Ultra‐high‐resolution mapping of biocrusts with Unmanned Aerial Systems
Caroline Havrilla, Miguel L. Villarreal, Jacob DiBiase, Michael C. Duniway, Nichole Barger
2020, Remote Sensing in Ecology and Conservation (6) 441-456
Biological soil crusts (biocrusts) occur in drylands globally where they support ecosystem functioning by increasing soil stability, reducing dust emissions and modifying soil resource availability (e.g. water, nutrients). Determining biocrust condition and extent across landscapes continues to present considerable challenges to scientists and land managers. Biocrusts...
Ecohydrological responses to surface flow across borders: Two decades of changes in vegetation greenness and water use in the riparian corridor of the Colorado River Delta
Pamela L. Nagler, Armando Barreto-Muñoz, Sattar Chavoshi Borujeni, Christopher J. Jarchow, Marth M. Gómez‐Sapiens, Hamideh Nouri, Stefanie M. Herrmann, Kamel Didan
2020, Hydrological Processes (34) 4851-4883
Hydrological and bioclimatic processes that lead to drought may stress plants and wildlife, restructure plant community type and architecture, increase monotypic stands and bare soils, facilitate the invasion of non‐native plant species and accelerate soil erosion. Our study focuses on the impact of a paucity of Colorado River surface flows...
Application of a new species-richness based flow ecology framework for assessing flow reduction effects on aquatic communities
Jennifer Rapp, Robert W. Burgholzer, Joseph D Kleiner, Durelle R Scott, Elaina M Passero
2020, Journal of the American Water Resources Association (6) 967-980
Water‐resources managers are challenged with maintaining a balance among beneficial uses throughout river networks and need robust means of assessing potential risks to aquatic life resulting from flow alterations. This study generated ecological limit functions from species‐streamflow relations to quantify potential fish richness response to flow...
Unfamiliar territory: Emerging themes for ecological drought research and management
Shelley D. Crausbay, Julio L. Betancourt, John B. Bradford, Jennifer M. Cartwright, William C. Dennison, Jason B. Dunham, Carolyn Armstrong Enquist, Abby G. Frazier, Kimberly R. Hall, Jeremy S. Littell, Charlie H. Luce, Richard Palmer, Aaron R. Ramirez, Imtiaz Rangwala, Laura Thompson, Brianne M. Walsh, Shawn Carter
2020, One Earth (3) 337-353
Novel forms of drought are emerging globally, due to climate change, shifting teleconnection patterns, expanding human water use, and a history of human influence on the environment that increases the probability of transformational ecological impacts. These costly ecological impacts cascade to human communities, and understanding this changing drought landscape is...
A new decision support tool for collaborative adaptive vegetation management in northern Great Plains national parks
Isabel W. Ashton, Amy Symstad, Heather Baldwin, Max Post van der Burg, Steven Bekedam, Erin Borgman, Milton Haar, Terri Hogan, Stephanie Rockwood, Daniel J Swanson, Carmen Thomson, Cody Wienk
2020, Parks Stewardship Forum (3)
National Park Service (NPS) units in the northern Great Plains (NGP) were established to preserve and interpret the history of America, protect and showcase unusual geology and paleontology, and provide a home for vanishing large wildlife. A unifying feature among these national parks, monuments, and historic sites is mixed-grass prairie,...
Landsat Collection 2 geometric calibration updates
R. Rengarajan, Michael J. Choate, James C. Storey, Shannon Franks, Esad Micijevic
2020, Conference Paper, Proceedings: Earth observing systems XXV
The U.S. Geological Survey (USGS) changed the management and delivery of Landsat products to the public in its archive through the implementation of Collections. The Collections process ensures consistent data quality through time and across all the Landsat sensors with a few modifications to the metadata. The consistent data products...
Comparability and reproducibility of biomarker ratio values measured by GC-QQQ-MS
Katherine L. French, Arne Leider, Christian Hallmann
2020, Organic Geochemistry (150)
The Norwegian Geochemical Standard North Sea Oil-1 was analyzed by gas chromatography triple quadrupole mass spectrometry (GC-QQQ-MS) on two instruments using independently developed analytical methods. Biomarker ratios determined by GC-QQQ-MS were compared to each other and to previously reported values determined by gas chromatography single quadrupole mass spectrometry (GC-Q-MS) or...
How and why is the timing and occurrence of seasonal migrants in the Gulf of Maine changing due to climate?
Adrian Jordaan, Daniel Pendleton, Chris Sutherland, Michelle Staudinger
2020, Report
Plants and animals undergo certain recurring life-cycle events, such as migrations between summer and winter habitats or the annual blooming of plants. Known as phenology, the timing of these events is very sensitive to changes in climate (and changes in one species’ phenology can impact entire food webs and ecosystems)....
Potential impacts of mercury released from thawing permafrost
Kevin Schaefer, Yasin Elshorbany, Elchin Jafarov, Paul F. Schuster, Robert G. Striegl, Kimberly P. Wickland, Elsie M. Sunderland
2020, Nature-Communications (11)
Mercury (Hg) is a naturally occurring element that bonds with organic matter and, when converted to methylmercury, is a potent neurotoxicant. Here we estimate potential future releases of Hg from thawing permafrost for low and high greenhouse gas emissions scenarios using a mechanistic model. By 2200, the high emissions scenario...
Position-specific distribution of hydrogen isotopes in natural propane: Effects of thermal cracking, equilibration and biodegradation
Hao Xie, Camilo Ponton, Michael Formolo, Michael Lawson, Geoffrey S. Ellis, Michael Lewan, Alexandre A. Ferreira, Erica T. Morais, Andre D. Spigolon, Alex L. Sessions, John M. Eiler
2020, Geochimica et Cosmochimica Acta (290) 235-256
Intramolecular isotope distributions, including isotope clumping and position specific fractionation, can provide proxies for the formation temperature and formation and destruction pathways of molecules. In this study, we explore the position-specific hydrogen isotope distribution in propane. We analyzed propane samples from...
Wildfire risk and hazardous fuel reduction treatments along the US-Mexico border: A review of the science (1985-2019)
Katherine M. Laushman, Seth M. Munson, Timothy N. Titus
2020, Air, Soil and Water Research (13)
The ecosystems along the border between the United States and Mexico are at increasing risk to wildfire due to interactions among climate, land-use, and fuel loads. A wide range of fuel treatments have been implemented to mitigate wildfire and its threats to valued resources, yet we have...
Rainfall triggers more deep-seated landslides than Cascadia earthquakes in the Oregon Coast Range, USA
Sean R LaHusen, Alison R Duvall, Adam M. Booth, Alex R. Grant, Benjamin A Mishkin, David R. Montgomery, William Struble, Joshua J. Roering, Joseph Wartman
2020, Science Advances (6)
The coastal Pacific Northwest USA hosts thousands of deep-seated landslides. Historic landslides have primarily been triggered by rainfall, but the region is also prone to large earthquakes on the 1100-km-long Cascadia Subduction Zone megathrust. Little is known about the number of landslides triggered by these earthquakes because the last magnitude...
Improving the accessibility and transferability of machine learning algorithms for identification of animals in camera trap images: MLWIC2
Michael A. Tabak, Mohammad S. Norouzzadeh, David W. Wolfson, Erica J. Newton, Raoul K. Boughton, Jacob S. Ivan, Eric Odell, Eric S. Newkirk, Reesa Y. Conrey, Jennifer L. Stenglein, Fabiola Iannarilli, John Erb, Ryan K. Brook, Amy J. Davis, Jesse S. Lewis, Daniel P. Walsh, James C Beasley, Kurt C. Vercauteren, Jeff Clune, Ryan S. Miller
2020, Ecology and Evolution (10) 10374-10383
Motion‐activated wildlife cameras (or “camera traps”) are frequently used to remotely and noninvasively observe animals. The vast number of images collected from camera trap projects has prompted some biologists to employ machine learning algorithms to automatically recognize species in these images, or at least filter‐out images...
Accounting for temporal variability of streamflow in estimates of travel time
Christopher P. Konrad, Noah Schmadel, Judson Harvey, Gregory E. Schwarz, Jesus Gomez-Velez, Elizabeth W. Boyer, Durelle Scott
2020, Frontiers in Water (2)
Retention, processing, and transport of solutes and particulates in stream corridors are influenced by the travel time of streamflow through stream channels, which varies dynamically with discharge. The effects of streamflow variability across sites and over time cannot be addressed by time-averaged models if parameters are based solely on...
Variations in community evacuation potential related to average return periods in probabilistic tsunami hazard analysis
Nathan J. Wood, Jeff Peters, Rick I. Wilson, Jason T. Sherba, Kevin Henry
2020, International Journal of Disaster Risk Reduction (50)
Tsunami risk management requires strategies that can address multiple sources with different recurrence intervals, wave-arrival times, and inundation extents. Probabilistic tsunami hazard analysis (PTHA) provides a structured way to integrate multiple sources, including the uncertainties due to the natural variability and...
Modeling the spatial dynamics of marsh ponds in New England salt marshes
G. Mariotti, A. Spivak, S.Y. Luk, G. Ceccherini, M. Tyrrell, Meagan Gonneea Eagle
2020, Geomorphology (365)
Ponds are common features on salt marshes, yet it is unclear how they affect large-scale marsh evolution. We developed a spatially explicit model that combines cellular automata for pond formation, expansion, and drainage, and partial differential equations for elevation dynamics. We...
Scenarios for valuing sample information in natural resources
Byron K. Williams, Ellie Brown
2020, Methods in Ecology and Evolution (11) 1534-1549
Uncertainty is ubiquitous in natural resource systems, science and management. Sample data are obtained in order to reduce uncertainty, thereby increasing knowledge and improving resource management, but sampling always comes at a cost of some sort. Is that cost worthwhile? Analysis of the value of sample information (VSI) addresses...
Land-use change and future water demand in California’s central coast
Tamara Wilson, Nathan D. Van Schmidt, Ruth Langridge
2020, Land (9) 322-343
Understanding future land-use related water demand is important for planners and resource managers in identifying potential shortages and crafting mitigation strategies. This is especially the case for regions dependent on limited local groundwater supplies. For the groundwater dependent Central Coast of California, we developed two scenarios of future land use...
Using boosted regression tree models to predict salinity in Mississippi embayment aquifers, central United States
Katherine J. Knierim, James A. Kingsbury, Connor J. Haugh, Katherine Marie Ransom
2020, Journal of American Water Resources Association (56) 1029
High salinity limits groundwater use in parts of the Mississippi embayment. Machine learning was used to create spatially continuous and three‐dimensional predictions of salinity across drinking‐water aquifers in the embayment. Boosted regression tree (BRT) models, a type of machine learning, were used to predict specific conductance (SC) and chloride (Cl),...
The roles of storminess and sea level rise in decadal barrier island evolution
Davina Passeri, P. Soupy Dalyander, Joseph W. Long, Rangley C. Mickey, Robert L. Jenkins III, David M. Thompson, Nathaniel G. Plant, Elizabeth Godsey, Victor Gonzalez
2020, Geophysical Research Letters (47)
Models of alongshore sediment transport during quiescent conditions, storm‐driven barrier island morphology, and poststorm dune recovery are integrated to assess decadal barrier island evolution under scenarios of increased sea levels and variability in storminess (intensity and frequency). Model results indicate barrier island response regimes of keeping pace, narrowing, flattening, deflation...
Hydro-climatic drought in the Delaware River Basin
Gregory J. McCabe, David M. Wolock
2020, Journal of the American Water Resources Association (56) 981-994
The Delaware River Basin (DRB) supplies water to approximately 15 million people and is essential to agriculture and industry. In this study, a monthly water balance model is used to compute monthly water balance components (i.e., potential evapotranspiration, actual evapotranspiration, and runoff [R]) for the DRB...
Geomagnetism Program research plan, 2020–2024
Jeffrey J. Love, Anna Kelbert, Benjamin S. Murphy, E. Joshua Rigler, Kristen A. Lewis
2020, Circular 1469
The Geomagnetism Program of the U.S. Geological Survey (USGS) monitors geomagnetic field variation through operation of a network of observatories across the United States and its territories, and it pursues scientific research needed to estimate and assess geomagnetic and geoelectric hazards. Over the next five years (2020–2024 inclusive) and in...
Habitat suitability and ecological associations of two non-native ungulate species on the Hawaiian island of Lanai
Steve C. Hess, Lucas Berio Fortini, Christina Leopold, Jacob Muise, Jonathan Sprague
2020, Hawaii Cooperative Studies Unit Technical Report Series 91
The ability to effectively manage game species for specific conservation objectives is often limited by the scientific understanding of their distribution and abundance. This is especially true in Hawai‘i where introduced game mammals are poorly studied and have low value relative to native species in other states. We modeled the...
Lead speciation, bioaccessibility and source attribution in Missouri's Big River watershed
Matthew Noerpel, Michael J. Pribil, Danny Rutherford, Preston Law, Karen Bradham, Clay Nelson, Rob Weber, Gene Gunn, Kirk G. Scheckel
2020, Applied Geochemistry (123)
The Southeast Missouri Lead District is among the most productive lead deposits exploited in modern times. Intensive mining conducted prior to regulations resulted in a legacy of lead contaminated soil, large piles of mine tailings and elevated childhood blood lead levels. This study seeks to identify the source of the...
Habitat use by tiger prey in Thailand’s Western Forest Complex: What will it take to fill a half-full tiger landscape?
Pornkamol Jornburom, Somphot Duangchantrasiri, Sitthichai Jinamoy, Anak Pattanavibool, James E. Hines, Todd W. Arnold, John Fieberg, James L D Smith
2020, Journal for Nature Conservation (58)
Tiger populations are declining globally, and depletion of major ungulate prey is an important contributing factor. To better understand factors affecting prey distribution in Thailand’s Western Forest Complex (WEFCOM), we conducted sign surveys for gaur (Bos gaurus), banteng (Bos javanicus), and sambar (Rusa...
