S01: Water Quantity and Quality Impacts of Unconventional Fossil Fuel Development on Our Freshwater Futures

Rapid development of unconventional shale oil and gas resources over the last two decades has generated concern about the impacts on quantity and quality of freshwater resources. Potential risk to surface and groundwater exacerbate concerns over water security in places where water resources are already over-allocated. This session will highlight recent and ongoing research investigating the impacts of shale oil and gas development on surface and groundwater resources and the interaction of the two within the context of shale oil/gas development. Regional experts will describe impacts and challenges unique to their region. To date, development of these resources has outpaced scientific understanding of the impacts, but it is imperative that these impacts be understood to allow for mitigations measures to be put in place and to adjust for this type of development in designing our freshwater futures.

S02: Urban streams, aquatic ecology, and stormwater engineering: How do we encourage integration, opportunities and collaboration in an era of green infrastructure innovation?

Urban Ecology has seen many advances over the last few decades by fully incorporating the behaviors and structures of people into ecological theory and research. The current nexus of ecohydrological and socio-ecological research offers opportunities for a unique, productive aquatic ecological research agenda within a context of rapidly expanding networks of engineered green infrastructure (GSI) in a socio-ecohydrological matrix. Engineered facilities are rapidly growing, due to large mandated programs dedicated to the management and treatment of urban runoff (e.g., TMDLs, MS4, etc.). The well of fundamental knowledge of ecohydrological processes needed to guide the design of "more natural" GSI is potentially deep, but resides mostly outside the engineering and regulatory community. It is likely that both ecologists and engineers would mutually benefit by collaborating to adapt ecohydrological processes to the unique flowpaths, connectivity, and gray infrastructure of the urban hydrosphere. This session seeks to encourage discussion and collaboration among many fields, in particular aquatic ecology and environmental engineering to explore how a better understanding of an ecology "of and for" the city through a multidisciplinary, multi-objective approach could serve science as well as applied stormwater engineering). Interest in natural ecosystem processes for GSI engineering design is growing, and the time is right for dialogues between aquatic ecologists and engineers. Through collaboration, ecologists could use and contribute to GSI research while GSI design and practice could access a rich diversity of ecohydrological processes, advancing urban aquatic science and expanding GSI capabilities and sustainability during a time of rapid urbanization.

S03: Stressing the 'Eco' in Freshwater Ecotoxicology

It is inherently difficult to capture environmental complexity in laboratory-based experiments of organismal or community-level responses to ecological stressors. The majority of freshwater ecotoxicology studies have incorporated ecology into traditional toxicology studies by focusing on the effects of contaminants on organisms from a structural perspective with few studies concerning changes in community or functional ecosystem parameters. Ecotoxicologists are motivated to understand underlying response mechanisms but do so using stressor concentrations far exceeding those measured in natural systems. Recognizing that such studies provide limited insight about potential ecosystem responses to stressors, the fields of freshwater ecology and environmental toxicology are increasingly emphasizing the need for research efforts that reflect ecosystem complexity. In this session, we plan to highlight research that lies at the intersection of environmental toxicology and freshwater ecology. Selected speakers will present recent work bridging these fields, improving our understanding of stressed freshwater ecosystems. Ideal talks will feature field or mesocosm-based studies or statistical methodologies for interdisciplinary ecosystem research. This session will include case-studies illustrating the challenge of studying system complexity and stressing the benefits of a top-down approach where new mechanistic questions are generated from field and mesocosm-based experiments and subsequently addressed in the lab. These talks will call attention to the need for a holistic understanding of freshwater ecosystem processes in order to improve design and management strategies that serve to protect their health and move the field of freshwater ecotoxicology forward.

S04: Natural and Constructed Wetlands – improving water quality and watershed health

Natural and constructed wetlands have been lauded for years as important ecosystems to protect water quality. High biological productivity and the ability to periodically store water for extended periods create unique aerobic and anaerobic conditions ideal for transformations and storage of many pollutants. Most scientists and engineers will freely admit that wetlands are great systems to treat contaminated water. Public perception of wetlands for water quality improvement is also reasonably good. So why aren't they used more? Wetland restoration and the use of wetlands for urban stormwater management has increased in the past 2 decades, but the use of wetlands to treat or polish more high-strength wastewater has not been as widespread in many U.S regions. For example, only 6-8 constructed wetlands for municipal and industrial wastewater are currently operational in N.C. Funding for research and implementation of constructed wetlands for municipal wastewater treatment have diminished. Is it because people have lost faith in these systems, or are they being held back by perception, legal, or operational issues? This technical session will task experts to identify challenges and opportunities faced with wetlands and water quality. Speakers are encouraged to present an overview of their experience that will hopefully blend research and case studies with their philosophy on if and how wetlands should be managed and constructed in the future to improve water quality.

S05: Social-Ecological Freshwater Systems

Maintaining sustainable water supplies is a global issue. In the U.S., there is concern about future water supplies because of growing human populations and increases in drought frequency and magnitude linked to climate change (Pederson et al. 2012). Tradeoffs between water security for human needs and freshwater ecosystem health will only become more challenging in the future with increasing human demand for freshwater coupled with impending shifts in the duration and frequency of extreme climatic events and associated alterations in stream flows. This current social-ecological crises requires of new interdisciplinary and holistic conceptual approaches. Recognizing that biodiversity preservation is about species and ecosystems as much as societies suggests an interesting change in the way we approach human-environment interactions. Therefore, there is a real challenge for recognizing that societies are highly interconnected with the biophysical life-support system, thus conforming social-ecological systems or coupled human and natural systems.

S06: Advances in research to conserve and restore native freshwater mollusks

Freshwater mollusks (mussels and snails) are among the most imperiled groups of animals. Questions on how to conserve them has generated considerable research in the past few decades. Native freshwater mussels are an integral part of riverine systems as they stabilize substrates, cycle nutrients, provide substrate for colonization of other plants and animals, and serve as a food source for fish and mammals. Although species richness and density have declined over the past few centuries in many river systems, research into the science supporting their conservation and restoration has substantially increased. Freshwater snails occur in a variety of habitats, however, many species are restricted to a single location, which makes conservation efforts challenging. In the past few decades, the mollusk community has made considerable progress in the fields of sampling, taxonomy, conservation genetics, propagation, ecosystem services, life history, habitat requirements, and water quality requirements, which has provided needed information to conserve this diverse group. This session will highlight some of the major advances in this field and suggest directions for future research that will benefit scientists and mangers working with imperiled mollusks.

S07: Conducting freshwater science with open-source, inexpensive technologies

Open-source, inexpensive technologies are becoming more commonplace in labs around the world. The adoption of open-source software (R computing language, Python, etc.) has grown rapidly. However, the use of open-source hardware (Arduino and others) has not gained significant traction within the water research community. Open-source hardware has remained within the hobbyist or DIY (Do-It-Yourself) communities. This is likely due to the initial learning curve of working with open source hardware as well as their availability. There are increasing resources available on the internet (Arduino.cc, EnviroDIY.org, Publiclab.org) that facilitate lowering that curve as well as several retailers of open-source hardware (Adafruit.com, Sparkfun.com, etc.) working to spread adoption of these technologies. We propose a special session on open-source, inexpensive technologies that are being used for water resource studies around the world. By bringing researchers together who are working on these technologies, we hope to demonstrate what is currently capable while providing the impetus for further innovation and adoption.

S08: Ecosystem Services and Pricing Water for Freshwater Conservation

Freshwater ecosystem services provide multiple benefits for people and nature. A balance of needs is important so that freshwater can provide the necessary services that society and nature require. Institutional and infrastructure needs have to be in place to perform ecosystem services. Finding and detecting leaks in freshwater supply systems is one step in reducing freshwater demands. Raising water rates so people will conserve more is another step in reducing freshwater demand. A solution oriented approach would be incorporating all users of freshwater from one watershed and finding ways to maximize efficiencies without wasting water. All water users need to pay higher rates for water based on the amount of water used. This will offer conservation incentives to those whose demand on the freshwater ecosystem is greatest, therefore giving those utilizing water a greater stake in that watershed. When electricity rates increased, people conserved kilowatt usage so this principle should carry over to water use. People and nature will benefit from freshwater ecosystem services, as well as pricing water appropriately to encourage conservation of our most precious natural resource.

S09: The importance of environmental gradients for the advance of tropical stream ecology

Environmental gradients are often used in ecology as tools to assess the effects of environmental change on ecosystem characteristics and processes. Gradients can be used as proxies that allow us to understand the effects of past (e.g., land use) or future (e.g., elevation and temperature) change in the environment. Latitudinal and elevation gradients, for example, have provided valuable information on biodiversity patterns and species distribution. In the tropics, the study of environmental gradients has a long history and new tools and approaches are being proposed to understand tropical stream biodiversity and ecology. In this session, we will explore the contribution of studies along environmental gradients to stream ecology with particular emphasis to tropical streams. Presentation will include studies working on variours taxonomic groups and studies focusing on different ecosystem processes along gradients. We use a broad definition for environmental gradient, to allow for a variety of examples to be included.

S10: Understanding and predicting the effects of climate change on lake and stream fishes

Climate change adaptation strategies require predictions of how systems are likely to change under future conditions. To date, projected effects of climate change on freshwater fishes involve multiple steps, including 1. Linking contemporary climate to fish habitat and demographics; 2. Projecting changes in fish habitat under climate change, and 3. Projecting future fish status as a result of these changes. Numerous approaches exist for each of these steps, including both statistical and mechanistic models, each with different sources of uncertainty and limitations. In order to be most useful to decision-makers, a suite of approaches should be used in order to identify consistencies and uncertainties in projected future states. This session focuses on projected impacts of climate change on both lakes and streams to develop an integrated picture of climate change impacts on freshwater fishes. We invite speakers focusing on diverse topics including stream flow and temperature models, lake temperature models, statistical models of fish response to climate change, mechanistic/physiological models of fish response to climate change, aquatic connectivity, biotic interactions and food webs, invasive species, and approaches to identify or design refugia. We will highlight especially multiple modes of inquiry for understanding and predicting the effects of climate change on freshwater systems. Speakers are encouraged explicitly link research results to management strategies designed to facilitate adaptation to climate change, and to highlight key uncertainties in their results. We will specifically engage speakers working in diverse sectors to present a multi-faceted view of science enabling climate adaptation in freshwater systems.

S11: Scholarship of Teaching and Learning in Freshwater Science

Typical science courses emphasize memorizing facts when learning is actually driven by being observant, thinking, linking concepts, and asking good questions. As a response to our nation's "leaky STEM pipeline," and the subsequent AAAS Report: Vision and change in undergraduate biology education: a call to action (2011), the science class room is changing. Biology education is making more connections across curriculum, clarifying relevance to the 'real-world,' and placing less emphasis on memorization (AAAS 2011). Further, there has been a rise of practitioners (discipline specific experts) who are now contributing their best teaching practices as a recognized form of scholarship. Those with discipline specific research are now developing inquiry based activities that increase intellectual engagement and foster deep understanding. We propose a special session focused on teaching (e.g. techniques, goals, troubleshooting, modules, experiences) all levels of freshwater science. We hope to encourage SFS members to contribute inquiry activities and resources to be used in the classroom/lab, and ultimately, increase the availability of educational outreach materials that we offer as a society (which are currently scarce). Additionally, we’d like to promote the Scholarship of Teaching and Learning in our field and society so that freshwater science can be represented and explored in all levels of education and outreach. Engaging and effectively educating students in the classroom and laboratory about freshwater science is the foundation of Designing our Freshwater Futures.

S12: Challenges, insights, and opportunities in crayfish conservation and ecology

The influence of crayfish on instream process, species displacement, organic matter and sediment processing, and maintenance of biodiversity has been well documented. Recently, there has been renewed interest in understanding the phylogeny, distribution, life history, and population structure of many lesser-known taxa. Crayfish species are still being discovered and described while familiar invasive crayfish continue to plague ecosystems worldwide. What we are learning is that we have a lot left to learn about these enigmatic organisms: species-specific effects are quite common, most life history descriptions are best guesses, physiological and population constraints are largely unknown. The causes of conservation concern for most species however are strikingly similar – habitat degradation, taxonomic ambiguity, narrow and/or nebulous distributions, and unknown life histories are common themes. These are not necessarily crayfish-specific problems however, thus models providing viable solutions likely exist outside of the realm of astacology, opening the door for highly integrative and collaborative approaches. This session will serve to highlight recent case-studies and perspectives with a focus on approaches that merge novel and established tools for conservation, enhance ecological understanding, and in turn help bring crayfishes to the forefront of freshwater conservation efforts for practitioners, managers, decision-makers, and researchers. The perspectives of early-career scientists are particularly encouraged, and all speakers are challenged to provide a broad context and articulate how their study contributes solutions to the ‘crayfish conservation problem’. The session will be structured to highlight critical steps and information needed to guide development of a coordinated, integrative, and comprehensive crayfish conservation plan.

S13: Freshwater protected areas: optimizing conservation of functional and taxonomic biodiversity

There is an increasing emphasis on Protected Areas throughout the world, yet freshwater ecosystems have not been adequately covered by this effort. Most existing FPAs are not designed to protect freshwater biodiversity, and are often protecting historic shipwrecks or are secondary to terrestrial protected areas such as National Parks. Furthermore, hotspots of functional diversity are known to be different from taxonomic diversity hotspots, and yet functional diversity has been rarely considered in the FPA framework.bOverall, there are few guidelines available for nomination and selection of new FPAs, despite the increasing public support for creating additional FPAs and reserves. This Special Session will include primary research, review and opinion contributions relevant to FPAs such as: 1) tools for prioritization of FPAs, outlining areas in more pristine condition, or with highest taxonomic and functional diversity; 2) the role of existing FPAs in conserving freshwater taxonomic and functional diversity; 3) consideration of FPA potential in multi-stressor landscapes; 4) challenges in creating FPAs; 5) the role of FPAs in provisioning ecosystem services.This session, which is clearly relevant to the theme of the meeting - Designing our Freshwater Futures, would continue a conversation about tools needed for protecting remaining intact freshwater areas and maximizing conservation investment in terms of biodiversity and functional diversity.

S14: Stressors in linked aquatic-terrestrial ecosystems: New developments and solutions

Aquatic and terrestrial ecosystems are linked through movements of energy and nutrients which subsidize recipient food webs. As a result, stressors that affect aquatic systems (e.g., nutrients, contaminants, wildfire, and climate change) have the potential to impact both aquatic and terrestrial ecosystem processes. Within the last decade increased attention has been paid to this phenomenon, particularly the effects of aquatic stressors on quantity and quality of resources exported to terrestrial consumers, and the potential implications for management. This session with explore the effects of aquatic stressors on ecological subsidies, predator movement, and food web dynamics at the boundary of aquatic and terrestrial ecosystems. In keeping with the meeting theme "Freshwater solutions", we will explore the tools being developed to help managers and researchers better understand the implications of aquatic stressors on linked aquatic-terrestrial ecosystems and their effects on natural resources and ecosystem processes. By incorporating empirical results, management applications, and theoretical synthesis, this session will provide useful information for academics, government researchers, and consultants. Topics covered in this session include: Ecosystem linkages; Ecological indicators; Tools for monitoring and assessing remedy effectiveness; Multiple stressors; and Restoration, Landscape/network analysis and modelling.

S15: Connectivity and Effects of Carolina and Delmarva Bays, Pocosins, and other Geographically Isolated Wetlands of the Atlantic Coastal Plain

Carolina and Delmarva bays, Pocosins, and other geographically isolated wetlands (GIWs) of the Atlantic Coastal Plain once covered grand swaths of the ecoregion. Today, the extent of most GIWs is substantially less than pre-settlement, and the hydrologic modification of the majority of the remaining wetlands likely affects much of their functioning and integrity. However, recently promulgated – though currently stayed – clarifications to the definition of waters protected by the Clean Water Act (CWA) suggest that CWA protections may be extended to Carolina and Delmarva bays and Pocosins if such waters, individually or cumulatively, substantially affect the chemical, physical, or biological integrity of larger downstream waters such as rivers, lakes, and coastal waters. In this session, we welcome presentations on scientific advances in quantifying the individual and/or cumulative effect of Carolina and Delmarva bays, Pocosins, and other geographically isolated wetlands of the Atlantic Coastal Plain, focusing on the hydrological, biogeochemical, and biological contributions of these important wetland systems.

S16: Understanding and mitigating change in freshwater ecosystem services

Over the last two decades the ecosystem services (ES) approach has developed into an internationally recognized framework for understanding the services that humans derive from nature. In freshwater ecosystems these services range from the tangible, extractable goods such as fish and clean drinking water, to more regulatory services that maintain ecosystem conditions (e.g. nutrient cycling, flood mitigation). However, the benefits that freshwater ES provide are threatened by the effects of human development, pollution, invasive species, agriculture, and climate change, among others. Our symposium will broadly examine the use of the ES approach for monitoring and addressing changes in freshwater ecosystems as a result of anthropogenic disturbances. Applying an ES lens requires a thorough understanding of the links between ecosystem structure and functions with ES. This is a large order as freshwater ecosystems are often one piece of a complex, socio-ecological system with multiple beneficiaries. As a result, ES research can cover many different topics and offer various quantitative and qualitative tools for evaluating the benefits derived from freshwater ecosystems. These techniques can in turn offer insight towards management and policy decisions for mitigating undesirable change and ensuring the provisioning or flow of ES into the future. Presentations will focus on identifying and characterizing the underlying science of freshwater ES experiencing change, methods for quantifying and mapping trends in ES across a variety of regions and scales, and contribute new ideas to how an ES approach can lead to new solutions in the form of changes to management and policy.

S17: Integrating Published Literature into the Science and Policy Arenas Influencing Our Freshwater Futures: Evidence-Based Methods to Fit the Purpose

Evidence-based decision-making is a major goal of scientists working in environmental policy settings, and many researchers cite the need to inform policy as justification for research in grant proposals and publications. Freshwater protection presents unique challenges to policymakers who must evaluate scientific evidence to help assess risks and inform decisions, while also balancing other considerations of stakeholders. The integration of science and policy represents an opportunity to advance solutions that incorporate evidence from published literature into the decision-making process. Freshwater scientists are important in the policy process because they generate and interpret relevant data and information on aquatic systems across multiple scales (spatial, temporal, organismal). Their research can link threats to ecological effects, and freshwater ecology to the goods and services valued by humans. This session aims to highlight a diversity of approaches where published research is evaluated in terms of its utility for policy. This session will showcase specific processes (e.g., systematic review, ecological assessment, causal analysis, strength of evidence frameworks, meta-analytic techniques) that are applied to review and evaluate data and information used in the environmental policy arena. Participants will present recent examples of innovative ways science has been incorporated into decision-making to protect our freshwater futures and demonstrate how the work of researchers can inform water resource policy with fit-for-purpose evidence synthesis. The views expressed in this abstract are those of the authors and do not necessarily represent the views or policies of the US EPA.

S18: Advances in our understanding of the Annelida

Annelids have long been used in biomonitoring studies. These organisms are good bio indicators of pollution and water quality due to close associations with soils and sediments that often accumulate metals and other toxicants. Additionally, these organisms tend to be restricted in their movements making them good indicators of highly localized conditions. However, taxonomic identification of these organisms based on morphology is challenging, complicating our ecological understanding of these taxa and subsequent analyses and corresponding conclusions about the conditions of aquatic systems. This session aims to disseminate information on advances in the taxonomy and ecology of annelids. Studies with a molecular component are especially welcome. We also encourage talks discussing how our advances in understanding of the Annelida can be used in biomonitoring studies.

S19: Elements and energy as fundamental currencies of nature: using ecological stoichiometry as a tool to advance the sustainability of freshwater ecosystems

Freshwater ecosystems are fundamentally influenced by the relative availability of key elements such as nitrogen and phosphorus. They can be sustained, stressed, or altered by the relative availability of and demand for these nutrients. Organisms rarely have access to nutrients and energy in the exact ratio needed to meet the demands of metabolism, somatic growth, and reproduction; thus, these nutrients and energy form fundamental, common currencies in ecological systems. Ecological stoichiometry theory forms a framework to evaluate the dynamics of supply and demand across scales and through time. Freshwater systems are acutely affected by a multitude of stressors which have altered the distribution and abundance of nutrients. Modulating the frequency and magnitude of elemental supply in streams, lakes, and rivers relative to demand is essential for both sustainable ecosystems and management. Successful future management actions will need to incorporate adept forecasting and prediction of freshwater response to variability in supply due to anthropogenic and climatic stressors. Our session will explore how ecological stoichiometry can help to 1) understand the tipping points between supply and demand across scales of ecological organization, 2) synthesize individual studies to inform understanding of how supply and demand influence structure and function within freshwater ecosystems, and 3) elucidate larger patterns across spatial and temporal gradients to inform future freshwater management. The goal of this session is to bring together scientists using ecological stoichiometry across a diversity of organisms, environments, and applications to synthesize our understanding and identify opportunities to improve the sustainability of freshwater ecosystems.

S20: Understanding physical controls on cyanobacteria dominance: toward prediction and prevention

Harmful cyanobacterial blooms (CyanoHABs) are a common feature and increasingly pressing management issue for eutrophic lakes, reservoirs, and streams worldwide. CyanoHABs degrade the quality of potable water supplies, generate hypoxia, shade submerged aquatic vegetation, alter food webs, and reduce the aesthetic value of freshwater systems. While nutrient loading plays an important role in determining total phytoplankton biomass, cyanobacteria dominance may be largely controlled by physical processes. In particular, the strength and frequency of vertical mixing is believed to modulate CyanoHAB potential and possibly toxicity. As such, there is considerable interest and ongoing effort to use enhanced mixing as an in-system treatment option for CyanoHABs. Understanding how physical processes control cyanobacteria dominance and vertical distribution is also critical for CyanoHAB monitoring, forecasting, benthic/pelagic impact assessment, water supply intake protection, and determining how climate change will affect bloom formation potential in the future.

S21: Practical applications of metacommunity theory in stream and river management

Recent research testing metacommunity theory has demonstrated that stream communities are as much a product of dispersal related effects as they are a product of local environmental conditions. Rivers and streams are being impacted by land use change, water use, power generation, waste disposal, invasive species, and climate change. New and innovative management approaches are needed to combat the impacts of these multiple stressors. Given that metacommunity theory enhances our understanding of the role of network structure and connectivity in stream community ecology, it has many potential applications for environmental monitoring, stream restoration, and watershed management and conservation. Many common stream management methods originated when community ecology was more focused on niche or local scale processes and could be enhanced by considering regional processes. For example, biomonitoring science is based on the assumption that local communities are controlled by local conditions; however, communities strongly impacted by dispersal limitation or mass effects may not respond as expected to local scale environmental degradation. Similarly, the expected success of local scale restoration efforts may be strongly influenced by regional scale processes. Additionally, watershed management plans may be enhanced by considerations of connectivity and whole watershed integrity. In this session, we bring together experts on metacommunity ecology and stream and riverine management to highlight recent and current research and synthesis work that draws on our understanding of regional scale processes to further our ability to manage streams and rivers from local to regional scales.

S23: Rehabilitating urban streams: perspectives from science and management

Urban streams provide numerous services highly valued by humans (e.g., nutrient processing, stormwater drainage, drinking water, and recreation), yet land development and direct channel alteration prevent many urban streams from providing these essential ecological and societal benefits. In fact, urban streams are some of the most ecologically impaired aquatic systems on Earth. Existing efforts to rehabilitate urban streams are often limited in scope and spatial extent, largely due to the numerous logistical, financial, ecological, engineering and social challenges associated with improving urban streams. Overcoming these challenges requires creative, interdisciplinary approaches. This special session provides an opportunity to explore these challenges and a range of potential solutions through theoretical framing of issues and case studies. Topics could include: approaches for evaluating locations for focused rehabilitation efforts, defining appropriate and achievable endpoints, barriers to ecological improvement, measuring effectiveness of current methods, and novel approaches for improving urban streams. Presentations from multiple fields of science and management will create space for exploring the current limits of the practice and identifying opportunities for developing innovative, interdisciplinary solutions to these complex problems. Ultimately, this session aims to integrate recent advances in urban stream and watershed management with novel ideas on how to implement more widespread and effective urban stream rehabilitation.

S24: Towards a predictive freshwater ecology: using time-series data to understand and forecast responses to a changing environment

Understanding and predicting changes in freshwater ecosystems through time is a challenging endeavor. Freshwaters often exhibit strong temporal variation in key structural and functional attributes, and it can be difficult to parse stochastic and catastrophic events from seasonal and long-term trends. Pervasive alterations to freshwaters resulting from climate change, land use alterations, and shifts in community composition are superimposed on inherent temporal variability and thus compound this challenge even further. Recently, there has been a growing effort to develop statistical tools that are specifically suited for ecological time series data and provide opportunities to disentangle complex relationships among climate, ecosystem, and catchment variables while improving the quality of predicted responses to future change. This coincides with increased access to both high resolution sensor data and long-term datasets describing the hydrology, chemistry, and ecology of freshwaters. This session will feature contributions that use quantitative methods to analyze time series data (e.g. state space models, wavelet analysis, etc.) to assess variability and response dynamics at various spatial and temporal scales. We welcome contributions that apply statistical modeling approaches to investigate temporal variation in freshwater ecosystems in either basic or applied contexts. Potential topics include but are not limited to temporal dynamics in flow, chemistry, or temperature; community or food-web structure; ecosystem processes; and any combination thereof.

S25: Do mesocosm experiments play a meaningful role in freshwater research

Mesocosms (defined at any size and scale) have been a controversial tool of freshwater sciences, eliciting both criticism and praise for their role in development or testing applied resource issues and ecological theory. Despite greater control and replicability of mesocosm experiments, these are relatively small-scale systems and have significant limitations. In this session, we aim to renew this debate and review the current status of mesocosm science in freshwater research. We encourage scientists to submit talks that use data to support or question the general utility of mesocosm science in designing our freshwater futures. Questions of particular interest could include: Are mesocosms results reproducible and can mesocosm findings be accurately extrapolated to real ecosystem management? Do the benefits of control, random assignment of treatments and replicability in mesocosm experiments outweigh the limited ecological realism and spatiotemporal scale of these systems? How should mesocosms studies be designed to test ecological theory or what are the limits of mesocosm science?

S26: Biological Success Criteria for Stream Restoration Project Monitoring: Are We Still Searching for Unicorns?

Over a decade ago the estimated annual expenditures for stream restoration in the United States reached $1 billion. Although there are numerous incentives for undertaking stream restoration projects, the compensatory mitigation requirements of the federal Clean Water Act, Section 404 (CWA 404) regulatory program provide the incentive for a significant proportion of such projects nationwide. Stream restoration projects can cause significant disturbances to existing physical stream habitats and biological communities as a result of direct channel and floodplain manipulation. These projects are often undertaken with the well intentioned hope that by improving degraded stream habitat, biological stream conditions will also improve. However, there have been comparatively few studies illustrating long-term development trends in the biological communities of restored streams in North America. Despite new federal regulations published in 2008, aimed in part at assuring more objective ecological performance standards (i.e. success criteria) for stream restoration projects undertaken as CWA 404 compensatory mitigation, there remains a significant need for objective biological monitoring metrics capable of predicting long-term biological conditions (improvements) based on monitoring conducted only during the first five to seven years following project implementation. The lack of widely accepted and legitimate biological monitoring metrics has arguably fostered an over reliance on monitoring physical stream features as surrogates for biological conditions in restored streams. This session will focus on research, applied science, biological community development theory and case studies to inform development and/or selection of biological monitoring metrics useful as success criteria for stream restoration projects.

S27: Advancing Consistency in Ecological Assessments

Assessments of ecological condition inform environmental policies and provide a wealth of ecological information for designing our freshwater futures. Consistency in ecological assessments is needed to accurately characterize the results of environmental management, the basis for adaptive management, and tradeoffs in water uses. This session explores the challenges for maintaining consistency in ecological assessments through time, across ecosystem types, among government agencies and across jurisdictional boundaries. The wealth of ecological information provided by national and continental scale ecological assessments has advanced ecological understanding as well as provided a more thorough characterization of the status and trends of human effects on ecological condition. Challenges remain with consistency across ecosystems where natural variability and available knowledge limit use of the same conceptual and analytical methods and ecological parameters. Opportunities for using new field, laboratory, and data analysis methods offer improvements for detail and accuracy of assessments, but they also threaten consistency. Government agencies use different assessment methods even when goals are the same because historical methods used by agencies varied, funding varies, and analytical capabilities may vary. Changing methods of assessment could improve consistency in assessments across ecosystem types and agencies, but threaten consistency through time. This session will address the question, "When should we change methods?" Our goal is to advance consistency in assessments and thereby support management of freshwater futures.

S28: Shared pathways; contributions of citizen science to our freshwater future

Local communities can play a key role in the creation and activation of novel solutions to managing our freshwater ecosystems. As trained citizen scientists, they can greatly increase the collection and analysis of ecological data as well as increasing the impact of the solutions developed. As a more informed public, they support research priorities and sustainable public policy. With the growing opportunities to include citizen scientists, volunteered geographic information and community observatories in regulatory and research based data acquisition, new approaches to integrating novel data gathering and ecological analysis have been developed. Many of these are based on complementary approaches which could reinforce both the scientific results as well as the ongoing engagement of the community participations, yet there are few attempts to share platforms and integrate activities. Best practises and new insights need to be shared to the larger freshwater scientist community. This session will focus on a range of experiences and results from freshwater citizen science projects from across the globe, highlighting novel approaches and new opportunities. Presentations will address key lessons learned, best practices and major challenges in the integration of the contribution of citizen scientists to our freshwater future.

S29: Macrosystem Ecology of Aquatic Systems

An increasingly larger spatial focus in aquatic ecological research is needed to: (a) better understand the functioning of river ecosystems; (b) respond to threats from climate change, species invasions, and increased pressure for more dams and interbasin water transfer; and (c) meet critical needs for catchment-level management. Implementing changes in research and management necessitate new spatiotemporal and research domains and a partial shift from reach-level studies to "macrosystem ecology." Macroecology and associated processes usually cannot be understood simply by scaling up information from smaller extent and finer grain samples because of problems of connectivity and spatial heterogeneity of crucial system components and entanglements from cross-scale interactions producing threshold responses and other nonlinear dynamics. To respond to these needs, NSF's Division of Environmental Biology instituted a research program on biological systems at regional to continental scales termed "Macrosystem Biology." This program is designed to support quantitative, interdisciplinary, systems-oriented research on biosphere processes and their complex interactions with climate, land use, and invasive species at regional to continental scales. Several freshwater macrosystem studies are currently funded by DEB, but the majority of grants have been for terrestrial macrosystems. This 2017 SFS symposium focuses on macrosystem studies of lotic and lentic ecosystems in order to: (i) better inform members on the nature of macrosystem ecology; (ii) describe initial results of ongoing projects; and (iii) encourage development of future projects at this spatial grain and extent. This symposium will include invited presentations and open submissions by conference participants.

S30: The future of trait-based approaches in research and management

Freshwaters offer important services for people around the globe, who in turn pose high demands on these systems. A sustainable use of water and its related resources cannot go without a scientifically underpinned understanding of its functioning. The functioning of a freshwater ecosystem relies on the individual species roles and their mutual interactions in a specific freshwater body. The roles of each individual species are performed based on the combination of traits they possess. The combination of traits that species possess are evolutionary adaptations to the prevailing environmental and biological conditions of their habitat. Furthermore, trait adaptations have phylogenetic constraints, similar to the constraints of the body plan. Species thus 1) do not necessarily use all of their potential traits, 2) traits will not have equal importance for a species in a specific environment and 3) traits will always act in combinations. The combination of functional traits within a species, known as life-history strategies, should provide insight into the environmental conditions to which the species has adapted. How then to use this knowledge on evolution based specialization of trait combinations and application under specific environmental conditions? Which hypothesis and methodologies are available or needed to bring trait-based approach a step further in applied freshwater research and management?

S31: Moving forward in flow ecology: identifying and testing key hypotheses

Freshwater biota are thought to be heavily influenced by changing hydrologic conditions, yet scientists are still struggling to validate many hypothesized responses to flow variability with large empirical datasets. Additionally, flow ecology research has frequently focused on relating hydrology and hydrologic alteration to ecological responses that reflect snapshots of an ecological state (e.g., species richness, biotic index) with limited consideration of dynamic responses (e.g., reproduction, colonization) that represent demographic processes underpinning observed changes in state responses. Progress along both of these fronts would be a boon to freshwater science, as validation of purported flow relationships would facilitate implementation of environmental flow recommendations in data-poor regions. Furthermore, documenting temporally explicit responses to flow variability would provide water resource managers a more mechanistic (rather than correlative) understanding of flow-ecology relationships. This special session aims to move the field of flow ecology forward by offering opportunities to propose critical yet untested flow-related hypotheses, to identify large and diverse datasets that facilitate rigorous tests of these hypotheses, and to highlight novel methods for establishing quantitative relationships between natural hydrology, hydrologic alteration, and ecological responses. Consequently, the session welcomes both conceptual overviews of organism responses to changing flow conditions and empirical flow ecology studies, especially those that focus on temporally dynamic responses.