Physical Sciences and Mathematics Commons^™

Climate Change-Driven Cumulative Mountain Pine Beetle-Caused Whitebark Pine Mortality In The Greater Yellowstone Ecosystem, William W. Macfarlane, Brian Howell, Jesse A. Logan, Ally L. Smith, Cashe C. Rasmussen, Robert E. Spangler

Watershed Sciences Faculty Publications

An aerial survey method called the Landscape Assessment System (LAS) was used to assess mountain pine beetle (Dendroctonus ponderosae)-caused mortality of whitebark pine (Pinus albicaulis) across the Greater Yellowstone Ecosystem (59,000 km²; GYE). This consisted of 11,942 km of flightlines, along which 4434 geo-tagged, oblique aerial photos were captured and processed. A mortality rating of none to severe (0–4.0 recent attack or 5.0–5.4 old attack) was assigned to each photo based on the amount of red (recent attack) and gray (old attack) trees visible. The method produced a photo inventory of 74 percent of …

The Irrigation Efficiency Trap: Rational Farm-Scale Decisions Can Lead To Poor Hydrologic Outcomes At The Basin Scale, Christina N. Morrisett, Robert W. Van Kirk, London O. Bernier, Andrea L. Holt, Chloe B. Perel, Sarah E. Null

Watershed Sciences Faculty Publications

Agricultural irrigation practices have changed through time as technology has enabled more efficient conveyance and application. In some agricultural regions, irrigation can contribute to incidental aquifer recharge important for groundwater return flows to streams. The Henrys Fork Snake River, Idaho (United States) overlies a portion of the Eastern Snake Plain Aquifer, where irrigated agriculture has occurred for over a century. Using irrigator interviews, aerial and satellite imagery, and statistical streamflow analysis, we document the impact of farm-scale decisions on basin-scale hydrology. Motivated to improve economic efficiency, irrigators began converting from surface to center-pivot sprinkler irrigation in the 1950s, with rapid …

Storing Water For The Environment: Operating Reservoirs To Improve California’S Freshwater Ecosystems, Sarah Null, Jeffrey Mount, Brian Gray, Kristen Dybala, Gokce Sencan, Anna Sturrock, Barton Thompson, Harrison Zeff

Watershed Sciences Faculty Publications

California’s freshwater ecosystems—its lakes, rivers, floodplains, meadows, natural and managed wetlands, and estuaries—are a vital part of the state’s natural infrastructure. These ecosystems provide numerous benefits, including water supply, hydropower, flood control, fisheries, recreation, and cultural and aesthetic value. They are also home to the nation’s most diverse array of plant and animal communities, with numerous freshwater species found only in California (Jensen et al. 1993; Grantham et al. 2017).

Managing Water Stored For The Environment During Drought, Sarah Null, Jeffrey Mount, Brian Gray, Michael Dettinger, Kristen Dybala, Gokce Sencan, Anna Sturrock, Barton Thompson, Harrison Zeff

Watershed Sciences Faculty Publications

Storing water in reservoirs is important for maintaining freshwater ecosystem health and protecting native species. Stored water also is essential for adapting to the changing climate, especially warming and drought intensification. Yet, reservoir operators often treat environmental objectives as a constraint, rather than as a priority akin to water deliveries for cities and farms. Reservoir management becomes especially challenging during severe droughts when surface water supplies are scarce, and urban and agricultural demands conflict with water supplies needed to maintain healthy waterways and wetlands. In times of drought, most freshwater ecosystems suffer.

This blog post examines 2021 water year actions …

Spatial And Long-Term Temporal Changes In Water Quality Dynamics Of The Tonle Sap Ecosystem, Savoeurn Soum, Peng Bun Ngor, Thomas E. Dilts, Sapana Lohani, Suzanne Kelson, Sarah E. Null, Flavia Tramboni, Zeb S. Hogan, Bunyeth Chan, Sudeep Chandra

Watershed Sciences Faculty Publications

Tonle Sap lake-river floodplain ecosystem (TSE) is one of the world’s most productive freshwater systems. Changes in hydrology, climate, population density, and land use influence water quality in this system. We investigated long term water quality dynamics (22 years) in space and time and identified potential changes in nutrient limitation based on nutrient ratios of inorganic nitrogen and phosphorus. Water quality was assessed at five sites highlighting the dynamics in wet and dry seasons. Predictors of water quality included watershed land use, climate, population, and water level. Most water quality parameters varied across TSE, except pH and nitrate that remained …

Evaluating The Relationship Between Meander-Bend Curvature, Sediment Supply, And Migration Rates, Mitchell Donovan, Patrick Belmont, Zoltán Sylvester

Watershed Sciences Faculty Publications

River meander migration plays a key role in the unsteady “conveyor belt” of sediment redistribution from source to sink areas. The ubiquity of river meandering is evident from remotely sensed imagery, which has allowed for long-term, high-resolution studies of river channel change and form-process relationships. Empirical, experimental, and theoretical research approaches have described two distinct relationships between channel curvature and river channel migration rates. In this study, we employ a novel application of time-series algorithms to calculate migration rates and channel curvature at sub-meander bend length scales using 6 decades of aerial imagery spanning 205 km of the Minnesota River …

Impacts Of Climate Change On Multiple Use Management Of Bureau Of Land Management Land In The Intermountain West, Usa, Elaine M. Brice, Brett A. Miller, Hongchao Zhang, Kirsten Goldstein, Scott N. Zimmer, Guenchik J. Grosklos, Patrick Belmont, Courtney G. Flint, Jennifer E. Givens, Peter B. Adler, Mark W. Brunson, Jordan W. Smith

Watershed Sciences Faculty Publications

Although natural resource managers are concerned about climate change, many are unable to adequately incorporate climate change science into their adaptation strategies or management plans, and are not always aware of or do not employ the most current scientific knowledge. One of the most prominent natural resource management agencies in the United States is the Bureau of Land Management (BLM), which is tasked with managing over 248 million acres (>1 million km²) of public lands for multiple, often conflicting, uses. Climate change will affect the sustainability of many of these land uses and could further increase conflicts …

Plastic Rain In Protected Areas Of The United States, Janice Brahney, Margaret Hallerud, Eric Heim, Maura Hahnenberger, Suja Sukumaran

Watershed Sciences Faculty Publications

Eleven billion metric tons of plastic are projected to accumulate in the environment by 2025. Because plastics are persistent, they fragment into pieces that are susceptible to wind entrainment. Using high-resolution spatial and temporal data, we tested whether plastics deposited in wet versus dry conditions have distinct atmospheric life histories. Further, we report on the rates and sources of deposition to remote U.S. conservation areas. We show that urban centers and resuspension from soils or water are principal sources for wet-deposited plastics. By contrast, plastics deposited under dry conditions were smaller in size, and the rates of deposition were related …

Modelling Eurasian Beaver Foraging Habitat And Dam Suitability, For Predicting The Location And Number Of Dams Throughout Catchments In Great Britain, Hugh A. Graham, Alan Puttock, William W. Macfarlane, Joseph Michael Wheaton, Jordan T. Gilbert, Róisín Campbell-Palmer, Mark Elliott, Martin J. Gaywood, Karen Anderson, Richard E. Brazier

Watershed Sciences Faculty Publications

Eurasian beaver (Castor fiber) populations are expanding across Europe. Depending on location, beaver dams bring multiple benefits and/or require management. Using nationally available data, we developed: a Beaver Forage Index (BFI), identifying beaver foraging habitat, and a Beaver Dam Capacity (BDC) model, classifying suitability of river reaches for dam construction, to estimate location and number of dams at catchment scales. Models were executed across three catchments, in Great Britain (GB), containing beaver. An area of 6747 km² was analysed for BFI and 16,739 km of stream for BDC. Field surveys identified 258 km of channel containing beaver …

A New Sampler For The Collection And Retrieval Of Dry Dust Deposition, Janice Brahney, Gregory Wetherbee, Graham A. Sexstone, C. Youngbull, P. Strong, Ruth C. Heindel

Watershed Sciences Faculty Publications

Atmospheric dust can influence biogeochemical cycles, accelerate snowmelt, and affect air, water quality, and human health. Yet, the bulk of atmospherically transported material remains poorly quantified in terms of total mass fluxes and composition. This lack of information stems in part from the challenges associated with measuring dust deposition. Here we report on the design and efficacy of a new dry deposition sampler (Dry Deposition Sampling Unit (DSU)) and method that quantifies the gravitational flux of dust particles. The sampler can be used alone or within existing networks such as those employed by the National Atmospheric Deposition Program (NADP). Because …

Potential For Managed Aquifer Recharge To Enhance Fish Habitat In A Regulated River, Robert W. Van Kirk, Bryce A. Contor, Christina N. Morrisett, Sarah E. Null, Ashly S. Loibman

Watershed Sciences Faculty Publications

Managed aquifer recharge (MAR) is typically used to enhance the agricultural water supply but may also be promising to maintain summer streamflows and temperatures for cold-water fish. An existing aquifer model, water temperature data, and analysis of water administration were used to assess potential benefits of MAR to cold-water fisheries in Idaho’s Snake River. This highly-regulated river supports irrigated agriculture worth US $10 billion and recreational trout fisheries worth $100 million. The assessment focused on the Henry’s Fork Snake River, which receives groundwater from recharge incidental to irrigation and from MAR operations 8 km from the river, addressing (1) the …

Glaciers In The Canadian Columbia Basin, Technical Report, Brian Menounos, Ben M. Pelto, Sean W. Fleming, R. Dan Moore, Frank Weber, Dave Hutchinson, Janice Brahney

Watershed Sciences Faculty Publications

The cryosphere - all forms of frozen water on Earth- plays a fundamental role in its climate system. Seasonal snow, mountain glaciers, ice sheets, and sea ice reflect much of the incoming shortwave radiation at high latitudes and in mountainous terrain back to space, helping to regulate the surface temperature of the planet. Accelerating concentrations of greenhouse gases (Solomon et al. 2009) are responsible for late twentieth and early twenty-first century tropospheric warming; this warming in turn drives large-scale changes in the cryosphere, with global implications that include changes in hemispheric circulation (Francis and Vavrus 2012), sea level rise (Gardner …

Consequences Of Didymo Blooms In The Transnational Kootenay River Basin, Niall G. Clancy, Janice Brahney, Jeff Curtis, Phaedra E. Budy

Watershed Sciences Faculty Publications

Stream habitat changes that affect primary consumers often indirectly impact secondary consumers such as fishes. Blooms of the benthic algae Didymosphenia geminata (Didymo) represent one such habitat change known to affect stream macroinvertebrates. However, the potential indirect trophic impacts on fish consumers via modifications to their diet are poorly understood. The overall goal of this project was to determine if Didymo blooms in streams of the Kootenay River basin of British Columbia and Montana affect the condition and growth of fishes, and to see whether trophic mechanisms were responsible for any observed changes. We therefore quantified the diet, condition, and …

Evidence For Accelerated Weathering And Sulfate Export In High Alpine Environments, John T. Crawford, Eve-Lyn S. Hinckley, M. Iggy Litaor, Janice Brahney, Jason C. Neff

Watershed Sciences Faculty Publications

High elevation alpine ecosystems—the 'water towers of the world'—provide water for human populations around the globe. Active geomorphic features such as glaciers and permafrost leave alpine ecosystems susceptible to changes in climate which could also lead to changing biogeochemistry and water quality. Here, we synthesize recent changes in high-elevation stream chemistry from multiple sites that demonstrate a consistent and widespread pattern of increasing sulfate and base cation concentrations or fluxes. This trend has occurred over the past 30 years and is consistent across multiple sites in the Rocky Mountains of the United States, western Canada, the European Alps, the Icelandic …

Resurgence Of An Apex Marine Predator And The Decline In Prey Body Size, Jan Ohlberger, Daniel E. Schindler, Eric J. Ward, Timothy E. Walsworth, Timothy E. Essington

Watershed Sciences Faculty Publications

In light of recent recoveries of marine mammal populations worldwide and heightened concern about their impacts on marine food webs and global fisheries, it has become increasingly important to understand the potential impacts of large marine mammal predators on prey populations and their life-history traits. In coastal waters of the northeast Pacific Ocean, marine mammals have increased in abundance over the past 40 to 50 y, including fish-eating killer whales that feed primarily on Chinook salmon. Chinook salmon, a species of high cultural and economic value, have exhibited marked declines in average size and age throughout most of their North …

Beavers Alter Stream Macroinvertebrate Communities In Northeastern Utah, Susan E. Washko, Brett B. Roper, Trisha Brooke Atwood

Watershed Sciences Faculty Publications

1. Understanding changes in macroinvertebrate communities is important because they play a large role in stream ecosystem functioning, and they are an important food resource for fish. Beaver‐induced changes to stream morphology could alter macroinvertebrate communities, which in turn could affect food webs and ecosystem function. However, studies investigating the effects of North American beaver activities on macroinvertebrates are rare in the inter‐mountain west, an area with high potential for beaver‐assisted restoration.
2. The aim of this study was to quantify differences in the macroinvertebrate community between unaltered segments of streams and within beaver ponds in north‐eastern Utah, U.S.A. We assessed macroinvertebrate …

Evidence For Large Holocene Earthquakes Along The Denali Fault In Southwest Yukon, Canada, Andrée Blais-Stevens, John J. Clague, Janice Brahney, Panya Lipovsky, Peter J. Haeussler, Brian Menounos

Watershed Sciences Faculty Publications

The Yukon–Alaska Highway corridor in southern Yukon is subject to geohazards ranging from landslides to floods and earthquakes on faults in the St. Elias Mountains and Shakwak Valley. Here we discuss the late Holocene seismic history of the Denali fault, located at the eastern front of the St. Elias Mountains and one of only a few known seismically active terrestrial faults in Canada. Holocene faulting is indicated by scarps and mounds on late Pleistocene drift and by tectonically deformed Pleistocene and Holocene sediments. Previous work on trenches excavated against the fault scarp near the Duke River reveals paleoseismic sediment disturbance …

Mapping Valley Bottom Confinement At The Network Scale, Gary R. O'Brien, Joseph Michael Wheaton, Kirstie Fryirs, William W. Macfarlane, Gary Brierley, Kelly Whitehead, Jordan T. Gilbert, Carol Volk

Watershed Sciences Faculty Publications

In this article, we demonstrate the application of a continuous confinement metric across entire river networks. Confinement is a useful metric for characterizing and discriminating valley setting. At the reach scale, valley bottom confinement is measured and quantified as the ratio of the length of channel confined on either bank by a confining margin divided by the reach length. The valley bottom is occupied by the contemporary floodplain and/or its channel(s); confining margins can be any landform or feature that makes up the valley bottom margin, such as bedrock hillslopes, terraces, fans, or anthropogenic features such as stopbanks or constructed …

Assessment Of The Effects Of Climate Change On Evapotranspiration With An Improved Elasticity Method In A Nonhumid Area, Lei Tian, Jiming Jin, Pute Wu, Guo-Yue Niu

Watershed Sciences Faculty Publications

Climatic elasticity is a crucial metric to assess the hydrological influence of climate change. Based on the Budyko equation, this study performed an analytical derivation of the climatic elasticity of evapotranspiration (ET). With this derived elasticity, it is possible to quantitatively separate the impacts of precipitation, air temperature, net radiation, relative humidity, and wind speed on ET in a watershed. This method was applied in the Wuding River Watershed (WRW), located in the center of the Yellow River Watershed of China. The estimated rate of change in ET caused by climatic variables is −10.69 mm/decade, which is close to the …

Quantifying The Impact Of Climate Change And Human Activities On Streamflow In A Semi-Arid Watershed With The Budyko Equation Incorporating Dynamic Vegetation Information, Lei Tian, Jiming Jin, Pute Wu, Guo-Yue Niu

Watershed Sciences Faculty Publications

Understanding hydrological responses to climate change and land use and land cover change (LULCC) is important for water resource planning and management, especially for water-limited areas. The annual streamflow of the Wuding River Watershed (WRW), the largest sediment source of the Yellow River in China, has decreased significantly over the past 50 years at a rate of 5.2 mm/decade. Using the Budyko equation, this study investigated this decrease with the contributions from climate change and LULCC caused by human activities, which have intensified since 1999 due to China’s Grain for Green Project (GFGP). The Budyko parameter that represents watershed characteristics …

Can The Desiccation Of Great Salt Lake Be Stopped?, Wayne A. Wurtsbaugh, Craig Miller, Sarah E. Null, R. Justin Derose, Peter Wilcock

Watershed Sciences Faculty Publications

Great Salt Lake is a terminal lake, with its watershed in the Wasatch and Uinta Mountains of Utah, Wyoming and Idaho. Like all terminal lakes, the water inflows are balanced only by evaporative loss from its surface—when inflows decrease the lake shrinks until evaporation matches that inflow.

Sustaining Wetlands To Mitigate Disasters And Protect People, Joanna Endter-Wada, Karin M. Kettenring, Ariana E. Sutton-Grier

Watershed Sciences Faculty Publications

Hurricanes, flooding, droughts. Weather‐related disasters are dominating news cycles and causing widespread destruction, most recently with Typhoon Mangkhut and Hurricane Florence. The US had the most catastrophic hurricane season on record in 2017, with hundreds of billions of dollars in estimated damages. California is experiencing unprecedented tragedies from widespread wildfires and increased vulnerability to storms. Disasters that were once uncommon appear to be the new norm globally, and evidence suggests the frequency and impacts of extreme events will increase further with climate change.

A Network Model For Primary Production Highlights Linkages Between Salmonid Populations And Autochthonous Resources, W. Carl Saunders, Nicolaas Bouwes, Peter Mchugh, Chris E. Jordan

Watershed Sciences Faculty Publications

Spatial variation in fish densities across river networks suggests that the influence of food and habitat resources on assemblages varies greatly throughout watersheds. Conceptual models predict that in situ primary production should vary with river characteristics, but the influence of autochthonous resource availability on the capacity for river reaches to support fish is poorly understood. We estimated primary production throughout the South Fork and Middle Fork of the John Day River, Oregon, by measuring diel cycles in dissolved oxygen (DO) during July 2013. Using these data, we (1) evaluated the extent to which juvenile salmonid abundance and resource limitation correlated …

3d Photogrammetry Quantifies Growth And External Erosion Of Individual Coral Colonies And Skeletons, Renata Ferrari, Will F. Figueira, Morgan S. Pratchett, Tatiana Boube, Arne Adam, Tania Kobelkowsky-Vidrio, Steve S. Doo, Trisha Brooke Atwood, Maria Byrne

Watershed Sciences Faculty Publications

Growth and contraction of ecosystem engineers, such as trees, influence ecosystem structure and function. On coral reefs, methods to measure small changes in the structure of microhabitats, driven by growth of coral colonies and contraction of skeletons, are extremely limited. We used 3D reconstructions to quantify changes in the external structure of coral colonies of tabular Acropora spp., the dominant habitat-forming corals in shallow exposed reefs across the Pacific. The volume and surface area of live colonies increased by 21% and 22%, respectively, in 12 months, corresponding to a mean annual linear extension of 5.62 cm yr⁻¹ (±1.81 SE). …

Accounting For Spatial And Temporal Variation In Macroinvertebrate Community Abundances When Measuring The Food Supply Of Stream Salmonids, Nicholas Weber, Nicolaas Bouwes, Chris Jordan

Watershed Sciences Faculty Publications

The goal of salmonid habitat monitoring programs is to measure habitat attributes linked to salmonid productivity based on protocols that have sufficient precision to detect environmental variation at relevant spatial and temporal scales. Benthic macroinvertebrate community composition often is evaluated as part of habitat monitoring and assessment protocols, despite a lack of direct relationships between benthic composition and salmonid production. Macroinvertebrate drift provides a direct measure of the food resources available to stream salmonids, but drift is rarely evaluated as part of habitat monitoring protocols. This reluctance may stem from the complex spatial and temporal variability inherent in macroinvertebrate drift …

Accounting For Spatial And Temporal Variation In Macroinvertebrate Community Abundances When Measuring The Food Supply Of Stream Salmonids, Nicholas Weber, Nicolaas Bouwes, Chris Jordan

Watershed Sciences Faculty Publications

The goal of salmonid habitat monitoring programs is to measure habitat attributes linked to salmonid productivity based on protocols that have sufficient precision to detect environmental variation at relevant spatial and temporal scales. Benthic macroinvertebrate community composition often is evaluated as part of habitat monitoring and assessment protocols, despite a lack of direct relationships between benthic composition and salmonid production. Macroinvertebrate drift provides a direct measure of the food resources available to stream salmonids, but drift is rarely evaluated as part of habitat monitoring protocols. This reluctance may stem from the complex spatial and temporal variability inherent in macroinvertebrate drift …

Rapid Surface-Water Volume Estimations In Beaver Ponds, Daniel J. Karran, Cherie J. Westbrook, Joseph Michael Wheaton, Carol A. Johnston, Angela Bedard-Haughn

Watershed Sciences Faculty Publications

Beaver ponds are surface-water features that are transient through space and time. Such qualities complicate the inclusion of beaver ponds in local and regional water balances, and in hydrological models, as reliable estimates of surface-water storage are difficult to acquire without time- and labour-intensive topographic surveys. A simpler approach to overcome this challenge is needed, given the abundance of the beaver ponds in North America, Eurasia, and southern South America. We investigated whether simple morphometric characteristics derived from readily available aerial imagery or quickly measured field attributes of beaver ponds can be used to approximate surface-water storage among the range …

Wildfire In Utah: The Physical And Economic Consequences Of Wildfire, Paul Mark Jakus, Man-Keun Kim, Randy S. Martin, Ian Hammond, Edd Hammill, Nancy O. Mesner, Jacob Stout

Watershed Sciences Faculty Publications

PRELUDE

On June 26, 2012 a lightning strike ignited a wildfire in the Manti-La Sal National Forest of central Utah’s Carbon and Emery counties (Figure P.1). By the time the Seeley wildfire was contained three weeks later, some 48,000 acres of federal, state, and private land had been burned and $8.7 million in suppression costs expended (Styler 2012). According to the Monitoring Trends in Burn Severity (MTBS.gov) project, nearly one-third of the acreage was severely burned, damaging vegetation and soils for years to come. Severe burns vastly increase the erosion potential of burnt landscapes, and the steep lands of Huntington …

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 …