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Full-Text Articles in Other Earth Sciences

Loess Deposits, Origins And Properties, Daniel R. Muhs Jan 2007

Loess Deposits, Origins And Properties, Daniel R. Muhs

United States Geological Survey: Staff Publications

Loess is an eolian (windblown) sediment that is an important archive of Quaternary climate changes. It may provide one of the most complete terrestrial records of interglacial–glacial cycles. Loess is unusual as a record of Quaternary climate change because it is one of the few sediments that is deposited directly from the atmosphere. Thus, it is a geologic deposit that contains a record of atmospheric circulation and can be used to reconstruct synoptic-scale paleoclimatology. Loess is also unusual in that it can be dated directly using ‘trapped electron’ or luminescence methods that require only the sediment itself. Commonly, loess deposits …


Enhancing The Detection And Classification Of Coral Reef And Associated Benthic Habitats: A Hyperspectral Remote Sensing Approach, Deepak R. Mishra, Sunil Narumalani, Donald Rundquist, Merlin P. Lawson, R. Perk Jan 2007

Enhancing The Detection And Classification Of Coral Reef And Associated Benthic Habitats: A Hyperspectral Remote Sensing Approach, Deepak R. Mishra, Sunil Narumalani, Donald Rundquist, Merlin P. Lawson, R. Perk

Center for Advanced Land Management Information Technologies: Publications

Coral reefs and associated benthic habitats are heterogeneous in nature. A remote sensor designed to discriminate these environments requires a high number of narrow, properly placed bands which are not currently available in existing satellite sensors. Optical hyperspectral sensors mounted on aerial platforms seem to be appropriate for overcoming the lack of both high spectral and spatial resolution of satellite sensors. This research presents results of an innovative coral reef application by such a sensor. Using hyperspectral Airborne Imaging Spectroradiometer for Applications (AISA) Eagle data, the approach presented solves the confounding influence of water column attenuation on substrate reflectance on …


Adaptive Data-Driven Models For Estimating Carbon Fluxes In The Northern Great Plains, Bruce K. Wylie, Eugene A. Fosnight, Tagir G. Gilmanov, Albert B. Frank, Jack A. Morgan, Marshall R. Haferkamp, Tilden P. Meyers Jan 2007

Adaptive Data-Driven Models For Estimating Carbon Fluxes In The Northern Great Plains, Bruce K. Wylie, Eugene A. Fosnight, Tagir G. Gilmanov, Albert B. Frank, Jack A. Morgan, Marshall R. Haferkamp, Tilden P. Meyers

United States Geological Survey: Staff Publications

Rangeland carbon fluxes are highly variable in both space and time. Given the expansive areas of rangelands, how rangelands respond to climatic variation, management, and soil potential is important to understanding carbon dynamics. Rangeland carbon fluxes associated with Net Ecosystem Exchange (NEE) were measured from multiple year data sets at five flux tower locations in the Northern Great Plains. These flux tower measurements were combined with 1-km2 spatial data sets of Photosynthetically Active Radiation (PAR), Normalized Difference Vegetation Index (NDVI), temperature, precipitation, seasonal NDVI metrics, and soil characteristics. Flux tower measurements were used to train and select variables for …


Droughtscape, Winter 2007, Kelly Smith Jan 2007

Droughtscape, Winter 2007, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

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Policy Update: NIDIS is Law. What’s Next?

What Would You Like to See?

TX, OK, Plains, Southwest Hardest Hit in 2006

Climatologically Speaking, How Bad Was It?

State Spotlight: Arizona

Drought Decision-Support Tools Evolving


Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May Jan 2007

Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May

United States Geological Survey: Publications

This report summarizes the findings of a study conducted as a pilot for part of a park-wide monitoring program being developed for the Ozark National Scenic Riverways (ONSR) of southeastern Missouri. The objective was to evaluate using crayfish (Orconectes spp.) and Asian clam (Corbicula fluminea) for monitoring concentrations of metals associated with lead-zinc mining. Lead-zinc mining presently (2007) occurs near the ONSR and additional mining has been proposed. Three composite samples of each type (crayfish and Asian clam), each comprising ten animals of approximately the same size, were collected during late summer and early fall of 2005 …


Possible Impacts Of Early-11th-, Middle-12th-, And Late-13th-Century Droughts On Western Native Americans And The Mississippian Cahokians, Larry V. Benson, Michael S. Berry, Edward A. Jolie, Jerry D. Spangler, David W. Stahle, Eugene M. Hattori Jan 2007

Possible Impacts Of Early-11th-, Middle-12th-, And Late-13th-Century Droughts On Western Native Americans And The Mississippian Cahokians, Larry V. Benson, Michael S. Berry, Edward A. Jolie, Jerry D. Spangler, David W. Stahle, Eugene M. Hattori

United States Geological Survey: Staff Publications

One or more of three intense and persistent droughts impacted some Native American cultures in the early-11th, middle-12th and late- 13th centuries, including the Anasazi, Fremont, Lovelock, and Mississippian (Cahokian) prehistorical cultures. Tree-ring-based reconstructions of precipitation and temperature indicate that warm drought periods occurred between AD 990 and 1060, AD 1135 and 1170, and AD 1276 and 1297. These droughts occurred during minima in the Pacific Decadal Oscillation and may have been associated with positive values of the Atlantic Multidecadal Oscillation. Each of the Native American cultures was supported, to a greater or lesser degree, by precipitation-dependent resources. Both the …


Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales1, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson Jan 2007

Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales1, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson

United States Geological Survey: Staff Publications

Cumulatively, headwater streams contribute to maintaining hydrologic connectivity and ecosystem integrity at regional scales. Hydrologic connectivity is the water-mediated transport of matter, energy and organisms within or between elements of the hydrologic cycle. Headwater streams compose over two-thirds of total stream length in a typical river drainage and directly connect the upland and riparian landscape to the rest of the stream ecosystem. Altering headwater streams, e.g., by channelization, diversion through pipes, impoundment and burial, modifies fluxes between uplands and downstream river segments and eliminates distinctive habitats. The large-scale ecological effects of altering headwaters are amplified by land uses that alter …


Butterfly Responses To Prairie Restoration Through Fire And Grazing, Jennifer A. Vogel, Diane M. Debinski, Rolf R. Koford, James R. Miller Jan 2007

Butterfly Responses To Prairie Restoration Through Fire And Grazing, Jennifer A. Vogel, Diane M. Debinski, Rolf R. Koford, James R. Miller

United States Geological Survey: Staff Publications

The development of land for modern agriculture has resulted in losses of native prairie habitat. The small, isolated patches of prairie habitat that remain are threatened by fire suppression, overgrazing, and invasion by non-native species. We evaluated the effects of three restoration practices (grazing only, burning only, and burning and grazing) on the vegetation characteristics and butterfly communities of remnant prairies. Total butterfly abundance was highest on prairies that were managed with burning and grazing and lowest on those that were only burned. Butterfly species richness did not differ among any of the restoration practices. Butterfly species diversity was highest …


Evaluation And Comparison Of Gross Primary Production Estimates For The Northern Great Plains Grasslands, Li Zhang, Bruce K. Wylie, Thomas Loveland, Eugene A. Fosnight, Larry L. Tieszen, Lei Ji, Tagir G. Gilmanov Jan 2007

Evaluation And Comparison Of Gross Primary Production Estimates For The Northern Great Plains Grasslands, Li Zhang, Bruce K. Wylie, Thomas Loveland, Eugene A. Fosnight, Larry L. Tieszen, Lei Ji, Tagir G. Gilmanov

United States Geological Survey: Staff Publications

Two spatially-explicit estimates of gross primary production (GPP) are available for the Northern Great Plains. An empirical piecewise regression (PWR) GPP model was developed from flux tower measurements to map carbon flux across the region. The Moderate Resolution Imaging Spectrometer (MODIS) GPP model is a process-based model that uses flux tower data to calibrate its parameters. Verification and comparison of the regional PWR GPP and the global MODIS GPP are important for the modeling of grassland carbon flux. This study compared GPP estimates from PWR and MODIS models with five towers in the grasslands. Among them, PWR GPP and MODIS …


High-Resolution Evidence For Dynamic Transitional Geomagnetic Field Behaviour From A Miocene Reversal, Mcmurdo Sound, Ross Sea, Antarctica, Andrew P. Roberts, Anisch Bakrania, Fabio Florindo, Christopher J. Rowan, Christopher R. Fielding, Ross D. Powell Jan 2007

High-Resolution Evidence For Dynamic Transitional Geomagnetic Field Behaviour From A Miocene Reversal, Mcmurdo Sound, Ross Sea, Antarctica, Andrew P. Roberts, Anisch Bakrania, Fabio Florindo, Christopher J. Rowan, Christopher R. Fielding, Ross D. Powell

Department of Earth and Atmospheric Sciences: Faculty Publications

We report a high-resolution record of a Miocene polarity transition (probably the Chron C6r-C6n transition) from glacimarine sediments in McMurdo Sound, Ross Sea, Antarctica, which is the first transition record reported from high southern latitudes. The transition is recorded in two parallel cores through a 10.7 m stratigraphic thickness. The sediments are interpreted as having been deposited in a marine environment under the influence of floating ice or seaward of a glacier terminus from which a large sediment load was delivered to the drill site. The core was recovered using rotary drilling, which precludes azimuthal orientation of the core and …


Conservation Genetics Of Snowy Plovers (Charadrius Alexandrinus) In The Western Hemisphere: Population Genetic Structure And Delineation Of Subspecies, W. Chris Funk, Thomas D. Mullins, Susan M. Haig Jan 2007

Conservation Genetics Of Snowy Plovers (Charadrius Alexandrinus) In The Western Hemisphere: Population Genetic Structure And Delineation Of Subspecies, W. Chris Funk, Thomas D. Mullins, Susan M. Haig

United States Geological Survey: Staff Publications

We examined the genetic structure of snowy plovers (Charadrius alexandrinus) in North America, the Caribbean, and the west coast of South America to quantify variation within and among breeding areas and to test the validity of three previously recognized subspecies. Sequences (676 bp) from domains I and II of the mitochondrial control region were analyzed for 166 snowy plovers from 20 breeding areas. Variation was also examined at 10 microsatellite loci for 144 snowy plovers from 14 breeding areas. The mtDNA and microsatellite data provided strong evidence that the Puerto Rican breeding group is genetically divergent from sites …


Sexual Selection Drives Speciation In An Amazonian Frog, Kathryn E. Boul, W. Chris Funk, Catherine R. Darst, David C. Cannatella, Michael J. Ryan Jan 2007

Sexual Selection Drives Speciation In An Amazonian Frog, Kathryn E. Boul, W. Chris Funk, Catherine R. Darst, David C. Cannatella, Michael J. Ryan

United States Geological Survey: Staff Publications

One proposed mechanism of speciation is divergent sexual selection, whereby divergence in female preferences and male signals results in behavioural isolation. Despite the appeal of this hypothesis, evidence for it remains inconclusive. Here, we present several lines of evidence that sexual selection is driving behavioural isolation and speciation among populations of an Amazonian frog (Physalaemus petersi). First, sexual selection has promoted divergence in male mating calls and female preferences for calls between neighbouring populations, resulting in strong behavioural isolation. Second, phylogenetic analysis indicates that populations have become fixed for alternative call types several times throughout the species’ range, …


Microsatellite Loci For Distinguishing Spotted Owls (Strix Occidentalis), Barred Owls (Strix Varia), And Their Hybrids, W. Chris Funk, Thomas D. Mullins, Eric D. Forsman, Susan M. Haig Jan 2007

Microsatellite Loci For Distinguishing Spotted Owls (Strix Occidentalis), Barred Owls (Strix Varia), And Their Hybrids, W. Chris Funk, Thomas D. Mullins, Eric D. Forsman, Susan M. Haig

United States Geological Survey: Staff Publications

We identified four diagnostic microsatellite loci that distinguish spotted owls (Strix occidentalis), barred owls (Strix varia), F1 hybrids and backcrosses. Thirty-four out of 52 loci tested (65.4%) successfully amplified, and four of these loci (11.8%) had allele sizes that did not overlap between spotted and barred owls. The probability of correctly identifying a backcross with these four loci is 0.875. Genotyping potential hybrid owls with these markers revealed that field identifications were often wrong. Given the difficulty of identifying hybrids in the field, these markers will be useful for hybrid identification, law enforcement and spotted …


New Insights Into Marine Migration And Winter Habitat Of Gulf Sturgeon, Randy E. Edwards, Frank M. Parauka, Kenneth J. Sulak Jan 2007

New Insights Into Marine Migration And Winter Habitat Of Gulf Sturgeon, Randy E. Edwards, Frank M. Parauka, Kenneth J. Sulak

United States Geological Survey: Staff Publications

Migrations and movements of Gulf sturgeon Acipenser oxyrinchus desotoi were determined using satellite pop-up archival transmitting (PAT) tags and acoustic telemetry. Adult Gulf sturgeon from four rivers in northwestern Florida were caught with gill nets and were tagged with PAT and acoustic tags in the fall of 2001 and 2002. PAT tags were programmed to release in early February 2002 and 2003 to provide information about location of late-winter marine habitats. However, only 5 of 25 provided meaningful location information. Three of the PAT-tagged fish were relocated acoustically near the PAT tag pop-up locations, one of which was in Choctawhatchee …


Dune Fields: Mid-Latitudes, J. Sun, Daniel R. Muhs Jan 2007

Dune Fields: Mid-Latitudes, J. Sun, Daniel R. Muhs

United States Geological Survey: Staff Publications

Large dune fields, or sand seas, are landscapes often thought to be found only in deserts beneath the great, subtropical high-pressure zones, where subsiding air suppresses rainfall. Dune fields are also quite common in mid-latitude regions, to the north and south of subtropical deserts (Fig. 1). Two major characteristics distinguish many mid-latitude dune fields from the sand seas of lower latitudes. One difference is that many of those in mid-latitudes are in semiarid, rather than arid climates, and therefore are not presently active. In this article, ‘active’ refers to eolian sand bodies that are not covered with vegetation, and where …


Fate Of Fish Production In A Seasonally Flooded Saltmarsh, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak Dec 2006

Fate Of Fish Production In A Seasonally Flooded Saltmarsh, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak

United States Geological Survey: Staff Publications

Although saltmarshes are thought to enhance the productivity of open estuarine water, the mechanism by which energy transfer occurs has been debated for decades. One possible mechanism is the transfer of saltmarsh production to estuarine waters by vagile fishes and invertebrates. Monthly estimates of fish standing stock, net fish ingress, and predation were used to develop a bio-mass budget to estimates annual production of fishes and the relative yield to predatory fish, birds, and direct migration to the estuary. Annual production of saltmarsh fishes was estimated to 31.0 gm-2 saltmarsh, which falls within the range of previously reported values …


Deep-Water Antipatharians: Proxies Of Environmental Change, B. Williams, M.J. Risk, S.W. Ross, K.J. Sulak Sep 2006

Deep-Water Antipatharians: Proxies Of Environmental Change, B. Williams, M.J. Risk, S.W. Ross, K.J. Sulak

United States Geological Survey: Staff Publications

Deep-water (307–697 m) antipatharian (black coral) specimens were collected from the southeastern continental slope of the United States and the north-central Gulf of Mexico. The sclerochronology of the specimens indicates that skeletal growth takes place by formation of concentric coeval layers. We used 210Pb to estimate radial growth rate of two specimens, and to establish that they were several centuries old. Bands were delaminated in KOH and analyzed for carbon and nitrogen stable isotopes. Carbon values ranged from _16.4‰ to _15.7‰; the oldest specimen displayed the largest range in values. Nitrogen values ranged from 7.7‰ to 8.6‰. …


Anguilliform Larvae Collected Off North Carolina, Steve W. Ross, Tara L. Casazza, Andrea M. Quattrini, Kenneth J. Sulak Jul 2006

Anguilliform Larvae Collected Off North Carolina, Steve W. Ross, Tara L. Casazza, Andrea M. Quattrini, Kenneth J. Sulak

United States Geological Survey: Staff Publications

The distinctive larval stage of eels (leptocephalus) facilitates dispersal through prolonged life in the open ocean. Leptocephali are abundant and diverse off North Carolina, yet data on distributions and biology are lacking. The water column (from surface to 1,293 m) was sampled in or near the Gulf Stream off Cape Hatteras, Cape Lookout, and Cape Fear, North Carolina during summer through fall of 1999–2005, and leptocephali were collected by neuston net, plankton net, Tucker trawl, and dip net. Additional samples were collected nearly monthly from a transect across southern Onslow Bay, North Carolina (from surface to 91 m) from April …


Guide To Participation For The Andrill Mcmurdo Ice Shelf Project, Andrill Science Management Office, Mcmurdo-Andrill Science Implementation Committee Jan 2006

Guide To Participation For The Andrill Mcmurdo Ice Shelf Project, Andrill Science Management Office, Mcmurdo-Andrill Science Implementation Committee

ANDRILL Project Information

Purpose of This Document

This document is a guide to participation for science team members involved in the McMurdo Ice Shelf (MIS) Project of the ANDRILL Program. The document provides the following information: 1) An overview of the ANtarctic geologic DRILLing (ANDRILL) Program; 2) An overview of expected individual involvement in and commitment to the MIS Project; and 3) Logistical information most relevant to on-ice participants. Information provided in this document will be supplemented by the publication of the MIS Science and Logistics Implementation Plan (SLIP).The SLIP will be available to all MIS ANDRILL participants prior to commencement of drilling. …


Scientific Logistics Implementation Plan For The Andrill Mcmurdo Ice Shelf Project, Timothy R. Naish, Richard H. Levy, Ross D. Powell, Mis Science And Operations Team Members Jan 2006

Scientific Logistics Implementation Plan For The Andrill Mcmurdo Ice Shelf Project, Timothy R. Naish, Richard H. Levy, Ross D. Powell, Mis Science And Operations Team Members

ANDRILL Project Information

Summary

Response of Antarctic ice sheets to projected greenhouse warming of up to 5.8°C by the end of the century is unknown. Models on which predictions are based need to be constrained by geological proxy data from the ancient ice sheets during times when Earth is known to have been warmer than today. The marine-based West Antarctic Ice Sheet (WAIS) and its fringing ice shelves are hypothesized (Clark et al., 2002; Weaver et al., 2003; Stocker, 2003) and documented (Scherer et al., 1998) to have collapsed during past “super-interglacial” warm extremes when global sea-level was more than 5m higher than …


The Sparrow Surface Water-Quality Model: Theory, Application And User Documentation, G. E. Schwarz, A. B. Hoos, R. B. Alexander, R. A. Smith Jan 2006

The Sparrow Surface Water-Quality Model: Theory, Application And User Documentation, G. E. Schwarz, A. B. Hoos, R. B. Alexander, R. A. Smith

United States Geological Survey: Publications

SPARROW (SPAtially Referenced Regressions On Watershed attributes) is a watershed modeling technique for relating water-quality measurements made at a network of monitoring stations to attributes of the watersheds containing the stations. The core of the model consists of a nonlinear regression equation describing the non-conservative transport of contaminants from point and diffuse sources on land to rivers and through the stream and river network. The model predicts contaminant flux, concentration, and yield in streams and has been used to evaluate alternative hypotheses about the important contaminant sources and watershed properties that control transport over large spatial scales.

This report provides …


Predicting The Percent Live Cover Of Corals: An In Situ Remote Sensing Approach, Deepak R. Mishra, Sunil Narumalani, Ronald Bahl, D. Rundquist, Merlin P. Lawson Jan 2006

Predicting The Percent Live Cover Of Corals: An In Situ Remote Sensing Approach, Deepak R. Mishra, Sunil Narumalani, Ronald Bahl, D. Rundquist, Merlin P. Lawson

Center for Advanced Land Management Information Technologies: Publications

Percent reflectance of corals is perhaps the most important remotely sensed data that can be related to their biophysical properties. Because most of the biophysical variables of corals (i.e., pigment content, live cover and algal overgrowth) are related to their reflectance spectra, the analysis and inversion of the spectra may provide an account of these variables. Our research was aimed at determining the relationship between the percent live cover and reflectance of corals. Two wavelength bands (405–425 nm, and 590–600 nm) were identified to establish the relationship. A linear relationship was observed, which showed higher correlation (R2 = …


Taxonomic Considerations In Listing Subspecies Under The U.S. Endangered Species Act, Susan M. Haig, Erik A. Beever, Steven M. Chambers, Hope M. Draheim, Bruce D. Dugger, Susie M. Dunham, Elise Elliott-Smith, Joseph B. Fontaine, Dylan C. Kesler, Brian J. Knaus, Iara F. Lopes, Pete Loschl, Thomas D. Mullins, Lisa M. Sheffield Jan 2006

Taxonomic Considerations In Listing Subspecies Under The U.S. Endangered Species Act, Susan M. Haig, Erik A. Beever, Steven M. Chambers, Hope M. Draheim, Bruce D. Dugger, Susie M. Dunham, Elise Elliott-Smith, Joseph B. Fontaine, Dylan C. Kesler, Brian J. Knaus, Iara F. Lopes, Pete Loschl, Thomas D. Mullins, Lisa M. Sheffield

United States Geological Survey: Staff Publications

The U.S. Endangered Species Act (ESA) allows listing of subspecies and other groupings below the rank of species. This provides the U.S. Fish and Wildlife Service and the National Marine Fisheries Service with a means to target the most critical unit in need of conservation. Although roughly one-quarter of listed taxa are subspecies, these management agencies are hindered by uncertainties about taxonomic standards during listing or delisting activities. In a review of taxonomic publications and societies, we found few subspecies lists and none that stated standardized criteria for determining subspecific taxa. Lack of criteria is attributed to a centuries-old debate …


Conserving Biodiversity In Human-Dominated Landscapes, Dale D. Goble, J. Michael Scott, Frank W. Davis Jan 2006

Conserving Biodiversity In Human-Dominated Landscapes, Dale D. Goble, J. Michael Scott, Frank W. Davis

United States Geological Survey: Staff Publications

The two volumes of The Endangered Species Act at Thirty look backward to evaluate the effectiveness of the act over its first three decades (Wilcove and McMillan 2006; Scott et al. 2006, chap. 2; Goble, this volume; Svancara, this volume; Callicott, this volume; Norton, this volume) and also forward to suggest how it can be used as a cornerstone for conserving biological diversity in increasingly human-dominated landscapes (Davis et al. 2006; Bean 2006). The chapters in part 2 of this volume, for example, appraise the science of the 1990s and 2000s at both the large scale (Lomolino, this volume; Naeem …


Endangered Species Time Line, Leona K. Svancara, J. Michael Scott, Dale D. Goble, Frank W. Davis, Donna Brewer Jan 2006

Endangered Species Time Line, Leona K. Svancara, J. Michael Scott, Dale D. Goble, Frank W. Davis, Donna Brewer

United States Geological Survey: Staff Publications

The Endangered Species Act (ESA) is embedded in a web of statutes designed to regulate relationships between humans and other species that stretch back nearly a millennium (Goble, this volume; Goble and Freyfogle 2002). This chapter presents a time line of federal actions taken to protect wildlife beginning with passage of the Land and Water Conservation Fund Act in 1963 (Act of May 28, 1963). Earlier laws to protect wildlife are discussed elsewhere (Goble, this volume). The time line emphasizes federal actions that conserve species at risk of extinction and significant events in the course of implementing the Endangered Species …


Isotope Sourcing Of Prehistoric Willow And Tule Textiles Recovered From Western Great Basin Rock Shelters And Caves: Proof Of Concept, Larry V. Benson, E. M. Hattori, H. E. Taylor, S. R. Poulson, E. A. Jolie Jan 2006

Isotope Sourcing Of Prehistoric Willow And Tule Textiles Recovered From Western Great Basin Rock Shelters And Caves: Proof Of Concept, Larry V. Benson, E. M. Hattori, H. E. Taylor, S. R. Poulson, E. A. Jolie

United States Geological Survey: Staff Publications

Isotope and trace-metal analyses were used to determine the origin of plants used to manufacture prehistoric textiles (basketry and matting) from archaeological sites in the western Great Basin. Research focused on strontium (87Sr/86Sr) and oxygen (18O/16O) isotope ratios of willow (Salix sp.) and tule (Schoenoplectus sp.), the dominant raw materials in Great Basin textiles. The oxygen-isotope data indicated that the willow and tule used to produce the textiles were harvested from the banks of rivers or in marshes characterized by flowing water and not from lakes or sinks. The strontium-isotope …


The Agricultural Productivity Of Chaco Canyon And The Source(S) Of Pre-Hispanic Maize Found In Pueblo Bonito, Larry Benson, John Stein, Howard Taylor, Richard Friedman, Thomas C. Windes Jan 2006

The Agricultural Productivity Of Chaco Canyon And The Source(S) Of Pre-Hispanic Maize Found In Pueblo Bonito, Larry Benson, John Stein, Howard Taylor, Richard Friedman, Thomas C. Windes

United States Geological Survey: Staff Publications

Agricultural productivity estimates suggest that the core area of Chaco Canyon could have sustained only a few hundred individuals. Modern analogues of existing Pueblo populations and their domestic habitations with Chaco structures suggest that Chaco at times had a resident population exceeding 2000 people. These data suggest that maize would have had to be imported to feed permanent residents and those visiting Chaco during ritual–political gatherings and those who participated in the accelerated construction and modification of great houses between AD 1030 and 1130. Comparison of strontium-isotope and trace-element ratios of synthetic soil and natural waters from sites within the …


The Earth All Around Us: Selected Building Stone In Lincoln, Nebraska. A Walking Tour, William J. Wayne Jan 2006

The Earth All Around Us: Selected Building Stone In Lincoln, Nebraska. A Walking Tour, William J. Wayne

Department of Earth and Atmospheric Sciences: Faculty Publications

Stone has been a primary building material for millennia. Cities, therefore, are treasure troves of earth materials. A wide variety of stones from many places are used for walls, as foundations to support entire buildings, as trim, and more recently as cladding (facing, an overlay). The Earth science teacher can find, in the limited space of an urban environment, a superb collection of stones with which to introduce students to these materials. The surfaces of stones on the outsides of buildings illustrate the durability and the vulnerability of each kind of stone to the local climate. And the history of …


Use Of Mammal Manure By Nesting Burrowing Owls: A Test Of Four Functional Hypotheses, Matthew D. Smith, Courtney J. Conway Jan 2006

Use Of Mammal Manure By Nesting Burrowing Owls: A Test Of Four Functional Hypotheses, Matthew D. Smith, Courtney J. Conway

United States Geological Survey: Staff Publications

Animals have evolved an impressive array of behavioural traits to avoid depredation. Olfactory camouflage of conspicuous odours is a strategy to avoid depredation that has been implicated only in a few species of birds. Burrowing owls, Athene cunicularia, routinely collect dried manure from mammals and scatter it in their nest chamber, in the tunnel leading to their nest and at the entrance to their nesting burrow. This unusual behaviour was thought to reduce nest depredation by concealing the scent of adults and juveniles, but a recent study suggests that manure functions to attract arthropod prey. However, burrowing owls routinely …


Renewing The Conservation Commitment, Frank W. Davis, Dale D. Goble, J. Michael Scott Jan 2006

Renewing The Conservation Commitment, Frank W. Davis, Dale D. Goble, J. Michael Scott

United States Geological Survey: Staff Publications

As we write this in early 2005 there are several ESA-related pieces of legislation pending before Congress. Most of the proposed legislation is championed by Republican leaders from western states, who promise to strengthen the use of science or ensure fairer treatment of private landowners. Ir has become a perennial drama on the American political stage: "conservatives" rally to rein in a law that they believe has reached too far and "conservationists" mobilize ro defend the law that they believe offers the best ho pe for protecting biodiversity from relentless economic exploitation. There is much posturing, finger pointing, and, ultimately, …