Physical Sciences and Mathematics Commons^™

The Impacts Of Anthropogenic Activity And Climate Change On The Formation Of Harmful Algal Blooms (Habs) And Its Ecological Consequence, Zhangxi Hu, Aifeng Li, Zhun Li, Margaret R. Mulholland

OES Faculty Publications

No abstract provided.

Impact Of Streambank Stabilization On Sediment Deposition And Erosion In Central Nebraska Streams, Matthew Russell

School of Natural Resources: Dissertations, Theses, and Student Research

Stabilization projects are increasingly used to mitigate the effects of anthropogenic streambank erosion, yet the effectiveness of these practices has been insufficiently monitored and assessed to date. Sound monitoring practices promote engineered effectiveness, in addition to allowing adjustments in implementation and maintenance to improve practices over time. However, current methods to quickly and efficiently quantify deposition and erosion within a stream continue to be costly and inefficient. Therefore, the objectives of this project were to 1) Measure streambank migration of three reaches at Cedar River in Nebraska, from 1993 to 2006 (pre-stabilization) and from 2006 to 2018 (post-stabilization) using aerial …

Engineered Nanoparticles Interact With Nutrients To Intensify Eutrophication In A Wetland Ecosystem Experiment, Marie Simonin, Benjamin P. Colman, Steven M. Anderson, Ryan S. King, Matthew T. Ruis, Astrid Avellan, Christina M. Bergemann, Brittany G. Perrotta, Nicholas K. Geitner, Mengchi Ho, Belen De La Barrera, Jason M. Unrine, Gregory V. Lowry, Curtis J. Richardson, Mark R. Wiesner, Emily S. Bernhardt

Plant and Soil Sciences Faculty Publications

Despite the rapid rise in diversity and quantities of engineered nanomaterials produced, the impacts of these emerging contaminants on the structure and function of ecosystems have received little attention from ecologists. Moreover, little is known about how manufactured nanomaterials may interact with nutrient pollution in altering ecosystem productivity, despite the recognition that eutrophication is the primary water quality issue in freshwater ecosystems worldwide. In this study, we asked two main questions: (1) To what extent do manufactured nanoparticles affect the biomass and productivity of primary producers in wetland ecosystems? (2) How are these impacts mediated by nutrient pollution? To address …

Environmental Proteomics Reveals Taxonomic And Functional Changes In An Enriched Aquatic Ecosystem, Amanda C. Northrop, Rachel K. Brooks, Aaron M. Ellison, Nicholas J. Gotelli, Bryan A. Ballif

College of Arts and Sciences Faculty Publications

Aquatic ecosystem enrichment can lead to distinct and irreversible changes to undesirable states. Understanding changes in active microbial community function and composition following organic matter loading in enriched ecosystems can help identify biomarkers of such state changes. In a field experiment, we enriched replicate aquatic ecosystems in the pitchers of the northern pitcher plant, Sarracenia purpurea. Shotgun metaproteomics using a custom metagenomic database identified proteins, molecular pathways, and contributing microbial taxa that differentiated control ecosystems from those that were enriched. The number of microbial taxa contributing to protein expression was comparable between treatments; however, taxonomic evenness was higher in controls. …

Presence Of The Cyanotoxin Microcystin In Arctic Lakes Of Southwestern Greenland, Jessica Trout-Haney, Zachary Wood, Kathryn Cottingham

Dartmouth Scholarship

Cyanobacteria and their toxins have received significant attention in eutrophic temperate and tropical systems where conspicuous blooms of certain planktonic taxa release toxins into fresh water, threatening its potability and safe use for recreation. Although toxigenic cyanobacteria are not confined to high nutrient environments, bloom-forming species, or planktonic taxa, these other situations are studied les often studied. For example, toxin production in picoplankton and benthic cyanobacteria—the predominant photoautotrophs found in polar lakes—is poorly understood. We quantified the occurrence of microcystin (MC, a hepatotoxic cyanotoxin) across 18 Arctic lakes in southwestern Greenland. All of the focal lakes contained detectable levels of …

Slides: Water Planning In California: Past, Present, Future, Ellen Hanak

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Presenter: Ellen Hanak, Senior Fellow and Director, PPIC Water Policy Center, Public Policy Institute of California

13 slides

Collaborative Research: Interactive Effects Of Chronic N Deposition, Acidification, And Phosphorus Limitation On Coupled Element Cycling In Streams, Kevin S. Simon, Ivan J. Fernandez, Stephen Norton

University of Maine Office of Research Administration: Grant Reports

Human activity has doubled the amount of nitrogen on the landscape, creating a pollution problem and changing the balance among multiple nutrients that limit biological activity in ecosystems. At the same time, other disturbances, such as acidification, interact with nitrogen enrichment in ways that strongly influence the productivity and health of terrestrial and aquatic ecosystems. This project examines the interactions among multiple elements and disturbances (nitrogen, phosphorus, metals, and acidification) along a continuum from the atmosphere through soils to streams. This project takes advantage of two unique experiments in which entire watersheds have been experimentally enriched with nitrogen and acid …

Evaluation Of Trophic Niche Overlap Between Native Fishes And Young-Of-The-Year Common Carp, Michael J. Weber, Jessica M. Howell, Michael L. Rown

Michael J Weber Dr

Common carp Cyprinus carpio is a ubiquitous invasive species that commonly imposes negative effects on aquatic ecosystems. However, research evaluating the effects of carp on native fishes is limited. Carp are highly fecund and larvae and juveniles can be abundant. If age-0 carp use similar prey resources as native fishes, they may compete if food becomes limited. We used traditional diet analysis for samples during Jul. and Aug. 2008 in Brant Lake. Stable sotopes were used for samples collected during Aug. and Sep. 2009 in Brant Lake and Lake Sinai to examine prey resource use by age-0 carp and four …

Method Analysis Of Laboratory Measures Of Stream Sediment And Water Phosphorus Equilibrium, Anna L. Erickson, Stephanie M. Williamson, Brian E. Haggard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Elevated phosphorus concentrations in aquatic ecosystems of northwest Arkansas prompted an investigation of the effects of sample preparation and extraction methods on laboratory measures of sediment-phosphorus interactions. Two streams of contrasting phosphorus (P) concentrations were selected to determine the effect of using a CaCl2 solution instead of filtered stream water, refrigerated or dried sediments instead of fresh wet sediments, and vortexing the suspensions instead of shaking them. Sediment equilibrium P concentration (EPC0) and P buffering capacity (K) were used to determine differences in extraction methods. EPC0 and K from extractions using fresh sediments and a CaCl2 solution matching the electrical …

Water Management In The Binational Texas/Mexico Rio Grande/Rio Bravo Basin [Abstract], Mary E. Kelly

Allocating and Managing Water for a Sustainable Future: Lessons from Around the World (Summer Conference, June 11-14)

2 pages.

Transboundary Watersheds: Changing Environments And Streams Of Thought [Abstract], Roger S. Pulwarty, Robert Varady, Leah Stauber

Allocating and Managing Water for a Sustainable Future: Lessons from Around the World (Summer Conference, June 11-14)

2 pages.

Allocating Tradeable Rights In Water: Lessons From Australia’S Recent Experience In Water Law Reform [Abstract], Poh-Ling Tan

Allocating and Managing Water for a Sustainable Future: Lessons from Around the World (Summer Conference, June 11-14)

1 page.

Primary Productivity, Water Quality, And Limiting Factors In Lake Chicot, Edmond J. Bacon

Technical Reports

Primary productivity, water quality, and limiting factors of productivity were studied in Lake Chicot from 1 July 1975 to 30 September 1977 to ascertain the ameliorating effects of a comprehensive water quality improvement project. The upper lake receives only limited local run-off, but run-off from 350 square miles of agricultural land enters the lower lake through Connerly Bayou, the principal polluted tributary. Run-off over the predominantly silt and clay soils in the subsidized agricultural area contributes excessive amounts of colloidal silt and clay to the lower lake. Connerly Bayou also contributes additional amounts of nutrients including calcium, magnesium, potassium, sodium, …

Pre- And Post Impoundment Ichthyoparasite Succession In A New Arkansas Reservoir, David A. Becker, William D. Carr, Robert G. Heard, Donald G. Cloutman, Perry D. Holmes, Wallace A. Evans, Mitchell D. Norman, Wilbur B. Owen Jr.

Technical Reports

Helminth and crustacean parasites from 2,387 Micropterus dolomieui, M. punctulatus, and M. salmoides were utilized to monitor annual pre- and postimpoundment succession patterns spanning eight con- tinuous years in Beaver Reservoir, Arkansas. Incidence of infection by ichthyoparasites with direct life cycles (monogenetic trematodes, leeches, and crustaceans) generally increased following impoundment, although leeches remained relatively constant. Exceptions to this general pattern occurred. Incidence of ichthyoparasites with indirect life cycles (digenetic trematodes, cestodes, acanthocephalans, and nematodes) decreased immediately following impoundment with subsequent increases to a point equal or above that of preimpoundment, although exceptions occurred. Time for species adaptation to the reservoir …