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Page 1013, results 25301 - 25325

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Decadal shifts in grass and woody plant cover are driven by prolonged drying and modified by topo‐edaphic properties
Seth M. Munson, Temuulen T. Sankey, George Z. Xian, Miguel L. Villarreal, Collin G. Homer
2016, Ecological Applications (26) 2480-2494
Woody plant encroachment and overall declines in perennial vegetation in dryland regions can alter ecosystem properties and indicate land degradation, but the causes of these shifts remain controversial. Determining how changes in the abundance and distribution of grass and woody plants are influenced by conditions that regulate water availability at...
Mineralogy, chemistry, and fluid-aided evolution of the Pea Ridge Fe oxide-(Y + REE) deposit, southeast Missouri, USA
Daniel E. Harlov, Corey J. Meighan, Ian D. Kerr, Iain M. Samson
2016, Economic Geology (111) 1963-1984
The Kiruna-type Pea Ridge iron oxide-apatite (IOA) deposit is hosted by a sequence of 1.47 Ga rhyolite tuffs of the St. Francois Mountains, southeast Missouri, USA. It consists of a series of altered zones composed mainly of amphibole, magnetite, hematite, and quartz, together with the presence of several rare earth...
Mineral thermometry and fluid inclusion studies of the Pea Ridge iron oxide-apatite–rare earth element deposit, Mesoproterozoic St. Francois Mountains Terrane, southeast Missouri, USA
Albert H. Hofstra, Corey J. Meighan, Xinyu Song, Iain Samson, Erin E. Marsh, Heather A. Lowers, Poul Emsbo, Andrew G. Hunt
2016, Economic Geology (111) 1985-2016
Mineral thermometry and fluid inclusion studies were conducted on variably altered and mineralized samples from the Mesoproterozoic Pea Ridge iron oxide-apatite (IOA)-rare earth element (REE) deposit in order to constrain P-T conditions, fluid chemistry, and the source of salt and volatiles during early magnetite and later REE mineralization.Scanning electron microscopy...
Changes in pond water levels and surface extent due to climate variability alter solute sources to closed-basin Prairie-Pothole wetland ponds, 1979 to 2012
James W. LaBaugh, David M. Mushet, Donald O. Rosenberry, Ned H. Euliss Jr., Martin B. Goldhaber, Christopher T. Mills, Richard D. Nelson
2016, Wetlands (36) 343-355
Wetter conditions beginning in 1993 resulted in marked changes in water levels and surface extent of prairie-pothole region wetland ponds, including closed-basin wetlands in the Cottonwood Lake area of North Dakota, U.S.A. Pond water levels after 1993 were consistently 0.5 to 2 m higher than during 1979–1993 (≤ 1 m deep) in...
Bitumen prices and structural changes in North American crude oil markets
Emil D. Attanasi
2016, Natural Resources Research (25) 487-496
In an earlier report, changes in bitumen prices at Hardesty, Alberta, Canada, were modeled as the responses to changes in monthly prices of Hardesty light/medium crude oil for the period 2000–2006 with a simple error correction econometric model. This note re-examines that price relationship for the period 2009–2014. Over the...
Katmai National Park and Preserve and Alagnak Wild River: Geologic resources inventory report
Chad Hults, Judith E. Fierstein
2016, Natural Resource Report NPS/NRSS/GRD/NRR—2016/1314
The Geologic Resources Inventory (GRI) is one of 12 inventories funded by the National Park Service (NPS) Inventory and Monitoring Program. The Geologic Resources Division of the NPS Natural Resource Stewardship and Science Directorate administers the GRI. This GRI report was written for resource managers to support science-informed decision making....
Shifting patterns in SAV species diversity and community structure
Nancy B. Rybicki, Christopher E. Tanner, Erin C. Shields, Kenneth A. Moore, Stanley Kollar, David J. Wilcox, Katherina A. M. Engelhardt
2016, Book chapter, Chesapeake Bay submerged aquatic vegetation (SAV): A third technical synthesis
This chapter examines the shifting patterns in Chesapeake SAV community structure and the potential environmental variables that explain variation in species composition patterns at both long and short time periods. Bay-wide species occurrence data sets are summarized. These data show that twenty-seven or more species of SAV are found within...
Re-Occupancy of Breeding Territories by Ferruginous Hawks in Wyoming: Relationships to Environmental and Anthropogenic Factors
Zachary P. Wallace, Patricia L. Kennedy, John R. Squires, Robert J. Oakleaf, Lucretia E. Olson, Katie M. Dugger
2016, PLoS ONE (11)
Grassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by non-anthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models. We used design-based sampling and occupancy models to test relationships of environmental...
The relative contributions of disease and insects in the decline of a long-lived tree: a stochastic demographic model of whitebark pine (Pinus albicaulis)
Erik S Jules, Jenell I. Jackson, Phillip J. van Mantgem, Jennifer S. Beck, Michael P. Murray, E. April Sahara
2016, Forest Ecology and Management (381) 144-156
Pathogens and insect pests have become increasingly important drivers of tree mortality in forested ecosystems. Unfortunately, understanding the relative contributions of multiple mortality agents to the population decline of trees is difficult, because it requires frequent measures of tree survival, growth, and recruitment, as well as the incidence of mortality...
Population-specific life histories contribute to metapopulation viability
Samniqueka J. Halsey, Timothy J. Bell, Kathryn McEachern, Noel B. Pavlovic
2016, Ecosphere (7) 1-13
Restoration efforts can be improved by understanding how variations in life-history traits occur within populations of the same species living in different environments. This can be done by first understanding the demographic responses of natural occurring populations. Population viability analysis continues to be useful to species management and conservation with...
Indications of a positive feedback between coastal development and beach nourishment
Scott Armstrong, Eli D. Lazarus, Patrick W. Limber, Evan B. Goldstein, Curtis Thorpe, Rhoda Ballinger
2016, Earth's Future (4) 626-635
Beach nourishment, a method for mitigating coastal storm damage or chronic erosion by deliberately replacing sand on an eroded beach, has been the leading form of coastal protection in the U.S. for four decades. However, investment in hazard protection can have the unintended consequence of encouraging development in places especially...
Summary of SPT based field case history data of CETIN (2016) database
K. Onder Cetin, Raymond B. Seed, Robert E. Kayen, Robb E. S. Moss, H. Tolga Bilge, Makbule Ilgac, Khaled Chowdhury
2016, Report
This report provides documentation of the Cetin et al. (2016) field performance case histories, probabilistic maximum likelihood assessment and the sources of differences between the liquefaction triggering resistance estimations (CRR values) of the widely used liquefaction triggering relationships of Seed et al. (1985), Cetin et al. (2004, 2016) and Boulanger...
Topographic and fire weather controls of fire refugia in forested ecosystems of northwestern North America
Meg A. Krawchuk, Sandra L. Haire, Jonathan D. Coop, Marc-André Parisien, Ellen Whitman, Geneva W. Chong, Carol Miller
2016, Ecosphere (7) 1-18
Fire refugia, sometimes referred to as fire islands, shadows, skips, residuals, or fire remnants, are an important element of the burn mosaic, but we lack a quantitative framework that links observations of fire refugia from different environmental contexts. Here, we develop and test a conceptual model for how predictability of...
Evaluating early-warning indicators of critical transitions in natural aquatic ecosystems
Alena Sonia Gsell, Ulrike Scharfenberger, Deniz Ozkundakci, Annika W. Walters, Lars-Anders Hansson, Annette B. G. Janssen, Peeter Noges, Philip Reid, Daniel Schindler, Ellen van Donk, Vasilis Dakos, Rita Adrian
2016, Proceedings of the National Academy of Sciences of the United States of America (113) E8089-E8095
Ecosystems can show sudden and persistent changes in state despite only incremental changes in drivers. Such critical transitions are difficult to predict, because the state of the system often shows little change before the transition. Early-warning indicators (EWIs) are hypothesized to signal the loss of system resilience and have been...
Using resilience and resistance concepts to manage threats to sagebrush ecosystems, Gunnison sage-grouse, and Greater sage-grouse in their eastern range: A strategic multi-scale approach
Jeanne C. Chambers, Jeffrey L. Beck, Steve Campbell, John Carlson, Thomas J. Christiansen, Karen J. Clause, Jonathan B. Dinkins, Kevin E. Doherty, Kathleen A. Griffin, Douglas W. Havlina, Kenneth F. Mayer, Jacob D. Hennig, Laurie L. Kurth, Jeremy D. Maestas, Mary E. Manning, Brian A. Mealor, Clinton McCarthy, Marco A. Perea, David A. Pyke
2016, General Technical Report RMRS-GTR-356
This report provides a strategic approach developed by a Western Association of Fish and Wildlife Agencies interagency working group for conservation of sagebrush ecosystems, Greater sage-grouse, and Gunnison sage-grouse. It uses information on (1) factors that influence sagebrush ecosystem resilience to disturbance and resistance to nonnative invasive annual grasses and...
Does paleoseismology forecast the historic rates of large earthquakes on the San Andreas fault system?
Glenn Biasi, Katherine M. Scharer, Ray J. Weldon, Timothy E. Dawson
2016, Conference Paper, Proceedings of the 7th PATA Days, 2016
The 98-year open interval since the most recent ground-rupturing earthquake in the greater San Andreas boundary fault system would not be predicted by the quasi-periodic recurrence statistics from paleoseismic data. We examine whether the current hiatus could be explained by uncertainties in earthquake dating. Using seven independent paleoseismic records,...
Perspectives on bay-delta science and policy
Michael Healey, Michael D. Dettinger, Richard Norgaard
2016, San Francisco Estuary and Watershed Science (14) 1-25
The State of Bay–Delta Science 2008 highlighted seven emerging perspectives on science and management of the Delta. These perspectives had important effects on policy and legislation concerning management of the Delta ecosystem and water exports. From the collection of papers that make up the State of Bay–Delta Science 2016, we...
The 2016 groundwater flow model for Dane County, Wisconsin
Michael J. Parsen, Kenneth R. Bradbury, Randall J. Hunt, Daniel T. Feinstein
2016, Bulletin 110
A new groundwater flow model for Dane County, Wisconsin, replaces an earlier model developed in the 1990s by the Wisconsin Geological and Natural History Survey (WGNHS) and the U.S. Geological Survey (USGS). This modeling study was conducted cooperatively by the WGNHS and the USGS with funding from the Capital Area...
Using large-scale flow experiments to rehabilitate Colorado River ecosystem function in Grand Canyon: Basis for an adaptive climate-resilient strategy
Theodore S. Melis, William E. Pine III, Josh Korman, Michael D. Yard, Shaleen Jain, Roger S. Pulwarty
Kathleen Miller, Alan F. Hamlet, Douglas S. Kenney, Kelly T. Redmond, editor(s)
2016, Book chapter, Water policy and planning in a variable and changing climate
Adaptive management of Glen Canyon Dam is improving downstream resources of the Colorado River in Glen Canyon National Recreation Area and Grand Canyon National Park. The Glen Canyon Dam Adaptive Management Program (AMP), a federal advisory committee of 25 members with diverse special interests tasked to advise the U.S. Department...
Interagency Pacific marten (Martes caurina) distribution study on the Olympic Peninsula, Washington
Katie Moriarty, Betsy Howell, Connor Morozumi, Patti Happe, Kurt J. Jenkins, Keith B. Aubry
2016, Report
The objective of this study was to determine if the Pacific marten (Martes caurina) still occurs on the Olympic Peninsula in Washington State. We reviewed recent records of marten observations on the Olympic Peninsula since 1998, and conducted new surveys in undersampled regions of the Olympic Peninsula during...
Population demographics for the federally endangered dwarf wedgemussel
Heather S. Galbraith, William A. Lellis, Jeffrey C. Cole, Carrie J. Blakeslee, Barbara St. John White
2016, Journal of Fish and Wildlife Management (7) 377-387
The dwarf wedgemussel, Alasmidonta heterodon, is a federally endangered freshwater mussel species inhabiting several Atlantic Slope rivers. Studies on population demographics of this species are necessary for status assessment and directing recovery efforts. We conducted qualitative and quantitative surveys for dwarf wedgemussel in the mainstem Delaware River and in four...
Clinal patterns in genetic variation for northern leopard frog (Rana pipiens): Conservation status and population histories
Craig A. Stockwell, Justin D.L. Fisher, Kyle I. McLean
2016, Wetlands (36) 437-443
The security of the northern leopard frog (Rana pipiens) varies spatially with populations east and west of North Dakota considered as secure and at risk, respectively. We used genetic markers to characterize the conservation status of northern leopard frog populations across North Dakota. We used multiple regression analyses...
Testing geomorphology-derived rupture histories against the paleoseismic record of the southern San Andreas fault
Katherine M. Scharer, Ray J. Weldon, Sean Bemis
2016, Conference Paper, Proceedings of the 7th PATA Days, 2016
Evidence for the 340-km-long Fort Tejon earthquake of 1857 is found at each of the high-resolution paleoseismic sites on the southern San Andreas Fault. Using trenching data from these sites, we find that the assemblage of dated paleoearthquakes recurs quasi-periodically (coefficient of variation, COV, of 0.6, Biasi, 2013) and requires...