Decoupling of species and plant communities of the U.S. Southwest: A CCSM4 climate scenario example
Kathryn A. Thomas, Brett A. Stauffer, Christopher J. Jarchow
2023, Ecosphere (14)
Climate change is predicted to alter the current climate suitability under which plant species and communities occur. Predictions of change have focused on individual species or entire communities, but theory indicates plants will not respond uniformly to climate change within or between communities. We developed models...
Effect of thermal and mechanical processes on hydraulic transmissivity evolution
Tamara Nicole Jeppson, David A. Lockner, Joshua M. Taron, Diane E. Moore, Brian D. Kilgore, Nicholas M. Beeler, Stephen H. Hickman
2023, Conference Paper, Proceedings, 48th Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California, February 6-8, 2023
Fracture healing is a critical component of enhanced geothermal systems, the earthquake cycle, and induced seismicity. Accordingly, there is significant interest in understanding the process of healing and its effects on fluid transport. The creation, reactivation, and sustainability of fracture networks depend on complex coupling among thermal, hydraulic, mechanical, and...
A comparison of direct & indirect survey methods for estimating colonial nesting waterbird populations
Diann Prosser, Jeffery D. Sullivan, Christopher J. Gilbert, David F. Brinker, Peter C. McGowan, Carl R. Callahan, Ben Hutzell, Laurence E. Smith
2023, Waterbirds (45) 189-198
Population estimates derived from monitoring efforts can be sensitive to the survey method selected, potentially leading to biased estimates and low precision relative to true population size. While small unmanned aerial systems (UAS) present a unique opportunity to survey avian populations while limiting disturbance, relatively...
Genetic diversity and IUCN Red List status
Chloe Schmidt, Sean M. Hoban, Margaret Hunter, Ivan Paz-Vinas, Colin J. Garroway
2023, Conservation Biology (37)
The International Union for Conservation of Nature (IUCN) Red List is an important and widely used tool for conservation assessment. The IUCN uses information about a species’ range, population size, habitat quality and fragmentation levels, and trends in abundance to assess extinction risk. Genetic...
eDNA Metabarcoding Analyses of Diet in Yellow-Billed Loons of Northern Alaska
Damian M. Menning, Brian D. Uher-Koch, Melanie J. Flamme, Trey Simmons, Joel Schmutz, Sandra Talbot
2023, Waterbirds (45) 159-166
Environmental DNA is a burgeoning tool used to address wide-ranging scientific questions, including determining diets of difficult-to-sample predators. Loons are large piscivorous diving birds that capture and consume prey underwater, making it nearly impossible to visually determine their diet via observation alone. Identifying species' diets...
Mapping ancient sedimentary organic matter molecular structure at nanoscales using optical photothermal infrared spectroscopy
Aaron M. Jubb, Martha Stokes, Ryan J. McAleer, Paul C. Hackley, Eoghan Dillion, Jing Qu
2023, Organic Geochemistry (177)
Elucidating the molecular structure of sedimentary organic matter (SOM) is key to understanding petroleum generation processes, as well as ancient sedimentary environments. SOM structure is primarily controlled by biogenic source material (e.g., marine vs. terrigenous), depositional conditions, and subsurface thermal history. Additional factors, e.g., strain, may also impact the...
Declines in body size of sockeye salmon associated with increased competition in the ocean
Jan Ohlberger, Timothy Joseph Cline, Daniel Schindler, Bert Lewis
2023, Proceedings of the Royal Society B (290)
Declining body sizes have been documented for several species of Pacific salmon; however, whether size declines are caused mainly by ocean warming or other ecological factors, and whether they result primarily from trends in age at maturation or changing growth rates remain poorly understood. We quantified changes in mean body...
The Volcanic Hazard Maps Database: An initiative of the IAVCEI Commission on Volcanic Hazards and Risk
Sarah E. Ogburn, Danielle Charlton, Diana Norgaard, Heather M. Wright, Eliza S. Calder, Jan Lindsay, John W. Ewert, Shinji Takarada, Yasuhisa Tajima
2023, Journal of Applied Volcanology (12)
In this work we present the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) Commission on Volcanic Hazards and Risk (CVHR) Volcanic Hazard Maps Database and the accompanying volcanichazardmaps.org website. Using input from a series of IAVCEI CVHR Working Group on Hazard...
Applications of nonergodic site response models to ShakeAlert case studies in the Los Angeles area
Rongrong Lin, Grace Alexandra Parker, Jeffrey J. McGuire, Annemarie S. Baltay Sundstrom
2023, Bulletin of the Seismological Society of America (113) 1324-1343
In this study, we explore whether the Parker and Baltay (2022) site response models for the Los Angeles (LA) basin region can improve ground‐motion forecasts in the U.S. Geological Survey ShakeAlert earthquake early warning system (hereafter ShakeAlert). We implement the peak ground acceleration and peak ground velocity site...
Colored shaded-relief bathymetric map and orthomosaic from structure-from-motion quantitative underwater imaging device with five cameras of the Lake Tahoe floor, California
Gerald A. Hatcher, Jonathan A. Warrick, Peter Dartnell
2023, Scientific Investigations Map 3501
This two-sheet publication displays a high-resolution colored shaded-relief bathymetric map (sheet 1) and orthomosaic (sheet 2) of part of the Lake Tahoe floor in California generated from a U.S. Geological Survey towed surface vehicle with multiple downward-looking underwater cameras. The system is named the Structure-from-Motion Quantitative Underwater Imaging Device with...
Bluegill population demographics as related to abiotic and biotic factors in Florida lakes
Andrew Kenneth Carlson, Mark V. Hoyer
2023, Fishes (8)
Research on Bluegills, Lepomis macrochirus R., is abundant but typically focuses on water bodies with similar environmental conditions. We assessed Bluegill density, relative abundance (catch per unit effort [CPUE] by electrofishing), growth, and size structure in 60 lakes with wide-ranging surface areas (2–12,412 ha), trophic states (oligotrophic–hypereutrophic), and macrophyte abundances (0.3–100...
An evaluation of multistate occupancy models for estimating relative abundance and population trends
Valerie A. Steen, Adam Duarte, James Peterson
2023, Ecological Modelling (478)
Detecting spatiotemporal changes in the abundances of organisms is key to effectively conserving species. While indices of abundance have long been used, there has been a shift toward model-based estimators that account for the detection process. Popular approaches including traditional occupancy models and N-mixture models entail tradeoffs. The traditional occupancy...
Support for the fasting endurance hypothesis of partial migration in a nearshore seabird
Bradley P. Wilkinson, Patrick G.R. Jodice
2023, Ecosphere (14)
Partial migration occurs when only a fraction of a population migrates instead of all individuals. Considered an evolutionary precursor to full migration, understanding why some individuals choose to undertake migration while others do not may serve to inform general migratory theory. While several hypotheses currently exist for explaining the maintenance...
Anthropogenic subsidies influence resource use during a mange epizootic in a desert coyote population
Craig D. Reddell, Gary W. Roemer, David K. Delaney, Talesha Karish, James W. Cain III
2023, Oecologia (201) 435-447
Colonization of urban areas by synanthropic wildlife introduces novel and complex alterations to established ecological processes, including the emergence and spread of infectious diseases. Aggregation at urban resources can increase disease transfer, with wide-ranging species potentially infecting outlying populations. The garrison at the National Training Center, Fort Irwin, California, USA,...
A review of common natural disasters as analogs for asteroid impact effects and cascading hazards
Timothy N. Titus, D. G. Robertson, Joel B. Sankey, Larry G. Mastin, Francis K. Rengers
2023, Natural Hazards (116) 1355-1402
Modern civilization has no collective experience with possible wide-ranging effects from a medium-sized asteroid impactor. Currently, modeling efforts that predict initial effects from a meteor impact or airburst provide needed information for initial preparation and evacuation plans, but longer-term cascading hazards are not typically considered. However, more common natural disasters,...
From bottom-up to top-down control of invertebrate herbivores in a retrogressive chronosequence
Anne Kempel, Eric Allan, Martin M. Gossner, Malte Jochum, James Grace, David A. Wardle
2023, Ecology Letters (26) 411-424
In the long-term absence of disturbance, ecosystems often enter a decline or retrogressive phase which leads to reductions in primary productivity, plant biomass, nutrient cycling and foliar quality. However, the consequences of ecosystem retrogression for higher trophic levels such as herbivores and predators, are less clear. Using a post-fire forested...
Six years of fluvial response to a large dam removal on the Carmel River, California, USA
Amy E. East, Lee R. Harrison, Douglas P. Smith, Joshua B. Logan, Rosealea Bond
2023, Earth Surface Processes and Landforms (48) 1487-1501
Measuring river response to dam removal affords a rare, important opportunity to study fluvial response to sediment pulses on a large field scale. We present a before–after/control–impact study of the Carmel River, California, measuring fluvial geomorphic and grain-size evolution over 8 years, six of which postdated removal of a 32 m-high...
Increasing Alaskan river discharge during the cold season is driven by recent warming
D Blaskey, Joshua C. Koch, M. Gooseff, A. C. Newman, Yang Cheng, Jonathan A. O’Donnell, K Musselman
2023, Environmental Research Letters (18)
Arctic hydrology is experiencing rapid changes including earlier snow melt, permafrost degradation, increasing active layer depth, and reduced river ice, all of which are expected to lead to changes in stream flow regimes. Recently, long-term (>60 years) climate reanalysis and river discharge observation data have become available....
Upwelling, climate change, and the shifting geography of coral reef development
Victor Rodriguez-Ruano, Lauren Toth, Ian C. Enochs, Carly J. Randall, Richard B. Aronson
2023, Scientific Reports (13)
The eastern tropical Pacific is oceanographically unfavorable for coral-reef development. Nevertheless, reefs have persisted there for the last 7000 years. Rates of vertical accretion during the Holocene have been similar in the strong-upwelling Gulf of Panamá (GoP) and the adjacent, weak-upwelling Gulf of Chiriquí (GoC); however, seasonal...
Detection and monitoring of small-scale diamond and gold mining dredges using synthetic aperture radar on the Kadéï (Sangha) River, Central African Republic
Marissa Ann Alessi, Peter G. Chirico, Sindhuja Sunder, Kelsey L. O’Pry
2023, Remote Sensing (15)
Diamond and gold mining has been practiced by artisanal miners in the Central African Republic (CAR) for decades. The recent introduction of riverine dredges indicates a transition from artisanal/manual digging and sorting techniques to small-scale mining methods. This study implements a remote sensing analysis of Synthetic Aperture Radar (SAR)...
Stabilising effects of karstic groundwater on stream fish communities
Nathaniel P. Hitt, Karli M. Rogers, Karmann G. Kessler, Martin A. Briggs, Jennifer H. Fair
2023, Ecology of Freshwater Fish (32) 538-551
Although groundwater exchange processes are known to modulate atmospheric influences on stream temperature and flow, the implications for ecological stability are poorly understood. Here, we evaluated temporal change in stream fish communities across a gradient of groundwater influence defined by karst terrain (carbonate parent materials) within...
Sierra Nevada amphibians demonstrate stable occupancy despite precipitation volatility in the early 21st Century
Brian J. Halstead, Patrick M. Kleeman, Jonathan P. Rose, Gary M. Fellers
2023, Frontiers in Ecology and Evolution (10)
Climate can have a strong influence on species distributions, and amphibians with different life histories might be affected by annual variability in precipitation in different ways. The Sierra Nevada of California, United States, experienced some of the driest and wettest years on record in the early 21st Century, with...
When less is more: How increasing the complexity of machine learning strategies for geothermal energy assessments may not lead toward better estimates
Stanley Paul Mordensky, John Lipor, Jacob DeAngelo, Erick R. Burns, Cary Ruth Lindsey
2023, Geothermics (110)
Previous moderate- and high-temperature geothermal resource assessments of the western United States utilized data-driven methods and expert decisions to estimate resource favorability. Although expert decisions can add confidence to the modeling process by ensuring reasonable models are employed, expert decisions also introduce human and, thereby, model bias. This bias...
Regolith of the crater floor units, Jezero crater, Mars: Textures, composition and implications for provenance
Alicia Vaughan, Michelle E. Minitti, Emily L. Cardarelli, Jeffrey R. Johnson, Linda C. Kah, Paolo Pilleri, Mellisa S. Rice, Mark Sephton, Briony H. N. Horgan, Roger C. Wiens, R. Aileen Yingst, Maria-Paz Zorzano Mier, Ryan B. Anderson, James F. III Bell, Adrian J. Brown, Edward A. Cloutis, Agnes Cousin, Kenneth E. Herkenhoff, Elisabeth M. Housrath, Alexander G. Hayes, Kjartan M. Kinch, Marco Merusi, Chase C. Million, Robert Sullivan, Sandra M. Siljestrom, Michael St. Clair
2023, JGR-Planets (128)
A multi-instrument study of the regolith of Jezero crater floor units by the Perseverance rover has identified three types of regolith: fine-grained, coarse-grained, and mixed-type. Mastcam-Z, WATSON, and SuperCam RMI were used to characterize regolith texture, particle size, and roundedness where possible. Mastcam-Z multispectral and SuperCam LIBS...
Groundwater quality near the Montebello Oil Field, Los Angeles County, California
Jennifer S. Stanton, Michael Land, Matthew K. Landon, David H. Shimabukuro, Peter B. McMahon, Tracy A. Davis, Andrew G. Hunt, Theron A. Sowers
2023, Scientific Investigations Report 2022-5128
Groundwater quality and potential sources and migration pathways of chemical constituents associated with hydrocarbon-bearing formations were assessed by the U.S. Geological Survey for the California State Water Resources Control Board Oil and Gas Regional Monitoring Program (RMP). Groundwater samples were collected as part of the RMP from 21 preexisting wells...
