Publications
Filter Total Items: 1336
Root-driven weathering impacts on mineral-organic associations in deep soils over pedogenic time scales
Plant roots are critical weathering agents in deep soils, yet the impact of resulting mineral transformations on the vast deep soil carbon (C) reservoir are largely unknown. Root-driven weathering of primary minerals may cause the formation of reactive secondary minerals, which protect mineral-organic associations (MOAs) for centuries or millennia. Conversely, root-driven weathering may also trans
Authors
Mariela Garcia Arredondo, Corey Lawrence, Marjorie S. Schulz, Malak M. Tfaily, Ravi K. Kukkadapu, Morris E. Jones, Kristin Boye, Marco Keiluweit
Geographic context affects the landscape change and fragmentation caused by wind energy facilities
Wind energy generation causes transformation of landscapes as new roads, pads, and transmission lines are constructed. Limiting the landscape change and fragmentation caused by these facilities likely minimizes impacts to biodiversity and sensitive wildlife species. We examined the effects of wind energy facilities’ geographic context on changes in landscape patterns. We digitized the footprints o
Authors
James E. Diffendorfer, Monica Dorning, Jolene Keen, Louisa Kramer, Robert Taylor
Influences of potential oil and gas development and future climate on Sage-grouse declines and redistribution
Multiple environmental stressors impact wildlife populations, but we often know little about their cumulative and combined influences on population outcomes. We generally know more about past effects than potential future impacts, and direct influences such as changes of habitat footprints than indirect, long-term responses in behavior, distribution, or abundance. Yet, an understanding of all thes
Authors
Julie A. Heinrichs, Michael S. O'Donnell, Cameron L. Aldridge, Steven L. Garman, Collin G. Homer
Modeling transient soil moisture limitations on microbial carbon respiration: A cost-performance comparison
Soil microorganisms are known to survive periods of aridity and to recover rapidly after wetting events, with the ability to transition between a dormant state in dry conditions and an active state in wet conditions. Though this dynamic behavior has been previously incorporated into soil carbon respiration modeling frameworks, a direct comparison between this active-dormant transition mechanism an
Authors
Yuchen Liu, Corey R. Lawrence, Mathew Winnick, Hsiao-Tieh Hsu, Katherine Maher, Jennifer Druhan
The antiquity of the Sahara Desert: New evidence from the mineralogy and geochemistry of Pliocene paleosols on the Canary Islands, Spain
The Sahara is the largest warm desert in the world, but its age has been controversial, with estimates ranging from Miocene to Holocene. Mineralogical and geochemical data show that paleosols of Pliocene to mid-Pleistocene age on Fuerteventura and Gran Canaria in the Canary Islands have developed in part from inputs of dust from Africa. These paleosols contain quartz and mica, minerals that are ab
Authors
Daniel R. Muhs, Joaquin Meco, James R. Budahn, Gary L. Skipp, Juan F. Betancort, Alejandro Lomoschitz
Principles and history of luminescence dating
No abstract available.
Authors
Shannon A. Mahan, Regina DeWitt
Late Quaternary paleohydrology of desert wetlands and pluvial lakes in the Soda Lake basin, central Mojave Desert, California (USA)
Sediment cores taken near extant springs along the western margin of Soda Lake playa, as well as from the playa center, reveal dramatic hydrologic changes that occurred in the central Mojave Desert during the late Quaternary. Results of stratigraphic, chronologic, physical, chemical, and microfossil analyses of seven cores, ranging in length from 5 to 23 m, help refine the timing and character of
Authors
Jeffrey S. Honke, Jeffrey S. Pigati, J. Wilson, J. Bright, H.L. Goldstein, Gary L. Skipp, M. C. Reheis, J. C. Havens
Petrology of volcanic rocks associated with silver-gold (Ag-Au) epithermal deposits in the Tonopah, Divide, and Goldfield Mining Districts, Nevada
Miocene calc-alkaline volcanic rocks, part of the southern segment of the ancestral Cascades magmatic arc, are spatially, temporally, and likely genetically associated with precious metal epithermal deposits in the Tonopah, Divide, and Goldfield Districts of west-central Nevada. In the Tonopah mining district, volcanic rocks include the Mizpah Trachyte, Fraction Tuff, and Oddie Rhyolite; in the Di
Authors
Edward A. du Bray, David John, Joseph Colgan, Peter G. Vikre, Michael A. Cosca, Leah E. Morgan
Late Quaternary vegetation development following deglaciation of northwestern Alexander Archipelago, Alaska
The Cordilleran Ice sheet covered most of southeastern Alaska during the Last Glacial Interval (LGI: Marine Isotope Stage 2). Ice began to recede from western Alexander Archipelago ~17,000 + 700 yr BP. In this study pollen analysis and radiocarbon dating of three sediment cores were used to reconstruct, for the first time, the postglacial development of vegetation of the northwestern Alexander Ar
Authors
Thomas A. Ager
Using a GIS to populate 3D geocellular geologic models
No abstract available
Authors
Donald S. Sweetkind, Geoffrey Cromwell
Guidance for assessing interregional ecoystem service flows
Ecosystem services (ES) assessments commonly focus on a specific biophysical region or nation and take its geographic borders as the system boundary. Most geographical regions are, however, not closed systems but are open and telecoupled with other regions through ES imports and exports, which are mediated by fluxes of matter, energy and information. Interregional ES flows are often linked to nati
Authors
Thomas Koellner, Aletta Bonn, Sebastian Arnhold, Kenneth J. Bagstad, Dor Friedman, Carlos Guerra, Thomas Kastner, Meidad Kissinger, Janina Kleeman, Christian Kuhlicke, Jianguo Liu, Laura Lopez-Hoffman, Alexandra Marques, Berta Martin-Lopez, Catharina J. E. Schulp, Sarah Wolff, Matthias Schröter
Petrographic, geochemical, and geochronologic data for cenozoic volcanic rocks of the Tonopah, Divide, and Goldfield Mining Districts, Nevada
The purpose of this report is to summarize geochemical, petrographic, and geochronologic data for samples, principally those of unmineralized Tertiary volcanic rocks, from the Tonopah, Divide, and Goldfield mining districts of west-central Nevada (fig. 1). Much of the data presented here for the Tonopah and Divide districts are for samples collected by Bonham and Garside (1979) during geologic map
Authors
Edward A. du Bray, David John, Peter G. Vikre, Joseph Colgan, Michael A. Cosca, Leah E. Morgan, Robert J. Fleck, Wayne R. Premo, Christopher S. Holm-Denoma