SFS Annual Meeting

5/20/2019  |   09:00 - 09:15   |  151 G

REACH-SCALE FACTORS AND RIVER NETWORK ATTRIBUTES AFFECT THE LONGITUDINAL DISTRIBUTION OF MACROINVERTEBRATES The River Continuum Concept (RCC) is worldwide considered as a milestone in Stream Ecology because it links the physical attributes of a stream with the availability of food resources (i.e., organic matter and algal biomass), and ultimately with patterns in biodiversity. Up- to downstream gradients in abiotic factors select aquatic taxa, determining progressive shifts in the composition of macroinvertebrate communities along the river continuum. However, the growing attention on the river network perspective has led a several authors to reject the linear and predictable longitudinal changes of the RCC and support, instead, an idea of streams as discontinuum- or patchy-structured systems. In this study quantitative samples of macroinvertebrates were collected in eight sites, located on the main stem of the Pellice stream (Northwestern Italy). The variation in the composition and diversity of macroinvertebrate communities was analyzed in relation to different variables, including in-site factors (e.g., substrate composition), the position along the longitudinal gradient and river network attributes (e.g., distance from tributary junctions). Our results show that benthic invertebrate communities are significantly affected by a combination of factors, acting at both reach and river network scale.

Alberto Doretto (Primary Presenter/Author), University of Piemonte Orientale (Alessandria, Italy), alberto.doretto@uniupo.it;


Elena Piano (Co-Presenter/Co-Author), University of Piemonte Orientale (Italy), elena.piano@uniupo.it;


Elisa Falasco (Co-Presenter/Co-Author), University of Turin (Italy), elisa.falasco@unito.it;


Stefano Fenoglio (Co-Presenter/Co-Author), University of Piemonte Orientale (Italy), stefano.fenoglio@uniupo.it;


Francesca Bona (Co-Presenter/Co-Author), University of Turin (Italy), francesca.bona@unito.it;


Presentation:
This presentation has not yet been uploaded.

5/20/2019  |   09:15 - 09:30   |  151 G

ANTHROPOGENIC FOOD WEB SUBSIDIES IN FRESHWATER SYSTEMS: INTEGRATING WATER INFRASTRUCTURE INTO OUR UNDERSTANDING OF THE RIVER CONTINUUM Recent work has demonstrated the potential importance that large mammals have on the transport of energy and elements between terrestrial and aquatic systems—animals consume resources in one habitat and excrete/egest elements in another. As many species considered in this body of work are of conservation concern, much of this research considers the implications of the loss of this functional role. In contrast, human populations are growing in many regions of the globe. This growth is frequently centered in urban areas, many of which are located on or near rivers. As such, rivers are often recipients of anthropogenically-derived spatial subsides from human waste that may interact with physicochemical factors and produce spatial and temporal variability in community structure and ecosystem processes. However, limited research has considered human waste from a subsidy perspective or integrated the flow anthropogenic subsidies into our conception of the River Continuum. Here, I will discuss the potential influence of anthropogenic subsidies on spatial and temporal variation of ecosystem processes in river networks. Additionally, using a large Mesoamerican river as a case study, I will highlight interactions between anthropogenic waste streams, fish community structure, and nutrient dynamics.

Krista Capps (Primary Presenter/Author), University of Georgia, kcapps@uga.edu;
Research in Krista Capps's lab is dedicated to understanding how anthropogenic activities alter community structure and ecosystem processes (e.g., productivity, decomposition, and biogeochemical cycling) in freshwater ecosystems. Much of her research has focused on the impacts of consumers on basal food resources, community structure, and nutrient dynamics in streams and wetlands. To translate scientific knowledge to actionable outcomes, she actively works with community groups and local, state, and federal employees to develop programs that integrate stakeholder concerns into research planning.

Presentation:
This presentation has not yet been uploaded.

5/20/2019  |   09:30 - 09:45   |  151 G

MICROBES RUN THROUGH IT: THE ROLE OF ALLOCHTHONOUS ORGANIC MATTER IN STRUCTURING STREAM AND RIVER MICROBIAL COMMUNITIES Decomposition of organic matter (OM) is fundamental to nearly all ecosystems and is often mediated by microbes and consumers of the necrobiome. As headwaters receive phototrophically derived allochthonous OM from riparian zones, there is intense microbial and invertebrate processing affecting residual downstream transport. Some systems experience pulses of heterotrophically derived OM as phenological-based (e.g., salmon life cycle) or mass mortality subsidies (e.g., fish kills). Both subsidy types harbor exogenous microbes that are transported to receiving habitats; the fate of which is not well understood. Novel microbes bring intrinsic functions that are also not well documented. Here we used two systems to explore how microbes from allochthonous OM disperse and persist in recipient habitats and become processed or incorporated within consumers. Microbial communities from decomposing leaf litter and carrion were found in both epilithic biofilms and invertebrate consumers in Great Lakes region streams. We also identified different internal microbiomes of stream invertebrate scrapers, shredders and predators from two elevations of contrasting riparian cover along an Alpine river (NW Italy). These studies suggest allochthonous OM contributes new microbes to stream communities, but the function of such biotic subsidies remains unknown.

Courtney Larson (Co-Presenter/Co-Author), U.S. Environmental Protection Agency, larson.courtney@epa.gov;
U.S. EPA

Stefano Fenoglio (Co-Presenter/Co-Author), University of Piemonte Orientale (Italy), stefano.fenoglio@uniupo.it;


Joseph Receveur (Co-Presenter/Co-Author), Michigan State University, receveur@msu.edu;


M. Eric Benbow (Primary Presenter/Author), Michigan State University, benbow@msu.edu;


Presentation:
This presentation has not yet been uploaded.

5/20/2019  |   09:45 - 10:00   |  151 G

IMPACTS OF CLIMATE CHANGE AND DROUGHT OCCURRENCE ON CPOM DEGRADATION IN PREVIOUSLY PERENNIAL ALPINE STREAMS (NW ITALY) Stream ecosystems have been recognized as extremely sensitive to climate change, because of the raising of water temperatures and the disruption of hydrologic cycles. In particular, mountain streams are known to be particularly fragile since highest rates of climate change are occurring above the treeline. The aim of the study was to investigate the functional impact of droughts in three Alpine streams (Po, Pellice and Varaita - NW Italy), which are becoming increasingly intermittent. In particular, using leaf litter bags of chestnut and oak we investigated the CPOM degradation process in both perennial and recently intermittent reaches, by measuring the following: i) mass loss variations; ii) macroinvertebrate colonisation patterns; iii) microbiota communities (fungi and bacteria) involved in the process. We hypothesized that the CPOM decomposition in sites with permanent flow would be driven by a relevant contribution of both macro- and micro-consumers. On the contrary, we expected that CPOM degradation in intermittent sites would be explained primarily by the role of microconsumers. With continued drought conditions and changing CPOM subsidies, the biodiversity, richness and density of colonizer communities could result in altered Alpine stream ecosystems.

Laura Gruppuso (Primary Presenter/Author), University of Turin, laura.gruppuso@unito.it;


Alberto Doretto (Co-Presenter/Co-Author), University of Piemonte Orientale (Alessandria, Italy), alberto.doretto@uniupo.it;


Michela Rappocciolo (Co-Presenter/Co-Author), University of Piemonte Orientale, 20007662@studenti.uniupo.it;


Joseph Receuver (Co-Presenter/Co-Author), University of Maryland, Joseph.receveur@gmail.com;


M. Eric Benbow (Co-Presenter/Co-Author), Michigan State University, benbow@msu.edu;


Francesca Bona (Co-Presenter/Co-Author), University of Turin (Italy), francesca.bona@unito.it;


Stefano Fenoglio (Co-Presenter/Co-Author), University of Piemonte Orientale (Italy), stefano.fenoglio@uniupo.it;


Presentation:
This presentation has not yet been uploaded.

5/20/2019  |   10:00 - 10:15   |  151 G

ABIOTIC CONDITIONS ALTER DRIFTING MACROINVERTEBRATE COMMUNITIES FOLLOWING LAKE STURGEON SPAWNING EVENTS In long-lived iteroparous fish, such as the threatened lake sturgeon (Acipenser fulvescens), high predation during larval stages represents a major bottleneck to population growth. Many of the same predators that feed on larval lake sturgeon also prey upon drifting macroinvertebrates as major portions of their diet. A multi-year study (2010-2018) was conducted to investigate patterns in aquatic insect drift associated with abiotic conditions in sturgeon spawning habitats of the Black River (Cheboygan, MI, USA). Drifting macroinvertebrates and fish were sampled using D-frame drift nets which were set up nightly during periods following sturgeon spawning. We found several strong predictors of drifting macroinvertebrate abundance and biomass across year, including flow rates, temperature and lunar illumination. While some taxa were observed regardless of abiotic conditions, other taxa displayed preferential drifting activity under certain conditions. Variability in the drift of macroinvertebrate species composition and biomass has implications for predator-prey dynamics across trophic levels within the river system including co-distributed prey such as lake sturgeon.

Joseph Receveur (Primary Presenter/Author), Michigan State University, receveur@msu.edu;


Alberto Doretto (Co-Presenter/Co-Author), University of Torino (Italy), alberto.doretto@unito.it;


Edward Baker (Co-Presenter/Co-Author), Michigan DNR, bakere1@michigan.gov;


M. Eric Benbow (Co-Presenter/Co-Author), Michigan State University, benbow@msu.edu;


Kim Scribner (Co-Presenter/Co-Author), Michigan State University, scribne3@msu.edu;


Presentation:
This presentation has not yet been uploaded.

5/20/2019  |   10:15 - 10:30   |  151 G

RIVERINE MICROPLASTIC: LAND-USE EFFECTS AND INTERACTIONS WITH FISH Microplastic is a contaminant of emerging concern globally. Recent studies show microplastic is abundant in freshwater ecosystems, but assessments of microplastic sources, biological interactions, and budgets in freshwaters are lacking. We investigated the links between land-use, spatial scale, seasonality, and microplastic abundance in water and sediment in 9 headwater streams and 8 major rivers throughout Lake Michigan’s watershed. Urban and agricultural land-use were positively related to water column microplastic concentrations across all sites, and watershed forest coverage showed a negative relationship. Microplastic concentration in benthic sediment was 4 to 45 times greater than surface water concentrations. Microplastic concentrations were greater in major tributaries compared to headwater streams and were on average 3 times greater during summer compared to fall and spring. Results show microplastic abundance in freshwater habitats varies across seasons, is influenced by land-use, and deposition to sediment may be a long term microplastic sink. Ongoing work will integrate these data with measurements of seasonal microplastic abundance in common macroinvertebrate and fish taxa, and with assessments of microplastic-associated microbial communities.

Rae McNeish (Primary Presenter/Author), California State University Bakersfield, rae.mcneish@gmail.com;
Dr. McNeish is an early career freshwater ecologist located at California State University, Bakersfield. Her research focuses on terrestrial-aquatic connections and how anthropogenic activities, pollutants, and terrestrial management practices impact freshwater ecosystems. Current research projects are exploring the ecological and biological connections associated with anthropogenic litter and microplastics in the environment while working towards establishing standardized microplastic methodologies.

Lisa Kim (Co-Presenter/Co-Author), Loyola University Chicago, lisahaneulkim@gmail.com;


Sherri Mason (Co-Presenter/Co-Author), State University of New York at Fredonia, mason@fredonia.edu;


John Kelly (Co-Presenter/Co-Author), Loyola University Chicago, Jkelly7@luc.edu;


Timothy Hoellein (Co-Presenter/Co-Author), Loyola University Chicago, thoellein@luc.edu;
Dr. Hoellein is a freshwater ecologist at Loyola University Chicago. His research interests are focused on ecosystem processes and biogeochemistry. His research lab explores these areas in associate with the movement and biological transformation of elements, energy, and pollution in aquatic ecosystems.

Presentation:
This presentation has not yet been uploaded.