Environmental Sciences Commons^™

Assessing The Risk Of Carbon Dioxide Emissions From Blue Carbon Ecosystems, Catherine E. Lovelock, Trisha Brooke Atwood, Jeff Baldock, Carlos M. Duarte, Sharyn Hickey, Paul S. Lavery, Pere Masque, Peter I. Macreadie, Aurora M. Ricart, Oscar Serrano, Andy Steven

Watershed Sciences Faculty Publications

“Blue carbon” ecosystems, which include tidal marshes, mangrove forests, and seagrass meadows, have large stocks of organic carbon (C_org) in their soils. These carbon stocks are vulnerable to decomposition and – if degraded – can be released to the atmosphere in the form of CO₂. We present a framework to help assess the relative risk of CO₂ emissions from degraded soils, thereby supporting inclusion of soil C_org into blue carbon projects and establishing a means to prioritize management for their carbon values. Assessing the risk of CO₂ emissions after various kinds of disturbances …

Factoring Attitudes Towards Conflict Risk Into Selection Of Protected Areas For Conservation, Edd Hammill, A. I. Tulloch, H. P. Possingham, N. Strange, K. A. Wilson

Watershed Sciences Faculty Publications

The high incidence of armed conflicts in biodiverse regions poses significant challenges in achieving international conservation targets. Because attitudes towards risk vary, we assessed different strategies for protected area planning that reflected alternative attitudes towards the risk of armed conflicts. We find that ignoring conflict risk will deliver the lowest return on investment. Opting to completely avoid conflict-prone areas offers limited improvements and could lead to species receiving no protection. Accounting for conflict by protecting additional areas to offset the impacts of armed conflicts would not only increase the return on investment (an effect that is enhanced when high-risk areas …

Sediment Supply Versus Local Hydraulic Controls On Sediment Transport And Storage In A River With Large Sediment Loads, David J. Dean, David J. Topping, John C. Schmidt, Ronald E. Griffiths, Thomas A. Sabol

Watershed Sciences Faculty Publications

The Rio Grande in the Big Bend region of Texas, USA, and Chihuahua and Coahuila, Mexico, undergoes rapid geomorphic changes as a result of its large sediment supply and variable hydrology; thus, it is a useful natural laboratory to investigate the relative importance of flow strength and sediment supply in controlling alluvial channel change. We analyzed a suite of sediment transport and geomorphic data to determine the cumulative influence of different flood types on changing channel form. In this study, physically based analyses suggest that channel change in the Rio Grande is controlled by both changes in flow strength and …

Multi-Scale Environmental Filters And Niche Partitioning Govern The Distributions Of Riparian Vegetation Guilds, Nate Hough-Snee, Brian G. Laub, David M. Merritt, Arin Lexine Long, Lloyd L. Nackley, Brett B. Roper, Joseph Michael Wheaton

Watershed Sciences Faculty Publications

Across landscapes, riparian plant communities assemble under varying levels of disturbance, environmental stress, and resource availability, leading to the development of distinct riparian life-history guilds over evolutionary timescales. Identifying the environmental filters that exert selective pressures on specific riparian vegetation guilds is a critical step in setting baseline expectations for how riparian vegetation may respond to environmental conditions anticipated under future global change scenarios. In this study, we ask: (1) What riparian plant guilds exist across the interior Columbia and upper Missouri River basins? (2) What environmental filters shape riparian guild distributions? (3) How does resource partitioning among guilds influence …

Bear Lake Limnology & Nutrient Limnology, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.

Riparian Vegetation, Colorado River, And Climate: Five Decades Of Spatiotemporal Dynamics In The Grand Canyon With River Regulation, Joel B. Sankey, Barbara Ralston, Paul E. Grams, John C. Schmidt, Laura E. Cagney

Watershed Sciences Faculty Publications

Documentation of the interacting effects of river regulation and climate on riparian vegetation has typically been limited to small segments of rivers or focused on individual plant species. We examine spatiotemporal variability in riparian vegetation for the Colorado River in Grand Canyon relative to river regulation and climate, over the five decades since completion of the upstream Glen Canyon Dam in 1963. Long-term changes along this highly modified, large segment of the river provide insights for management of similar riparian ecosystems around the world. We analyze vegetation extent based on maps and imagery from eight dates between 1965 and 2009, …

Population Trend Of The World’S Monitored Seabirds, 1950-2010, Michelle Paleczny, Edd Hammill, Vasiliki Karpouzi, Daniel Pauly

Watershed Sciences Faculty Publications

Seabird population changes are good indicators of long-term and large-scale change in marine ecosystems, and important because of their many impacts on marine ecosystems. We assessed the population trend of the world’s monitored seabirds (1950–2010) by compiling a global database of seabird population size records and applying multivariate autoregressive state-space (MARSS) modeling to estimate the overall population trend of the portion of the population with sufficient data (i.e., at least five records). This monitored population represented approximately 19% of the global seabird population. We found the monitored portion of the global seabird population to have declined overall by 69.7% between …

Water Quantity And Quality In The Columbia Basin Trust Region, Janice Brahney

Watershed Sciences Faculty Publications

This report collects the documents generated as part of a two year effort to catalogue the variety of water quality and quantity data that has been collected in the Columbia Basin Trust region of British Columbia. Through the cataloguing effort, a number of important data and knowledge gaps were identified and specific recommendations developed. The available water quantity and climate data was then used in a number of analyses focused on understanding the relationship between changing climate conditions and stream discharges.

One overall finding is that there is a large variety of data collected and held by various different entities. …

Can The Causeway In The Great Salt Lake Be Used To Manage Salinity, Sarah E. Null, Wayne A. Wurtsbaugh, Craig Miller

Watershed Sciences Faculty Publications

No abstract provided.

A Study Of The Spawning Ecology And Early Life History Survival Of Bonneville Cutthroat Trout, Phaedra E. Budy, Sarah Wood, Brett B. Roper

Watershed Sciences Faculty Publications

We completed a large-scale field experiment in four tributaries of the Logan River, Utah, where the largest metapopulation of imperiled Bonneville cutthroat trout Oncorhynchus clarkii utah persists. We documented the spatial and temporal distributions of spawners, quantified substrate use versus substrate availability, and evaluated differences in hatch and emergence fry success between and among sites in relation to habitat characteristics. We observed considerable variability in the timing, magnitude, and duration of spawning among study areas (streams), in part as a function of a variable, multipeaked hydrograph. Nevertheless, across study areas, >70% of redds were constructed on the final descending limb …

Nitrogen Partitioning And Transport Through A Subalpine Lake Measured With An Isotope Tracer, Dave M. Epstein, Wayne A. Wurtsbaugh, Michelle A. Baker

Watershed Sciences Faculty Publications

We used a stable isotope tracer to measure nitrogen (N) assimilation and transfer through Bull Trout Lake, a 0.3-km2 mountain lake in Idaho, specifically to explore the relative importance of pelagic and benthic producers. was added into the inflow stream above the lake during spring runoff and the resulting mass of tracer was measured within the various ecosystem compartments, including the outflow stream. Although a portion of the moved through the lake quickly due to a low hydraulic residence time during the addition, the tracer was also assimilated rapidly by seston in the water column and at a slower rate …

Automatic Geomorphic Feature Extraction From Lidar In Flat And Engineered Landscapes, Paola Passalacqua, Patrick Belmont, Efi Foufoula-Georgiou

Watershed Sciences Faculty Publications

High-resolution topographic data derived from light detection and ranging (lidar) technology enables detailed geomorphic observations to be made on spatially extensive areas in a way that was previously not possible. Availability of this data provides new opportunities to study the spatial organization of landscapes and channel network features, increase the accuracy of environmental transport models, and inform decisions for targeting conservation practices. However, with the opportunity of increased resolution topographic data come formidable challenges in terms of automatic geomorphic feature extraction, analysis, and interpretation. Low-relief landscapes are particularly challenging because topographic gradients are low, and in many places both the …

Mercury In The Pelagic And Benthic Food Webs Of The Great Salt Lake, Wayne A. Wurtsbaugh, Erin Fleming, Caleb Izdepski, Jodi Gardberg

Watershed Sciences Faculty Publications

No abstract provided.

Large Shift In Source Of Fine Sediment In The Upper Mississippi River, Patrick Belmont, Karen B. Gran, Shawn P. Schottler, Peter Wilcock, Stephanie S. Day, Carrie Jennings, J. Wesley Lauer, Enrica Viparelli, Jane K. Willenbring, Daniel R. Engstrom, Gary Parker

Watershed Sciences Faculty Publications

Although sediment is a natural constituent of rivers, excess loading to rivers and streams is a leading cause of impairment and biodiversity loss. Remedial actions require identification of the sources and mechanisms of sediment supply. This task is complicated by the scale and complexity of large watersheds as well as changes in climate and land use that alter the drivers of sediment supply. Previous studies in Lake Pepin, a natural lake on the Mississippi River, indicate that sediment supply to the lake has increased 10-fold over the past 150 years.Herein we combine geochemical fingerprinting and a suite of geomorphic change …

Mercury And Selenium Bioaccumulation In The Stromatolite Community Of The Great Salt Lake, Utah, Usa, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.

Closing The Gap Between Watershed Modeling, Sediment Budgeting, And Stream Restoration, Sean M.C. Smith, Patrick Belmont, Peter Wilcock

Watershed Sciences Faculty Publications

The connection between stream restoration and sediment budgeting runs both ways: stream restoration is proposed as a means to reduce sediment yields, but an accurate understanding of sediment supply is necessary to design an effective project. Recent advances in monitoring technology, geochemical techniques, high-resolution topography data, and numerical modeling provide new opportunities to estimate sediment erosion, transport, and deposition rates; upscale them in a geomorphically relevant fashion; and synthesize sediment dynamics at watershed scales. For practical application at large scale, watershed models used to predict yield often do not resolve lower-order channels, leaving an essential “blind spot” regarding sediment processes. …

Revisiting Scaling Laws In River Basins: New Considerations Across Hillslope And Fluvial Regimes, Chandana Gangodagamage, Patrick Belmont, Efi Foufoula-Georgiou

Watershed Sciences Faculty Publications

Increasing availability of high‐resolution (1 m) topography data and enhanced computational processing power present new opportunities to study landscape organization at a detail not possible before. Here we propose the use of “directed distance from the divide” as the scale parameter (instead of Horton’s stream order or upstream contributing area) for performing detailed probabilistic analysis of landscapes over a broad range of scales. This scale parameter offers several advantages for applications in hydrology, geomorphology, and ecology in that it can be directly related to length‐scale dependent processes, it can be applied seamlessly across the hillslope and fluvial regimes, and it …

Lakes As Buffers Of Stream Dissolved Organic Matter (Dom) Variability: Temporal Patterns Of Dom Characteristics In Mountain Stream-Lake Systems, K. J. Goodman, Michelle A. Baker, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Lakes within fluvial networks may affect dissolved organic matter (DOM) dynamics in streams by dampening spring DOM snowmelt flushing responses and/or by increasing summer DOM production. We assessed the temporal variability of dissolved organic carbon (DOC) concentration and DOM characteristics (specific ultraviolet absorbance (SUVA254); DOC:dissolved organic nitrogen (DOC:DON)), as well as DOC export in seven paired lake inflows and outflows in the Sawtooth Mountain lake district, Idaho. We hypothesized that lakes would decrease stream DOM temporal variability and increase DOM export as a result of autotrophic production. We correlated DOM variability with landscape factors to evaluate potential drivers of DOM …

Predator Functional Response Changed By Induced Defenses In Prey, Edd Hammill, Owen L. Petchey, Bradley R. Anholt

Watershed Sciences Faculty Publications

Functional responses play a central role in the nature and stability of predator‐prey population dynamics. Here we investigate how induced defenses affect predator functional responses. In experimental communities, prey (Paramecium) expressed two previously undocumented inducible defenses—a speed reduction and a width increase—in response to nonlethal exposure to predatory Stenostomum. Nonlethal exposure also changed the shape of the predator’s functional response from Type II to Type III, consistent with changes in the density dependence of attack rates. Handling times were also affected by prey defenses, increasing at least sixfold. These changes show that induced changes in prey have a real defensive …

Absence Of Predation Eliminates Coexistence: Experience From The Fish-Zooplankton Interface, Z. M. Gilwicz, Wayne A. Wurtsbaugh, E. Szymansk

Watershed Sciences Faculty Publications

Examples from fishless aquatic habitats show that competition among zooplankton for resources instigates rapid exclusion of competitively inferior species in the absence of fish predation, and leads to resource monopolization by the superior competitor. This may be a single species or a few clones with large body size: a cladoceran such as Daphnia pulicaria, or a branchiopod such as Artemia franciscana, each building its population to a density far higher than those found in habitats with fish. The example of zooplankton from two different fish-free habitats demonstrates the overpowering force of fish predation by highlighting the consequences of its absence. …

Landscape Limnology: Nutrient Fluxes & Biotic Stability In Complex Mountain Watersheds, Wayne A. Wurtsbaugh, Michelle Kang, Dave M. Epstein

Watershed Sciences Faculty Publications

No abstract provided.

Nutrient Limitation Of Phytoplankton By Nitrogen And Phosphorus: Erosion Of The Phosphorus Paradigm, Wayne A. Wurtsbaugh, William M. Lewis Iii

Watershed Sciences Faculty Publications

No abstract provided.

Mercury In The Biostrome Community Of The Great Salt Lake, Wayne A. Wurtsbaugh, Caleb Izdepski

Watershed Sciences Faculty Publications

No abstract provided.

Freshwater Responses To Nitrogen And Phosphorus Pollution And A Case Study Of Cutler And Dingle Marsh Wetlands, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.

Extreme Eutrophication And Cyanotoxin Levels In Farmington Bay, A Polluted Embayment Of The Great Salt Lake, Utah, Wayne A. Wurtsbaugh, Amy M. Marcarelli, Gregory Boyer

Watershed Sciences Faculty Publications

The Great Salt Lake of Utah is surrounded on its eastern and southern shores by 1.4 million people, with projections of 5 million by 2050. Agricultural, industrial and particularly secondary-treated domestic wastes from this population flow primarily into Farmington Bay, a 280 km2 shallow "estuary" with a mean depth near 0.5 m. Fish are rare but bird use is extensive and massive mortalities of waterfowl and shorebirds have occurred in the bay. Phosphorus loading rates of >2 g m-2yr-1 cause hypereutrophic conditions: Secchi depths are usually 0.6 mg/L, mean Chl. a is 179 ug/L and the combined trophic state index …

Evaluating The Effectiveness Of Grassbed Treatments As Habitat For Juvenile Black Bass In A Drawdown Reservoir, D. R. Ratcliff, Wayne A. Wurtsbaugh, J. Zustak

Watershed Sciences Faculty Publications

Many reservoirs in arid regions experience highly variable water levels caused by seasonal inflow fluctuations and designated outflow requirements. At Shasta Lake, California, managers plant cereal-grain grassbeds on exposed drawdown shorelines to increase juvenile fish habitat, localize productivity, and increase invertebrate fish prey. To determine the efficacy of these plantings, the abundance of juvenile black basses Micropterus spp. (20–55 mm standard length) and the amount of periphyton and macroinvertebrate prey were compared among three treatment types: (1) planted grassbeds of cereal barley Hordeum vulgare; (2) artificial rope grassbeds, which eliminated physical deterioration and nutrient release; and (3) nonplanted control sites …

Limnological Analyses Of Cutler Reservoir And Dingle Marsh With Respect To Eutrophication, J. D. Abbott, Deb Collins, Colin Cook, Dan Lamarra, Ryan Leonard, Ben Marret, Justin Stout, Gilbert Rowley, Jeremy Rowley, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Cutler Reservoir is located in Cache county, Utah and was created for the purposes of irrigation, water storage and flood control. High nutrient loading to Cutler has raised concerns about the health of this system and has resulted in it being listed on the state's 303(d) list of impaired waters. The TMDL plan being drafted for Cutler lists dissolved oxygen and phosphorous as the key issues of concern. The underlying problem created by nutrient loading is eutrophication. If Cutler is to remain as a valuable source of recreation, wildlife habitat, and water for the Cache Valley we must understand the …

Nutrient Loading And Eutrophication In The Great Salt Lake, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.

Timing And Cause Of Water Level Fluctuations In Kluane Lake, Yukon Territory, Over The Past 5000 Years, Janice Brahney, John J. Clague, Brian Menounos, Thomas W. D. Edwards

Watershed Sciences Faculty Publications

We reconstructed late Holocene fluctuations of Kluane Lake in Yukon Territory from variations in bulk physical properties and carbon and nitrogen elemental and isotopic abundances in nine sediment cores. Fluctuations of Kluane Lake in the past were controlled by changes in climate and glaciers, which affected inflow of Slims and Duke rivers, the two largest sources of water flowing into the lake. Kluane Lake fluctuated within a narrow range, at levels about 25 m below the present datum, from about 5000 to 1300 cal yr BP. Low lake levels during this interval are probably due to southerly drainage of Kluane …

Lakes And Forests As Determinants Of Downstream Nutrient Concentrations In Small Mountain Watersheds, P. D. Brown, Wayne A. Wurtsbaugh, K. Nydick

Watershed Sciences Faculty Publications

Lakes are dynamic processors of nutrients and may hold an active role in modifying the water chemistry of stream systems. In this study, we examine the influence of lakes and an important terrestrial component—forest cover—on the nutrient levels of stream water in 11 Rocky Mountain (Idaho) watersheds. Water samples were collected from the inflow and outflow of lakes with varying amounts of upstream lakes and forested area during spring runoff and summer base flow. During base flow, mean total nitrogen concentrations at the inflow of final lakes were significantly related to relative upstream lake area, increasing from 34 to 103 …