Science synthesis to support socioecological resilience in the Sierra Nevada and southern Cascade Range

Treesearch

Jonathan W. Long; Lenya Quinn-Davidson; Carl N. Skinner

2014-01-01

A team of scientists integrated recent research to inform forest managers, stakeholders, and interested parties concerned with promoting socioecological resilience in the Sierra Nevada, southern Cascade Range, and Modoc Plateau. Among the focal topics were forest and fire ecology; soils; aquatic ecosystems; forest carnivores including Pacific fisher, marten, and...

77 FR 74688 - Final Recovery Plan, First Revision; Mexican Spotted Owl

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-17

... Arizona, Colorado, New Mexico, Texas, and Utah, and south through the Sierra Madre Occidental and Sierra Madre Oriental in Mexico. The recovery plan includes specific recovery objectives and criteria to be met...). The revised recovery plan was prepared by a team of experts from both the United States and Mexico...

Achieving a nexus of science, management, and policy in the Sierra Nevada

Treesearch

Peter A. Stine; Dennis D. Murphy

2004-01-01

The policies and strategies that guide the use and management of lands in the Sierra Nevada ecoregion depend on objective scientific information. In recent years, the region has attracted increasing attention from visitors, developers, environmentalists, businesses, scientists, and politicians as well as local residents, resource managers, and research groups. And the...

Youth Reintegration Training and Education for Peace (YRTEP) Program: Sierra Leone, 2000-2001. Impact Evaluation.

ERIC Educational Resources Information Center

Fauth, Gloria; Daniels, Bonnie

Management Systems International (MSI), with funding from United States Agency for International Development Office of Transition Initiatives (USAID/OTI) and in coordination with other partners, is implementing a program in Sierra Leone entitled "Youth Reintegration Training and Education for Peace" (YRTEP). The object is to provide…

Power in Practice: Trade Union Education in Sierra Leone

ERIC Educational Resources Information Center

Stirling, John

2013-01-01

This article presents an analysis of the development of a trade union education program in Sierra Leone in the geo-historical context of British colonialism. It places the argument in relation to the contradictory trends of trade unionism more generally and alongside their antagonistic cooperation with capitalism. It discusses the limits and…

Linking Research, Extension and Farmers: The Case of Mangrove Swamp Rice Cultivation in Sierra Leone.

ERIC Educational Resources Information Center

Zinnah, Moses Moroe

1994-01-01

Interviews with 124 rice farmers in Sierra Leone revealed that farmers and extension staff have minimal participation and input in testing of new cultivation technologies. The top-down research approach has limited contact among researchers, extension staff, and farmers and affected the utility and application of research. (SK)

Wildfire impacts on California spotted owl nesting habitat in the Sierra Nevada

Treesearch

Scott L. Stephens; Jay D. Miller; Brandon M. Collins; Malcolm P. North; John J. Keane; Susan L. Roberts

2016-01-01

California spotted owls (CSOs) (Strix occidentalis occidentalis) have received significant conservation attention beginning with the U.S. Forest Service interim management guidelines in 1992. The most commonly reported forest habitat feature for successful nesting habitat of CSO is canopy cover > 70%. Loss and degradation of Sierra Nevada CSO habitat, however,...

Concerning KAr dating of a basalt flow from the Tahoe-Tioga interglaciation, Sawmill Canyon, southeastern Sierra Nevada, California

USGS Publications Warehouse

Dalrymple, G.B.; Burke, R.M.; Birkeland, P.W.

1982-01-01

New KAr ages for a basalt flow interbedded with Tahoe and Tioga tills in Sawmill Canyon, southeastern Sierra Nevada, slightly refine previously published ages for the flow and provide an estimate of 53,000 ± 44,000 yr for the Tahoe-Tioga interglaciation.

Riparian Communities of the Sierra Nevada and their Environmental Relationships

Treesearch

Richard R. Harris

1989-01-01

Data on riparian community composition and environmental conditions were collected on over 20 streams in the Sierra Nevada as part of hydropower licensing studies. Over 1,000 samples were analyzed using two-way indicator species analysis (TWINSPAN), to determine riparian dominance types. Ordination techniques were applied to evaluate associations between environmental...

REGIONAL ANALYSIS OF INORGANIC NITROGEN YIELD AND RETENTION IN HIGH-ELEVATION ECOSYSTEMS OF THE SIERRA NEVADA AND ROCKY MOUNTAINS

EPA Science Inventory

Yields and retention of inorganic nitrogen (DIN) and nitrate concentrations in surface runoff are summarized for 28 high elevation watersheds in the Sierra Nevada, California and Rocky Mountains of Wyoming and Colorado. Catchments ranged in elevation from 2475 to 3603 m and from...

Nest trees of northern flying squirrels in the Sierra Nevada

Treesearch

Marc D. Meyer; Douglas A. Kelt; Malcolm P. North

2005-01-01

We examined the nest-tree preferences of northern flying squirrels (Glaucomys sabrinus) in an old-growth, mixed-conifer and red fir (Abies magnifica) forest of the southern Sierra Nevada of California. We tracked 27 individuals to 122 nest trees during 3 summers. Flying squirrels selected nest trees that were larger in diameter and...

Sierra Leone's Former Child Soldiers: A Longitudinal Study of Risk, Protective Factors, and Mental Health

ERIC Educational Resources Information Center

Betancourt, Theresa S.; Brennan, Robert T.; Rubin-Smith, Julia; Fitzmaurice, Garrett M.; Gilman, Stephen E.

2010-01-01

Objective: To investigate the longitudinal course of internalizing and externalizing problems and adaptive/prosocial behaviors among Sierra Leonean former child soldiers and whether postconflict factors contribute to adverse or resilient mental health outcomes. Method: Male and female former child soldiers (N = 260, aged 10 to 17 years at…

Current and projected condition of mid-elevation Sierra Nevada forests

Treesearch

Malcolm P. North; Mark W. Schwartz; Brandon M. Collins; John J. Keane

2017-01-01

Most of the California spotted owl’s (Strix occidentalis occidentalis) habitat is concentrated in mid-elevation forests of the Sierra Nevada (see chapter 9 for a discussion of southern California spotted owls and their habitat), which are made up primarily of ponderosa pine (Pinus ponderosa Lawson & C. Lawson), mixed-...

Culture and environment in the Sierra de Misantla, Veracruz, Mexico: the case of Oecopetalum mexicanum

Treesearch

Maite Lascurain; Citlalli Lopez-Binnquist; Marla R. Emery

2016-01-01

We analyze the cultural and environmental dimensions of foraging the wild edible fruit cachichín (Oecopetalum mexicanum) in the Sierra de Misantla in central Veracruz, Mexico, including gathering practices, social organization, subsistence, commerce, and consumption. Gathering cachichín brings...

A previously undiscovered group of chimpanzees (Pan troglodytes verus) is observed living in the Tonkolili district of Sierra Leone.

PubMed

Halloran, Andrew R; Cloutier, Christina T; Sesay, Papanie Bai

2013-06-01

A previously undocumented group of wild chimpanzees (Pan troglodytes verus) was recently discovered along the Pampana River in the Tonkolili District of Sierra Leone. Based on interviews from local residents (N = 6), we estimate the group size to be approximately 30 individuals. Though this population does not show up in the most recent census of chimpanzees in Sierra Leone, it concurs with findings that indicate most of the chimpanzees in Sierra Leone live scattered throughout the country alongside villages, rather than in protected areas. During a three-week observation in the area, two chimpanzees were hunted and killed. The reason for these deaths, along with other reported instances of hunting in the area, are primarily due to crop-raiding and competition for resources between chimpanzees and humans. We conclude that this is a heavily imperiled population. Based on the ecology of the area and composition of local villages, we propose a number of conservation strategies that will promote a symbiotic relationship between the chimpanzees and human populations residing in the area. © 2013 Wiley Periodicals, Inc.

Airborne SAR determination of relative ages of Walker Valley moraines, eastern Sierra Nevada

NASA Technical Reports Server (NTRS)

Fox, A.; Isacks, B.; Bloom, A.; Fielding, E.; Mcmurry, D.

1991-01-01

A regional study of the distribution and elevations of Pleistocene moraines in the Andes requires a method of determining relative age from space. One of our primary objectives is to establish the relative chronology of major climatic events responsible for glaciation in the Andes and other regions that are difficult to access on the ground and where suitable material for absolute age determination is lacking. The sensitivity of radar to surface roughness makes it possible to develop a remotely-based relative dating technique for landforms for which surface age and roughness can be correlated. We are developing such a technique with Airborne Synthetic Aperture Radar (AIRSAR) imagery of the eastern Sierra Nevada where independent evidence is available for the ages and physical characteristics of moraines. The Sierra Nevada moraines are similar in form and environmental setting to Andean moraines that we have targeted for study during the pending Shuttle Imaging Radar-C (SIR-C) mission. SAR imagery is used to differentiate the ages of five moraine sequences of Walker Valley in the eastern Sierra Nevada. Other aspects of this investigation are briefly discussed.

Precipitation structure in the Sierra Nevada of California during winter

USGS Publications Warehouse

Pandey, G.R.; Cayan, D.R.; Georgakakos, K.P.

1999-01-01

Influences of upper air characteristics along the coast of California upon wintertime (November-April) precipitation in the Sierra Nevada are investigated. Precipitation events in the Sierra Nevada region occur mostly during wintertime, irrespective of station location (leeside or wihdside) and elevation. Most precipitation episodes in the region are associated with moist southwesterly winds (coming from the southwest direction) and also tend to occur when the 700-mbar temperature at the upwind direction is close to -2??C. This favored wind direction and temperature signify the importance of both moisture transport and orographic lifting in augmenting precipitation in the region. By utilizing the observed dependency of the precipitation upon the upper air conditions, a linear model is formulated to quantify the precipitation observed at different sites as a function of moisture transport. The skill of the model increases with timescale of aggregation, reaching more than 50% variance explained at an aggregation period of 5-7 days. This indicates that upstream air moisture transport can be used to estimate the precipitation totals in the Sierra Nevada region. Copyright 1999 by the American Geophysical Union.

Swimming with the Shoal

NASA Astrophysics Data System (ADS)

Childs, Ann

2017-10-01

This article responds to Yuli Rahmawati and Peter Charles Taylor's piece and explores my role as a science teacher, science teacher educator and researcher in two contexts, Sierra Leone and Bhutan. In the first part of the article I reflect on my 3 years as a science teacher in Sierra Leone and demonstrate resonances with Yuli's accounts of culture shock and with her positioning of herself in a third space. I also reflect on the importance of colleagues in helping me reshape my identity as a science teacher in this new context. The second part of the article reflects on much shorter periods of time in Bhutan and my work as a teacher educator and researcher where, unlike Sierra Leone, it was not possible because of the short periods I worked there, to occupy a third space. I close by discussing how in Bhutan, but also Sierra Leone, collaboration with colleagues allowed me to contribute my own expertise, despite my lack of a deep understanding of the cultural context, in a way that was as valuable as possible. I liken this way of collaborative working in my professional life as `swimming with the shoal'.

The tectonic significance of K/Ar illite fine-fraction ages from the San Luis Formation (Eastern Sierras Pampeanas, Argentina)

NASA Astrophysics Data System (ADS)

Wemmer, Klaus; Steenken, André; Müller, Stefan; de Luchi, Mónica G. López; Siegesmund, Siegfried

2011-04-01

The Sierra de San Luis forms the southern tip of the Eastern Sierras Pampeanas in central Argentina. Two narrow belts of low-grade phyllites and quartz arenites, i.e. the San Luis Formation, have accommodated part of the strain-related differential exhumation of the medium- to high-grade metamorphic domains that constitute to the basement complex of the sierra. Eleven phyllite samples were subjected to the K/Ar fine-fraction dating technique. Results are interpreted in relation to the Kübler index of the illites, which indicate epimetamorphic conditions for the majority of the samples. Obtained ages between 330 and 290 Ma cover a period of compressional tectonics in the late Mississippian (Visean/Serpukhovian boundary) followed by the subsidence during the formation of the Paganzo Basin in the provinces of La Rioja and San Luis. These tectonic movements are coincident with the Toco orogeny in northern Chile and southern Bolivia. This suggests that the older K/Ar ages document the compressional stage and that younger ages record the cooling of the basement during the subsequent extensional uplift of the basement.

Good laboratory practices guarantee biosafety in the Sierra Leone-China friendship biosafety laboratory.

PubMed

Wang, Qin; Zhou, Wei-Min; Zhang, Yong; Wang, Huan-Yu; Du, Hai-Jun; Nie, Kai; Song, Jing-Dong; Xiao, Kang; Lei, Wen-Wen; Guo, Jian-Qiang; Wei, He-Jiang; Cai, Kun; Wang, Yan-Hai; Wu, Jiang; Kamara, Gerard; Kamara, Idrissa; Wei, Qiang; Liang, Mi-Fang; Wu, Gui-Zhen; Dong, Xiao-Ping

2016-06-23

The outbreak of Ebola virus disease (EVD) in West Africa between 2014 and 2015 was the largest EDV epidemic since the identification of Ebola virus (EBOV) in 1976, and the countries most strongly affected were Sierra Leone, Guinea, and Liberia. The Sierra Leone-China Friendship Biological Safety Laboratory (SLE-CHN Biosafety Lab), a fixed Biosafety Level 3 laboratory in the capital city of Sierra Leone, was established by the Chinese government and has been active in EBOV detection since 11 March 2015. Complete management and program documents were created for the SLE-CHN Biosafety Lab, and it was divided into four zones (the green, yellow, brown, and red zones) based on the risk assessment. Different types of safe and appropriate personnel protection equipment (PPE) are used in different zones of the laboratory, and it fully meets the Biosafety Level 3 laboratory standards of the World Health Organization. Good preparedness, comprehensive risk assessment and operation documents, appropriate PPE, effective monitoring and intensive training, together with well-designed and reasonable laboratory sectioning are essential for guaranteeing biosafety.

Magma mixing in granitic rocks of the central Sierra Nevada, California

NASA Astrophysics Data System (ADS)

Reid, John B.; Evans, Owen C.; Fates, Dailey G.

1983-12-01

The El Capitan alaskite exposed in the North American Wall, Yosemite National Park, was intruded by two sets of mafic dikes that interacted thermally and chemically with the host alaskite. Comparisons of petrographic and compositional data for these dikes and alaskite with published data for Sierra Nevada plutons lead us to suggest that mafic magmas were important in the generation of the Sierra Nevada batholith. Specifically, we conclude that: (1) intrusion of mafic magmas in the lower crust caused partial melting and generation of alaskite (rhyolitic) magmas; (2) interaction between the mafic and felsic magmas lead to the observed linear variation diagrams for major elements; (3) most mafic inclusions in Sierra Nevada plutons represent chilled pillows of mafic magmas, related by fractional crystallization and granitoid assimilation, that dissolve into their felsic host and contaminate it to intermediate (granodioritic) compositions; (4) vesiculation of hydrous mafic magma upon chilling may allow buoyant mafic inclusions and their disaggregation products to collect beneath a pluton's domed ceiling causing the zoning (mafic margins-to-felsic core) that these plutons exhibit.

Individual and community perceptions of surgical care in Sierra Leone.

PubMed

Groen, Reinou S; Sriram, Veena M; Kamara, Thaim B; Kushner, Adam L; Blok, Lucie

2014-01-01

To determine themes and beliefs that influence health-seeking behaviour and barriers to accessing surgical care. In January 2012 in Western Area Province of Sierra Leone, six Focus Group Discussions (FGDs) were conducted. The FDGs consisted of three male only and three female only groups in an urban, a slum and a rural setting. Researchers investigated a wide range of topics including definitions of surgery, types of surgical procedures, trust, quality of care, human resources, post-operative care, permission-seeking and traditional beliefs. Although many individual beliefs were expressed, common fears were as follows: becoming half human after surgery; complications from procedures; stigma from having a scar; and financial burdens resulting from the cost of care. Participants also expressed concern about the quality of the care available in Sierra Leone. The concept of being half human after surgery, previously not documented in the literature, is noteworthy and should be explored more fully. Qualitative research in other parts of Sierra Leone and other LMICs into beliefs of the local population could improve programmes for access and delivery of surgical care. © 2013 John Wiley & Sons Ltd.

An isotopic study of the Coso, California, geothermal area

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fournier, R.O.; Thompson, J.M.

1982-10-01

Thirty-nine water samples were collected from the Coso geothermal system and vicinity and were analyzed for major chemical constituents and deltaD and delta/sup 18/O. Non-thermal ground waters from the Coso Range were found to be isotopically heavier than non-thermal ground waters from the Sierra Nevada to the west. The deltaD value for the deep thermal water at Coso is similar to that of the Sierra water, suggesting that the major recharge for the hydrothermal system comes from the Sierra Nevada rather than from local precipitation on the Coso Range. The delta/sup 18/O values of the thermal water are about 7/supmore » 0//00 heavier than those of the Sierra water. This shift in delta/sup 18/O is the result of water-rock reaction at high temperatures, and the magnitude of the shift indicates that the ratio of rock to total water has been large for the system up to its present stage of development. The isotopic data are compatible with the geochemical model previously proposed by Fournier.« less

Evaluating the utility of detrital thermochronometric studies: detrital laser ablation (U-Th)/He dating and conventional bedrock zircon (U-Th)/He analyses from the eastern Sierra Nevada, California

NASA Astrophysics Data System (ADS)

Horne, A.; Hodges, K. V.; Van Soest, M. C.

2016-12-01

Recent applications of the newly developed `laser ablation double dating' (LADD) technique, an integrated laser microprobe U/Pb and (U-Th)/He dating method, have showcased the potential utility of LADD for detrital thermochronologic studies. However, detrital thermochronologic techniques rely on confidence that detrital data adequately represent the full range of bedrock cooling ages within a catchment. To test this primary assumption, we compare (U-Th)/He zircon ages from age-elevation transects to LADD (U-Th)/He zircon ages from modern fluvial detritus collected at the range front in the eastern Sierra Nevada, California. Terminated by a normal fault escarpment, the small, steep catchments along the eastern side of the Sierra Nevada batholith are apropos locations for comparing the ability of detrital data to deduce the exhumation history of a source terrain with standard age-elevation transects. Additionally, the exhumation of the Sierra Nevada batholith is also intriguing, as past evaluations of the post-emplacement exhumation history of the range have yielded discrepant results. Thus far, analyses from the southern extent of the eastern Sierra Nevada show narrow ranges of cooling ages consistent with simple, relatively rapid exhumation. Ongoing analyses will expand the dataset such that we can fully compare bedrock and detrital age ranges as well as characterize the exhumation history of the range with a thermochronometer that has not been used to date the batholith.

When free healthcare is not free. Corruption and mistrust in Sierra Leone's primary healthcare system immediately prior to the Ebola outbreak.

PubMed

Pieterse, Pieternella; Lodge, Tom

2015-11-01

Sierra Leone is one of three countries recently affected by Ebola. In debates surrounding the circumstances that contributed to the initial failure to contain the outbreak, the word 'trust' is often used: In December 2014, WHO director Margret Chan used 'lack of trust in governments'; The Lancet's Editor-in-Chief, wrote how Ebola has exposed the '… breakdown of trust between communities and their governments.' This article explores the lack of trust in public healthcare providers in Sierra Leone, predating the Ebola outbreak, apparently linked to widespread petty corruption in primary healthcare facilities. It compares four NGO-supported accountability interventions targeting Sierra Leone's primary health sector. Field research was conducted in Kailahun, Kono and Tonkolili Districts, based on interviews with health workers and focus group discussions with primary healthcare users. Field research showed that in most clinics, women and children entitled to free care routinely paid for health services. A lack of accountability in Sierra Leone's health sector appears pervasive at all levels. Petty corruption is rife. Understaffing leads to charging for free care in order to pay clinic-based 'volunteers' who function as vaccinators, health workers and birth attendants. Accountability interventions were found to have little impact on healthworker (mis)behaviour. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

GPS Imaging of vertical land motion in California and Nevada: Implications for Sierra Nevada uplift

NASA Astrophysics Data System (ADS)

Hammond, William C.; Blewitt, Geoffrey; Kreemer, Corné

2016-10-01

We introduce Global Positioning System (GPS) Imaging, a new technique for robust estimation of the vertical velocity field of the Earth's surface, and apply it to the Sierra Nevada Mountain range in the western United States. Starting with vertical position time series from Global Positioning System (GPS) stations, we first estimate vertical velocities using the MIDAS robust trend estimator, which is insensitive to undocumented steps, outliers, seasonality, and heteroscedasticity. Using the Delaunay triangulation of station locations, we then apply a weighted median spatial filter to remove velocity outliers and enhance signals common to multiple stations. Finally, we interpolate the data using weighted median estimation on a grid. The resulting velocity field is temporally and spatially robust and edges in the field remain sharp. Results from data spanning 5-20 years show that the Sierra Nevada is the most rapid and extensive uplift feature in the western United States, rising up to 2 mm/yr along most of the range. The uplift is juxtaposed against domains of subsidence attributable to groundwater withdrawal in California's Central Valley. The uplift boundary is consistently stationary, although uplift is faster over the 2011-2016 period of drought. Uplift patterns are consistent with groundwater extraction and concomitant elastic bedrock uplift, plus slower background tectonic uplift. A discontinuity in the velocity field across the southeastern edge of the Sierra Nevada reveals a contrast in lithospheric strength, suggesting a relationship between late Cenozoic uplift of the southern Sierra Nevada and evolution of the southern Walker Lane.

Lassa Fever in Post-Conflict Sierra Leone

PubMed Central

Hartnett, Jessica N.; Levy, Danielle C.; Yenni, Rachael E.; Moses, Lina M.; Fullah, Mohammed; Momoh, Mambo; Fonnie, Mbalu; Fonnie, Richard; Kanneh, Lansana; Koroma, Veronica J.; Kargbo, Kandeh; Ottomassathien, Darin; Muncy, Ivana J.; Jones, Abigail B.; Illick, Megan M.; Kulakosky, Peter C.; Haislip, Allyson M.; Bishop, Christopher M.; Elliot, Deborah H.; Brown, Bethany L.; Zhu, Hu; Hastie, Kathryn M.; Andersen, Kristian G.; Gire, Stephen K.; Tabrizi, Shervin; Tariyal, Ridhi; Stremlau, Mathew; Matschiner, Alex; Sampey, Darryl B.; Spence, Jennifer S.; Cross, Robert W.; Geisbert, Joan B.; Folarin, Onikepe A.; Happi, Christian T.; Pitts, Kelly R.; Geske, F. Jon; Geisbert, Thomas W.; Saphire, Erica Ollmann; Robinson, James E.; Wilson, Russell B.; Sabeti, Pardis C.; Henderson, Lee A.; Khan, S. Humarr; Bausch, Daniel G.; Branco, Luis M.; Garry, Robert F.

2014-01-01

Background Lassa fever (LF), an often-fatal hemorrhagic disease caused by Lassa virus (LASV), is a major public health threat in West Africa. When the violent civil conflict in Sierra Leone (1991 to 2002) ended, an international consortium assisted in restoration of the LF program at Kenema Government Hospital (KGH) in an area with the world's highest incidence of the disease. Methodology/Principal Findings Clinical and laboratory records of patients presenting to the KGH Lassa Ward in the post-conflict period were organized electronically. Recombinant antigen-based LF immunoassays were used to assess LASV antigenemia and LASV-specific antibodies in patients who met criteria for suspected LF. KGH has been reestablished as a center for LF treatment and research, with over 500 suspected cases now presenting yearly. Higher case fatality rates (CFRs) in LF patients were observed compared to studies conducted prior to the civil conflict. Different criteria for defining LF stages and differences in sensitivity of assays likely account for these differences. The highest incidence of LF in Sierra Leone was observed during the dry season. LF cases were observed in ten of Sierra Leone's thirteen districts, with numerous cases from outside the traditional endemic zone. Deaths in patients presenting with LASV antigenemia were skewed towards individuals less than 29 years of age. Women self-reporting as pregnant were significantly overrepresented among LASV antigenemic patients. The CFR of ribavirin-treated patients presenting early in acute infection was lower than in untreated subjects. Conclusions/Significance Lassa fever remains a major public health threat in Sierra Leone. Outreach activities should expand because LF may be more widespread in Sierra Leone than previously recognized. Enhanced case finding to ensure rapid diagnosis and treatment is imperative to reduce mortality. Even with ribavirin treatment, there was a high rate of fatalities underscoring the need to develop more effective and/or supplemental treatments for LF. PMID:24651047

Population declines lead to replicate patterns of internal range structure at the tips of the distribution of the California red-legged frog (Rana draytonii)

USGS Publications Warehouse

Richmond, Jonathan Q.; Backlin, Adam R.; Tatarian, Patricia J.; Solvesky, Ben G.; Fisher, Robert N.

2014-01-01

Demographic declines and increased isolation of peripheral populations of the threatened California red-legged frog (Rana draytonii) have led to the formation of internal range boundaries at opposite ends of the species’ distribution. While the population genetics of the southern internal boundary has been studied in some detail, similar information is lacking for the northern part of the range. In this study, we used microsatellite and mtDNA data to examine the genetic structuring and diversity of some of the last remaining R. draytonii populations in the northern Sierra Nevada, which collectively form the northern external range boundary. We compared these data to coastal populations in the San Francisco Bay Area, where the species is notably more abundant and still exists throughout much of its historic range. We show that ‘external’ Sierra Nevada populations have lower genetic diversity and are more differentiated from one another than their ‘internal’ Bay Area counterparts. This same pattern was mirrored across the distribution in California, where Sierra Nevada and Bay Area populations had lower allelic variability compared to those previously studied in coastal southern California. This genetic signature of northward range expansion was mirrored in the phylogeography of mtDNA haplotypes; northern Sierra Nevada haplotypes showed greater similarity to haplotypes from the south Coast Ranges than to the more geographically proximate populations in the Bay Area. These data cast new light on the geographic origins of Sierra Nevada R. draytonii populations and highlight the importance of distinguishing the genetic effects of contemporary demographic declines from underlying signatures of historic range expansion when addressing the most immediate threats to population persistence. Because there is no evidence of contemporary gene flow between any of the Sierra Nevada R. draytonii populations, we suggest that management activities should focus on maintaining and creating additional ponds to support breeding within typical dispersal distances of occupied habitat.

Reconstruction of 20th Century Atmospheric Deposition Rates in the Sierra Nevada (California) using Spheroidal Carbonaceous Particles

NASA Astrophysics Data System (ADS)

Heard, A.; Sickman, J. O.; Rose, N.

2012-12-01

Atmospheric nitrogen deposition is altering biogeochemical cycles and ecological processes in high-elevation aquatic ecosystems. A need for stricter standards based on measurable ecological effects has been identified as an important step towards their long-term protection. One of the challenges with identifying ecological thresholds is a lack of knowledge of background conditions (pre- industrial) and changes that may have occurred prior to extensive monitoring programs. However, this information can be obtained using paleolimnological approaches. We are investigating historic atmospheric deposition in the Sierra Nevada using spheroidal carbonaceous particles (SCPs) in lake sediments. SCPs are strong geochemical indicators of anthropogenic atmospheric deposition because they are only produced by industrial combustion of fossil fuels---there are no natural sources. We detected SCPs as early as 1870 at Moat Lake in the eastern Sierra Nevada. SCP concentrations increased over time, peaking in the mid-1980's (2,399 gDM-1) while SCP accumulation rates peaked in the early 1920's (105 no, cm-2 yr-1) (Figure 1). Lakes along the western slope of the Sierra (Pear and Emerald) show similar patterns although differences vary by site and are likely explained by watershed characteristics and proximity to emission sources. SCP concentrations at Pear and Emerald lakes peak 10-15 years earlier than Moat. A consistent decrease was observed at Pear and Moat following the peak concentrations until present. Present day concentrations are 556 gDM-1 at Moat and 473 gDM-1 at Pear. At Emerald lake SCPs also initially decreased starting in 1964, but an increasing trend is observed from 1995 through present. These data improve our understanding of historic atmospheric deposition patterns and are being used to inform additional palaeolimnological research, including diatom analyses, with the broader objective of reconstructing historic nitrogen deposition and estimating critical loads for Sierra Nevada lakes.igure 1: SCP concentrations and accumulation rates from three Sierra Nevada Lake sediment cores (Moat, Pear, and Emerald Lakes).

An ecologic study comparing distribution of Pasteurella trehalosi and Mannheimia haemolytica between Sierra Nevada bighorn sheep, White Mountain bighorn sheep, and domestic sheep.

PubMed

Tomassini, Letizia; Gonzales, Ben; Weiser, Glen C; Sischo, William

2009-10-01

The prevalence and phenotypic variability of Pasteurella and Mannheimia isolates from Sierra Nevada bighorn sheep (Ovis canadensis sierrae), White Mountain bighorn sheep (Ovis canadensis nelsoni), and domestic sheep (Ovis aries) from California, USA, were compared. The White Mountain bighorn sheep population had a recent history of pneumonia-associated mortality, whereas the Sierra Nevada bighorn sheep population had no recent history of pneumonia-associated mortality. The domestic sheep flocks were pastured in areas geographically near both populations but were not known to have direct contact with either bighorn sheep population. Oropharyngeal swab samples were collected from healthy domestic and bighorn sheep and cultured to characterize bacterial species, hemolysis, biogroups, and biovariants. Pasteurella trehalosi and Mannheimia haemolytica were detected in all of the study populations, but the relative proportion of each bacterial species differed among sheep populations. Pasteurella trehalosi was more common than M. haemolytica in the bighorn sheep populations, whereas the opposite was true in domestic sheep. Mannheimia haemolytica was separated into 11 biogroups, and P. trehalosi was characterized into two biogroups. Biogroup distributions for M. haemolytica and P. trehalosi differed among the three populations; however, no difference was detected for the distribution of P. trehalosi biogroups between the Sierra Nevada bighorn sheep and domestic sheep. The prevalence odds ratios (pOR) for the distribution of M. haemolytica biogroups suggested little difference between White Mountain bighorn sheep and domestic sheep compared with Sierra Nevada bighorn sheep and domestic sheep, although these comparisons had relatively large confidence intervals for the point estimates. Hemolytic activity of the isolates was not different among the sheep populations for M. haemolytica but was different for P. trehalosi. No clear evidence of association was found in the Pasteurellaceae distribution between the White Mountains bighorn sheep and domestic sheep.

Thermochronological constraints on the Cambrian to recent geological evolution of the Argentina passive continental margin

NASA Astrophysics Data System (ADS)

Kollenz, Sebastian; Glasmacher, Ulrich A.; Rossello, Eduardo A.; Stockli, Daniel F.; Schad, Sabrina; Pereyra, Ricardo E.

2017-10-01

Passive continental margins are geo-archives that store information from the interplay of endogenous and exogenous forces related to continental rifting, post-breakup history, and climate changes. The recent South Atlantic passive continental margins (SAPCMs) in Brazil, Namibia, and South Africa are partly high-elevated margins ( 2000 m a.s.l.), and the recent N-S-trending SAPCM in Argentina and Uruguay is of low elevation. In Argentina, an exception in elevation is arising from the higher topography (> 1000 m a.s.l.) of the two NW-SE-trending mountain ranges Sierras Septentrionales and Sierras Australes. Precambrian metamorphic and intrusive rocks, and siliciclastic rocks of Ordovician to Permian age represent the geological evolution of both areas. The Sierras Australes have been deformed and metamorphosed (incipient - greenschist) during the Gondwanides Orogeny. The low-temperature thermochronological (LTT) data (< 240 °C) indicated that the Upper Jurassic to Lower Cretaceous opening of the South Atlantic has not completely thermally reset the surface rocks. The LTT archives apatite and zircon still revealed information on the pre- to post-orogenic history of the Gondwanides and the Mesozoic and Cenozoic South Atlantic geological evolution. Upper Carboniferous zircon (U-Th/He)-ages (ZHe) indicate the earliest cooling below 180 °C/1 Ma. Most of the ZHe-ages are of Upper Triassic to Jurassic age. The apatite fission-track ages (AFT) of Sierras Septentrionales and the eastern part of Sierras Australes indicate the South Atlantic rifting and, thereafter. AFT-ages of Middle to Upper Triassic on the western side of the Sierras Australes are in contrast, indicating a Triassic exhumation caused by the eastward thrusting along the Sauce Grande wrench. The corresponding t-T models report a complex subsidence and exhumation history with variable rates since the Ordovician. Based on the LTT-data and the numerical modelling we assume that the NW-SE-trending mountain ranges received their geographic NW-SE orientation during the syn- to post-orogenic history of the Gondwanides.

Spatiotemporal Patterns of Fault Slip Rates Across the Central Sierra Nevada Frontal Fault Zone

NASA Astrophysics Data System (ADS)

Rood, D. H.; Burbank, D.; Finkel, R. C.

2010-12-01

We examine patterns in fault slip rates through time and space across the transition from the Sierra Nevada to the Eastern California Shear Zone-Walker Lane belt. At each of four sites along the eastern Sierra Nevada frontal fault zone between 38-39° N latitude, geomorphic markers, such as glacial moraines and outwash terraces, are displaced by a suite of range-front normal faults. Using geomorphic mapping, surveying, and Be-10 surface exposure dating, we define mean fault slip rates, and by utilizing markers of different ages (generally, ~20 ka and ~150 ka), we examine rates through time and interactions among multiple faults over 10-100 ky timescales. At each site for which data are available for the last ~150 ky, mean slip rates across the Sierra Nevada frontal fault zone have probably not varied by more than a factor of two over time spans equal to half of the total time interval (~20 ky and ~150 ky timescales): 0.3 ± 0.1 mm/yr (mode and 95% CI) at both Buckeye Creek in the Bridgeport basin and Sonora Junction; and 0.4 +0.3/-0.1 mm/yr along the West Fork of the Carson River at Woodfords. Our data permit that rates are relatively constant over the time scales examined. In contrast, slip rates are highly variable in space over the last ~20 ky. Slip rates decrease by a factor of 3-5 northward over a distance of ~20 km between the northern Mono Basin (1.3 +0.6/-0.3 mm/yr at Lundy Canyon site) and the Bridgeport Basin (0.3 ± 0.1 mm/yr). The 3-fold decrease in the slip rate on the Sierra Nevada frontal fault zone northward from Mono Basin reflects a change in the character of faulting north of the Mina Deflection as extension is transferred eastward onto normal faults between the Sierra Nevada and Walker Lane belt. A compilation of regional deformation rates reveal that the spatial pattern of extension rates changes along strike of the Eastern California Shear Zone-Walker Lane belt. South of the Mina Deflection, extension is accommodated within a diffuse zone of normal and oblique faults, with extension rates increasing northward on the Fish Lake Valley fault. Where faults of the Eastern California Shear Zone terminate northward into the Mina Deflection, extension rates increase northward along the Sierra Nevada frontal fault zone to ~0.7 mm/yr in northern Mono Basin. This spatial pattern suggests that extension is transferred from faults systems to the east (e.g. Fish Lake Valley fault) and localized on the Sierra Nevada frontal fault zone as Eastern California Shear Zone-Walker Lane belt faulting is transferred through the Mina Deflection.

77 FR 49862 - Santa Cruz and Monterey Bay Railway Company-Assignment of Lease Exemption-Union Pacific Railroad...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-17

... Monterey Bay Railway Company--Assignment of Lease Exemption--Union Pacific Railroad Company and Sierra Northern Railway Santa Cruz and Monterey Bay Railway Company (SCMB), a noncarrier, has filed a verified notice of exemption under 49 CFR 1150.31 to acquire by assignment from Sierra Northern Railway its lease...

Characteristics of Adolescent Sierra Leonean Refugees in Public Schools in New York City

ERIC Educational Resources Information Center

Davies, Amy Z.

2008-01-01

The tendency to view immigrant students as a monolithic group has masked the needs of specific groups of students. This study gives visibility to Sierra Leonean refugee students and indicates to policy makers, administrators, and teachers provisions that would facilitate the students' integration into the school system in the United States. The…

Chapter 15: A desired future condition for Sierra Nevada Forests

Treesearch

M. North

2012-01-01

An unexpected outcome of U.S. Forest Service General Technical Report PSW-GTR 220, "An Ecosystem Management Strategy for Sierran Mixed-Conifer Forests" (North et al. 2009), was how it generated discussion about a desired future condition for Sierra Nevada forests. The paper did not convey leading-edge research results or provide an exhaustive literature...

Ozone distribution in remote ecologically vulnerable terrain of the southern Sierra Nevada, CA

Treesearch

Jeanne Panek; David Saah; Annie Esperanza; Andrzej Bytnerowicz; Witold Fraczek; Ricardo Cisneros

2013-01-01

Ozone concentration spatial patterns remain largely uncharacterized across the extensive wilderness areas of the Sierra Nevada, CA, despite being downwind of major pollution sources. These natural areas, including four national parks and four national forests, contain forest species that are susceptible to ozone injury. Forests stressed by ozone are also more...

Constraints on mechanized treatment significantly limit mechanical fuels reduction extent in the Sierra Nevada

Treesearch

Malcolm P. North; April Brough; Jonathan W. Long; Brandon M. Collins; Phil Bowden; Don Yasuda; Jay Miller; Neil Suighara

2015-01-01

With air quality, liability, and safety concerns, prescribed burning and managed wildfire are often considered impractical treatments for extensive fuels reduction in western US forests. For California's Sierra Nevada forests, we evaluated the alternative and analyzed the amount and distribution of constraints on mechanical fuels treatments on USDA Forest Service...

Habitat modeling and movements of the Yosemite toad (Anaxyrus (=Bufo) canorus) in the Sierra Nevada, California

Treesearch

C.T. Liang

2010-01-01

The Yosemite toad (Anaxyrus (=Bufo) canorus) is a high-elevation species endemic to the Sierra Nevada mountain range in California and is part of the world-wide amphibian declines phenomenon. The toad is thought to have disappeared from over 50% of its historic range even in seemingly undisturbed areas, and...

The status and conservation of mesocarnivores in the Sierra Nevada

Treesearch

William J. Zielinski

2004-01-01

Carnivores play important roles in structuring communities, and their populations are useful indicators of ecosystem condition (Wennergren and others 1995, Buskirk 1999, Crooks and Soulé 1999, Terborgh and others 2001). As many as 4 of 20 native mammalian carnivore species have been extirpated from the southern Cascade Mountains and Sierra Nevada, with unmeasured...

Chapter 12: The variable-density thinning study at Stanislaus-Tuolumne Experimental Forest

Treesearch

E. Knapp; M. North; M. Benech; B. Estes

2012-01-01

Prior to historical logging and fire suppression, forests of the Sierra Nevada were extremely heterogeneous. Frequent low- to moderate-intensity fire was partly responsible for this heterogeneity, which in turn helped make forests resilient to high-severity stand-replacing events. Early observers of forests on the west slope of the Sierra Nevada noted the...

Oak management by county jurisdictions in the central Sierra Nevada, California

Treesearch

Richard R. Harris; Susan D. Kocher

2002-01-01

We evaluated county planning policies and procedures to determine what protection is provided to oak woodlands during the land development process. We selected three Sierra Nevada counties to do a pilot assessment: El Dorado, Placer and Madera. The assessment methodology included three components: 1) analysis of county plans, policies, guidelines, and ordinances to...

Factors influencing the scarification and germination of three montane Sierra Nevada shrubs

Treesearch

J. Boone Kaufmann; R. E. Martin

1991-01-01

Following fires in the forested ecosystems of the northern Sierra Nevada, California, early successional communities are often dominated by shrubs that arise from seeds that have remained viable in soil seedbanks for long periods. The germination response of seeds of three seral montane shrub species was investigated following exposure to differing types of heat (wet...

Flying High With Civil Air Patrol: The Sierra Blanca Civil Air Patrol Squadron.

ERIC Educational Resources Information Center

Carnicom, Gene E.

The Sierra Blanca Civil Air Patrol (CAP) Cadet Squadron from Mescalero, New Mexico, is a program funded by the tribe and the state of New Mexico for Mescalero Apache youth. The national CAP Cadet Program promotes moral leadership, aerospace education, leadership, and physical fitness; Mescalero cadets have learned self-confidence and leadership…

Diets of California spotted owls in the Sierra National Forest

Treesearch

Thomas E. Munton; Kenneth D. Johnson; George N. Steger; Gary P. Eberlein

2002-01-01

From May 1987 through October 1992 and from July through August 1998, we studied diets of California spotted owls (Strix occidentalis occidentalis). Regurgitated pellets were collected at roost and nest sites between 1,000 and 7,600 ft elevation in the Sierra National Forest and were examined for remnant bones, feathers, and insect exoskeletons....

Response of Sierra Nevada vegetation and fire regimes to past climate changes

Treesearch

R. Scott Anderson

2004-01-01

The study of changing vegetation patterns within forested communities of the Sierra Nevada has had a long history, initiated by the great naturalist John Muir. More recently, paleoecologists, who study ecosystems of the past, have analyzed fossil plant remains recovered from lake and meadow sediments to understand the regional biogeography and disturbance history of...

Trajectories of Internalizing Problems in War-Affected Sierra Leonean Youth: Examining Conflict and Postconflict Factors

ERIC Educational Resources Information Center

Betancourt, Theresa S.; McBain, Ryan; Newnham, Elizabeth A.; Brennan, Robert T.

2013-01-01

Three waves of data from a prospective longitudinal study in Sierra Leone were used to examine internalizing trajectories in 529 war-affected youth (ages 10-17 at baseline; 25% female). Latent class growth analyses identified 4 trajectories: A large majority of youth maintained lower levels of internalizing problems (41.4%) or significantly…

75 FR 76975 - 2015 Resource Pool-Sierra Nevada Region

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-10

...The Western Area Power Administration (Western), a Federal power marketing administration of DOE, announces the Final 2015 Resource Pool allocations pursuant to its 2004 Power Marketing Plan (Marketing Plan) for the Sierra Nevada Customer Service Region (SNR). This notice includes a summary of the comments received on Western's proposed 2015 Resource Pool allocations and Western's responses.

Interactions between western gall rust and its Pinus hosts, P. jeffreyi and P. contorta, in Sierra De San Pedro Martir National Park, Northern Baja California, Mexico

Treesearch

Detlev R. Vogler; Brian W. Geils

2008-01-01

The Sierra de San Pedro Martir is a mountain range in north-central Baja that comprises the southern-most extension of the Californian coniferous flora, including Pinus jeffreyi, P. contorta, P. lambertiana, Abies concolor, and Calocedrus decurrens. These forests are similar...

Using epiphytic macrolichen communities for biomonitoring ammonia in forests of the greater Sierra Nevada, California

Treesearch

Sarah Jovan; Bruce Mccune

2006-01-01

Chronic, excessive nitrogen deposition is potentially an important ecological threat to forests of the greater Sierra Nevada in California. We developed a model for ammonia bioindication, a major nitrogen pollutant in the region, using epiphytic macrolichens. We used non-metric multidimensional scaling to extract gradients in lichen community composition from surveys...

Roadless area-intensive management tradeoffs on the Sierra National Forest, California

Treesearch

Robert J. Hrubes; Kent P. Connaughton; Robert W. Sassaman

1979-01-01

This hypothesis was tested by a linear programing model: Roadless areas on the Sierra National Forest precluded from planned future development would be candidates for wilderness designation, and the associated loss in present and future timber harvests could be offset by investing in more intensive management. The results of this simulation test suggest that levels of...

Ozone, nitric acid, and ammonia air pollution is unhealthy for people and ecosystems in southern Sierra Nevada, California

Treesearch

R. Cisneros; A. Bytnerowicz; D. Schweizer; S. Zhong; S. Traina; D.H. Bennett

2010-01-01

Two-week average concentrations of ozone (O3), nitric acid vapor (HNO3) and ammonia (NH3) were measured with passive samplers during the 2002 summer season across the central Sierra Nevada Mountains, California, along the San Joaquin River drainage. Elevated concentrations of the pollutants were...

Situation Report--Australia, Burundi, Cambodia, Mexico, Montserrat, Nicaragua, Papua & New Guinea, Republic of Vietnam, Sabah, Sarawak, Sierra Leone, Tahiti, Tonga.

ERIC Educational Resources Information Center

International Planned Parenthood Federation, London (England).

Data relating to population and family planning in fourteen foreign countries are presented in these situation reports. Countries included are Australia, Burundi, Cambodia, Mexico, Montserrat, Nicaragua, Papua and New Guines, Republic of Vietnam, Sabah, Sarawak, Sierra Leone, Tahiti (French Polynesia), and Tonga. Information is provided under two…

Situation Report--Algeria, Bangladesh, Fiji, Gilbert and Ellice Islands, Iran, Jordan, New Zealand, Rwanda, and Sierra Leone.

ERIC Educational Resources Information Center

International Planned Parenthood Federation, London (England).

Data relating to population and family planning in nine foreign countries are presented in these situation reports. Countries included are Algeria, Bangledesh, Fiji, Gilbert and Ellice Islands, Iran, Jordan, New Zealand, Rwanda, and Sierra Leone. Information is provided under two topics, general background and family planning situation, where…

Multi-scale evaluation of the environmental controls on burn probability in a southern Sierra Nevada landscape

Treesearch

Sean A. Parks; Marc-Andre Parisien; Carol Miller

2011-01-01

We examined the scale-dependent relationship between spatial fire likelihood or burn probability (BP) and some key environmental controls in the southern Sierra Nevada, California, USA. Continuous BP estimates were generated using a fire simulation model. The correspondence between BP (dependent variable) and elevation, ignition density, fuels and aspect was evaluated...

Socio-Ecological Factors Affecting Pregnant Women's Anemia Status in Freetown, Sierra Leone

ERIC Educational Resources Information Center

M'Cormack, Fredanna; Drolet, Judy

2012-01-01

Background: Sierra Leone has high maternal mortality. Socio-ecological factors are considered contributing factors to this high mortality. Anemia is considered to be a direct cause of 4% of maternal deaths and an indirect cause of 20-40% of maternal deaths. Purpose: The current study explores socio-ecological contributing factors to the anemia…

What Is Shakespeare Doing in My Hut?: A-Level Literature and the Sierra Leonean Student.

ERIC Educational Resources Information Center

Wright, Handel K.

A study brought together literature appreciation, schema theory, and cross-cultural studies to explore the relationship between the backgrounds of students in one sixth-form literature class in Sierra Leone and the contexts of the plays described in the drama section of the "A" level literature syllabus of the West African Examinations…

Thermal regimes and snowpack relations of periglacial talus slopes, Sierra Nevada, California, USA.

Treesearch

Constance I Millar; Robert D. Westfall; Diane L. Delany

2014-01-01

Thermal regimes of eight periglacial talus slopes, at contrasting elevations, aspects, and substrates, in the Sierra Nevada, California, had complex microclimatic patterns partially decoupled from external conditions. Over three years, warm seasons showed mean talus matrix temperatures and daily variances lower than surfaces and cooler than free-air; talus surface and...

Population dynamics of the California spotted owl in the Sierra Nevada, California

Treesearch

J.A. Blakesley; M.E. Seamans; M.M. Connor; A.B. Franklin; G.C. White; R.J. Gutierrez; J.E. Hines; J.D. Nichols; T.E. Munton; D.W.H. Shaw; J.J. Keane; G.N. Steger; T.L. McDonald

2010-01-01

The California spotted owl (Strix occidentalis occidentalis) is the only spotted owl subspecies not listed as threatened or endangered under the United States Endangered Species Act despite petitions to list it as threatened. We conducted a meta-analysis of population data for 4 populations in the southern Cascades and Sierra Nevada, California,...

Stability and change in minerotrophic peatlands, Sierra Nevada of California and Nevada

Treesearch

James W. Bartolome; Don C. Erman; Charles F. Schwara

1990-01-01

Minerotrophic peatlands or fens in California's Sierra Nevada are small wet meadows surrounded by mixed conifer forest. The dynamics of vegetation change at the meadow edge and the ages and development of fens were investigated, in the Sagehen Creek Basin near Truckee, California, through the use of radiocarbon dating of peat, pollen studies, examination of...

The Violence of Peace and the Role of Education: Insights from Sierra Leone

ERIC Educational Resources Information Center

Novelli, Mario; Higgins, Sean

2017-01-01

Research on peacebuilding has mushroomed over the last decade and there is a growing interest in the role of education in supporting peacebuilding processes. This paper engages with these debates, UN peacebuilding activities and the location of education initiatives therein, through a case study of Sierra Leone. In the first part, we explore the…

Aspen in the Sierra Nevada: Regional conservation of a continental species

Treesearch

Paul C. Rogers; Wayne D. Shepperd; Dale L. Bartos

2007-01-01

Quaking aspen (Populus tremuloides Michx.) a common species in North America, is a minor species in the Sierra Nevada of California. However, the limited coverage of aspen in this area appears to carry a disproportionate biodiversity load: numerous species are dependent on the unique components of aspen forests habitat. Land managers in the region...

78 FR 24515 - Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Sierra...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-25

... Service 50 CFR Part 17 Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for... Threatened Wildlife and Plants; Designation of Critical Habitat for the Sierra Nevada Yellow-Legged Frog, the... that the designation of critical habitat is not prudent. (2) Specific information on: (a) The amount...

Chapter 8: Using GTR 220 to build stakeholder collaboration

Treesearch

C. Thomas

2012-01-01

Since 2008, Sierra Forest Legacy, a nonprofit conservation organization, has increased its participation in the design of projects on national forest lands in the Sierra Nevada. Our interest has been to engage scientists, managers, and other stakeholders in the design of projects that integrate the best available scientific information. Our second interest has been to...

From Literacy Activities to Entrepreneurship in Siete Pilas. Chapter 6.

ERIC Educational Resources Information Center

Chacon, Antonio; Polo, Angel

This chapter describes a community development project in Siete Pilas (Spain), a village whose economy is based primarily on small family farms and unskilled labor. The project grew out of the Sierra Education Program, which in 1980 sent adult-education teachers to five villages in the Sierra de Ronda region. The goal was to stimulate a socially…

Reconstruction versus Transformation: Post-War Education and the Struggle for Gender Equity in Sierra Leone

ERIC Educational Resources Information Center

Maclure, Richard; Denov, Myriam

2009-01-01

In post-war contexts, education is widely regarded as essential not only for civic reconciliation, but also as a key force for gender equity. In Sierra Leone, however, despite enhanced educational opportunities for girls, much of the emphasis on post-war educational reconstruction is unlikely to rectify gender inequities that remain entrenched…

School Persistence in the Wake of War: Wartime Experiences, Reintegration Supports, and Dropout in Sierra Leone

ERIC Educational Resources Information Center

Zuilkowski, Stephanie Simmons; Betancourt, Theresa S.

2014-01-01

This article examines the relationship of wartime experience and reintegration supports to students' risk of school dropout. It draws on longitudinal, mixed-methods data collected among children and youth in Sierra Leone from 2002 through 2008. The study finds that family financial support and perceived social support are positively associated…

A multi-scale evaluation of pack stack effects on subalpine meadow plant communities in the Sierra Nevada

USDA-ARS?s Scientific Manuscript database

We evaluated the influence of pack stock (i.e., horse and mule) use on meadow plant communities in Sequoia and Yosemite National Parks in the Sierra Nevada mountains of California. Meadows were sampled to account for inherent variability across multiple scales by: 1) controlling for among-meadow var...

Two new species of Chloroperlidae (Plecoptera) from California

Treesearch

R. W. Baumann; R. L. Bottorff

1997-01-01

Abstract - Suwallia sierra and Sweltsa pisteri are described as new species in the family Chloroperlidae from California, USA. Illustrations of the male terminalia of both species and the female and egg of S. sierra are presented. In addition, detailed figures of the epiproct of 2 similar species, Sweltsa townesi and Sweltsa resima, are included. Diagnoses are...

Lessons learned from prescribed fire in ponderosa pine forests of the southern Sierra Nevada

Treesearch

Karen E. Bagne; Kathryn L. Purcell

2009-01-01

Prescribed fire is a commonly used management tool in fire-suppressed ponderosa pine (Pinus ponderosa) forests, but effects of these fires on birds are largely unstudied. We investigated both direct and indirect impacts on breeding birds in ponderosa pine forests of the southern Sierra Nevada where fires were applied in the spring. Following...

Estimating trend in occupancy for the Southern Sierra fisher Martes pennanti population

Treesearch

William J. Zielinski; James A. Baldwin; Richard L. Truex; Jody M. Tucker; Patricia A. Flebbe

2013-01-01

Carnivores are important elements of biodiversity, not only because of their role in transferring energy and nutrients, but also because they influence the structure of the communities where they occur. The fisher Martes pennanti is amammalian carnivore that is associated with late-successional mixed forests in the Sierra Nevada in California, and...

Nutrient fluxes in forests of the eastern Sierra Nevada: comparisons with humid forest systems

Treesearch

Dale W. Johnson; Richard B. Susfalk; Randy A. Dahlgreen; Virginia Boucher; Andrzej Bytnerowicz

1998-01-01

Preliminary results of studies on nutrient fluxes in forests of the eastern Sierra Nevada were compared to those from more humid and polluted ecosystems. Snowmelt, soil solution, soil, and streamwater were collected from Jeffrey and lodgepole pine (Pinus jeffreyii [Grev. and Balf.] and Pinus contorta Dougl.) stands in Little Valley...

A Grammar of Sierra Popoluca (Soteapanec, a Mixe-Zoquean Language)

ERIC Educational Resources Information Center

de Jong Boudreault, Lynda J.

2009-01-01

This dissertation is a comprehensive description of the grammar of Sierra Popoluca (SP, aka Soteapanec), a Mixe-Zoquean language spoken by approximately 28,000 people in Veracruz, Mexico. This grammar begins with an introduction to the language, its language family, a typological overview of the language, a brief history of my fieldwork, and the…

Silviculture-ecology of forest-zone hardwoods in the Sierra Nevada

Treesearch

Philip M. McDonald; John C. Tappeiner

1996-01-01

Although the principal hardwood species in the forest zone of the Sierra Nevada (California black oak, tanoak, Pacific madrone, and canyon live oak) are key components of many ecosystems, they have received comparatively little study. Currently they are underutilized and unmanaged. This paper brings together what is known on the silviculture-ecology of these species...

Nesting habitat of Warbling Vireos across an elevational gradient in the southern Sierra Nevada

Treesearch

Kathryn Purcell

2007-01-01

Populations of Warbling Vireos (Vireo gilvus) are declining in California, apparently due to low reproductive success. From 1989—2002, I studied the nest-site selection and reproductive success ofWarbling Vireos across an elevational gradient in the southern Sierra Nevada. Warbling Vireos regularly nested in upland coniferous forests with...

Thinning – a tool for restoration of California's Southern Sierra Nevada blue oak woodlands

Treesearch

Richard B. Standiford; Ralph L. Phillips; Neil K. McDougald

2015-01-01

Fire frequency on a blue oak (Quercus douglasii) dominated rangeland in California's southern Sierra Nevada foothills was approximately every 10 years until 1965, followed by a 30 year period of fire exclusion. This resulted in a dense tree overstory with small diameters, high crown cover, poor acorn and forage production, and limited...

Using the MicroASAR on the NASA SIERRA UAS in the Characterization of Arctic Sea Ice Experiment

DTIC Science & Technology

2010-05-01

such that the dechirped signal is at an intermediate frequency. Feedthrough rejection is done by a surface acoustic wave (SAW) filter with its first...Fig. 3. NASA SIERRA UAS 3-View and Specifications • Up-looking and down-looking shortwave spectrometers. • Down-looking temperature sensors ( pyrometers

Current investigations of fungal ectomycorrhizal communities in the Sierra Nevada Forest

Treesearch

Thomas D. Bruns; Annette M. Kretzer; Thomas R. Horton; Eric A-D. Stendell; Martin I. Bidartondo; Timothy M. Szaro

2002-01-01

Progress on two main studies on fungal ectomycorrhizal communities in the Sierra National Forest is discussed. One study examined the short-term effects of ground fire on the ectomycorrhizal community and the other examined the ectomycorrhizal associates of snow plant (Sarcodes sanguinea). In the ground-fire study we found that a large initial...

Friends of the Inyo: Eastern Sierra Wilderness Stewardship Project

Treesearch

Paul McFarland; Jamie Anderson

2007-01-01

Friends of the Inyo is a non-profit, conservation organization dedicated to preserving public lands and wildlife of the Eastern Sierra. First founded in 1986, Friends of the Inyo hired its first staff person in 2000. Today, the organization enjoys a vibrant and growing membership of 500 individuals and employs three people-Executive Director, Paul McFarland (the...

SURVEY OF LIBRARY PERSONNEL IN SIERRA COLLEGE EMPLOYMENT AREA.

ERIC Educational Resources Information Center

YOUNG, ELMA L.

FOR TWO YEARS PRIOR TO THIS STUDY, SIERRA COLLEGE, CALIFORNIA, HAD OFFERED LIBRARY TECHNICIAN TRAINING IN ITS EVENING PROGRAM. A SURVEY OF LIBRARIES IN THE 5-COUNTY EMPLOYMENT AREA OF THE COLLEGE'S GRADUATES WAS MADE IN 1968 TO DETERMINE NEEDS FOR LIBRARY TECHNICIANS. IN THE FIVE COUNTIES, 167 LIBRARIES WERE IDENTIFIED, WITH A TOTAL OF 1084…

Nutrient Cycling in Managed and Unmanaged Oak Woodland-Grass Ecosystems

Treesearch

Randy Dahlgren; Michael J. Singer

1991-01-01

The influence of oak trees and grazing on nutrient cycling in oak woodland-grass ecosystems was examined at the Sierra Foothill Range Field Station in the northern-Sierra Nevada foothills of California. Nutrient concentrations in ecosystem waterflows (precipitation, canopy throughfall, and soil solutions) were monitored in a non-managed natural area and in an adjacent...

From Typology to Topography in Clarence King's "Mountaineering in the Sierra Nevada."

ERIC Educational Resources Information Center

Hoekzema, Loren

The book "Mountaineering in the Sierra Nevada" by Clarence King, a late-ninteenth-century American geologist, writer, art critic, and romantic, is discussed in this paper. In the writing and revision of this book, King was attempting a metamorphosis of landscape description into popular reading as he moved from being a symbolic writer to…

Comprehensive Yet Scalable Health Information Systems for Low Resource Settings: A Collaborative Effort in Sierra Leone

PubMed Central

Braa, Jørn; Kanter, Andrew S.; Lesh, Neal; Crichton, Ryan; Jolliffe, Bob; Sæbø, Johan; Kossi, Edem; Seebregts, Christopher J.

2010-01-01

We address the problem of how to integrate health information systems in low-income African countries in which technical infrastructure and human resources vary wildly within countries. We describe a set of tools to meet the needs of different service areas including managing aggregate indicators, patient level record systems, and mobile tools for community outreach. We present the case of Sierra Leone and use this case to motivate and illustrate an architecture that allows us to provide services at each level of the health system (national, regional, facility and community) and provide different configurations of the tools as appropriate for the individual area. Finally, we present a, collaborative implementation of this approach in Sierra Leone. PMID:21347003

A new species of earth snake (Dipsadidae, Geophis) from Mexico.

PubMed

Canseco-Márquez, Luis; Pavón-Vázquez, Carlos J; López-Luna, Marco Antonio; Nieto-Montes de Oca, Adrián

2016-01-01

A new species of the Geophis dubius group is described from the mountains of the Sierra Zongolica in west-central Veracruz and the Sierra de Quimixtlán in central-east Puebla. The new species is most similar to Geophis duellmani and Geophis turbidus, which are endemic to the mountains of northern Oaxaca and the Sierra Madre Oriental of Puebla and Hidalgo, respectively. However, the new species differs from Geophis duellmani by the presence of postocular and supraocular scales and from Geophis turbidus by having a bicolor dorsum. With the description of the new species, the species number in the genus increases to 50 and to 12 in the Geophis dubius group. Additionally, a key to the species of the Geophis dubius group is provided.

Status and understanding of groundwater quality in the Tahoe-Martis, Central Sierra, and Southern Sierra study units, 2006-2007--California GAMA Priority Basin Project

USGS Publications Warehouse

Fram, Miranda S.; Belitz, Kenneth

2012-01-01

Groundwater quality in the Tahoe-Martis, Central Sierra, and Southern Sierra study units was investigated as part of the Priority Basin Project of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program. The three study units are located in the Sierra Nevada region of California in parts of Nevada, Placer, El Dorado, Madera, Tulare, and Kern Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board, in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The project was designed to provide statistically robust assessments of untreated groundwater quality within the primary aquifer systems used for drinking water. The primary aquifer systems (hereinafter, primary aquifers) for each study unit are defined by the depth of the screened or open intervals of the wells listed in the California Department of Public Health (CDPH) database of wells used for municipal and community drinking-water supply. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifers; shallower groundwater may be more vulnerable to contamination from the surface. The assessments for the Tahoe-Martis, Central Sierra, and Southern Sierra study units were based on water-quality and ancillary data collected by the USGS from 132 wells in the three study units during 2006 and 2007 and water-quality data reported in the CDPH database. Two types of assessments were made: (1) status, assessment of the current quality of the groundwater resource, and (2) understanding, identification of the natural and human factors affecting groundwater quality. The assessments characterize untreated groundwater quality, not the quality of treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentrations divided by benchmark concentrations) were used for evaluating groundwater quality for those constituents that have Federal or California regulatory or non-regulatory benchmarks for drinking-water quality. A relative-concentration (RC) greater than (>) 1.0 indicates a concentration above a benchmark. RCs for organic constituents (volatile organic compounds and pesticides) and special-interest constituents were classified as "high" (RC > 1.0), "moderate" (1.0 ≥ RC > 0.1), or "low" (RC ≤ 0.1). For inorganic constituents (major ions, trace elements, nutrients, and radioactive constituents), the boundary between low and moderate RCs was set at 0.5. A new metric, aquifer-scale proportion, was used in the status assessment as the primary metric for evaluating regional-scale groundwater quality. High aquifer-scale proportion is defined as the percentage of the area of the primary aquifers with RC > 1.0 for a particular constituent or class of constituents; moderate and low aquifer-scale proportions are defined as the percentages of the area of the primary aquifer with moderate and low RCs, respectively. Percentages are based on an areal rather than a volumetric basis. Two statistical approaches—grid-based, which used one value per grid cell, and spatially weighted, which used multiple values per grid cell—were used to calculate aquifer-scale proportions for individual constituents and classes of constituents. The spatially weighted estimates of high aquifer-scale proportions were within the 90-percent (%) confidence intervals of the grid-based estimates in all cases. The status assessment showed that inorganic constituents had greater high and moderate aquifer-scale proportions than did organic constituents in all three study units. In the Tahoe-Martis study unit, RCs for inorganic constituents with health-based benchmarks (primarily arsenic) were high in 20% of the primary aquifer, moderate in 13%, and low in 67%. In the Central Sierra study unit, aquifer-scale proportions for inorganic constituents with health-based benchmarks (primarily arsenic, uranium, fluoride, and molybdenum) were 41% high, 36% moderate, and 23% low. In the Southern Sierra study unit, 32, 34, and 34% of the primary aquifer had high, moderate, and low RCs of inorganic constituents with health-based benchmarks (primarily arsenic, uranium, fluoride, boron, and nitrate). The high aquifer-scale proportions for inorganic constituents with non-health-based benchmarks were 14, 34, and 24% for the Tahoe-Martis, Central Sierra, and Southern Sierra study units, respectively, and the primary constituent was manganese for all three study units. Organic constituents with health-based benchmarks were not present at high RCs in the primary aquifers of the Central Sierra and Southern Sierra study units, and were present at high RCs in only 1% of the Tahoe-Martis study unit. Moderate aquifer-scale proportions for organic constituents were 10%: the trihalomethane chloroform in the Tahoe-Martis study unit; chloroform and the herbicide simazine in the Central Sierra study unit; and chloroform, simazine, the herbicide atrazine, and the solvent perchloroethene in the Southern Sierra study unit. The second component of this study, the understanding assessment, identified the natural and human factors that may have affected groundwater quality in the three study units by evaluating statistical correlations between water-quality constituents and potential explanatory factors. The potential explanatory factors evaluated were land use, septic tank density, climate, relative position in the regional flow system, aquifer lithology, geographic location, well depth and depth to the top of the screened or open interval in the well, groundwater age distribution, pH, and dissolved oxygen concentration. Results of the statistical evaluations were used to explain the occurrence and distribution of constituents in the study units. Aquifer lithology (granitic, metamorphic, sedimentary, or volcanic rocks), groundwater age distribution [modern (recharged since 1952), pre-modern (recharged before 1952), or mixed (containing both modern and pre-modern recharge)], geographic location, pH, and dissolved oxygen were the most significant factors explaining the occurrence patterns of most inorganic constituents. High and moderate RCs of arsenic were associated with pre-modern and mixed-age groundwater and two distinct sets of geochemical conditions: (1) oxic, high-pH conditions, particularly in volcanic rocks, and (2) low-oxygen to anoxic conditions and low- to neutral-pH conditions, particularly in granitic rocks. In granitic and metamorphic rocks, high and moderate RCs of uranium were associated with pre-modern and mixed-age groundwater, low-oxygen to anoxic conditions, and location within parts of the Central Sierra and Southern Sierra study units known to have rocks with anomalously high uranium content compared to other parts of the Sierra Nevada. High and moderate RCs of uranium in sedimentary rocks were associated with pre-modern-age groundwater, oxic and high-pH conditions, and location in the Tahoe Valley South subbasin within the Tahoe-Martis study unit. Land use within 500 meters of the well and groundwater age were the most significant factors explaining occurrence patterns of organic constituents. Herbicide detections were most strongly associated with modern- and mixed-age groundwater from wells with agricultural land use. Trihalomethane detections were most strongly associated with modern- and mixed-age groundwater from wells with > 10% urban land use and (or) septic tank density > 7 tanks per square kilometer. Solvent detections were not significantly related to groundwater age. Eighty-three percent of the wells with modern- or mixed-age groundwater, and 86% of wells with detections of herbicides and (or) THMs had depths to the top of the screened or open interval of 5% agricultural land use and detection of a herbicide or solvent had the highest nitrate concentrations. Comparison between observed and predicted detection frequencies of perchlorate suggests that the perchlorate detected at concentrations < 1 microgram per liter likely reflects the distribution of perchlorate under natural conditions, and that the perchlorate detected at higher concentrations may reflect redistribution of originally natural perchlorate salts by irrigation in the agricultural areas of the Southern Sierra study unit.

Transmission dynamics of Ebola virus disease and intervention effectiveness in Sierra Leone

PubMed Central

Fang, Li-Qun; Yang, Yang; Jiang, Jia-Fu; Yao, Hong-Wu; Kargbo, David; Li, Xin-Lou; Jiang, Bao-Gui; Kargbo, Brima; Tong, Yi-Gang; Wang, Ya-Wei; Liu, Kun; Kamara, Abdul; Dafae, Foday; Kanu, Alex; Jiang, Rui-Ruo; Sun, Ye; Sun, Ruo-Xi; Chen, Wan-Jun; Ma, Mai-Juan; Dean, Natalie E.; Thomas, Harold; Longini, Ira M.; Halloran, M. Elizabeth; Cao, Wu-Chun

2016-01-01

Sierra Leone is the most severely affected country by an unprecedented outbreak of Ebola virus disease (EVD) in West Africa. Although successfully contained, the transmission dynamics of EVD and the impact of interventions in the country remain unclear. We established a database of confirmed and suspected EVD cases from May 2014 to September 2015 in Sierra Leone and mapped the spatiotemporal distribution of cases at the chiefdom level. A Poisson transmission model revealed that the transmissibility at the chiefdom level, estimated as the average number of secondary infections caused by a patient per week, was reduced by 43% [95% confidence interval (CI): 30%, 52%] after October 2014, when the strategic plan of the United Nations Mission for Emergency Ebola Response was initiated, and by 65% (95% CI: 57%, 71%) after the end of December 2014, when 100% case isolation and safe burials were essentially achieved, both compared with before October 2014. Population density, proximity to Ebola treatment centers, cropland coverage, and atmospheric temperature were associated with EVD transmission. The household secondary attack rate (SAR) was estimated to be 0.059 (95% CI: 0.050, 0.070) for the overall outbreak. The household SAR was reduced by 82%, from 0.093 to 0.017, after the nationwide campaign to achieve 100% case isolation and safe burials had been conducted. This study provides a complete overview of the transmission dynamics of the 2014−2015 EVD outbreak in Sierra Leone at both chiefdom and household levels. The interventions implemented in Sierra Leone seem effective in containing the epidemic, particularly in interrupting household transmission. PMID:27035948

Wetland occupancy of pond-breeding amphibians in Yosemite National Park, USA

USGS Publications Warehouse

Fellers, Gary M.; Kleeman, Patrick M.; Miller, David A.W.

2015-01-01

We estimated wetland occupancy and population trends for three species of pond-breeding anurans in Yosemite National Park from 2007-2011. We used a double survey technique in which two observers independently surveyed each site on the same day. Double surveys allowed us to calculate detectability for the three most common anurans within the park: Rana sierrae, Anaxyrus canorus, and Pseudacris regilla. Annual estimates of detectability were generally high; mean detectability ranged from 73.7% + 0.6 (SE) for any life history stage of A. canorus to 86.7% + 0.7 for sites with P. regilla reproduction (eggs or larvae present). Detectability was most variable for Anaxyrus canorus, which ranged from 45.9% to 99.7%. The probability of occupancy for R. sierrae was highest in larger, low-elevation wetlands that lacked fish. Anaxyrus canorus were more common in shallow high-elevation ponds; their occurrence was minimally impacted by the presence of fish. Finally, occurrence of P. regilla was largely unrelated to wetland size and elevation, but like R. sierrae, they were less likely to occupy sites with fi sh. Occupancy showed no trend over the five years of our study for R. sierrae or A. canorus when considering either sites with any life stage or only sites with reproduction. However, P. regilla showed a modest downward trend for sites with any life stage and sites with reproduction. Our results for R. sierrae run counter to expectations given recent concern about the decline of this species, while our findings for P. regilla raise concerns for this widespread and generally common species.

Rapid assessment of knowledge, attitudes, practices, and risk perception related to the prevention and control of Ebola virus disease in three communities of Sierra Leone.

PubMed

Jiang, Hai; Shi, Guo-Qing; Tu, Wen-Xiao; Zheng, Can-Jun; Lai, Xue-Hui; Li, Xin-Xu; Wei, Qiang; Li, Mei; Deng, Li-Quan; Huo, Xiang; Chen, Ming-Quan; Xu, Feng; Ye, Long-Jie; Bai, Xi-Chen; Chen, Tong-Nian; Yin, Shao-Hua; Samba, Thomas T; Liang, Xiao-Feng

2016-06-06

The recent outbreak of the Ebola virus disease (EVD) in Sierra Leone has been characterized by the World Health Organization as one of the most challenging EVD outbreaks to date. The first confirmed case in Sierra Leone was a young woman who was admitted to a government hospital in Kenema following a miscarriage on 24 May 2014. On 5 January 2015, intensified training for an EVD response project was initiated at the medical university of Sierra Leone in Jui. To understand the knowledge, attitudes, practices, and perceived risk of EVD among the public, especially after this training, a rapid assessment was conducted from 10 to 16 March 2015. Interviews were conducted with 466 participants based on questionnaires that were distributed from 10 to 16 March 2015 by cluster sampling in three adjacent communities, namely Jui, Grafton, and Kossoh Town, in the Western Area Rural District of Sierra Leone. It was found that knowledge about EVD was comprehensive and high. Positive attitude towards prevention was found to be satisfactory. Nearly all participants knew the reporting phone number 117 and had reported some change in behavior since learning about Ebola. More than half (62 %) of the participants had a history of travelling to urban areas, which increases the risk of infection. The multivariable logistic regression analysis showed that community and occupation were variables associated with perceived risk of EVD. Our study showed that community level social mobilization and community engagement were an effective strategy in the special context.

Hydrologic Response and Watershed Sensitivity to Climate Warming in California's Sierra Nevada

PubMed Central

Null, Sarah E.; Viers, Joshua H.; Mount, Jeffrey F.

2010-01-01

This study focuses on the differential hydrologic response of individual watersheds to climate warming within the Sierra Nevada mountain region of California. We describe climate warming models for 15 west-slope Sierra Nevada watersheds in California under unimpaired conditions using WEAP21, a weekly one-dimensional rainfall-runoff model. Incremental climate warming alternatives increase air temperature uniformly by 2°, 4°, and 6°C, but leave other climatic variables unchanged from observed values. Results are analyzed for changes in mean annual flow, peak runoff timing, and duration of low flow conditions to highlight which watersheds are most resilient to climate warming within a region, and how individual watersheds may be affected by changes to runoff quantity and timing. Results are compared with current water resources development and ecosystem services in each watershed to gain insight into how regional climate warming may affect water supply, hydropower generation, and montane ecosystems. Overall, watersheds in the northern Sierra Nevada are most vulnerable to decreased mean annual flow, southern-central watersheds are most susceptible to runoff timing changes, and the central portion of the range is most affected by longer periods with low flow conditions. Modeling results suggest the American and Mokelumne Rivers are most vulnerable to all three metrics, and the Kern River is the most resilient, in part from the high elevations of the watershed. Our research seeks to bridge information gaps between climate change modeling and regional management planning, helping to incorporate climate change into the development of regional adaptation strategies for Sierra Nevada watersheds. PMID:20368984

GPS Imaging of vertical land motion in California and Nevada: Implications for Sierra Nevada uplift

PubMed Central

Blewitt, Geoffrey; Kreemer, Corné

2016-01-01

Abstract We introduce Global Positioning System (GPS) Imaging, a new technique for robust estimation of the vertical velocity field of the Earth's surface, and apply it to the Sierra Nevada Mountain range in the western United States. Starting with vertical position time series from Global Positioning System (GPS) stations, we first estimate vertical velocities using the MIDAS robust trend estimator, which is insensitive to undocumented steps, outliers, seasonality, and heteroscedasticity. Using the Delaunay triangulation of station locations, we then apply a weighted median spatial filter to remove velocity outliers and enhance signals common to multiple stations. Finally, we interpolate the data using weighted median estimation on a grid. The resulting velocity field is temporally and spatially robust and edges in the field remain sharp. Results from data spanning 5–20 years show that the Sierra Nevada is the most rapid and extensive uplift feature in the western United States, rising up to 2 mm/yr along most of the range. The uplift is juxtaposed against domains of subsidence attributable to groundwater withdrawal in California's Central Valley. The uplift boundary is consistently stationary, although uplift is faster over the 2011–2016 period of drought. Uplift patterns are consistent with groundwater extraction and concomitant elastic bedrock uplift, plus slower background tectonic uplift. A discontinuity in the velocity field across the southeastern edge of the Sierra Nevada reveals a contrast in lithospheric strength, suggesting a relationship between late Cenozoic uplift of the southern Sierra Nevada and evolution of the southern Walker Lane. PMID:27917328

GPS Imaging of vertical land motion in California and Nevada: Implications for Sierra Nevada uplift.

PubMed

Hammond, William C; Blewitt, Geoffrey; Kreemer, Corné

2016-10-01

We introduce Global Positioning System (GPS) Imaging, a new technique for robust estimation of the vertical velocity field of the Earth's surface, and apply it to the Sierra Nevada Mountain range in the western United States. Starting with vertical position time series from Global Positioning System (GPS) stations, we first estimate vertical velocities using the MIDAS robust trend estimator, which is insensitive to undocumented steps, outliers, seasonality, and heteroscedasticity. Using the Delaunay triangulation of station locations, we then apply a weighted median spatial filter to remove velocity outliers and enhance signals common to multiple stations. Finally, we interpolate the data using weighted median estimation on a grid. The resulting velocity field is temporally and spatially robust and edges in the field remain sharp. Results from data spanning 5-20 years show that the Sierra Nevada is the most rapid and extensive uplift feature in the western United States, rising up to 2 mm/yr along most of the range. The uplift is juxtaposed against domains of subsidence attributable to groundwater withdrawal in California's Central Valley. The uplift boundary is consistently stationary, although uplift is faster over the 2011-2016 period of drought. Uplift patterns are consistent with groundwater extraction and concomitant elastic bedrock uplift, plus slower background tectonic uplift. A discontinuity in the velocity field across the southeastern edge of the Sierra Nevada reveals a contrast in lithospheric strength, suggesting a relationship between late Cenozoic uplift of the southern Sierra Nevada and evolution of the southern Walker Lane.

Crumble analysis of the historic sympatric distribution between Dendrortyx macroura and D. barbatus (Aves: Galliformes)

PubMed Central

2017-01-01

In Mexico, the Long-tailed Wood-Partridge (Dendrortyx macroura) is distributed in the mountains of the Trans-Mexican Volcanic Belt, Sierra Madre del Sur and Sierra Norte de Oaxaca; while the Bearded Wood-Partridge (D. barbatus) is distributed in the Sierra Madre Oriental (SMO). There is a controversial overlap in distribution (sympatry) between these two species (on the Cofre de Perote and Pico de Orizaba volcanoes, SMO and Sierra Norte de Oaxaca), based on the ambiguity and current lack of information regarding the distribution of these two species. In order to disentangle the possible presence of both species in the area of sympatry, we conducted a crumble analysis of the historic knowledge regarding the geographic distribution of both species, based on a review of scientific literature, database records, the specimen examination (in ornithological collections), field work and a reconstruction of the distribution range based on Ecological Niche Modeling. Our results support the presence of only one of these two species in the overlapping area, rejecting the existence of such an area of sympatry between the two species. We discuss alternative hypotheses that could explain the historically reported distribution pattern: 1) an error in the single existing historical record; 2) a possible local extinction of the species and 3) the past existence of interspecific competition that has since been resolved under the principle of competitive exclusion. We propose that the Santo Domingo River in northern Oaxaca and western slope of the Sierra Madre Oriental, mark the distribution limits between these species. PMID:28863140

Petrography of the Paleogene Volcanic Rocks of the Sierra Maestra, Southeastern Cuba

NASA Astrophysics Data System (ADS)

Bemis, V. L.

2006-12-01

This study is a petrographic analysis of over 200 specimens of the Paleogene volcanic rocks of the Sierra Maestra (Southerneastern Cuba), a key structure in the framework of the northern Caribbean plate boundary evolution. The purpose of this study is to understand the eruptive processes and the depositional environments. The volcanic sequence in the lower part of the Sierra Maestra begins with highly porphyritic pillow lavas, topped by massive tuffs and autoclastic flows. The presence of broken phenocrystals, palagonitic glass and hyaloclastites in this section of the sequence suggests that the prevalent mode of eruption was explosive. The absence of welding in the tuffs suggests that the rocks were emplaced in a deep submarine environment. Coherent flows, much less common than the massive tuffs, show evidence of autoclastic fracturing, also indicating low temperature-submarine environments. These observations support the hypothesis that the Sierra Maestra sequence may be neither part of the Great Antilles Arc of the Mesozoic nor any other fully developed volcanic arc, rather a 250 km long, submarine eruptive system of dikes, flows and sills, most likely a back-arc structure. The volcanic rocks of the upper sequence are all very fine grained, reworked volcaniclastic materials, often with the structures of distal turbidities, in mode and texture similar to those drilled on the Cayman Rise. This study suggests that the Sierra Maestra most likely records volcanism of diverse sources: a local older submarine source, and one or more distal younger sources, identifiable with the pan-Caribbean volcanic events of the Tertiary.

Conifer seedling survival under closed-canopy and manzanita patches in the Sierra Nevada

Treesearch

A. Plamboeck; M. North; T. Dawson

2008-01-01

After a century of fire suppression, prescribed fire and mechanical thinning are widely used to restore mixed-conifer forests in California’s Sierra Nevada, yet after these treatments, trees sometimes fail to regenerate on many sites, for several possible reasons. Notably, competition between shrubs and tree seedlings for scarce water during prolonged summer dry...

Thermal and hydrologic attributes of rock glaciers and periglacial talus landforms: Sierra Nevada, California, USA

Treesearch

Constance I. Millar; Robert D. Westfall; Diane L. Delany

2013-01-01

To explore thermal regimes and hydrologic capacity of rock glaciers and related periglacial talus landforms, mini-thermochrons were deployed in and around potentially ice-embedded features of the Sierra Nevada. Results from pilot studies at 13 rock glaciers and 7 taluses indicate that outlet springs from these landforms generally do not desiccate but persist year...

Species Composition and Habitat Associations of Benthic Algal Assemblages in Headwater Streams of the Sierra Nevada, California

Treesearch

Larry R. Brown; Jason T. May; Carolyn T. Hunsaker

2008-01-01

Despite their trophic importance and potential importance as bioindicators of stream condition, benthic algae have not been well studied in California. In particular there are few studies from small streams in the Sierra Nevada. The objective of this study was to determine the standing crop of chlorophyll-a and benthic algal species assemblages...

Riparian and upland vegetation on the Kings River Experimental Watershed, Sierra Nevada, California

Treesearch

Christopher R. Dolanc; Carolyn T. Hunsaker

2007-01-01

The Kings River Experimental Watershed (KREW) is a watershed-level study on headwater streams in the Sierra Nevada, California. Eight perennial streams, from 1500 m (4920 ft) to 2490 m (8170 ft) elevation, have been instrumented and collecting data since 2002. Component research areas of the study include stream flow, water chemistry, sediment, soil chemistry, stream...

A Statistically Based Training Diagnostic Tool for Marine Aviation

DTIC Science & Technology

2014-06-01

mission essential task list MDG maneuver description guide MOS military occupational specialty MSHARP Marine Sierra Hotel Aviation Reporting Program...include the Defense Readiness Reporting System (DRRS) Marine Corps, the Current Readiness Program (CRP), and the Marine Sierra Hotel Aviation...Beuschel, 2008). Many of these systems focus on business decisions regarding how companies can increase their bottom line, by appealing to customers more

Influence of anuran prey on the condition and distribution of Rana muscosa in the Sierra Nevada

Treesearch

K.L. Pope; K.R. Matthews

2002-01-01

Mountain yellow-legged frogs (Rana muscosa) at high elevations of the Sierra Nevada must obtain enough food during summer to survive 7–9 winter months when their aquatic habitats are frozen and food is presumably unavailable. Adults of R. muscosa prey on a variety of organisms, including aquatic and terrestrial invertebrates and...

Modeling the influence of precipitation and nitrogen deposition on forest understory fuel connectivity in Sierra Nevada mixed-conifer forest

Treesearch

M. Hurteau; M. North; T. Foines

2009-01-01

Climate change models for California’s Sierra Nevada predict greater inter-annual variability in precipitation over the next 50 years. These increases in precipitation variability coupled with increases in nitrogen deposition fromfossil fuel consumption are likely to result in increased productivity levels and significant increases in...

Transportation Observations, Considerations, and Recommendations relative to the Eastern Sierra Expanded Transit System and the Reds Meadow Shuttle Provided by the Interagency Transportation Assistance Group (TAG) / Alternative Transportation in Parks and

DOT National Transportation Integrated Search

2007-08-21

A field investigation of the current transportation issues and opportunities relative to the Eastern Sierra Expanded Transit System and the Reds Meadow Shuttle by the inter-agency Transportation Assistance Group (TAG) was conducted August 21-23, 2007...

Fisher research and the Kings River Sustainable Forest Ecosystem Project: current results and future efforts

Treesearch

Brian B. Boroski; Richard T. Golightly; Amie K. Mazzoni; Kimberly A. Sager

2002-01-01

The Kings River Sustainable Forest Ecosystems Project was initiated on the Kings River Ranger District of the Sierra National Forest, California, in 1993, with fieldwork beginning in 1994. Knowledge of the ecology of the fisher (Martes pennanti) in the Project area, and in the Sierra Nevada of California in general, is insufficient to develop...

77 FR 40171 - Endangered and Threatened Wildlife and Plants; Two Foreign Macaw Species

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-06

... the Madre de Dios department in the southeastern Peruvian Amazon (Lee 2010, p. 14). Flocks of 40 to 50 individuals have been observed in Atalya at Madre de Dios (Snyder et al. 2000, p. 125). The species has been... eastern slope of the Sierra Madre Oriental mountain range, known locally as the ``Sierra de Guatemala...

Estimating past diameters of mixed conifer species in the central Sierra Nevada

Treesearch

K. Leroy Dolph

1981-01-01

Tree diameter outside bark at an earlier period of growth can be estimated from the linear relationship of present inside bark and outside bark diameters at breast height. This note presents equations for estimating inside bark diameters, outside bark diameters, and past outside bark diameters for each of the mixed-conifer species in the central Sierra Nevada.

A density management diagram for even-aged Sierra Nevada mixed-conifer stands

Treesearch

James N. Long; John D. Shaw

2012-01-01

We have developed a density management diagram (DMD) for even-aged mixed-conifer stands in the Sierra Nevada Mountains using forest inventory and analysis (FIA) data. Analysis plots were drawn from FIA plots in California, southern Oregon, and western Nevada which included those conifer species associated with the mixed-conifer forest type. A total of 204 plots met the...

Role of oaks in fisher habitat quality in the Sierra Nevada mountains at multiple spatial scales

Treesearch

Craig M. Thompson; Kathryn Purcell; Rebecca Green; Richard. Sweitzer

2015-01-01

Fishers (Pekania pennanti) occur in ponderosa pine, mixed conifer, and mixed hardwood conifer habitats in the southern Sierra Nevada at elevations from approximately 1400 to 2300 m. They are a candidate species for listing under both the Federal and California Endangered Species Acts. Since 2007, the U.S. Department of Agriculture, Forest Service (...

Plant diversity and invasives in blue oak savannas of the southern Sierra Nevada

Treesearch

Jon E. Keeley

2002-01-01

Blue oak savannas were found to be substantially more diverse at all scales from localized point diversity to the community scale, than higher elevation shrubland and coniferous forests in the southern Sierra Nevada. Also, alien plants were more diverse and represented a substantial fraction of the understory flora in these blue oak savannas, comprising three-fourths...

Examining Internet Usage Demographic Differences and the Relationship between Internet Usage and Business Outcomes in Sierra Leone

ERIC Educational Resources Information Center

Kamara, Mohamed K.

2013-01-01

This study utilized the unified theory of acceptance and use of technology (UTAUT) to determine Internet users' perceptions and behavioral intentions to accept Wi-Fi technology deployment in Sierra Leone. The study sought to investigate (a) the Internet usage rates before and after Wi-Fi adaption in Freetown; (b) differences in Internet usage…

Developing and managing sustainable forest ecosystems for spotted owls in the Sierra Nevada

Treesearch

J. Verner; K.S. McKelvey

1994-01-01

Studies of the California spotted owl have revealed significant selection for habitats with large, old trees; relatively high basal areas of snags; and relatively high biomass in large, downed logs. Based on planning documents for national forests in the Sierra Nevada, we projected declining amounts of older-forest attributes. Region 5 has adopted measures to retain...

Understanding Sierra Leonean and Liberian Teachers' Views on Discussing Past Wars in Their Classrooms

ERIC Educational Resources Information Center

Shepler, Susan; Williams, James H.

2017-01-01

Various curricular and textbook initiatives exist to aid in the national processes of coming to terms with past violence, often serving the political goals of the victors, sometimes supported by international transitional justice institutions. Sierra Leone and Liberia each experienced a devastating civil war during the 1990s and into the 2000s,…

Landscape-level strategies for forest fuel management.

Treesearch

C. Phillip Weatherspoon; Carl N. Skinner

1996-01-01

As a result largely of human activities during the past 150 years, fires in Sierra Nevada forests occur less frequently and cover much less area than they did historically but are much more likely to be large and severe when they do occur. High-severity wildfires are considered by many to be the greatest single threat to the integrity and sustainability of Sierra...

78 FR 72926 - Bald and Golden Eagles; Migratory Birds; Phase I Development of the Chokecherry-Sierra Madre Wind...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-04

... which this notice primarily pertains, would consist of approximately 500 wind turbines, a haul road, a... development for CCSM Phase II, which will consist of about 500 additional wind turbines (roughly 1500 MW), at...-FXMB12310600000] Bald and Golden Eagles; Migratory Birds; Phase I Development of the Chokecherry-Sierra Madre Wind...

Winter sowings produce 1-0 sugar pine planting stock in the Sierra Nevada

Treesearch

James L. Jenkinson; Arthur H. McCain

1993-01-01

Seed source and sowing date effects on first-year seedling growth and Fusarium root and collar rot of sugar pine were analyzed in two consecutive nursery tests at the Pacific Southwest Research Station's Institute of Forest Genetics, near Placerville in the western Sierra Nevada. The experimental design in both tests consisted of four replications of a randomized...

Diversity of small mammals in the Sierra Nevada: Filtering by natural selection or by anthropogenic activities?

Treesearch

Douglas A. Kelt; Rahel Sollmann; Angela M. White; Susan L. Roberts; Dirk H. Van Vuren

2016-01-01

Both historical and contemporary factors may influence the structure and composition of biotas. Small mammal faunas in the Sierra Nevada of California, United States, are strongly dominated by generalist species; however, whereas 1 recent study argues that this is a product of recent anthropogenic influences, another provides a deeper evolutionary explanation based on...

Growth of White fir after Douglas-fir tussock moth outbreaks: long-term records in the Sierra Nevada.

Treesearch

Boyd E. Wickman

1986-01-01

Radial growth of white fir trees, Abies concolor (Gord. and Glend.) Lindl. ex Hildebr., defoliated almost 30 years ago by Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough), in the central Sierra Nevada was compared with 22 years of growth prior to the outbreak. There was little difference in growth between the two...

Empowering Women through Education: Evidence from Sierra Leone. NBER Working Paper No. 18016

ERIC Educational Resources Information Center

Mocan, Naci H.; Cannonier, Colin

2012-01-01

We use data from Sierra Leone where a substantial education program provided increased access to education for primary-school age children but did not benefit children who were older. We exploit the variation in access to the program generated by date of birth and the variation in resources between various districts of the country. We find that…

Fire weather and large fire potential in the northern Sierra Nevada

Treesearch

Brandon M. Collins

2014-01-01

Fuels, weather, and topography all contribute to observed fire behavior. Of these, weather is not only the most dynamic factor, it is the most likely to be directly influenced by climate change. In this study 40 years of daily fire weather observations from five weather stations across the northern Sierra Nevada were analyzed to investigate potential changes or trends...

Canopy arthropod responses to thinning and burning treatments in old-growth mixed-conifer forest in the Sierra Nevada, California

Treesearch

Thomas Rambo; Timothy Schowalter; Malcolm North

2014-01-01

We compared canopy arthropod responses to common fuels reduction treatments at Teakettle Experimental Forest in the south-central Sierra Nevada of California. We sampled arthropod communities among four dominant overstory conifer species and three dominant understory angiosperm species before and after overstory or understory thinning or no thinning treatments followed...

Rural-Urban Migration in Sierra Leone: Determinants and Policy Implications. African Rural Economy Paper No. 13.

ERIC Educational Resources Information Center

Byerlee, Derek; And Others

Study objectives were to: increase the understanding of rural to urban migration processes in Africa and Sierra Leone; develop and test a theoretical schema and survey methodology for migration research; and evaluate the effects of policy on migration. The migration survey was conducted in rural areas, urban areas, and again in the rural areas…

77 FR 53214 - Announcement of Funding Awards; Service Coordinators in Multifamily Housing Program, Fiscal Year...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-31

...,104 Center, Inc. Center. AZ Casa Sierra Vista, Casa Sierra Vista.... 600-A E 25th St...... Yuma 30 190........... 246 176,271 Senior Citizens Avenue. Housing, LTD. NM New Mexico-American La Resolana 1025 Chelwood... Corporation. OH CRS, Ltd (Stern Hendy Clifton Place........ 900 Rue De La Paix... Cincinnati 183 375,387...

77 FR 51894 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-28

... RWY 20, Orig-A Baton Rouge, LA, Baton Rouge Metropolitan, Ryan Field, ILS OR LOC RWY 22R, Amdt 11 Baton Rouge, LA, Baton Rouge Metropolitan, Ryan Field, RNAV (GPS) RWY 4L, Amdt 2 Baton Rouge, LA, Baton... Fort Huachuca/Sierra Vista, AZ, Sierra Vista Muni/Libby AAF, RADAR 1, Amdt 5, CANCELLED [FR Doc. 2012...

Canopy microclimate response to pattern and density of thinning in a Sierra Nevada forest

Treesearch

T. Rambo; M. North

2009-01-01

Restoring Sierra Nevada mixed-conifer forests after a century of fire suppression has become an important management priority as fuel reduction thinning has been mandated by the Healthy Forests Restoration Act. However, in mechanically thinned stands there is little information on the effects of different patterns and densities of live-tree retention on forest canopy...

The importance of federal grazing allotments to central Sierran oak woodland permittees: a first approximation

Treesearch

Adriana Sulak; Lynn Huntsinger

2002-01-01

The interlinkage of privately owned foothill oak woodlands and federal grazing permits in the central Sierra Nevada is examined. Knowledge of the viability of the range livestock industry is important to large-scale conservation of hardwood rangelands in the Sierran foothills. Because ranches in the Sierra often use USDA Forest Service grazing allotments, efforts at...

Response of Brown Creepers to elevation and forest edges in the southern Sierra Nevada, California

Treesearch

Kathryn Purcell; Craig Thompson; Douglas Drynan

2012-01-01

We studied the responses of the Brown Creeper (Certhia americana) to forest edges in the southern Sierra Nevada, California. We censused birds and monitored nests in four forest types over an elevational gradient. We identified habitat patches homogeneous in terms of forest type, seral stage, and canopy cover and rated edges between adjoining...

Resting structures and resting habitat of fishers in the southern Sierra Nevada, California

Treesearch

Kathryn L. Purcell; Amie K. Mazzoni; Sylvia R. Mori; Brian B. Boroski

2009-01-01

The fisher (Martes pennanti) is a forest mustelid endemic to North America that has experienced range reductions in Pacific states that have led to their listing under the Endangered Species Act as warranted but precluded by higher priorities. The viability of the southern Sierra Nevada fisher population is of particular concern due to its reduced...

Prescribed burning in the Kings River Ecosystem Project Area: lessons learned

Treesearch

David S. McCandliss

2002-01-01

The prescribed fire program on the Sierra National Forest is in its infancy. Prescription burning was initiated in 1994 in two 32,000-acre watersheds in the Kings River District of the Sierra National Forest. Primary objectives are to return fire to a more historical role in forest ecosystems and to provide opportunities for scientists from the Pacific Southwest...

Snowmelt runoff and water yield along elevation and temperature gradients in California's southern Sierra Nevada

Treesearch

Carolyn T. Hunsaker; Thomas W. Whitaker; Roger C. Bales

2012-01-01

Differences in hydrologic response across the rain-snow transition in the southern Sierra Nevada were studied in eight headwater catchments – the Kings River Experimental Watersheds – using continuous precipitation, snowpack, and streamflow measurements. The annual runoff ratio (discharge divided by precipitation) increased about 0.1 per 300 m of mean catchment...

Historical effects of logging on forests of the Cascade and Sierra Nevada ranges of California

Treesearch

William F. Laudenslayer; Herman H. Darr

1990-01-01

Ponderosa pine, Jeffrey pine, mixed conifer, and white fir forests of the Cascade and Sierra Nevada Ranges of California have been important resources and were extensively altered by timber harvest between 1850 and 1950. Many historical logging operations were small in size and of short duration. Other operations encompassed thousands of acres and existed for...

Engaging Youth in Community Change: Outcomes and Lessons Learned from Sierra Health Foundation's REACH Youth Program. Final Evaluation Report

ERIC Educational Resources Information Center

Campbell, David; Erbstein, Nancy; Fabionar, James; Wilcox, Whitney; Carrasco, Lisceth Cruz

2010-01-01

From 2006 to 2010, Sierra Health Foundation's REACH program committed $8 million to support the healthy development of youth in the Greater Sacramento, California, region. As a centerpiece of the larger grantmaking strategy, seven grantees in the region were selected to create community coalitions that involved both youth and adults in their…

Forested Communities of the Upper Montane in the Central and Southern Sierra Nevada

Treesearch

Donald A. Potter

1998-01-01

Upper montane forests in the central and southern Sierra Nevada of California were classified into 26 plant associations by using information collected from 0.1-acre circular plots. Within this region, the forested environment including the physiographic setting, geology, soils, and vegetation is described in detail. A simulation model is presented for this portion of...

Photo series for quantifying natural forest residues: southern Cascades, northern Sierra Nevada

Treesearch

Kenneth S. Blonski; John L. Schramel

1981-01-01

A total of 56 photographs shows different levels of natural fuel loadings for selected size classes in seven forest types of the southern Cascade and northern Sierra-Nevada ranges. Data provided with each photo include size, weight, volumes, residue depths, and percent of ground coverage. Stand information includes sizes, weights, and volumes of the trees sampled for...

Establishing reference conditions for streams and measuring ecological responses to management actions using aquatic invertebrate biological assessments

Treesearch

David Herbst

2004-01-01

The Sierra Nevada Ecosystem Project provided the first comprehensive status report on the condition and history of natural resources of this mountain region (Centers for Water and Wildland Resources 1996). The report concluded that aquatic habitats were the most altered and impaired ecosystems, after exposure of Sierra watersheds to 150 years of landscape changes...

Let's Begin Again: Sierra On-Line and the Origins of the Graphical Adventure Game

ERIC Educational Resources Information Center

Nooney, Laine

2017-01-01

The author retells the origin story of Sierra On-Line and its historic first product, the graphical adventure game "Mystery House." She reviews the academic and journalistic writing that placed the story almost exclusively inside a narrative about early computer games, treating it as a saga of the competition between the graphic…

KSC-2012-1013

NASA Image and Video Library

2010-09-21

POWAY, Calif. – During NASA's Commercial Crew Development Round 1 CCDev1 activities, the rocket motor under development by Sierra Nevada Corp. for its Dream Chaser spacecraft successfully fires at the company's rocket test facility located near San Diego. NASA team members reviewed the motor's system and then watched it fire three times in one day, including one firing under vacuum ignition conditions. The tests, which simulated a complete nominal mission profile, demonstrated the multiple restart capability of Sierra Nevada's hybrid rocket. Two of the company's designed and developed hybrid rocket motors will be used as the main propulsion system on the Dream Chaser after launching aboard an Atlas V rocket. Dream Chaser is one of five systems NASA invested in during CCDev1 in order to aid in the innovation and development of American-led commercial capabilities for crew transportation and rescue services to and from the International Space Station and other low Earth orbit destinations. In 2011, NASA's Commercial Crew Program CCP entered into another funded Space Act Agreement with Sierra Nevada for the second round of commercial crew development CCDev2) so the company could further develop its Dream Chaser spacecraft for NASA transportation services. For information about CCP, visit www.nasa.gov/commercialcrew. Photo credit: Sierra Nevada Corp.

KSC-2011-5119

NASA Image and Video Library

2011-07-07

CAPE CANAVERAL, Fla. -- Kennedy Space Center Director Bob Cabana, left, Mark Sirangelo, head of Sierra Nevada Space Systems (SNSS) of Sparks, Nev., and NASA Administrator Charlie Bolden pose for a photo after signing a Space Act Agreement that will offer the company technical capabilities from Kennedy's uniquely skilled work force. Kennedy will help Sierra Nevada with the ground operations support of its lifting body reusable spacecraft called "Dream Chaser," which resembles a smaller version of the space shuttle orbiter. The spacecraft would carry as many as seven astronauts to the space station. Through the new agreement, Kennedy's work force will use its experience of processing the shuttle fleet for 30 years to help Sierra Nevada define and execute Dream Chaser's launch preparations and post-landing activities. In 2010 and 2011, Sierra Nevada was awarded grants as part of the initiative to stimulate the private sector in developing and demonstrating human spaceflight capabilities for NASA's Commercial Crew Program. The goal of the program, which is based in Florida at Kennedy, is to facilitate the development of a U.S. commercial crew space transportation capability by achieving safe, reliable and cost-effective access to and from the space station and future low Earth orbit destinations. Photo credit: NASA/Jim Grossmann

Summary of the geology of the northern part of the Sierra Cuchillo, Socorroand Sierra Counties, southwestern New Mexico

USGS Publications Warehouse

Maldonado, Florian; Edited by Lucas, Spencer G.; McLemore, Virginia T.; Lueth, Virgil W.; Spielmann, Justin A.; Krainer, Karl

2012-01-01

The northern part of the Sierra Cuchillo is located within the northeastern part of the Mogollon-Datil volcanic field west of the Rio Grande rift in the Basin and Range Province, approximately 50 km northwest of Truth or Consequences in south-central New Mexico. The Sierra Cuchillo is a north-south, elongated horst block composed of Tertiary volcanic and intrusive rocks, sparse outcrops of Lower Permian and Upper Cretaceous rocks, and sediments of the Tertiary-Quaternary Santa Fe Group. The horst is composed mainly of a basal volcanic rock sequence of andesite-latite lava flows and mud-flow breccias with a 40Ar/39Ar isotopic age of about 38 Ma. The sequence is locally intruded by numerous dikes and plugs that range in composition from basaltic andesite through rhyolite and granite. The andesite-latite sequence is overlain by ash-flow tuffs and a complex of rhyolitic lava flows and domes. Some of these units are locally derived and some are outflow sheets derived from calderas in the San Mateo Mountains, northeast of the study area. These locally derived units and outflow sheets range in age from 28 to 24 Ma.

Occurrence and transport of total mercury and methyl mercury in the Sacramento River Basin, California

USGS Publications Warehouse

Domagalski, Joseph L.

1999-01-01

Mercury poses a water-quality problem for California's Sacramento River, a large river with a mean annual discharge of over 650 m3/s. This river discharges into the San Francisco Bay, and numerous fish species of the bay and river contain mercury levels high enough to affect human health if consumed. Two possible sources of mercury are the mercury mines in the Coast Ranges and the gold mines in the Sierra Nevada. Mercury was once mined in the Coast Ranges, west of the Sacramento River, and used to process gold in the Sierra Nevada, east of the river. The mineralogy of the Coast Ranges mercury deposits is mainly cinnabar (HgS), but elemental mercury was used to process gold in the Sierra Nevada. Residual mercury from mineral processing in the Sierra Nevada is mainly in elemental form or in association with oxide particles or organic matter and is biologically available. Recent bed-sediment sampling, at sites below large reservoirs, showed elevated levels of total mercury (median concentration 0.28 ??g/g) in every large river (the Feather, Yuba, Bear, and American rivers) draining the Sierra Nevada gold region. Monthly sampling for mercury in unfiltered water shows relatively low concentrations during the nonrainy season in samples collected throughout the Sacramento River Basin, but significantly higher concentrations following storm-water runoff. Measured concentrations, following storm-water runoff, frequently exceeded the state of California standards for the protection of aquatic life. Results from the first year of a 2-year program of sampling for methyl mercury in unfiltered water showed similar median concentrations (0.1 ng/l) at all sampling locations, but with apparent high seasonal concentrations measured during autumn and winter. Methyl mercury concentrations were not significantly higher in rice field runoff water, even though rice production involves the creation of seasonal wetlands: higher rates of methylation are known to occur in stagnant wetland environments that have high dissolved carbon.Mercury poses a water-quality problem for California's Sacramento River, a large river with a mean annual discharge of over 650 m3/s. This river discharges into the San Francisco Bay, and numerous fish species of the bay and river contain mercury levels high enough to affect human health if consumed. Two possible sources of mercury are the mercury mines in the Coast Ranges and the gold mines in the Sierra Nevada. Mercury was once mined in the Coast Ranges, west of the Sacramento River, and used to process gold in the Sierra Nevada east of the river. The mineralogy of the Coast Ranges mercury deposits is mainly cinnabar (HgS), but elemental mercury was used to process gold in the Sierra Nevada. Residual mercury from mineral processing in the Sierra Nevada is mainly in elemental form or in association with oxide particles or organic matter and is biologically available. Recent bed-sediment sampling, at sites below large reservoirs, showed elevated levels of total mercury (median concentration 0.28 ??g/g) in every large river (the Feather, Yuba, Bear, and American rivers) draining the Sierra Nevada gold region. Monthly sampling for mercury in unfiltered water shows relatively low concentrations during the nonrainy season in samples collected throughout the Sacramento River Basin, but significantly higher concentrations following storm-water runoff. Measured concentrations, following storm-water runoff, frequently exceeded the state of California standards for the protection of aquatic life. Results from the first year of a 2-year program of sampling for methyl mercury in unfiltered water showed similar median concentrations (0.1 ng/l) at all sampling locations, but with apparent high seasonal concentrations measured during autumn and winter. Methyl mercury concentrations were not significantly higher in rice field runoff water, even though rice production involves the creation of seasonal wetlands: higher rates of methylation a

Crustal extension and magmatism during the mid-Cenozoic ignimbrite flare-up in the Guazapares Mining District and Cerocahui basin regions, northern Sierra Madre Occidental, western Chihuahua, Mexico

NASA Astrophysics Data System (ADS)

Murray, Bryan Patrick

Silicic large igneous provinces are significant in the geologic record, due to their unusually extensive areal coverage (>100,000 km2) and large volumes (>250,000 km3), and may be characteristic of continental regions undergoing broad lithospheric extension. The Sierra Madre Occidental of northwestern Mexico is the biggest and best-preserved silicic large igneous province of the Cenozoic and is considered part of the extensive mid-Cenozoic ignimbrite flare-up that affected much of the southwestern North American Cordillera. Despite its size and preservation, very little is known about the geology of the Sierra Madre Occidental, and the timing and spatial extent of ignimbrite flare-up volcanism in relation to crustal extension is relatively unknown. This study presents new geologic mapping, stratigraphy, zircon U-Pb laser ablation ICP-MS dating, modal analysis, and geochemical data from the Guazapares Mining District and Cerocahui basin regions, two adjacent areas of the northern Sierra Madre Occidental in western Chihuahua. The rock exposure and topographic relief in this previously unmapped ~450 km2 area make it ideal for studying the relationships between silicic large igneous province volcanism and crustal extension. Three informal formations are identified in the study area: (1) the ca. 27.5 Ma Parajes formation, a ~1-km-thick succession of primarily welded silicic outflow ignimbrite sheets erupted from sources within ~50--100 km of the study area that were active during the Early Oligocene pulse of the mid-Cenozoic ignimbrite flare-up; (2) the ca. 27--24.5 Ma Temoris formation, composed primarily of locally erupted mafic-intermediate lavas and associated intrusions with interbedded alluvial deposits, likely related to rocks of the Southern Cordillera basaltic andesite province that were intermittently erupted across all of the northern Sierra Madre Occidental following the Early Oligocene ignimbrite pulse; and (3) the ca. 24.5--23 Ma Sierra Guazapares formation, composed of silicic vent to proximal facies ignimbrites, lavas, plugs, and reworked equivalents that record the initiation of explosive and effusive silicic fissure magmatism in the study area during the Early Miocene pulse of the mid-Cenozoic ignimbrite flare-up. The Guazapares Mining District and Cerocahui basin regions share this stratigraphy, but the rocks in the Cerocahui basin consist of a much higher proportion of alluvial deposits. The main geologic structures in the Guazapares Mining District and Cerocahui basin regions are NNW-trending normal faults, with an estimated minimum of 20% total horizontal extension. Many normal faults bound half-graben basins that show evidence of syndepositional extension. Normal faulting began by ca. 27.5 Ma during deposition of the youngest ignimbrites of the Parajes formation, concurrent with the end of the Early Oligocene silicic ignimbrite pulse of the ignimbrite flare-up to the east and before magmatism began in the study area. Preexisting normal faults localized mafic-intermediate volcanic vents of the Temoris formation and silicic vents of the Sierra Guazapares formation, and were active during deposition of these formations. In addition, the localization and timing of epithermal mineralization in the Guazapares Mining District appears to be favored where pre-to-synvolcanic extensional structures are in close association with Sierra Guazapares formation rhyolite plugs. The timing of extensional faulting and magmatism in the Guazapares Mining District and Cerocahui regions is consistent with regional-scale Middle Eocene to Early Miocene southwestward migration of active volcanism and extension in the northern Sierra Madre Occidental. Extension accompanied mafic-intermediate and silicic volcanism in the study area, and overlapped with the peak of mid-Cenozoic ignimbrite flare-up in the Sierra Madre Occidental; this supports the interpretation that there is likely a relationship between lithospheric extension and silicic large igneous province magmatism.

Spatiotemporal patterns of fault slip rates across the Central Sierra Nevada frontal fault zone

NASA Astrophysics Data System (ADS)

Rood, Dylan H.; Burbank, Douglas W.; Finkel, Robert C.

2011-01-01

Patterns in fault slip rates through time and space are examined across the transition from the Sierra Nevada to the Eastern California Shear Zone-Walker Lane belt. At each of four sites along the eastern Sierra Nevada frontal fault zone between 38 and 39° N latitude, geomorphic markers, such as glacial moraines and outwash terraces, are displaced by a suite of range-front normal faults. Using geomorphic mapping, surveying, and 10Be surface exposure dating, mean fault slip rates are defined, and by utilizing markers of different ages (generally, ~ 20 ka and ~ 150 ka), rates through time and interactions among multiple faults are examined over 10 4-10 5 year timescales. At each site for which data are available for the last ~ 150 ky, mean slip rates across the Sierra Nevada frontal fault zone have probably not varied by more than a factor of two over time spans equal to half of the total time interval (~ 20 ky and ~ 150 ky timescales): 0.3 ± 0.1 mm year - 1 (mode and 95% CI) at both Buckeye Creek in the Bridgeport basin and Sonora Junction; and 0.4 + 0.3/-0.1 mm year - 1 along the West Fork of the Carson River at Woodfords. Data permit rates that are relatively constant over the time scales examined. In contrast, slip rates are highly variable in space over the last ~ 20 ky. Slip rates decrease by a factor of 3-5 northward over a distance of ~ 20 km between the northern Mono Basin (1.3 + 0.6/-0.3 mm year - 1 at Lundy Canyon site) to the Bridgeport Basin (0.3 ± 0.1 mm year - 1 ). The 3-fold decrease in the slip rate on the Sierra Nevada frontal fault zone northward from Mono Basin is indicative of a change in the character of faulting north of the Mina Deflection as extension is transferred eastward onto normal faults between the Sierra Nevada and Walker Lane belt. A compilation of regional deformation rates reveals that the spatial pattern of extension rates changes along strike of the Eastern California Shear Zone-Walker Lane belt. South of the Mina Deflection, extension is accommodated within a diffuse zone of normal and oblique faults, with extension rates increasing northward on the Fish Lake Valley fault. Where faults of the Eastern California Shear Zone terminate northward into the Mina Deflection, extension rates increase northward along the Sierra Nevada frontal fault zone to ~ 0.7 mm year - 1 in northern Mono Basin. This spatial pattern suggests that extension is transferred from more easterly fault systems, e.g., Fish Lake Valley fault, and localized on the Sierra Nevada frontal fault zone as the Eastern California Shear Zone-Walker Lane belt faulting is transferred through the Mina Deflection.

High Compressive Stresses Near the Surface of the Sierra Nevada, California

NASA Astrophysics Data System (ADS)

Martel, S. J.; Logan, J. M.; Stock, G. M.

2012-12-01

Observations and stress measurements in granitic rocks of the Sierra Nevada, California reveal strong compressive stresses parallel to the surface of the range at shallow depths. New overcoring measurements show high compressive stresses at three locations along an east-west transect through Yosemite National Park. At the westernmost site (west end of Tenaya Lake), the mean compressive stress is 1.9. At the middle site (north shore of Tenaya Lake) the mean compressive stress is 6.8 MPa. At the easternmost site (south side of Lembert Dome) the mean compressive stress is 3.0 MPa. The trend of the most compressive stress at these sites is within ~30° of the strike of the local topographic surface. Previously published hydraulic fracturing measurements by others elsewhere in the Sierra Nevada indicate surface-parallel compressive stresses of several MPa within several tens of meters of the surface, with the stress magnitudes generally diminishing to the west. Both the new and the previously published compressive stress magnitudes are consistent with the presence of sheeting joints (i.e., "exfoliation joints") in the Sierra Nevada, which require lateral compressive stresses of several MPa to form. These fractures are widespread: they are distributed in granitic rocks from the north end of the range to its southern tip and across the width of the range. Uplift along the normal faults of the eastern escarpment, recently measured by others at ~1-2 mm/yr, probably contributes to these stresses substantially. Geodetic surveys reveal that normal faulting flexes a range concave upwards in response to fault slip, and this flexure is predicted by elastic dislocation models. The topographic relief of the eastern escarpment of the Sierra Nevada is 2-4 km, and since alluvial fill generally buries the bedrock east of the faults, the offset of granitic rocks is at least that much. Compressive stresses of several MPa are predicted by elastic dislocation models of the range front faults of the eastern Sierra Nevada for as little as 100m of slip. The compression is consistent with a concave up flexure of the surface of the range. Conversely, elastic models also predict that markedly lower compressive stresses or even a tension would exist on exposed bedrock on the down-dropped hanging wall east of the range front faults. To test this prediction, we measured stresses at a fourth site, in the granitic rock of the Aeolian Buttes, which is east of the range front faults. The mean compressive stress there is 0.26 MPa, more than an order of magnitude less than the average at the three Yosemite sites. The measured stress magnitudes near the topographic surface of the Sierra, the distribution of sheeting joints west of the range front faults, and elastic model predictions are broadly consistent and indicate that the high compressive stresses at the surface of the Sierra Nevada are largely associated with uplift of the range, although other contributions cannot be excluded.

Effects on nonnative fishes on wilderness lake ecosystems in the Sierra Nevada and recommendations for reducing impacts

Treesearch

R. A. Knapp; Kathleen R. Matthews

2000-01-01

Wilderness areas of the Sierra Nevada, California contain thousands of lakes and ponds, nearly all of which were historically fishless. After more than a century of fish stocking, introduced trout are now present in up to 80% of larger lakes. These nonnative fishes have had profound impacts on native fishes, amphibians, and invertebrates. Several of these native...

Response of Subalpine Conifers in the Sierra Nevada, California, U.S.A., to 20th-Century Warming and Decadal Climate Variability

Treesearch

Constance I. Millar; Robert D. Westfall; Diane L. Delany; John C. King; Lisa J. Graumlich

2004-01-01

Four independent studies of conifer growth between 1880 and 2002 in upper elevation forests of the central Sierra Nevada, California, U.S.A., showed correlated multidecadal and century-long responses associated with climate. Using tree-ring and ecological plot analysis, we studied annual branch growth of krummholz Pinus albicaulis; invasion by P....

Mastication and prescribed fire impacts on fuels in a 25-year old ponderosa pine plantation, southern Sierra Nevada

Treesearch

Alicia L. Reiner; Nicole M. Vaillant; JoAnn Fites-Kaufman; Scott N. Dailey

2009-01-01

Due to increases in tree density and hazardous fuel loading in Sierra Nevadan forests, land management is focusing on fuel reduction treatments to moderate the risk of catastrophic fires. Fuel treatments involving mechanical and prescribed fire methods can reduce surface as well as canopy fuel loads. Mastication is a mechanical method which shreds smaller trees and...

Granite Exfoliation, Cosumnes River Watershed, Somerset, California

NASA Astrophysics Data System (ADS)

Crockett, I. Q.; Neiss-Cortez, M.

2015-12-01

In the Sierra Nevada foothills of California there are many exposed granite plutons within the greater Sierra Nevada batholith. As with most exposed parts of the batholith, these granite slabs exfoliate. It is important to understand exfoliation for issues of public safety as it can cause rock slides near homes, roads, and recreation areas. Through observation, measuring, and mapping we characterize exfoliation in our Cosumnes River watershed community.

Reproduction, abundance, and population growth for a fisher (Pekania pennanti) population in the Sierra National Forest, California

Treesearch

Rick A. Sweitzer; Viorel D. Popescu; Reginald H. Barrett; Kathryn L. Purcell; Craig M. Thompson

2015-01-01

In the west coast region of the United States, fishers (Pekania pennanti) exist in 2 remnant populations—1 in northern California and 1 in the southern Sierra Nevada, California—and 3 reintroduced populations (western Washington, southern Oregon, and northeastern California). The West Coast Distinct Population Segment of fishers encompassing all of...

A dendrochronology based fire history of Jeffry pine-mixed conifer forests in the Sierra San Pedro Martir, Mexico

Treesearch

Scott L. Stephens; Carl N. Skinner; Samantha J. Gill

2003-01-01

Conifer forests in northwestern Mexico have not experienced systematic fire suppression or logging, making them unique in western North America. Fire regimes of Pinus jeffreyi Grev. & Balf. mixed conifer forests in the Sierra San Pedro Martir, Baja California, Mexico, were determined by identifying 105 fire dates from 1034 fire scars in 105 specimens. Fires were...

PAST CLIMATES, FORESTS, AND DISTURBANCES OF THE SIERRA NEVADA, CALIFORNIA: UNDERSTANDING THE PAST TO MANAGE FOR THE FUTURE

Treesearch

William F. Laudenslayer; Carl N. Skinner

1995-01-01

The forests of the Sierra Nevada have been altered for millennia by climate, natural disturbances, and more recently by the activities of humans. Management of these forests and their resources as ecosystems to meet diverse objectives, requires an understanding of the conditions under which existing forests developed and how they have changed through time. Recently...

78 FR 53477 - Notice of Relocation of the Bureau of Land Management's San Pedro Project Office in Sierra Vista, AZ

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-29

... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLAZG02000.L143000000.EQ0000.TAS:14X1109.241A] Notice of Relocation of the Bureau of Land Management's San Pedro Project Office in Sierra Vista... relocation of the Bureau of Land Management's (BLM) San Pedro Project Office (SPPO), temporary closure of the...

NASA Acting Deputy Chief Technologist Vicki Crisp Discusses Sierra Nevada Corporation's Dream Chaser with Lee Archambault

NASA Image and Video Library

2017-08-30

NASA Acting Deputy Chief Technologist Vicki Crisp discusses Sierra Nevada Corporation’s Dream Chaser captive carry flight and future tests with former Astronaut Lee "Bru" Archambault, who is now a test pilot for the American company. The Dream Chaser completed a successful captive carry flight at NASA’s Armstrong Flight Research Center at Edwards, California, on Aug. 30, 2017.

Simulating fire and forest dynamics for a coordinated landscape fuel treatment project in the Sierra Nevada

Treesearch

Brandon M. Collins; Scott L. Stephens; Gary B. Roller; John Battles

2011-01-01

We evaluate an actual landscape fuel treatment project that was designed by local U. S. Forest Service managers in the northern Sierra Nevada. We model the effects of this project at reducing landscape-level fire behavior at multiple time steps, up to nearly 30 yr beyond treatment implementation. Additionally, we modeled planned treatments under multiple diameter-...

Response of high-elevation limber pine (Pinus flexilis) to multiyear droughts and 20th-century warming, Sierra Nevada, California, USA

Treesearch

Constance I. Millar; Robert D. Westfall; Diane L. Delany

2007-01-01

Limber pine (Pinus flexilis James) stands along the eastern escarpment of the Sierra Nevada, California, experienced significant mortality from 1985 to 1995 during a period of sustained low precipitation and high temperature. The stands differ from old-growth limber pine forests in being dense, young, more even-aged, and located in warmer, drier...

Fire and fire surrogate study in the Sierra Nevada: evaluating restoration treatments at Blodgett Forest and Sequoia National Park

Treesearch

Eric E. Knapp; Scott L. Stephens; James D. McIver; Jason J. Moghaddas; Jon E. Keeley

2004-01-01

Management practices have altered both the structure and function of forests throughout the United States. Some of the most dramatic changes have resulted from fire exclusion, especially in forests that historically experienced relatively frequent, low- to moderate-intensity fire regimes. In the Sierra Nevada, fire exclusion is believed to have resulted in widespread...

Impacts of rodenticide and insecticide toxicants from marijuana cultivation on fisher survival rates in the Sierra National Forest, California.

Treesearch

Craig Thompson; Kathryn Purcell

2013-01-01

Secondary exposure of wildlife to pesticides has been well documented, yet exposure is typically associated with agricultural or wildland-urban interface areas. Wildlife in undeveloped areas is generally presumed free from risk. In 2009, a male fisher was found dead in the Sierra National Forest and subsequent necropsy revealed that the animal died of acute rodenticide...

Rock glaciers and related periglacial landforms in the Sierra Nevada, CA, USA; inventory, distribution and climatic relationships

Treesearch

Constance I. Millar; Robert D. Westfall

2008-01-01

Rock glaciers and related periglacial rock-ice features (RIFs) are abundant yet overlooked landforms in the Sierra Nevada, California, where they occur in diverse forms. We mapped 421 RIFs from field surveys, and grouped these into six classes based on morphology and location. These categories comprise a greater range of frozen-ground features than are commonly...

Black bear abundance, habitat use, and food habits in the Sierra San Luis, Sonora, Mexico

Treesearch

Rodrigo Sierra Corona; Ivan A. Sayago Vazquez; M. del Carmen Silva Hurtado; Carlos A. Lopez Gonzalez

2005-01-01

We studied black bears to determine habitat use, food habits, and abundance between April 2002 and November 2003 in the Sierra San Luis, Sonora. We utilized transects to determine spoor presence, camera traps for abundance, and scat analysis. During 2002, bears fed principally on plant material, and for 2003 on animal matter, namely livestock. Habitat use differed...

Ozone injury responses of ponderosa and Jeffrey pine in the Sierra Nevada and San Bernardino Mountains in California

Treesearch

Paul Miller; Raleigh Guthrey; Susan Schilling; John Carroll

1998-01-01

Ozone injury was monitored on foliage of ponderosa (Pinus ponderosa Dougl. ex Laws.) and Jeffrey (Pinus jeffreyi Grev. & Balf.) pines at 11 locations in the Sierra Nevada and 1 site in the San Bernardino Mountains of southern California. Ozone injury on all age cohorts of needles on about 1,600 trees was surveyed annually from...

Evaluating avian-habitat relationships models in mixed-conifer forests of the Sierra Nevada

Treesearch

Kathryn L. Purcell; Sallie J. Hejl; Terry A. Larson

1992-01-01

Using data from two studies in the southern and central Sierra Nevada, we compared the presence and abundance of bird species breeding in mixedconifer forests during 1978-79 and 1983-85 to predictions &om the California Wildlife Habitat Relationships (WHR) System. Twelve percent of the species observed in either study were not predicted by the WHR database to occur...

Meta-analysis of California Spotted Owl (Strix occidentalis occidentalis) territory occupancy in the Sierra Nevada: habitat associations and their implications for forest management

Treesearch

Douglas J. Tempel; John J. Keane; R. J. Gutierrez; Jared D. Wolfe; Gavin M. Jones; Alexander Koltunov; Carlos M. Ramirez; William J. Berigan; Claire V. Gallagher; Thomas E. Munton; Paula A. Shaklee; Sheila A. Whitmore; M. Zachariah Peery

2016-01-01

We assessed the occupancy dynamics of 275 California Spotted Owl (Strix occidentalis occidentalis) territories in 4 study areas in the Sierra Nevada, California, USA, from 1993 to 2011. We used Landsat data to develop maps of canopy cover for each study area, which we then used to quantify annual territory-specific habitat...

Controls of streamflow generation in small catchments across the snow-rain transition in the southern Sierra Nevada, California

Treesearch

Fengjing Liu; Carolyn Hunsaker; Roger C. Bales

2012-01-01

Processes controlling streamflow generation were determined using geochemical tracers for water years 2004–2007 at eight headwater catchments at the Kings River Experimental Watersheds in southern Sierra Nevada. Four catchments are snowdominated, and four receive a mix of rain and snow. Results of diagnostic tools of mixing models indicate that Ca2+...

Influence of climate and land use on historical surface fires in pine-oak forests, Sierra Madre Occidental, Mexico

Treesearch

Emily K. Heyerdahl; Ernesto Alvarado

2003-01-01

The rugged mountains of the Sierra Madre Occidental, in north-central Mexico, support a mosaic of diverse ecosystems. Of these, the high-elevation, temperate pine-oak forests are ecologically significant for their extensiveness and biodiversity. They cover nearly half the land area in the states of Durango and Chihuahua (42%), and comprise a similar percentage of the...

Climate change and fire regimes in the Sierra de Manantlan, Mexico

Treesearch

Brooke A. Cassell; Ernesto Alvarado; Emily Heyerdahl; Diego Perez-Salicrup; Enrique Jardel-Pelaez

2010-01-01

Fire has been attributed as one of the most influential factors in vegetation community and succession in the Sierra de Manantlán Biosphere Reserve in Jalisco and Colima, México. A mosaic of low, mixed and high severity fire regimes characterizes the landscape with ecosystems ranging from mesophyllous mountain forest to higher elevation pine and oak forest. Research...

Hydrogeologic influence on changes in snowmelt runoff with climate warming: Numerical experiments on a mid-elevation catchment in the Sierra Nevada, USA

Treesearch

S.M. Jepsen; T.C. Harmon; M.W. Meadows; C.T. Hunsaker

2016-01-01

The role of hydrogeology in mediating long-term changes in mountain streamflow, resulting from reduced snowfall in a potentially warmer climate, is currently not well understood. We explore this by simulating changes in stream discharge and evapotranspiration from a mid-elevation, 1-km2 catchment in the southern Sierra Nevada of California (USA)...

Confronting the implications of wicked problems: changes needed in Sierra Nevada National Forest planning and problem solving

Treesearch

Hal Salwasser

2004-01-01

Thirty years ago, the fate of migratory deer in the Sierra Nevada was thought to be the major forest wildlife issue. Ten years later, agencies were building the California Wildlife Habitat Relationships System to allow managers to integrate all terrestrial vertebrates with timber management in comprehensive National Forest planning. Another ten years after that, Tom...

Carbon and nutrient contents in soils from the Kings River Experimental Watersheds, Sierra Nevada Mountains, California

Treesearch

D.W. Johnson; C.T. Hunsaker; D.W. Glass; B.M. Rau; B.A. Roath

2011-01-01

Soil C and nutrient contents were estimated for eight watersheds in two sites (one high elevation, Bull, and one low elevation, Providence) in the Kings River Experimental Watersheds in the western Sierra Nevada Mountains of California. Eighty-seven quantitative pits were dug to measure soil bulk density and total rock content, while three replicate surface samples...

"Farming Miners" or "Mining Farmers"?: Diamond Mining and Rural Development in Post-Conflict Sierra Leone

ERIC Educational Resources Information Center

Maconachie, Roy; Binns, Tony

2007-01-01

Sierra Leone is currently emerging from a brutal civil war that lasted most of the 1990s, and now has the dubious distinction of being ranked among the world's poorest countries. As thousands of displaced people move back to their villages, a large proportion of the predominantly farm-based rural population are growing food crops for the first…

Climate change in wildland management: taking the long view

Treesearch

Scott Stine

2004-01-01

Climate constitutes one of the great determinants of all natural environments. As such, it goes a long way in accounting for the distributions of the plant and animal species that inhabit the Sierra Nevada today. Most land managers are well aware that climate has changed over geologic time—indeed, one needs to look no farther than the polished rock of high Sierra...

Survival of fishers in the southern Sierra Nevada region of California

Treesearch

Richard A. Sweitzer; Craig M. Thompson; Rebecca E. Green; Reginald H. Barrett; Kathryn L. Purcell

2015-01-01

Fishers in the western United States were recently proposed for listing under the U.S. Endangered Species Act because of concerns for loss of suitable habitat and evidence of a diversity of mortality risks that reduce survival. One of 2 remnant populations of fishers in California is in the southern Sierra Nevada region, where we studied them at 2 research sites in the...

Windthrown trees on the Kings River Ranger District, Sierra National Forest: meteorological aspects

Treesearch

Michael A. Fosberg

1986-01-01

Blowdown in shelterwood, sanitation cuts, and other partial cuts on the Kings River Ranger District, Sierra National Forest, are due to Mono winds. Both winter storm and Mono winds were considered as causes of winter blowdown. All evidence, e.g., direction of tree-fall and occurrence of high wind events, point to Mono wind events as the cause of blowdown. Only 12...

Sierra Leone's Former Child Soldiers: A Follow-Up Study of Psychosocial Adjustment and Community Reintegration

ERIC Educational Resources Information Center

Betancourt, Theresa Stichick; Borisova, Ivelina Ivanova; Williams, Timothy Philip; Brennan, Robert T.; Whitfield, Theodore H.; de la Soudiere, Marie; Williamson, John; Gilman, Stephen E.

2010-01-01

This is the first prospective study to investigate psychosocial adjustment in male and female former child soldiers (ages 10-18; n = 156, 12% female). The study began in Sierra Leone in 2002 and was designed to examine both risk and protective factors in psychosocial adjustment. Over the 2-year period of follow-up, youth who had wounded or killed…

Truffle abundance in riparian and upland mixed-conifer forest of California's southern Sierra Nevada

Treesearch

Marc D. Meyer; Malcolm P. North

2005-01-01

We compared the abundance, diversity, and composition of truffles in riparian and upland areas within a mixed-conifer forest of the Sierra Nevada of California. We sampled for truffles in a single watershed over two seasons (spring and summer) and 4 years to determine whether truffles were more abundant and diverse in riparian than upland sites in old-growth, mixed-...

Business Case Analysis: Increasing Air Force Dining Hall Use as an Alternative to Closure

DTIC Science & Technology

2011-12-01

work on 3 new food stations at the Sierra Inn, as well as a daily buffet line. They introduced a new deli, grill, and salad bar as well as a “Just4U...courses, starches, and vegetables, it is not uncommon for the Sierra Inn to offer six to eight main courses, a sandwich bar, soup and salad bar, and

Abundance and rates of brood parasitism by brown-headed cowbirds over an elevational gradient in the southern Sierra Nevada

Treesearch

Kathryn Purcell; Jared Verner

1999-01-01

We studied Brown-headed Cowbird (Molothrus ater) parasitism rates in four forest types (ponderosa pine, mixed conifer, true fir, and lodgepole pine) over an elevational gradient in the southern Sierra Nevada. Cowbirds were most abundant and parasitism rates were highest at the lowest sites. All but one of 17 parasitized nests were found in the...

Aircraft measurements of nitrogen and phosphorus in and around the Lake Tahoe Basin: implications for possible sources of atmospheric pollutants to Lake Tahoe.

PubMed

Zhang, Qi; Carroll, John J; Dixon, Alan J; Anastasio, Cort

2002-12-01

Atmospheric deposition of nitrogen (N) and phosphorus (P) into Lake Tahoe appears to have been a major factor responsible for the shifting of the lake's nutrient response from N-limited to P-limited. To characterize atmospheric N and P in and around the Lake Tahoe Basin during summer, samples were collected using an instrumented aircraft flown over three locations: the Sierra Nevada foothills east of Sacramento ("low-Sierra"), further east and higher in the Sierra ("mid-Sierra"), and in the Tahoe Basin. Measurements were also made within the smoke plume downwind of an intense forest fire just outside the Tahoe Basin. Samples were collected using a denuder-filter pack sampling system (DFP) and analyzed for gaseous and water-soluble particle components including HNO3/ NO3-, NH3 /NH4+, organic N (ON), total N, SRP (soluble reactive phosphate) and total P. The average total gaseous and particulate N concentrations (+/- 1sigma) measured over the low- and mid-Sierra were 660 (+/- 270) and 630 (+/- 350) nmol N/m3-air, respectively. Total airborne N concentrations in the Tahoe samples were one-half to one-fifth of these values. The forest fire plume had the highest concentration of atmospheric N (860 nmol N/m3-air) and a greater contribution of organic N (ON) to the total N compared to nonsmoky conditions. Airborne P was rarely observed over the low- and mid-Sierra but was present at low concentrations over Lake Tahoe, with average +/- 1sigma) concentrations of 2.3 +/- 2.9 and 2.8 +/- 0.8 nmol P/m3-air under typical clear air and slightly smoky air conditions, respectively. Phosphorus in the forestfire plume was present at concentrations approximately 10 times greater than over the Tahoe Basin. P in these samples included both fine and coarse particulate phosphate as well as unidentified, possibly organic, gaseous P species. Overall, our results suggest that out-of-basin emissions could be significant sources of nitrogen to Lake Tahoe during the summer and that forest fires could be important sources of both N and P.

Current Sierra Nevada-North America motion from very long baseline interferometry: Implications for the kinematics of the western United States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Argus, D.F.; Gordon, R.G.

1991-11-01

The authors use geodetic measurements from very long baseline interferometry to estimate the motion of the Sierra Nevadan microplate. The motion of the Sierra Nevadan microplate relative to the North American plate is described by a right-handed rotation of 0.61{degree}/m.y. about lat 32{degree}N, long 128{degree}W. This Euler pole predicts a significant counterclockwise rotation about a local vertical axis. It further predicts a velocity of the eastern edge of the Sierra Nevada relative to stable North America of 11 {plus minus}1 mm/yr toward N36{degree} {plus minus}3{degree}W, which accounts for about one-fourth of the velocity between the Pacific and North American platesmore » and is {approximately}25{degree} clockwise of many prior estimates. The velocity nearly parallels the boundary between the Sierra Nevada and the Great Basin, which implies that current motion within the Great Basin results in a rotational, noncoaxial deformation. The authors use this velocity to estimate how motion is distributed across the broad deforming zone taking up Pacific-North America plate motion. They find that the vector sum of strike slip along the San Andreas fault and motion of the Sierra Nevada relative to stable North America (taken up by deformation within the Great Basin) differs little from the Pacific-north America plate velocity. The difference can be described at 36{degree}N along the San Andreas fault by a vector of 6 mm/yr directed toward N20{degree}W. This vector resolves into components of 5 mm/yr parallel to the fault and 2 mm/yr perpendicular to the fault with 95% confidence intervals of 0 to 10 mm/yr and {minus}1 to +5 mm/yr, respectively. The authors conclude that motion previously inferred to be taken up by deformation other than strike slip along the San Andreas fault or deformation within the Great Basin is much smaller than previously thought.« less

Implementing an Ebola Vaccine Study - Sierra Leone.

PubMed

Widdowson, Marc-Alain; Schrag, Stephanie J; Carter, Rosalind J; Carr, Wendy; Legardy-Williams, Jennifer; Gibson, Laura; Lisk, Durodami R; Jalloh, Mohamed I; Bash-Taqi, Donald A; Kargbo, Samuel A Sheku; Idriss, Ayesha; Deen, Gibrilla F; Russell, James B W; McDonald, Wendi; Albert, Alison P; Basket, Michelle; Callis, Amy; Carter, Victoria M; Ogunsanya, Kelli R Clifton; Gee, Julianne; Pinner, Robert; Mahon, Barbara E; Goldstein, Susan T; Seward, Jane F; Samai, Mohamed; Schuchat, Anne

2016-07-08

In October 2014, the College of Medicine and Allied Health Sciences of the University of Sierra Leone, the Sierra Leone Ministry of Health and Sanitation, and CDC joined the global effort to accelerate assessment and availability of candidate Ebola vaccines and began planning for the Sierra Leone Trial to Introduce a Vaccine against Ebola (STRIVE). STRIVE was an individually randomized controlled phase II/III trial to evaluate efficacy, immunogenicity, and safety of the recombinant vesicular stomatitis virus Ebola vaccine (rVSV-ZEBOV). The study population was health care and frontline workers in select chiefdoms of the five most affected districts in Sierra Leone. Participants were randomized to receive a single intramuscular dose of rVSV-ZEBOV at enrollment or to receive a single intramuscular dose 18-24 weeks after enrollment. All participants were followed up monthly until 6 months after vaccination. Two substudies separately assessed detailed reactogenicity over 1 month and immunogenicity over 12 months. During the 5 months before the trial, STRIVE and partners built a research platform in Sierra Leone comprising participant follow-up sites, cold chain, reliable power supply, and vaccination clinics and hired and trained at least 350 national staff. Wide-ranging community outreach, informational sessions, and messaging were conducted before and during the trial to ensure full communication to the population of the study area regarding procedures and current knowledge about the trial vaccine. During April 9-August 15, 2015, STRIVE enrolled 8,673 participants, of whom 453 and 539 were also enrolled in the safety and immunogenicity substudies, respectively. As of April 28, 2016, no Ebola cases and no vaccine-related serious adverse events, which by regulatory definition include death, life-threatening illness, hospitalization or prolongation of hospitalization, or permanent disability, were reported in the study population. Although STRIVE will not produce an estimate of vaccine efficacy because of low case frequency as the epidemic was controlled, data on safety and immunogenicity will support decisions on licensure of rVSV-ZEBOV.The activities summarized in this report would not have been possible without collaboration with many U.S. and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html).

Interactions between cold and water limitation along a climate gradient produce sharp thresholds in ecosystem type, carbon balance, and water cycling

NASA Astrophysics Data System (ADS)

Kelly, A. E.; Goulden, M.; Fellows, A. W.

2013-12-01

California's Mediterranean climate supports a broad diversity of ecosystem types, including Sequoia forests in the mid-montane Sierra Nevada. Understanding how winter cold and summer drought interact to produce the lush forest in the Sierra is critical to predicting the impacts of projected climate change on California's ecosystems, water supply, and carbon cycling. We investigated how smooth gradients of temperature and water availability produced sharp thresholds in biomass, productivity, growing season, water use, and ultimately ecosystem type and function. We used the climate gradient of the western slope of the Sierra Nevada as a study system. Four eddy covariance towers were situated in the major ecosystem types of the Sierra Nevada at approximately 800-m elevation intervals. Eddy flux data were combined with remote sensing and direct measurements of biomass, productivity, soil available water, and evapotranspiration to understand how weather and available water control ecosystem production and function. We found that production at the high elevation lodgepole site at 2700 m was strongly limited by winter cold. Production at the low elevation oak woodland site at 400 m was strongly limited by summer drought. The yellow pine site at 1200 m was only 4 °C cooler than the oak woodland site, yet had an order of magnitude more biomass and productivity with year-round growth. The mixed conifer site at 2000 m is 3.5 °C warmer than the lodgepole forest, yet also has higher biomass, ten times higher productivity, and year-round growth. We conclude that there is a broad climatological 'sweet spot' within the Sierra Nevada, in which the Mediterranean climate can support large-statured forest with high growth rates. The range of the mid-elevation forest was sharply bounded by water limitation at the lower edge and cold limitation at the upper edge despite small differences in precipitation and temperature across these boundaries. Our results suggest that small changes in precipitation or winter warming could markedly alter ecosystem structure and function as well as carbon and water cycling in the Sierra Nevada.

New constraints on the origin of the Sierra Madre de Chiapas (south Mexico) from sediment provenance and apatite thermochronometry

NASA Astrophysics Data System (ADS)

Witt, C.; Brichau, S.; Carter, A.

2012-12-01

The timing and source of deformation responsible for formation of the Sierra Madre de Chiapas (south Mexico) are unclear. To address this, apatite fission track and U-Th-He thermochronometry, combined with zircon U-Pb dating, were performed on bedrock and sedimentary samples of the Sierra Madre de Chiapas to discern timing of exhumation and identify sediment source areas. The U-Pb results show that Paleocene-Eocene terrigenous units outcropping at the northern section of the Sierra were mostly derived from Grenville (˜1 Ga) basement whereas the internal sections of the chain yield mainly Permian to Triassic ages (circa 270-230 Ma) typical of the Chiapas massif complex. Grenville-sourced sediments are most probably sourced by the Oaxacan block or the Guichicovi complex and were deposited to the north of the Sierra in a foreland setting related to a Laramide deformation front. Other possibly source areas may be related to metasedimentary units widely documented at the south Maya block such as the Baldi unit. The apatite fission track and U-Th-He data combined with previously published results record three main stages in exhumation history: (1) slow exhumation between 35 and 25 Ma affecting mainly the Chiapas massif complex; (2) fast exhumation between 16 and 9 Ma related to the onset of major strike-slip deformation affecting both the Chiapas massif complex and Chiapas fold-and-thrust belt; and (3) a 6 to 5 Ma period of rapid cooling that affected the Chiapas fold-and-thrust belt, coincident with the landward migration of the Caribbean-North America plate boundaries. These data suggest that most of the topographic growth of the Sierra Madre de Chiapas took place in the middle to late Miocene. The new thermochronological evidence combined with stratigraphic and kinematic information suggests that the left-lateral strike-slip faults bounding the Chiapas fold-and-thrust belt to the west may have accommodated most of the displacement between the North American and Caribbean plates during the last 6-5 Ma.

GPS Imaging suggests links between climate, magmatism, seismicity, and tectonics in the Sierra Nevada-Long Valley Caldera-Walker Lane system, western United States

NASA Astrophysics Data System (ADS)

Hammond, W. C.; Blewitt, G.; Kreemer, C.; Smith, K.

2017-12-01

The Walker Lane is a region of complex active crustal transtension in the western Great Basin of the western United States, accommodating about 20% of the 50 mm/yr relative motion between the Pacific and North American plates. The Long Valley caldera lies in the central Walker Lane in eastern California, adjacent to the eastern boundary of the Sierra Nevada/Great Valley microplate, and experiences intermittent inflation, uplift, and volcanic unrest from the magma chamber that resides at middle crustal depths. Normal and transform faults accommodating regional tectonic transtension pass by and through the caldera, complicating the interpretation of the GPS-measured strain rate field, estimates of fault slip rates, and seismic hazard. Several dozen continuously recording GPS stations measure strain and uplift in the area with mm precision. They observe that the most recent episode of uplift at Long Valley began in mid-2011, continuing until late 2016, raising the surface by 100 mm in 6 years. The timing of the initiation of uplift coincides with the beginning of severe drought in California. Furthermore, the timing of a recent pause in uplift coincides with the very wet 2016-2017 winter, which saw approximately double normal snow pack. In prior studies, we showed that the timing of changes in geodetically measured uplift rate of the Sierra Nevada coincides with the timing of drought conditions in California, suggesting a link between hydrological loading and Sierra Nevada elevation. Here we take the analysis three steps further to show that changes in Sierra Nevada uplift rate coincide in time with 1) enhanced inflation at the Long Valley caldera, 2) shifts in the patterns and rates of horizontal tensor strain rate, and 3) seismicity patterns in the central Walker Lane. We use GPS solutions from the Nevada Geodetic Laboratory and the new GPS Imaging technique to produce robust animations of the time variable strain and uplift fields. The goals of this work are to document links between climate, Sierra Nevada uplift rates, response of the magmatic system, and seismicity in the Central Walker Lane, and to explore the physical mechanisms that may be behind these correlations.

Seismicity patterns during a period of inflation at Sierra Negra volcano, Galápagos Ocean Island Chain

NASA Astrophysics Data System (ADS)

Davidge, Lindsey; Ebinger, Cynthia; Ruiz, Mario; Tepp, Gabrielle; Amelung, Falk; Geist, Dennis; Coté, Dustin; Anzieta, Juan

2017-03-01

Basaltic shield volcanoes of the western Galápagos islands are among the most rapidly deforming volcanoes worldwide, but little was known of the internal structure and brittle deformation processes accompanying inflation and deflation cycles. A 15-station broadband seismic array was deployed on and surrounding Sierra Negra volcano, Galápagos from July 2009 through June 2011 to characterize seismic strain patterns during an inter-eruption inflation period and to evaluate single and layered magma chamber models for ocean island volcanoes. We compare precise earthquake locations determined from a 3D velocity model and from a double difference cluster method. Using first-motion of P-arrivals, we determine focal mechanisms for 8 of the largest earthquakes (ML ≤ 1.5) located within the array. Most of the 2382 earthquakes detected by the array occurred beneath the broad (∼9 km-wide) Sierra Negra caldera, at depths from surface to about 8 km below sea level. Although outside our array, frequent and larger magnitude (ML ≤ 3.4) earthquakes occurred at Alcedo and Fernandina volcano, and in a spatial cluster beneath the shallow marine platform between Fernandina and Sierra Negra volcanoes. The time-space relations and focal mechanism solutions from a 4-day long period of intense seismicity June 4-9, 2010 along the southeastern flank of Sierra Negra suggests that the upward-migrating earthquake swarm occurred during a small volume intrusion at depths 5-8 km subsurface, but there was no detectable signal in InSAR data to further constrain geometry and volume. Focal mechanisms of earthquakes beneath the steep intra-caldera faults and along the ring fault system are reverse and strike-slip. These new seismicity data integrated with tomographic, geodetic, and petrological models indicate a stratified magmatic plumbing system: a shallow sill beneath the large caldera that is supplied by magma from a large volume deeper feeding system. The large amplitude inter-eruption inflation of the shallow sill beneath the Sierra Negra caldera is accompanied by only very small magnitude earthquakes, although historical records indicate that larger magnitude earthquakes (Mw <6) occur during eruptions, trapdoor faulting episodes without eruptions, and large volume flank intrusions.

Distance, accessibility and costs. Decision-making during childbirth in rural Sierra Leone: A qualitative study.

PubMed

Treacy, Laura; Bolkan, Håkon A; Sagbakken, Mette

2018-01-01

Sierra Leone has one of the highest maternal mortality ratios in the world. Efforts to reduce maternal mortality have included initiatives to encourage more women to deliver at health facilities. Despite the introduction of the free health care initiative for pregnant women, many women still continue to deliver at home, with few having access to a skilled birth attendant. In addition, inequalities between rural and urban areas in accessing and utilising health facilities persist. Further insight into how and why women make decisions around childbirth will help guide future plans and initiatives in improving maternal health in Sierra Leone. The objective of this study was to explore the perceptions and decision-making processes of women and their communities during childbirth in rural Sierra Leone. Data were collected through seven focus group discussions and 22 in-depth interviews with recently pregnant women and their community members in two rural villages. Data were analysed using systematic text condensation. Findings revealed that decision-making processes during childbirth are dynamic, intricate and need to be understood within the broader social context that they take place. Factors such as distance and lack of transport, perceived negative behaviour of hospital staff, direct and indirect financial obstacles, as well as the position of women in society all interact and influence how and what decisions are made. Pregnant women face multiple interacting vulnerabilities that influence their healthcare-seeking decisions during pregnancy and childbirth. Future initiatives to improve access and utilisation of safe healthcare services for pregnant women need to be based on adequate knowledge of structural constraints and health inequities that affect women in rural Sierra Leone.

Phylogeography and historical demography of the Pacific Sierra mackerel (Scomberomorus sierra) in the Eastern Pacific

PubMed Central

2010-01-01

Background Testing connectivity among populations of exploited marine fish is a main concern for the development of conservation strategies. Even though marine species are often considered to display low levels of population structure, barriers to dispersal found in the marine realm may restrict gene flow and cause genetic divergence of populations. The Pacific Sierra mackerel (Scomberomorus sierra) is a pelagic fish species distributed throughout the tropical and subtropical waters of the eastern Pacific. Seasonal spawning in different areas across the species range, as well as a limited dispersal, may result in a population genetic structure. Identification of genetically discrete units is important in the proper conservation of the fishery. Results Samples collected from the Eastern Pacific, including the areas of main abundance of the species, presented high levels of mtDNA genetic diversity and a highly significant divergence. At least two genetically discrete groups were detected in the northern (Sinaloa) and central areas (Oaxaca and Chiapas) of the species range, exhibiting slight genetic differences with respect to the samples collected in the southern region (Peru), together with a "chaotic genetic patchiness" pattern of differentiation and no evidence of isolation by distance. Historical demographic parameters supported the occurrence of past population expansions, whereas the divergence times between populations coincided with the occurrence of glacial maxima some 220 000 years ago. Conclusions The population genetic structure detected for the Pacific Sierra mackerel is associated with a limited dispersal between the main abundance areas that are usually linked to the spawning sites of the species. Population expansions have coincided with glacial-interglacial episodes in the Pleistocene, but they may also be related to the increase in the SST and with upwelling areas in the EEP since the early Pleistocene. PMID:20438637

Gallstone disease in Peruvian coastal natives and highland migrants

PubMed Central

Moro, P; Checkley, W; Gilman, R; Cabrera, L; Lescano, A; Bonilla, J; Silva, B

2000-01-01

BACKGROUND—In a previous study, we found that gallstones were a common occurrence in the high altitude villages of the Peruvian Andes.
AIMS—To determine if high altitude (⩾ 1500 m) is a contributing risk factor for gallstone disease.
METHODS—We conducted a cross sectional study in a periurban community in Lima, Peru, and compared the prevalence of gallstone disease between coastal natives, highland (Sierra) natives and Sierra natives who had migrated to the coast. We also compared the prevalence rates from this study with those from a previous study conducted at high altitude. We examined 1534 subjects >15 years of age for gallstone disease. Subjects were interviewed for the presence or absence of risk factors.
RESULTS—Gallstone disease was more common in females (16.1 cases per 100, 95% CI 13.8-18.2) than in males (10.7 per 100, 95% CI 8.0-13.4). Females had a greater risk of gallstone disease, especially if they had used oral contraception and/or had four or more children. The age adjusted prevalence was not significantly different between coastal natives, Sierra migrants, and Andean villagers. The prevalence of gallstone disease was not associated with time since migration or with having native Sierra parents. After adjusting for other risk factors, Sierra natives who migrated to the coast had a lower prevalence of gallstone disease than coastal natives (odds ratio 0.74, 95% CI 0.58-0.94).
CONCLUSIONS—This study indicates that high altitude is not a positive risk factor for gallstone disease and confirms that this disease is common in Peruvians, which may be attributable to Peruvian-Indian ethnicity.


Keywords: gallstone disease; cholelithiasis; high altitude; risk factors; epidemiology; Peru PMID:10716689

Snowpack Estimates Improve Water Resources Climate-Change Adaptation Strategies

NASA Astrophysics Data System (ADS)

Lestak, L.; Molotch, N. P.; Guan, B.; Granger, S. L.; Nemeth, S.; Rizzardo, D.; Gehrke, F.; Franz, K. J.; Karsten, L. R.; Margulis, S. A.; Case, K.; Anderson, M.; Painter, T. H.; Dozier, J.

2010-12-01

Observed climate trends over the past 50 years indicate a reduction in snowpack water storage across the Western U.S. As the primary water source for the region, the loss in snowpack water storage presents significant challenges for managing water deliveries to meet agricultural, municipal, and hydropower demands. Improved snowpack information via remote sensing shows promise for improving seasonal water supply forecasts and for informing decadal scale infrastructure planning. An ongoing project in the California Sierra Nevada and examples from the Rocky Mountains indicate the tractability of estimating snowpack water storage on daily time steps using a distributed snowpack reconstruction model. Fractional snow covered area (FSCA) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data were used with modeled snowmelt from the snowpack model to estimate snow water equivalent (SWE) in the Sierra Nevada (64,515 km2). Spatially distributed daily SWE estimates were calculated for 10 years, 2000-2009, with detailed analysis for two anamolous years, 2006, a wet year and 2009, an over-forecasted year. Sierra-wide mean SWE was 0.8 cm for 01 April 2006 versus 0.4 cm for 01 April 2009, comparing favorably with known outflow. Modeled SWE was compared to in-situ (observed) SWE for 01 April 2006 for the Feather (northern Sierra, lower-elevation) and Merced (central Sierra, higher-elevation) basins, with mean modeled SWE 80% of observed SWE. Integration of spatial SWE estimates into forecasting operations will allow for better visualization and analysis of high-altitude late-season snow missed by in-situ snow sensors and inter-annual anomalies associated with extreme precipitation events/atmospheric rivers. Collaborations with state and local entities establish protocols on how to meet current and future information needs and improve climate-change adaptation strategies.

El Morro caldera (33° 10‧ S, 66° 24‧ W), San Luis, Argentina: An exceptional case of fossil pre-collapse updoming

NASA Astrophysics Data System (ADS)

Sruoga, P.; Ibañes, O. D.; Japas, M. S.; Urbina, N. E.

2017-05-01

Volcanism at Sierra del Morro represents the final stages of the flat-slab related magmatism in the easternmost San Luis Neogene Volcanic Belt. This 80 km-long NW-WNW-trending belt tracks the episodic inland migration of both magmatism and tectonic deformation since 18 Ma. The Sierra del Morro stands out in the Eastern Sierras Pampeanas as a metamorphic block uplifted during the Late Miocene-Pleistocene by a combination of magma injection and tectonic deformation. Although sequences that preserve stages of basement updoming are not often preserved, exposures in Sierra del Morro are exception in providing key evidence and insight into the involved processes. Based on the comprehensive study of volcanic stratigraphy and structures, the reconstruction of the volcanic architecture has been carried out. We infer a three stage evolution of the El Morro caldera as follows: 1) pre-collapse updoming and volcanism, 2) collapse caldera formation and 3) post-caldera volcanism. The ascent of magma is recorded in small tumescence sites, strongly controlled by oblique transtensional WNW-NW and ENE-striking brittle-ductile megashear zones. Even though the area affected by tumescence was large, magma injection progressed only locally. At Cerros Guanaco and Pampa, metamorphic rocks were updomed and strongly brecciated, whereas at Sierra del Morro magma was emplaced as pre-collapse domes with associated block-and-ash flows, ignimbrite caldera-forming eruptions and post-caldera lava domes and dykes. The caldera is located in the intersection of two major oblique transtensional WNW-NW and ENE-trending brittle-ductile megashear zones, where the highest positive dilatation occurred.

Nationally representative household survey of surgery and mortality in Sierra Leone.

PubMed

Kwon, Steve; Groen, Reinou S; Kamara, Thaim B; Cassidy, Laura D; Samai, Mohamed; Yambasu, Sahr E; Kushner, Adam L

2013-08-01

There is limited evidence to characterize the burden of unmet need of surgical diseases in low- and middle-income countries. The purpose of this study was to determine rate of deaths attributable to a surgical condition and reasons for not seeking surgical care in Sierra Leone. The Surgeons OverSeas Assessment of Surgical Need (SOSAS) is a survey tool developed collaboratively to be used for cross-sectional data collection of the prevalence of surgical conditions in any country. A population-weighted cluster-sample household survey was conducted throughout Sierra Leone in 2012 using the SOSAS survey tool. Total of 1,840 households (11,870 individuals) were sampled, yielding a 98.3 % response rate. Overall, there were 709 total deaths reported (6.0 %). The mean age at death was 36.4 ± 30.1 years: 330 (46.6 %) were female. Most deaths occurred at home (58.1 % vs. 34.1 % in hospitals). Of the 709 deaths, 237 (33.4 %) were associated with conditions included in our predefined surgical disease category. Abdominal distension/pain was the most commonly associated surgical condition (13.9 %) followed by perinatal bleeding/illness (6.0 %). Among the 237 with surgical conditions, 51 (21.9 %) did not seek medical care, most commonly because of a lack of money (35.3 %) or inability to provide timely care (37.3 %). A large proportion of deaths in Sierra Leone was associated with surgical conditions, the majority of which did not undergo surgical intervention. Our results indicate that to remove barriers to effective surgical care in Sierra Leone policymakers should first focus on relieving financial burdens and increasing access to timely surgical care.

Methodology and results of calculating central California surface temperature trends: Evidence of human-induced climate change?

USGS Publications Warehouse

Christy, J.R.; Norris, W.B.; Redmond, K.; Gallo, K.P.

2006-01-01

A procedure is described to construct time series of regional surface temperatures and is then applied to interior central California stations to test the hypothesis that century-scale trend differences between irrigated and nonirrigated regions may be identified. The procedure requires documentation of every point in time at which a discontinuity in a station record may have occurred through (a) the examination of metadata forms (e.g., station moves) and (b) simple statistical tests. From this "homogeneous segments" of temperature records for each station are defined. Biases are determined for each segment relative to all others through a method employing mathematical graph theory. The debiased segments are then merged, forming a complete regional time series. Time series of daily maximum and minimum temperatures for stations in the irrigated San Joaquin Valley (Valley) and nearby nonirrigated Sierra Nevada (Sierra) were generated for 1910-2003. Results show that twentieth-century Valley minimum temperatures are warming at a highly significant rate in all seasons, being greatest in summer and fall (> +0.25??C decade-1). The Valley trend of annual mean temperatures is +0.07?? ?? 0.07??C decade-1. Sierra summer and fall minimum temperatures appear to be cooling, but at a less significant rate, while the trend of annual mean Sierra temperatures is an unremarkable -0.02?? ?? 0.10??C decade-1. A working hypothesis is that the relative positive trends in Valley minus Sierra minima (>0.4??C decade-1 for summer and fall) are related to the altered surface environment brought about by the growth of irrigated agriculture, essentially changing a high-albedo desert into a darker, moister, vegetated plain. ?? 2006 American Meteorological Society.

Improving access to surgery in a developing country: experience from a surgical collaboration in Sierra Leone.

PubMed

Kushner, Adam L; Kamara, Thaim B; Groen, Reinou S; Fadlu-Deen, Betsy D; Doah, Kisito S; Kingham, T Peter

2010-01-01

Although surgery is increasingly recognized as an essential component of primary health care, there has been little documentation of surgical programs in low- and middle-income countries. Surgeons OverSeas (SOS) is a New York-based organization with a mission to save lives in developing countries by improving surgical care. This article highlights the surgical program in Sierra Leone as a possible model to improve access to surgery. An SOS team conducted a needs assessment of surgical capacity in Sierra Leone in February 2008. Interventions were then developed and programs were implemented. A follow-up assessment was conducted in December 2009, which included interviews of key Sierra Leone hospital personnel and a review of operating room log books. Based on an initial needs assessment, a program was developed that included training, salary support, and the provision of surgical supplies and equipment. Two 3-day workshops were conducted for a total of 44 health workers, salary support given to over 100 staff, and 2 containers of supplies and equipment were donated. Access to surgery, as measured by the number of major operations at Connaught Hospital, increased from 460 cases in 2007 to 768 cases in 2009. The SOS program in Sierra Leone highlights a method for improving access to surgery that incorporates an initial needs assessment with minimal external support and local staff collaboration. The program functions as a catalyst by providing training, salary support, and supplies. The beneficial results of the program can then be used to advocate for additional resources for surgery from policy makers. This model could be beneficial in other resource-poor countries in which improved access to surgery is desired. Copyright 2010 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Exposure of a late cretaceous layered mafic-felsic magma system in the central Sierra Nevada batholith, California

USGS Publications Warehouse

Coleman, D.S.; Glazner, A.F.; Miller, J.S.; Bradford, K.J.; Frost, T.P.; Joye, J.L.; Bachl, C.A.

1995-01-01

New U-Pb zircon ages for the Lamarck Granodiorite, associated synplutonic gabbro and diorite plutons, and two large mafic intrusive complexes that underlie them in the Sierra Nevada batholith are 92??1 Ma. These ages establish the Late Cretaceous as a period of extensive mafic-felsic magmatism in the central part of the batholith, and confirm the significance of mafic magmatism in the evolution of the voluminous silicic plutions in the Sierran arc. The lack of significant zircon inheritance in any of the units analyzed supports isotopic evidence that the Lamarck and other Late Cretaceous Sierran plutons were derived predominantly from young crust. Recognition of an extensive mafic-felsic magma system in the Sierra Nevada batholith emphasizes the importance of basaltic liquids in the evolution of continental crust in arc settings. ?? 1995 Springer-Verlag.

Drill-hole data, drill-site geology, and geochemical data from the study of Precambrian uraniferous conglomerates of the Medicine Bow Mountains and Sierra Madre of southeastern Wyoming

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karlstrom, K.E.; Houston, R.S.; Schmidt, T.G.

1981-02-01

This volume is presented as a companion to Volume 1: The Geology and Uranium Potential of Precambrian Conglomerates in the Medicine Bow Mountains and Sierra Madre of Southeastern Wyoming; and to Volume 3: Uranium Assessment for Precambrian Pebble Conglomerates in Southeastern Wyoming. Volume 1 summarized the geologic setting and geologic and geochemical characteristics of uranium-bearing conglomerates in Precambrian metasedimentary rocks of southeastern Wyoming. Volume 3 is a geostatistical resource estimate of U and Th in quartz-pebble conglomerates. This volume contains supporting geochemical data, lithologic logs from 48 drill holes in Precambrian rocks of the Medicine Bow Mountains and Sierra Madre,more » and drill site geologic maps and cross-sections from most of the holes.« less

Preliminary report on radioactive conglomerates of Middle Precambrian age in the Sierra Madre and Medicine Bow Mountains of southeastern Wyoming

USGS Publications Warehouse

Houston, Robert Stroud; Graff, P.J.; Karlstrom, K.E.; Root, Forrest

1977-01-01

Middle Precambrian miogeosynclinal metasedimentary rocks o# the Sierra Madre and Medicine Bow Mountains of southeastern Wyoming contain radioactive quartz-pebble conglomerates of possible economic interest. These conglomerates do not contain ore-grade uranium in surface outcrops, but an earlier report on the geochemistry of the Arrastre Lake area of the Medicine Bow Mountains shows that ore-grade deposits may be present in the subsurface. This report describes the stratigraphy of the host metasedimentary rocks and the stratigraphic setting of the radioactive conglomerates in both the Sierra Madre and Medicine Bow Mountains, and compares these rock units with those of the Blind River-Elliot Lake uranium district in Canada. The location of radioactive .conglomerates is given so that further exploration may be undertaken by interested parties.

Exceptional suffering? Enumeration and vernacular accounting in the HIV-positive experience.

PubMed

Benton, Adia

2012-01-01

Drawing on 17 months of ethnographic fieldwork in Freetown, Sierra Leone, I highlight the recursive relationship between Sierra Leone as an exemplary setting and HIV as an exceptional disease. Through this relationship, I examine how HIV-positive individuals rely on both enumerative knowledge (seroprevalence rates) and vernacular accounting (NGO narratives of vulnerability) to communicate the uniqueness of their experience as HIV sufferers and to demarcate the boundaries of their status. Various observers' enumerative and vernacular accounts of Sierra Leone's decade-long civil conflict, coupled with global health accounts of HIV as exceptional, reveal the calculus of power through which global health projects operate. The contradictions between the exemplary and the exceptional-and the accompanying tension between quantitative and qualitative facts-are mutually constituted in performances and claims made by HIV-positive individuals themselves.

Trauma Healing in Refugee Camps in Guinea: A Psychosocial Program for Liberian and Sierra Leonean Survivors of Torture and War

ERIC Educational Resources Information Center

Stepakoff, Shanee; Hubbard, Jon; Katoh, Maki; Falk, Erika; Mikulu, Jean-Baptiste; Nkhoma, Potiphar; Omagwa, Yuvenalis

2006-01-01

From 1999 to 2005, the Minneapolis-based Center for Victims of Torture (CVT) served Liberian and Sierra Leonean survivors of torture and war living in the refugee camps of Guinea. A psychosocial program was developed with 3 main goals: (1) to provide mental health care; (2) to train local refugee counselors; and (3) to raise community awareness…

Courtright intrusive zone: Sierra National Forest, Fresno County, California.

USGS Publications Warehouse

Bateman, P.C.; Kistler, R.W.; DeGraff, J.V.

1984-01-01

This is a field guide to a well-exposed area of plutonic and metamorphic rocks in the Sierra National Forest, Fresno County, California. The plutonic rocks, of which three major bodies are recognized, besides aplite and pegmatite dykes, range 103 to approx 90 m.y. in age. Points emphasized include cataclastic features within the plutonic rocks, schlieren and mafic inclusions. (M.A. 83M/0035).-A.P.

Estimating contribution of wildland fires to ambient ozone levels in National Parks in the Sierra Nevada, California

Treesearch

Haiganoush K. Preisler; Shiyuan (Sharon) Zhong; Annie Esperanza; Timothy J. Brown; Andrzej Bytnerowicz; Leland Tarnay

2010-01-01

Data from four continuous ozone and weather monitoring sites operated by the National Park Service in Sierra Nevada, California, are used to develop an ozone forecasting model and to estimate the contribution of wildland fires on ambient ozone levels. The analyses of weather and ozone data pointed to the transport of ozone precursors from the Central Valley as an...

Surface motion of active rock glaciers in the Sierra Nevada, California, USA: inventory and a case study using InSAR

Treesearch

L. Liu; C.I. Millar; R.D. Westfall; H.A. Zebker

2013-01-01

Despite the abundance of rock glaciers in the Sierra Nevada of California, USA, few efforts have been made to measure their surface flow. Here we use the interferometric synthetic aperture radar (InSAR) technique to compile a~benchmark inventory describing the kinematic state of 59 active rock glaciers in this region. Statistically, these rock glaciers moved at...

Fluctuating populations of house wrens and Bewick's wrens in foothills of the western Sierra Nevada of California

Treesearch

Jared Verner; Kathryn L. Purcell

1999-01-01

In foothills of the western Sierra Nevada, 31 km east of Madera, California, we studied whether Bewick's Wrens (Thryomanes bewickii) tend to be excluded from an area occupied by House Wrens (Troglodytes aedon) as reported in several studies in the eastern United States. Neither point counts from 1985 to 1997 nor spot mapping from 1989 to 1993 suggests any...

Undiagnosed Acute Viral Febrile Illnesses, Sierra Leone

DTIC Science & Technology

2014-07-01

Sierra Leone in West Africa is in a Lassa fever – hyperendemic region that also includes Guinea and Li- beria. Each year...suspected Lassa fever cases result in submission of ≈500–700 samples to the Kenema Govern- ment Hospital Lassa Diagnostic Laboratory in eastern Si- erra...patients have acute diseases of unknown origin. To investigate what other ar- thropod-borne and hemorrhagic fever viral diseases might cause serious

Preliminary investigation of exceptionally strong winds in mountainous areas of New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reynolds, R.D.; Barnett, K.M.

1980-10-01

The mean wind speed in four mountainous areas in New Mexico were sampled for one year using wind data accumulators. The sites studied were: (1) San Augustin Pass, 15 miles northeast of Las Cruces; (2) Sierra Grande, an isolated peak midway between Raton and Clayton; (3) Buck Mountain, 10 miles northeast of Sierra Blanca Peak near Ruidoso, and (4) Palomas Mesa, 20 miles west-southwest of Tucumcari.

Groundwater quality in the Sierra Nevada, California

USGS Publications Warehouse

Fram, Miranda S.; Belitz, Kenneth

2014-01-01

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project (PBP) of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. The Sierra Nevada Regional study unit constitutes one of the study units being evaluated.

Nitrogen content of Letharia vulpina tissue from forests of the Sierra Nevada, California: geographic patterns and relationships to ammonia estimates and climate

Treesearch

Sarah Jovan; Tom Carlberg

2007-01-01

Nitrogen (N) pollution is a growing concern in forests of the greater Sierra Nevada, which lie downwind of the highly populated and agricultural Central Valley. Nitrogen content of Letharia vulpina tissue was analyzed from 38 sites using total Kjeldahl analysis to provide a preliminary assessment of N deposition patterns. Collections were co-located with plots where...

Content of chemical elements in tree rings of lodgepole pine and whitebark pine from a subalpine Sierra Nevada forest

Treesearch

David L. Peterson; Darren R. Anderson

1990-01-01

The wood of lodgepole pines and whitebark pines from a high elevation site in the east central Sierra Nevada of California was analyzed for chemical content to determine whether there were any temporal patterns of chemical distribution in tree rings. Cores were taken from 10 trees of each species and divided into 5-year increments for chemical analysis. Correlation...

Mountain lions: preliminary findings on home-range use and density, central Sierra Nevada

Treesearch

Donald L. Neal; George N. Steger; Ronald C. Bertram

1987-01-01

Between August 1983 and December 1985, 19 mountain lions were captured, radio equipped, and monitored daily within a portion of the North Kings deer herd range on the west slope of the central Sierra Nevada in California. The density of adult mountain lions was estimated to be one per 33.3 km²; that of adults and kittens together was estimated to be one per 20...

Ecology of the Scorpion, Microtityus jaumei in Sierra de Canasta, Cuba

PubMed Central

Cala-Riquelme, Franklyn; Colombo, Marco

2011-01-01

An assessment of the population dynamics of Microtityus jaumei Armas (Scorpiones: Buthidae) on the slopes south of Sierra de Canasta, Guantánamo Province, Cuba show an increase in activity over the year (≤ 0.05). The activity peak is related to the reproductive period from June to November. The abundance of scorpions was significantly related to density of the canopy and thickness of the substrate. PMID:21870972

Characteristics of nest trees and nest sites of California spotted owls in coniferous forests of the southern Sierra Nevada

Treesearch

George N. Steger; Thomas E. Munton; Kenneth D. Johnson; Gary E. Eberlein

1997-01-01

We described 86 nest sites of California spotted owl (Sh-ix occidentalis occrdentalzs) and tested for differences in vegetation structure at nest locations rn conifer-dominated stands in 2 study areas, the Sierra National Forest (SNF) and Sequoia and Kings Canyon National Parks (SNP), California. All nests were between 1061 and 2414 m in elevation, 52 were side-cavity...

EFFECTS OF CLIMATE VARIABILITY ON THE CARBON DIOXIDE, WATER, AND SENSIBLE HEAT FLUXES ABOVE A PONDEROSA PINE PLANTATION IN THE SIERRA NEVADA, CA. (R826601)

EPA Science Inventory

Abstract

Fluxes of CO₂, water vapor, and sensible heat were measured by the eddy covariance method above a young ponderosa pine plantation in the Sierra Nevada Mountains (CA) over two growing seasons (1 June_¯10 September 1997 and 1 May_&#...

Ecology of the scorpion, Microtityus jaumei in Sierra de Canasta, Cuba.

PubMed

Cala-Riquelme, Franklyn; Colombo, Marco

2011-01-01

An assessment of the population dynamics of Microtityus jaumei Armas (Scorpiones: Buthidae) on the slopes south of Sierra de Canasta, Guantánamo Province, Cuba show an increase in activity over the year (≤ 0.05). The activity peak is related to the reproductive period from June to November. The abundance of scorpions was significantly related to density of the canopy and thickness of the substrate.

An Examination of Primary School Attendance and Completion among Secondary School Age Adolescents in Post-Conflict Sierra Leone

ERIC Educational Resources Information Center

Moyi, Peter

2013-01-01

Sierra Leone was ravaged by a civil war between 1991 and 2002. Since the end of the war, it has witnessed an unprecedented increase in school enrollments. Although school enrollment has increased, the number of school age children who are out of school remains high. The focus of international agencies is on children of primary school age, yet a…

Does Community Poverty Reduce Children's School Attendance More at Primary Education than at Secondary Education? Evidence from Post-Conflict Sierra Leone

ERIC Educational Resources Information Center

Kamanda, Mamusu

2016-01-01

In Sierra Leone, the number of primary schools is almost seven times more than junior-secondary schools (JSS). Living in a poor community has been shown to reduce children's school attendance because of lower access and poorer quality of education in these communities. However, it is unclear whether living in a poor community reduces attendance at…

78 FR 79688 - Newmont Nevada Energy Investment LLC v. Sierra Pacific Power Company; Notice of Complaints

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-31

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL14-16-000] Newmont Nevada Energy Investment LLC v. Sierra Pacific Power Company; Notice of Complaints Take notice that on December 23, 2013, pursuant to sections 206 and 306 of the Federal Power Act (FPA), 16 U.S.C. 824e, and 825e and Rule 206 of the Rules of Practice and...

The Role of Non-Governmental Organisations and Faith-Based Organisations in Achieving Education for All: The Case of Sierra Leone

ERIC Educational Resources Information Center

Nishimuko, Mikako

2009-01-01

Sierra Leone, one of the world's poorest countries, experienced a civil war from 1991 to 2002. The government's capacity to provide educational services remains weak, and still over 30% of children in the country are hard to reach and do not have access to primary education. This paper discusses the role of non-governmental organisations (NGOs)…

Recent projections of 21st-century climate change and watershed responses in the Sierra Nevada

Treesearch

Michael D. Dettinger; Daniel R. Cayan; Noah Knowles; Anthony Westerling; Mary K. Tyree

2004-01-01

In the near future, the Sierra Nevada’s climate is projected to experience a new form of climate change due to increasing concentrations of greenhouse gases in the global atmosphere from the burning of fossil fuels and other human activities. If the changes occur, they presumably will be added to the large interannual and longer-term climate variations in the recent...

Forty years of land use and land ownership change in central Sierra Nevada oak woodlands

Treesearch

Matt Wacker; David Saah; Louise Fortmann

2002-01-01

The vast majority of California’s oak woodlands are privately owned, and, therefore, highly susceptible to changes in land use and ownership as well as land fragmentation. This is particularly true in the Central Sierra Nevada, where significant changes in land use have occurred during the past 40 years. Perhaps no location illustrates this trend better than the...

Site index curves for young-growth California white fir on the western slopes of the Sierra Nevada

Treesearch

K. Leroy Dolph

1987-01-01

Site index curves for young-growth California white fir were developed by using stem analysis data from 77 dominant and codominant trees growing in mixed-coniferstands on the western slopes of the Sierra Nevada. Site index reference age is 50 years at breast height. A family of 11 curves is presented for site index estimation. For more precise estimates, the site index...

Soil nutrients and microbial activity after early and late season prescribed burns in a Sierra Nevada mixed conifer forest

Treesearch

Sarah T. Hamman; Ingrid C. Burke; Eric E. Knapp

2008-01-01

Restoring the natural fire regime to forested systems that have experienced fire exclusion throughout the past century can be a challenge due to the heavy fuel loading conditions. Fire is being re-introduced to mixed conifer forests in the Sierra Nevada through both early season and late season prescribed burns, even though most fires historically occurred in the late...

Genetic diversity, mating system, and conservation of a Mexican subalpine relict, Picea mexicana Martínez

Treesearch

F. Thomas Ledig; Paul D. Hodgskiss; Virginia Jacob-Cervantes

2002-01-01

Mexican spruce (Picea mexicana Martínez), an endangered species of the highest sky islands in México’s Sierra Madre Oriental and Sierra Madre Occidental, is threatened by fire, grazing, and global warming. Its conservation depends on whether it also is threatened by inbreeding and loss of genic diversity. We used 18 isozyme markers in 12 enzyme...

Tree mortality from fire and bark beetles following early and late season prescribed fires in a Sierra Nevada mixed conifer forest

Treesearch

Dylan W. Schwilk; Eric E. Knapp; Scott M. Ferrenberg; Jon E. Keeley; Anthony. Caprio

2006-01-01

Over the last century, fire exclusion in the forests of the Sierra Nevada has allowed surface fuels to accumulate and has led to increased tree density. Stand composition has also been altered as shade tolerant tree species crowd out shade intolerant species. To restore forest structure and reduce the risk of large, intense fires, managers have increasingly used...

Fire decreases arthropod abundance but increases diversity: early and late season prescribed fire effects in a Sierra Nevada mixed-conifer forest

Treesearch

Scott M. Ferrenberg; Dylan W. Schwilk; Eric E. Knapp; Eric Groth; Jon E. Keeley

2006-01-01

Prior to fire suppression in the 20th century, the mixed-conifer forests of the Sierra Nevada, California, U.S.A., historically burned in frequent fires that typically occurred during the late summer and early fall. Fire managers have been attempting to restore natural ecosystem processes through prescription burning, and have often favored burning during the fall in...

Truckee Meadows (Reno-Sparks Metropolitan Area) Nevada: Feasibility Report and Environmental Impact Statement

DTIC Science & Technology

1985-02-01

of Art and the Community Concert Association. 6. Education. Washoe County is served by 42 elementary schools , 9 middle schools (grades 6 through 8...Cultural Opportunities. Cultural opportunities have expanded since formation of the Sierra Nevada Arts Foundation. Organized in 1971, the foundation...serves as the headquarters for development and promotion of the arts . Cultural groups associated with the foundation include the Sierra Nevada Museum

Assessment of post-fire forest structural diversity using neighborhood parameter in the Sierra Madre Oriental, Mexico

Treesearch

Diana Yemilet Avila Flores; Marco Aurelio González Tagle; Javier Jiménez Pérez; Oscar Aguirre Calderón; Eduardo Treviño Garza

2013-01-01

The objective of this research was to characterize the spatial structure patterns of a Pinus hartwegii forest in the Sierra Madre Oriental, affected by a fire in 1998. Sampling was stratified by fire severity. A total of three fire severity classes (low, medium and high) were defined. Three sample plots of 40m x 40m were established for each...

Climate, rain shadow, and human-use influences on fire regimes in the eastern Sierra Nevada, California, USA

Treesearch

M.P. North; K.M. van de Water; S.L. Stephens; B.M. Collins

2009-01-01

There have been few fire history studies of eastern Sierra Nevada forests in California, USA, where a steep elevation gradient, rain shadow conditions, and forest stand isolation may produce different fire regimes than those found on the range’s western slope. We investigated historic fire regimes and potential climate influences on four forest types ranging in...

Potential climatic refugia in semi-arid, temperate mountains: plant and arthropod assemblages associated with rock glaciers, talus slopes, and their forefield wetlands, Sierra Nevada, California, USA

Treesearch

Constance I. Millar; Robert D. Westfall; Angela Evenden; Jeffrey G. Holmquist; Jutta Schmidt-Gengenbach; Rebecca S. Franklin; Jan Nachlinger; Diane L. Delany

2015-01-01

Unique thermal and hydrologic regimes of rock-glacier and periglacial talus environments support little-studied mountain ecosystems. We report the first studies of vascular plant and arthropod diversity for these habitats in the central Sierra Nevada, California, USA. Surfaces of active rock glaciers develop scattered islands of soil that provide habitat for vegetation...

Medium and large mammals in the Sierra La Madera, Sonora, Mexico

Treesearch

Erick Oswaldo Bermudez-Enriquez; Rosa Elena Jimenez-Maldonado; Gertrudis Yanes-Arvayo; Maria de la Paz Montanez-Armenta; Hugo Silva-Kurumiya

2013-01-01

Sierra La Madera is a Sky Island mountain range in the Madrean Archipelago. It is in Fracción V of the Ajos-Bavispe CONANP Reserve in the Municipios (= Counties) of Cumpas, Granados, Huásabas, Moctezuma, and Villa Hidalgo. Medium and large mammals were inventoried using camera traps. Eighteen Wild View 2® camera traps were deployed during four sampling periods: August...

Short-term effects of fire and forest thinning on truffle abundance and consumption by Neotamias speciosus in the Sierra Nevada of California

Treesearch

Marc D. Meyer; Malcolm P. North; Douglas A. Kelt

2005-01-01

In many western North American forests, prescribed burning and mechanical thinning are widely used to reduce fuels and restore stand conditions after a century of fire suppression. Few studies have followed the relative impacts of these treatments on the production and consumption of truffles in forest ecosystems, particularly in the Sierra Nevada of California. Using...

Genetic studies of Northern Goshawks (Accipiter gentilis): genetic tagging and individual identification from feathers, and determining phylogeography, gene flow and population history for Goshawks in North America

Treesearch

Shelley Bayard de Volo

2008-01-01

The Northern Goshawk (Accipiter gentilis) is a large, highly mobile, mostly nonmigratory and widespread forest raptor. It ranges across the Boreal forests from Alaska to Newfoundland, and south into forests of the Great Lakes, and montane regions of the Appalachian, Cascade, Sierra Nevada, Rocky Mountain, and Sierra Madre Occidental.

Monitoring the effects of air-quality on forests: An overview of the Sierra Ancha Experimental Forest ICP-Level II Site

Treesearch

Peter E. Koestner; Karen A. Koestner; Daniel G. Neary

2012-01-01

The Sierra Ancha International Cooperative Program on Assessment and Monitoring of Air Pollution Effects on Forests study site or (SAEF-ICP II) is part of an international network of cooperative forest monitoring sites spread throughout Europe and the United States. The United Nations Economic Commission for Europe established the ICP II network in 1985 to monitor long...

Effects of non-native trout on Pacific treefrogs (Hyla regilla) in the Sierra Nevada.

Treesearch

K.R. Matthews; K.L. Pope; H. K. Preisler; R.A. Knapp

2001-01-01

We used analyses based on surveys of . 1700 water bodies in a 100,000-ha area in the John Muir Wilderness (JMW) and Kings Canyon National Park (KCNP) to determine the influence of nonnative trout on the distribution and abundance of Hyla regilla in the High Sierra Nevada. At the landscape scale (JMW compared to KCNP), a negative relationship between trout and frogs in...

Overstory and understory dynamics in a ponderosa pine plantation vary with stand density in the Sierra Nevada: 40-year results

Treesearch

Jianwei Zhang; William W. Oliver; Martin W. Ritchie; Donald L. Neal

2013-01-01

We periodically measured overstory ponderosa pine (Pinus ponderosa) growth and understory cover and abundance in a long-term study on the west slope of the Sierra Nevada, California, USA. The study was established in 1969 in a 20-year-old plantation, thinned to basal areas of 9, 16, 23, 30, and 37 m2 ha-1...

Sedimentological evolution of the Cretaceous carbonate platform of Chiapas (Mexico)

NASA Astrophysics Data System (ADS)

Cros, Pierre; Michaud, François; Fourcade, Eric; Fleury, Jean-Jacques

1998-07-01

The Cretaceous epicontinental carbonate platform of Chiapas (south-east of Mexico) extends along a 200 km NW-SE narrow strip, north of the Sierra Madre basement, from Ocozocoautla to Comitan. In the western and central domain, three stratigraphic sections of the Sierra Madre Formation (late Aptian to early Senonian) display well exposed facies sequences enabling broad facies correlations about: (1) The successive transgressive-regressive stages, (2) the different subsidence rates controlling the outer to inner platform environmental evolution, (3) the conditions of tectonically controlled partial platform drowning during Campanian-Maastrichtian. Three other sections through the eastern Maastrichtian carbonate platform area record the changes from limestone to dolomite during the Angostura Maastrichtian platform stage. This evolution of thickness and facies in the occidental domain of Piedra Parada and in the central domain of Guadalupe Victoria and Julian Grajales illustrates the settlement process of the carbonate platform and the general decreasing of the thickness of the Sierra Madre Formation from west to east. The eastern platform domain (Comitan) crops out extensively and enables new correlations along a south-north transect. The Sierra Madre Formation and Angostura Formation documents continuous carbonate platform sedimentation with foraminifers, rudists and dasycladacean algae during Campanian and Maastrichtian. These sections permit palaeogeographical comparisons of depositional conditions of the Mexican margin of the Maya block.

Notes from the Field: Ebola Virus Disease Response Activities During a Mass Displacement Event After Flooding--Freetown, Sierra Leone, September-November, 2015.

PubMed

Ratto, Jeffrey; Ivy, Wade; Purfield, Anne; Bangura, James; Omoko, Anthony; Boateng, Isaac; Duffy, Nadia; Sims, George; Beamer, Bryan; Pi-Sunyer, Teresa; Kamara, Sarian; Conteh, Sulaiman; Redd, John

2016-02-26

Since the start of the Ebola virus disease (Ebola) outbreak in West Africa, Sierra Leone has reported 8,706 confirmed Ebola cases and 3,956 deaths. During September 15-16, 2015, heavy rains flooded the capital, Freetown, resulting in eight deaths, home and property destruction, and thousands of persons in need of assistance. By September 27, approximately 13,000 flood-affected persons registered for flood relief services from the government. On September 17, two stadiums in Freetown were opened to provide shelter and assistance to flood-affected residents; a total of approximately 3,000 persons stayed overnight in both stadiums (Sierra Leone Ministry of Health and Sanitation, personal communication, September 2015). On the same day the stadiums were opened to flood-affected persons, the Ministry of Health and Sanitation (MoHS) and Western Area Ebola Response Center (WAERC) staff members from CDC, the World Health Organization (WHO), and the African Union evaluated the layout, logistics, and services at both stadiums and identified an immediate need to establish Ebola response activities. The patient in the last Ebola case in the Western Area, which includes Freetown, had died 37 days earlier, on August 11; however, transmission elsewhere in Sierra Leone was ongoing, and movement of persons throughout the country was common.

Evidence for nutrient enrichment of high-elevation lakes in the Sierra Nevada, California

USGS Publications Warehouse

Sickman, James O.; Melack, John M.; Clow, David W.

2003-01-01

Long-term measurements (1983-2001) of nutrients and seston in Emerald Lake (Sierra Nevada, California) have revealed ecologically significant patterns. Nitrate, both during spring runoff and during growing seasons, declined from 1983 through 1995. Declining snowmelt nitrate was caused primarily by changes in snow regime induced by the 1987-1992 drought: years with shallow, early melting snowpacks had lower snowmelt nitrate concentrations owing to less labile N production in catchment soils and longer plant growing seasons. However, nitrate declines during growing seasons carried through the wetter years of 1993-2000 and are likely the result of increased P loading to the lake and the release of phytoplankton from P limitation. Contemporaneous with these changes was an increase in algal biomass and a shift from P limitation toward more frequent N limitation of phytoplankton abundance. Particulate carbon concentrations in the late 1990s were two- to threefold greater than in the early 1980s. These trends were reflected in a larger set of Sierra Nevada lakes sampled as part of synoptic surveys (n = 28). Between 1985 and 1999, nitrate decreased and total P increased in >70% of the lakes sampled. Our data suggest that lakes throughout the Sierra Nevada are experiencing measurable eutrophication in response to the atmospheric deposition of nutrients.

[Establishment of Quality Control System of Nucleic Acid Detection for Ebola Virus in Sierra Leone-China Friendship Biological Safety Laboratory].

PubMed

Wang, Qin; Zhang, Yong; Nie, Kai; Wang, Huanyu; Du, Haijun; Song, Jingdong; Xiao, Kang; Lei, Wenwen; Guo, Jianqiang; Wei, Hejiang; Cai, Kun; Wang, Yanhai; Wu, Jiang; Gerald, Bangura; Kamara, Idrissa Laybohr; Liang, Mifang; Wu, Guizhen; Dong, Xiaoping

2016-03-01

The quality control process throughout the Ebola virus nucleic acid detection in Sierra Leone-China Friendship Biological Safety Laboratory (SLE-CHN Biosafety Lab) was described in detail, in order to comprehensively display the scientific, rigorous, accurate and efficient practice in detection of Ebola virus of first batch detection team in SLE-CHN Biosafety Lab. Firstly, the key points of laboratory quality control system was described, including the managements and organizing, quality control documents and information management, instrument, reagents and supplies, assessment, facilities design and space allocation, laboratory maintenance and biosecurity. Secondly, the application of quality control methods in the whole process of the Ebola virus detection, including before the test, during the test and after the test, was analyzed. The excellent and professional laboratory staffs, the implementation of humanized management are the cornerstone of the success; High-level biological safety protection is the premise for effective quality control and completion of Ebola virus detection tasks. And professional logistics is prerequisite for launching the laboratory diagnosis of Ebola virus. The establishment and running of SLE-CHN Biosafety Lab has landmark significance for the friendship between Sierra Leone and China, and the lab becomes the most important base for Ebola virus laboratory testing in Sierra Leone.

GPS and InSAR Observations of Active Mountain Growth Across the Sierra Nevada/Great Basin Transition

NASA Astrophysics Data System (ADS)

Hammond, W. C.; Blewitt, G.; Li, Z.; Kreemer, C. W.; Plag, H.

2010-12-01

Topographic relief across the Sierra Nevada Mountains and Great Basin of the western United States is dominated by mountain ranges and valleys that are the product of active tectonic deformation. The contemporary rate of uplift of the Sierra Nevada via slip on range front faults and/or tilting of the Sierra Nevada/Great Valley microplate (SNGV) has been the subject of controversy. For example, geologic estimates of the age of the modern range topography vary by one order of magnitude, from 3 to 30 million years. With present elevations near 3 km, the more rapid of these implied rates is large enough to be detected by the most precise GPS measurements. We use GPS vertical and horizontal components, and InSAR time series analysis to address these long standing questions about the rates of Sierran uplift. The data are from western U.S. high precision GPS networks including the EarthScope Plate Boundary Observatory, its nucleus networks, the University of Nevada Mobile Array of GPS for Nevada Transtension, and from integrated InSAR+GPS time series analysis of ERS and ENVISAT scenes acquired between 1992 and 2010 from the GeoEarthScope and WinSAR data archives. GPS data are processed using the GIPSY OASIS II software, with ambiguities resolved, ocean tidal loading, latest GMF troposphere model and antenna calibrations applied. InSAR time series analysis results provide enhanced geographic resolution, improving our ability to locate the boundary of SNGV block-like behavior. Vertical velocities from long-running continuous stations in eastern Nevada are very similar to one another, averaging -0.1 mm/yr, with standard deviation of 0.27 mm/yr, placing an upper bound on the uncertainty in vertical rates. We find agreement between the results of InSAR time series analysis aligned to GPS and GPS line of site rates at the level of 0.35 mm/yr, placing an upper bound on the uncertainty of InSAR time series results. Because we seek to infer long-term uplift rates, applicable over millions of years, we correct the geodetic velocity field for postseismic transients from earthquakes that can cause long-wavelength distortions of the GPS velocity field. The signal of viscoelastic relaxation from historic earthquakes in Central Nevada is clearly visible in the data. We remove this transient relaxation by subtracting the predictions from a published model, although the effect on SNGV vertical motion is negligible. There is general agreement among stations on the west slope of the Sierra Nevada, near the central and southern Sierra between latitude 36° and 39°, that the rates are between 0.8 and 1.6 mm/yr upward with respect to eastern Nevada. These rates are in broad agreement with normal slip rates on the range front faults along the eastern edge of the SNGV estimated using block models constrained by horizontal GPS measurements. Thus our results agree with models that call for a Sierra Nevada uplift rate near 1 mm/yr, and a younger Sierra Nevada whose age is on the order of 3 Ma.

Regional polyphase deformation of the Eastern Sierras Pampeanas (Argentina Andean foreland): strengths and weaknesses of paleostress inversion

NASA Astrophysics Data System (ADS)

Traforti, Anna; Zampieri, Dario; Massironi, Matteo; Viola, Giulio; Alvarado, Patricia; Di Toro, Giulio

2016-04-01

The Eastern Sierras Pampeanas of central Argentina are composed of a series of basement-cored ranges, located in the Andean foreland c. 600 km east of the Andean Cordillera. Although uplift of the ranges is partly attributed to the regional Neogene evolution (Ramos et al. 2002), many questions remain as to the timing and style of deformation. In fact, the Eastern Sierras Pampeanas show compelling evidence of a long lasting brittle history (spanning the Early Carboniferous to Present time), characterised by several deformation events reflecting different tectonic regimes. Each deformation phase resulted in further strain increments accommodated by reactivation of inherited structures and rheological anisotropies (Martino 2003). In the framework of such a polyphase brittle tectonic evolution affecting highly anisotropic basement rocks, the application of paleostress inversion methods, though powerful, suffers from some shortcomings, such as the likely heterogeneous character of fault slip datasets and the possible reactivation of even highly misoriented structures, and thus requires careful analysis. The challenge is to gather sufficient fault-slip data, to develop a proper understanding of the regional evolution. This is done by the identification of internally consistent fault and fracture subsets (associated to distinct stress states on the basis of their geometric and kinematic compatibility) in order to generate a chronologically-constrained evolutionary conceptual model. Based on large fault-slip datasets collected in the Sierras de Cordoba (Eastern Sierras Pampeanas), reduced stress tensors have been generated and interpreted as part of an evolutionary model by considering the obtained results against: (i) existing K-Ar illite ages of fault gouges in the study area (Bense et al. 2013), (ii) the nature and orientation of pre-existing anisotropies and (iii) the present-day stress field due to the convergence of the Nazca and South America plates (main shortening oriented WSW-ENE). Although remarkable differences in reactivation mechanisms have been observed for the various studied lithological domains (schist, gneiss and granitic rocks), the brittle regional polyphase deformation of the Eastern Sierras Pampeanas appears to be dominated by two extensional episodes (σ3 oriented NE/ENE and WNW, respectively), which can be associated with Middle-Late Permian to Early Cretaceous tectonism, followed by a compressional paleostress (σ1 oriented ENE), which is compatible with the present day Andean convergence. Paleostress inversion techniques, despite all uncertainties involved, represent a robust approach to disentangle complex polyphase deformation histories both in term of reactivation mechanisms and strain partitioning. References: Bense, F. A., Wemmer, K., Löbens, S., & Siegesmund, S. (2013). Fault gouge analyses: K-Ar illite dating, clay mineralogy and tectonic significance-a study from the Sierras Pampeanas, Argentina. International Journal of Earth Sciences, 103, 189-218. Martino, R. D. (2003). Las fajas de deformación dúctil de las Sierras Pampeanas de Córdoba : Una reseña general. Revista de La Asociación Geológica Argentina, 58(4), 549-571. Ramos, V. A., Cristallini, E. O., & Perez, D. J. (2002). The Pampean flat-slab of the Central Andes. Journal of South American Earth Sciences, 15, 59-78.

Spatial and seasonal patterns of particulate matter less than 2.5 microns in the Sierra Nevada Mountains, California

Treesearch

Ricardo Cisneros; Don Schweizer; Haiganoush Preisler; Deborah H. Bennett; Glenn Shaw; Andrzej Bytnerowicz

2014-01-01

This paper presents particulate matter data collected in the California southern Sierra Nevada Mountains (SNM) during 2002 to 2009 from the Central Valley (elevation 91 m) into the SNM (elevation 2,598 m). Annual average concentrations of particles smaller than 2.5 µm in diameter (PM2.5) for all sites during this study ranged from 3.1 to 22.2 µg...

Fire-scar formation in Jeffrey pine - mixed conifer forests in the Sierra San Pedro Martir, Mexico

Treesearch

Scott L. Stephens; Danny L. Fry; Brandon M. Collins; Carl N. Skinner; Ernesto Franco-Vizcaino; Travis J. Freed

2010-01-01

Little is known about the probability of fire-scar formation. In this study, we examined all mixed conifer trees for fire-scar formation in a 16 ha watershed that burned as part of a 2003 wildfire in Sierra San Pedro Ma´rtir National Park (SSPM), Mexico. In addition, we examine the probability of fire-scar formation in relation to the previous fire interval in forests...

Effects of Selective Logging on Birds in the Sierra de Coalcoman, Sierra Madre del Sur, Michoacan, Western Mexico

Treesearch

Jose Fernando Villaseñor; Neyra Sosa; Laura Villaseñor

2005-01-01

In order to determine the effects of selective logging on pine-oak forest?s bird communities in central-western Mexico, we gathered information through 10-min point counts in plots without wood extraction and sites logged at different times in the past (1, 4, and 8 years). We did not find evidences to argue for effects of logging on bird communities; the study plots...

Early Pleistocene(?) pollen spectra from near Lake Tahoe, California

USGS Publications Warehouse

Adam, David P.

1973-01-01

Fossil pollen was recovered at Tahoe City, Calif., from beneath a 1.9-m.y.-old volcanic flow. Pollen counts of four fossil samples are compared with soil-surface pollen samples from the Sierra Nevada. The presence of Picea (spruce) pollen in the fossil samples suggests that summer drought conditions in the central Sierra Nevada were less severe prior to 1.9 m.y. ago than they are now.

Critical Loads of Acid Deposition for Wilderness Lakes in the Sierra Nevada (California) Estimated by the Steady-State Water Chemistry Model

Treesearch

Glenn D. Shaw; Ricardo Cisneros; Donald Schweizer; James O. Sickman; Mark E. Fenn

2014-01-01

Major ion chemistry (2000-2009) from 208 lakes (342 sample dates and 600 samples) in class I and II wilderness areas of the Sierra Nevada was used in the Steady-State Water Chemistry (SSWC) model to estimate critical loads for acid deposition and investigate the current vulnerability of high elevation lakes to acid deposition. The majority of the lakes were dilute (...

Rice Production. A Training Manual and Field Guide to Small-Farm Irrigated Rice Production. Appropriate Technologies for Development. Reprint No. R-40.

ERIC Educational Resources Information Center

Morris, Michael L., Ed.

This manual presents a simple, step-by-step description of irrigated rice production in Sierra Leone. It is geared specifically to the role and needs of Peace Corps volunteers who, since the mid-1970s, have worked as agricultural extension agents in the Sierra Leone Ministry of Agriculture and Forestry. The manual is designed to serve both as a…

Natural range of variation for yellow pine and mixed-conifer forests in the Sierra Nevada, southern Cascades, and Modoc and Inyo National Forests, California, USA

Treesearch

Hugh D. Safford; Jens T. Stevens

2017-01-01

Yellow pine and mixed-conifer (YPMC) forests are the predominant montane forest type in the Sierra Nevada, southern Cascade Range, and neighboring forested areas on the Modoc and Inyo National Forests (the "assessment area"). YPMC forests occur above the oak woodland belt and below red fir forests, and are dominated by the yellow pines (ponderosa pine [

Landscape fuel reduction, forest fire, and biophysical linkages to local habitat use and local persistence of fishers (Pekania pennanti) in Sierra Nevada mixed-conifer forests

Treesearch

R.A. Sweitzer; B.J. Furnas; R.H. Barrett; Kathryn Purcell; Craig Thompson

2016-01-01

Fire suppression and logging have contributed to major changes in California’s Sierra Nevada forests. Strategically placed landscape treatments (SPLATS) are being used to reduce density of trees, shrubs, and surface fuels to limit wildfire intensity and spread, but may negatively impact fishers (Pekania pennanti). We used camera traps to survey for...

75 FR 55961 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-15

.../1/10 LOC RWY 8, AMDT 5A. 21-Oct-10 AZ FORT HUACHUCA/ SIERRA VISTA MUNI- 0/5486 8/30/10 TAKEOFF MINIMUMS AND OBSTACLE DP, AMDT 2. SIERRA VISTA. LIBBY AAF. 21-Oct-10 LA LAKE CHARLES..... LAKE CHARLES RGNL... LOC/DME RWY 14, AMDT 8. 21-Oct-10 LA SLIDELL SLIDELL 0/7403 8/30/10 NDB RWY 36, ORIG-D. 21-Oct-10 FL...

The source provenance of an obsidian Eden point from Sierra County, New Mexico

DOE PAGES

Dolan, Sean Gregory; Berryman, Judy; Shackley, M. Steven

2016-01-02

Eden projectile points associated with the Cody complex are underrepresented in the late Paleoindian record of the American Southwest. EDXRF analysis of an obsidian Eden point from a site in Sierra County, New Mexico demonstrates this artifact is from the Cerro del Medio (Valles Rhyolite) source in the Jemez Mountains. Lastly, we contextualize our results by examining variability in obsidian procurement practices beyond the Cody heartland in southcentral New Mexico.

Application Modernization at LLNL and the Sierra Center of Excellence

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neely, J. Robert; de Supinski, Bronis R.

We repport that in 2014, Lawrence Livermore National Laboratory began acquisition of Sierra, a pre-exascale system from IBM and Nvidia. It marks a significant shift in direction for LLNL by introducing the concept of heterogeneous computing via GPUs. LLNL’s mission requires application teams to prepare for this paradigm shift. Thus, the Sierra procurement required a proposed Center of Excellence that would align the expertise of the chosen vendors with laboratory personnel that represent the application developers, system software, and tool providers in a concentrated effort to prepare the laboratory’s codes in advance of the system transitioning to production in 2018.more » Finally, this article presents LLNL’s overall application strategy, with a focus on how LLNL is collaborating with IBM and Nvidia to ensure a successful transition of its mission-oriented applications into the exascale era.« less

SIERRA/Aero Theory Manual Version 4.46.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sierra Thermal/Fluid Team

2017-09-01

SIERRA/Aero is a two and three dimensional, node-centered, edge-based finite volume code that approximates the compressible Navier-Stokes equations on unstructured meshes. It is applicable to inviscid and high Reynolds number laminar and turbulent flows. Currently, two classes of turbulence models are provided: Reynolds Averaged Navier-Stokes (RANS) and hybrid methods such as Detached Eddy Simulation (DES). Large Eddy Simulation (LES) models are currently under development. The gas may be modeled either as ideal, or as a non-equilibrium, chemically reacting mixture of ideal gases. This document describes the mathematical models contained in the code, as well as certain implementation details. First, themore » governing equations are presented, followed by a description of the spatial discretization. Next, the time discretization is described, and finally the boundary conditions. Throughout the document, SIERRA/ Aero is referred to simply as Aero for brevity.« less

SIERRA/Aero Theory Manual Version 4.44

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sierra Thermal /Fluid Team

2017-04-01

SIERRA/Aero is a two and three dimensional, node-centered, edge-based finite volume code that approximates the compressible Navier-Stokes equations on unstructured meshes. It is applicable to inviscid and high Reynolds number laminar and turbulent flows. Currently, two classes of turbulence models are provided: Reynolds Averaged Navier-Stokes (RANS) and hybrid methods such as Detached Eddy Simulation (DES). Large Eddy Simulation (LES) models are currently under development. The gas may be modeled either as ideal, or as a non-equilibrium, chemically reacting mixture of ideal gases. This document describes the mathematical models contained in the code, as well as certain implementation details. First, themore » governing equations are presented, followed by a description of the spatial discretization. Next, the time discretization is described, and finally the boundary conditions. Throughout the document, SIERRA/ Aero is referred to simply as Aero for brevity.« less

Climate controls on forest productivity along the climate gradient of the western Sierra Nevada

NASA Astrophysics Data System (ADS)

Kelly, A. E.; Goulden, M. L.

2010-12-01

The broad climate gradient of the slopes of the western Sierra Nevada mountains supports ecosystems spanning extremes of productivity, biomass, and function. We are using this natural environmental gradient to understand how climate controls NPP, aboveground biomass, species' range limits, and phenology. Our experimental approach combines eddy covariance, sap flow, dendrometer, and litterfall measurements in combination with soil and hydrological data from the Southern Sierra Critical Zone Observatory (SSCZO). We have found that above about 2500 m, forest productivity is limited by winter cold, while below 1200 m, productivity is likely limited by summer drought. The sweet spot between these elevations has a nearly year-long growing season despite a snowpack that persists for as long as six months. Our results show that small differences in temperature can markedly alter the water balance and productivity of mixed conifer forests.

KSC-2011-8116

NASA Image and Video Library

2011-12-01

CAPE CANAVERAL, Fla. -- This is an artist's conception of the Dream Chaser spacecraft under development by Sierra Nevada of Centennial, Colo., for NASA's Commercial Crew Program (CCP). In 2011, NASA selected Sierra Nevada during Commercial Crew Development Round 2 (CCDev2) activities to mature the design and development of a crew transportation system with the overall goal of accelerating a United States-led capability to the International Space Station. The goal of CCP is to drive down the cost of space travel as well as open up space to more people than ever before by balancing industry’s own innovative capabilities with NASA's 50 years of human spaceflight experience. Six other aerospace companies also are maturing launch vehicle and spacecraft designs under CCDev2, including Alliant Techsystems Inc. (ATK), The Boeing Co., Excalibur Almaz Inc., Blue Origin, Space Exploration Technologies (SpaceX), and United Launch Alliance (ULA). For more information, visit www.nasa.gov/commercialcrew. Image credit: Sierra Nevada Corp.

Sequence Variability and Geographic Distribution of Lassa Virus, Sierra Leone

PubMed Central

Stockelman, Michael G.; Moses, Lina M.; Park, Matthew; Stenger, David A.; Ansumana, Rashid; Bausch, Daniel G.; Lin, Baochuan

2015-01-01

Lassa virus (LASV) is endemic to parts of West Africa and causes highly fatal hemorrhagic fever. The multimammate rat (Mastomys natalensis) is the only known reservoir of LASV. Most human infections result from zoonotic transmission. The very diverse LASV genome has 4 major lineages associated with different geographic locations. We used reverse transcription PCR and resequencing microarrays to detect LASV in 41 of 214 samples from rodents captured at 8 locations in Sierra Leone. Phylogenetic analysis of partial sequences of nucleoprotein (NP), glycoprotein precursor (GPC), and polymerase (L) genes showed 5 separate clades within lineage IV of LASV in this country. The sequence diversity was higher than previously observed; mean diversity was 7.01% for nucleoprotein gene at the nucleotide level. These results may have major implications for designing diagnostic tests and therapeutic agents for LASV infections in Sierra Leone. PMID:25811712

Failure of Sierra White granite under general states of stress

NASA Astrophysics Data System (ADS)

Ingraham, M. D.; Dewers, T. A.; Lee, M.; Holdman, O.; Cheung, C.; Haimson, B. C.

2017-12-01

The effect of the intermediate principal stress on the failure of Sierra White granite was investigated by performing tests under true triaxial states of stress. Tests were performed under constant Lode angle conditions with Lode angles ranging from 0 to 30°, pure shear to axisymmetric compression. Results show that the failure of Sierra White granite is heavily dependent on the intermediate principal stress which became more dramatic as the mean stress increased. An analysis of the shear bands formed at failure was performed using an associated flow rule and the Rudnicki and Rice (1975) localization criteria. The localization analysis showed excellent agreement with experimental results. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.

Application Modernization at LLNL and the Sierra Center of Excellence

DOE PAGES

Neely, J. Robert; de Supinski, Bronis R.

2017-09-01

We repport that in 2014, Lawrence Livermore National Laboratory began acquisition of Sierra, a pre-exascale system from IBM and Nvidia. It marks a significant shift in direction for LLNL by introducing the concept of heterogeneous computing via GPUs. LLNL’s mission requires application teams to prepare for this paradigm shift. Thus, the Sierra procurement required a proposed Center of Excellence that would align the expertise of the chosen vendors with laboratory personnel that represent the application developers, system software, and tool providers in a concentrated effort to prepare the laboratory’s codes in advance of the system transitioning to production in 2018.more » Finally, this article presents LLNL’s overall application strategy, with a focus on how LLNL is collaborating with IBM and Nvidia to ensure a successful transition of its mission-oriented applications into the exascale era.« less

A new species of Rhadinella (Serpentes: Colubridae) from the Sierra Madre del Sur of Guerrero, Mexico.

PubMed

Campillo, Gustavo; Dávila-Galavíz, Luis Fernando; Flores-Villela, Oscar; Campbell, Jonathan A

2016-04-12

We describe a new species of Rhadinella from the Sierra Madre del Sur of Guerrero, Mexico, a region where the genus was previously unknown. This diminutive species is a member of a group of snakes previously allocated in the Rhadinaea godmani group, and more recently transferred to the genus Rhadinella. These snakes may have conspicuous dark longitudinal striping on a pale brown to orange background or may have dark brown to blackish dorsal ground coloration, which mostly or completely obfuscates a pattern of longitudinal striping. The new species is mostly dark with barely discernible slightly paler or darker striping (depending on how striping is interpreted). The closest relative of the new species, on the basis of morphological similarities and biogeography, appears to be Rhadinella donaji which occurs to the east in the Sierra Madre del Sur of Oaxaca about 275 km from the type-locality of the new species.

Diversification in the South American Pampas: the genetic and morphological variation of the widespread Petunia axillaris complex (Solanaceae).

PubMed

Turchetto, Caroline; Fagundes, Nelson J R; Segatto, Ana L A; Kuhlemeier, Cris; Solís Neffa, Viviana G; Speranza, Pablo R; Bonatto, Sandro L; Freitas, Loreta B

2014-02-01

Understanding the spatiotemporal distribution of genetic variation and the ways in which this distribution is connected to the ecological context of natural populations is fundamental for understanding the nature and mode of intraspecific and, ultimately, interspecific differentiation. The Petunia axillaris complex is endemic to the grasslands of southern South America and includes three subspecies: P. a. axillaris, P. a. parodii and P. a. subandina. These subspecies are traditionally delimited based on both geography and floral morphology, although the latter is highly variable. Here, we determined the patterns of genetic (nuclear and cpDNA), morphological and ecological (bioclimatic) variation of a large number of P. axillaris populations and found that they are mostly coincident with subspecies delimitation. The nuclear data suggest that the subspecies are likely independent evolutionary units, and their morphological differences may be associated with local adaptations to diverse climatic and/or edaphic conditions and population isolation. The demographic dynamics over time estimated by skyline plot analyses showed different patterns for each subspecies in the last 100 000 years, which is compatible with a divergence time between 35 000 and 107 000 years ago between P. a. axillaris and P. a. parodii, as estimated with the IMa program. Coalescent simulation tests using Approximate Bayesian Computation do not support previous suggestions of extensive gene flow between P. a. axillaris and P. a. parodii in their contact zone. © 2013 John Wiley & Sons Ltd.

A Paleomagnetic Investigation of Large-Scale Vertical Axis Rotations in Coastal Sonora: Evidence for Transtensional Proto-Gulf Deformation

NASA Astrophysics Data System (ADS)

Herman, S. W.; Gans, P. B.

2006-12-01

A paleomagnetic investigation into possible vertical axis rotations has been conducted in the Sierra el Aguaje and Sierra Tinajas del Carmen, Sonora, Mexico, in order assess proposed styles for oblique continental rifting in the Gulf of California. Two styles of rifting have been proposed; (1) strain partitioning (Stock and Hodges, 89), and (2) transtension (Gans, 97), for the Proto-Gulf period of the Gulf of California. The presence of large- scale vertical axis rotations would lend weight to the argument for transtension. The Sierra el Aguaje and Sierra Tinajas del Carmen are located in southwestern coastal Sonora, Mexico. The ranges represent the eastern-rifted margin of the central Gulf of California. This is one of the few areas of that margin which is entirely above water, with new ocean crust of the Guaymas basin lying immediately offshore of the western edge of the ranges. The ranges are composed of volcanic units and their corresponding volcaniclastic units that are the result of persistent magmatic activity between 20 and 8.8 Ma, including three packages of basalt and andesite that make excellent paleomagnetic recorders. Based on cross cutting relations and geochronologic data for pre-, syn-, and post-tectonic volcanic units, most of the faulting and tilting in the Sierra El Aguaje and Sierra Tinajas del Carmen is bracketed between 11.9 and 9.0 Ma, thus falling entirely within Proto-Gulf time. Existing field relations suggest the presence of large (>45°) vertical axis rotations in this region. This evidence includes: a) abrupt changes in the strike of tilted strata in different parts of the range b) ubiquitous NE-SW striking faults with left lateral-normal oblique slip, that terminate against major NW-trending right lateral faults, and c) obliquity between the general strike of tilted strata and the strike of faults. The results of the paleomagnetic investigation are consistent with the field evidence and show large clockwise rotations between ~30° and ~100° with no discernable translation. Such large-scale rotations lend credence to the theory that the area inboard of Baja California was experiencing transtension during the Proto-Gulf period, rather than the pure extension that would have been the result of strain partitioning.

Moho Structure of the Central Sierra Nevada From an EarthScope Flex Array Deployment

NASA Astrophysics Data System (ADS)

Burdick, S.; Zandt, G.; Gilbert, H.; Jones, C.; Owens, T.

2005-12-01

Findings from the southern Sierra Nevada (south of 37 degrees north) show that the crustal thickness in the southern Sierra Nevada range does not obey an Airy isostasy model. Receiver function data show that the crustal thickness generally increases across the range from the high eastern peaks to the low western foothills, and the Moho discontinuity disappears beneath parts of the western foothills. This disappearance of the Moho has been attributed to the entrainment of the crust into the mantle by the convective removal of the southern batholithic root during the past 3-4 M yrs (Zandt et al., Nature, 2004). Other possible causes of Moho disappearance include a very gradational, or even inverted, impedance contrast due to lower crustal or upper mantle wavespeed anomalies. During the summer of 2005, the Sierra Nevada Earthscope Project (SNEP) has deployed an Earthscope flex array of over forty broadband seismometers with 25 km spacing, designed to constrain lithospheric structure of the central Sierra Nevada between the latitudes of approximately 37 to 38 degrees north. We will report on a receiver function study to better define the boundaries of the Moho "hole" to the north. Initial receiver functions from the first stations deployed mainly on the western and eastern flanks of the range show a northward continuation of both the "hole" under the western margin and a high amplitude Moho under the eastern flank of the range. This new observation suggests either the Moho disappearance is unrelated to the convective removal of the southern root or that root removal has affected the Sierra Nevada significantly farther north than suggested by presently available volcanic and xenolith evidence. Receiver functions collected from SNEP data will be processed into move-out corrected depth stacks in order to present a more complete map of Moho depth and amplitude beneath the region. To quantify the range of impedance contrasts capable of producing the observed variability in Moho amplitude, observed receiver function arrivals will be compared to synthetic examples calculated for a range of lower crustal and upper mantle wavespeeds. In conjunction with other studies these results should lead to a better understanding of the scale and processes associated with a young lithospheric foundering event.

The burden of musculoskeletal disease in Sierra Leone.

PubMed

Elliott, Iain S; Groen, Reinou S; Kamara, Thaim B; Ertl, Allison; Cassidy, Laura D; Kushner, Adam L; Gosselin, Richard A

2015-01-01

Musculoskeletal disease is a major cause of disability in the global burden of disease, yet data regarding the magnitude of this burden in developing countries are lacking. The Surgeons OverSeas Assessment of Surgical Need (SOSAS) survey was designed to measure the incidence and prevalence of surgically treatable conditions, including musculoskeletal conditions, in patients in low- and middle-income countries, and was administered in the West African nation of Sierra Leone in 2012. We attempted to quantify the burden of potentially treatable musculoskeletal conditions in patients in Sierra Leone. A cross-sectional two-stage cluster-based survey was performed in Sierra Leone using the SOSAS. Two individuals from each randomly selected household underwent a verbal head to toe examination. The musculoskeletal-related questions from the SOSAS survey in Sierra Leone were analyzed to determine the prevalence of musculoskeletal problems in the study population. Prevalence is reported as the number of respondents with a musculoskeletal problem now and number of respondents with a musculoskeletal problem during the past year. Respondents had "no need" for care, they "received care", or they faced a barrier that prevented them from receiving care. One thousand eight hundred seventy-five households were targeted, with 1843 undergoing the survey, which yielded 3645 individual respondents. Of the individual respondents, 462 (n=3645; 12.6% of total; 95% CI, 12%-13%) had a traumatic musculoskeletal problem during the past year, and 236 (n=3645; 6% of total; 95% CI, 5%-7%) respondents had a musculoskeletal problem of nontraumatic etiology. Of respondents with either a traumatic or nontraumatic musculoskeletal problem, 359 (n=562; 63.9% of total; 95% CI, 59.5-68.3%) needed care but were unable to receive it with the major barrier reported as financial. Resource allocation decisions in global health are made based on burden of disease data in low- and middle-income countries. The data provided here for Sierra Leone may offer some generalizable insight into the scope of the burden of musculoskeletal disease for low- and middle-income countries, especially in Sub-Saharan Africa, and provide concrete evidence that musculoskeletal health should be included in the global health discussion. However, there may be important differences across countries in this region, and further study to elucidate these differences seems critical given the large burden of disease and the limited resources available in these regions to manage it.

Groundwater quality in the Central Sierra Nevada, California

USGS Publications Warehouse

Fram, Miranda S.; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. Two small watersheds of the Fresno and San Joaquin Rivers in the Central Sierra Nevada constitute one of the study units being evaluated.

Groundwater quality in the Southern Sierra Nevada, California

USGS Publications Warehouse

Fram, Miranda S.; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The Tehachapi-Cummings Valley and Kern River Valley basins and surrounding watersheds in the Southern Sierra Nevada constitute one of the study units being evaluated.

Distribution and Climatic Relationships of the American Pika (Ochotona princeps) in the Sierra Nevada and Western Great Basin, U.S.A.; Periglacial Landforms as Refugia in Warming Climates

Treesearch

Constance I. Millar; Robert D. Westfall

2010-01-01

We used a rapid assessment to survey American pika (Ochotona princeps) populations and documented 420 pika site occurrences in southwestern U.S.A. These included 329 sites from the Sierra Nevada (SN), California; 67 from six southwestern Great Basin (swGB) ranges, California and Nevada; 16 from three central Great Basin ranges, Nevada; and 8 from...

Interpretation of snowcover from satellite imagery for use in water supply forecasts in the Sierra Nevada

NASA Technical Reports Server (NTRS)

Brown, A. J.; Hannaford, J. F.

1975-01-01

The California ASVT test area is composed of two study areas; one in Northern California covering the Upper Sacramento and Feather River Basins, and the other covering the Southern Sierra Basins of the San Joaquin, Kings, Kaweah, Tule, and Kern Rivers. Experiences of reducing snowcover from satellite imagery; the accuracy of present water supply forecast schemes; and the potential advantages of introducing snowcover into the forecast procedures are described.

Sierra Madre Oriental in Coahuila, Mexico

NASA Technical Reports Server (NTRS)

2002-01-01

This desolate landscape is part of the Sierra Madre Oriental mountain range, on the border between the Coahuila and Nuevo Leon provinces of Mexico. This image was acquired by Landsat 7's Enhanced Thematic Mapper plus (ETM+) sensor on November 28, 1999. This is a false-color composite image made using shortwave infrared, infrared, and green wavelengths. The image has also been sharpened using the sensor's panchromatic band. Image provided by the USGS EROS Data Center Satellite Systems Branch