Alternative stable states in inherently unstable systems
David M. Mushet, Owen P. McKenna, Kyle McLean
2020, Ecology and Evolution (10) 843-850
Alternative stable states are nontransitory states within which communities can exist. However, even highly dynamic communities can be viewed within the framework of stable‐state theory if an appropriate “ecologically relevant” time scale is identified. The ecologically relevant time scale for dynamic systems needs to conform to the amount of time...
From theory to experiments for testing the proximate mechanisms of mast seeding: An agenda for an experimental ecology
M. Bogdziewicz, Davide Ascoli, Andrew Hacket-Pain, W. D. Koenig, Ian Pearse, Mario B. Pesendorfer, A. Satake, P. Thomas, Giorgio Vacchiano, T. Wohlgemuth, A. Tanentzap
2020, Ecology Letters (23) 210-220
Highly variable and synchronised production of seeds by plant populations is called masting and is implicated in many important ecological processes, but how it arises remains poorly understood. The lack of experimental studies prevents underlying mechanisms from being explicitly tested, and thereby precludes meaningful predictions on the consequences of changing...
Geophysical characterization of a Proterozoic REE terrane at Mountain Pass, eastern Mojave Desert, California
Kevin Denton, David A. Ponce, Jared R. Peacock, David M. Miller
2020, Geosphere (16) 456-471
Mountain Pass, California (USA), located in the eastern Mojave Desert, hosts one of the world’s richest rare earth element (REE) deposits. The REE-rich terrane occurs in a 2.5-km-wide, northwest-trending belt of Mesoproterozoic (1.4 Ga) stocks and dikes, which intrude a larger Paleoproterozoic (1.7 Ga) metamorphic block that extends ∼10 km...
Shift in the Raman symmetric stretching band of N2, CO2, and CH4 as a function of temperature, pressure, and density
D. Matthew Sublett, Eszter Sendula, Hector Lamadrid, Matthew Steele-MacInnis, Georg Spiekermann, Robert Burruss, Robert J. Bodnar
2020, Journal of Raman Spectroscopy (51) 555-568
The Raman spectra of pure N2, CO2, and CH4 were analyzed over the range 10 to 500 bars and from −160°C to 200°C (N2), 22°C to 350°C (CO2), and −100°C to 450°C (CH4). At constant temperature, Raman peak position, including the more intense CO2 peak (ν+), decreases (shifts to lower wave number)...
Postmortem evaluation of reintroduced migratory whooping cranes (Grus americana) in eastern North America
Taylor J. Yaw, Kimberli J.G. Miller, Julia S. Lankton, Barry K. Hartup
2020, Wildlife Disease (56) 673-678
We reviewed necropsy records of 124 Whooping Cranes (Grus americana) recovered following reintroduction of 268 individuals from 2001 to 2016 in the eastern US. Causes of death were determined in 62% (77/124) of cases facilitated by active monitoring that limited decomposition and scavenging artifact. The greatest proportions of mortality were...
The method controls the story - Sampling method impacts on the detection of pore-water nitrogen concentrations in streambeds
Sophie Comer-Warner, Julia LA Knapp, Phillip J Blaen, Megan Klaar, Felicity Shelley, Jay P. Zarnetske, Joseph Lee-Cullen, Silvia Folegot, Marie Kurz, Jorg Lewandowski, Judson Harvey, Adam Ward, Clara Mendoza-Lera, Sami Ullah, Thibault Datry, Nicholas Kettridge, Daren Gooddy, Jennifer Drummond, Eugenia Marti, Alexander Milner, David Hannah, Stefan Krause
2020, Science of the Total Environment (709)
Biogeochemical gradients in streambeds are steep and can vary over short distances often making adequate characterisation of sediment biogeochemical processes challenging. This paper provides an overview and comparison of streambed pore-water sampling methods, highlighting their capacity to address gaps in our understanding of streambed biogeochemical processes. This work reviews...
The relative importance of wetland area versus habitat heterogeneity for promoting species richness and abundance of wetland birds in the Prairie Pothole Region, USA
Lisa H. Elliott, Lawrence Igl, Douglas H. Johnson
2020, The Condor (122)
Recent work has suggested that a tradeoff exists between habitat area and habitat heterogeneity, with a moderate amount of heterogeneity supporting greatest species richness. Support for this unimodal relationship has been mixed and has differed among habitats and taxa. We examined the relationship between habitat heterogeneity and species richness after...
Future losses of playa wetlands decrease network structure and connectivity of the Rainwater Basin, Nebraska
Bram H.F. Verheijen, Dana M. Varner, David A. Haukos
2020, Landscape Ecology (35) 453-467
ContextThe Rainwater Basin in south-central Nebraska once supported a complex network of ~ 12,000 spatially-isolated playa wetlands, but ~ 90% have been lost since European settlement. Future losses are likely and expected reductions in connectivity could further isolate populations, increasing local extinction rates of many wetland species. However, to what extent future...
Variation of annual apparent survival and detection rates with age, year, and individual identity in male Weddell seals (Leptonychotes weddellii) from long-term mark-recapture data
Jamie L. Brusa, Jay J. Rotella, Robert A. Garrott, J. Terrill Paterson, William Link
2020, Population Ecology (62) 134-150
Exploring age- and sex-specific survival rates provides insight regarding population behavior and life-history trait evolution, but many population studies exclude males. Accordingly, our understanding of how age-specific patterns of survival, including actuarial senescence, compare between the sexes remains inadequate. Using 35 years of mark-recapture data for 7,516...
Simulation of post-hurricane impact on invasive species with biological control management
Linhao Xu, Marya Claire Zdechlik, Melissa C. Smith, Min B. Rayamajhi, Don DeAngelis, Bo Zhang
2020, Discrete & Continuous Dynamical Systems-A (40) 4059-4071
Understanding the effects of hurricanes and other large storms on ecological communities and the post-event recovery in these communities can guide management and ecosystem restoration. This is particularly important for communities impacted by invasive species, as the hurricane may affect control efforts. Here we consider the effect of a hurricane...
Caribou use of habitat near energy development in Arctic Alaska
Heather E. Johnson, Trevor Golden, Layne G. Adams, David Gustine, Elizabeth A. Lenart
2020, Journal of Wildlife Management (84) 401-412
Increasing demands for energy have generated interest in expanding oil and gas production on the North Slope of Alaska, raising questions about the resilience of barren-ground caribou populations to new development. Although the amount of habitat lost directly to energy development in the Arctic will likely be relatively small, there...
An assessment of the representation of ecosystems in global protected areas using new maps of World Climate Regions and World Ecosystems
Roger Sayre, Deniz Karagulle, Charlie Frye, Timothy Boucher, Nicholas Wolff, Sean Breyer, Dawn Wright, Madeline T. Martin, Kevin Butler, Keith Van Graafeiland, Jerry Touval, Leonardo Sotomayor, Jennifer McGowan, Edward T. Game, Hugh P. Possingham
2020, Global Ecology and Conservation (21)
Representation of ecosystems in protected area networks and conservation strategies is a core principle of global conservation priority setting approaches and a commitment in Aichi Target 11 of the Convention on Biological Diversity. The 2030 Sustainable Development Goals (SDGs) explicitly call for the conservation of terrestrial, freshwater, and marine ecosystems....
Testing reproducibility of vitrinite and solid bitumen reflectance measurements in North American unconventional source-rock reservoir petroleum systems
Paul C. Hackley, Carla V. Araujo, Angeles G. Borrego, Antonis Bouzinos, Brian J. Cardott, H. Carvajal-Ortiz, Martha Rocio Lopez Cely, Vongani Chabalala, Peter J. Crosdale, Thomas D. Demchuk, Cortland F. Eble, Deolinda Flores, Agnieszka Furmann, Thomas Gentzis, Paula Goncalves, Carsten Guvad, M. Hamor-Vido, Iwona Jelonek, M. Johnston, Tatiana Juliao-Lemus, Stavros Kalaitzidis, Wayne Knowles, Jolanta Kus, Zhongsheng Li, Gordon Macleod, Maria Mastalerz, Taissa Rego Menezes, Seare Ocubalidet, Richard Orban, Walter Pickel, Paddy Ranasinghe, Joana Ribeiro, Olga Patricia Gomez Rojas, Ricardo Ruiz-Monroy, Jaques Schmidt, Abbas Seyedolali, Georgios Siavalas, Isabel Suarez-Ruiz, Carlos Vargas Vargas, Brett J. Valentine, Nicola Wagner, Bree Wrolson, Julian Esteban Jaramillo Zapata
2020, Marine and Petroleum Geology (114)
An interlaboratory study (ILS) was conducted to test reproducibility of vitrinite and solid bitumen reflectance measurements in six mudrock samples from United States unconventional source-rock reservoir petroleum systems. Samples selected from the Marcellus, Haynesville, Eagle Ford, Barnett, Bakken and Woodford are...
Traversing the wasteland: A framework for assessing ecological threats to drylands
David L. Hoover, Brandon T. Bestelmeyer, Nancy B. Grimm, Travis E. Huxman, Sasha C. Reed, Osvaldo E. Sala, Timothy Seastedt, Hailey Wilmer, Scott Ferrenberg
2020, BioScience (70) 35-47
Drylands cover 41% of the Earth's terrestrial surface, play a critical role in global ecosystem function, and are home to over two billion people. Like other biomes, drylands face increasing pressure from global change, but many of these ecosystems are close to tipping points, which, if crossed, can lead...
Rapid early development and feeding benefits an invasive population of lake trout
Lee G. Simard, J Ellen Marsden, Robert E. Gresswell, Megan Euclide
2020, Canadian Journal of Fisheries and Aquatic Sciences (77) 496-504
Lake trout (Salvelinus namaycush) were discovered in Yellowstone Lake in 1994 and their population expanded dramatically despite intensive suppression. The lake is species-depauperate, with no major lake trout embryo predators. We hypothesized that without this predation threat, lake trout free embryo feeding and growth may be greater than in their...
Fault fictions: Systematic biases in the conceptualization of fault-zone architecture
Zoe K Shipton, Jennifer J Roberts, Comrie Emma L, Yannick Kremer, Rebecca J Lunn, Jonathan Saul Caine
2020, Special Publications (496) 125-143
Mental models are a human's internal representation of the real world and have an important role in the way we understand and reason about uncertainties, explore potential options and make decisions. Mental models have not yet received much attention in geosciences, yet systematic biases can affect...
UAV-derived estimates of forest structure to inform ponderosa pine forest restoration
Adam Belmonte, Temuulen T. Sankey, Joel A. Biederman, John B. Bradford, Scott J. Goetz, Thomas Kolb, Travis Woolley
2020, Remote Sensing in Ecology and Conservation (6) 181-197
Restoring forest ecosystems has become an increasingly high priority for land managers across the American West. Millions of hectares of forest are in need of drastic yet strategic reductions in density (e.g., basal area). Meeting the restoration and management goals requires quantifying metrics of vertical and horizontal forest structure, which...
Time scales of arsenic variability and the role of high-frequency monitoring at three water-supply wells in New Hampshire, USA
James R. Degnan, Joseph P. Levitt, Melinda Erickson, Bryant C. Jurgens, Bruce D. Lindsey, Joseph D. Ayotte
2020, Science of the Total Environment (709)
Groundwater geochemistry, redox process classification, high-frequency physicochemical and hydrologic measurements, and climate data were analyzed to identify controls on arsenic (As) concentration changes. Groundwater was monitored in two public-supply wells (one glacial aquifer and one bedrock aquifer), and one bedrock-aquifer domestic well in New...
The assessment and remediation of mercury contaminated sites: A review of current approaches
Chris S. Eckley, Cynthia C Gilmour, Sarah E. Janssen, Todd P Luxton, Paul M Randall, Lindsay Whalin, Carrie Austin
2020, Science of the Total Environment (707)
Remediation of mercury (Hg) contaminated sites has long relied on traditional approaches, such as removal and containment/capping. Here we review contemporary practices in the assessment and remediation of industrial-scale Hg contaminated sites and discuss recent advances. Significant improvements have been made in site assessment, including the use of XRF to...
Seismo-acoustic evidence for vent drying during shallow submarine eruptions at Bogoslof volcano, Alaska
David Fee, John J. Lyons, Matthew M. Haney, Aaron Wech, Christopher F. Waythomas, Angela K. Diefenbach, Taryn Lopez, Alexa R. Van Eaton, David J. Schneider
2020, Bulletin of Volcanology Special Issue on the Bogoslof Eruption (82)
Characterizing the state of the volcanic vent is key for interpreting observational datasets and accurately assessing volcanic hazards. This is particularly true for remote, complex eruptions such as the 2016–2017 Bogoslof volcano, Alaska eruption sequence. Bogoslof’s eruptions in this period were either shallow submarine or subaerial, or some combination of...
Traveling to thermal refuges during stressful temperatures leads to foraging constraints in a central-place forager
Catherine G. Haase, Robert J. Fletcher Jr., Daniel H. Slone, James P. Reid, Susan M. Butler
2020, Journal of Mammalogy (101) 271-280
Central-place foragers can be constrained by the distance between habitats. When an organism relies on a central place for thermal refuge, the distance to food resources can potentially constrain foraging behavior. We investigated the effect of distance between thermal refuges and forage patches of the cold-intolerant marine mammal, the Florida...
Species traits predict stream-fish invaders in an Appalachian (U.S.A.) river basin
Joseph D. Buckwalter, Emmanuel A Frimpong, Paul L. Angermeier, Jacob N. Barney
2020, Freshwater Biology (65) 552-564
We compared the influence of biological traits (morphology, physiology, reproduction, and life history), ecological traits (geographic distribution, habitat associations, food habits), and introduction attributes (propagule pressure, human use of a species, residence time) on invasion success of native and introduced stream fishes during the colonisation and spread stages in...
Not all fuel‐reduction treatments degrade biocrusts: Herbicides cause mostly neutral to positive effects on cover of biocrusts
Lea A. Condon, Margaret L Gray
2020, Land Degradation & Development (31) 1727-1734
In response to increasing fire, fuel‐reduction treatments are being used to minimize large fire risk. Although biocrusts are associated with reduced cover of fire‐promoting, invasive grasses, the impact of fuel‐reduction treatments on biocrusts is poorly understood. We use data from a long‐term experiment, the Sagebrush Steppe Treatment Evaluation Project, testing...
A comparison of the Trojan Y Chromosome strategy to harvesting models for eradication of nonnative species
Jingjing Lyu, Pamela J. Schofield, Kristen Reaver, Matthew Beauregard, Rana D. Parshad
2020, Natural Resource Modeling (33)
The Trojan Y Chromosome strategy (TYC) is a promising eradication method for biological control of nonnative species. The strategy works by manipulating the sex ratio of a population through the introduction of supermales that guarantee male offspring. In the current study, we compare the TYC method with a pure harvesting strategy. We...
Chronic and episodic acidification of streams along the Appalachian Trail corridor, eastern United States
Douglas A. Burns, Todd McDonnell, Karen C. Rice, Gregory B. Lawrence, Timothy Sullivan
2020, Hydrological Processes (34) 1498-1513
Acidic atmospheric deposition has adversely affected aquatic ecosystems globally. As emissions and deposition of sulfur (S) and nitrogen (N) have declined in recent decades across North America and Europe, ecosystem recovery is evident in many surface waters. However, persistent chronic and episodic acidification remain important concerns in vulnerable regions. We...
