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Publications

Filter Total Items: 234

Quasi-extinction risk and population targets for the Eastern, migratory population of monarch butterflies (Danaus plexippus) Quasi-extinction risk and population targets for the Eastern, migratory population of monarch butterflies (Danaus plexippus)

The Eastern, migratory population of monarch butterflies (Danaus plexippus), an iconic North American insect, has declined by ~80% over the last decade. The monarch’s multi-generational migration between overwintering grounds in central Mexico and the summer breeding grounds in the northern U.S. and southern Canada is celebrated in all three countries and creates shared management...
Authors
Brice X. Semmens, Darius J. Semmens, Wayne E. Thogmartin, Ruscena Wiederholt, Laura Lopez-Hoffman, James E. Diffendorfer, John M. Pleasants, Karen S. Oberhauser, Orley R. Taylor

Hydrologic indicators of hot spots and hot moments of mercury methylation potential along river corridors Hydrologic indicators of hot spots and hot moments of mercury methylation potential along river corridors

The biogeochemical cycling of metals and other contaminants in river-floodplain corridors is controlled by microbial activity responding to dynamic redox conditions. Riverine flooding thus has the potential to affect speciation of redox-sensitive metals such as mercury (Hg). Therefore, inundation history over a period of decades potentially holds information on past production of...
Authors
Michael B. Singer, Lee R. Harrison, Patrick M. Donovan, Joel D. Blum, Mark C. Marvin-DiPasquale

Surface-air mercury fluxes across Western North America: A synthesis of spatial trends and controlling variables Surface-air mercury fluxes across Western North America: A synthesis of spatial trends and controlling variables

Mercury (Hg) emission and deposition can occur to and from soils, and are an important component of the global atmospheric Hg budget. This paper focuses on synthesizing existing surface-air Hg flux data collected throughout the Western North American region and is part of a series of geographically focused Hg synthesis projects. A database of existing Hg flux data collected using the...
Authors
Chris S. Eckley, Michael Tate, Che-Jen Lin, Mae S. Gustin, Stephen Dent, Collin Eagles-Smith, Michelle A. Lutz, Kimberly Wickland, Bronwen Wang, John E. Gray, Grant Edwards, David P. Krabbenhoft, David B. Smith

An alternative framework for responding to the amphibian crisis An alternative framework for responding to the amphibian crisis

Volumes of data illustrate the severity of the crisis affecting amphibians, where > 32% of amphibians worldwide are threatened with declining populations. Although there have been isolated victories, the current approach to the issue is unsuccessful. We suggest that a radically different approach, something akin to human emergency response management (i.e. the Incident Command System)...
Authors
Erin L. Muths, Robert N. Fisher

Deserts Deserts

The deserts of California (Lead photo, Fig. 1) occupy approximately 38% of California’s landscape (Table 1) and consist of three distinct deserts: the Great Basin Desert, Mojave Desert, and Colorado Desert, the latter of which is a subdivision of the Sonoran Desert (Brown and Lowe 1980). The wide range of climates and geology found within each of these deserts result in very different...
Authors
Jayne Belnap, Robert H. Webb, Todd Esque, Matthew L. Brooks, Lesley A. DeFalco, James A. MacMahon

Implications of projected climate change for groundwater recharge in the western United States Implications of projected climate change for groundwater recharge in the western United States

Existing studies on the impacts of climate change on groundwater recharge are either global or basin/location-specific. The global studies lack the specificity to inform decision making, while the local studies do little to clarify potential changes over large regions (major river basins, states, or groups of states), a scale often important in the development of water policy. An...
Authors
Thomas Meixner, Andrew H. Manning, David A. Stonestrom, Diana M. Allen, Hoori Ajami, Kyle W. Blasch, Andrea E. Brookfield, Christopher L. Castro, Jordan F. Clark, David Gochis, Alan L. Flint, Kirstin L. Neff, Rewati Niraula, Matthew Rodell, Bridget R. Scanlon, Kamini Singha, Michelle Ann Walvoord

Crustal permeability Crustal permeability

Permeability is the primary control on fluid flow in the Earth’s crust and is key to a surprisingly wide range of geological processes, because it controls the advection of heat and solutes and the generation of anomalous pore pressures. The practical importance of permeability – and the potential for large, dynamic changes in permeability – is highlighted by ongoing issues associated...

Accelerating advances in continental domain hydrologic modeling Accelerating advances in continental domain hydrologic modeling

In the past, hydrologic modeling of surface water resources has mainly focused on simulating the hydrologic cycle at local to regional catchment modeling domains. There now exists a level of maturity among the catchment, global water security, and land surface modeling communities such that these communities are converging toward continental domain hydrologic models. This commentary...
Authors
Stacey A. Archfield, Martyn Clark, Berit Arheimer, Lauren E. Hay, Hilary McMillan, Julie E. Kiang, Jan Seibert, Kirsti Hakala, Andrew R. Bock, Thorsten Wagener, William H. Farmer, Vazken Andreassian, Sabine Attinger, Alberto Viglione, Rodney Knight, Steven L. Markstrom, Thomas M. Over

Seismic hazard assessment: Honing the debate, testing the models Seismic hazard assessment: Honing the debate, testing the models

Four workshops held in 2013–2014 at the U.S. Geological Survey (USGS) John Wesley Powell Center for Analysis and Synthesis brought together university, government, and insurance industry scientists from countries that straddle plate boundaries and those in plate interiors. Participants were invited; the workshops’ goals involved developing tests of Probabilistic Seismic Hazard Analysis...
Authors
Ross Stein, Mark W. Stirling

Powell Center Newsletter, Volume 2, Issue 1 Powell Center Newsletter, Volume 2, Issue 1

Bi-annual newsletter for the John Wesley Powell Center for Analysis and Synthesis, covering news through July of 2015
Authors
Jill S. Baron, Marty Goldhaber

Linking microbial community structure and microbial processes: An empirical and conceptual overview Linking microbial community structure and microbial processes: An empirical and conceptual overview

A major goal of microbial ecology is to identify links between microbial community structure and microbial processes. Although this objective seems straightforward, there are conceptual and methodological challenges to designing studies that explicitly evaluate this link. Here, we analyzed literature documenting structure and process responses to manipulations to determine the frequency...
Authors
R.L. Bier, Emily S. Bernhardt, Claudia M. Boot, Emily B. Graham, Edward K. Hall, Jay T. Lennon, Diana R. Nemergut, Brooke B. Osborne, Clara Ruiz-Gonzalez, Joshua P. Schimel, Mark P. Waldrop, Matthew D. Wallenstein

Multiscale analysis of river networks using the R package linbin Multiscale analysis of river networks using the R package linbin

Analytical tools are needed in riverine science and management to bridge the gap between GIS and statistical packages that were not designed for the directional and dendritic structure of streams. We introduce linbin, an R package developed for the analysis of riverscapes at multiple scales. With this software, riverine data on aquatic habitat and species distribution can be scaled and...
Authors
Ethan Z. Welty, Christian E. Torgersen, Samuel J. Brenkman, Jeffrey J. Duda, Jonathan B. Armstrong
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