IN STREAMS OF DIFFERENT TROPHY USING A FIELD BIOASSAY

6/05/2017  |   14:15 - 14:30   |  306B

EXAMINATION OF THE EFFECTS OF METALS ON BENTHIC ALGAE IN STREAMS OF DIFFERENT TROPHY USING A FIELD BIOASSAY It is difficult to isolate effects of metals and acids in situ in streams impacted by mining. We examined the efficacy of using chemical diffusing substrates (CDS) to determine how acid, Fe3+, Mn2+, Al3+ and nutrient regime interactions affect benthic algae. CDS containing Mn (24 mg/L), Fe (24 mg/L), Al (6.4 mg/L), acid (1.0N H2SO4), Mn+acid, Fe+acid, and Al+acid were deployed in a flow-through system to determine flux from the liquid media. Flux values ranged from 0.5 to 7.4 ug/cm2/day. Five replicates of each CDS type, and a water control, were placed into a eutrophic (ES) and an oligotrophic (OS) stream. In OS, algal cell densities were significantly lower in treatments with acid. Densities were about 5 times higher in ES, but did not differ significantly among treatments. Treatments with acid had significantly lower chlorophyll and higher phaeophytin concentrations in ES. Acid-tolerant taxa were significantly more abundant for treatments with acid in OS but not ES. Algae were more affected by acid than metals. Higher alkalinity and nutrients in ES may have buffered acid effects, reducing impacts on algae.

Dean DeNicola (Primary Presenter/Author), Slippery Rock University, dean.denicola@sru.edu;


Aaron Onufrak ( Co-Presenter/Co-Author), Slippery Rock University, onufrak.2@wright.edu;


Michael Stapleton ( Co-Presenter/Co-Author), Slippery Rock University, michael.stapleton@sru.edu;


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14:30 - 14:45: / 306B PLANKTONIC ALGAE ABUNDANCE AND DIVERSITY IN URBAN STORMWATER PONDS AND NATURAL SHALLOW LAKES

6/05/2017  |   14:30 - 14:45   |  306B

PLANKTONIC ALGAE ABUNDANCE AND DIVERSITY IN URBAN STORMWATER PONDS AND NATURAL SHALLOW LAKES Several studies have provided evidence that stormwater ponds serve as habitats for fauna and flora, despite various hazards imposed by received pollutants. Planktonic algae are some of the organisms which successfully, and in many cases even excessively, inhabit stormwater ponds. The influence of different pollutant loads or pond construction parameters on phytoplankton abundance and diversity is not well examined yet. With this study we aimed to investigate if urban stormwater ponds constitute phytoplankton habitats comparable to those of natural lakes. Ponds from two geographic locations with similar climate conditions – Denmark and Canada, Peterborough – were selected to be compared. Natural shallow lakes in Denmark were chosen to compare natural and artificial water bodies. Sampling was carried out in May, July and September, 2014. The results have shown that stormwater ponds are at least as rich in phytoplankton taxa as natural shallow lakes. No clear relationship between phytoplankton diversity and physical, chemical parameters of the water bodies could be established, likely as a consequence of the number of biotic and abiotic factors acting together in the analyzed environments.

Greta Minelgaite (Primary Presenter/Author), Aalborg University, gm@civil.aau.dk;


Paul C. Frost ( Co-Presenter/Co-Author), Trent University, Peterborough, Ontario, Canada, paulfrost@trentu.ca;


Marguerite A. Xenopoulos ( Co-Presenter/Co-Author), Trent University, mxenopoulos@trentu.ca;


Diana Agnete Stephansen ( Co-Presenter/Co-Author), Aalborg University, das@civil.aau.dk;


Morten Lauge Pedersen ( Co-Presenter/Co-Author), Aalborg University, mlp@civil.aau.dk;


Jes Vollertsen ( Co-Presenter/Co-Author), Aalborg University, jes@civil.aau.dk;


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14:45 - 15:00: / 306B EFFECT OF TEMPORAL CHANGES IN PHOSPHORUS SUPPLY ON STREAM BIOFILMS AND PHOSPHORUS LIMITATION INDICATORS

6/05/2017  |   14:45 - 15:00   |  306B

EFFECT OF TEMPORAL CHANGES IN PHOSPHORUS SUPPLY ON STREAM BIOFILMS AND PHOSPHORUS LIMITATION INDICATORS The effects of phosphorus (P) on freshwater systems is well-studied. However, the influence of storm runoff, sediment dynamics, and autotrophic and heterotrophic microbial metabolism on the P cycle in streams and rivers is poorly understood. The focus of this project was to evaluate how potential indicators of P limitation in stream biofilms in Fishing Creek near Bloomsburg, Pennsylvania respond to temporal changes in P supply. We measured alkaline phosphatase activity (APA), P uptake, biofilm polyphosphate concentrations, biofilm total P, chlorophyll fluorescence, and water column P concentrations twice a week throughout the summer of 2016. Results show a correlation between these indicators of phosphorus limitation and changes in phosphorus supply associated with drought and local storm events. In early summer, during a drought, APA and P uptake levels were high. As the frequency of storm events increased over time, higher streamflow and more sunlight increased chlorophyll fluorescence and P uptake and APA decreased, indicating nutrient saturation within the stream biofilms.

Jennifer Tuomisto (Primary Presenter/Author), Bloomsburg University, jat18435@huskies.bloomu.edu;


Aaron Gordon-Weaver ( Co-Presenter/Co-Author), Bloomsburg University, amg43366@huskies.bloomu.edu;


Steven Rier ( Co-Presenter/Co-Author), Bloomsburg University, srier@bloomu.edu;


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15:00 - 15:15: / 306B EXAMINING THE ALGAL COMMUNITY TO UNDERSTAND EUTROPHICATION IN THE HIGHLY TURBID INTERNATIONAL RED RIVER OF THE NORTH

6/05/2017  |   15:00 - 15:15   |  306B

EXAMINING THE ALGAL COMMUNITY TO UNDERSTAND EUTROPHICATION IN THE HIGHLY TURBID INTERNATIONAL RED RIVER OF THE NORTH The International Red River Board (IRRB) identified excess nutrients as an important issue in the Red River of the North. The IRRB determined that the best approach to developing nutrient targets for Red River of the North (RRN) would be to understand the biological stressor-responses for nutrients, suspended sediments, and other parameters. A lack of data prompted the development of a plan for collecting periphyton, phytoplankton, and water quality data from 30 sites from the headwater to the mouth of the RRN. Overall, a stressor effect from excess nutrients was documented for both the quantity and quality of the algal community and observed throughout the gradient of the river though turbidity effects were identified. The response of the periphyton community to the nutrient gradient resulted in delineating nutrient targets of 0.15 milligrams per liter (mg/L) for TP and 1.15 mg/L for TN as nutrient criteria for the Red River of the North. Exploration of watershed effects in the stressor-response model indicate anthropogenic disturbances may be more critical than water quality parameters in determining algae variance.

Tony Miller (Primary Presenter/Author), Beaver Creek Hydrology, tony@beavercreekhydrology.com;


Julie Blackburn ( Co-Presenter/Co-Author), RESPEC, julie.blackburn@respec.com;


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15:15 - 15:30: / 306B THE TRADE-OFF BETWEEN NUTRIENT RELEASE AND UPTAKE OF NATIVE AND EXOTIC SUBMERGED MACROPHYTES DURING WATER LEVEL FLUCTUATIONS

6/05/2017  |   15:15 - 15:30   |  306B

THE TRADE-OFF BETWEEN NUTRIENT RELEASE AND UPTAKE OF NATIVE AND EXOTIC SUBMERGED MACROPHYTES DURING WATER LEVEL FLUCTUATIONS Water level drawdown followed by rewetting can shift macrophytes from a nutrient sink to a source thus changing nutrient dynamics and/or causing water quality problems in shallow lakes or reservoirs. This could be a particular issue under global climate change with more frequent droughts or floods. However, there is limited research about the role of macrophytes on nutrient dynamics during water level fluctuations (WLFs). This study examined the trade-off between nutrient release and uptake of two native and exotic submerged macrophytes during WLFs. Our results showed that the nitrogen release from macrophyte decomposition could be balanced out by nitrogen uptake from the same biomass of living macrophytes, but only 40% would be balanced out for phosphorus. Cabomba caroliniana, as an invasive species in Australia, resulted in higher nutrient release and lower water column N:P ratios compared with native Hydrilla verticillata, coinciding with higher water column chlorophyll a concentrations. Desiccated sediments increased the nutrient availability after rewetting, but also the nutrient uptake ability of living macrophytes. The results of this study will provide new insights into the role of macrophytes on nutrient dynamics during WLFs, especially for the P-deficient lentic ecosystems.

Jing Lu (Primary Presenter/Author), Australian Rivers Institute, jing.lu3@griffithuni.edu.au;


Stuart Bunn ( Co-Presenter/Co-Author), Australian Rivers Institute, Griffith University, Australia, s.bunn@griffith.edu.au;


Michele Burford ( Co-Presenter/Co-Author), Australian Rivers Institute, Griffith University, Queensland, Australi, m.burford@griffith.edu.au;


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15:30 - 15:45: / 306B NITROGEN AND PHOSPHORUS HAVE DIFFERENT EFFECTS AT THE TOP AND BOTTOM OF STREAM FOOD WEBS

6/05/2017  |   15:30 - 15:45   |  306B

NITROGEN AND PHOSPHORUS HAVE DIFFERENT EFFECTS AT THE TOP AND BOTTOM OF STREAM FOOD WEBS Causal relationships between excess nutrients and ecological responses that include diverse components of stream ecosystems are needed to effectively address nutrient pollution. Characterizing ecosystem-level nutrient limitation requires identifying the relative control of specific nutrient stressors (nitrogen [N] and/or phosphorus [P]) among ecosystem compartments. We used laboratory, mesocosm, and whole-stream studies to determine the response of organisms and processes to gradients in N vs P concentrations. From microorganisms to vertebrate predators, we detected differential trophic-level responses to streamwater N compared to P. We found greater responses to N than to P by fungi (2.2-15x, production) and algae (6-15x, chl-a; 3.3x, biomass) at the base of the food web, but greater responses to P than to N of macroinvertebrates (1.1-2.5x, production) and salamanders (1.1-1.6x, growth) at the top of the food web. Litter decomposition rates, which integrate microbial and macroinvertebrate processing, were limited more equally by both N and P. Our results show the complex nature of nutrient limitation among organisms across multiple trophic levels that need to be considered in establishing effective nutrient criteria to protect and restore aquatic ecosystems.

Amy D. Rosemond (Primary Presenter/Author), University of Georgia, rosemond@uga.edu;


Jonathan P Benstead ( Co-Presenter/Co-Author), The University of Alabama, jbenstead@ua.edu;


John C. Maerz ( Co-Presenter/Co-Author), University of Georgia, jcmaerz@uga.edu;


Vlad Gulis ( Co-Presenter/Co-Author), Coastal Carolina University, vgulis@coastal.edu;


Phillip Bumpers ( Co-Presenter/Co-Author), Odum School of Ecology, University of Georgia, bumpersp@gmail.com;


David W. P. Manning ( Co-Presenter/Co-Author), The Ohio State University, manning.413@osu.edu;


John S. Kominoski ( Co-Presenter/Co-Author), Florida International University, jkominoski@gmail.com;


Lee Demi ( Co-Presenter/Co-Author), University of Alabama, mickdemi@yahoo.com;


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