Agricultural conservation planning framework: 2. Classification of riparian buffer design types with application to assess and map stream corridors.

PubMed

Tomer, M D; Boomer, K M B; Porter, S A; Gelder, B K; James, D E; McLellan, E

2015-05-01

A watershed's riparian corridor presents opportunities to stabilize streambanks, intercept runoff, and influence shallow groundwater with riparian buffers. This paper presents a system to classify these riparian opportunities and apply them toward riparian management planning in hydrologic unit code 12 watersheds. In two headwater watersheds from each of three landform regions found in Iowa and Illinois, high-resolution (3-m grid) digital elevation models were analyzed to identify spatial distributions of surface runoff contributions and zones with shallow water tables (SWTs) (within 1.5 m of the channel elevation) along the riparian corridors. Results were tabulated, and a cross classification was applied. Classes of buffers include those primarily placed to (i) trap runoff and sediment, (ii) influence shallow groundwater, (iii) address both runoff and shallow groundwater, and (iv) maintain/improve stream bank stability. Riparian buffers occupying about 2.5% of these six watersheds could effectively intercept runoff contributions from 81 to 94% of the watersheds' contributing areas. However, extents of riparian zones where a narrow buffer (<10 m wide) would adequately intercept runoff but where >25 m width of buffer vegetation could root to a SWT varied according to landform region ( < 0.10). Yet, these wide-SWT riparian zones were widespread and occupied 23 to 53% of the lengths of stream banks among the six watersheds. The wide-SWT setting provides opportunities to reduce dissolved nutrients (particularly NO-N) carried via groundwater. This riparian classification and mapping system is part of a ArcGIS toolbox and could provide a consistent basis to identify riparian management opportunities in Midwestern headwater catchments wherever high-resolution elevation data are available. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Acidic Deposition along the Appalachian Trail Corridor and its Effects on Acid-Sensitive Terrestrial and Aquatic Resources

NASA Astrophysics Data System (ADS)

Lawrence, G. B.; Sullivan, T. J.; Burns, D. A.; Bailey, S. W.; Cosby, B. J., Jr.; Dovciak, M.; Ewing, H. A.; McDonnell, T. C.; Riemann, R.; Quant, J.; Rice, K. C.; Siemion, J.; Weathers, K. C.

2015-12-01

The Appalachian National Scenic Trail (AT) spans 3,500 km from Georgia to Maine. Over its length, the trail passes through a corridor with wide variations in climate, bedrock type, soils, and stream water quality. These factors create a diverse range of ecosystems. The health of these ecosystems is a cause for concern because the AT passes through the heavily populated eastern U.S. with its many sources of sulfur (S) and nitrogen (N) emissions that produce acidic deposition. To address concerns about the health of the AT, a study was designed to evaluate the condition and sensitivity of the AT corridor with respect to acidic deposition. Collections of stream water (265 sites), soil (60 sites), tree cores (15 sites) and atmospheric deposition samples (4 sites) were made along with understory and overstory vegetation measurements (30 sites) over the full trail length within a 40 km-wide corridor. Existing data on atmospheric deposition, geology, vegetation, stream chemistry, and soil chemistry were also used in the analysis. Mean acid-neutralizing capacity (ANC) was lowest in the streams in the North section, intermediate in the Central section and highest the South section, despite the South having the highest acid rain levels. At least 40% of the study streams exhibited pH and/or Ali measurements that indicated potential harm to biota. Approximately 70% of the soil sites had values of base saturation under 20%, the threshold below which acidic deposition can mobilize inorganic aluminum (Ali), the form harmful to terrestrial and aquatic life. Compositional similarity of understory and canopy species was positively correlated with acidic deposition, suggesting that during past decades, species poorly adapted to acidic deposition were replaced with tolerant species. Target loads modeling indicated that exceedance of sulfur target loads to achieve stream ANC = 50 μeq/L by the year 2100occurred throughout the trail corridor.

A landscape perspective of the stream corridor invasion and habitat characteristics of an exotic (Dioscorea oppositifolia) in a pristine watershed in Illinois

USGS Publications Warehouse

Thomas, J.R.; Middleton, B.; Gibson, D.J.

2006-01-01

The spatial distribution of exotics across riparian landscapes is not uniform, and research elaborating the environmental constraints and dispersal behavior that underlie these patterns of distribution is warranted. This study examined the spatial distribution, growth patterns, and habitat constraints of populations of the invasive Dioscorea oppositifolia in a forested stream corridor of a tributary of Drury Creek in Giant City State Park, IL. The distribution of D. oppositifolia was determined at the watershed scale mainly by floodplain structure and connectivity. Populations of D. oppositifolia were confined to the floodplain, with overbank flooding from the stream. Dioscorea oppositifolia probably originates in disturbed areas upstream of natural corridors, and subsequently, the species disperses downstream into pristine canyons or ravines via bulbils dispersing in the water. In Giant City State Park, populations of D. oppositifolia were distributed on the floodplain across broad gradients of soil texture, light, slope, and potential radiation. The study also examined the longevity of bulbils in various micro-environments to illuminate strategies for the management of the species in invaded watersheds. After 1 year, the highest percentages of bulbils were viable under leaves, and much lower percentages were viable over leaves, in soil, and in the creek (76.0??6.8, 21.2??9.6, 21.6??3.6, and 5.2??5.2%), respectively. This study suggests that management procedures that reduce leaf litter on the forest floor (e.g., prescribed burning) could reduce the number of bulbils of D. oppositifolia stored in the watershed. ?? Springer 2006.

Terrain-based Predictive Modeling of a Functional Riparian Corridor in a Coastal Northern California Watershed

NASA Astrophysics Data System (ADS)

Robinson, T.; Davis, J. D.

2016-12-01

Riparian corridors and their associated geomorphic landforms (e.g., channels, floodplains, and terraces) and vegetation communities (e.g., forests and wetlands) have been significantly degraded in California, prompting an expansion of efforts to delineate riparian corridors and identify priorities for conservation via deed restrictions and easements. Current techniques to delineate riparian corridors for these purposes include fixed-width buffers based on stream centerlines and digitization of woody vegetation from aerial photos. Although efficient, these delineation methods do not accurately capture the extent of ecologically functional riparian corridors and result in riparian habitat being excluded from conservation efforts while non-riparian is included. From a physical perspective, ecologically functional riparian corridors have widths that vary with topography and ample space for dynamic fluvial geomorphic processes that create and maintain river morphology and vegetation and sustain ecological interactions that extend from the stream channel laterally into upland ecosystems and up- and downstream ecosystems in longitudinal directions. New terrain-based spatial analysis techniques and high-resolution digital terrain data show promise in delineating ecologically functional riparian corridors. In this study, we compare the efficacy of three terrain-based predictors of riparian corridors that have emerged in the literature—elevation above channel, flow accumulation, and distance from channel. The results of each terrain predictor are compared with field-based indicators of the riparian corridor of an alluvial reach of Mark West Creek in Sonoma County, California (a mediterranean climate). Indicators include soil type, fluvial geomorphic landforms, and vegetation. A one-meter digital terrain model from LiDAR (Light Detection and Ranging) supplied by a NASA ROSES grant is used as the base terrain data for spatial analysis. We discuss in detail the use of

Connection between the two branches of the quantum two-stream instability across the k space

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

Bret, A.; Haas, F.

2010-05-15

The stability of two quantum counterstreaming electron beams is investigated within the quantum plasma fluid equations for arbitrarily oriented wave vectors k. The analysis reveals that the two quantum two-stream unstable branches are indeed connected by a continuum of unstable modes with oblique wave vectors. Using the longitudinal approximation, the stability domain for any k is analytically explained, together with the growth rate.

Mapping landscape corridors

Treesearch

Peter Vogt; Kurt H. Riitters; Marcin Iwanowski; Christine Estreguil; Jacek Kozak; Pierre Soille

2007-01-01

Corridors are important geographic features for biological conservation and biodiversity assessment. The identification and mapping of corridors is usually based on visual interpretations of movement patterns (functional corridors) or habitat maps (structural corridors). We present a method for automated corridor mapping with morphological image processing, and...

Multi-scale interactions affecting transport, storage, and processing of solutes and sediments in stream corridors (Invited)

NASA Astrophysics Data System (ADS)

Harvey, J. W.; Packman, A. I.

2010-12-01

Surface water and groundwater flow interact with the channel geomorphology and sediments in ways that determine how material is transported, stored, and transformed in stream corridors. Solute and sediment transport affect important ecological processes such as carbon and nutrient dynamics and stream metabolism, processes that are fundamental to stream health and function. Many individual mechanisms of transport and storage of solute and sediment have been studied, including surface water exchange between the main channel and side pools, hyporheic flow through shallow and deep subsurface flow paths, and sediment transport during both baseflow and floods. A significant challenge arises from non-linear and scale-dependent transport resulting from natural, fractal fluvial topography and associated broad, multi-scale hydrologic interactions. Connections between processes and linkages across scales are not well understood, imposing significant limitations on system predictability. The whole-stream tracer experimental approach is popular because of the spatial averaging of heterogeneous processes; however the tracer results, implemented alone and analyzed using typical models, cannot usually predict transport beyond the very specific conditions of the experiment. Furthermore, the results of whole stream tracer experiments tend to be biased due to unavoidable limitations associated with sampling frequency, measurement sensitivity, and experiment duration. We recommend that whole-stream tracer additions be augmented with hydraulic and topographic measurements and also with additional tracer measurements made directly in storage zones. We present examples of measurements that encompass interactions across spatial and temporal scales and models that are transferable to a wide range of flow and geomorphic conditions. These results show how the competitive effects between the different forces driving hyporheic flow, operating at different spatial scales, creates a situation

Long-Term Data Reveal Patterns and Controls on Stream Water Chemistry in a Forested Stream: Walker Branch, Tennessee

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

Lutz, Brian D; Mulholland, Patrick J; Bernhardt, Emily

2012-01-01

We present 20 years of weekly stream water chemistry, hydrology, and climate data for the Walker Branch watershed in eastern Tennessee, USA. Since 1989, the watershed has experienced a similar to 1.08 degrees C increase in mean annual temperature, a similar to 20% decline in precipitation, and a similar to 30% increase in forest evapotranspiration rates. As a result, stream runoff has declined by similar to 34%. We evaluate long-term trends in stream water concentrations and fluxes for nine solutes and use wet deposition data to calculate approximate watershed input-output budgets. Dissolved constituents were classified as geochemical solutes (Ca2+, Mg2+,more » and SO42-) or nutrients (NH4+, NO3-, soluble reactive phosphorus [SRP], total soluble nitrogen [TSN], total soluble phosphorus [TSP], and dissolved organic carbon [DOC]). Geochemical solutes are predominantly controlled by discharge, and the long-term changes in catchment hydrology have led to significant trends in the concentrations and fluxes of these solutes. Further, the trends in geochemical solute concentrations indicate shifting soil flowpath contributions to streamflow generation through time, with deep groundwater having a greater proportional contribution in recent years. Despite dramatic changes in watershed runoff, there were no trends in inorganic nutrient concentrations (NH4+, NO3-, and SRP). While most nutrients entering the watershed are retained, stream fluxes of nutrient solutes have declined significantly as a result of decreasing runoff. Nutrient concentrations in the stream exhibit large seasonality controlled by in-stream biological uptake. Stream benthic communities are sensitive to hydrologic disturbance, and changes in the frequency or intensity of storm events through time can affect nutrient fluxes. Stream NO3- concentrations are also sensitive to drought, with concentrations decreasing (increasing) if conditions during the three years prior to the time of sampling were drier

Hydrologic and hydraulic analyses at Akin Branch and Cayce Valley Branch, Columbia, Tennessee

USGS Publications Warehouse

Outlaw, George S.

1993-01-01

The U.S. Geological Survey, in cooperation with the City of Columbia, Tennessee, conducted hydrologic and hydraulic analyses at Akin Branch and Cayce Valley Branch in the Little Bigby Creek watershed, Columbia, Tennessee, from 1990 through 1991. Results of the analyses can be used by city planners in the development of plans to replace several deteriorating and inadequate drainage structures. Akin Branch and Cayce Valley Branch drain small watersheds of 1.69 and 1.04 square miles, respectively. Flood discharges for 5-, lo-, and 25-year recurrence-interval storm events were calculated at the stream mouths using flood-frequency relations developed for use at small urban streams in Tennessee. For each stream, flood discharges at locations upstream from the mouth were calculated by subdividing the watershed and assigning a percentage of the discharge at the mouth, based on drainage area, to each subarea. Flood profiles for the selected recurrence-interval flood discharges were simulated for Akin Branch and Cayce Valley Branch for existing conditions and conditions that might exist if drainage improvements such as larger culverts and bridges and channel improvements are constructed. The results of the simulations were used to predict changes in flood elevations that might result from such drainage improvements. Analyses indicate that reductions in existing flood elevations of as much as 2.1 feet for the 5-year flood at some sites on Akin Branch and as much as 3.8 feet for the 5-year flood at some sites on Cayce Valley Branch might be expected with the drainage improvements.

Geomorphology and till architecture of terrestrial palaeo-ice streams of the southwest Laurentide Ice Sheet: A borehole stratigraphic approach

NASA Astrophysics Data System (ADS)

Norris, Sophie L.; Evans, David J. A.; Cofaigh, Colm Ó.

2018-04-01

A multidimensional study, utilising geomorphological mapping and the analysis of regional borehole stratigraphy, is employed to elucidate the regional till architecture of terrestrial palaeo-ice streams relating to the Late Wisconsinan southwest Laurentide Ice Sheet. Detailed mapping over a 57,400 km2 area of southwestern Saskatchewan confirms previous reconstructions of a former southerly flowing ice stream, demarcated by a 800 km long corridor of megaflutes and mega-scale glacial lineations (Ice Stream 1) and cross cut by three, formerly southeast flowing ice streams (Ice Streams 2A, B and C). Analysis of the lithologic and geophysical characteristics of 197 borehole samples within these corridors reveals 17 stratigraphic units comprising multiple tills and associated stratified sediments overlying preglacial deposits, the till thicknesses varying with both topography and distance down corridor. Reconciling this regional till architecture with the surficial geomorphology reveals that surficial units are spatially consistent with a dynamic switch in flow direction, recorded by the cross cutting corridors of Ice Streams 1, 2A, B and C. The general thickening of tills towards lobate ice stream margins is consistent with subglacial deformation theory and variations in this pattern on a more localised scale are attributed to influences of subglacial topography including thickening at buried valley margins, thinning over uplands and thickening in overridden ice-marginal landforms.

Corridor Planning And Feasibility Analysis Corridor, Master Plan

DOT National Transportation Integrated Search

1996-04-01

THE I-70 RURAL IVHS CORRIDOR MASTER PLAN IS THE GUIDANCE DOCUMENT FOR DEPLOYMENT OF THE INTELLIGENT TRANSPORTATION SYSTEM (ITS) FOR THE INTERSTATE-70 CORRIDOR FROM DENVER TO GLENWOOD SPRINGS, COLORADO. AS A WORKING DOCUMENT, THE PLAN RECOMMENDS STRAT...

Carbon dynamics of river corridors and the effects of human alterations

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

Wohl, Ellen; Hall, Robert O.; Lininger, Katherine B.

Research in stream metabolism, gas exchange, and sediment dynamics indicates that rivers are an active component of the global carbon cycle and that river form and process can influence partitioning of terrestrially derived carbon among the atmosphere, geosphere, and ocean. Here we develop a conceptual model of carbon dynamics (inputs, outputs, and storage of organic carbon) within a river corridor, which includes the active channel and the riparian zone. The exchange of carbon from the channel to the riparian zone represents potential for storage of transported carbon not included in the “active pipe” model of organic carbon (OC) dynamics inmore » freshwater systems. The active pipe model recognizes that river processes influence carbon dynamics, but focuses on CO2 emissions from the channel and eventual delivery to the ocean. We also review how human activities directly and indirectly alter carbon dynamics within river corridors. We propose that dams create the most significant alteration of carbon dynamics within a channel, but that alteration of riparian zones, including the reduction of lateral connectivity between the channel and riparian zone, constitutes the most substantial change of carbon dynamics in river corridors. We argue that the morphology and processes of a river corridor regulate the ability to store, transform, and transport OC, and that people are pervasive modifiers of river morphology and processes. The net effect of most human activities, with the notable exception of reservoir construction, appears to be that of reducing the ability of river corridors to store OC within biota and sediment, which effectively converts river corridors to OC sources rather than OC sinks. We conclude by summarizing knowledge gaps in OC dynamics and the implications of our findings for managing OC dynamics within river corridors.« less

Carbon dynamics of river corridors and the effects of human alterations

DOE PAGES

Wohl, Ellen; Hall, Robert O.; Lininger, Katherine B.; ...

2017-06-22

Research in stream metabolism, gas exchange, and sediment dynamics indicates that rivers are an active component of the global carbon cycle and that river form and process can influence partitioning of terrestrially derived carbon among the atmosphere, geosphere, and ocean. Here we develop a conceptual model of carbon dynamics (inputs, outputs, and storage of organic carbon) within a river corridor, which includes the active channel and the riparian zone. The exchange of carbon from the channel to the riparian zone represents potential for storage of transported carbon not included in the “active pipe” model of organic carbon (OC) dynamics inmore » freshwater systems. The active pipe model recognizes that river processes influence carbon dynamics, but focuses on CO2 emissions from the channel and eventual delivery to the ocean. We also review how human activities directly and indirectly alter carbon dynamics within river corridors. We propose that dams create the most significant alteration of carbon dynamics within a channel, but that alteration of riparian zones, including the reduction of lateral connectivity between the channel and riparian zone, constitutes the most substantial change of carbon dynamics in river corridors. We argue that the morphology and processes of a river corridor regulate the ability to store, transform, and transport OC, and that people are pervasive modifiers of river morphology and processes. The net effect of most human activities, with the notable exception of reservoir construction, appears to be that of reducing the ability of river corridors to store OC within biota and sediment, which effectively converts river corridors to OC sources rather than OC sinks. We conclude by summarizing knowledge gaps in OC dynamics and the implications of our findings for managing OC dynamics within river corridors.« less

Carbon dynamics of river corridors and the effects of human alterations

USGS Publications Warehouse

Wohl, Ellen; Hall, Robert O.; Lininger, Katherine B; Sutfin, Nicholas A.; Walters, David

2017-01-01

Research in stream metabolism, gas exchange, and sediment dynamics indicates that rivers are an active component of the global carbon cycle and that river form and process can influence partitioning of terrestrially derived carbon among the atmosphere, geosphere, and ocean. Here we develop a conceptual model of carbon dynamics (inputs, outputs, and storage of organic carbon) within a river corridor, which includes the active channel and the riparian zone. The exchange of carbon from the channel to the riparian zone represents potential for storage of transported carbon not included in the “active pipe” model of organic carbon (OC) dynamics in freshwater systems. The active pipe model recognizes that river processes influence carbon dynamics, but focuses on CO2 emissions from the channel and eventual delivery to the ocean. We also review how human activities directly and indirectly alter carbon dynamics within river corridors. We propose that dams create the most significant alteration of carbon dynamics within a channel, but that alteration of riparian zones, including the reduction of lateral connectivity between the channel and riparian zone, constitutes the most substantial change of carbon dynamics in river corridors. We argue that the morphology and processes of a river corridor regulate the ability to store, transform, and transport OC, and that people are pervasive modifiers of river morphology and processes. The net effect of most human activities, with the notable exception of reservoir construction, appears to be that of reducing the ability of river corridors to store OC within biota and sediment, which effectively converts river corridors to OC sources rather than OC sinks. We conclude by summarizing knowledge gaps in OC dynamics and the implications of our findings for managing OC dynamics within river corridors.

Branch classification: A new mechanism for improving branch predictor performance

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

Chang, P.Y.; Hao, E.; Patt, Y.

There is wide agreement that one of the most significant impediments to the performance of current and future pipelined superscalar processors is the presence of conditional branches in the instruction stream. Speculative execution is one solution to the branch problem, but speculative work is discarded if a branch is mispredicted. For it to be effective, speculative work is discarded if a branch is mispredicted. For it to be effective, speculative execution requires a very accurate branch predictor; 95% accuracy is not good enough. This paper proposes branch classification, a methodology for building more accurate branch predictors. Branch classification allows anmore » individual branch instruction to be associated with the branch predictor best suited to predict its direction. Using this approach, a hybrid branch predictor can be constructed such that each component branch predictor predicts those branches for which it is best suited. To demonstrate the usefulness of branch classification, an example classification scheme is given and a new hybrid predictor is built based on this scheme which achieves a higher prediction accuracy than any branch predictor previously reported in the literature.« less

Assessing the chemical contamination dynamics in a mixed land use stream system.

PubMed

Sonne, Anne Th; McKnight, Ursula S; Rønde, Vinni; Bjerg, Poul L

2017-11-15

Traditionally, the monitoring of streams for chemical and ecological status has been limited to surface water concentrations, where the dominant focus has been on general water quality and the risk for eutrophication. Mixed land use stream systems, comprising urban areas and agricultural production, are challenging to assess with multiple chemical stressors impacting stream corridors. New approaches are urgently needed for identifying relevant sources, pathways and potential impacts for implementation of suitable source management and remedial measures. We developed a method for risk assessing chemical stressors in these systems and applied the approach to a 16-km groundwater-fed stream corridor (Grindsted, Denmark). Three methods were combined: (i) in-stream contaminant mass discharge for source quantification, (ii) Toxic Units and (iii) environmental standards. An evaluation of the chemical quality of all three stream compartments - stream water, hyporheic zone, streambed sediment - made it possible to link chemical stressors to their respective sources and obtain new knowledge about source composition and origin. Moreover, toxic unit estimation and comparison to environmental standards revealed the stream water quality was substantially impaired by both geogenic and diffuse anthropogenic sources of metals along the entire corridor, while the streambed was less impacted. Quantification of the contaminant mass discharge originating from a former pharmaceutical factory revealed that several 100 kgs of chlorinated ethenes and pharmaceutical compounds discharge into the stream every year. The strongly reduced redox conditions in the plume result in high concentrations of dissolved iron and additionally release arsenic, generating the complex contaminant mixture found in the narrow discharge zone. The fingerprint of the plume was observed in the stream several km downgradient, while nutrients, inorganics and pesticides played a minor role for the stream health. The

From Shoestring Rills to Dendritic River Networks: Documenting the Evolution of River Basins Towards Geometric Similarity Through Divide Migration, Stream Capture and Lateral Branching

NASA Astrophysics Data System (ADS)

Beeson, H. W.; McCoy, S. W.; Willett, S.

2016-12-01

Erosional river networks dissect much of Earth's surface into drainage basins. Global scaling laws such as Hack's Law suggest that river basins trend toward a particular scale-invariant shape. While erosional instabilities arising from competition between advective and diffusive processes can explain why headwaters branch, the erosional mechanics linking larger scale network branching with evolution towards a characteristic river basin shape remain poorly constrained. We map river steepness and a proxy for the steady-state elevation of river networks, χ, in simulated and real landscapes with a large range in spatial scale (102 -106 m) but with similar inclined, planar surfaces at the time of incipient network formation. We document that the evolution from narrow rill-like networks to dendritic, leaf-shaped river basins follows from drainage area differences between catchments. These serve as instabilities that grow, leading to divide migration, stream capture, lateral branching and network reorganization. As Horton hypothesized, incipient networks formed down gradient on an inclined, planar surface have an unequal distribution of drainage area and nonuniformity in response times such that larger basins erode more rapidly and branch laterally via capture of adjacent streams with lower erosion rates. Positive feedback owing to increase in drainage area furthers the process of branching at the expense of neighboring rivers. We show that drainage area exchange and the degree of network reorganization has a significant effect on river steepness in the Dragon's Back Pressure Ridge, CA, the Sierra Nevada, CA, and the Rocky Mountain High Plains, USA. Similarly, metrics of basin shape reveal that basins are evolving from narrow basins towards more common leaf shapes. Our results suggest that divide migration and stream capture driven by erosional disequilibrium could be fundamental processes by which river basins reach their characteristic geometry and dendritic form.

Riparian influences on the biophysical characteristics of seston in headwater streams.

Treesearch

Scott R. Elliott; Robert J. Naiman; Peter A. Bisson

2004-01-01

Suspended particles (seston) in streams are an important source of nutrition for many invertebrates, forming a strong trophic link between plant and animal production. In forested regions the management of riparian corridors may alter alloehthonous and autochthonous contributions to streams, ultimately changing the biophysical characteristics of seston. This article...

Large-Scale Habitat Corridors for Biodiversity Conservation: A Forest Corridor in Madagascar.

PubMed

Ramiadantsoa, Tanjona; Ovaskainen, Otso; Rybicki, Joel; Hanski, Ilkka

2015-01-01

In biodiversity conservation, habitat corridors are assumed to increase landscape-level connectivity and to enhance the viability of otherwise isolated populations. While the role of corridors is supported by empirical evidence, studies have typically been conducted at small spatial scales. Here, we assess the quality and the functionality of a large 95-km long forest corridor connecting two large national parks (416 and 311 km2) in the southeastern escarpment of Madagascar. We analyze the occurrence of 300 species in 5 taxonomic groups in the parks and in the corridor, and combine high-resolution forest cover data with a simulation model to examine various scenarios of corridor destruction. At present, the corridor contains essentially the same communities as the national parks, reflecting its breadth which on average matches that of the parks. In the simulation model, we consider three types of dispersers: passive dispersers, which settle randomly around the source population; active dispersers, which settle only in favorable habitat; and gap-avoiding active dispersers, which avoid dispersing across non-habitat. Our results suggest that long-distance passive dispersers are most sensitive to ongoing degradation of the corridor, because increasing numbers of propagules are lost outside the forest habitat. For a wide range of dispersal parameters, the national parks are large enough to sustain stable populations until the corridor becomes severely broken, which will happen around 2065 if the current rate of forest loss continues. A significant decrease in gene flow along the corridor is expected after 2040, and this will exacerbate the adverse consequences of isolation. Our results demonstrate that simulation studies assessing the role of habitat corridors should pay close attention to the mode of dispersal and the effects of regional stochasticity.

Large-Scale Habitat Corridors for Biodiversity Conservation: A Forest Corridor in Madagascar

PubMed Central

Ramiadantsoa, Tanjona; Ovaskainen, Otso; Rybicki, Joel; Hanski, Ilkka

2015-01-01

In biodiversity conservation, habitat corridors are assumed to increase landscape-level connectivity and to enhance the viability of otherwise isolated populations. While the role of corridors is supported by empirical evidence, studies have typically been conducted at small spatial scales. Here, we assess the quality and the functionality of a large 95-km long forest corridor connecting two large national parks (416 and 311 km2) in the southeastern escarpment of Madagascar. We analyze the occurrence of 300 species in 5 taxonomic groups in the parks and in the corridor, and combine high-resolution forest cover data with a simulation model to examine various scenarios of corridor destruction. At present, the corridor contains essentially the same communities as the national parks, reflecting its breadth which on average matches that of the parks. In the simulation model, we consider three types of dispersers: passive dispersers, which settle randomly around the source population; active dispersers, which settle only in favorable habitat; and gap-avoiding active dispersers, which avoid dispersing across non-habitat. Our results suggest that long-distance passive dispersers are most sensitive to ongoing degradation of the corridor, because increasing numbers of propagules are lost outside the forest habitat. For a wide range of dispersal parameters, the national parks are large enough to sustain stable populations until the corridor becomes severely broken, which will happen around 2065 if the current rate of forest loss continues. A significant decrease in gene flow along the corridor is expected after 2040, and this will exacerbate the adverse consequences of isolation. Our results demonstrate that simulation studies assessing the role of habitat corridors should pay close attention to the mode of dispersal and the effects of regional stochasticity. PMID:26200351

Interior, underground corridor going to building 500 from the corridor ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior, underground corridor going to building 500 from the corridor connecting buildings 511 and 515. - Fitzsimons General Hospital, Infirmary, Northwest Corner of East Bushnell Avenue & South Page Street, Aurora, Adams County, CO

Corridor use by diverse taxa.

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

Haddad, Nick, M.; Browne, David, R.; Cunningham, Alan

2003-01-01

Haddad, N.M., D.R. Browne, A. Cunningham, B.J. Danielson, D.J. Levey, S. Sargent, and T. Spira. 2003. Corridor use by diverse taxa. Ecology, 84(3):609-615. One of the most popular approaches for maintaining populations and conserving biodiversity in fragmented landscapes is to retain or create corridors that connect otherwise isolated habitat patches. Working in large-scale, experimental landscapes in which open-habitat patches and corridors were created by harvesting pine forest, we showed that corridors direct movements of different types of species, including butterflies, small mammals, and bird dispersed plants, causing higher movement between connected than between unconnected patches. Corridors directed the movement ofmore » all 10 species studied, with all corridor effect sizes >68%. However, this corridor effect was significant for five species, not significant for one species, and inconclusive for four species because of small sample sizes. Although we found no evidence that corridors increase emigration from a patch, our results show that movements of disparate taxa with broadly different life histories and functional roles are directed by corridors.« less

Seasonal Dynamics of River Corridor Exchange Across the Continental United States

NASA Astrophysics Data System (ADS)

Gomez-Velez, J. D.; Harvey, J. W.; Scott, D.; Boyer, E. W.; Schmadel, N. M.

2017-12-01

River corridors store and convey mass and energy from landscapes to the ocean, altering water quality and ecosystem functioning at the local, reach, and watershed scales. As water moves through river corridors from headwaters streams to coastal estuaries, dynamic exchange between the river channel and its adjacent riparian, floodplain, and hyporheic zones, combined with ponded waters such as lakes and reservoirs, results in the emergence of hot spots and moments for biogeochemical transformations. In this work, we used the model Networks with EXchange and Subsurface Storage (NEXSS) to estimate seasonal variations in river corridor exchange fluxes and residence times along the continental United States. Using a simple routing scheme, we translate these estimates into a cumulative measure of river corridor connectivity at the watershed scale, differentiating the contributions of hyporheic zones, floodplains, and ponded waters. We find that the relative role of these exchange subsystems changes seasonally, driven by the intra-seasonal variability of discharge. In addition, we find that seasonal variations in discharge and the biogeochemical potential of hyporheic zones are out of phase. This behavior results in a significant reduction in hyporheic water quality functions during high flows and emphasizes the potential importance of reconnecting floodplains for managing water quality during seasonal high flows. Physical parameterizations of river corridor processes are critical to model and predict water quality and to sustainably manage water resources under present and future socio-economic and climatic conditions. Parsimonious models like NEXSS can play a key role in the design, implementation, and evaluation of sustainable management practices that target both water quantity and quality at the scale of the nation. This research is a product of the John Wesley Powell Center River Corridor Working Group.

Small mammal habitat use within restored riparian habitats adjacent to channelized streams in Mississippi

USDA-ARS?s Scientific Manuscript database

Riparian zones of channelized agricultural streams in northwestern Mississippi typically consist of narrow vegetative corridors low in habitat diversity and lacking riparian wetlands. Land clearing practices and stream channelization has led to the development of gully erosion and further fragmenta...

Suspended-sediment yields and stream-channel processes on Judy's Branch watershed in the St. Louis Metro East region in Illinois

USGS Publications Warehouse

Straub, Timothy D.; Johnson, Gary P.; Roseboom, Donald P.; Sierra, Carlos R.

2006-01-01

Judy's Branch watershed, a small basin (8.64 square miles) in the St. Louis Metro East region in Illinois, was selected as a pilot site to determine suspended-sediment yields and stream-channel processes in the bluffs and American Bottoms (expansive low-lying valley floor in the region). Suspended-sediment and stream-chan-nel data collected and analyzed for Judy's Branch watershed are presented in this report to establish a baseline of data for water-resource managers to evaluate future stream rehabilitation and manage-ment alternatives. The sediment yield analysis determines the amount of sediment being delivered from the watershed and two subwatersheds: an urban tributary and an undeveloped headwater (pri-marily agricultural). The analysis of the subwater-sheds is used to compare the effects of urbanization on sediment yield to the river. The stream-channel contribution to sediment yield was determined by evaluation of the stream-channel processes operat-ing on the streambed and banks of Judy's Branch watershed. Bank stability was related to hydrologic events, bank stratigraphy, and channel geometry through model development and simulation. The average suspended-sediment yield from two upland subwatersheds (drainage areas of 0.23 and 0.40 sq.mi. was 1,163 tons per square mile per year (tons/sq.mi.-year) between July 2000 and June 2004. The suspended-sediment yield at the Route 157 station was 2,523 tons/sq.mi.-year, near the outlet of Judy's Branch watershed (drainage area = 8.33 sq.mi.). This is approximately 1,360 tons/sq.mi.-year greater than the average at the upland stations for the same time period. This result is unexpected in that, generally, the suspended-sediment yield decreases as the watershed area increases because of sediment stored in the channel and flood plain. The difference indicates a possible increase in yield from a source, such as bank retreat, and supports the concept that land-use changes increase stream-flows that may in turn result in

Stochastic ice stream dynamics

PubMed Central

Bertagni, Matteo Bernard; Ridolfi, Luca

2016-01-01

Ice streams are narrow corridors of fast-flowing ice that constitute the arterial drainage network of ice sheets. Therefore, changes in ice stream flow are key to understanding paleoclimate, sea level changes, and rapid disintegration of ice sheets during deglaciation. The dynamics of ice flow are tightly coupled to the climate system through atmospheric temperature and snow recharge, which are known exhibit stochastic variability. Here we focus on the interplay between stochastic climate forcing and ice stream temporal dynamics. Our work demonstrates that realistic climate fluctuations are able to (i) induce the coexistence of dynamic behaviors that would be incompatible in a purely deterministic system and (ii) drive ice stream flow away from the regime expected in a steady climate. We conclude that environmental noise appears to be crucial to interpreting the past behavior of ice sheets, as well as to predicting their future evolution. PMID:27457960

20. Readiness Crew Building interior, upper level corridor. This corridor ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. Readiness Crew Building interior, upper level corridor. This corridor runs from northwest to southeast. Photograph taken at the northwest end looking southeast. Lyon - Whiteman Air Force Base, Bomber Alert Facility S-6, 1300 Alert Road, Knob Noster, Johnson County, MO

Factors of Stream Instability in Urban Centres of Southern Nigeria: Case Study of Port Harcourt City River Systems.

NASA Astrophysics Data System (ADS)

Amangabara, G. T.

2006-05-01

There are two main drainage rivers in the Port Harcourt Metropolis - The Ntamogba and the Woji creek (Abam, 2004). There are a few other drainage rivers that are equally important e.g. the Nwaja River that drains Rumukalagbor, Elekahia, New GRA Phases IV and V, Presidential Housing Estate and Sun Ray publications Area of Aba Road. These river systems drain the entire Port Harcourt City dividing the City into three major drainage zones. Since the discovery of oil in Nigeria in the 1950s, the country has been suffering the negative environmental consequences of oil development. The growth of the country's oil industry, combined with population explosion and a lack of environmental regulations, led to substantial damage to Nigeria's environment, especially in the Niger Delta region, the center of the country's oil industry. Uncontrolled population movement as well as spontaneous housing development on marginal lands such as stream corridors, has led to the degradation of all major stream channels in the Nation's oil capital - Port Harcourt City. The longitudinal profiles and cross sections of reaches of three major streams (Ntamogba, Nwaja, and Oginigba streams) were investigated. Land use maps of 1979 1999 and 2004 were used. Our result showed that 1). Almost all of the stream corridors have been built up without adequate plan 2). The natural grades have been distorted by channelisation for the purpose of flood evacuation without geomorphic consideration .3). Our research also shows that the interface of saline water and fresh water has extended upstream affecting urban infrastructure. 4) localized damming and sedimentation behind hydraulic structures were common occurrences) our overall result indicate that two episodes of channel incision on Oginigba stream had increased slope reduced sinuosity increased entrenchment and reduce width-depth ratio . Conclusively the factors of the instability of theses urban streams are manly the processes of urbanization which

24. Interior view of entrance corridor looking down east corridor; ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. Interior view of entrance corridor looking down east corridor; showing unoccupied corner office space and stairs going down to lower floor; center of main section of building on main floor; view to northeast. - Ellsworth Air Force Base, Group Administration & Secure Storage Building, 2372 Westover Avenue, Blackhawk, Meade County, SD

A meta-analytic review of corridor effectiveness.

PubMed

Gilbert-Norton, Lynne; Wilson, Ryan; Stevens, John R; Beard, Karen H

2010-06-01

Using corridors for conservation is increasing despite a lack of consensus on their efficacy. Specifically, whether corridors increase movement of plants and animals between habitat fragments has been addressed on a case-by-case basis with mixed results. Because of the growing number of well-designed experiments that have addressed this question, we conducted a meta-analysis to determine whether corridors increase movement; whether corridor effectiveness differs among taxa; how recent changes in experimental design have influenced findings; and whether corridor effectiveness differs between manipulative and natural experiments. To conduct our meta-analysis, we analyzed 78 experiments from 35 studies using a conservative hierarchical Bayesian model that accounts for hierarchical and sampling dependence. We found a highly significant result that corridors increase movement between habitat patches by approximately 50% compared to patches that are not connected with corridors. We found that corridors were more important for the movement of invertebrates, nonavian vertebrates, and plants than they were for birds. Recent methodological advances in corridor experiments, such as controlling for the area added by corridors, did not influence whether corridors increased movement, whereas controlling for the distance between source and connected or unconnected recipient patches decreased movement through corridors. After controlling for taxa differences and whether studies controlled for distance in experimental design, we found that natural corridors (those existing in landscapes prior to the study) showed more movement than manipulated corridors (those created and maintained for the study). Our results suggest that existing corridors increase species movement in fragmented landscapes and that efforts spent on maintaining and creating corridors are worthwhile.

18. Readiness Crew Building interior, lower level corridor. This corridor ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

18. Readiness Crew Building interior, lower level corridor. This corridor is located in the southwest side of the building and runs from southeast to northwest; view looking northwest from the exit door at the southeast end. Lyon - Whiteman Air Force Base, Bomber Alert Facility S-6, 1300 Alert Road, Knob Noster, Johnson County, MO

Evolved atmospheric entry corridor with safety factor

NASA Astrophysics Data System (ADS)

Liang, Zixuan; Ren, Zhang; Li, Qingdong

2018-02-01

Atmospheric entry corridors are established in previous research based on the equilibrium glide condition which assumes the flight-path angle to be zero. To get a better understanding of the highly constrained entry flight, an evolved entry corridor that considers the exact flight-path angle is developed in this study. Firstly, the conventional corridor in the altitude vs. velocity plane is extended into a three-dimensional one in the space of altitude, velocity, and flight-path angle. The three-dimensional corridor is generated by a series of constraint boxes. Then, based on a simple mapping method, an evolved two-dimensional entry corridor with safety factor is obtained. The safety factor is defined to describe the flexibility of the flight-path angle for a state within the corridor. Finally, the evolved entry corridor is simulated for the Space Shuttle and the Common Aero Vehicle (CAV) to demonstrate the effectiveness of the corridor generation approach. Compared with the conventional corridor, the evolved corridor is much wider and provides additional information. Therefore, the evolved corridor would benefit more to the entry trajectory design and analysis.

52. 2E corridor, from intersection of 2F corridor, second floor, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

52. 2E corridor, from intersection of 2F corridor, second floor, building 500, looking east - Offutt Air Force Base, Strategic Air Command Headquarters & Command Center, Headquarters Building, 901 SAC Boulevard, Bellevue, Sarpy County, NE

SDF1 regulates leading process branching and speed of migrating interneurons

PubMed Central

Lysko, Daniel E.; Putt, Mary; Golden, Jeffrey A.

2011-01-01

Cell migration is required for normal embryonic development, yet how cells navigate complex paths while integrating multiple guidance cues remains poorly understood. During brain development, interneurons migrate from the ventral ganglionic eminence to the cerebral cortex within several migratory streams. They must exit these streams to invade the cortical plate. While SDF1-signaling is necessary for normal interneuron stream migration, how they switch from tangential stream migration to invade the cortical plate is unknown. Here we demonstrate that SDF1-signaling reduces interneuron branching frequency by reducing cAMP levels via a Gi-signaling pathway using an in vitro mouse explant system, resulting in the maintenance of stream migration. Blocking SDF1-signaling, or increasing branching frequency, results in stream exit and cortical plate invasion in mouse brain slices. These data support a novel model to understand how migrating interneurons switch from tangential migration to invade the cortical plate in which reducing SDF1-signaling increases leading process branching and slows the migration rate, permitting migrating interneurons to sense cortically directed guidance cues. PMID:21289183

Integrated corridor management analysis, modeling, and simulation results for the test corridor.

DOT National Transportation Integrated Search

2008-06-01

This report documents the Integrated Corridor Management (ICM) Analysis Modeling and Simulation (AMS) tools and strategies used on a Test Corridor, presents results and lessons-learned, and documents the relative capability of AMS to support benefit-...

Potential negative ecological effects of corridors.

PubMed

Haddad, Nick M; Brudvig, Lars A; Damschen, Ellen I; Evans, Daniel M; Johnson, Brenda L; Levey, Douglas J; Orrock, John L; Resasco, Julian; Sullivan, Lauren L; Tewksbury, Josh J; Wagner, Stephanie A; Weldon, Aimee J

2014-10-01

Despite many studies showing that landscape corridors increase dispersal and species richness for disparate taxa, concerns persist that corridors can have unintended negative effects. In particular, some of the same mechanisms that underlie positive effects of corridors on species of conservation interest may also increase the spread and impact of antagonistic species (e.g., predators and pathogens), foster negative effects of edges, increase invasion by exotic species, increase the spread of unwanted disturbances such as fire, or increase population synchrony and thus reduce persistence. We conducted a literature review and meta-analysis to evaluate the prevalence of each of these negative effects. We found no evidence that corridors increase unwanted disturbance or non-native species invasion; however, these have not been well-studied concerns (1 and 6 studies, respectively). Other effects of corridors were more often studied and yielded inconsistent results; mean effect sizes were indistinguishable from zero. The effect of edges on abundances of target species was as likely to be positive as negative. Corridors were as likely to have no effect on antagonists or population synchrony as they were to increase those negative effects. We found 3 deficiencies in the literature. First, despite studies on how corridors affect predators, there are few studies of related consequences for prey population size and persistence. Second, properly designed studies of negative corridor effects are needed in natural corridors at scales larger than those achievable in experimental systems. Third, studies are needed to test more targeted hypotheses about when corridor-mediated effects on invasive species or disturbance may be negative for species of management concern. Overall, we found no overarching support for concerns that construction and maintenance of habitat corridors may result in unintended negative consequences. Negative edge effects may be mitigated by widening

I-10 national freight corridor study : phase II report, corridor ITS architecture.

DOT National Transportation Integrated Search

2007-01-01

The Interstate 10 National Freight Corridor extends : across the eight states that form the southern boundary : of the contiguous 48 states. From west to east, the : corridor crosses parts of California, Arizona, New : Mexico, Texas, Louisiana, Missi...

Calculating Toxic Corridors.

DTIC Science & Technology

1980-11-01

59 programmable calculator . Method 1 will most likely be used if there is a toxic corridor length table for the chemical; Method 2 if there is no table...experience of the forecaster in making this forecast, availability of a toxic corridor length table for the released chemical, and availability of a TI

Preimpoundment water quality of Raystown Branch Juniata River and six tributary streams, south-central Pennsylvania

USGS Publications Warehouse

Williams, Donald R.

1976-01-01

The Raystown Branch Juniata River watershed, which is the main water source for Raystown Lake, is a 960-square-mile (2,490 square kilometres) drainage basin in south-central Pennsylvania. Preimpoundment water-quality data were collected on the Raystown Branch and six tributary st.reams in the basin. Specific conductance values varied inversely with water discharge. The pH values were extremely low only at the Shoup Run site. Dissolved oxygen concentrations observed at all sites indicated a relatively high oxygen saturation level throughout the year. Seasonal variations in nitrate-N and orthophosphate-P levels were measured at the main inflow station at Saxton, Pa. The highest concentrations of nitrate-N and orthophosphate-P occurred in the winter and spring months and the lowest concentrations were measured dur:l.ng the swnmer and fall. Bacteriological data indicated no excessive -amounts of fecal matter present at the inflows. Soil samples collected at four sites in the impoundment area were predominantly of the Barbour, Philo, and Basher series, which are considered to be highly fertile soils with silt-loam and sandy~loam textures. Morphological features of the lake basin and low nutrient levels at the inflows should prevent excessive weed growth around the lake perimeter.

Corridor incident management (CIM)

DOT National Transportation Integrated Search

2007-09-01

The objective of the Corridor Incident Management (CIM) research project was to develop and demonstrate a set of multi-purpose methods, tools and databases to improve corridor incident management in Tennessee, relying primarily on resources already a...

Corridors cause differential seed predation.

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

Orrock, John L.; Damschen, Ellen I.

2005-06-01

Orrock, John, L., and Ellen I. Damschen. 2005. Corridors cause differential seed predation. Ecol. Apps. 15(3):793-798. Abstract. Corridors that connect disjunct populations are heavily debated in conservation, largely because the effects of corridors have rarely been evaluated by replicated, large-scale studies. Using large-scale experimental landscapes, we found that, in addition to documented positive effects, corridors also have negative impacts on bird-dispersed plants by affecting seed predation, and that overall predation is a function of the seeds primary consumer (rodents or arthropods). Both large-seeded Prunus serotina and small-seeded Rubus allegheniensis experienced greater predation in connected patches. However, P. serotina experienced significantlymore » less seed predation compared to R. allegheniensis in unconnected patches, due to decreased impacts of rodent seed predators on this large-seeded species. Viewed in light of previous evidence that corridors have beneficial impacts by increasing pollination and seed dispersal, this work demonstrates that corridors may have both positive and negative effects for the same plant species at different life stages. Moreover, these effects may differentially affect plant species within the same community: seeds primarily consumed by rodents suffer less predation in unconnected patches. By shifting the impact of rodent and arthropod seed predators, corridors constructed for plant conservation could lead to shifts in the seed bank.« less

Monitoring vegetation water uptake in a semiarid riparian corridor

NASA Astrophysics Data System (ADS)

Robinson, J.; Ochoa, C. G.; Leonard, J.

2015-12-01

With a changing global climate and growing demand for water throughout the world, responsible and sustainable land and water resource management practices are becoming increasingly important. Accounting for the amount of water used by riparian vegetation is a critical element for better managing water resources in arid and semiarid environments. The objective of this study was to determine water uptake by selected riparian vegetative species in a semiarid riparian corridor in North-Central Oregon. Exo-skin sap flow sensors (Dynamax, Houston, TX, U.S.A.) were used to measure sap flux in red alder (Alnus rubra) trees, the dominant overstory vegetation at the field site. Xylem sap flow data was collected from selected trees at the field site and in a greenhouse setting. Transpiration rates were determined based on an energy balance method, which makes it possible to estimate the mass flow of sap by measuring the velocity of electrical heat pulses through the plant stem. Preliminary field results indicate that red alder tree branches of about 1 inch diameter transpire between 2 and 6 kg of water/day. Higher transpiration rates of up to 7.3 kg of water/day were observed under greenhouse conditions. Streamflow and stream water temperature, vegetation characteristics, and meteorological data were analyzed in conjunction with transpiration data. Results of this study provide insight on riparian vegetation water consumption in water scarce ecosystems. This study is part of an overarching project focused on climate-vegetation interactions and ecohydrologic processes in arid and semiarid landscapes.

Corridor One:An Integrated Distance Visualization Enuronments for SSI+ASCI Applications

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

Christopher R. Johnson, Charles D. Hansen

2001-10-29

The goal of Corridor One: An Integrated Distance Visualization Environment for ASCI and SSI Application was to combine the forces of six leading edge laboratories working in the areas of visualization and distributed computing and high performance networking (Argonne National Laboratory, Lawrence Berkeley National Laboratory, Los Alamos National Laboratory, University of Illinois, University of Utah and Princeton University) to develop and deploy the most advanced integrated distance visualization environment for large-scale scientific visualization and demonstrate it on applications relevant to the DOE SSI and ASCI programs. The Corridor One team brought world class expertise in parallel rendering, deep image basedmore » rendering, immersive environment technology, large-format multi-projector wall based displays, volume and surface visualization algorithms, collaboration tools and streaming media technology, network protocols for image transmission, high-performance networking, quality of service technology and distributed computing middleware. Our strategy was to build on the very successful teams that produced the I-WAY, ''Computational Grids'' and CAVE technology and to add these to the teams that have developed the fastest parallel visualizations systems and the most widely used networking infrastructure for multicast and distributed media. Unfortunately, just as we were getting going on the Corridor One project, DOE cut the program after the first year. As such, our final report consists of our progress during year one of the grant.« less

Corridor Use Predicted from Behaviors at Habitat Boundaries.

PubMed

Haddad, Nick M

1999-02-01

Through empirical studies and simulation, I demonstrate how simple behaviors can be used in lieu of detailed dispersal studies to predict the effects of corridors on interpatch movements. Movement paths of three butterfly species were measured in large (1.64 ha) experimental patches of open habitat, some of which were connected by corridors. Butterflies that "reflected" off boundaries between open patches and the surrounding forest also emigrated from patches through corridors at rates higher than expected from random movement. This was observed for two open-habitat species, Eurema nicippe and Phoebis sennae; however, edges and corridors had no effect on a habitat generalist, Papilio troilus. Behaviorally based simulation models, which departed from correlated random walks only at habitat boundaries, predicted that corridors increase interpatch movement rates of both open-habitat species. Models also predicted that corridors have proportionately greater effects as corridor width increases, that movement rates increase before leveling off as corridor width increases, and that corridor effects decrease as patch size increases. This study suggests that corridors direct movements of habitat-restricted species and that local behaviors may be used to predict the conservation potential of corridors in fragmented landscapes.

Magellan aerobraking periapse corridor design

NASA Technical Reports Server (NTRS)

Cook, Richard A.; Lyons, Daniel T.

1992-01-01

One extended mission idea for the Magellan project uses aerobraking techniques to circularize the current orbit. A major technical issue in this proposal is the design of the periapse altitude corridor. Aerobraking would cause a number of significant side effects on both the spacecraft and ground system. Heating and aerodynamic torques on the spacecraft are key issues, as are the corridor control maneuver frequency and aerobrake duration. Spacecraft and ground systems operational limits have been identified in an attempt to constrain the corridor design. A simulation program has been developed to model the aerobraking corridor control process. This paper presents study results using this program which relate to the feasibility of this aerobraking concept.

Long Island Smart Energy Corridor

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

Mui, Ming

The Long Island Power Authority (LIPA) has teamed with Stony Brook University (Stony Brook or SBU) and Farmingdale State College (Farmingdale or FSC), two branches of the State University of New York (SUNY), to create a “Smart Energy Corridor.” The project, located along the Route 110 business corridor on Long Island, New York, demonstrated the integration of a suite of Smart Grid technologies from substations to end-use loads. The Smart Energy Corridor Project included the following key features: -TECHNOLOGY: Demonstrated a full range of smart energy technologies, including substations and distribution feeder automation, fiber and radio communications backbone, advanced meteringmore » infrastructure (AM”), meter data management (MDM) system (which LIPA implemented outside of this project), field tools automation, customer-level energy management including automated energy management systems, and integration with distributed generation and plug-in hybrid electric vehicles. -MARKETING: A rigorous market test that identified customer response to an alternative time-of-use pricing plan and varying levels of information and analytical support. -CYBER SECURITY: Tested cyber security vulnerabilities in Smart Grid hardware, network, and application layers. Developed recommendations for policies, procedures, and technical controls to prevent or foil cyber-attacks and to harden the Smart Grid infrastructure. -RELIABILITY: Leveraged new Smart Grid-enabled data to increase system efficiency and reliability. Developed enhanced load forecasting, phase balancing, and voltage control techniques designed to work hand-in-hand with the Smart Grid technologies. -OUTREACH: Implemented public outreach and educational initiatives that were linked directly to the demonstration of Smart Grid technologies, tools, techniques, and system configurations. This included creation of full-scale operating models demonstrating application of Smart Grid technologies in business and

In-stream biotic control on nutrient biogeochemistry in a forested sheadwater tream, West Fork of Walker Branch

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

Roberts, Brian J; Mulholland, Patrick J

2007-01-01

A growing body of evidence demonstrates the importance of in-stream processing in regulating nutrient export, yet the influence of temporal variability in stream metabolism on net nutrient uptake has not been explicitly addressed. Streamwater DIN and SRP concentrations in Walker Branch, a first-order deciduous forest stream in eastern Tennessee, show a repeated pattern of annual maxima in summer and biannual minima in spring and autumn. Temporal variations in catchment hydrologic flowpaths result in lower winter and higher summer nutrient concentrations, but do not explain the spring and autumn nutrient minima. Ambient nutrient uptake rates were measured 2-3 times per weekmore » over an 18-mo period and compared to daily rates of gross primary production (GPP) and ecosystem respiration (ER) to examine the influence of in-stream biotic activity on nutrient export. GPP and ER rates explained 85% of the variation in net DIN retention with high net NO3- uptake (and lower net NH4+ release) rates occurring during spring and autumn and net DIN release in summer. Diel nutrient concentration patterns were examined several times throughout the year to determine the relative importance of autotrophic and heterotrophic activity on net nutrient uptake. High spring GPP corresponded to daily decreases in NO3- over the illuminated hours resulting in high diel NO3- amplitude which dampened as the canopy closed. GPP explained 91% of the variance in diel NO3- amplitude. In contrast, the autumn nutrient minima was largely explained by heterotrophic respiration since GPP remained low and little diel NO3- variation was observed during the autumn.« less

Research notes : are safety corridors really safe? Evaluation of the corridor safety improvement program.

DOT National Transportation Integrated Search

1998-08-26

High accident frequencies on Oregons highway corridors are of concern to the Oregon Department of Transportation (ODOT). : ODOT adopted the Corridor Safety Improvement Program as part of an overall program of safety improvements using federal and ...

Prediction of stream fish assemblages from land use characteristics: implications for cost-effective design of monitoring programmes.

PubMed

Kristensen, Esben Astrup; Baattrup-Pedersen, Annette; Andersen, Hans Estrup

2012-03-01

Increasing human impact on stream ecosystems has resulted in a growing need for tools helping managers to develop conservations strategies, and environmental monitoring is crucial for this development. This paper describes the development of models predicting the presence of fish assemblages in lowland streams using solely cost-effective GIS-derived land use variables. Three hundred thirty-five stream sites were separated into two groups based on size. Within each group, fish abundance data and cluster analysis were used to determine the composition of fish assemblages. The occurrence of assemblages was predicted using a dataset containing land use variables at three spatial scales (50 m riparian corridor, 500 m riparian corridor and the entire catchment) supplemented by a dataset on in-stream variables. The overall classification success varied between 66.1-81.1% and was only marginally better when using in-stream variables than when applying only GIS variables. Also, the prediction power of a model combining GIS and in-stream variables was only slightly better than prediction based solely on GIS variables. The possibility of obtaining precise predictions without using costly in-stream variables offers great potential in the design of monitoring programmes as the distribution of monitoring sites along a gradient in ecological quality can be done at a low cost.

Integrated corridor management initiative : demonstration phase evaluation – Dallas corridor performance analysis test plan.

DOT National Transportation Integrated Search

2012-08-01

This report presents the test plan for conducting the Corridor Performance Analysis for the United States Department of Transportation (U.S. DOT) evaluation of the Dallas U.S. 75 Integrated Corridor Management (ICM) Initiative Demonstration. The ICM ...

Towards a definition of biological corridor

Treesearch

D.K. Rosenberg; B.R. Noon; E.C. Meslow

1995-01-01

Lack of clear, unambiguous criteria that distinguishes a linear habitat patch as a corridor contributes to controversy over the value of corridors for wildlife conservation. The definitions of biological corridors have been vague or inconsistent, and often they confound form and function. Explicit criteria that can differentiate between a linear habitat patch and a...

Corridors promote fire via connectivity and edge effects.

PubMed

Brudvig, Lars A; Wagner, Stephanie A; Damschen, Ellen I

2012-04-01

Landscape corridors, strips of habitat that connect otherwise isolated habitat patches, are commonly employed during management of fragmented landscapes. To date, most reported effects of corridors have been positive; however, there are long-standing concerns that corridors may have unintended consequences. Here, we address concerns over whether corridors promote propagation of disturbances such as fire. We collected data during prescribed fires in the world's largest and best replicated corridor experiment (Savannah River Site, South Carolina, USA), six -50-ha landscapes of open (shrubby/herbaceous) habitat within a pine plantation matrix, to test several mechanisms for how corridors might influence fire. Corridors altered patterns of fire temperature through a direct connectivity effect and an indirect edge effect. The connectivity effect was independent of fuel levels and was consistent with a hypothesized wind-driven "bellows effect." Edges, a consequence of corridor implementation, elevated leaf litter (fuel) input from matrix pine trees, which in turn increased fire temperatures. We found no evidence for corridors or edges impacting patterns of fire spread: plots across all landscape positions burned with similar probability. Impacts of edges and connectivity on fire temperature led to changes in vegetation: hotter-burning plots supported higher bunch grass cover during the field season after burning, suggesting implications for woody/herbaceous species coexistence. To our knowledge, this represents the first experimental evidence that corridors can modify landscape-scale patterns of fire intensity. Corridor impacts on fire should be carefully considered during landscape management, both in the context of how corridors connect or break distributions of fuels and the desired role of fire as a disturbance, which may range from a management tool to an agent to be suppressed. In our focal ecosystem, longleaf pine woodland, corridors might provide a previously

Integrated corridor management initiative : demonstration phase evaluation – San Diego corridor performance analysis test plan.

DOT National Transportation Integrated Search

2012-08-01

This report presents the test plan for conducting the Corridor Performance Analysis for the United States Department of Transportation (U.S. DOT) evaluation of the San Diego Integrated Corridor Management (ICM) Initiative Demonstration. The ICM proje...

How Corridors Reduce Indigo Bunting Nest Success.

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

Weldon, Aimee, J.

2006-08-01

Abstract: Corridors are a popular strategy to conserve biodiversity and promote gene flow in fragmented landscapes. Corridor effectiveness has been bolstered by the fact that no empirical field studies have shown negative effects on populations or communities. I tested the hypothesis that corridors increase nest predation in connected habitat fragments relative to unconnected fragments. I evaluated this hypothesis in a large-scale experimental system of open-habitat fragments that varied in shape and connectivity. Corridors increased nest predation rates in connected fragments relative to unconnected fragments with lower edge:area ratios. Nest predation rates were similar between connected and unconnected fragments with highermore » edge:area ratios. These results suggest that the increase in predator activity is largely attributable to edge effects incurred through the addition of a corridor. This is the first field study to demonstrate that corridors can negatively impact animal populations occupying connected fragments.« less

400 SOUTH CORRIDOR ASSESSMENT [2014

DOT National Transportation Integrated Search

2014-09-22

The goal of the 400 S Corridor Assessment study is to evaluate current and future traffic and transit performance along the new light rail line corridors and at major intersections in Salt Lake Citys Downtown and University of Utah areas. The fiel...

The significance of small streams

NASA Astrophysics Data System (ADS)

Wohl, Ellen

2017-09-01

Headwaters, defined here as first- and secondorder streams, make up 70%‒80% of the total channel length of river networks. These small streams exert a critical influence on downstream portions of the river network by: retaining or transmitting sediment and nutrients; providing habitat and refuge for diverse aquatic and riparian organisms; creating migration corridors; and governing connectivity at the watershed-scale. The upstream-most extent of the channel network and the longitudinal continuity and lateral extent of headwaters can be difficult to delineate, however, and people are less likely to recognize the importance of headwaters relative to other portions of a river network. Consequently, headwaters commonly lack the legal protections accorded to other portions of a river network and are more likely to be significantly altered or completely obliterated by land use.

Remote sensing impact on corridor selection and placement

NASA Technical Reports Server (NTRS)

Thomson, F. J.; Sellman, A. N.

1975-01-01

Computer-aided corridor selection techniques, utilizing digitized data bases of socio-economic, census, and cadastral data, and developed for highway corridor routing are considered. Land resource data generated from various remote sensing data sources were successfully merged with the ancillary data files of a corridor selection model and prototype highway corridors were designed using the combined data set. Remote sensing derived information considered useful for highway corridor location, special considerations in geometric correction of remote sensing data to facilitate merging it with ancillary data files, and special interface requirements are briefly discussed.

Corridor use by Asian elephants.

PubMed

Pan, Wenjing; Lin, Liu; Luo, Aidong; Zhang, Li

2009-06-01

There are 18 km of Kunming-Bangkok Highway passing through the Mengyang Nature Reserve of Xishuangbanna National Nature Reserve in Yunnan Province, China. From September 2005 to September 2006 the impact of this highway on movement of wild Asian elephants between the eastern and western part of the nature reserve was studied using track transecting, rural surveys and direct monitoring. Our results showed that the number of crossroad corridors used by Asian elephants diminished from 28 to 23 following the construction of the highway. In some areas, the elephant activity diminished or even disappeared, which indicated a change in their home ranges. The utilization rate of artificial corridors was 44%. We also found that elephants preferred artificial corridors that were placed along their original corridors. During the research, wild elephants revealed their adaptation to the highway. They were found walking across the highway road surface many times and for different reasons. We suggest that the highway management bureau should revise their management strategies to mitigate the potential risks caused by elephants on the road for the safety of the public and to protect this endangered species from harm. It is also very important to protect and maintain current Asian elephants corridors in this region. © 2009 ISZS, Blackwell Publishing and IOZ/CAS.

46 CFR 108.161 - Dead end corridors.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Dead end corridors. 108.161 Section 108.161 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Means of Escape § 108.161 Dead end corridors. No dead end corridor...

46 CFR 108.161 - Dead end corridors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Dead end corridors. 108.161 Section 108.161 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Means of Escape § 108.161 Dead end corridors. No dead end corridor...

46 CFR 108.161 - Dead end corridors.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Dead end corridors. 108.161 Section 108.161 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Means of Escape § 108.161 Dead end corridors. No dead end corridor...

46 CFR 108.161 - Dead end corridors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Dead end corridors. 108.161 Section 108.161 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Means of Escape § 108.161 Dead end corridors. No dead end corridor...

46 CFR 108.161 - Dead end corridors.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Dead end corridors. 108.161 Section 108.161 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Means of Escape § 108.161 Dead end corridors. No dead end corridor...

RISK CORRIDORS AND REINSURANCE IN HEALTH INSURANCE MARKETPLACES

PubMed Central

LAYTON, TIMOTHY J.; MCGUIRE, THOMAS G.; SINAIKO, ANNA D.

2016-01-01

Health Insurance Marketplaces established by the Affordable Care Act implement reinsurance and risk corridors. Reinsurance limits insurer costs associated with specific individuals, while risk corridors protect against aggregate losses. Both tighten the insurer’s distribution of expected costs. This paper compares the economic costs and consequences of reinsurance and risk corridors. We simulate the insurer’s cost distribution under reinsurance and risk corridors using data for a group of individuals likely to enroll in Marketplace plans from the Medical Expenditure Panel Survey. We compare reinsurance and risk corridors in terms of risk reduction and incentives for cost containment. We find that reinsurance and one-sided risk corridors achieve comparable levels of risk reduction for a given level of incentives. We also find that the policies being implemented in the Marketplaces (a mix of reinsurance and two-sided risk corridor policies) substantially limit insurer risk but perform similarly to a simpler stand-alone reinsurance policy. PMID:26973861

Corridors Increase Plant Species Richness at Large Scales

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

Damschen, Ellen I.; Haddad, Nick M.; Orrock,John L.

2006-09-01

Habitat fragmentation is one of the largest threats to biodiversity. Landscape corridors, which are hypothesized to reduce the negative consequences of fragmentation, have become common features of ecological management plans worldwide. Despite their popularity, there is little evidence documenting the effectiveness of corridors in preserving biodiversity at large scales. Using a large-scale replicated experiment, we showed that habitat patches connected by corridors retain more native plant species than do isolated patches, that this difference increases over time, and that corridors do not promote invasion by exotic species. Our results support the use of corridors in biodiversity conservation.

Corridors increase plant species richness at large scales.

PubMed

Damschen, Ellen I; Haddad, Nick M; Orrock, John L; Tewksbury, Joshua J; Levey, Douglas J

2006-09-01

Habitat fragmentation is one of the largest threats to biodiversity. Landscape corridors, which are hypothesized to reduce the negative consequences of fragmentation, have become common features of ecological management plans worldwide. Despite their popularity, there is little evidence documenting the effectiveness of corridors in preserving biodiversity at large scales. Using a large-scale replicated experiment, we showed that habitat patches connected by corridors retain more native plant species than do isolated patches, that this difference increases over time, and that corridors do not promote invasion by exotic species. Our results support the use of corridors in biodiversity conservation.

Contrasting past and current numbers of bears visiting Yellowstone cutthroat trout streams

USGS Publications Warehouse

Haroldson, Mark A.; Schwartz, Charles C.; Teisberg, Justin E.; Gunther, Kerry A.; Fortin, Jennifer K.; Robbins, Charles T.

2014-01-01

Spawning cutthroat trout (Oncorhynchus clarkii bouvieri) were historically abundant within tributary streams of Yellowstone Lake within Yellowstone National Park and were a highly digestible source of energy and protein for Yellowstone’s grizzly bears (Ursus arctos) and black bears (U. americanus). The cutthroat trout population has subsequently declined since the introduction of non-native lake trout (Salvelinus namaycush), and in response to effects of drought and whirling disease (Myxobolus cerebralis). The trout population, duration of spawning runs, and indices of bear use of spawning streams had declined in some regions of the lake by 1997–2000. We initiated a 3-year study in 2007 to assess whether numbers of spawning fish, black bears, and grizzly bears within and alongside stream corridors had changed since 1997– 2000. We estimated numbers of grizzly bears and black bears by first compiling encounter histories of individual bears visiting 48 hair-snag sites along 35 historically fished streams.We analyzed DNA encounter histories with Pradel-recruitment and Jolly-Seber (POPAN) capture-mark-recapture models. When compared to 1997–2000, the current number of spawning cutthroat trout per stream and the number of streams with cutthroat trout has decreased. We estimated that 48 (95% CI¼42–56) male and 23 (95% CI¼21–27) female grizzly bears visited the historically fished tributary streams during our study. In any 1- year, 46 to 59 independent grizzly bears (8–10% of estimated Greater Yellowstone Ecosystem population) visited these streams. When compared with estimates from the 1997 to 2000 study and adjusted for equal effort, the number of grizzly bears using the stream corridors decreased by 63%. Additionally, the number of black bears decreased between 64% and 84%. We also document an increased proportion of bears of both species visiting front-country (i.e., near human development) streams. With the recovery of cutthroat trout, we suggest bears

Integrated corridor management : ICM implementation guide

DOT National Transportation Integrated Search

2006-04-12

This Implementation Guidance for Integrated Corridor Management (ICM) has been developed as part of Phase 1 (Foundational Research) for the Federal Highway Administration and the Federal Transit Administration Integrated Corridor Management Initiativ...

Effective strategies for comprehensive corridor management

DOT National Transportation Integrated Search

2004-10-01

Despite the increasing importance of comprehensive corridor management at the state and local government level, questions remain regarding effective methods for developing and implementing corridor management plans. Further insight is also needed int...

Can dispersal mode predict corridor effects on plant parasites?

PubMed

Sullivan, Lauren L; Johnson, Brenda L; Brudvig, Lars A; Haddad, Nick M

2011-08-01

Habitat corridors, a common management strategy for increasing connectivity in fragmented landscapes, have experimentally validated positive influences on species movement and diversity. However, long-standing concerns that corridors could negatively impact native species by spreading antagonists, such as disease, remain largely untested. Using a large-scale, replicated experiment, we evaluated whether corridors increase the incidence of plant parasites. We found that corridor impacts varied with parasite dispersal mode. Connectivity provided by corridors increased incidence of biotically dispersed parasites (galls on Solidago odora) but not of abiotically dispersed parasites (foliar fungi on S. odora and three Lespedeza spp.). Both biotically and abiotically dispersed parasites responded to edge effects, but the direction of responses varied across species. Although our results require additional tests for generality to other species and landscapes, they suggest that, when establishing conservation corridors, managers should focus on mitigating two potential negative effects: the indirect effects of narrow corridors in creating edges and direct effects of corridors in enhancing connectivity of biotically dispersed parasites.

Map showing flood-prone areas, greater Denver area, Front Range Urban Corridor, Colorado

USGS Publications Warehouse

McCain, J.F.; Hotchkiss, W.R.

1975-01-01

The rapid growth of population in the Front Range Urban Corridor of Colorado is causing intense competition for available land resources. One form of competition posing serious problems in indiscriminate development on flood plains along creeks and rivers. Flood plains are natural features of the landscape developed by streams in carry water in excess of channel capacity. Although not used as often by the stream, flood plains are as much a part of the stream system as is the channel. Whenever man competes with this natural function of the flood plain he must inevitably pay the price through property damage and varying degrees of human suffering Flood damages in the United States have been estimated to average about \\$1 billion annually (American Public Works Association, 1966.) This tremendous waste of national resources is borne not only by those citizens in direct contact with floods but also to a lesser degree by all citizens through increased cost of public services. Thus, floods are of concern to the entire community, and solutions to existing or potential problems should be a community effort.

Estimating the Environmental Costs of Africa's Massive "Development Corridors".

PubMed

Laurance, William F; Sloan, Sean; Weng, Lingfei; Sayer, Jeffrey A

2015-12-21

In sub-Saharan Africa, dozens of major "development corridors" have been proposed or are being created to increase agricultural production [1-4], mineral exports [5-7], and economic integration. The corridors involve large-scale expansion of infrastructure such as roads, railroads, pipelines, and port facilities and will open up extensive areas of land to new environmental pressures [1, 4, 8]. We assessed the potential environmental impacts of 33 planned or existing corridors that, if completed, would total over 53,000 km in length and crisscross much of the African continent. We mapped each corridor and estimated human occupancy (using the distribution of persistent night-lights) and environmental values (endangered and endemic vertebrates, plant diversity, critical habitats, carbon storage, and climate-regulation services) inside a 50-km-wide band overlaid onto each corridor. We also assessed the potential for each corridor to facilitate increases in agricultural production. The corridors varied considerably in their environmental values, and many were only sparsely populated. Because of marginal soils or climates, some corridors appear to have only modest agricultural potential. Collectively, the corridors would bisect over 400 existing protected areas and could degrade a further ~1,800 by promoting habitat disruption near or inside the reserves. We conclude that many of the development corridors will promote serious and largely irreversible environmental changes and should proceed only if rigorous mitigation and protection measures can be employed. Some planned corridors with high environmental values and limited agricultural benefits should possibly be cancelled altogether. VIDEO ABSTRACT. Copyright © 2015 Elsevier Ltd. All rights reserved.

Influence of riparian alteration on canopy coverage and macrophyte abundance in Southeastern USA blackwater streams

Treesearch

Dean E. Fletcher; S. David Wilkins; J.V. McArthur; Gary K. Meffe

2000-01-01

Two tributary streams (Fourmile branch and Pen branch) located on the US Department of Energy's Savannah river site in west-central South Carolina, USA received thermal discharges from nuclear production reactors for over 30 years. Effluent releases produced stream water temperatures of over 50°C and stream flows of ten times above their base level. Consequently,...

Complexity Analysis of Traffic in Corridors-in-the-Sky

NASA Technical Reports Server (NTRS)

Xue, Min; Zelinski, Shannon Jean

2010-01-01

The corridors-in-the-sky concept imitates the highway system in ground transportation. The benefit expected from a corridor relies on its capability of handling high density traffic with negligible controller workload, the acceptance of extra fuel or distance, and the complexity reduction in underlying sectors. This work evaluates a selected corridor from these perspectives through simulations. To examine traffic inside the corridor, a corridor traffic simulation tool that can resolve conflicts is developed using C language. Prescribed conflict resolution maneuvers mimic corridor users behaviors and conflict resolution counts measure complexity. Different lane options and operational policies are proposed to examine their impacts on complexity. Fuel consumption is calculated and compared for corridor traffic. On the other hand, to investigate the complexity of non-corridor traffic in underlying sectors, the existing Airspace Concept Evaluation System tool is utilized along with the Automated Airspace Concept tool. The number of conflict resolutions is examined and treated as the complexity measurement. The results show heavy traffic can be managed with low complexity for a historical traffic schedule simulated with appropriate operational policies and lane options. For instance, with 608 flights and peak aircraft count of 100, only 84 actions need to be taken in a 24-hour period to resolve the conflicts for an 8-lane corridor. Compared with the fuel consumptions with great circle trajectories, the simulation of corridor traffic shows that the total extra fuel for corridor flights is 26,373 gallons, or 2.76%, which is 0.38% less than flying filed flight plans. Without taking climb and descent portions of corridor traffic, the complexity of underlying sectors is reduced by 17.71%. However the climb and descent portions will eliminate the reduction and the overall complexity of sectors is actually increased by 9.14%.

45 CFR 153.530 - Risk corridors data requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 153.530 Public Welfare Department of Health and Human Services REQUIREMENTS RELATING TO HEALTH CARE ACCESS STANDARDS RELATED TO REINSURANCE, RISK CORRIDORS, AND RISK ADJUSTMENT UNDER THE AFFORDABLE CARE ACT Health Insurance Issuer Standards Related to the Risk Corridors Program § 153.530 Risk corridors...

45 CFR 153.530 - Risk corridors data requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 153.530 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES REQUIREMENTS RELATING TO HEALTH CARE ACCESS STANDARDS RELATED TO REINSURANCE, RISK CORRIDORS, AND RISK ADJUSTMENT UNDER THE AFFORDABLE CARE ACT Health Insurance Issuer Standards Related to the Risk Corridors Program § 153.530 Risk corridors...

45 CFR 153.530 - Risk corridors data requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 153.530 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES REQUIREMENTS RELATING TO HEALTH CARE ACCESS STANDARDS RELATED TO REINSURANCE, RISK CORRIDORS, AND RISK ADJUSTMENT UNDER THE AFFORDABLE CARE ACT Health Insurance Issuer Standards Related to the Risk Corridors Program § 153.530 Risk corridors...

I-880 Integrated Corridor Management Concept of Operation : Final Submittal: Concept of Operations for the I-880 Corridor in Oakland, California

DOT National Transportation Integrated Search

2008-03-31

This report describes the draft Concept of Operations that has been developed for the Integrated Corridor Mobility (ICM) program by the I-880 corridor team. The I-880 corridor team has defined this Concept of Operations (ConOps) based on two primary ...

Hospital staff corridor conversations: work in passing.

PubMed

González-Martínez, Esther; Bangerter, Adrian; Lê Van, Kim; Navarro, Cécile

2016-03-01

First, to document the prevalence of corridor occupations and conversations among the staff of a hospital clinic, and their main features. Second, to examine the activities accomplished through corridor conversations and their interactional organization. Despite extensive research on mobility in hospital work, we still know fairly little about the prevalence and features of hospital staff corridor conversations and how they are organized. We conducted a study combining descriptive statistical analysis and multimodal conversation analysis of video recordings of staff corridor practices in a hospital outpatient clinic in Switzerland. In 2012, we collected 59 hours of video recordings in a corridor of a hospital clinic. We coded and statistically analysed the footage that showed the clinic staff exclusively. We also performed qualitative multimodal conversation analysis on a selection of the recorded staff conversations. Corridor occupations by the clinic staff are frequent and brief and rarely involve stops. Talk events (which include self-talk, face-to-face conversations and telephone conversations) during occupations are also brief and mobile, overwhelmingly focus on professional topics and are particularly frequent when two or more staff members occupy the corridor. The conversations present several interactional configurations and comprise an array of activities consequential to the provision of care and work organization. These practices are related to the fluid work organization of a spatially distributed team in a fast-paced, multitasking environment and should be taken into consideration in any undertaking aimed at improving hospital units' functioning. © 2015 John Wiley & Sons Ltd.

UNICOR: a species connectivity and corridor network simulator

Treesearch

E. L. Landguth; B. K. Hand; J. Glassy; S. A. Cushman; M. A. Sawaya

2012-01-01

We introduce UNIversal CORridor network simulator (UNICOR), a species connectivity and corridor identifi cation tool. UNICOR applies Dijkstra's shortest path algorithm to individual-based simulations. Outputs can be used to designate movement corridors, identify isolated populations, and prioritize conservation plans to promote species persistence. The key...

ENVIRONMENTAL ASSESSMENT FOR THE PROPOSED WITHDRAWAL OF PUBLIC LANDS WITHIN AND SURROUNDING THE CALIENTE RAIL CORRIDOR, NEVADA

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

DOE

2005-12-01

The purpose for agency action is to preclude surface entry and the location of new mining claims, subject to valid existing rights, within and surrounding the Caliente rail corridor as described in the Yucca Mountain FEIS (DOE 2002). This protective measure is needed to enhance the safe, efficient, and uninterrupted evaluation of land areas for potential rail alignments within the Caliente rail corridor. The evaluation will assist the DOE in determining, through the Rail Alignment environmental impact statement (EIS) process, whether to construct a branch rail line, and to provide support to the BLM in deciding whether or not tomore » reserve a ROW for the rail line under the Federal Land Policy and Management Act (FLPMA). The BLM participated as a cooperating agency in preparing this EA because it is the responsible land manager and BLM staff could contribute resource specific expertise.« less

Using collaborative tools for energy corridor planning.

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

Kuiper, J. A.; Cantwell, B.; Hlohowskyj, I.

2008-01-01

In November 2007, the Draft Programmatic Environmental Impact Statement on Designation of Energy Corridors on Federal Land in the Western 11 States was released. The draft proposes a network of 6055 miles of energy corridors on lands managed by seven different federal agencies. Determining the proposed locations of the corridors was a large collaborative effort among the agencies and included local, state, and federal land managers. To connect this geographically dispersed group of people, the project team employed a variety of approaches to communicate corridor siting issues, including sharing GIS layers and electronic maps, a downloadable GIS database and ArcReadermore » project, workshops, and Internet webcast teleconferences. This collaborative approach allowed difficult siting issues to be understood and discussed from many perspectives, which resulted in rapid and effective decision making. The result was a proposed corridor system that avoids many sensitive resources and protected lands while accommodating expected energy development.« less

46 CFR 92.10-30 - Dead end corridors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Dead end corridors. 92.10-30 Section 92.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-30 Dead end corridors. (a) Dead end corridors, or the...

46 CFR 92.10-30 - Dead end corridors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Dead end corridors. 92.10-30 Section 92.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-30 Dead end corridors. (a) Dead end corridors, or the...

46 CFR 92.10-30 - Dead end corridors.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Dead end corridors. 92.10-30 Section 92.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-30 Dead end corridors. (a) Dead end corridors, or the...

46 CFR 92.10-30 - Dead end corridors.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Dead end corridors. 92.10-30 Section 92.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-30 Dead end corridors. (a) Dead end corridors, or the...

46 CFR 92.10-30 - Dead end corridors.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Dead end corridors. 92.10-30 Section 92.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-30 Dead end corridors. (a) Dead end corridors, or the...

Agricultural conservation planning framework: 2. Classification of riparian buffer design-types with application to assess and map stream corridors

USDA-ARS?s Scientific Manuscript database

A watershed’s riparian corridor presents opportunities to stabilize streambanks, intercept runoff, and influence shallow groundwater with riparian buffers. This paper presents a system to classify these riparian opportunities and apply it towards riparian management planning in HUC12 watersheds. Hig...

Population dynamics of Microtus pennsylvanicus in corridor-linked patches

USGS Publications Warehouse

Coffman, C.J.; Nichols, J.D.; Pollock, K.H.

2001-01-01

Corridors have become a key issue in the discussion of conservation planning: however, few empirical data exist on the use of corridors and their effects on population dynamics. The objective of this replicated, population level, capture-re-capture experiment on meadow voles was to estimate and compare population characteristics of voles between (1) corridor-linked fragments, (2) isolated or non-linked fragments, and (3) unfragmented areas. We conducted two field experiments involving 22600 captures of 5700 individuals. In the first, the maintained corridor study, corridors were maintained at the time of fragmentation, and in the second, the constructed corridor study, we constructed corridors between patches that had been fragmented for some period of time. We applied multistate capture-recapture models with the robust design to estimate adult movement and survival rates, population size, temporal variation in population size, recruitment, and juvenile survival rates. Movement rates increased to a greater extent on constructed corridor-linked grids than on the unfragmented or non-linked fragmented grids between the pre- and post-treatment periods. We found significant differences in local survival on the treated (corridor-linked) grids compared to survival on the fragmented and unfragmented grids between the pre- and post-treatment periods. We found no clear pattern of treatment effects on population size or recruitment in either study. However, in both studies, we found that unfragmented grids were more stable than the fragmented grids based on lower temporal variability in population size. To our knowledge, this is the first experimental study demonstrating that corridors constructed between existing fragmented populations can indeed cause increases in movement and associated changes in demography, supporting the use of constructed corridors for this purpose in conservation biology.

46 CFR 190.10-30 - Dead end corridors.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Dead end corridors. 190.10-30 Section 190.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 190.10-30 Dead end corridors. (a) Dead end corridors, or the equivalent, more...

46 CFR 190.10-30 - Dead end corridors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Dead end corridors. 190.10-30 Section 190.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 190.10-30 Dead end corridors. (a) Dead end corridors, or the equivalent, more...

46 CFR 72.10-30 - Dead end corridors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 3 2010-10-01 2010-10-01 false Dead end corridors. 72.10-30 Section 72.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 72.10-30 Dead end corridors. (a) Dead end corridors, or the equivalent, more than 40...

46 CFR 72.10-30 - Dead end corridors.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 3 2013-10-01 2013-10-01 false Dead end corridors. 72.10-30 Section 72.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 72.10-30 Dead end corridors. (a) Dead end corridors, or the equivalent, more than 40...

46 CFR 190.10-30 - Dead end corridors.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Dead end corridors. 190.10-30 Section 190.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 190.10-30 Dead end corridors. (a) Dead end corridors, or the equivalent, more...

46 CFR 72.10-30 - Dead end corridors.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 3 2012-10-01 2012-10-01 false Dead end corridors. 72.10-30 Section 72.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 72.10-30 Dead end corridors. (a) Dead end corridors, or the equivalent, more than 40...

46 CFR 190.10-30 - Dead end corridors.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Dead end corridors. 190.10-30 Section 190.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 190.10-30 Dead end corridors. (a) Dead end corridors, or the equivalent, more...

46 CFR 72.10-30 - Dead end corridors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 3 2011-10-01 2011-10-01 false Dead end corridors. 72.10-30 Section 72.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 72.10-30 Dead end corridors. (a) Dead end corridors, or the equivalent, more than 40...

46 CFR 190.10-30 - Dead end corridors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Dead end corridors. 190.10-30 Section 190.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 190.10-30 Dead end corridors. (a) Dead end corridors, or the equivalent, more...

46 CFR 72.10-30 - Dead end corridors.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 3 2014-10-01 2014-10-01 false Dead end corridors. 72.10-30 Section 72.10-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 72.10-30 Dead end corridors. (a) Dead end corridors, or the equivalent, more than 40...

System architecture efforts in the Gary-Chicago-Milwaukee corridor

DOT National Transportation Integrated Search

1998-01-01

The Gary-Chicago-Milwaukee (GCM) Corridor is one of four Priority Corridors throughout the country. These corridors were selected for special federal transportation funding based on very specific transportation and environmental criteria. One o...

Corridors affect plants, animals, and their interactions in fragmented landscapes

PubMed Central

Tewksbury, Joshua J.; Levey, Douglas J.; Haddad, Nick M.; Sargent, Sarah; Orrock, John L.; Weldon, Aimee; Danielson, Brent J.; Brinkerhoff, Jory; Damschen, Ellen I.; Townsend, Patricia

2002-01-01

Among the most popular strategies for maintaining populations of both plants and animals in fragmented landscapes is to connect isolated patches with thin strips of habitat, called corridors. Corridors are thought to increase the exchange of individuals between habitat patches, promoting genetic exchange and reducing population fluctuations. Empirical studies addressing the effects of corridors have either been small in scale or have ignored confounding effects of increased habitat area created by the presence of a corridor. These methodological difficulties, coupled with a paucity of studies examining the effects of corridors on plants and plant–animal interactions, have sparked debate over the purported value of corridors in conservation planning. We report results of a large-scale experiment that directly address this debate. In eight large-scale experimental landscapes that control for patch area and test alternative mechanisms of corridor function, we demonstrate that corridors not only increase the exchange of animals between patches, but also facilitate two key plant–animal interactions: pollination and seed dispersal. Our results show that the beneficial effects of corridors extend beyond the area they add, and suggest that increased plant and animal movement through corridors will have positive impacts on plant populations and community interactions in fragmented landscapes. PMID:12239344

ENHANCED STREAM WATER QUALITY MODEL (QUAL2EU)

EPA Science Inventory

The enhanced stream water quality model QUAL2E and QUAL2E-UNCAS (37) permits simulation of several water quality constituents in a branching stream system using a finite difference solution to the one-dimensional advective-dispersive mass transport and reaction equation. The con...

Evolution of the Quadrantid meteor stream

NASA Technical Reports Server (NTRS)

Jones, James; Jones, William

1992-01-01

According to previous orbital calculations, the last close approach of the Quadrantid stream with Jupiter occurred 3200 years ago at which time the parent comet of the stream may have been captured into its present short-period orbit. If this is the case the stream may only be a few thousand years old. We have modeled the evolution of the stream to determine if such a short time scale is consistent with the observed features of the Quadrantid/ delta- Aquarid/Arietid/Ursid complex. A detailed modeling of a stream consisting of 500 test particles released 4000 yr ago and which included the effects of the gravitational perturbations of 6 planets as well as the likely spread in the initial orbital elements resulting from the ejection of the grains from the comet was carried out. Our calculations indicate that an intense shower should be seen a few days before the Quadrantid shower, and that, 4000 yr is too short a period for the branch corresponding to the D-Arietid branch to appear. We have considered the quasi-constants of motion 1/a and J, the Tisserand quantity, and find that the Ursids and the D-Arietids are unlikely to be members of the complex, and that, the complex is probably be less than 4000 yr old.

Comprehensive highway corridor planning with sustainability indicators.

DOT National Transportation Integrated Search

2011-10-01

"The Maryland State Highway Administration (SHA) has initiated major planning efforts to improve transportation : efficiency, safety, and sustainability on critical highway corridors through its Comprehensive Highway Corridor : (CHC) program. This pr...

Comprehensive highway corridor planning with sustainability indicators.

DOT National Transportation Integrated Search

2013-04-01

The Maryland State Highway Administration (SHA) has initiated major planning efforts to improve transportation : efficiency, safety, and sustainability on critical highway corridors through its Comprehensive Highway Corridor : (CHC) program. This pro...

Designing large-scale conservation corridors for pattern and process.

PubMed

Rouget, Mathieu; Cowling, Richard M; Lombard, Amanda T; Knight, Andrew T; Kerley, Graham I H

2006-04-01

A major challenge for conservation assessments is to identify priority areas that incorporate biological patterns and processes. Because large-scale processes are mostly oriented along environmental gradients, we propose to accommodate them by designing regional-scale corridors to capture these gradients. Based on systematic conservation planning principles such as representation and persistence, we identified large tracts of untransformed land (i.e., conservation corridors) for conservation that would achieve biodiversity targets for pattern and process in the Subtropical Thicket Biome of South Africa. We combined least-cost path analysis with a target-driven algorithm to identify the best option for capturing key environmental gradients while considering biodiversity targets and conservation opportunities and constraints. We identified seven conservation corridors on the basis of subtropical thicket representation, habitat transformation and degradation, wildlife suitability, irreplaceability of vegetation types, protected area networks, and future land-use pressures. These conservation corridors covered 21.1% of the planning region (ranging from 600 to 5200 km2) and successfully achieved targets for biological processes and to a lesser extent for vegetation types. The corridors we identified are intended to promote the persistence of ecological processes (gradients and fixed processes) and fulfill half of the biodiversity pattern target. We compared the conservation corridors with a simplified corridor design consisting of a fixed-width buffer along major rivers. Conservation corridors outperformed river buffers in seven out of eight criteria. Our corridor design can provide a tool for quantifying trade-offs between various criteria (biodiversity pattern and process, implementation constraints and opportunities). A land-use management model was developed to facilitate implementation of conservation actions within these corridors.

A coupled surface-water and ground-water flow model (MODBRANCH) for simulation of stream-aquifer interaction

USGS Publications Warehouse

Swain, Eric D.; Wexler, Eliezer J.

1996-01-01

Ground-water and surface-water flow models traditionally have been developed separately, with interaction between subsurface flow and streamflow either not simulated at all or accounted for by simple formulations. In areas with dynamic and hydraulically well-connected ground-water and surface-water systems, stream-aquifer interaction should be simulated using deterministic responses of both systems coupled at the stream-aquifer interface. Accordingly, a new coupled ground-water and surface-water model was developed by combining the U.S. Geological Survey models MODFLOW and BRANCH; the interfacing code is referred to as MODBRANCH. MODFLOW is the widely used modular three-dimensional, finite-difference ground-water model, and BRANCH is a one-dimensional numerical model commonly used to simulate unsteady flow in open- channel networks. MODFLOW was originally written with the River package, which calculates leakage between the aquifer and stream, assuming that the stream's stage remains constant during one model stress period. A simple streamflow routing model has been added to MODFLOW, but is limited to steady flow in rectangular, prismatic channels. To overcome these limitations, the BRANCH model, which simulates unsteady, nonuniform flow by solving the St. Venant equations, was restructured and incorporated into MODFLOW. Terms that describe leakage between stream and aquifer as a function of streambed conductance and differences in aquifer and stream stage were added to the continuity equation in BRANCH. Thus, leakage between the aquifer and stream can be calculated separately in each model, or leakages calculated in BRANCH can be used in MODFLOW. Total mass in the coupled models is accounted for and conserved. The BRANCH model calculates new stream stages for each time interval in a transient simulation based on upstream boundary conditions, stream properties, and initial estimates of aquifer heads. Next, aquifer heads are calculated in MODFLOW based on stream

Multimodal corridor and capacity analysis manual. Final report

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

NONE

1998-12-31

This report presents the results of research carried out under NCHRP Project 8-31, Long-Term Availability of Multimodal Corridor Capacity. The report is presented as a manual on multimodal corridor and capacity analysis. Because transportation-system and corridor capacity for freight and passengers is critical for meeting current and future transportation demand, this manual will provide much needed assistance to a wide range of practitioners, particularly those engaged in performance analysis, capacity management, needs studies, systems planning, and corridor development planning--including major investment studies. It provides information regarding capacity analysis approaches for highways, rail, pipelines, and waterways and presents available options formore » enhancing corridor capacity and performance through various strategies such as new capacity development, freeing up unused capacity, or control of travel demand. Evaluation methods for these options are included.« less

76 FR 34139 - Northeast Corridor Safety Committee; Meeting Postponement

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-10

.... 2] Northeast Corridor Safety Committee; Meeting Postponement AGENCY: Federal Railroad Administration... announced the first meeting of the Northeast Corridor Safety Committee, a Federal Advisory Committee... future date. DATES: The meeting of the Northeast Corridor Safety Committee scheduled to commence on...

Low-quality habitat corridors as movement conduits for two butterfly species.

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

Haddad, Nick, M.; Tewksbury, Joshua, J.

2005-01-01

Haddad, Nick, M, and Joshua J. Tewksbury. Low-quality habitat corridors as movement conduits for two butterfly species. Ecol. Apps. 15(1):250-257. Abstract. Corridors are a primary conservation tool to increase connectivity, promote individual movement, and increase gene flow among populations in fragmented landscapes. The establishment of effective conservation corridors will depend on constructing or pre-serving connecting habitat that attracts dispersing individuals. Yet, it remains unclear whether corridors must necessarily be composed of high-quality habitat to be effective and promote dispersal and gene flow. We address this issue with two mobile, open-habitat butterfly species, Junonia coenia HuÈbner and Euptoieta claudia Cramer. Usingmore » experimental landscapes created explicitly to examine the effects of corridors on dispersal rates, we show that open-habitat corridors can serve as dispersal conduits even when corridors do not support resident butterfly populations. Both butterfly species were rare near forest edges and equally rare in narrow corridors, yet both species dispersed more often between patches connected by these corridors than between isolated patches. At least for species that can traverse corridors within a generation, corridor habitat may be lower in quality than larger patches and still increase dispersal and gene flow. For these species, abundance surveys may not accurately represent the conservation value of corridors.« less

Response variables for evaluation of the effectiveness of conservation corridors.

PubMed

Gregory, Andrew J; Beier, Paul

2014-06-01

Many studies have evaluated effectiveness of corridors by measuring species presence in and movement through small structural corridors. However, few studies have assessed whether these response variables are adequate for assessing whether the conservation goals of the corridors have been achieved or considered the costs or lag times involved in measuring the response variables. We examined 4 response variables-presence of the focal species in the corridor, interpatch movement via the corridor, gene flow, and patch occupancy--with respect to 3 criteria--relevance to conservation goals, lag time (fewest generations at which a positive response to the corridor might be evident with a particular variable), and the cost of a study when applying a particular variable. The presence variable had the least relevance to conservation goals, no lag time advantage compared with interpatch movement, and only a moderate cost advantage over interpatch movement or gene flow. Movement of individual animals between patches was the most appropriate response variable for a corridor intended to provide seasonal migration, but it was not an appropriate response variable for corridor dwellers, and for passage species it was only moderately relevant to the goals of gene flow, demographic rescue, and recolonization. Response variables related to gene flow provided a good trade-off among cost, relevance to conservation goals, and lag time. Nonetheless, the lag time of 10-20 generations means that evaluation of conservation corridors cannot occur until a few decades after a corridor has been established. Response variables related to occupancy were most relevant to conservation goals, but the lag time and costs to detect corridor effects on occupancy were much greater than the lag time and costs to detect corridor effects on gene flow. © 2014 Society for Conservation Biology.

Delaware's transportation agenda in the northeast corridor.

DOT National Transportation Integrated Search

2009-10-01

The fractionated governance structure of the entire Northeast Corridor (Warren 2009) is also : evidenced within the Baltimore-to-Philadelphia portion, which contains the entire extent of : Delawares claim to the corridor. Though comprising only a ...

I-95 Corridor Crash Data Reporting Methods

DOT National Transportation Integrated Search

2010-06-01

Access to timely and accurate crash data is essential to improving safety and efficiency on the I-95 Corridor's transportation network. Crash data are used throughout the corridor by law enforcement, departments of transportation, licensing agencies ...

Alternative Fuels Data Center: West Virginia CNG Corridor Now Open

Science.gov Websites

West Virginia CNG Corridor Now Open to someone by E-mail Share Alternative Fuels Data Center: West Virginia CNG Corridor Now Open on Facebook Tweet about Alternative Fuels Data Center: West Virginia CNG Corridor Now Open on Twitter Bookmark Alternative Fuels Data Center: West Virginia CNG Corridor Now Open on

76 FR 72029 - Multistate Corridor Operations and Management Program

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-21

... in the FHWA Multistate Corridor Operations and Management Program as authorized in 23 U.S.C. 511... Multistate Corridor Operations and Management Program as authorized in 23 U.S.C. 511. This notice clarifies... DEPARTMENT OF TRANSPORTATION Federal Highway Administration Multistate Corridor Operations and...

Silicon Valley Smart Corridor : final evaluation report

DOT National Transportation Integrated Search

2003-08-01

This document summarizes the findings from the evaluation of the integrated freeway, arterial, and incident management system known as the Silicon Valley Smart Corridor (SVSC). Centered along the Highway 17/Interstate 880 corridor in San Jose, Califo...

Evaluation of the effect of buccal corridor size on smile attractiveness.

PubMed

Oshagh, Morteza; Zarif, Najafi H; Bahramnia, F

2010-01-01

an attractive smile helps people feel more self-confident and look younger. One of the more controversial aspects of smile attractiveness pertains to buccal corridor size. There is no previous study by those with artistic knowledge that has assessed the asthetic considerations of buccal corridor size. The purpose of this study was to observe whether the size of buccal corridors has an impact on smile attractiveness evaluated by lay people, dental students, and art students. colored post-treatment photograph with posed smiles of two subjects (one male, one female) were selected. The maxillary posterior dentitions were digitally altered to produce different buccal corridor sizes: narrow (28% buccal corridor), medium-narrow (22% buccal corridor), medium-broad (10% buccal corridor), and broad (2% buccal corridor). The 5 images of each subject were paired into 11 possible combinations and presented to three group: art students, dental students, and lay people, who compared the two images in each pair of smile attractiveness. The statistical test used were Wilcoxon signed rank and Mann-Whitney test. minimal and excessive buccal corridors were the least attractive when judged by three groups. All groups preferred smaller buccal corridors for the male subject and larger buccal corridors for the female subject. No significant judging differences were found between male and female judges from among art and dental students. minimal or excessive buccal corridor should be included in the problem list during orthodontic diagnosis and treatment planning.

Missouri River freight corridor assessment & development plan.

DOT National Transportation Integrated Search

2011-09-01

The purpose of the Missouri River Freight Corridor Development effort is to redevelop the river as a freight corridor with logical market nodes and reliable service that supports a sustainable market and logistics system. Four focus areas have been i...

43 CFR 2802.11 - How does BLM designate corridors?

Code of Federal Regulations, 2013 CFR

2013-10-01

... air, water, soil, fish, wildlife, and vegetation; (3) Physical effects and constraints on corridor... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false How does BLM designate corridors? 2802.11... POLICY MANAGEMENT ACT Lands Available for FLPMA Grants § 2802.11 How does BLM designate corridors? (a...

43 CFR 2802.11 - How does BLM designate corridors?

Code of Federal Regulations, 2012 CFR

2012-10-01

... air, water, soil, fish, wildlife, and vegetation; (3) Physical effects and constraints on corridor... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false How does BLM designate corridors? 2802.11... POLICY MANAGEMENT ACT Lands Available for FLPMA Grants § 2802.11 How does BLM designate corridors? (a...

43 CFR 2802.11 - How does BLM designate corridors?

Code of Federal Regulations, 2011 CFR

2011-10-01

... air, water, soil, fish, wildlife, and vegetation; (3) Physical effects and constraints on corridor... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false How does BLM designate corridors? 2802.11... POLICY MANAGEMENT ACT Lands Available for FLPMA Grants § 2802.11 How does BLM designate corridors? (a...

Evaluating landscape options for corridor restoration between giant panda reserves.

PubMed

Wang, Fang; McShea, William J; Wang, Dajun; Li, Sheng; Zhao, Qing; Wang, Hao; Lu, Zhi

2014-01-01

The establishment of corridors can offset the negative effects of habitat fragmentation by connecting isolated habitat patches. However, the practical value of corridor planning is minimal if corridor identification is not based on reliable quantitative information about species-environment relationships. An example of this need for quantitative information is planning for giant panda conservation. Although the species has been the focus of intense conservation efforts for decades, most corridor projects remain hypothetical due to the lack of reliable quantitative researches at an appropriate spatial scale. In this paper, we evaluated a framework for giant panda forest corridor planning. We linked our field survey data with satellite imagery, and conducted species occupancy modelling to examine the habitat use of giant panda within the potential corridor area. We then conducted least-cost and circuit models to identify potential paths of dispersal across the landscape, and compared the predicted cost under current conditions and alternative conservation management options considered during corridor planning. We found that due to giant panda's association with areas of low elevation and flat terrain, human infrastructures in the same area have resulted in corridor fragmentation. We then identified areas with high potential to function as movement corridors, and our analysis of alternative conservation scenarios showed that both forest/bamboo restoration and automobile tunnel construction would significantly improve the effectiveness of corridor, while residence relocation would not significantly improve corridor effectiveness in comparison with the current condition. The framework has general value in any conservation activities that anticipate improving habitat connectivity in human modified landscapes. Specifically, our study suggested that, in this landscape, automobile tunnels are the best means to remove current barriers to giant panda movements caused by

Evaluating Landscape Options for Corridor Restoration between Giant Panda Reserves

PubMed Central

Wang, Fang; McShea, William J.; Wang, Dajun; Li, Sheng; Zhao, Qing; Wang, Hao; Lu, Zhi

2014-01-01

The establishment of corridors can offset the negative effects of habitat fragmentation by connecting isolated habitat patches. However, the practical value of corridor planning is minimal if corridor identification is not based on reliable quantitative information about species-environment relationships. An example of this need for quantitative information is planning for giant panda conservation. Although the species has been the focus of intense conservation efforts for decades, most corridor projects remain hypothetical due to the lack of reliable quantitative researches at an appropriate spatial scale. In this paper, we evaluated a framework for giant panda forest corridor planning. We linked our field survey data with satellite imagery, and conducted species occupancy modelling to examine the habitat use of giant panda within the potential corridor area. We then conducted least-cost and circuit models to identify potential paths of dispersal across the landscape, and compared the predicted cost under current conditions and alternative conservation management options considered during corridor planning. We found that due to giant panda's association with areas of low elevation and flat terrain, human infrastructures in the same area have resulted in corridor fragmentation. We then identified areas with high potential to function as movement corridors, and our analysis of alternative conservation scenarios showed that both forest/bamboo restoration and automobile tunnel construction would significantly improve the effectiveness of corridor, while residence relocation would not significantly improve corridor effectiveness in comparison with the current condition. The framework has general value in any conservation activities that anticipate improving habitat connectivity in human modified landscapes. Specifically, our study suggested that, in this landscape, automobile tunnels are the best means to remove current barriers to giant panda movements caused by

An experimental test of whether habitat corridors affect pollen transfer.

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

Townsend, Patricia A.; Levey, Douglas J.

Abstract. Negative effects of habitat fragmentation are thought to be diminished when habitat patches are joined by a corridor. A key assumption is that corridors facilitate exchange rates of organisms between otherwise isolated patches. If the organisms are pollinators, corridors may be important for maintaining genetically viable populations of the plants that they pollinate. We tested the hypothesis that corridors increase the movement of insect pollinators into patches of habitat and thereby increase pollen transfer for two species of plants, one pollinated by butterflies (Lantana camara) and the other by bees and wasps (Rudbeckia hirta). We worked in an experimentalmore » landscape consisting of 40 greater than or equal to 1-ha patches of early-successional habitat in a matrix of forest. Within each of eight experimental units, two patches were connected by a corridor (150 X 25 m), and three were not. Patch shape varied to control for the area added by the presence of a corridor. Differences in patch shape also allowed us to test alternative hypotheses of how corridors might function. The Traditional Corridor Hypothesis posits that corridors increase immigration and emigration by functioning as movement conduits between patches. The Drift Fence Hypothesis posits that corridors function by ‘‘capturing’’ organisms dispersing through the matrix, redirecting them into associated habitat patches. Using fluorescent powder to track pollen, we found that pollen transfer by butterflies between patches connected by a corridor was significantly higher than between unconnected patches (all values mean plus or minus 1 SE: 59% plus or minus 9.2% vs. 25% plus or minus 5.2% of flowers receiving pollen). Likewise, pollen transfer by bees and wasps was significantly higher between connected patches than between unconnected patches (30% plus or minus 4.2% vs. 14.5% plus or minus 2.2%). These results support the Traditional Corridor Hypothesis. There was little support

Groundwater availability in the Crouch Branch and McQueen Branch aquifers, Chesterfield County, South Carolina, 1900-2012

USGS Publications Warehouse

Campbell, Bruce G.; Landmeyer, James E.

2014-01-01

, totaled about 1,117 square miles. Major types of data used as input to the model included groundwater levels, groundwater-use data, and hydrostratigraphic data, along with estimates and measurements of stream base flows made specifically for this study. The groundwater-flow model was calibrated to groundwater-level and stream base-flow conditions from 1900 to 2012 using 39 stress periods. The model was calibrated with an automated parameter-estimation approach using the computer program PEST, and the model used regularized inversion and pilot points. The groundwater-flow model was calibrated using field data that included groundwater levels that had been collected between 1940 and 2012 from 239 wells and base-flow measurements from 44 locations distributed within the study area. To better understand recharge and inter-aquifer interactions, seven wells were equipped with continuous groundwater-level recording equipment during the course of the study, between 2008 and 2012. These water levels were included in the model calibration process. The observed groundwater levels were compared to the simulated ones, and acceptable calibration fits were achieved. Root mean square error for the simulated groundwater levels compared to all observed groundwater levels was 9.3 feet for the Crouch Branch aquifer and 8.6 feet for the McQueen Branch aquifer. The calibrated groundwater-flow model was then used to calculate groundwater budgets for the entire study area and for two sub-areas. The sub-areas are the Alligator Rural Water and Sewer Company well field near McBee, South Carolina, and the Carolina Sandhills National Wildlife Refuge acquisition boundary area. For the overall model area, recharge rates vary from 56 to 1,679 million gallons per day (Mgal/d) with a mean of 737 Mgal/d over the simulation period (1900–2012). The simulated water budget for the streams and rivers varies from 653 to 1,127 Mgal/d with a mean of 944 Mgal/d. The simulated “storage-in term” ranges from 0

Impact of landscape disturbance on the quality of terrestrial sediment carbon in temperate streams

NASA Astrophysics Data System (ADS)

Fox, James F.; Ford, William I.

2016-09-01

Recent studies have shown the super saturation of fluvial networks with respect to carbon dioxide, and the concept that the high carbon dioxide is at least partially the result of turnover of sediment organic carbon that ranges in age from years to millennia. Currently, there is a need for more highly resolved studies at stream and river scales that enable estimates of terrestrial carbon turnover within fluvial networks. Our objective was to develop a new isotope-based metric to estimate the quality of sediment organic carbon delivered to temperate streams and to use the new metric to estimate carbon quality across landscape disturbance gradients. Carbon quality is defined to be consistent with in-stream turnover and our metric is used to measure the labile or recalcitrant nature of the terrestrial-derived carbon within streams. Our hypothesis was that intensively-disturbed landscapes would tend to produce low quality carbon because deep, recalcitrant soil carbon would be eroded and transported to the fluvial system while moderately disturbed or undisturbed landscapes would tend to produce higher quality carbon from well-developed surface soils and litter. The hypothesis was tested by applying the new carbon quality metric to 15 temperate streams with a wide range of landscape disturbance levels. We find that our hypothesis premised on an indirect relationship between the extent of landscape disturbance and the quality of sediment carbon in streams holds true for moderate and high disturbances but not for un-disturbed forests. We explain the results based on the connectivity, or dis-connectivity, between terrestrial carbon sources and pathways for sediment transport. While pathways are typically un-limited for disturbed landscapes, the un-disturbed forests have dis-connectivity between labile carbon of the forest floor and the stream corridor. Only in the case when trees fell into the stream corridor due to severe ice storms did the quality of sediment carbon

The genetic admixture in Tibetan-Yi Corridor.

PubMed

Yao, Hong-Bing; Tang, Senwei; Yao, Xiaotian; Yeh, Hui-Yuan; Zhang, Wanhu; Xie, Zhiyan; Du, Qiajun; Ma, Liying; Wei, Shuoyun; Gong, Xue; Zhang, Zilong; Li, Quanfang; Xu, Bingying; Zhang, Hu-Qin; Chen, Gang; Wang, Chuan-Chao

2017-11-01

The Tibetan-Yi Corridor located on the eastern edge of Tibetan Plateau is suggested to be the key region for the origin and diversification of Tibeto-Burman speaking populations and the main route of the peopling of the Plateau. However, the genetic history of the populations in the Corridor is far from clear due to limited sampling in the northern part of the Corridor. We collected blood samples from 10 Tibetan and 10 Han Chinese individuals from Gansu province and genotyped about 600,000 genome-wide single nucleotide polymorphisms (SNPs). Our data revealed that the populations in the Corridor are all admixed on a genetic cline of deriving ancestry from Tibetans on the Plateau and surrounding lowland East Asians. The Tibetan and Han Chinese groups in the north of the Plateau show significant evidence of low-level West Eurasian admixture that could be probably traced back to 600∼900 years ago. We conclude that there have been huge population migrations from surrounding lowland onto the Tibetan Plateau via the Tibetan-Yi Corridor since the initial formation of Tibetans probably in Neolithic Time, which leads to the current genetic structure of Tibeto-Burman speaking populations. © 2017 Wiley Periodicals, Inc.

Chemical quality of surface water in the West Branch Susquehanna River basin, Pennsylvania

USGS Publications Warehouse

McCarren, Edward F.

1964-01-01

The West Branch Susquehanna River is 228 miles long and drains 6,913 square miles of mountainous area in central Pennsylvania. Much of this area is forestcovered wilderness, part of which is reserved as State game land. Wild animals, such as deer, bear, turkey and grouse, are sheltered there, and many streams contain trout and other game fish. This helps to make the region one of the best hunting and fishing areas in Pennsylvania. The Congress has approved Federal funds for the construction of several reservoirs to prevent flooding of the main river and several of its tributaries. Water stored behind the dams will not be withdrawn below a minimum level designated as conservation pools. These pools will be available for recreation. Several headwater streams, such as Clearfield, Moshannon, and at times Sinnemahoning Creek, that carry drainage from coal mines are acid and contain high concentrations of dissolved solids, especially sulfates. These streams acidify the West Branch Susquehanna River downstream as far as Jersey Shore. One of the most influential tributaries affecting the quality of the West Branch Susquehanna River after they merge is Bald Eagle Creek. Bald Eagle Creek enters the main river downstream from Lock Haven which is approximately 100 river miles from the river's source. Because of its alkaline properties, water of Bald Eagle Creek can neutralize acidic water. Many streams draining small areas and several draining large areas such as Pine Creek, Lycoming Creek, and Loyalsock Creek are clear nearly neutral water low in dissolved solids whose pH is about 7.0 most of the time. These streams have a diluting and neutralizing effect on the quality of the West Branch Susquehanna River, so that from Williamsport downstream the river water is rarely acid, and for most of the time it is of good chemical quality.

77 FR 3326 - Northeast Corridor Safety Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-23

.... 3] Northeast Corridor Safety Committee; Notice of Meeting AGENCY: Federal Railroad Administration (FRA), Department of Transportation (DOT). ACTION: Announcement of Northeast Corridor Safety Committee Meeting. SUMMARY: FRA announced the first meeting of the Northeast Corridor Safety Committee, a Federal...

76 FR 32391 - Northeast Corridor Safety Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-06

.... 1] Northeast Corridor Safety Committee; Notice of Meeting AGENCY: Federal Railroad Administration (FRA), Department of Transportation (DOT). ACTION: Announcement of the Northeast Corridor Safety Committee Meeting. SUMMARY: FRA announces the first meeting of the Northeast Corridor Safety Committee, a...

Integrated corridor management analysis, modeling, and simulation for the I-15 corridor in San Diego, California post-deployment assessment report.

DOT National Transportation Integrated Search

2016-12-01

The U.S. Department of Transportation Integrated Corridor Management (ICM) Initiative aims to advance the state of the practice in transportation corridor operations to manage congestion. Through the deployment of ICM at the two selected Demonstratio...

Response of imperiled Okaloosa darters to stream restoration

USGS Publications Warehouse

Reeves, David B.; Tate, William B.; Jelks, Howard L.; Jordan, Frank

2016-01-01

The Okaloosa Darter Etheostoma okaloosae is a small percid endemic to six stream drainages in northwestern Florida. The U.S. Fish and Wildlife Service listed Okaloosa Darters as endangered in 1973 and downlisted them to threatened in 2011 because of habitat improvements and increasing abundance across much of their geographic range. Delisting is possible if remaining recovery criteria are met, including restoration of degraded stream reaches. Impounded reaches of Anderson Branch, Mill Creek, and Toms Creek were restored by removing impediments to water flow, draining impoundments, and reconstructing stream reaches. Restorations of Anderson Branch and Mill Creek were designed to rehabilitate populations of Okaloosa Darters without significantly affecting popular recreational activities at these locations. Restorations were evaluated from 2007 to 2013 by comparing counts of Okaloosa Darters and the composition of microhabitats in restored and nearby undisturbed reference sites. Okaloosa Darters were absent from degraded stream reaches at the beginning of the study, but they rapidly colonized once restorations were completed. Counts of Okaloosa Darters in reference and restoration sites in Anderson Branch were similar by the end of the study, whereas counts in restoration sites were significantly lower than nearby reference sites in Mill and Toms creeks. Restoration sites tended to have lower coverage of sand and root and higher coverage of macrophytes. As riparian vegetation surrounding restoration sites matures to a closed canopy that reduces excessive growth of macrophytes, stream microhabitats and numbers of darters will probably become similar to reference sites. Restoration of degraded stream sites increased abundance and distribution of Okaloosa Darters and reconnected formerly isolated upstream and downstream populations. These projects demonstrated that restoration is a useful conservation tool for imperiled fishes such as Okaloosa Darters and can be

Boulder Creek: A stream ecosystem in an urban landscape

USGS Publications Warehouse

Verplanck, Philip L.; Murphy, Sheila F.; Birkeland, Peter W.; Pitlick,; Barber, Larry B.; Schmidt, Travis S.; Raynolds, Robert G.H.

2008-01-01

The Boulder Creek Watershed, within the Front Range region of Colorado, is typical of many western watersheds because it is composed of a high-gradient upper reach mostly fed by snowmelt, a substantial change in gradient at the range front, and an urban corridor within the lower gradient section. A stream ecosystem within an urban landscape not only can provide water for municipal, industrial, and agricultural needs, but also can be utilized for recreation, esthetic enjoyment, and wastewater disposal. The purpose of this 26 km bicycle field trip is to explore the hydrology and geochemistry of Boulder and South Boulder Creeks and to discuss topics including flood frequency and hazards, aqueous geochemistry of the watershed, and potential impacts of invasive species and emerging contaminants on stream ecology.

Economic corridor of industrial development in Indonesia

NASA Astrophysics Data System (ADS)

Berawi, M. A.; Miraj, P.; Sidqi, H.

2017-12-01

Indonesia as an archipelago country categorize its regional development into six corridors from Sumatra, Java, Kalimantan, Sulawesi, Bali-Nusa Tenggara and Papua-Maluku. Currently, industrial development becomes one of the highest contributing factors to the national economic growth. However, each region in the nation experience inequality of development mainly related to the infrastructure sector. Thus, the research aims to develop a sustainable economic corridor by considering the characteristics and its potential. The research uses a qualitative approach through a desk study, benchmarking and in-depth interview. Location Quotient is used for the method of the analysis tool. The results show each characteristic of every corridor in the country. Sumatera as national plantation and processing industry corridor, Java as cyber technology innovation and services center, Kalimantan as national energy reserves and processing, Sulawesi as national aquaculture and processing industry, Bali - Nusa Tenggara as national eco-tourism center, and Papua - Maluku as national ore mining and processing.

Analysis of Potential Energy Corridors Proposed by the Western Electricity Coordinating Council

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

Kuiper, James A.; Cantwell, Brian J.; Hlava, Kevin J.

2014-02-24

This report, Analysis of Potential Energy Corridors Proposed by the Western Electricity Coordinating Council (WECC), was prepared by the Environmental Science Division of Argonne National Laboratory (Argonne). The intent of WECC’s work was to identify planning-level energy corridors that the Department of Energy (DOE) and its affiliates could study in greater detail. Argonne was tasked by DOE to analyze the WECC Proposed Energy Corridors in five topic areas for use in reviewing and revising existing corridors, as well as designating additional energy corridors in the 11 western states. In compliance with Section 368 of the Energy Policy Act of 2005more » (EPAct), the Secretaries of Energy, Agriculture, and the Interior (Secretaries) published a Programmatic Environmental Impact Statement in 2008 to address the proposed designation of energy transport corridors on federal lands in the 11 western states. Subsequently, Records of Decision designating the corridors were issued in 2009 by the Bureau of Land Management (BLM) and the U.S. Forest Service (USFS). The 2012 settlement of a lawsuit, brought by The Wilderness Society and others against the United States, which identified environmental concerns for many of the corridors requires, among other things, periodic reviews of the corridors to assess the need for revisions, deletions, or additions. A 2013 Presidential Memorandum requires the Secretaries to undertake a continuing effort to identify and designate energy corridors. The WECC Proposed Energy Corridors and their analyses in this report provide key information for reviewing and revising existing corridors, as well as designating additional energy corridors in the 11 western states. Load centers and generation hubs identified in the WECC analysis, particularly as they reflect renewable energy development, would be useful in reviewing and potentially updating the designated Section 368 corridor network. Argonne used Geographic Information System (GIS

76 FR 3695 - Environmental Impact Statement: Interstate 64 Corridor, Virginia

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-20

...: Interstate 64 Corridor, Virginia AGENCY: Federal Highway Administration (FHWA), DOT. ACTION: Notice of Intent... Transportation for potential transportation improvements along the Interstate 64 corridor in Virginia. FOR... improvements along the Interstate 64 corridor in Virginia. The approximate limits of the study are Interstate...

Grazed Riparian Management and Stream Channel Response in Southeastern Minnesota (USA) Streams

NASA Astrophysics Data System (ADS)

Magner, Joseph A.; Vondracek, Bruce; Brooks, Kenneth N.

2008-09-01

The U.S. Department of Agriculture-Natural Resources Conservation Service has recommended domestic cattle grazing exclusion from riparian corridors for decades. This recommendation was based on a belief that domestic cattle grazing would typically destroy stream bank vegetation and in-channel habitat. Continuous grazing (CG) has caused adverse environmental damage, but along cohesive-sediment stream banks of disturbed catchments in southeastern Minnesota, short-duration grazing (SDG), a rotational grazing system, may offer a better riparian management practice than CG. Over 30 physical and biological metrics were gathered at 26 sites to evaluate differences between SDG, CG, and nongrazed sites (NG). Ordinations produced with nonmetric multidimensional scaling (NMS) indicated a gradient with a benthic macroinvertebrate index of biotic integrity (IBI) and riparian site management; low IBI scores associated with CG sites and higher IBI scores associated with NG sites. Nongrazed sites were associated with reduced soil compaction and higher bank stability, as measured by the Pfankuch stability index; whereas CG sites were associated with increased soil compaction and lower bank stability, SDG sites were intermediate. Bedrock geology influenced NMS results: sites with carbonate derived cobble were associated with more stable channels and higher IBI scores. Though current riparian grazing practices in southeastern Minnesota present pollution problems, short duration grazing could reduce sediment pollution if managed in an environmentally sustainable fashion that considers stream channel response.

Grazed riparian management and stream channel response in southeastern Minnesota (USA) streams

USGS Publications Warehouse

Magner, J.A.; Vondracek, B.; Brooks, K.N.

2008-01-01

The U.S. Department of Agriculture-Natural Resources Conservation Service has recommended domestic cattle grazing exclusion from riparian corridors for decades. This recommendation was based on a belief that domestic cattle grazing would typically destroy stream bank vegetation and in-channel habitat. Continuous grazing (CG) has caused adverse environmental damage, but along cohesive-sediment stream banks of disturbed catchments in southeastern Minnesota, short-duration grazing (SDG), a rotational grazing system, may offer a better riparian management practice than CG. Over 30 physical and biological metrics were gathered at 26 sites to evaluate differences between SDG, CG, and nongrazed sites (NG). Ordinations produced with nonmetric multidimensional scaling (NMS) indicated a gradient with a benthic macroinvertebrate index of biotic integrity (IBI) and riparian site management; low IBI scores associated with CG sites and higher IBI scores associated with NG sites. Nongrazed sites were associated with reduced soil compaction and higher bank stability, as measured by the Pfankuch stability index; whereas CG sites were associated with increased soil compaction and lower bank stability, SDG sites were intermediate. Bedrock geology influenced NMS results: sites with carbonate derived cobble were associated with more stable channels and higher IBI scores. Though current riparian grazing practices in southeastern Minnesota present pollution problems, short duration grazing could reduce sediment pollution if managed in an environmentally sustainable fashion that considers stream channel response. ?? 2008 Springer Science+Business Media, LLC.

Final report: Prototyping a combustion corridor

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

Rutland, Christopher J.; Leach, Joshua

2001-12-15

The Combustion Corridor is a concept in which researchers in combustion and thermal sciences have unimpeded access to large volumes of remote computational results. This will enable remote, collaborative analysis and visualization of state-of-the-art combustion science results. The Engine Research Center (ERC) at the University of Wisconsin - Madison partnered with Lawrence Berkeley National Laboratory, Argonne National Laboratory, Sandia National Laboratory, and several other universities to build and test the first stages of a combustion corridor. The ERC served two important functions in this partnership. First, we work extensively with combustion simulations so we were able to provide real worldmore » research data sets for testing the Corridor concepts. Second, the ERC was part of an extension of the high bandwidth based DOE National Laboratory connections to universities.« less

45 CFR 800.204 - Reinsurance, risk corridors, and risk adjustment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 45 Public Welfare 3 2013-10-01 2013-10-01 false Reinsurance, risk corridors, and risk adjustment... Adjustment § 800.204 Reinsurance, risk corridors, and risk adjustment. (a) Transitional reinsurance program... transitional reinsurance program for the individual market. (b) Temporary risk corridors program. An MSPP...

45 CFR 800.204 - Reinsurance, risk corridors, and risk adjustment.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 45 Public Welfare 3 2014-10-01 2014-10-01 false Reinsurance, risk corridors, and risk adjustment... Adjustment § 800.204 Reinsurance, risk corridors, and risk adjustment. (a) Transitional reinsurance program... transitional reinsurance program for the individual market. (b) Temporary risk corridors program. An MSPP...

Establishing freight corridors.

DOT National Transportation Integrated Search

2006-03-01

The NM DOT Research Bureau requested that the ATR Institute (ATRI) assist them in research which would identify the factors for establishing freight corridors for rail and truck across New Mexico; gain an understanding of multimodal planning for the ...

Corridor management and preservation in Texas : 2010 workshops

DOT National Transportation Integrated Search

2010-01-01

2007 RMC Project 05606 : Report 56061, Creating Partnerships with Local Communities to Manage and Preserve Corridors Basis for Workshop; 5606P1, Guidelines on Corridor Management and Preservation; 5606S, Summary Report. Workshop is an ...

ICMS concept of operations for a generic corridor

DOT National Transportation Integrated Search

2006-04-18

This Generic Concept of Operations for Integrated Corridor Management (ICM) has been developed as part of Phase 1 (Foundational Research) for the Federal Highway Administration and the Federal Transit Administration (FHWA/FTA) Integrated Corridor Man...

The role of corridors in conservation: Solution or bandwagon?

PubMed

Hobbs, R J

1992-11-01

Corridors are currently a major buzzword in conservation biology and landscape ecology. These linear landscape features may perform numerous functions, but it is their role in facilitating movement of fauna that has attracted much recent debate. The database supporting the idea of corridors acting as faunal conduits is remarkably small, and few studies have actually demonstrated that movement along corridors is important for any given species. Such data are very difficult to obtain, and conservation biologists are thus faced with the problem of whether to recommend the allocation of resources to corridors on the assumption that they may be important. Copyright © 1992. Published by Elsevier Ltd.

Integrated corridor management : implementation guide and lessons learned.

DOT National Transportation Integrated Search

2012-02-01

This implementation guide is intended for use by adopters of integrated corridor management (ICM) approaches and strategies to address congestion and travel time reliability issues within specific travel corridors. It introduces the topic of ICM and ...

Habitat corridors facilitate genetic resilience irrespective of species dispersal abilities or population sizes.

PubMed

Christie, Mark R; Knowles, L Lacey

2015-06-01

Corridors are frequently proposed to connect patches of habitat that have become isolated due to human-mediated alterations to the landscape. While it is understood that corridors can facilitate dispersal between patches, it remains unknown whether corridors can mitigate the negative genetic effects for entire communities modified by habitat fragmentation. These negative genetic effects, which include reduced genetic diversity, limit the potential for populations to respond to selective agents such as disease epidemics and global climate change. We provide clear evidence from a forward-time, agent-based model (ABM) that corridors can facilitate genetic resilience in fragmented habitats across a broad range of species dispersal abilities and population sizes. Our results demonstrate that even modest increases in corridor width decreased the genetic differentiation between patches and increased the genetic diversity and effective population size within patches. Furthermore, we document a trade-off between corridor quality and corridor design whereby populations connected by high-quality habitat (i.e., low corridor mortality) are more resilient to suboptimal corridor design (e.g., long and narrow corridors). The ABM also revealed that species interactions can play a greater role than corridor design in shaping the genetic responses of populations to corridors. These results demonstrate how corridors can provide long-term conservation benefits that extend beyond targeted taxa and scale up to entire communities irrespective of species dispersal abilities or population sizes.

Habitat corridors facilitate genetic resilience irrespective of species dispersal abilities or population sizes

PubMed Central

Christie, Mark R; Knowles, L Lacey

2015-01-01

Corridors are frequently proposed to connect patches of habitat that have become isolated due to human-mediated alterations to the landscape. While it is understood that corridors can facilitate dispersal between patches, it remains unknown whether corridors can mitigate the negative genetic effects for entire communities modified by habitat fragmentation. These negative genetic effects, which include reduced genetic diversity, limit the potential for populations to respond to selective agents such as disease epidemics and global climate change. We provide clear evidence from a forward-time, agent-based model (ABM) that corridors can facilitate genetic resilience in fragmented habitats across a broad range of species dispersal abilities and population sizes. Our results demonstrate that even modest increases in corridor width decreased the genetic differentiation between patches and increased the genetic diversity and effective population size within patches. Furthermore, we document a trade-off between corridor quality and corridor design whereby populations connected by high-quality habitat (i.e., low corridor mortality) are more resilient to suboptimal corridor design (e.g., long and narrow corridors). The ABM also revealed that species interactions can play a greater role than corridor design in shaping the genetic responses of populations to corridors. These results demonstrate how corridors can provide long-term conservation benefits that extend beyond targeted taxa and scale up to entire communities irrespective of species dispersal abilities or population sizes. PMID:26029259

Corridors and some ecological and evolutionary consequences of connectivity.

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

Orrock, John L

2004-07-01

Abstract - By connecting disjunct patches, corridors may offset the effects of fragmentation by promoting gene flow and population persistence. However, the ultimate effect of corridors on a focal species may hinge upon two considerations: how corridors may affect ecological interactions that impinge upon that species, and how corridors might affect the fixation of novel alleles that ultimately determine fitness and persistence. Using an experimental landscape, I show that corridor-mediated changes in patch shape change seed predation in connected and unconnected patches, and shift the behavior, abundance, and distribution of seed predators. Rodent seed predators removed more seeds in connectedmore » patches, arthropod seed predators removed more seeds in rectangular patches, and avian seed predation did not differ due to patch type. Rodent foraging was greater in the interior of connected patches because changes in patch shape influenced risk perceived by rodents while foraging. Ant communities were also affected by changes in patch shape caused by corridors, rather than corridor effects per se. The distribution and abundance of ants differed among edge-rich areas (corridors and wings), edges, and the patch interior. In rectangular patches, fire ants (Solenopsis spp.) had negative impacts on other ant species. By changing the activity of rodents, and the composition of ant communities, corridors may have important impacts on seeds. Bird-dispersed seeds may benefit from increased dispersal among connected patches, but connected patches also have greater predation risk. Using a simulation model, I demonstrate that gene flow between a stable population and a population that experiences local extinction or a reduction in size (e.g. due to natural or anthropogenic disturbance) can dramatically affect fixation of alleles in the stable population. Alone or in concert, frequent disturbance, high rates of movement, and low habitat quality make it more likely that

4. Corridor B. Perspective of west side as viewed from ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. Corridor B. Perspective of west side as viewed from roof of Building No. 9982. The flat-roof building that joins Corridor B is Building No. 9981, Receiving and Evacuation Building. - Madigan Hospital, Corridors & Ramps, Bounded by Wilson & McKinley Avenues & Garfield & Lincoln Streets, Tacoma, Pierce County, WA

Corridor Length and Patch Colonization by a Butterfly, Junonia coenia

Treesearch

Nick Haddad

2000-01-01

Corridors have been proposed to reduce isolation and increase population persistence in fragmented landscapes, yet little research has evaluated the types of landscapes in which corridors will be most effective. I tested the hypothesis that corridors increase patch colonization by a butterfly, Junonia coenia, regardless of the butterfly's...

Analysis of Florida Department of Transportation transit corridor program/projects : technical memorandum number one - review and summary of transit corridor plans

DOT National Transportation Integrated Search

2001-05-01

The purpose of this project was to undertake a consolidated comprehensive review of the Florida Department of Transportation Transit Corridor Program. Technical Memorandum Number One provides a summary of all transit corridor projects either under wa...

Integrated corridor management : analysis, modeling, and simulation for the U.S.-75 corridor in Dallas, Texas – post-deployment assessment report.

DOT National Transportation Integrated Search

2016-11-01

The U.S. Department of Transportation Integrated Corridor Management (ICM) Initiative aims to advance the state of the practice in transportation corridor operations to manage congestion. Through the deployment of ICM at the two selected Demonstratio...

Parametric entry corridors for lunar/Mars aerocapture missions

NASA Technical Reports Server (NTRS)

Ling, Lisa M.; Baseggio, Franco M.; Fuhry, Douglas P.

1991-01-01

Parametric atmospheric entry corridor data are presented for Earth and Mars aerocapture. Parameter ranges were dictated by the range of mission designs currently envisioned as possibilities for the Human Exploration Initiative (HEI). This data, while not providing a means for exhaustive evaluation of aerocapture performance, should prove to be a useful aid for preliminary mission design and evaluation. Entry corridors are expressed as ranges of allowable vacuum periapse altitude of the planetary approach hyperbolic orbit, with chart provided for conversion to an approximate flight path angle corridor at entry interface (125 km altitude). The corridor boundaries are defined by open-loop aerocapture trajectories which satisfy boundary constraints while utilizing the full aerodynamic control capability of the vehicle (i.e., full lift-up or full lift-down). Parameters examined were limited to those of greatest importance from an aerocapture performance standpoint, including the approach orbit hyperbolic excess velocity, the vehicle lift to drag ratio, maximum aerodynamic load factor limit, and the apoapse of the target orbit. The impact of the atmospheric density bias uncertainties are also included. The corridor data is presented in graphical format, and examples of the utilization of these graphs for mission design and evaluation are included.

Trade-offs and efficiencies in optimal budget-constrained multispecies corridor networks.

PubMed

Dilkina, Bistra; Houtman, Rachel; Gomes, Carla P; Montgomery, Claire A; McKelvey, Kevin S; Kendall, Katherine; Graves, Tabitha A; Bernstein, Richard; Schwartz, Michael K

2017-02-01

Conservation biologists recognize that a system of isolated protected areas will be necessary but insufficient to meet biodiversity objectives. Current approaches to connecting core conservation areas through corridors consider optimal corridor placement based on a single optimization goal: commonly, maximizing the movement for a target species across a network of protected areas. We show that designing corridors for single species based on purely ecological criteria leads to extremely expensive linkages that are suboptimal for multispecies connectivity objectives. Similarly, acquiring the least-expensive linkages leads to ecologically poor solutions. We developed algorithms for optimizing corridors for multispecies use given a specific budget. We applied our approach in western Montana to demonstrate how the solutions may be used to evaluate trade-offs in connectivity for 2 species with different habitat requirements, different core areas, and different conservation values under different budgets. We evaluated corridors that were optimal for each species individually and for both species jointly. Incorporating a budget constraint and jointly optimizing for both species resulted in corridors that were close to the individual species movement-potential optima but with substantial cost savings. Our approach produced corridors that were within 14% and 11% of the best possible corridor connectivity for grizzly bears (Ursus arctos) and wolverines (Gulo gulo), respectively, and saved 75% of the cost. Similarly, joint optimization under a combined budget resulted in improved connectivity for both species relative to splitting the budget in 2 to optimize for each species individually. Our results demonstrate economies of scale and complementarities conservation planners can achieve by optimizing corridor designs for financial costs and for multiple species connectivity jointly. We believe that our approach will facilitate corridor conservation by reducing acquisition costs

Trade-offs and efficiencies in optimal budget-constrained multispecies corridor networks

USGS Publications Warehouse

Dilkina, Bistra; Houtman, Rachel; Gomes, Carla P.; Montgomery, Claire A.; McKelvey, Kevin; Kendall, Katherine; Graves, Tabitha A.; Bernstein, Richard; Schwartz, Michael K.

2017-01-01

Conservation biologists recognize that a system of isolated protected areas will be necessary but insufficient to meet biodiversity objectives. Current approaches to connecting core conservation areas through corridors consider optimal corridor placement based on a single optimization goal: commonly, maximizing the movement for a target species across a network of protected areas. We show that designing corridors for single species based on purely ecological criteria leads to extremely expensive linkages that are suboptimal for multispecies connectivity objectives. Similarly, acquiring the least-expensive linkages leads to ecologically poor solutions. We developed algorithms for optimizing corridors for multispecies use given a specific budget. We applied our approach in western Montana to demonstrate how the solutions may be used to evaluate trade-offs in connectivity for 2 species with different habitat requirements, different core areas, and different conservation values under different budgets. We evaluated corridors that were optimal for each species individually and for both species jointly. Incorporating a budget constraint and jointly optimizing for both species resulted in corridors that were close to the individual species movement-potential optima but with substantial cost savings. Our approach produced corridors that were within 14% and 11% of the best possible corridor connectivity for grizzly bears (Ursus arctos) and wolverines (Gulo gulo), respectively, and saved 75% of the cost. Similarly, joint optimization under a combined budget resulted in improved connectivity for both species relative to splitting the budget in 2 to optimize for each species individually. Our results demonstrate economies of scale and complementarities conservation planners can achieve by optimizing corridor designs for financial costs and for multiple species connectivity jointly. We believe that our approach will facilitate corridor conservation by reducing acquisition costs

Habitat corridors function as both drift fences and movement conduits for dispersing flies.

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

Fried, Joanna H.; Levey Douglas J.; Hogsette, Jerome A.

2005-03-30

Abstract Corridors connect otherwise isolated habitat patches and can direct movement of animals among such patches. In eight experimental landscapes, we tested two hypotheses of how corridors might affect dispersal behavior. The Traditional Corridor hypothesis posits that animals preferentially leave patches via corridors, following them into adjacent patches. The Drift Fence hypothesis posits that animals dispersing through matrix habitat are diverted into patches with corridors because they follow corridors when encountered. House flies (Musca domestica L.), a species that prefers the habitat of our patches and corridors, were released in a central patch (100•100 m) and recaptured in peripheral patchesmore » that were or were not connected by a corridor. Flies were captured more frequently in connected than unconnected patches, thereby supporting the Traditional Corridor hypothesis. The Drift Fence hypothesis was also supported, as flies were captured more frequently in unconnected patches with blind (dead end) corridors than in unconnected patches of equal area without blind corridors. A second experiment tested whether these results might be dependent on the type of patch-matrix boundary encountered by dispersing flies and whether edge-following behavior might be the mechanism underlying the observed corridor effect in the first experiment. We recorded dispersal patterns of flies released along forest edges with dense undergrowth in the forest (‘‘closed’’ edges) and along edges with little forest understory (‘‘open’’ edges). Flies were less likely to cross and more likely to follow closed edges than open edges, indicating that when patch and corridor edges are pronounced, edge-following behavior of flies may direct them along corridors into connected patches. Because edges in the first experiment were open, these results also suggest that corridor effects for flies in that experiment would have been even stronger if the edges around the

Identifying transit corridors for elephant using a long time-series

NASA Astrophysics Data System (ADS)

Pittiglio, Claudia; Skidmore, Andrew K.; van Gils, Hein A. M. J.; Prins, Herbert H. T.

2012-02-01

The role of corridors in mitigating the effects of landscape fragmentation on biodiversity is controversial. Recent studies have highlighted the need for new approaches in corridor design using long-term datasets. We present a method to identify transit corridors for elephant at a population scale over a large area and an extended period of time using long-term aerial surveys. We investigated environmental and anthropogenic factors directly and indirectly related to the wet versus dry season distribution of elephant and its transit corridors. Four environmental variables predicted the presence of elephant at the landscape scale in both seasons: distance from permanent water, protected areas and settlements and vegetation structure. Path analysis revealed that altitude and monthly average NDVI, and distance from temporary water had a significant indirect effect on elephant distribution at local scale in dry and wet seasons respectively. Five transit corridors connecting Tarangire National Park and the northern as well as south-eastern wet season dispersal areas were identified and matched the wildlife migration routes described in the 1960s. The corridors are stable over the decades, providing landscape connectivity for elephant. Our approach yielded insights how advanced spatial analysis can be integrated with biological data available from long-term datasets to identify actual transit corridors and predictors of species distribution.

View looking south along the main corridor on the third ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View looking south along the main corridor on the third floor of the south wing. The openings along the top of the corridor walls allowed for the movement of air and light between the corridor and the resident rooms. - U. S. Naval Asylum, Biddle Hall, Gray's Ferry Avenue, Philadelphia, Philadelphia County, PA

HANFORD SITE RIVER CORRIDOR CLEANUP

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

BAZZELL, K.D.

2006-02-01

In 2005, the US Department of Energy (DOE) launched the third generation of closure contracts, including the River Corridor Closure (RCC) Contract at Hanford. Over the past decade, significant progress has been made on cleaning up the river shore that bordes Hanford. However, the most important cleanup challenges lie ahead. In March 2005, DOE awarded the Hanford River Corridor Closure Contract to Washington Closure Hanford (WCH), a limited liability company owned by Washington Group International, Bechtel National and CH2M HILL. It is a single-purpose company whose goal is to safely and efficiently accelerate cleanup in the 544 km{sup 2} Hanfordmore » river corridor and reduce or eliminate future obligations to DOE for maintaining long-term stewardship over the site. The RCC Contract is a cost-plus-incentive-fee closure contract, which incentivizes the contractor to reduce cost and accelerate the schedule. At $1.9 billion and seven years, WCH has accelerated cleaning up Hanford's river corridor significantly compared to the $3.2 billion and 10 years originally estimated by the US Army Corps of Engineers. Predictable funding is one of the key features of the new contract, with funding set by contract at $183 million in fiscal year (FY) 2006 and peaking at $387 million in FY2012. Another feature of the contract allows for Washington Closure to perform up to 40% of the value of the contract and subcontract the balance. One of the major challenges in the next few years will be to identify and qualify sufficient subcontractors to meet the goal.« less

Laurentide glacial landscapes: the role of ice streams

USGS Publications Warehouse

Patterson, C.J.

1998-01-01

Glacial landforms of the North American prairie can be divided into two suites that result from different styles of ice flow: 1) a lowland suite of level-to-streamlined till consistent with formation beneath ice streams, and 2) an upland and lobe-margin suite of thick, hummocky till and glacial thrust blocks consistent with formation at ice-stream and ice-lobe margins. Southern Laurentide ice lobes hypothetically functioned as outlets of ice streams. Broad branching lowlands bounded by escarpments mark the stable positions of the ice streams that fed the lobes. If the lobes and ice streams were similar to modern ice streams, their fast flow was facilitated by high subglacial water pressure. Favorable geology and topography in the midcontinent encouraged nonuniform ice flow and controlled the location of ice streams and outlet lobes.

Energy Futures Synthesis for West-Wide Section 368 Energy Corridors

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

O'Neill, Barbara L.; Gagne, Douglas A.; Cook, Jeffrey J.

To comply with Section 368(a) of the Energy Policy Act of 2005 (EPAct), the U.S. Bureau of Land Management (BLM) and the U.S. Forest Service designated 6,000 miles of energy corridors on public and national forest lands in the western United States in 2009. The corridors, commonly referred to as 'West-wide' or 'Section 368' energy corridors, are intended as preferred locations for future siting of electric transmission and distribution lines and for oil, gas, and hydrogen pipelines. In response to a lawsuit filed by several organizations over the corridor designations, the BLM, Forest Service, and the U.S. Department of Energymore » entered into a Settlement Agreement, directing the formation of the Section 368 Interagency Workgroup to periodically review the energy corridors on a regional basis. In conducting the reviews, the Workgroup identifies new, relevant, existing, publicly available information to make recommendations for revisions, deletions, and additions to the Section 368 energy corridors. This report synthesizes information in available contemporary transmission, pipeline, and energy future studies to inform the regional reviews by providing a snapshot of what the western energy and transmission system will look like generally 10-15 years in the future. After an overview of the western grid implications, the analysis narrows to Region 2 and Region 3 of the BLM Section 368 energy corridors and focuses on the implications of potential developments in the oil, natural gas, and electricity markets in Colorado, New Mexico, Utah, and portions of Arizona and Nevada that could inform the current regional review. This analysis will help inform the Workgroup on potential development within existing corridors and the need for new corridors that have not yet been designated.« less

Particulate organic contributions from forests and streams: debris isn't so bad

Treesearch

C. Andrew Dolloff; Jackson R. Webster

2000-01-01

It is clear that the input of "debris" from terrestrial plants falling into streams is one of the most significant processes occurring at the interface of terrestrial and stream ecosystems. Organic matter?leaves, twigs, branches, and whole trees?provides energy, nutrients, and structure to streams flowing through forests. A host of vertebrate and invertebrate...

An Ecological Study on the Introduction of the Banded Sculpin Into a Coal Flyash Impacted Stream

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

Carrico, B.A.; Ryon, M.G.

1996-02-01

A number of banded sculpins [Cottus carolinae (Gill)] were obtained from a population in a reference stream, marked with subcutaneous acrylic paint injections, and introduced into McCoy Branch, a small second-order stream located on the Oak Ridge Reservation in eastern Tennessee, which was inhabited by only a few banded sculpins prior to the study. McCoy Branch had received deposits of coal ash slurry for a prolonged period, however, there were some indications of recovery in the macroinvertebrate community due to improvements in water quality. Stream habitat characteristics and water chemistry parameters were monitored in McCoy Branch and a reference streammore » for a three-year period. Feeding patterns and reproductive activities of the banded sculpins were also monitored during the study. Sculpin population parameters including density, condition factor, and young-of-year (YOY) abundance and survival were studied. The results of the study show that the introduced fish have survived and appear to be in good condition. The sculpins have maintained a density of approximately 0.12 fish per square meter of stream, a figure similar to that found in other headwater streams located in the region. Colonization rates and sculpin densities in McCoy Branch were lower than expected, perhaps due to physical habitat degradation and reduced macroinvertebrate abundance. Evidence of sculpin reproduction in McCoy Branch was seen in the presence of gravid female sculpins (1994 and 1995) and YOY fish (1993 through 1995 year classes). This study indicates that McCoy Branch continues to recover from past perturbations to the point where it can now support a viable population of banded sculpins.« less

Spirit of place of Merdeka corridor in Selatpanjang City

NASA Astrophysics Data System (ADS)

Aldy, Pedia; Dharma, S. Mira

2018-03-01

Historical city area was developing by an accumulation of developmental stages which influenced by various factors. The factors are political, economic, social, cultural, and modernization. The research will discuss the spirit of place of Merdeka corridor in Selatpanjang city, Meranti Islands. The purpose is to identify the spirit of place of Merdeka corridor and to find out the tourism concept by characters that support urban tourism in Selatpanjang city. The research method used is qualitative research method with the rationalistic paradigm. Based on cultural history, physical building, and spatial pattern, Merdeka corridor has unique characteristic, and it persists if compared by another in Selatpanjang city. However, damage of corridor, physical changes, and functions can slowly happen due to modernization and cannot avoid.

Effects of vegetation, corridor width and regional land use on early successional birds on powerline corridors.

PubMed

Askins, Robert A; Folsom-O'Keefe, Corrine M; Hardy, Margaret C

2012-01-01

Powerline rights-of-way (ROWs) often provide habitat for early successional bird species that have suffered long-term population declines in eastern North America. To determine how the abundance of shrubland birds varies with habitat within ROW corridors and with land use patterns surrounding corridors, we ran Poisson regression models on data from 93 plots on ROWs and compared regression coefficients. We also determined nest success rates on a 1-km stretch of ROW. Seven species of shrubland birds were common in powerline corridors. However, the nest success rates for prairie warbler (Dendroica discolor) and field sparrow (Spizella pusilla) were <21%, which is too low to compensate for estimated annual mortality. Some shrubland bird species were more abundant on narrower ROWs or at sites with lower vegetation or particular types of vegetation, indicating that vegetation management could be refined to favor species of high conservation priority. Also, several species were more abundant in ROWs traversing unfragmented forest than those near residential areas or farmland, indicating that corridors in heavily forested regions may provide better habitat for these species. In the area where we monitored nests, brood parasitism by brown-headed cowbirds (Molothrus ater) occurred more frequently close to a residential area. Although ROWs support dense populations of shrubland birds, those in more heavily developed landscapes may constitute sink habitat. ROWs in extensive forests may contribute more to sustaining populations of early successional birds, and thus may be the best targets for habitat management.

Effects of Vegetation, Corridor Width and Regional Land Use on Early Successional Birds on Powerline Corridors

PubMed Central

Askins, Robert A.; Folsom-O'Keefe, Corrine M.; Hardy, Margaret C.

2012-01-01

Powerline rights-of-way (ROWs) often provide habitat for early successional bird species that have suffered long-term population declines in eastern North America. To determine how the abundance of shrubland birds varies with habitat within ROW corridors and with land use patterns surrounding corridors, we ran Poisson regression models on data from 93 plots on ROWs and compared regression coefficients. We also determined nest success rates on a 1-km stretch of ROW. Seven species of shrubland birds were common in powerline corridors. However, the nest success rates for prairie warbler (Dendroica discolor) and field sparrow (Spizella pusilla) were <21%, which is too low to compensate for estimated annual mortality. Some shrubland bird species were more abundant on narrower ROWs or at sites with lower vegetation or particular types of vegetation, indicating that vegetation management could be refined to favor species of high conservation priority. Also, several species were more abundant in ROWs traversing unfragmented forest than those near residential areas or farmland, indicating that corridors in heavily forested regions may provide better habitat for these species. In the area where we monitored nests, brood parasitism by brown-headed cowbirds (Molothrus ater) occurred more frequently close to a residential area. Although ROWs support dense populations of shrubland birds, those in more heavily developed landscapes may constitute sink habitat. ROWs in extensive forests may contribute more to sustaining populations of early successional birds, and thus may be the best targets for habitat management. PMID:22363660

43 CFR 2802.11 - How does BLM designate corridors?

Code of Federal Regulations, 2014 CFR

2014-10-01

... activities located within the proposed right-of-way corridor; (7) Social and economic impacts of the right-of...) Transportation and utility corridor studies previously developed by user groups; and (9) Engineering and...

Comprehensive highway corridor planning with sustainability indicators : [research summary].

DOT National Transportation Integrated Search

2013-04-01

The Maryland State Highway Administration (SHA) has initiated major planning : efforts to improve transportation efficiency, safety and sustainability on critical : highway corridors through its Comprehensive Highway Corridor (CHC) program. : It is i...

Carbon pools along headwater streams with differing valley geometry in Rocky Mountain National Park, Colorado (Abstract)

Treesearch

Kathleen A. Dwire; Ellen E. Wohl; Nicholas A. Sutfin; Roberto A. Bazan; Lina Polvi-Pilgrim

2012-01-01

Headwaters are known to be important in the global carbon cycle, yet few studies have investigated carbon (C) pools along stream-riparian corridors. To better understand the spatial distribution of C storage in headwater fluvial networks, we estimated above- and below-ground C pools in 100-m-long reaches in six different valley types in Rocky Mountain National Park,...

Salamander occupancy in headwater stream networks

USGS Publications Warehouse

Grant, E.H.C.; Green, L.E.; Lowe, W.H.

2009-01-01

1. Stream ecosystems exhibit a highly consistent dendritic geometry in which linear habitat units intersect to create a hierarchical network of connected branches. 2. Ecological and life history traits of species living in streams, such as the potential for overland movement, may interact with this architecture to shape patterns of occupancy and response to disturbance. Specifically, large-scale habitat alteration that fragments stream networks and reduces connectivity may reduce the probability a stream is occupied by sensitive species, such as stream salamanders. 3. We collected habitat occupancy data on four species of stream salamanders in first-order (i.e. headwater) streams in undeveloped and urbanised regions of the eastern U.S.A. We then used an information-theoretic approach to test alternative models of salamander occupancy based on a priori predictions of the effects of network configuration, region and salamander life history. 4. Across all four species, we found that streams connected to other first-order streams had higher occupancy than those flowing directly into larger streams and rivers. For three of the four species, occupancy was lower in the urbanised region than in the undeveloped region. 5. These results demonstrate that the spatial configuration of stream networks within protected areas affects the occurrences of stream salamander species. We strongly encourage preservation of network connections between first-order streams in conservation planning and management decisions that may affect stream species.

Soil quality and the solar corridor crop system

USDA-ARS?s Scientific Manuscript database

The solar corridor crop system (SCCS) is designed for improved crop productivity based on highly efficient use of solar radiation by integrating row crops with drilled or solid-seeded crops in broad strips (corridors) that also facilitate establishment of cover crops for year-round soil cover. The S...

Soil Quality and the Solar Corridor Crop System

USDA-ARS?s Scientific Manuscript database

The solar corridor crop system (SCCS) is designed for improved crop productivity based on highly efficient use of solar radiation by integrating row crops with drilled or solid-seeded crops in broad strips (corridors) that also facilitate establishment of cover crops for year-round soil cover. The S...

Continental hydrosystem modelling: the concept of nested stream-aquifer interfaces

NASA Astrophysics Data System (ADS)

Flipo, N.; Mouhri, A.; Labarthe, B.; Biancamaria, S.; Rivière, A.; Weill, P.

2014-08-01

Coupled hydrological-hydrogeological models, emphasising the importance of the stream-aquifer interface, are more and more used in hydrological sciences for pluri-disciplinary studies aiming at investigating environmental issues. Based on an extensive literature review, stream-aquifer interfaces are described at five different scales: local [10 cm-~10 m], intermediate [~10 m-~1 km], watershed [10 km2-~1000 km2], regional [10 000 km2-~1 M km2] and continental scales [>10 M km2]. This led us to develop the concept of nested stream-aquifer interfaces, which extends the well-known vision of nested groundwater pathways towards the surface, where the mixing of low frequency processes and high frequency processes coupled with the complexity of geomorphological features and heterogeneities creates hydrological spiralling. This conceptual framework allows the identification of a hierarchical order of the multi-scale control factors of stream-aquifer hydrological exchanges, from the larger scale to the finer scale. The hyporheic corridor, which couples the river to its 3-D hyporheic zone, is then identified as the key component for scaling hydrological processes occurring at the interface. The identification of the hyporheic corridor as the support of the hydrological processes scaling is an important step for the development of regional studies, which is one of the main concerns for water practitioners and resources managers. In a second part, the modelling of the stream-aquifer interface at various scales is investigated with the help of the conductance model. Although the usage of the temperature as a tracer of the flow is a robust method for the assessment of stream-aquifer exchanges at the local scale, there is a crucial need to develop innovative methodologies for assessing stream-aquifer exchanges at the regional scale. After formulating the conductance model at the regional and intermediate scales, we address this challenging issue with the development of an

The Fornax-Leo-Sculptor stream revisited

NASA Technical Reports Server (NTRS)

Majewski, Steven R.

1994-01-01

Lynden-Bell first demonstrated that the satellites of the Milky Way appear situated along two great 'streams' in the sky: the 'Magellanic stream' and the 'Fornax-Leo-Sculptor (FLS) stream.' Further exploration of the three-dimensional distribution of Galactic satellites reveals that the recently discovered Sextans and Phoenix dwarf spheroidal galaxies also lie near the plane defined by the FLS galaxies, and therefore strengthens the evidence in favor of the FLS stream. Moreover, a specific group of globular clusters -- those exhibiting the reddest horizontal branches (HBs) among those identified as 'young halo' by Zinn -- appear to populate the FLS stream. As previously demonstrated by Zinn, the spatial distribution of old halo globulars appears to be flattened toward the Galactic plane, and therefore the old halo clusters are typically anti-correlated to the nearly orthogonal FLS stream. A scenario is postulated wherein the Galactic satellites of the FLS stream and the red HB, young halo globular clusters share a common origin in the accretion of a formerly larger, parent satellite galaxy or Searle & Zinn 'fragment.'

Final report : Dallas Integrated Corridor Management (ICM) Demonstration Project.

DOT National Transportation Integrated Search

2015-08-01

The Dallas Area Rapid Transit (DART) is leading the US-75 Integrated Corridor Management (ICM) Demonstration Project for the Dallas region. Coordinated corridor operations and management is predicated on being able to share transportation information...

Test report : Dallas Integrated Corridor Management (ICM) demonstration project.

DOT National Transportation Integrated Search

2015-05-01

The Dallas Area Rapid Transit (DART) is leading the US 75 Integrated Corridor Management (ICM) Demonstration Project for the Dallas region. Coordinated corridor operations and management is predicated on being able to share transportation information...

Training plan : Dallas Integrated Corridor Management (ICM) demonstration project.

DOT National Transportation Integrated Search

2013-01-01

The Dallas Area Rapid Transit (DART) is leading the US 75 Integrated Corridor Management (ICM) Demonstration Project for the Dallas region. Coordinated corridor operations and management is predicated on being able to share transportation information...

China Pakistan Economic Corridor (CPEC): Challenges and the Way Forward

DTIC Science & Technology

2017-06-01

ECONOMIC CORRIDOR (CPEC): CHALLENGES AND THE WAY FORWARD by Muzaffar Hussain June 2017 Thesis Advisor: Robert E. Looney Second Reader...DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE CHINA PAKISTAN ECONOMIC CORRIDOR (CPEC): CHALLENGES AND THE WAY FORWARD 5. FUNDING NUMBERS...is unlimited. 12b. DISTRIBUTION CODE 13. ABSTRACT The China-Pakistan Economic Corridor (CPEC)—the latest venture in a history of bilateral economic

METHODS FOR MULTI-SPATIAL SCALE CHARACTERIZATION OF RIPARIAN CORRIDORS

EPA Science Inventory

This paper describes the application of aerial photography and GIS technology to develop flexible and transferable methods for multi-spatial scale characterization and analysis of riparian corridors. Relationships between structural attributes of riparian corridors and indicator...

90-94 ITS Intercity Corridor Study - Strategic Deployment Plan

DOT National Transportation Integrated Search

1996-12-01

PUBLIC-PRIVATE PARTNERSHIP, COMMERCIAL VEHICLES OPERATIONS OR CVO : THE IH 90/94 ITS INTERCITY CORRIDOR STRATEGIC DEPLOYMENT PLAN IS AN APPROACH FOR IMPLEMENTING INTELLIGENT TRANSPORTATION SYSTEMS (ITS) IN THE IH 90/94 CORRIDORS THAT TRAVERSE THE ...

Mortality patterns among residents in Louisiana's industrial corridor, USA, 1970–99

PubMed Central

Tsai, S; Cardarelli, K; Wendt, J; Fraser, A

2004-01-01

Background: Because of the high concentration of oil refining and petrochemical facilities, the industrial area of the lower Mississippi River of South Louisiana has been termed the Industrial Corridor and has frequently been referred to as the "Cancer Corridor". Aims: To quantitatively assess the "Cancer Corridor" controversy based on mortality data available in the public domain, and to identify potential contributing factors to the observed differences in mortality. Methods: Age adjusted mortality rates were calculated for white and non-white males and females in the Industrial Corridor, Louisiana, and the United States for the time periods 1970–79, 1980–89, and 1990–99. Results: All-cause mortality and all cancer combined for white males in the Industrial Corridor were significantly lower than the corresponding Louisiana population while Louisiana had significantly higher rates than the US population for all three time periods. Cancer of the lung was consistently higher in the Industrial Corridor region relative to national rates but lower than or similar to Louisiana. Non-respiratory disease and cerebrovascular disease mortality for white males in the Industrial Corridor were consistently lower than either Louisiana or the USA. However, mortality due to diabetes and heart disease, particularly during the 1990s, was significantly higher in the Industrial Corridor and Louisiana when compared to the USA. Similar mortality patterns were observed for white females. The mortality for non-white males and females in the Industrial Corridor was generally similar to the corresponding populations in Louisiana. There were no consistent patterns for all cancer mortality combined. Stomach cancer was increased among non-whites in both the Industrial Corridor and Louisiana when compared to the corresponding US data. Mortality from diabetes and heart disease among non-whites was significantly higher in the Industrial Corridor and Louisiana than in the USA. Conclusions

Sustainable Strategies for the Dynamic Equilibrium of the Urban Stream, Cheonggyecheon

NASA Astrophysics Data System (ADS)

Seo, D.; Kwon, Y.

2018-04-01

Cheonggyecheon, which had been transformed into a 14-lane urban highway and a large underground sewer system, was finally converted back to an urban stream again. Its transformation has been praised as a successful example of urban downtown regeneration and beautification. It is, however, obvious that there have not been prudent ecological considerations since the project’s principal goals were to provide public recreational use and achieve maximum flood control capacity via the use of embankments. For a healthier and sustainable stream environment, Cheonggyecheon should be ecologically re-restored again, based on a dynamic equilibrium model. It must primarily establish a corridor of vegetation, an aquatic transitional zone, and install constructed wetlands nearby which support the water source. The upper streams of Cheonggyecheon should be further restored and supply natural waters. Furthermore, there ultimately needs to be de-channelization for hydrological sustainability. This would vary from merely increasing the sinuosity to thoroughly reconstruct a naturalized stream. Complete dynamic equilibrium of Cheonggyecheon can be accomplished through more fundamental sustainable strategies.

Rivers and streams: Ecosystem dynamics and integrating paradigms

USGS Publications Warehouse

Cummins, K.W.; Wilzbach, M.A.

2008-01-01

Full understanding of running waters requires an ecosystem perspective, which encompasses the physical and chemical setting in interaction with dependent biological communities. Several conceptual models or paradigms of river and stream ecosystems that capture critical components of lotic ecosystems have been developed, including the ‘river continuum concept’, to describe fluxes of matter and energy within the stream or river channel together with exchanges between the channel and its terrestrial setting. A complete ecosystem perspective includes consideration of hierarchical spatial scales in a temporal context. Flow of energy in lotic ecosystems is driven by two alternative energy sources: sunlight regulating in-stream photosynthesis and plant litter derived from the stream-side riparian corridor or floodplain. Energy transfers within the ecosystem pass through micro- and macroproducers (algae and vascular hydrophytes) and micro- and macroconsumers (microorganisms, invertebrates, and vertebrates). Material fluxes encompass the cycling of key nutrients, such as nitrogen and phosphorus, and the transport, storage, and metabolism of dissolved (DOM) and particulate (POM) organic matter (OM). Growth of lotic periphyton (algae and associated microbes, microzoans, and detritus) and coarse (CPOM) and fine (FPOM) particulate organic matter constitute the food resources of nonpredaceous running-water invertebrates (e.g., shredders that consume CPOM and collectors that feed on FPOM and associated microbes of both).

South Carolina southeast high speed rail corridor improvement study

DOT National Transportation Integrated Search

2001-02-01

The Southeast Rail Corridor was originally designated as a high-speed corridor in Section 1010 of the Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991. More specifically, it involved the high-speed grade-crossing improvement program o...

Corridors restore animal-mediated pollination in fragmented tropical forest landscapes

PubMed Central

Kormann, Urs; Scherber, Christoph; Tscharntke, Teja; Klein, Nadja; Larbig, Manuel; Valente, Jonathon J.; Hadley, Adam S.; Betts, Matthew G.

2016-01-01

Tropical biodiversity and associated ecosystem functions have become heavily eroded through habitat loss. Animal-mediated pollination is required in more than 94% of higher tropical plant species and 75% of the world's leading food crops, but it remains unclear if corridors avert deforestation-driven pollination breakdown in fragmented tropical landscapes. Here, we used manipulative resource experiments and field observations to show that corridors functionally connect neotropical forest fragments for forest-associated hummingbirds and increase pollen transfer. Further, corridors boosted forest-associated pollinator availability in fragments by 14.3 times compared with unconnected equivalents, increasing overall pollination success. Plants in patches without corridors showed pollination rates equal to bagged control flowers, indicating pollination failure in isolated fragments. This indicates, for the first time, that corridors benefit tropical forest ecosystems beyond boosting local species richness, by functionally connecting mutualistic network partners. We conclude that small-scale adjustments to landscape configuration safeguard native pollinators and associated pollination services in tropical forest landscapes. PMID:26817765

Corridors and olfactory predator cues affect small mammal behavior.

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

Brinkerhoff, Robert Jory; Haddad, Nick M.; Orrock, John L.

2005-03-30

Abstract The behavior of prey individuals is influenced by a variety of factors including, but not limited to, habitat configuration, risk of predation, and availability of resources, and these habitat-dependent factors may have interactive effects. We studied the responses of mice to an increase in perceived predation risk in a patchy environment to understand how habitat corridors might affect interactions among species in a fragmented landscape. We used a replicated experiment to investigate corridor-mediated prey responses to predator cues in a network of open habitat patches surrounded by a matrix of planted pine forest. Some of the patches were connectedmore » by corridors. We used mark–recapture techniques and foraging trays to monitor the movement, behavior, and abundance of small mammals. Predation threat was manipulated in one-half of the replicates by applying an olfactory predator cue. Corridors synchronized small mammal foraging activity among connected patches. Foraging also was inhibited in the presence of an olfactory predator cue but apparently increased in adjacent connected patches. Small mammal abundance did not change as a result of the predator manipulation and was not influenced by the presence of corridors. This study is among the 1st to indicate combined effects of landscape configuration and predation risk on prey behavior. These changes in prey behavior may, in turn, have cascading effects on community dynamics where corridors and differential predation risk influence movement and patch use.« less

Extended endoscopic transsphenoidal approach infrachiasmatic corridor.

PubMed

Ceylan, Savas; Anik, Ihsan; Koc, Kenan; Cabuk, Burak

2015-01-01

An extended endoscopic transsphenoidal approach is required for skull base lesions extending to the suprasellar area. Inferior approach using the infrachiasmatic corridor allows access to the lesions through the tumor growth that is favorable for the extended transsphenoidal approaches. Infrachiasmatic corridor is a safer route for the inferior approaches that is made up by basal arachnoid membrane and Liliequist's membrane with its leaves (diencephalic and mesencephalic leaf). This area extends from the optic canal and tuberculum sella to the corpus mamillare. We performed extended endoscopic approach using the infrachiasmatic corridor in 52 cases, including tuberculum sella meningiomas (n:23), craniopharyngiomas (n:16), suprasellar Rathke's cleft cyst (n:6), pituitary adenoma (n:2), fibrous dysplasia (n:1), infundibular granulosa cell tumor (n:2), and epidermoid tumor (n:2). Total resection was achieved in 17 of 23 (74%) with tuberculum sellae meningioma using infrachiasmatic approach. Twenty patients presented with visual disorders and 14 of them improved. There were two postoperative cerebrospinal fluid (CSF) leakages and one transient diabetes insipidus and one permanent diabetes insipidus. Sixteen patients were operated on by the infrachiasmatic approach for craniopharyngiomas. Improvement was reached in seven of eight patients presented with visual disorders. Complete tumor resection was performed in 10 of 16 cases and cyst aspiration in 4 cases, and there were remnants in two cases. Postoperative CSF leakage was seen in two patients. Infrachiasmatic corridor provides an easier and safer inferior route for the removal of middle midline skull base lesions in selected cases.

78 FR 77550 - Integrated Corridor Management Deployment Planning Grants

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-23

... of this program is to promote the integrated management and operations of the transportation system... DEPARTMENT OF TRANSPORTATION Federal Highway Administration Integrated Corridor Management... the Integrated Corridor Management Deployment Planning Grants. The purpose of this notice was to...

Use of Individual Flight Corridors to Avoid Vortex Wakes

NASA Technical Reports Server (NTRS)

Rossow, Vernon J.

2001-01-01

Vortex wakes of aircraft pose a hazard to following aircraft until the energetic parts of their flow fields have decayed to a harmless level. It is suggested here that in-trail spacings between aircraft can be significantly and safely reduced by designing an individual, vortex-free flight corridor for each aircraft. Because each aircraft will then have its own flight corridor, which is free of vortex wakes while in use by the assigned aircraft, the time intervals between aircraft operations can be safely reduced to the order of seconds. The productivity of airports can then be substantially increased. How large the offset distances between operational corridors need to be to have them vortex free, and how airports need to be changed to accommodate an individual flight-corridor process for landing and takeoff operations, are explored. Estimates are then made of the productivity of an individual flight-corridor system as a function of the in-trail time interval between operations for various values of wake decay time, runway width, and the velocity of a sidewind. The results confirm the need for short time intervals between aircraft operations if smaller offset distances and increased productivity are to be achieved.

Relations of water-quality constituent concentrations to surrogate measurements in the lower Platte River corridor, Nebraska, 2007 through 2011

USGS Publications Warehouse

Schaepe, Nathaniel J.; Soenksen, Philip J.; Rus, David L.

2014-01-01

The lower Platte River, Nebraska, provides drinking water, irrigation water, and in-stream flows for recreation, wildlife habitat, and vital habitats for several threatened and endangered species. The U.S. Geological Survey (USGS), in cooperation with the Lower Platte River Corridor Alliance (LPRCA) developed site-specific regression models for water-quality constituents at four sites (Shell Creek near Columbus, Nebraska [USGS site 06795500]; Elkhorn River at Waterloo, Nebr. [USGS site 06800500]; Salt Creek near Ashland, Nebr. [USGS site 06805000]; and Platte River at Louisville, Nebr. [USGS site 06805500]) in the lower Platte River corridor. The models were developed by relating continuously monitored water-quality properties (surrogate measurements) to discrete water-quality samples. These models enable existing web-based software to provide near-real-time estimates of stream-specific constituent concentrations to support natural resources management decisions. Since 2007, USGS, in cooperation with the LPRCA, has continuously monitored four water-quality properties seasonally within the lower Platte River corridor: specific conductance, water temperature, dissolved oxygen, and turbidity. During 2007 through 2011, the USGS and the Nebraska Department of Environmental Quality collected and analyzed discrete water-quality samples for nutrients, major ions, pesticides, suspended sediment, and bacteria. These datasets were used to develop the regression models. This report documents the collection of these various water-quality datasets and the development of the site-specific regression models. Regression models were developed for all four monitored sites. Constituent models for Shell Creek included nitrate plus nitrite, total phosphorus, orthophosphate, atrazine, acetochlor, suspended sediment, and Escherichia coli (E. coli) bacteria. Regression models that were developed for the Elkhorn River included nitrate plus nitrite, total Kjeldahl nitrogen, total phosphorus

78 FR 7477 - Multistate Corridor Operations and Management Program

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-01

... in the Multistate Corridor Operations and Management Program authorized by the Safe, Accountable... projects to improve multimodal transportation system management and operations. This notice seeks... Multistate Corridor Operations and Management (MCOM) programs and projects. The purpose of these investments...

Effectiveness of a regional corridor in connecting two Florida black bear populations.

PubMed

Dixon, Jeremy D; Oli, Madan K; Wooten, Michael C; Eason, Thomas H; McCown, J Walter; Paetkau, David

2006-02-01

Corridors may mitigate the adverse effects of habitat fragmentation by restoring or maintaining connectivity between disjunct populations. The efficacy of corridors for large carnivores, however has rarely been evaluated objectively. We used noninvasive sampling, microsatellite analysis, and population assignment tests to evaluate the effectiveness of a regional corridor in connecting two Florida black bear (Ursus americanus floridanus) populations (Osceola and Ocala). Bear movement was predominantly unidirectional, with a limited mixing of individuals from the two populations in one area of the corridor We also documented bears in Osceola that were genetically assigned to Ocala and bears in Osceola that may be offspring from an Osceola-Ocala mating. Our results indicate that the Osceola-Ocala corridor is functional and provides a conduit for gene flow between these populations. Human development, however may hinder the use of the Osceola-Ocala corridor by bears. The noninvasive sampling and genetic methods we used provide a means of evaluating corridor effectiveness that can help identify linkages necessary for maintaining metapopulation structure and population viability.

Integrated corridor management initiative: survey Dallas traveler response panel

DOT National Transportation Integrated Search

2017-03-01

This report presents findings from the Integrated Corridor Management (ICM) traveler behavior surveys, a set of panel surveys of US-75 corridor users, conducted before and after the deployment of ICM. The purpose of the surveys was to measure the imp...

Recovery of particulate organic matter dynamics in a stream draining a logged watershed

Treesearch

Jackson Webster; E.J. Benfield; Stephen W. Golladay; Matthew E. McTammany

2014-01-01

Watershed (WS) 7 at Coweeta was logged in 1977. The stream draining this watershed, Big Hurricane Branch, was affected in many ways. While the stream has recovered in some characteristics, the continuing press disturbance limits many aspects of recovery. In this chapter, we report the long-term pattern of recovery of the organic matter dynamics of this stream.

43. Dressing rooms and corridor in basement on west side ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

43. Dressing rooms and corridor in basement on west side of building, looking south. (July 1991) A nearly identical corridor with dressing rooms ran along the east side of the basement, and the two corridors were connected by a short hallway at the north end. The theatre seats seen in hallway in this photo are from Seattle's Orpheum Theatre which was demolished in 1967. - Fox Theater, Seventh Avenue & Olive Way, Seattle, King County, WA

INTERIOR VIEW, EASTWEST CORRIDOR SEEN THROUGH EAST SIDE ENTRY (NOTE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW, EAST-WEST CORRIDOR SEEN THROUGH EAST SIDE ENTRY (NOTE GLASS BLOCK TRANSOM PROVIDING LIGHT INTO CORRIDOR) - Greenbelt Community Building, 15 Crescent Road, Greenbelt, Prince George's County, MD

78 FR 23815 - Northeast Corridor Safety Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-22

.... 6] Northeast Corridor Safety Committee; Notice of Meeting AGENCY: Federal Railroad Administration (FRA), Department of Transportation (DOT). ACTION: Announcement of the Northeast Corridor Safety Committee (NECSC) Meeting. [[Page 23816

Wildfire Effects on In-stream Nutrient Processing and Hydrologic Transport

NASA Astrophysics Data System (ADS)

Rhea, A.; Covino, T. P.; Rhoades, C.; Fegel, T.

2017-12-01

In many forests throughout the Western U.S., drought, climate change, and growing fuel loads are contributing to increased fire frequency and severity. Wildfires can influence watershed nutrient retention as they fundamentally alter the biological composition and physical structure in upland landscapes, riparian corridors, and stream channels. While numerous studies have documented substantial short-term increases in stream nutrient concentrations and export (particularly reactive nitrogen, N) following forest fires, the long-term implications for watershed nutrient cycling remain unclear. For example, recent work indicates that nitrate concentrations and export can remain elevated for a decade or more following wildfire, yet the controls on these processes are unknown. In this research, we use empirical observations from nutrient tracer injections, nutrient diffusing substrates, and continuous water quality monitoring to isolate biological and physical controls on nutrient export across a burn-severity gradient. Tracer results demonstrate substantial stream-groundwater exchange, but little biological nutrient uptake in burned streams. This in part explains patterns of elevated nutrient export. Paired nutrient diffusing substrate experiments allow us to further investigate shifts in N, phosphorus, and carbon limitation that may suppress post-fire stream nutrient uptake. By isolating the mechanisms that reduce the capacity of fire-affected streams to retain and transform nutrient inputs, we can better predict dynamics in post-fire water quality and help prioritize upland and riparian restoration.

North side, enclosed corridor connecting buildings 511 and 515. West ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

North side, enclosed corridor connecting buildings 511 and 515. West side of corridor. - Fitzsimons General Hospital, Infirmary, Northwest Corner of East Bushnell Avenue & South Page Street, Aurora, Adams County, CO

Stream Temperature Estimation From Thermal Infrared Images

NASA Astrophysics Data System (ADS)

Handcock, R. N.; Kay, J. E.; Gillespie, A.; Naveh, N.; Cherkauer, K. A.; Burges, S. J.; Booth, D. B.

2001-12-01

Stream temperature is an important water quality indicator in the Pacific Northwest where endangered fish populations are sensitive to elevated water temperature. Cold water refugia are essential for the survival of threatened salmon when events such as the removal of riparian vegetation result in elevated stream temperatures. Regional assessment of stream temperatures is limited by sparse sampling of temperatures in both space and time. If critical watersheds are to be properly managed it is necessary to have spatially extensive temperature measurements of known accuracy. Remotely sensed thermal infrared (TIR) imagery can be used to derive spatially distributed estimates of the skin temperature (top 100 nm) of streams. TIR imagery has long been used to estimate skin temperatures of the ocean, where split-window techniques have been used to compensate for atmospheric affects. Streams are a more complex environment because 1) most are unresolved in typical TIR images, and 2) the near-bank environment of stream corridors may consist of tall trees or hot rocks and soils that irradiate the stream surface. As well as compensating for atmospheric effects, key problems to solve in estimating stream temperatures include both subpixel unmixing and multiple scattering. Additionally, fine resolution characteristics of the stream surface such as evaporative cooling due to wind, and water surface roughness, will effect measurements of radiant skin temperatures with TIR devices. We apply these corrections across the Green River and Yakima River watersheds in Washington State to assess the accuracy of remotely sensed stream surface temperature estimates made using fine resolution TIR imagery from a ground-based sensor (FLIR), medium resolution data from the airborne MASTER sensor, and coarse-resolution data from the Terra-ASTER satellite. We use linear spectral mixture analysis to isolate the fraction of land-leaving radiance originating from unresolved streams. To compensate the

Highway corridor responsibility

Treesearch

Bonnie L. Harper-Lore

1998-01-01

As highways cross the nation they provide safe travel for the vacationers, commuters, truckers, the military, farmers, congressmen, our families, and friends. Highway corridors provide safe passage for many plant invaders as well. Highway vegetation managers manage millions of acres of rights-of-way that cross your land. It is imperative that we understand each other...

45 CFR 153.540 - Compliance with risk corridors standards.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Section 153.540 Public Welfare Department of Health and Human Services REQUIREMENTS RELATING TO HEALTH CARE ACCESS STANDARDS RELATED TO REINSURANCE, RISK CORRIDORS, AND RISK ADJUSTMENT UNDER THE AFFORDABLE CARE ACT Health Insurance Issuer Standards Related to the Risk Corridors Program § 153.540 Compliance...

Integrated corridor management analysis, modeling, and simulation experimental plan for the test corridor.

DOT National Transportation Integrated Search

2008-03-01

This document, the AMS Experimental Plan, lays out the scope of analysis that will be conducted through the application of the AMS methodology to the Test Corridor. The specific objectives of the Experimental Plan are: create an AMS framework that id...

Abort-once-around entry corridor analysis program document

NASA Technical Reports Server (NTRS)

Kyle, H. C.

1975-01-01

The abort once around entry target corridor analysis program (ABECAP) was studied. The allowable range of flight path angles at entry interface for acceptable entry trajectories from a shuttle abort once around (AOA) situation was established. The solutions thus determined may be shown as corridor plots of entry interface flight path angle versus range from entry interface (EI) to the target.

3. DODGEVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR DODGEVILLE, BRISTOL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. DODGEVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR DODGEVILLE, BRISTOL CO., MA. Sec. 4116, MP 195.55. - Northeast Railroad Corridor, Amtrak Route between RI/MA State Line & South Station, Boston, Suffolk County, MA

1. HEBRONVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR. HEBRONVILLE, BRISTOL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. HEBRONVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR. HEBRONVILLE, BRISTOL CO., MA. Sec. 4116, MP 193.75. - Northeast Railroad Corridor, Amtrak Route between RI/MA State Line & South Station, Boston, Suffolk County, MA

24. View looking north up corridor from Charles Street Bridge. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. View looking north up corridor from Charles Street Bridge. Providence, Providence Co., RI. Sec. 4116, mp 186.44. - Northeast Railroad Corridor, Amtrak route between CT & MA state lines, Providence, Providence County, RI

35. OUTER DRAWBRIDGE, ENTRY TO THE PROTECTIVE CORRIDOR BETWEEN THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

35. OUTER DRAWBRIDGE, ENTRY TO THE PROTECTIVE CORRIDOR BETWEEN THE RAVELIN AND THE CASTILLO, AS SEEN FROM WITHIN THE CORRIDOR - Castillo de San Marcos, 1 Castillo Drive, Saint Augustine, St. Johns County, FL

Nitrogen processing by grazers in a headwater stream: riparian connections

DOE PAGES

Hill, Walter R.; Griffiths, Natalie A.

2016-10-19

Primary consumers play important roles in the cycling of nutrients in headwater streams, storing assimilated nutrients in growing tissue and recycling them through excretion. Though environmental conditions in most headwater streams and their surrounding terrestrial ecosystems vary considerably over the course of a year, relatively little is known about the effects of seasonality on consumer nutrient recycling these streams. Here, we measured nitrogen accumulated through growth and excreted by the grazing snail Elimia clavaeformis (Pleuroceridae) over the course of 12 months in Walker Branch, identifying close connections between in-stream nitrogen processing and seasonal changes in the surrounding forest.

Abort-once-around entry dispersion corridor analysis. [for space shuttle reentry

NASA Technical Reports Server (NTRS)

Kyle, H. C.

1975-01-01

Abort-Once-Around (AOA) entry dispersion corridors were determined for Shuttle Mission 3A. These corridors are presented as plots of entry interface flight path angle versus range to target. The methods used to determine the corridors are discussed. Major dispersion sources are discussed and results presented. While specific trajectory inputs and constraints are subject to change, the dispersion corridors show the trends under consideration. The corridors presented show the delta V advantage of the two-burn over the one-burn AOA. The atmospheric dispersion study illustrates the need to target for the seasonal atmosphere. The 40 deg/30 deg angle of attack (alpha) (TPS design) profile did not provide adequate crossrange capability with worst case aerodynamic dispersions. This problem was alleviated with the change to a 38 deg/28 deg alpha profile. The backface temperatures calculated were generally higher than the present limits.

23. Looking N up corridor from Chick Interlocking Tower. Boston, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. Looking N up corridor from Chick Interlocking Tower. Boston, Suffolk Co., MA. Sec. 4116, MP 227.09. - Northeast Railroad Corridor, Amtrak Route between RI/MA State Line & South Station, Boston, Suffolk County, MA

Rediscovering a Stream in Danville, Kentucky: The Clark Run Corridor and Trails Project.

ERIC Educational Resources Information Center

Bright, Debra

1998-01-01

In Danville, Kentucky, the community cooperated in converting a neglected stream into a walking trail and park network, resulting in increased community pride, environmental awareness, community revitalization, and public-private cooperation. The local middle school regularly tests the water, and the local college's annual clean-up party earned an…

Ice stream behaviour in the western sector of the North Sea during the end of the last glacial cycle

NASA Astrophysics Data System (ADS)

Roberts, David; Evans, David; Clark, Chris; Bateman, Mark; Livingstone, Stephen; Medialdea, Alicia; Cofaigh, Colm O.; Grimoldi, Elena; Callard, Louise; Dove, Dayton; Stewart, Heather; Davies, Bethan; Chiverell, Richard

2016-04-01

During the last glacial cycle the East coast of the UK was overrun by the British-Irish Ice Sheet (BIIS) flowing eastwards and southwards. In recent years it has become evident that several ice streams including the Tweed, Tyne, and Stainmore Gap ice streams, as well as the late stage North Sea Lobe (NSL), all played a role in shaping the glacial landscape during this period, but understanding the flow phasing of these ice streams during advance and collapse has proved challenging. Here we present new data from the seafloor collected during recent work undertaken by the Britice Chrono and Glanam project teams during cruise JC123 in the North Sea. Sub-bottom seafloor data together with new swath data clearly show that the final phases of the collapse of the NSL were controlled by ice sourced from the Firth of Forth ice stream which deglaciated in a NNW trajectory. Other ice streams being fed from the west (e.g. Stainmore, Tyne, Tweed) were not influential in final phase ice retreat from the southern North Sea. The Forth ice imprint is characterised by several grounding zone/till wedges marking dynamic, oscillatory retreat of the ice as it retreated along an offshore corridor between North Yorkshire and Northumberland. Repeated packages of tills, ice marginal and glaciomarine sediments, which drape glacially scoured bedrock terrain and drumlins along this corridor, point to marine inundation accompanying ice retreat. New TCN ages suggest decoupling of the Tyne Gap ice stream and NSL between 17.8 and 16.5 ka and this coincides with rapid, regional collapse of the NSL between 17.2 and 16.0 ka along the Yorkshire and Durham coasts (new OSL ages; Britice Chrono). Hence, both the central and northern sectors of the BIIS were being strongly influenced by marine margin instability during the latter phases of the last glacial cycle.

The effects of a stannous chloride-based water treatment system in a mercury contaminated stream

DOE PAGES

Mathews, Teresa J.; Looney, Brian B.; Smith, John G.; ...

2015-06-09

Remediation of mercury (Hg)-contaminated watersheds is often challenging because of the complex nature of Hg biogeochemistry. Stream ecosystems have been shown to be particularly susceptible to Hg contamination and bioaccumulation in fish. Decreasing total Hg loading to stream systems, however, has shown variable performance in decreasing Hg concentrations in fish tissues. In this study, we assess the impacts of an innovative treatment system in reducing releases of Hg to a small stream system in the southeastern United States. The treatment system, installed in 2007, removes Hg from water using tin (Sn) (II) chloride followed by air stripping. Mercury concentrations inmore » the receiving stream, Tims Branch, decreased from > 100 to ~10 ng/L in the four years following treatment, and Hg body burdens in redfin pickerel ( Esox americanus) decreased by 70 % at the most contaminated site. Tin concentrations in water and fish increased significantly in the tributary leading to Tims Branch, but concentrations remain below levels of concern for human health or ecological risks. While other studies have shown that Sn may be environmentally methylated and methyltin can transfer its methyl group to Hg, results from our field studies and sediment incubation experiments suggest that the added Sn to the Tims Branch watershed is not contributing to MeHg production and bioaccumulation. The stannous chloride treatment system installed at Tims Branch was effective at removing Hg inputs and reducing Hg bioaccumulation in the stream with minimal impacts on the environment due to the increased Sn in the system.« less

77 FR 73734 - Northeast Corridor Safety Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-11

.... 5] Northeast Corridor Safety Committee; Notice of Meeting AGENCY: Federal Railroad Administration (FRA), Department of Transportation (DOT). ACTION: Announcement of a Northeast Corridor Safety... Committee is made up of stakeholders operating on the [[Page 73735

3. GENERAL VIEW OF CORRIDOR AROUND TRENTON STATION. TRENTON, MERCER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. GENERAL VIEW OF CORRIDOR AROUND TRENTON STATION. TRENTON, MERCER CO., NJ. Sec. 1401, MP 56.70. - Northeast Railroad Corridor, Amtrak Route between Pennsylvania/New Jersey & New Jersey/New York State Lines, Newark, Essex County, NJ

The potential of electricity transmission corridors in forested areas as bumblebee habitat.

PubMed

Hill, Bruce; Bartomeus, Ignasi

2016-11-01

Declines in pollinator abundance and diversity are not only a conservation issue, but also a threat to crop pollination. Maintained infrastructure corridors, such as those containing electricity transmission lines, are potentially important wild pollinator habitat. However, there is a lack of evidence comparing the abundance and diversity of wild pollinators in transmission corridors with other important pollinator habitats. We compared the diversity of a key pollinator group, bumblebees ( Bombus spp.), between transmission corridors and the surrounding semi-natural and managed habitat types at 10 sites across Sweden's Uppland region. Our results show that transmission corridors have no impact on bumblebee diversity in the surrounding area. However, transmission corridors and other maintained habitats such as roadsides have a level of bumblebee abundance and diversity comparable to semi-natural grasslands and host species that are important for conservation and ecosystem service provision. Under the current management regime, transmission corridors already provide valuable bumblebee habitat, but given that host plant density is the main determinant of bumblebee abundance, these areas could potentially be enhanced by establishing and maintaining key host plants. We show that in northern temperate regions the maintenance of transmission corridors has the potential to contribute to bumblebee conservation and the ecosystem services they provide.

The potential of electricity transmission corridors in forested areas as bumblebee habitat

PubMed Central

Hill, Bruce

2016-01-01

Declines in pollinator abundance and diversity are not only a conservation issue, but also a threat to crop pollination. Maintained infrastructure corridors, such as those containing electricity transmission lines, are potentially important wild pollinator habitat. However, there is a lack of evidence comparing the abundance and diversity of wild pollinators in transmission corridors with other important pollinator habitats. We compared the diversity of a key pollinator group, bumblebees (Bombus spp.), between transmission corridors and the surrounding semi-natural and managed habitat types at 10 sites across Sweden's Uppland region. Our results show that transmission corridors have no impact on bumblebee diversity in the surrounding area. However, transmission corridors and other maintained habitats such as roadsides have a level of bumblebee abundance and diversity comparable to semi-natural grasslands and host species that are important for conservation and ecosystem service provision. Under the current management regime, transmission corridors already provide valuable bumblebee habitat, but given that host plant density is the main determinant of bumblebee abundance, these areas could potentially be enhanced by establishing and maintaining key host plants. We show that in northern temperate regions the maintenance of transmission corridors has the potential to contribute to bumblebee conservation and the ecosystem services they provide. PMID:28018640

Concept of operations : Dallas Integrated Corridor Management (ICM) demonstration project.

DOT National Transportation Integrated Search

2010-06-01

This concept of operations (Con Ops) for the US-75 Integrated Corridor Management (ICM) Program has been developed as part of the US Department of Transportation Integrated Corridor Management Initiative, which is an innovative research initiative th...

High-speed surface transportation corridor : a conceptual framework, final report.

DOT National Transportation Integrated Search

2009-10-08

Efficient transportation is indispensable for economic growth and prosperity. In this study we propose the development of a high-speed surface corridor and compatible vehicles. We present a conceptual framework for this corridor and vehicle. This pro...

Interior view of main corridor, with doors to shell, powder, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior view of main corridor, with doors to shell, powder, and plotting rooms visible. Corridor to southeast gun chamber on the right - U.S. Naval Base, Pearl Harbor, Battery Adair, Princeton Place, Pearl City, Honolulu County, HI

Interior, looking corridor connecting 511 to 515 into Medical Research ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior, looking corridor connecting 511 to 515 into Medical Research Library in 516. - Fitzsimons General Hospital, Central Service Building, North of Building No. 511, East of corridor connecting Building 511 to Building 515, Aurora, Adams County, CO

General view looking SE at corridor and Pennsylvania Station. Baltimore, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

General view looking SE at corridor and Pennsylvania Station. Baltimore, Baltimore City, MD. Sec. 1201, MP 93.23. - Northeast Railroad Corridor, Amtrak route between District of Columbia/Maryland state line & Maryland/Delaware state line, Baltimore, Independent City, MD

Control Strategies for Corridor Management

DOT National Transportation Integrated Search

2016-06-28

Integrated management of travel corridors comprising of freeways and adjacent arterial streets can potentially improve the performance of the highway facilities. However, several research gaps exist in data collection and performance measurement, ana...

Evaluating Connectivity for two mid-sized mammals Across Riparian Corridors using Wildlife Crossing Monitoring and Species Distribution Modeling

NASA Astrophysics Data System (ADS)

Jeong, S.

2016-12-01

The movement of wildlife can be constrained by river renovation projects owing to the presence of artificial structures. This study evaluates lateral connectivity, the ability to cross from habitat on one side of the river, through riparian vegetation, embankments, and the river to the other, of two mammal species, the leopard cat (Felis bengalensis euptilura) and water deer (Hydropotes inermis). We used 34 months of monitoring on 250 m stream segments on the Seom river, in South Korea to model the lateral connectivity of the stream between suitable habitats on either side of the steam. Habitat suitability within the landscape was determined using species distribution modelingand was used to determine where we thought the animals would want to pass across the river. We compared the predicted crossing locations to observed crossings.We assessed lateral connectivity suitability with maximum entropy and logistic regression models, and species' presences detected from snow tracking, heat sensor cameras, and scat or other signs, as well as landscape variables. Leopard cats prefer upland forest, while water deer prefer the forest edge and riparian corridor. For both target species, the best riparian habitats were characterized by the presence of vegetation cover on the embankment and by at least one side of an embankment being adjacent to farmland or forest cover. The lateral connectivity for the two target species showed different requirements. Water deer cross through large culverts with an openness ratio of 0.7 or under bridges, whereas leopard cats utilized drainage pipes and culvert boxes with a much smaller openness ratio. Stream reaches located close to a river tributary had the highest connectivity values, and areas modeled as good habitat for both species thatlink watershed and riparian habitats showed high connectivity values. Artifacts such as steep banks, concrete embankments, and adjacent roads were found to degrade the lateral connectivity of wildlife

Observations of particulates within the North Atlantic Flight Corridor: POLINAT 2, September-October 1997

NASA Astrophysics Data System (ADS)

Paladino, J. D.; Hagen, D. E.; Whitefield, P. D.; Hopkins, A. R.; Schmid, O.; Wilson, M. R.; Schlager, H.; Schulte, P.

2000-02-01

This paper discusses participate concentration and size distribution data gathered using the University of Missouri-Rolla Mobile Aerosol Sampling System (UMR-MASS), and used to investigate the southern extent of the eastern end of the North Atlantic Flight Corridor (NAFC) during project Pollution From Aircraft Emissions in the North Atlantic Flight Corridor/Subsonic Assessment (SASS) Ozone and Nitrogen Oxide Experiment (POLINAT 2/SONEX) from September 19 to October 23, 1997. The analysis presented in this paper focuses on "the corridor effect," or enhancement of pollutants by jet aircraft combustion events. To investigate the phenomena, both vertical and horizontal profiles of the corridor, and regions immediately adjacent to the corridor, were performed. The profiles showed a time-dependent enhancement of particulates within the corridor, and a nonvolatile (with respect to thermal volatilization at 300°C) aerosol enhancement at corridor altitudes by a factor of 3.6. The southern extent of the North Atlantic Flight Corridor was established from a four flight average of the particulate data and yielded a boundary near 42.5°N during the study period. A size distribution analysis of the nonvolatile particulates revealed an enhancement in the <40 nm particulates for size distributions recorded within the flight corridor.

North Carolina "Sealed Corridor" Phase I, II, and III Assessment

DOT National Transportation Integrated Search

2009-10-01

The Federal Railroad Administration (FRA) tasked the John A. Volpe National Transportation Systems Center to document the further success of the North Carolina DOT "Sealed Corridor" project through Phases I, II, and III. The Sealed Corridor is the se...

BIOTIC INTEGRITY OF STREAMS IN THE SAVANNAH RIVER SITE INTEGRATOR OPERABLE UNITS, 1996 TO 2003

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

Paller, M; Susan Dyer, S

2004-11-08

The Savannah River Site (SRS) has been divided into six Integrator Operable Units (IOUs) that correspond to the watersheds of the five major streams on the SRS (Upper Three Runs, Fourmile Branch, Pen Branch, Steel Creek, and Lower Three Runs) and the portions of the Savannah River and Savannah River Swamp associated with the SRS. The streams are the primary integrators within each IOU because they potentially receive, through surface or subsurface drainage, soluble contaminants from all waste sites within their watersheds. If these contaminants reach biologically significant levels, they would be expected to effect the numbers, types, and healthmore » of stream organisms. In this study, biological sampling was conducted within each IOU as a measure of the cumulative ecological effects of the waste sites within the IOUs. The use of information from biological sampling to assess environmental quality is often termed bioassessment. The IOU bioassessment program included 38 sites in SRS streams and nine sites in the Savannah River. Sampling was conducted in 1996 to 1998, 2000, and 2003. Four bioassessment methods were used to evaluate ecological conditions in the IOU streams: the Index of Biotic Integrity, the Fish Health Assessment Index, measurement of fish tissue contaminant levels, and two benthic macroinvertebrate indices. The Index of Biotic Integrity (IBI) is an EPA supported method based on comparison of ecologically important and sensitive fish assemblage variables between potentially disturbed and reference (i.e., undisturbed) sites. It is designed to assess the ability of a stream to support a self-sustaining biological community and ecological processes typical of undisturbed, natural conditions. Since many types of contaminants can bioaccumulate, fish tissue contaminant data were used to determine the types of chemicals fish were exposed to and their relative magnitudes among IOUs. The Fish Health Assessment Index (HAI) is an EPA supported method for

Restoration of lowland streams: an introduction

USGS Publications Warehouse

Osborne, L.L.; Bayley, P.B.; Higler, L.W.G.; Statzner, B.; Triska, F.; Iverson, T. Moth

1993-01-01

1 This paper introduces the Lowland Streams Restoration Workshop that was held in Lund, Sweden in August 1991.2 Attenders at the Workshop participated in working groups which discussed and reported on the state of knowledge of stream restoration and identified critical areas of information need. Currently, most restoration efforts are emission-orientated (i.e. waste-water management), while the imitation of the geomorphology or of the riparian vegetation of a quasi-natural or natural reference channel receives less attention.3 Successful stream restoration requires a multidisciplinary approach within a holistic system framework. Monitoring the outcome of past, existing and future steam-restoration projects is required for information on the feasibility of alternative techniques and approaches.4 It was recommended that systems in pristine condition serve as a point of reference and not as a goal for most stream restoration projects. Restoration goals must be carefully defined so that everyone at every level understands the aim of the project. At the very least, all restoration programmes should consider geomorphic, hydrological, biological, aesthetic, and water quality aspects of the system.5 Restoration programmes should aim to create a system with a stable channel, or a channel in dynamic equilibrium that supports a self-sustaining and functionally diverse community assemblage; it should not concentrate on one species or group, except at the local level. Preserving the terrestrial -aquatic interface by setting aside riparian land corridors is critical to all stages of restoration. Additional information on the temporal and regional variability in important system processes and functions is needed.

Project management plan : Dallas Integrated Corridor Management (ICM) demonstration project.

DOT National Transportation Integrated Search

2010-12-01

The Dallas Integrated Corridor Management System Demonstration Project is a multi-agency, de-centralized operation which will utilize a set of regional systems to integrate the operations of the corridor. The purpose of the Dallas ICM System is to im...

Northeast rail corridor : information on users, funding sources, and expenditures

DOT National Transportation Integrated Search

1996-06-27

This report describes data on the users of the Northeast Corridor and the : funding needed for its operations and maintenance. It includes the relative use : of the corridor by Amtrak and the commuter and freight railroads, the sources of : funding f...

50. View looking SE down corridor with Hillside Lane Bridge ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

50. View looking SE down corridor with Hillside Lane Bridge in center. Mamaroneck, Westchester Co., NY. Sec. 9108, MP 20.75. - Northeast Railroad Corridor, Amtrak Route between New Jersey/New York & New York/Connecticut State Lines, New York County, NY

9. INTERIOR, SECOND FLOOR, NORTHSOUTH CORRIDOR IN WEST WING, FROM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. INTERIOR, SECOND FLOOR, NORTH-SOUTH CORRIDOR IN WEST WING, FROM ITS INTERSECTION WITH MAIN EAST-WEST CORRIDOR AND NEAR STAIRWELL, LOOKING NORTH. - Oakland Naval Supply Center, Lodge-Cafeteria, East of Fifth Street, between D & E Streets, Oakland, Alameda County, CA

Site-occupany of bats in relation to forested corridors

Treesearch

Chris D Hein; Steven B Castleberry; Karl V. Miller

2009-01-01

Although use of corridors by some wildlife species has been extensively examined, use by bats is poorly understood. From 1 June to 31 August (2004~200S), we used Anabat II detectors to examine bat activity and species occupancy relative to forested corridors on an intensively managed forest landscape in southern South Carolina, USA. We...

North American transportation corridor network

DOT National Transportation Integrated Search

2007-07-01

Trade flows across the three North American countries have increased substantially since the : implementation of the North American Trade Agreement (NAFTA), but there is no movement toward : developing a true North American Transportation Corridor Ne...

Three-Level De-Multiplexed Dual-Branch Complex Delta-Sigma Transmitter.

PubMed

Arfi, Anis Ben; Elsayed, Fahmi; Aflaki, Pouya M; Morris, Brad; Ghannouchi, Fadhel M

2018-02-20

In this paper, a dual-branch topology driven by a Delta-Sigma Modulator (DSM) with a complex quantizer, also known as the Complex Delta Sigma Modulator (CxDSM), with a 3-level quantized output signal is proposed. By de-multiplexing the 3-level Delta-Sigma-quantized signal into two bi-level streams, an efficiency enhancement over the operational frequency range is achieved. The de-multiplexed signals drive a dual-branch amplification block composed of two switch-mode back-to-back power amplifiers working at peak power. A signal processing technique known as quantization noise reduction with In-band Filtering (QNRIF) is applied to each of the de-multiplexed streams to boost the overall performances; particularly the Adjacent Channel Leakage Ratio (ACLR). After amplification, the two branches are combined using a non-isolated combiner, preserving the efficiency of the transmitter. A comprehensive study on the operation of this topology and signal characteristics used to drive the dual-branch Switch-Mode Power Amplifiers (SMPAs) was established. Moreover, this work proposes a highly efficient design of the amplification block based on a back-to-back power topology performing a dynamic load modulation exploiting the non-overlapping properties of the de-multiplexed Complex DSM signal. For experimental validation, the proposed de-multiplexed 3-level Delta-Sigma topology was implemented on the BEEcube™ platform followed by the back-to-back Class-E switch-mode power amplification block. The full transceiver is assessed using a 4th-Generation mobile communications standard LTE (Long Term Evolution) standard 1.4 MHz signal with a peak to average power ratio (PAPR) of 8 dB. The dual-branch topology exhibited a good linearity and a coding efficiency of the transmitter chain higher than 72% across the band of frequency from 1.8 GHz to 2.7 GHz.

Simulation of dynamic expansion, contraction, and connectivity in a mountain stream network

NASA Astrophysics Data System (ADS)

Ward, Adam S.; Schmadel, Noah M.; Wondzell, Steven M.

2018-04-01

Headwater stream networks expand and contract in response to changes in stream discharge. The changes in the extent of the stream network are also controlled by geologic or geomorphic setting - some reaches go dry even under relatively wet conditions, other reaches remain flowing under relatively dry conditions. While such patterns are well recognized, we currently lack tools to predict the extent of the stream network and the times and locations where the network is dry within large river networks. Here, we develop a perceptual model of the river corridor in a headwater mountainous catchment, translate this into a reduced-complexity mechanistic model, and implement the model to examine connectivity and network extent over an entire water year. Our model agreed reasonably well with our observations, showing that the extent and connectivity of the river network was most sensitive to hydrologic forcing under the lowest discharges (Qgauge < 1 L s-1), that at intermediate discharges (1 L s-1 < Qgauge < 10 L s-1) the extent of the network changed dramatically with changes in discharge, and that under wet conditions (Qgauge > 10 L s-1) the extent of the network was relatively insensitive to hydrologic forcing and was instead determined by the network topology. We do not expect that the specific thresholds observed in this study would be transferable to other catchments with different geology, topology, or hydrologic forcing. However, we expect that the general pattern should be robust: the dominant controls will shift from hydrologic forcing to geologic setting as discharge increases. Furthermore, our method is readily transferable as the model can be applied with minimal data requirements (a single stream gauge, a digital terrain model, and estimates of hydrogeologic properties) to estimate flow duration or connectivity along the river corridor in unstudied catchments. As the available information increases, the model could be better calibrated to match site

Scale-dependent genetic structure of the Idaho giant salamander (Dicamptodon aterrimus) in stream networks.

PubMed

Mullen, Lindy B; Arthur Woods, H; Schwartz, Michael K; Sepulveda, Adam J; Lowe, Winsor H

2010-03-01

The network architecture of streams and rivers constrains evolutionary, demographic and ecological processes of freshwater organisms. This consistent architecture also makes stream networks useful for testing general models of population genetic structure and the scaling of gene flow. We examined genetic structure and gene flow in the facultatively paedomorphic Idaho giant salamander, Dicamptodon aterrimus, in stream networks of Idaho and Montana, USA. We used microsatellite data to test population structure models by (i) examining hierarchical partitioning of genetic variation in stream networks; and (ii) testing for genetic isolation by distance along stream corridors vs. overland pathways. Replicated sampling of streams within catchments within three river basins revealed that hierarchical scale had strong effects on genetic structure and gene flow. amova identified significant structure at all hierarchical scales (among streams, among catchments, among basins), but divergence among catchments had the greatest structural influence. Isolation by distance was detected within catchments, and in-stream distance was a strong predictor of genetic divergence. Patterns of genetic divergence suggest that differentiation among streams within catchments was driven by limited migration, consistent with a stream hierarchy model of population structure. However, there was no evidence of migration among catchments within basins, or among basins, indicating that gene flow only counters the effects of genetic drift at smaller scales (within rather than among catchments). These results show the strong influence of stream networks on population structure and genetic divergence of a salamander, with contrasting effects at different hierarchical scales.

Structural connectivity at a national scale: Wildlife corridors in Tanzania.

PubMed

Riggio, Jason; Caro, Tim

2017-01-01

Wildlife corridors can help maintain landscape connectivity but novel methods must be developed to assess regional structural connectivity quickly and cheaply so as to determine where expensive and time-consuming surveys of functional connectivity should occur. We use least-cost methods, the most accurate and up-to-date land conversion dataset for East Africa, and interview data on wildlife corridors, to develop a single, consistent methodology to systematically assess wildlife corridors at a national scale using Tanzania as a case study. Our research aimed to answer the following questions; (i) which corridors may still remain open (i.e. structurally connected) at a national scale, (ii) which have been potentially severed by anthropogenic land conversion (e.g., agriculture and settlements), (iii) where are other remaining potential wildlife corridors located, and (iv) which protected areas with lower forms of protection (e.g., Forest Reserves and Wildlife Management Areas) may act as stepping-stones linking more than one National Park and/or Game Reserve. We identify a total of 52 structural connections between protected areas that are potentially open to wildlife movement, and in so doing add 23 to those initially identified by other methods in Tanzanian Government reports. We find that the vast majority of corridors noted in earlier reports as "likely to be severed" have actually not been cut structurally (21 of 24). Nonetheless, nearly a sixth of all the wildlife corridors identified in Tanzania in 2009 have potentially been separated by land conversion, and a third now pass across lands likely to be converted to human use in the near future. Our study uncovers two reserves with lower forms of protection (Uvinza Forest Reserve in the west and Wami-Mbiki Wildlife Management Area in the east) that act as apparently crucial stepping-stones between National Parks and/or Game Reserves and therefore require far more serious conservation support. Methods used in this

Structural connectivity at a national scale: Wildlife corridors in Tanzania

PubMed Central

Caro, Tim

2017-01-01

Wildlife corridors can help maintain landscape connectivity but novel methods must be developed to assess regional structural connectivity quickly and cheaply so as to determine where expensive and time-consuming surveys of functional connectivity should occur. We use least-cost methods, the most accurate and up-to-date land conversion dataset for East Africa, and interview data on wildlife corridors, to develop a single, consistent methodology to systematically assess wildlife corridors at a national scale using Tanzania as a case study. Our research aimed to answer the following questions; (i) which corridors may still remain open (i.e. structurally connected) at a national scale, (ii) which have been potentially severed by anthropogenic land conversion (e.g., agriculture and settlements), (iii) where are other remaining potential wildlife corridors located, and (iv) which protected areas with lower forms of protection (e.g., Forest Reserves and Wildlife Management Areas) may act as stepping-stones linking more than one National Park and/or Game Reserve. We identify a total of 52 structural connections between protected areas that are potentially open to wildlife movement, and in so doing add 23 to those initially identified by other methods in Tanzanian Government reports. We find that the vast majority of corridors noted in earlier reports as “likely to be severed” have actually not been cut structurally (21 of 24). Nonetheless, nearly a sixth of all the wildlife corridors identified in Tanzania in 2009 have potentially been separated by land conversion, and a third now pass across lands likely to be converted to human use in the near future. Our study uncovers two reserves with lower forms of protection (Uvinza Forest Reserve in the west and Wami-Mbiki Wildlife Management Area in the east) that act as apparently crucial stepping-stones between National Parks and/or Game Reserves and therefore require far more serious conservation support. Methods used in

Improving Urban Corridor that Respect to Public Space

NASA Astrophysics Data System (ADS)

Zahrah, W.; Rahmadhani, N.; Nasution, A. D.; Pane, I. F.

2017-03-01

The urban corridor is more than just a linear space to circulation. It is a place for community activities. Since the urban area in Indonesia functionates without guidelines, it is necessary to analyze how this space being used by the community. The objective of the research is to explore the problems in utilization of public space in Dr. Mansur corridor in Medan and to propose some recommendation to improve it. The survey was started by mapping the physical situation that based on urban design aspects and the activities occur. Based on the data, the study identified the problems of the public space utilization. Next, study selected several buildings that significant in generating public life. The study interviewed the building’s owners and users/customers to get their opinion and perception about the using of urban public space utilization in the corridor in relation to their private function. The study analyzed the problems and opportunity to redesign the buildings that respect to public space. Then, the design ideas were presented to the buildings owners to get their response. The result of the observation shows that the fundamental problem in the corridor is the intervention of the private interest to the street as public space. The study indicates that the majority of the buildings owner was not aware that their buildings had distracted the urban public space. However, they gave a positive respond to the design recommendation. The design offered the solution that provided individual needs without intervention to the public realm. The study can contribute to improving urban corridor by educating the community with architecture and urban design.

Integrated corridor management I-15 San Diego, California : analysis plan.

DOT National Transportation Integrated Search

2010-02-01

This AMS Analysis Plan for the I-15 Corridor outlines the various tasks associated with the application of the ICM AMS tools and strategies to this corridor in order to support benefit-cost assessment for the successful implementation of ICM. The rep...

Longitudinal variability in streamwater chemistry and carbon and nitrogen fluxes in restored and degraded urban stream networks.

PubMed

Sivirichi, Gwendolyn M; Kaushal, Sujay S; Mayer, Paul M; Welty, Claire; Belt, Kenneth T; Newcomer, Tamara A; Newcomb, Katie D; Grese, Melissa M

2011-02-01

Stream restoration has increasingly been used as a best management practice for improving water quality in urbanizing watersheds, yet few data exist to assess restoration effectiveness. This study examined the longitudinal patterns in carbon and nitrogen concentrations and mass balance in two restored (Minebank Run and Spring Branch) and two unrestored (Powder Mill Run and Dead Run) stream networks in Baltimore, Maryland, USA. Longitudinal synoptic sampling showed that there was considerable reach-scale variability in biogeochemistry (e.g., total dissolved nitrogen (TDN), dissolved organic carbon (DOC), cations, pH, oxidation/reduction potential, dissolved oxygen, and temperature). TDN concentrations were typically higher than DOC in restored streams, but the opposite pattern was observed in unrestored streams. Mass balances in restored stream networks showed net uptake of TDN across subreaches (mean ± standard error net uptake rate of TDN across sampling dates for Minebank Run and Spring Branch was 420.3 ± 312.2 and 821.8 ± 570.3 mg m(-2) d(-1), respectively). There was net release of DOC in the restored streams (1344 ± 1063 and 1017 ± 944.5 mg m(-2) d(-1) for Minebank Run and Spring Branch, respectively). Conversely, degraded streams, Powder Mill Run and Dead Run showed mean net release of TDN across sampling dates (629.2 ± 167.5 and 327.1 ± 134.5 mg m(-2) d(-1), respectively) and net uptake of DOC (1642 ± 505.0 and 233.7 ± 125.1 mg m(-2) d(-1), respectively). There can be substantial C and N transformations in stream networks with hydrologically connected floodplain and pond features. Assessment of restoration effectiveness depends strongly on where monitoring is conducted along the stream network. Monitoring beyond the stream-reach scale is recommended for a complete perspective of evaluation of biogeochemical function in restored and degraded urban streams.

Evidence of Fanning in the Ophiuchus Stream

NASA Astrophysics Data System (ADS)

Sesar, Branimir; Price-Whelan, Adrian M.; Cohen, Judith G.; Rix, Hans-Walter; Pearson, Sarah; Johnston, Kathryn V.; Bernard, Edouard J.; Ferguson, Annette M. N.; Martin, Nicolas F.; Slater, Colin T.; Chambers, Kenneth C.; Flewelling, Heather; Wainscoat, Richard J.; Waters, Christopher

2016-01-01

The Ophiuchus stellar stream presents a dynamical puzzle: its old stellar populations (˜12 Gyr) cannot be reconciled with (1) its orbit in a simple model for the Milky Way potential and (2) its short angular extent, both of which imply that the observed stream formed within the last \\lt 1 {{Gyr}}. Recent theoretical work has shown that streams on chaotic orbits may abruptly fan out near their apparent ends; stars in these fans are dispersed in both position and velocity and may be difficult to associate with the stream. Here we present the first evidence of such stream-fanning in the Ophiuchus stream, traced by four blue horizontal branch stars beyond the apparent end of the stream. These stars stand out from the background by their high velocities ({v}{{los}}\\gt 230 km s-1) against ˜40 other stars: their velocities are comparable to those of the stream, but would be exceptional if they were unrelated halo stars. Their positions and velocities are, however, inconsistent with simple extrapolation of the observed cold, high-density portion of the stream. These observations suggest that stream-fanning may be a real, observable effect and, therefore, that Ophiuchus may be on a chaotic orbit. They also show that the Ophiuchus stream is more extended and hence dynamically older than previously thought, easing the stellar population versus dynamical age tension.

Methodology for Collision Risk Assessment of an Airspace Flow Corridor Concept

NASA Astrophysics Data System (ADS)

Zhang, Yimin

This dissertation presents a methodology to estimate the collision risk associated with a future air-transportation concept called the flow corridor. The flow corridor is a Next Generation Air Transportation System (NextGen) concept to reduce congestion and increase throughput in en-route airspace. The flow corridor has the potential to increase throughput by reducing the controller workload required to manage aircraft outside the corridor and by reducing separation of aircraft within corridor. The analysis in this dissertation is a starting point for the safety analysis required by the Federal Aviation Administration (FAA) to eventually approve and implement the corridor concept. This dissertation develops a hybrid risk analysis methodology that combines Monte Carlo simulation with dynamic event tree analysis. The analysis captures the unique characteristics of the flow corridor concept, including self-separation within the corridor, lane change maneuvers, speed adjustments, and the automated separation assurance system. Monte Carlo simulation is used to model the movement of aircraft in the flow corridor and to identify precursor events that might lead to a collision. Since these precursor events are not rare, standard Monte Carlo simulation can be used to estimate these occurrence rates. Dynamic event trees are then used to model the subsequent series of events that may lead to collision. When two aircraft are on course for a near-mid-air collision (NMAC), the on-board automated separation assurance system provides a series of safety layers to prevent the impending NNAC or collision. Dynamic event trees are used to evaluate the potential failures of these layers in order to estimate the rare-event collision probabilities. The results show that the throughput can be increased by reducing separation to 2 nautical miles while maintaining the current level of safety. A sensitivity analysis shows that the most critical parameters in the model related to the overall

Suprachiasmatic translamina terminalis corridor used in endoscopic endonasal approach for resecting third ventricular craniopharyngioma.

PubMed

Gu, Ye; Zhang, Xiaobiao; Hu, Fan; Yu, Yong; Xie, Tao; Sun, Chongjing; Li, Wensheng

2015-05-01

The translamina terminalis corridor was used in the transcranial anterior route to treat third ventricular craniopharyngioma (TVC), which presents a challenge to neurosurgeons. The endoscopic endonasal approach (EEA) has recently been used to treat craniopharyngiomas. However, there are few reports of the EEA being used to treat TVC. The authors' novel surgical approach of treating selected TVC by the endoscopic endonasal route via the suprachiasmatic translamina terminalis (STLT) corridor is described. In this single-center study, the EEA via the STLT corridor was used to resect TVC with great upper and anterior extension causing bulged lamina terminalis, and TVC with a residual upper compartment, after routine infrachiasmatic transmetastalk corridor resection. The STLT corridor was used in 3 patients. Gross-total resection was achieved in all cases. One patient achieved visual improvement, and the other 2 patients showed partial visual improvement. Leakage of CSF occurred in 1 patient. Postoperative hormone replacement therapy was required in all patients. The STLT corridor is a complementary minimally invasive corridor used in the EEA for treating selected TVC. The STLT alone or combined with infrachiasmatic transmetastalk corridors should be selected depending on the size of suprachiasmatic and infrachiasmatic space.

Bison phylogeography constrains dispersal and viability of the Ice Free Corridor in western Canada

PubMed Central

Froese, Duane; Ives, John W.; Zazula, Grant D.; Letts, Brandon; Andrews, Thomas D.; Driver, Jonathan C.; Hall, Elizabeth; Hare, P. Gregory; Jass, Christopher N.; MacKay, Glen; Southon, John R.; Stiller, Mathias; Woywitka, Robin; Suchard, Marc A.

2016-01-01

The Ice Free Corridor has been invoked as a route for Pleistocene human and animal dispersals between eastern Beringia and more southerly areas of North America. Despite the significance of the corridor, there are limited data for when and how this corridor was used. Hypothetical uses of the corridor include: the first expansion of humans from Beringia into the Americas, northward postglacial expansions of fluted point technologies into Beringia, and continued use of the corridor as a contact route between the north and south. Here, we use radiocarbon dates and ancient mitochondrial DNA from late Pleistocene bison fossils to determine the chronology for when the corridor was open and viable for biotic dispersals. The corridor was closed after ∼23,000 until 13,400 calendar years ago (cal y BP), after which we find the first evidence, to our knowledge, that bison used this route to disperse from the south, and by 13,000 y from the north. Our chronology supports a habitable and traversable corridor by at least 13,000 cal y BP, just before the first appearance of Clovis technology in interior North America, and indicates that the corridor would not have been available for significantly earlier southward human dispersal. Following the opening of the corridor, multiple dispersals of human groups between Beringia and interior North America may have continued throughout the latest Pleistocene and early Holocene. Our results highlight the utility of phylogeographic analyses to test hypotheses about paleoecological history and the viability of dispersal routes over time. PMID:27274051

Bison phylogeography constrains dispersal and viability of the Ice Free Corridor in western Canada.

PubMed

Heintzman, Peter D; Froese, Duane; Ives, John W; Soares, André E R; Zazula, Grant D; Letts, Brandon; Andrews, Thomas D; Driver, Jonathan C; Hall, Elizabeth; Hare, P Gregory; Jass, Christopher N; MacKay, Glen; Southon, John R; Stiller, Mathias; Woywitka, Robin; Suchard, Marc A; Shapiro, Beth

2016-07-19

The Ice Free Corridor has been invoked as a route for Pleistocene human and animal dispersals between eastern Beringia and more southerly areas of North America. Despite the significance of the corridor, there are limited data for when and how this corridor was used. Hypothetical uses of the corridor include: the first expansion of humans from Beringia into the Americas, northward postglacial expansions of fluted point technologies into Beringia, and continued use of the corridor as a contact route between the north and south. Here, we use radiocarbon dates and ancient mitochondrial DNA from late Pleistocene bison fossils to determine the chronology for when the corridor was open and viable for biotic dispersals. The corridor was closed after ∼23,000 until 13,400 calendar years ago (cal y BP), after which we find the first evidence, to our knowledge, that bison used this route to disperse from the south, and by 13,000 y from the north. Our chronology supports a habitable and traversable corridor by at least 13,000 cal y BP, just before the first appearance of Clovis technology in interior North America, and indicates that the corridor would not have been available for significantly earlier southward human dispersal. Following the opening of the corridor, multiple dispersals of human groups between Beringia and interior North America may have continued throughout the latest Pleistocene and early Holocene. Our results highlight the utility of phylogeographic analyses to test hypotheses about paleoecological history and the viability of dispersal routes over time.

Mapping mountain torrent hazards in the Hexi Corridor using an evidential reasoning approach

NASA Astrophysics Data System (ADS)

Ran, Youhua; Liu, Jinpeng; Tian, Feng; Wang, Dekai

2017-02-01

The Hexi Corridor is an important part of the Silk Road Economic Belt and a crucial channel for westward development in China. Many important national engineering projects pass through the corridor, such as highways, railways, and the West-to-East Gas Pipeline. The frequent torrent disasters greatly impact the security of infrastructure and human safety. In this study, an evidential reasoning approach based on Dempster-Shafer theory is proposed for mapping mountain torrent hazards in the Hexi Corridor. A torrent hazard map for the Hexi Corridor was generated by integrating the driving factors of mountain torrent disasters including precipitation, terrain, flow concentration processes, and the vegetation fraction. The results show that the capability of the proposed method is satisfactory. The torrent hazard map shows that there is high potential torrent hazard in the central and southeastern Hexi Corridor. The results are useful for engineering planning support and resource protection in the Hexi Corridor. Further efforts are discussed for improving torrent hazard mapping and prediction.

What is The Role of Land Value in The Urban Corridor?

NASA Astrophysics Data System (ADS)

Rakhmatulloh, A. R.; Buchori, I.; Pradoto, W.; Riyanto, B.; Winarendri, J.

2018-02-01

The high movement causes traffic congestion and indicates high movement intensity along the corridor. The higher attraction of the land use will encourage the higher attraction of movement and economic values in the location. This attraction is also affected by the high mobility in the corridor supported by available transport infrastructure. Thus this causes land values become increase significantly. Land use along the corridor can be seen as commercial function because this activity is able to survive in the premium location. The purpose of this research is to identify the effect of land use change toward land values in the commercial corridor. This research used positivistic method with descriptive analysis. The result shows that the land values change in commercial use in the corridor has different pattern of land use change pattern according to physical condition and land use which causes highly economic attraction. The new commercial land is influenced by the distance to city centre or CBD (Central Business District). Land use and public facilities that have local and city scope services do not give the significant impact to land values change.

Courtyard. Left wall is corridor from 511 to 515. Right ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Courtyard. Left wall is corridor from 511 to 515. Right wall is the south side of 517. - Fitzsimons General Hospital, Physiotherapy & Electrocardiograph Department Building, North of Building No. 516, East of corridor connecting Building No. 511 to Building No. 515, Aurora, Adams County, CO

45 CFR 153.510 - Risk corridors establishment and payment methodology.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 45 Public Welfare 1 2013-10-01 2013-10-01 false Risk corridors establishment and payment methodology. 153.510 Section 153.510 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES REQUIREMENTS....510 Risk corridors establishment and payment methodology. (a) General requirement. A QHP issuer must...

Staff corridor (room 206, representing rooms 301, 305, 401, 405, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Staff corridor (room 206, representing rooms 301, 305, 401, 405, 501, and 505), looking south towards the staff corridor vestibule (room 206A, representing rooms 305A, 405A, and 505A). - California State Office Building No. 1, 915 Capitol Mall, Sacramento, Sacramento County, CA

Low-altitude remote sensing dataset of DEM and RGB mosaic for AB corridor on July 13 2013 and L2 corridor on July 21 2013

DOE Data Explorer

Baptiste Dafflon

2015-04-07

Low-altitude remote sensing dataset including DEM and RGB mosaic for AB (July 13 2013) and L2 corridor (July 21 2013).Processing flowchart for each corridor:Ground control points (GCP, 20.3 cm square white targets, every 20 m) surveyed with RTK GPS. Acquisition of RGB pictures using a Kite-based platform. Structure from Motion based reconstruction using hundreds of pictures and GCP coordinates. Export of DEM and RGB mosaic in geotiff format (NAD 83, 2012 geoid, UTM zone 4 north) with pixel resolution of about 2 cm, and x,y,z accuracy in centimeter range (less than 10 cm). High-accuracy and high-resolution inside GCPs zone for L2 corridor (500x20m), AB corridor (500x40) DEM will be updated once all GCPs will be measured. Only zones between GCPs are accurate although all the mosaic is provided.

[Identification of ecological corridors and its importance by integrating circuit theory].

PubMed

Song, Li Li; Qin, Ming Zhou

2016-10-01

Landscape connectivity is considered as an extraordinarily important factor affecting various ecological processes. The least cost path (LCP) on the basis of minimum cumulative resis-tance model (MCRM) may provide a more efficient approach to identify functional connectivity in heterogeneous landscapes, and is already adopted by the research of landscape functional connecti-vity assessment and ecological corridor simulation. Connectivity model on circuit theory (CMCT) replaced the edges in the graph theory with resistors, cost distance with resistance distance to measure the functional connectivity in heterogeneous landscapes. By means of Linkage Mapper tool and Circuitscape software, the simulated landscape generated from SIMMAP 2.0 software was viewed as the study object in this article, aimed at exploring how to integrate MCRM with CMCT to identify ecological corridors and relative importance of landscape factors. The results showed that two models had their individual advantages and mutual complement. MCRM could effectively identify least cost corridors among habitats. CMCT could effectively identify important landscape factor and pinch point, which had important influence on landscape connectivity. We also found that the position of pinch point was not affected by corridor width, which had obvious advantage in the research of identifying the importance of corridors. The integrated method could provide certain scientific basis for regional ecological protection planning and ecological corridor design.

A meteor stream study of 1966

NASA Astrophysics Data System (ADS)

Terentjeva, Alexandra

2017-03-01

3600 individual photographic orbits of meteor bodies and about 2000 visual meteor radiants with corresponding velocities were compiled and carefully studied in detail. 154 minor meteor streams were detected in the Solar System, their basic orbital and other data are given. Firstly some remarkable shower and stream properties are established: examples of the large elliptic radiation areas with semi-major axes perpendicular to the Ecliptic; the existence of the Northern (N) , Southern (S) and Ecliptical (Q) branches of some streams; stream-antipodes and radiant-antipodes (symmetrically arranged relatively to the Ecliptic) with angular distances from the Ecliptic to 40-80°; a number of short-perihelion streams (q 0.05-0.07 A.U.); some meteor streams perpendicular to the Ecliptic's plane. There are also some unique meteor bodies with their orbits enclosed within the limits of the Earth's one, or having the clockwise and anticlockwise direction in two similar orbits. Hyperbolic photographic velocities vh = 57-88 km /sec are treated as real ones according to the best radar and visual observations. A "bunch" of ecliptical streams, discovered in the USSR in 1950, is a complex of orbits of the mostly massive meteor particles of the Zodiacal Cloud. The stream evolution rate is comparatively high. The total complex of sporadic meteor bodies is not totally chaotic and accidental.

Baseline assessment of fish communities, benthic macroinvertebrate communities, and stream habitat and land use, Big Thicket National Preserve, Texas, 1999-2001

USGS Publications Warehouse

Moring, J. Bruce

2003-01-01

The Big Thicket National Preserve comprises 39,300 hectares in the form of nine preserve units connected by four stream corridor units (with two more corridor units proposed) distributed over the lower Neches and Trinity River Basins of southeastern Texas. Fish and benthic macroinvertebrate data were collected at 15 stream sites (reaches) in the preserve during 1999–2001 for a baseline assessment and a comparison of communities among stream reaches. The fish communities in the preserve were dominated by minnows (family Cyprinidae) and sunfishes (family Centrarchidae). Reaches with smaller channel sizes generally had higher fish species richness than the larger reaches in the Neches River and Pine Island Bayou units of the preserve. Fish communities in geographically adjacent reaches were most similar in overall community structure. The blue sucker, listed by the State as a threatened species, was collected in only one reach—a Neches River reach a few miles downstream from the Steinhagen Lake Dam. Riffle beetles (family Elmidae) and midges (family Chironomidae) dominated the aquatic insect communities at the 14 reaches sampled for aquatic insects in the preserve. The Ephemeroptera, Plecoptera and Trichoptera (EPT) Index, an index sensitive to water-quality degradation, was smallest at the Little Pine Island Bayou near Beaumont reach that is in a State 303(d)-listed stream segment on Little Pine Island Bayou. Trophic structure of the aquatic insect communities is consistent with the river continuum concept with shredder and scraper insect taxa more abundant in reaches with smaller stream channels and filter feeders more abundant in reaches with larger channels. Aquatic insect community metrics were not significantly correlated to any of the stream-habitat or land-use explanatory variables. The percentage of 1990s urban land use in the drainage areas upstream from 12 bioassessment reaches were negatively correlated to the reach structure index, which indicates

Quality of Streams in Johnson County, Kansas, and Relations to Environmental Variables, 2003-07

USGS Publications Warehouse

Rasmussen, Teresa J.; Poulton, Barry C.; Graham, Jennifer L.

2009-01-01

The quality of streams and relations to environmental variables in Johnson County, northeastern Kansas, were evaluated using water, streambed sediment, land use, streamflow, habitat, algal periphyton (benthic algae), and benthic macroinvertebrate data. Water, streambed sediment, and macroinvertebrate samples were collected in March 2007 during base flow at 20 stream sites that represent 11 different watersheds in the county. In addition, algal periphyton samples were collected twice (spring and summer 2007) at one-half of the sites. Environmental data including water and streambed-sediment chemistry data (primarily nutrients, fecal-indicator bacteria, and organic wastewater compounds), land use, streamflow, and habitat data were used in statistical analyses to evaluate relations between biological conditions and variables that may affect them. This report includes an evaluation of water and streambed-sediment chemistry, assessment of habitat conditions, comparison of biological community attributes (such as composition, diversity, and abundance) among sampling sites, placement of sampling sites into impairment categories, evaluation of biological data relative to environmental variables, and evaluation of changes in biological communities and effects of urbanization. This evaluation is useful for understanding factors that affect stream quality, for improving water-quality management programs, and for documenting changing conditions over time. The information will become increasingly important for protecting streams in the future as urbanization continues. Results of this study indicate that the biological quality at nearly all biological sampling sites in Johnson County has some level of impairment. Periphyton taxa generally were indicative of somewhat degraded conditions with small to moderate amounts of organic enrichment. Camp Branch in the Blue River watershed was the only site that met State criteria for full support of aquatic life in 2007. Since 2003

Design Analysis of Corridors-in-the-Sky

NASA Technical Reports Server (NTRS)

Xue, Min

2008-01-01

Corridors-in-the-sky or tubes is one of new concepts in dynamic airspace configuration. It accommodates high density traffic, which has similar trajectories. Less air traffic controllers workload is expected than classic airspaces, thus, corridors-in-the-sky may increase national airspace capacity and reduce flight delays. To design corridors-in-the-sky, besides identifying their locations, their utilization, altitudes, and impacts on remaining system need to be analyzed. This paper chooses one tube candidate and presents analyses of spatial and temporal utilization of the tube, the impact on the remaining traffic, and the potential benefit caused by off-loading the traffic from underlying sectors. Fundamental issues regarding to the benefits have been also clarified. Methods developed to assist the analysis are described. Analysis results suggest dynamic tubes in terms of varied utilizations during different time periods. And it is found that combined lane options would be a good choice to lower the impact on non-tube users. Finally, it shows significant reduction of peak aircraft count in underlying sectors with only one tube enabled.

45 CFR 153.510 - Risk corridors establishment and payment methodology.

Code of Federal Regulations, 2012 CFR

2012-10-01

... methodology. 153.510 Section 153.510 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES REQUIREMENTS RELATING TO HEALTH CARE ACCESS STANDARDS RELATED TO REINSURANCE, RISK CORRIDORS, AND RISK ADJUSTMENT UNDER THE AFFORDABLE CARE ACT Health Insurance Issuer Standards Related to the Risk Corridors Program § 153...

45 CFR 153.510 - Risk corridors establishment and payment methodology.

Code of Federal Regulations, 2014 CFR

2014-10-01

... methodology. 153.510 Section 153.510 Public Welfare Department of Health and Human Services REQUIREMENTS RELATING TO HEALTH CARE ACCESS STANDARDS RELATED TO REINSURANCE, RISK CORRIDORS, AND RISK ADJUSTMENT UNDER THE AFFORDABLE CARE ACT Health Insurance Issuer Standards Related to the Risk Corridors Program § 153...

13. I95 bridge crossing corridor with Providence Station in background. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. I-95 bridge crossing corridor with Providence Station in background. Providence, Providence County, RI. sec. 4116, mp 185.15. - Northeast Railroad Corridor, Amtrak route between CT & MA state lines, Providence, Providence County, RI

Wake-Vortex Separation Distances when Flight-Path Corridors are Constrained

NASA Technical Reports Server (NTRS)

Rossow, Vernon J.; Olson, Lawrence E. (Technical Monitor)

1995-01-01

Since the vortex wakes of large transport aircraft can pose a hazard to smaller following aircraft during landing and takeoff operations, certain separation guidelines are followed while aircraft are in the approach and departure corridors at airports. These guidelines reduce the capacity of airports because the separation distances are larger than other airport factors require. This paper studies the effect that a decrease in the size of the cross-section of the flight corridors for air traffic control would have on the wake-vortex separation guidelines; e.g., when the Global Positioning System (GPS) is implemented for air traffic control. It is first shown why smaller flight corridors permit reduced spacings at airports. Several arrangements of smaller flight corridors are then presented to illustrate how differing atmospheric and airport conditions can be accommodated. These considerations indicate that a reduction is then permissible in the wake-vortex spacings while still retaining the same or an improved degree of safety.

River corridor science: Hydrologic exchange and ecological consequences from bedforms to basins

USGS Publications Warehouse

Harvey, Judson; Gooseff, Michael

2015-01-01

Previously regarded as the passive drains of watersheds, over the past 50 years, rivers have progressively been recognized as being actively connected with off-channel environments. These connections prolong physical storage and enhance reactive processing to alter water chemistry and downstream transport of materials and energy. Here we propose river corridor science as a concept that integrates downstream transport with lateral and vertical exchange across interfaces. Thus, the river corridor, rather than the wetted river channel itself, is an increasingly common unit of study. Main channel exchange with recirculating marginal waters, hyporheic exchange, bank storage, and overbank flow onto floodplains are all included under a broad continuum of interactions known as “hydrologic exchange flows.” Hydrologists, geomorphologists, geochemists, and aquatic and terrestrial ecologists are cooperating in studies that reveal the dynamic interactions among hydrologic exchange flows and consequences for water quality improvement, modulation of river metabolism, habitat provision for vegetation, fish, and wildlife, and other valued ecosystem services. The need for better integration of science and management is keenly felt, from testing effectiveness of stream restoration and riparian buffers all the way to reevaluating the definition of the waters of the United States to clarify the regulatory authority under the Clean Water Act. A major challenge for scientists is linking the small-scale physical drivers with their larger-scale fluvial and geomorphic context and ecological consequences. Although the fine scales of field and laboratory studies are best suited to identifying the fundamental physical and biological processes, that understanding must be successfully linked to cumulative effects at watershed to regional and continental scales.

River corridor science: Hydrologic exchange and ecological consequences from bedforms to basins

NASA Astrophysics Data System (ADS)

Harvey, Jud; Gooseff, Michael

2015-09-01

Previously regarded as the passive drains of watersheds, over the past 50 years, rivers have progressively been recognized as being actively connected with off-channel environments. These connections prolong physical storage and enhance reactive processing to alter water chemistry and downstream transport of materials and energy. Here we propose river corridor science as a concept that integrates downstream transport with lateral and vertical exchange across interfaces. Thus, the river corridor, rather than the wetted river channel itself, is an increasingly common unit of study. Main channel exchange with recirculating marginal waters, hyporheic exchange, bank storage, and overbank flow onto floodplains are all included under a broad continuum of interactions known as "hydrologic exchange flows." Hydrologists, geomorphologists, geochemists, and aquatic and terrestrial ecologists are cooperating in studies that reveal the dynamic interactions among hydrologic exchange flows and consequences for water quality improvement, modulation of river metabolism, habitat provision for vegetation, fish, and wildlife, and other valued ecosystem services. The need for better integration of science and management is keenly felt, from testing effectiveness of stream restoration and riparian buffers all the way to reevaluating the definition of the waters of the United States to clarify the regulatory authority under the Clean Water Act. A major challenge for scientists is linking the small-scale physical drivers with their larger-scale fluvial and geomorphic context and ecological consequences. Although the fine scales of field and laboratory studies are best suited to identifying the fundamental physical and biological processes, that understanding must be successfully linked to cumulative effects at watershed to regional and continental scales.

Evaluation of high trash corridors.

DOT National Transportation Integrated Search

2002-03-01

The objectives of this study were to: a) determine a procedure to use to identify corridors in each highway district for which a detailed analysis of crash data should be conducted (with resulting increased law enforcement activities, education progr...

Grizzly bears and calving caribou: What is the relation with river corridors?

USGS Publications Warehouse

Young, Donald D.; McCabe, Thomas R.

1998-01-01

Researchers have debated the effect of the Trans-Alaska Pipeline (TAP) and associated developments to caribou (Rangifer tarandus) of the central Arctic herd (CAH) since the 1970s. Several studies have demonstrated that cows and calves of the CAH avoided the TAP corridor because of disturbance associated with the pipeline, whereas others have indicated that female caribou of the CAH avoided riparian habitats closely associated with the pipeline. This avoidance was explained as a predator-avoidance strategy. We investigated the relation between female caribou and grizzly bear (Ursus arctos) use of river corridors on the yet undisturbed calving grounds of the Porcupine caribou herd (PCH) in northeastern Alaska. On the coastal plain, caribou were closer to river corridors than expected (P = 0.038), but bear use of river corridors did not differ from expected (P = 0.740). In the foothills, caribou use of river corridors did not differ from expected (P = 0.520), but bears were farther from rivers than expected (P = 0.001). Our results did not suggest an avoidance of river corridors by calving caribou or a propensity for bears to be associated with riparian habitats, presumably for stalking or ambush cover. We propose that PCH caribou reduce the risks of predation to neonates by migrating to a common calving grounds, where predator swamping is the operational antipredator strategy. Consequently, we hypothesize that nutritional demands, not predator avoidance strategies, ultimately regulate habitat use patterns (e.g., use of river corridors) of calving PCH caribou.

Stream Phosphorus Dynamics Along a Suburbanizing Gradient in Southern Ontario, Canada

NASA Astrophysics Data System (ADS)

Duval, T. P.

2017-12-01

While it is well known that urban streams are subject to impaired water quality relative to natural analogues, far less research has been directed at stream water quality during the process of (sub-) urbanization. This study determines the role of housing construction activities in Brampton, Canada on the concentration and flux of phosphorus (P) of a headwater stream. Prior to development the stream was engineered with a riffle-pool sequence, riparian plantings, and a floodplain corridor that was lined with sediment fencing. Stream sites were sampled daily over a period of six months at locations representing varying stages of subdivision completion (upper site -active construction; middle site -finished construction and natural vegetation; lower site -finished construction and active construction). A nearby urban stream site developed ten years prior to this study was selected as a reference site. There were no differences in total phosphorus (TP) levels or flux between the suburbanizing and urban streams; however, the forms of P differed between sites. The urban stream TP load was dominated by particulate phosphorus (PP) while suburbanizing stream P was mainly in the dissolved organic phosphorus (DOP) form. The importance of DOP to TP flux increased with the onset of the growing season. TP levels in all stream segments frequently exceeded provincial water quality guidelines during storm events but were generally low during baseflow conditions. During storm events PP and total suspended solid levels in the suburbanizing stream reached levels of the urban stream due to sediment fence failure at several locations along the construction-hillslope interface. Along the suburbanizing gradient, the hydrological connection to a mid-reach zone of no-construction activity / fallow field and native forest resulted in significantly lower P levels than the upper suburbanizing stream site. This suggests that stream channel design features as well as timing of construction

Potential metrics for designating and monitoring oversize/overweight corridors : final report.

DOT National Transportation Integrated Search

2016-11-11

This report: - Discusses how oversize/overweight (OS/OW) corridors are currently designated in Texas. - Provides information on OS/OW corridors as detailed in the Texas Transportation Code. - Lists potential metrics (as identified by stakeholder work...

System acceptance test plan : Dallas Integrated Corridor Management (ICM) demonstration project.

DOT National Transportation Integrated Search

2013-02-01

The Dallas Area Rapid Transit (DART) is leading the US 75 Integrated Corridor Management (ICM) Demonstration Project for the Dallas region. Coordinated corridor operations and management is predicated on being able to share transportation information...

75 FR 48359 - Blackstone River Valley National Heritage Corridor Commission: Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-10

... Corridor Commission: Notice of Meeting Notice is hereby given in accordance with Section 552b of Title 5... Corridor Commission will be held on Thursday, September 16, 2010. The Commission was established pursuant... waters within the Corridor. The meeting will convene on September 16, 2010 at 9 a.m. at Slater Mill...

Flow directionality, mountain barriers and functional traits determine diatom metacommunity structuring of high mountain streams.

PubMed

Dong, Xiaoyu; Li, Bin; He, Fengzhi; Gu, Yuan; Sun, Meiqin; Zhang, Haomiao; Tan, Lu; Xiao, Wen; Liu, Shuoran; Cai, Qinghua

2016-04-19

Stream metacommunities are structured by a combination of local (environmental filtering) and regional (dispersal) processes. The unique characters of high mountain streams could potentially determine metacommunity structuring, which is currently poorly understood. Aiming at understanding how these characters influenced metacommunity structuring, we explored the relative importance of local environmental conditions and various dispersal processes, including through geographical (overland), topographical (across mountain barriers) and network (along flow direction) pathways in shaping benthic diatom communities. From a trait perspective, diatoms were categorized into high-profile, low-profile and motile guild to examine the roles of functional traits. Our results indicated that both environmental filtering and dispersal processes influenced metacommunity structuring, with dispersal contributing more than environmental processes. Among the three pathways, stream corridors were primary pathway. Deconstructive analysis suggested different responses to environmental and spatial factors for each of three ecological guilds. However, regardless of traits, dispersal among streams was limited by mountain barriers, while dispersal along stream was promoted by rushing flow in high mountain stream. Our results highlighted that directional processes had prevailing effects on metacommunity structuring in high mountain streams. Flow directionality, mountain barriers and ecological guilds contributed to a better understanding of the roles that mountains played in structuring metacommunity.

18. View looking NE up corridor showing Wards Island Viaduct ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

18. View looking NE up corridor showing Wards Island Viaduct in foreground and Randalls Island Viaduct in background. Wards Island, New York Co., NY. Sec. 4207, MP 8.02. - Northeast Railroad Corridor, Amtrak Route between New Jersey/New York & New York/Connecticut State Lines, New York County, NY

Relationships between acid deposition, watershed characteristics, and stream chemistry in Maryland's coastal plain. Final report. Volume 5. Appendix B. 4

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

Campbell, S.; Bartoshesky, J.; Heimbuch, D.

1987-06-01

Contents include: data quality assurance and stream, precipitation, and meteorological data; Granny Finley Branch stream chemistry (routine sampling, storm-event chemistry, longitudinal sampling, groundwater chemistry).

Moving shadows contribute to the corridor illusion in a chimpanzee (Pan troglodytes).

PubMed

Imura, Tomoko; Tomonaga, Masaki

2009-08-01

Previous studies have reported that backgrounds depicting linear perspective and texture gradients influence relative size discrimination in nonhuman animals (known as the "corridor illusion"), but research has not yet identified the other kinds of depth cues contributing to the corridor illusion. This study examined the effects of linear perspective and shadows on the responses of a chimpanzee (Pan troglodytes) to the corridor illusion. The performance of the chimpanzee was worse when a smaller object was presented at the farther position on a background reflecting a linear perspective, implying that the corridor illusion was replicated in the chimpanzee (Imura, Tomonaga, & Yagi, 2008). The extent of the illusion changed as a function of the position of the shadows cast by the objects only when the shadows were moving in synchrony with the objects. These findings suggest that moving shadows and linear perspective contributed to the corridor illusion in a chimpanzee. Copyright 2009 APA, all rights reserved.

[Perception and attitude of rural community to the construction of Asian elephant conservation corridors in Xishuangbanna].

PubMed

Li, Zheng-Ling; Chen, Ming-Yong; Wu, Zhao-Lu; Wang, Qian; Dong, Yong-Hua

2009-06-01

By using contingent valuation method (CVM), an investigation was made from November 2007 to March 2008 on the perception and attitude of 196 households in 5 villages within 2 planned Asian elephant conservation corridors in Xishuangbanna to the construction of the corridors. 80.61% of the interviewees conditionally supported the corridors construction. The main factors affecting the interviewees' support willingness included their education level, per capita income, and perceptions to Asian elephant protection, human-elephant relations, and corridor utilization patterns and its beneficiaries, among which, the interviewees' awareness of Asian elephant conservation, corridor utilization patterns, and corridor beneficiaries had strong influence on the support willingness, with the correlation coefficient being 0.231, 0.236, and -0.304, respectively. The rural community holding the land tenure played a key role in the corridors construction. To effectively design and planning the construction of biological conservation corridor, it is necessary to have a deep understanding on the perceptions and attitudes of rural community to the construction of the corridor and to obtain their support and participation for this construction.

How and Why Does Stream Water Temperature Vary at Small Spatial Scales in a Headwater Stream?

NASA Astrophysics Data System (ADS)

Morgan, J. C.; Gannon, J. P.; Kelleher, C.

2017-12-01

The temperature of stream water is controlled by climatic variables, runoff/baseflow generation, and hyporheic exchange. Hydrologic conditions such as gaining/losing reaches and sources of inflow can vary dramatically along a stream on a small spatial scale. In this work, we attempt to discern the extent that the factors of air temperature, groundwater inflow, and precipitation influence stream temperature at small spatial scales along the length of a stream. To address this question, we measured stream temperature along the perennial stream network in a 43 ha catchment with a complex land use history in Cullowhee, NC. Two water temperature sensors were placed along the stream network on opposite sides of the stream at 100-meter intervals and at several locations of interest (i.e. stream junctions). The forty total sensors recorded the temperature every 10 minutes for one month in the spring and one month in the summer. A subset of sampling locations where stream temperature was consistent or varied from one side of the stream to the other were explored with a thermal imaging camera to obtain a more detailed representation of the spatial variation in temperature at those sites. These thermal surveys were compared with descriptions of the contributing area at the sample sites in an effort to discern specific causes of differing flow paths. Preliminary results suggest that on some branches of the stream stormflow has less influence than regular hyporheic exchange, while other tributaries can change dramatically with stormflow conditions. We anticipate this work will lead to a better understanding of temperature patterns in stream water networks. A better understanding of the importance of small-scale differences in flow paths to water temperature may be able to inform watershed management decisions in the future.

75 FR 64741 - Blackstone River Valley National Heritage Corridor Commission: Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-20

... Corridor Commission: Notice of Meeting Notice is hereby given in accordance with Section 552b of Title 5... Corridor Commission will be held on Friday, November 19, 2010. The Commission was established pursuant to... Corridor. The meeting will convene on November 19, 2010 at 9 a.m. at Brigham Hill Community Barn located at...

75 FR 2885 - Blackstone River Valley National Heritage Corridor Commission: Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-19

... Corridor Commission: Notice of Meeting Notice is hereby given in accordance with Section 552b of Title 5... Corridor Commission will be held on Thursday, February 25, 2010. The Commission was established pursuant to... Corridor. The meeting will convene on February 25, 2010 at 9 a.m. at the Woonsocket City Hall located at...

75 FR 17756 - Blackstone River Valley National Heritage Corridor Commission: Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-07

... Corridor Commission: Notice of Meeting Notice is hereby given in accordance with Section 552b of Title 5... Corridor Commission will be held on Thursday, May 20, 2010. The Commission was established pursuant to... Corridor. The meeting will convene on May 20, 2010 at 9 a.m. at Atria Draper Place located at 25 Hopedale...

Mobilisation of traffic-derived trace metals from road corridors into coastal stream and estuarine sediments, Cairns, northern Australia

NASA Astrophysics Data System (ADS)

Pratt, C.; Lottermoser, B. G.

2007-04-01

This investigation revealed the presence of traffic-derived metals within road, stream and estuarine sediments collected from a coastal catchment, northern Australia. Studied road sediments displayed variable total metal concentrations (median Cd, Cu, Pb, Pd, Pt, Ni and Zn values: 0.19, 42.6, 67.5, 0.064, 0.104, 36.7 and 698 mg/kg, respectively). The distinctly elevated Zn values are due to abundant tyre rubber shreds (as verified by SEM-EDS and correlation analysis). By comparison to the road sediments, background stream sediments taken upstream from roads have relatively low median Pb, Pd, Pt and Zn concentrations (7.3 mg/kg Pb, 0.01 mg/kg Pd, 0.012 mg/kg Pt, 62 mg/kg Zn). Stream and estuarine sediment samples collected below roads have median values of 21.8 mg/kg Pb, 0.014 mg/kg Pd, 0.021 mg/kg Pt and 71 mg/kg Zn, and exhibit 207Pb/206Pb and 208Pb/206Pb ratios that appear on a mixing line between the isotopically distinct background stream sediments and the road sediments. Thus, mobilisation of dusts and sediments from road surfaces has resulted in relatively elevated Pb, Pd, Pt and Zn concentrations and non-radiogenic Pb isotope ratios in local coastal stream and estuarine sediments. The investigation demonstrates that traffic-derived metals enter coastal stream and estuary sediments at the fringe of the Great Barrier Reef lagoon.

Novel Insights Linking Ecological Health to Biogeochemical Hotspots across the Groundwater-Surface Water Interface in Mixed Land Use Stream Systems

NASA Astrophysics Data System (ADS)

McKnight, U. S.; Sonne, A. T.; Rasmussen, J. J.; Rønde, V.; Traunspurger, W.; Höss, S.; Bjerg, P. L.

2017-12-01

Increasing modifications in land use and water management have resulted in multiple stressors impacting freshwater ecosystems globally. Chemicals with the potential to impact aquatic habitats are still often evaluated individually for their adverse effects on ecosystem health. This may lead to critical underestimations of the combined impact caused by interactions occurring between stressors not typically evaluated together, e.g. xenobiotic groundwater pollutants and trace metals. To address this issue, we identified sources and levels of chemical stressors along a 16-km groundwater-fed stream corridor (Grindsted, Denmark), representative for a mixed land use stream system. Potential pollution sources included two contaminated sites (factory, landfill), aquaculture, wastewater/industrial discharges, and diffuse sources from agriculture and urban areas. Ecological status was determined by monitoring meiobenthic and macrobenthic invertebrate communities.The stream was substantially impaired by both geogenic and anthropogenic sources of metals throughout the investigated corridor, with concentrations close to or above threshold values for barium, copper, lead, nickel and zinc in the stream water, hyporheic zone and streambed sediment. The groundwater plume from the factory site caused elevated concentrations of chlorinated ethenes, benzene and pharmaceuticals in both the hyporheic zone and stream, persisting for several km downstream. Impaired ecological conditions, represented by a lower abundance of meiobenthic individuals, were found in zones where the groundwater plume discharges to the stream. The effect was only pronounced in areas characterized by high xenobiotic organic concentrations and elevated dissolved iron and arsenic levels - linked to the dissolution of iron hydroxides caused by the degradation of xenobiotic compounds in the plume. The results thus provide ecological evidence for the interaction of organic and inorganic chemical stressors, which may

Prevertebral corridor: posterior pathway for reconstruction of the ventral skull base.

PubMed

Durmaz, Abdullah; Fernandez-Miranda, Juan; Snyderman, Carl H; Rivera-Serrano, Carlos; Tosun, Fuat

2011-05-01

Regional vascularized flaps, such as the pericranial and temporoparietal fascia flaps, are currently used for reconstruction of skull base defects after endoscopic endonasal surgery whenever local vascularized flaps, such as the nasoseptal flap, are not available. Two different transposition pathways, infratemporal transpterygoid and subfrontal, have been proposed for regional flaps. The objective of this study was to describe and assess the feasibility of the transposition of a vascularized pedicled flap from the occipital galeopericranium via the prevertebral space corridor into the nasopharynx. Ten heads were injected with colored silicone. An endoscopic endonasal anterior craniofacial resection and panclival approach were performed in each specimen. The occipital flap was harvested using a previously described technique. The prevertebral corridor, extending from the neck to the nasopharynx, was dissected superficial to the paraspinal muscles. Computed tomography-based image guidance was used to assess the relationship between the corridor and adjacent neurovascular structures. Length of the corridor and pedicle and area of the donor flap were measured. The flap was harvested and successfully transposed into the nasopharynx using the proposed corridor in all studied specimens (10 heads, 20 sides). All flaps provided complete coverage of the skull base defects. The average length of the pedicle was 70.5 (SD, 6.5) mm, and the average length and width of the flap were 99.9 (SD, 14.6) mm and 59.3 (SD, 10.9) mm, respectively. The average length of the prevertebral corridor was 49.7 (SD, 4.8) mm. The occipital flap has favorable anatomic characteristics for use in skull base reconstruction. Transposition of the flap via the prevertebral corridor is a suitable option for vascularized reconstruction of expanded endonasal skull base defects when other local or regional flaps are not available. Additional clinical studies are necessary to define its role in endoscopic

1. GENERAL VIEW, LOOKING SOUTH DOWN CORRIDOR, SHOWING RIDLEY PARK ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. GENERAL VIEW, LOOKING SOUTH DOWN CORRIDOR, SHOWING RIDLEY PARK STATION WITH SELLERS AVENUE BRIDGE, SWARTHMORE AVENUE BRIDGE, AND PEDESTRIAN BRIDGE CROSSING TRACKS. RIDLEY PARK, DELAWARE CO., PA. Sec. 1201, MP 10.42. - Northeast Railroad Corridor, Amtrak route between Delaware-Pennsylvania & Pennsylvania-New Jersey state lines, Philadelphia, Philadelphia County, PA

76 FR 29290 - Environmental Impact Statement: Interstate 64 Hampton Roads Bridge Tunnel Corridor, Virginia

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-20

...: Interstate 64 Hampton Roads Bridge Tunnel Corridor, Virginia AGENCY: Federal Highway Administration (FHWA... Interstate 64 Hampton Roads Bridge Tunnel (HRBT) corridor in Virginia. FOR FURTHER INFORMATION CONTACT... Interstate 64 Hampton Roads Bridge Tunnel (HRBT) corridor in Virginia. The approximate limits of the study...

Riparian corridors enhance movement of a forest specialist bird in fragmented tropical forest.

PubMed

Gillies, Cameron S; St Clair, Colleen Cassady

2008-12-16

Riparian corridors and fencerows are hypothesized to increase the persistence of forest animals in fragmented landscapes by facilitating movement among suitable habitat patches. This function may be critically important for forest birds, which have declined dramatically in fragmented habitats. Unfortunately, direct evidence of corridor use has been difficult to collect at landscape scales and this limits support for corridors in conservation planning. Using telemetry and handheld GPS units, we examined the movement of forest birds by translocating territorial individuals of barred antshrikes (Thamnophilus doliatus; a forest specialist) and rufous-naped wrens (Campylorhynchus rufinucha; a forest generalist) 0.7-1.9 km from their territories in the highly fragmented tropical dry forest of Costa Rica. In each translocation, the directly intervening habitat comprised 1 of 3 treatments: forested riparian corridor, linear living fencerow, or open pasture. Antshrikes returned faster and with greater success in riparian corridors relative to pasture treatments. This species also traveled more directly in riparian corridor treatments, detoured to use forested routes in the other 2 treatments, and did not use fencerows even when they led directly to their home territories. By contrast, wrens were more likely to use fencerows when returning, and return time and success were equivalent among the 3 treatments. Both species crossed fewer gaps in tree cover during riparian corridor treatments than in fencerow or pasture treatments. We conclude that antshrikes, which may be representative of other forest specialists, use forested corridors for movement in this landscape and that fencerows are avoided as movement conduits.

5. Corridor A and Building No. 9962A (with white door). ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. Corridor A and Building No. 9962-A (with white door). In upper left is east side of Building No. 9952-B. - Madigan Hospital, Corridors & Ramps, Bounded by Wilson & McKinley Avenues & Garfield & Lincoln Streets, Tacoma, Pierce County, WA

The Steiner Multigraph Problem: Wildlife corridor design for multiple species

Treesearch

Katherine J. Lai; Carla P. Gomes; Michael K. Schwartz; Kevin S. McKelvey; David E. Calkin; Claire A. Montgomery

2011-01-01

The conservation of wildlife corridors between existing habitat preserves is important for combating the effects of habitat loss and fragmentation facing species of concern. We introduce the Steiner Multigraph Problem to model the problem of minimum-cost wildlife corridor design for multiple species with different landscape requirements. This problem can also model...

Evaluation of the Corridor Safety Improvement Program : phase 1 final report.

DOT National Transportation Integrated Search

1997-09-01

This project is an analysis of Oregon's Corridor Safety Improvement Programs implemented on Oregon Route 22 and Oregon Route 34. Improvements were : made along each corridor in 1993. : The project used a mail-out survey to determine the level of awar...

Carbon stock corridors to mitigate climate change and promote biodiversity in the tropics

NASA Astrophysics Data System (ADS)

Jantz, Patrick; Goetz, Scott; Laporte, Nadine

2014-02-01

A key issue in global conservation is how biodiversity co-benefits can be incorporated into land use and climate change mitigation activities, particularly those being negotiated under the United Nations to reduce emissions from tropical deforestation and forest degradation. Protected areas have been the dominant strategy for tropical forest conservation and they have increased substantially in recent decades. Avoiding deforestation by preserving carbon stored in vegetation between protected areas provides an opportunity to mitigate the effects of land use and climate change on biodiversity by maintaining habitat connectivity across landscapes. Here we use a high-resolution data set of vegetation carbon stock to map corridors traversing areas of highest biomass between protected areas in the tropics. The derived corridors contain 15% of the total unprotected aboveground carbon in the tropical region. A large number of corridors have carbon densities that approach or exceed those of the protected areas they connect, suggesting these are suitable areas for achieving both habitat connectivity and climate change mitigation benefits. To further illustrate how economic and biological information can be used for corridor prioritization on a regional scale, we conducted a multicriteria analysis of corridors in the Legal Amazon, identifying corridors with high carbon, high species richness and endemism, and low economic opportunity costs. We also assessed the vulnerability of corridors to future deforestation threat.

An Assessment of Hydrology, Fluvial Geomorphology, and Stream Ecology in the Cardwell Branch Watershed, Nebraska, 2003-04

USGS Publications Warehouse

Rus, David L.; Dietsch, Benjamin J.; Woodward, Brenda K.; Fry, Beth E.; Wilson, Richard C.

2007-01-01

An assessment of the 16.3-square-mile Cardwell Branch watershed characterized the hydrology, fluvial geomorphology, and stream ecology in 2003-04. The study - performed by the U.S. Geological Survey in cooperation with the City of Lincoln, Nebraska, and the Lower Platte South Natural Resources District - focused on the 7.7-square-mile drainage downstream from Yankee Hill Reservoir. Hydrologic and hydraulic models were developed using the Hydrologic Modeling System (HEC-HMS) and River Analysis System (HEC-RAS) of the U.S. Army Corps of Engineers Hydraulic Engineering Center. Estimates of streamflow and water-surface elevation were simulated for 24-hour-duration design rainstorms ranging from a 50-percent frequency to a 0.2-percent frequency. An initial HEC-HMS model was developed using the standardized parameter estimation techniques associated with the Soil Conservation Service curve number technique. An adjusted HEC-HMS model also was developed in which parameters were adjusted in order for the model output to better correspond to peak streamflows estimated from regional regression equations. Comparisons of peak streamflow from the two HEC-HMS models indicate that the initial HEC-HMS model may better agree with the regional regression equations for higher frequency storms, and the adjusted HEC-HMS model may perform more closely to regional regression equations for larger, rarer events. However, a lack of observed streamflow data, coupled with conflicting results from regional regression equations and local high-water marks, introduced considerable uncertainty into the model simulations. Using the HEC-RAS model to estimate water-surface elevations associated with the peak streamflow, the adjusted HEC-HMS model produced average increases in water-surface elevation of 0.2, 1.1, and 1.4 feet for the 50-, 1-, and 0.2-percent-frequency rainstorms, respectively, when compared to the initial HEC-HMS model. Cross-sectional surveys and field assessments conducted between

Effects of weighting schemes on the identification of wildlife corridors generated with least-cost methods.

PubMed

Parks, Sean A; McKelvey, Kevin S; Schwartz, Michael K

2013-02-01

The importance of movement corridors for maintaining connectivity within metapopulations of wild animals is a cornerstone of conservation. One common approach for determining corridor locations is least-cost corridor (LCC) modeling, which uses algorithms within a geographic information system to search for routes with the lowest cumulative resistance between target locations on a landscape. However, the presentation of multiple LCCs that connect multiple locations generally assumes all corridors contribute equally to connectivity, regardless of the likelihood that animals will use them. Thus, LCCs may overemphasize seldom-used longer routes and underemphasize more frequently used shorter routes. We hypothesize that, depending on conservation objectives and available biological information, weighting individual corridors on the basis of species-specific movement, dispersal, or gene flow data may better identify effective corridors. We tested whether locations of key connectivity areas, defined as the highest 75th and 90th percentile cumulative weighted value of approximately 155,000 corridors, shift under different weighting scenarios. In addition, we quantified the amount and location of private land that intersect key connectivity areas under each weighting scheme. Some areas that appeared well connected when analyzed with unweighted corridors exhibited much less connectivity compared with weighting schemes that discount corridors with large effective distances. Furthermore, the amount and location of key connectivity areas that intersected private land varied among weighting schemes. We believe biological assumptions and conservation objectives should be explicitly incorporated to weight corridors when assessing landscape connectivity. These results are highly relevant to conservation planning because on the basis of recent interest by government agencies and nongovernmental organizations in maintaining and enhancing wildlife corridors, connectivity will likely

Endoscopic endonasal approach to the anteromedial temporal fossa and mobilization of the lateral wall of the cavernous sinus through the inferior orbital fissure and V1-V2 corridor: An anatomical study and clinical considerations.

PubMed

Hanakita, Shunya; Chang, Wei-Chieh; Watanabe, Kentaro; Ronconi, Daniel; Labidi, Moujahed; Park, Hun-Ho; Oyama, Kenichi; Bernat, Anne-Laure; Froelich, Sebastien

2018-04-27

The aim of this study was to identify key anatomical landmarks useful in gaining access to the anteromedial temporal region via the corridor formed by the inferior orbital fissure (IOF), the ophthalmic branch (V1), and the maxillary branch (V2) of the trigeminal nerve via the EEA. An anatomical dissection of six cadaver heads was performed to confirm the feasibility and applicability of the EEA for accessing the anteromedial temporal region. Following middle turbinectomy, the lateral recess of the sphenoid sinus was opened, the orbital apex exposed, and the posterior wall of the maxillary sinus was removed, in sequence. The IOF and the pterygopalatine fossa (PPF) were then identified. After opening the foramen rotundum (FR) and removing the bony structure between the FR, V2 was transposed downward. The orbital muscle of Müller was removed. The PPF was mobilized downward exposing the greater wing of the sphenoid bone (GWS). The GWS between V1 and V2 was drilled, thus exposing the temporal dura. With blunt dissection, the medial temporal dura was peeled away from the cavernous sinus (CS) in order to increase access to the anteromedial temporal region. In this study, the anteromedial temporal fossa was exposed by drilling the V1-V2 triangle corridor via the EEA. Endoscopic endonasal exposure of the anteromedial temporal fossa is feasible and requires limited endonasal work. This approach may be considered as an alternate surgical corridor to the temporomesial lobe that offers the advantages of a direct route with less temporal lobe retraction. Copyright © 2018. Published by Elsevier Inc.

14 CFR 93.305 - Flight-free zones and flight corridors.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Flight-free zones and flight corridors. 93... Vicinity of Grand Canyon National Park, AZ § 93.305 Flight-free zones and flight corridors. Except in an... Flight Rules Area within the following flight-free zones: (a) Desert View Flight-free Zone. That airspace...

14 CFR 93.305 - Flight-free zones and flight corridors.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Flight-free zones and flight corridors. 93... Vicinity of Grand Canyon National Park, AZ § 93.305 Flight-free zones and flight corridors. Except in an... Flight Rules Area within the following flight-free zones: (a) Desert View Flight-free Zone. That airspace...

14 CFR 93.305 - Flight-free zones and flight corridors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flight-free zones and flight corridors. 93... Vicinity of Grand Canyon National Park, AZ § 93.305 Flight-free zones and flight corridors. Except in an... Flight Rules Area within the following flight-free zones: (a) Desert View Flight-free Zone. That airspace...

14 CFR 93.305 - Flight-free zones and flight corridors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Flight-free zones and flight corridors. 93... Vicinity of Grand Canyon National Park, AZ § 93.305 Flight-free zones and flight corridors. Except in an... Flight Rules Area within the following flight-free zones: (a) Desert View Flight-free Zone. That airspace...

14 CFR 93.305 - Flight-free zones and flight corridors.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Flight-free zones and flight corridors. 93... Vicinity of Grand Canyon National Park, AZ § 93.305 Flight-free zones and flight corridors. Except in an... Flight Rules Area within the following flight-free zones: (a) Desert View Flight-free Zone. That airspace...

A corridor on the first floor of the building, looking ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

A corridor on the first floor of the building, looking west, shows some of the typical interior finishes in this section. At the end of the hallway, the corridor turns right after entering the next adjacent structure - Department of Energy, Mound Facility, Electronics Laboratory Building (E Building), One Mound Road, Miamisburg, Montgomery County, OH

Third report on the Oak Ridge K-25 Site Biological Monitoring and Abatement Program for Mitchell Branch

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

Hinzman, R.L.; Adams, S.M.; Ashwood, T.L.

1995-08-01

As a condition of the modified National Pollutant Discharge Elimination System (NPDES) permit issued to the Oak Ridge Gaseous Diffusion Plant (ORGDP; now referred to as the Oak Ridge K-25 Site) on September 11, 1986, a Biological Monitoring and Abatement Program (BMAP) was developed for the receiving stream (Mitchell Branch or K-1700 stream). On October 1, 1992, a renewed NPDES permit was issued for the K-25 Site. A biological monitoring plan was submitted for Mitchell Branch, Poplar Creek, Poplar Creek Embayment of the Clinch River and any unnamed tributaries of these streams. The objectives of BMAP are to (1) demonstratemore » that the effluent limitations established for the Oak Ridge K-25 Site protect and maintain the use of Mitchell Branch for growth and propagation of fish and other aquatic life and (2) document the effects on stream biota resulting from operation of major new pollution abatement facilities, including the Central Neutralization Facility (CNF) and the Toxic Substances Control Act (TSCA) incinerator. The BMAP consists of four tasks: (1) toxicity monitoring; (2) bioaccumulation monitoring; (3) assessment of fish health; and (4) instream monitoring of biological communities, including benthic macroinvertebrates and fish. This document, the third in a series, reports on the results of the Oak Ridge K-25 Site BMAP; it describes studies that were conducted over various periods of time between June 1990 and December 1993, although monitoring conducted outside this time period is included, as appropriate.« less

Trucking and Size and Weight Regulations in the Mid-Continent Corridor

DOT National Transportation Integrated Search

1996-11-01

This thesis is an empirical analysis of trucking and truck size and weight (TS&W) regulations in the Mid-continent corridor. Based on this analysis, it compares and contrasts plausible near term TS&W policy options relating to this corridor. The appr...

China Pakistan Economic Corridor (CPEC): Benefits For Pakistan And Comparison With Suez And Panama Canals

DTIC Science & Technology

2017-12-01

ECONOMIC CORRIDOR (CPEC): BENEFITS FOR PAKISTAN AND COMPARISON WITH SUEZ AND PANAMA CANALS by Hanif Ullah Khan December 2017 Thesis...DATE December 2017 3. REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE CHINA PAKISTAN ECONOMIC CORRIDOR (CPEC): BENEFITS FOR...The China Pakistan Economic Corridor (CPEC) is part of China’s “One Belt, One Road” initiative and joins two major economic corridors: The Silk Road

36 CFR 13.1108 - Alsek Corridor.

Code of Federal Regulations, 2012 CFR

2012-07-01

... River. (e) Disposal of solid human body waste within the Alsek Corridor is prohibited. This waste must... a permit is prohibited. (b) Group size is limited to 15 persons except that specific concession...

36 CFR 13.1108 - Alsek Corridor.

Code of Federal Regulations, 2013 CFR

2013-07-01

... River. (e) Disposal of solid human body waste within the Alsek Corridor is prohibited. This waste must... a permit is prohibited. (b) Group size is limited to 15 persons except that specific concession...

36 CFR 13.1108 - Alsek Corridor.

Code of Federal Regulations, 2011 CFR

2011-07-01

... River. (e) Disposal of solid human body waste within the Alsek Corridor is prohibited. This waste must... a permit is prohibited. (b) Group size is limited to 15 persons except that specific concession...

24. General view looking NE up the corridor towards downtown ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. General view looking NE up the corridor towards downtown Newark with NJ State Highway ramp to Broad Street in center and Lehigh Valley Railroad Bridge in right corner. Newark, Essex Co., NJ. Sec. 1401, MP 10.35. - Northeast Railroad Corridor, Amtrak Route between Pennsylvania/New Jersey & New Jersey/New York State Lines, Newark, Essex County, NJ

MTR WING, TRA604, INTERIOR. BASEMENT. WEST CORRIDOR. CAMERA FACES NORTH. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

MTR WING, TRA-604, INTERIOR. BASEMENT. WEST CORRIDOR. CAMERA FACES NORTH. HVAC AREA IS AT RIGHT OF CORRIDOR. INL NEGATIVE NO. HD46-13-3. Mike Crane, Photographer, 2/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Identifying Corridors among Large Protected Areas in the United States.

PubMed

Belote, R Travis; Dietz, Matthew S; McRae, Brad H; Theobald, David M; McClure, Meredith L; Irwin, G Hugh; McKinley, Peter S; Gage, Josh A; Aplet, Gregory H

2016-01-01

Conservation scientists emphasize the importance of maintaining a connected network of protected areas to prevent ecosystems and populations from becoming isolated, reduce the risk of extinction, and ultimately sustain biodiversity. Keeping protected areas connected in a network is increasingly recognized as a conservation priority in the current era of rapid climate change. Models that identify suitable linkages between core areas have been used to prioritize potentially important corridors for maintaining functional connectivity. Here, we identify the most "natural" (i.e., least human-modified) corridors between large protected areas in the contiguous Unites States. We aggregated results from multiple connectivity models to develop a composite map of corridors reflecting agreement of models run under different assumptions about how human modification of land may influence connectivity. To identify which land units are most important for sustaining structural connectivity, we used the composite map of corridors to evaluate connectivity priorities in two ways: (1) among land units outside of our pool of large core protected areas and (2) among units administratively protected as Inventoried Roadless (IRAs) or Wilderness Study Areas (WSAs). Corridor values varied substantially among classes of "unprotected" non-core land units, and land units of high connectivity value and priority represent diverse ownerships and existing levels of protections. We provide a ranking of IRAs and WSAs that should be prioritized for additional protection to maintain minimal human modification. Our results provide a coarse-scale assessment of connectivity priorities for maintaining a connected network of protected areas.

Identification of functional corridors with movement characteristics of brown bears on the Kenai Peninsula, Alaska

USGS Publications Warehouse

Graves, T.A.; Farley, S.; Goldstein, M.I.; Servheen, C.

2007-01-01

We identified primary habitat and functional corridors across a landscape using Global Positioning System (GPS) collar locations of brown bears (Ursus arctos). After deriving density, speed, and angular deviation of movement, we classified landscape function for a group of animals with a cluster analysis. We described areas with high amounts of sinuous movement as primary habitat patches and areas with high amounts of very directional, fast movement as highly functional bear corridors. The time between bear locations and scale of analysis influenced the number and size of corridors identified. Bear locations should be collected at intervals ???6 h to correctly identify travel corridors. Our corridor identification technique will help managers move beyond the theoretical discussion of corridors and linkage zones to active management of landscape features that will preserve connectivity. ?? 2007 Springer Science+Business Media, Inc.

The role of green corridors for wildlife conservation in urban landscape: A literature review

NASA Astrophysics Data System (ADS)

Aziz, H. A.; Rasidi, M. H.

2014-02-01

Green corridors are an attempt to mitigate negative effects of the built environment of cities and towns. The corridors act as conservation for rapidly extreme intervention and development of the urban environment. Most importantly, it enables dispersal movement of animals within city areas. Issues relate to wildlife conservation in urban areas has been studied for many years and thus, the research makes a review for how the green corridors contribute to the conservation of urban wildlife. This study reviews groups of articles in disciplines of urban landscape planning and biology conservation to discuss the relationship between elements of green corridors and urban wildlife dispersal movement behaviour in Malaysian context. Accordingly, this research is purposely studied to give understanding on how green corridors contribute to the animals' ability of moving and dispersing within the built-up areas. In advance, it is found that there are three factors contribute to the capability of colonization among urban wildlife which are individual, physical and social factor. Green corridor has been defined as one of the physical factor that influence urban wildlife behaviour movement. Consequently, safety area indicating to animals species for traversing in any time such as at night can be defined as the primary potential corridor.

Oil pipeline corridor through an intact forest alters ground beetle (Coleoptera: Carabidae) assemblages in southeastern Ohio.

PubMed

Silverman, Bareena; Horn, David J; Purrington, Foster F; Gandhi, Kamal J K

2008-06-01

Litter-dwelling ground beetle (Coleoptera: Carabidae) assemblages were monitored 1 yr after the construction of a corridor for installation of an oil pipeline along a xeric ridge-top forest in southeastern Ohio. After the creation of the corridor, three distinct habitats were evident in these sites: open corridor, ecotone areas around the corridor, and undisturbed forest interior. Carabidae were collected using directional pitfall traps that were placed parallel and perpendicular to the corridor in each of the three habitats. Results indicate that more carabids were present in the ecotone than in the other two habitats. Carabid diversity as estimated by rarefaction was highest in the corridor followed by ecotone and forest interior. Generalist and forest specialists such as Synuchus impunctatus (Say), Carabus goryi Dejean, and Pterostichus trinarius (Casey) were present in greater numbers in the forest interior and ecotone assemblages. In contrast, open-habitat specialists such as Harpalus pensylvanicus (DeGeer) and Selenophorus opalinus (LeConte) were present in greater numbers in the corridor assemblages. Carabid assemblages of the corridor were distinct from those of the ecotone and forest interior, whereas the latter two habitats had very similar assemblages. The successional pathway of the corridor carabid assemblage will therefore be likely different from that of the forest interior and ecotone. Overall, results indicate that construction of the oil pipeline corridor had significant short-term effects on the carabid numbers, diversity, and species composition because of ensuing habitat changes and fragmentation of the forest.

Northeast corridor passenger transportation data study

DOT National Transportation Integrated Search

1976-08-31

Fourteen measures of performance are recommended for use in Northeast Corridor rail system evaluation and multimodal comparisons. These include performance measures in the categories of system configuration (e.g., daily available-seat miles by vehicl...

Managing Corridor Development. A Municipal Handbook

DOT National Transportation Integrated Search

1996-10-01

The challenge of managing corridor development lies in the dynamic interaction between transportation and land use. The land use plan used to predict transportation needs inevitably changes as new highways stimulate real estate speculation, rezoning,...

FRACOR-software toolbox for deterministic mapping of fracture corridors in oil fields on AutoCAD platform

NASA Astrophysics Data System (ADS)

Ozkaya, Sait I.

2018-03-01

Fracture corridors are interconnected large fractures in a narrow sub vertical tabular array, which usually traverse entire reservoir vertically and extended for several hundreds of meters laterally. Fracture corridors with their huge conductivities constitute an important element of many fractured reservoirs. Unlike small diffuse fractures, actual fracture corridors must be mapped deterministically for simulation or field development purposes. Fracture corridors can be identified and quantified definitely with borehole image logs and well testing. However, there are rarely sufficient image logs or well tests, and it is necessary to utilize various fracture corridor indicators with varying degrees of reliability. Integration of data from many different sources, in turn, requires a platform with powerful editing and layering capability. Available commercial reservoir characterization software packages, with layering and editing capabilities, can be cost intensive. CAD packages are far more affordable and may easily acquire the versatility and power of commercial software packages with addition of a small software toolbox. The objective of this communication is to present FRACOR, a software toolbox which enables deterministic 2D fracture corridor mapping and modeling on AutoCAD platform. The FRACOR toolbox is written in AutoLISPand contains several independent routines to import and integrate available fracture corridor data from an oil field, and export results as text files. The resulting fracture corridor maps consists mainly of fracture corridors with different confidence levels from combination of static and dynamic data and exclusion zones where no fracture corridor can exist. The exported text file of fracture corridors from FRACOR can be imported into an upscaling programs to generate fracture grid for dual porosity simulation or used for field development and well planning.

Hydrogeochemical data from an acidic deposition study at McDonalds Branch basin in the New Jersey Pinelands, 1983-86

USGS Publications Warehouse

Lord, D.G.; Barringer, J.L.; Johnsson, P.A.; Schuster, P.F.; Walker, R.L.; Fairchild, J.E.; Sroka, B.N.; Jacobsen, Eric

1990-01-01

Data from a 1983-86 acidic-deposition study at McDonalds Branch basin, a small (2.35-sq-mi) forested watershed in Lebanon State Forest, New Jersey include mineralogy of soil and depositional clays; physical and chemical analyses of soils; hydrologic measurements (precipitation and throughfall amounts, stream stage and discharge, and water-table altitudes); and water quality data from precipitation, throughfall, soil water, surface water, and groundwater. Site locations, collector designs, and well- construction data also are presented. The pH of bulk precipitation to McDonalds Branch basin over the sampling period (January 1985 to March 1986) ranged from 4.0 to 4.7, with a mean of approximately 4.3. Stream pH ranged from 3.2 to 4.8 and generally increased in a downstream direction. In general sulfate was the dominant anion throughout the basin. Aluminum concentrations commonly were elevated in surface and groundwaters, and were as high as 10,000 micrograms/L at one upstream site on McDonalds Branch. Dissolved organic carbon was an important component of stream waters in some locations and ranged in concentration from 1/1 to 37 mg/L. (USGS)

Integrated Corridor Traffic Management Evaluation Report

DOT National Transportation Integrated Search

2000-04-01

In 1993, the Minnesota Department of Transportation (Mn/DOT) forged a partnership with Hennepin County and the cities of Bloomington Richfield, and Edina to test the concept of integrated corridor traffic management (ICTM) across jurisdictional bound...

ITS Projects In The Northeast Corridor

DOT National Transportation Integrated Search

1996-01-01

THIS DOCUMENT CONTAINS BRIEF DESCRIPTIONS OF ITS PROJECTS RECENTLY COMPLETED, UNDERWAY OR PLANNED WITHIN THE NORTHEAST CORRIDOR. THE BASIC SOURCE OF THIS INFORMATION IS FROM THE SPONSORING AGENCIES ALTHOUGH OTHER SECONDARY SOURCES HAVE ALSO BEEN USED...

Assessment of water chemistry, habitat, and benthic macroinvertebrates at selected stream-quality monitoring sites in Chester County, Pennsylvania, 1998-2000

USGS Publications Warehouse

Reif, Andrew G.

2004-01-01

Biological, chemical, and habitat data have been collected from a network of sites in Chester County, Pa., from 1970 to 2003 to assess stream quality. Forty sites in 6 major stream basins were sampled between 1998 and 2000. Biological data were used to determine levels of impairment in the benthic-macroinvertebrate community in Chester County streams and relate the impairment, in conjunction with chemical and habitat data, to overall stream quality. Biological data consisted of benthic-macroinvertebrate samples that were collected annually in the fall. Water-chemistry samples were collected and instream habitat was assessed in support of the biological sampling.Most sites in the network were designated as nonimpacted or slightly impacted by human activities or extreme climatic conditions on the basis of biological-metric analysis of benthic-macroinvertebrate data. Impacted sites were affected by factors, such as nutrient enrichment, erosion and sedimentation, point discharges, and droughts and floods. Streams in the Schuylkill River, Delaware River, and East Branch Brandywine Creek Basins in Chester County generally had low nutrient concentrations, except in areas affected by wastewater-treatment discharges, and stream habitat that was affected by erosion. Streams in the West Branch Brandywine, Christina, Big Elk, and Octoraro Creek Basins in Chester County generally had elevated nutrient concentrations and streambottom habitat that was affected by sediment deposition.Macroinvertebrate communities identified in samples from French Creek, Pigeon Creek (Schuylkill River Basin), and East Branch Brandywine Creek at Glenmoore consistently indicate good stream conditions and were the best conditions measured in the network. Macroinvertebrate communities identified in samples from Trout Creek (site 61), West Branch Red Clay Creek (site 55) (Christina River Basin), and Valley Creek near Atglen (site 34) (Octoraro Creek Basin) indicated fair to poor stream conditions and

Trade-offs and efficiencies in optimal budget-constrained multispecies corridor networks

Treesearch

Bistra Dilkina; Rachel Houtman; Carla P. Gomes; Claire A. Montgomery; Kevin S. McKelvey; Katherine Kendall; Tabitha A. Graves; Richard Bernstein; Michael K. Schwartz

2016-01-01

Conservation biologists recognize that a system of isolated protected areas will be necessary but insufficient to meet biodiversity objectives. Current approaches to connecting core conservation areas through corridors consider optimal corridor placement based on a single optimization goal: commonly, maximizing the movement for a target species across a...

Concept of operations for the US-75 integrated corridor in Dallas, Texas

DOT National Transportation Integrated Search

2008-04-30

This Concept of Operations (Con Ops) for the US-75 Integrated Corridor Management (ICM) Program has been developed as part of the Federal Highway Administration, the Federal Transit Administration, and RITA (FHWA/FTA/RITA) Integrated Corridor Managem...

Contralateral transmaxillary corridor: an augmented endoscopic approach to the petrous apex.

PubMed

Patel, Chirag R; Wang, Eric W; Fernandez-Miranda, Juan C; Gardner, Paul A; Snyderman, Carl H

2017-10-20

OBJECTIVE The endoscopic endonasal approach (EEA) has been shown to be an effective means of accessing lesions of the petrous apex. Lesions that are lateral to the paraclival segment of the internal carotid artery (ICA) require lateralization of the paraclival segment of the ICA or a transpterygoid infrapetrous approach. In this study the authors studied the feasibility of adding a contralateral transmaxillary (CTM) corridor to provide greater access to the petrous apex with decreased need for manipulation of the ICA. METHODS Using image guidance, EEA and CTM extension were performed bilaterally on 5 cadavers. The anterior wall of the sphenoid sinus and rostrum were removed. The angle of the surgical approach from the axis of the petrous segment of the ICA was measured. Five illustrative clinical cases are presented. RESULTS The CTM corridor required a partial medial maxillectomy. When measured from the axis of the petrous ICA, the CTM corridor decreased the angle from 44.8° ± 2.78° to 20.1° ± 4.31°, a decrease of 24.7° ± 2.58°. Drilling through the CTM corridor allowed the drill to reach lateral aspects of the petrous apex that would have required lateralization of the ICA or would not have been accessible via EEA. The CTM corridor allowed us to achieve gross-total resection of the petrous apex region in 5 clinical cases with significant paraclival extension. CONCLUSIONS The CTM corridor is a feasible extension to the standard EEA to the petrous apex that offers a more lateral trajectory with improved access. This approach may reduce the risk and morbidity associated with manipulation of the paraclival ICA.

Fixed-Wing Micro Aerial Vehicle for Accurate Corridor Mapping

NASA Astrophysics Data System (ADS)

Rehak, M.; Skaloud, J.

2015-08-01

In this study we present a Micro Aerial Vehicle (MAV) equipped with precise position and attitude sensors that together with a pre-calibrated camera enables accurate corridor mapping. The design of the platform is based on widely available model components to which we integrate an open-source autopilot, customized mass-market camera and navigation sensors. We adapt the concepts of system calibration from larger mapping platforms to MAV and evaluate them practically for their achievable accuracy. We present case studies for accurate mapping without ground control points: first for a block configuration, later for a narrow corridor. We evaluate the mapping accuracy with respect to checkpoints and digital terrain model. We show that while it is possible to achieve pixel (3-5 cm) mapping accuracy in both cases, precise aerial position control is sufficient for block configuration, the precise position and attitude control is required for corridor mapping.

Effects of landscape corridors on seed dispersal by birds.

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

Levey, Douglas, J.; Bolker, Benjamin M.; Tewksbury, Joshua J.

2005-07-01

Levey, Douglas, J., Benjamin M. Bolker, Joshua J. Tewksbury, Sarah Sargent, and Nick M. Haddad. 2005. Effects of landscape corridors on seed dispersal by birds. Science 309:146-148. Abstract: Habitat fragmentation threatens biodiversity by disrupting dispersal. The mechanisms and consequences of this disruption are controversial, primarily because most organisms are difficult to track. We examined the effect of habitat corridors on long-distance dispersal of seeds by birds, and tested whether small-scale (G20 meters) movements of birds could be scaled up to predict dispersal of seeds across hundreds of meters in eight experimentally fragmented landscapes. A simulation model accurately predicted the observedmore » pattern of seed rain and revealed that corridors functioned through edge following behavior of birds. Our study shows how models based on easily observed behaviors can be scaled up to predict landscape-level processes.« less

Simulation of groundwater flow and streamflow depletion in the Branch Brook, Merriland River, and parts of the Mousam River watersheds in southern Maine

USGS Publications Warehouse

Nielsen, Martha G.; Locke, Daniel B.

2015-01-01

The study evaluated two different methods of calculating in-stream flow requirements for Branch Brook and the Merriland River—a set of statewide equations used to calculate monthly median flows and the MOVE.1 record-extension technique used on site-specific streamflow measurements. The August median in-stream flow requirement in the Merriland River was calculated as 7.18 ft3/s using the statewide equations but was 3.07 ft3/s using the MOVE.1 analysis. In Branch Brook, the August median in-stream flow requirements were calculated as 20.3 ft3/s using the statewide equations and 11.8 ft3/s using the MOVE.1 analysis. In each case, using site-specific data yields an estimate of in-stream flow that is much lower than an estimate the statewide equations provide.

A Stream Morphology Classification for Eco-hydraulic Purposes Based on Geospatial Data: a Solute Transport Application Case

NASA Astrophysics Data System (ADS)

Jiménez Jaramillo, M. A.; Camacho Botero, L. A.; Vélez Upegui, J. I.

2010-12-01

Variation in stream morphology along a basin drainage network leads to different hydraulic patterns and sediment transport processes. Moreover, solute transport processes along streams, and stream habitats for fisheries and microorganisms, rely on stream corridor structure, including elements such as bed forms, channel patterns, riparian vegetation, and the floodplain. In this work solute transport processes simulation and stream habitat identification are carried out at the basin scale. A reach-scale morphological classification system based on channel slope and specific stream power was implemented by using digital elevation models and hydraulic geometry relationships. Although the morphological framework allows identification of cascade, step-pool, plane bed and pool-riffle morphologies along the drainage network, it still does not account for floodplain configuration and bed-forms identification of those channel types. Hence, as a first application case in order to obtain parsimonious three-dimensional characterizations of drainage channels, the morphological framework has been updated by including topographical floodplain delimitation through a Multi-resolution Valley Bottom Flatness Index assessing, and a stochastic bed form representation of the step-pool morphology. Model outcomes were tested in relation to in-stream water storage for different flow conditions and representative travel times according to the Aggregated Dead Zone -ADZ- model conceptualization of solute transport processes.

76 FR 31009 - Iowa Northern Railway Company-Operation Exemption-North Central Iowa Rail Corridor, LLC

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-27

... Railway Company--Operation Exemption--North Central Iowa Rail Corridor, LLC Iowa Northern Railway Company...) Docket No. FD 35507, North Central Iowa Rail Corridor, LLC--Acquisition Exemption--Union Pacific Railroad Company, in which North Central Iowa Rail Corridor, LLC seeks to acquire from Union Pacific Railroad...

Physically Modeling Stream Channel Adjustment to Woody Riparian Vegetation

NASA Astrophysics Data System (ADS)

Bennett, S. J.; Alonso, C. V.

2003-12-01

Stream restoration designs often use vegetation to promote bank and channel stability, to facilitate point-bar development, and to encourage natural colonization of riparian species. Here we examine the adjustment of an alluvial channel to in-stream and riparian vegetation using a distorted Froude-scale flume model with a movable boundary. A decimeter-scale trapezoidal channel comprised of 0.8-mm diameter sand was systematically vegetated with emergent, rigid dowels (3-mm in diameter) in rectangular and hemispherical patterns with varying vegetation densities while conserving the shape of the zone and the geometry of the vegetal patterns. Alternate sides of the channel were vegetated at the prescribed spacing of equilibrium alternate bars, ca. 5 to 7 times the channel width. Using flow conditions just below the threshold of sediment motion, flow obstruction, deflection, and acceleration caused bed erosion, bank failure, and morphologic channel adjustments that were wholly attributable to the managed plantings. As vegetation density increased, the magnitude and rate of scaled channel adjustment increased, which included increased channel widths, bankline steepening and meandering, and thalweg meandering. As the modeled channel began to meander, the stream bed aggraded and flow depth decreased markedly, creating a continuously connected, inter-reach complex of mid-channel bars. This study demonstrates the utility of using managed vegetations in stream corridor design and meander development, and it provides the practitioner with guidance on the magnitude of channel adjustment as it relates to vegetation density, shape, and spacing.

A spatially distributed model for the assessment of land use impacts on stream temperature in small urban watersheds

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

Sun, Ning; Yearsley, John; Voisin, Nathalie

2015-05-15

Stream temperatures in urban watersheds are influenced to a high degree by anthropogenic impacts related to changes in landscape, stream channel morphology, and climate. These impacts can occur at small time and length scales, hence require analytical tools that consider the influence of the hydrologic regime, energy fluxes, topography, channel morphology, and near-stream vegetation distribution. Here we describe a modeling system that integrates the Distributed Hydrologic Soil Vegetation Model, DHSVM, with the semi-Lagrangian stream temperature model RBM, which has the capability to simulate the hydrology and water temperature of urban streams at high time and space resolutions, as well asmore » a representation of the effects of riparian shading on stream energetics. We demonstrate the modeling system through application to the Mercer Creek watershed, a small urban catchment near Bellevue, Washington. The results suggest that the model is able both to produce realistic streamflow predictions at fine temporal and spatial scales, and to provide spatially distributed water temperature predictions that are consistent with observations throughout a complex stream network. We use the modeling construct to characterize impacts of land use change and near-stream vegetation change on stream temperature throughout the Mercer Creek system. We then explore the sensitivity of stream temperature to land use changes and modifications in vegetation along the riparian corridor.« less

Evaluation plan for the I-95 CC ATIS (Corridor-TravTips) program

DOT National Transportation Integrated Search

1999-03-01

The Boston-to-New York travel corridor is one of the busiest travel corridors in the country and, typical of such developed areas, is experiencing congestion and safety problems and other travel-related inefficiencies along its transportation systems...

Pedestrian visual recommendation in Kertanegara - Semeru corridor in Malang City

NASA Astrophysics Data System (ADS)

Cosalia, V. B.

2017-06-01

Streetscape could be the first impression to see an urban area. One of the streerscape that should be attended to it is corridor of Jl. Kertanegara - Semeru since at that corridor is the road corridor having the strong caracter also as the one of the main axes in Malang city. This research is aim knowing the visual quality also the exact structuring rcommendation for Jl. Kertanegara - Semeru based on pedestrian’s visual. The methode used to this research is Scenic Beauty Estimation (SBE) and used historic study. There is several variables used, they are scale space, visual flexibility, beauty, emphasis, balance and dominant. Based on those variable the pedestrians as a respondent doing the assessment. Based on the result of SBE have been done, it is showed that the visual quality in Corridor Kertanegara Semeru is well enough since the result showed that there are 10 photos in low visual quality in Jl. Semeru and 14 photos in high visual quality in Jl. Kertanegara, Jl. Tugu dan Jl. Kahuripan. By the historic study and based on high visual quality reference doing the structuring recommendation in part of landscape having the low visual quality.

Discrete element method for emergency flow of pedestrian in S-type corridor.

PubMed

Song, Gyeongwon; Park, Junyoung

2014-10-01

Pedestrian flow in curved corridor should be modeled before design because this type of corridor can be most dangerous part during emergency evacuation. In this study, this flow is analyzed by Discrete Element Method with psychological effects. As the turning slope of corridor increases, the evacuation time is linearly increases. However, in the view of crashed death accident, the case with 90 degree turning slope can be dangerous because there are 3 dangerous points. To solve this matter, the pedestrian gathering together in curved part should be dispersed.

Identifying Corridors among Large Protected Areas in the United States

PubMed Central

Belote, R. Travis; Dietz, Matthew S.; McRae, Brad H.; Theobald, David M.; McClure, Meredith L.; Irwin, G. Hugh; McKinley, Peter S.; Gage, Josh A.; Aplet, Gregory H.

2016-01-01

Conservation scientists emphasize the importance of maintaining a connected network of protected areas to prevent ecosystems and populations from becoming isolated, reduce the risk of extinction, and ultimately sustain biodiversity. Keeping protected areas connected in a network is increasingly recognized as a conservation priority in the current era of rapid climate change. Models that identify suitable linkages between core areas have been used to prioritize potentially important corridors for maintaining functional connectivity. Here, we identify the most “natural” (i.e., least human-modified) corridors between large protected areas in the contiguous Unites States. We aggregated results from multiple connectivity models to develop a composite map of corridors reflecting agreement of models run under different assumptions about how human modification of land may influence connectivity. To identify which land units are most important for sustaining structural connectivity, we used the composite map of corridors to evaluate connectivity priorities in two ways: (1) among land units outside of our pool of large core protected areas and (2) among units administratively protected as Inventoried Roadless (IRAs) or Wilderness Study Areas (WSAs). Corridor values varied substantially among classes of “unprotected” non-core land units, and land units of high connectivity value and priority represent diverse ownerships and existing levels of protections. We provide a ranking of IRAs and WSAs that should be prioritized for additional protection to maintain minimal human modification. Our results provide a coarse-scale assessment of connectivity priorities for maintaining a connected network of protected areas. PMID:27104683

78 FR 32007 - Environmental Impact Statement for Tulsa-Oklahoma City Passenger Rail Corridor, Oklahoma, Lincoln...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-28

... Environmental Policy Act of 1969 (NEPA) for the State of Oklahoma High-Speed Rail Initiative: Tulsa--Oklahoma... South Central High Speed Rail Corridor and is a federally-designated high-speed rail (HSR) corridor...-Speed Rail Initiative: Tulsa--Oklahoma City Passenger Rail Corridor Investment Plan. The proposed route...

Landscape corridors can increase invasion by an exotic species and reduce diversity of native species.

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

Resasco, Julian; et al,

2014-04-01

Abstract. Landscape corridors are commonly used to mitigate negative effects of habitat fragmentation, but concerns persist that they may facilitate the spread of invasive species. In a replicated landscape experiment of open habitat, we measured effects of corridors on the invasive fire ant, Solenopsis invicta, and native ants. Fire ants have two social forms: polygyne, which tend to disperse poorly but establish at high densities, and monogyne, which disperse widely but establish at lower densities. In landscapes dominated by polygyne fire ants, fire ant abundance was higher and native ant diversity was lower in habitat patches connected by corridors thanmore » in unconnected patches. Conversely, in landscapes dominated by monogyne fire ants, connectivity had no influence on fire ant abundance and native ant diversity. Polygyne fire ants dominated recently created landscapes, suggesting that these corridor effects may be transient. Our results suggest that corridors can facilitate invasion and they highlight the importance of considering species’ traits when assessing corridor utility.« less

Integrated corridor management initiative : overview of the Dallas traveler response panel survey.

DOT National Transportation Integrated Search

2017-03-01

This report presents findings from the Integrated Corridor Management (ICM) traveler behavior surveys, a set of panel surveys of US-75 corridor users, conducted before and after the deployment of ICM. The purpose of the surveys was to measure the imp...

The EmX Franklin Corridor BRT project evaluation : final report, April 2009.

DOT National Transportation Integrated Search

2009-04-01

Lane Transit District began BRT service on its Franklin Corridor EmX in January 14, 2007. The four mile long route connects downtown Eugene and downtown Springfield, the two main hubs for LTDs system. The corridor, which has the greatest ridership...

Effects of stream topology on ecological community results from neutral models

EPA Science Inventory

While neutral theory and models have stimulated considerable literature, less well investigated is the effect of topology on neutral metacommunity model simulations. We implemented a neutral metacommunity model using two different stream network topologies, a widely branched netw...

Northeast Corridor Travel Survey : 1968-1971

DOT National Transportation Integrated Search

1974-01-01

The Northeast Corridor Travel Survey was conducted by the U.S. Census Bureau for the Federal Railroad Administration to determine the impact of High Speed Rail Demonstration Projects operated between Washington-New York and New York-Boston. This repo...

Spatial ecology of predator-prey interactions: corridors and patch shape influence seed predation.

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

J. L . Orrock; B. J. Danielson; M. J. Burns

2003-02-03

J.L. Orrock, B.J. Danielson, M.J. Burns, and D.J. Levey. 2003. Spatial ecology of predator-prey interactions: corridors and patch shape influence seed predation. Ecology, 84(10):2589-2599. Abstract: Corridors that connect patches of disjunct habitat may be promising tools for mediating the negative impacts of habitat fragmentation, but little is known about how corridors affect ecological interactions. In eight 12-ha experimental landscapes, we examined how corridors affect the impact of invertebrate, rodent, and avian seed predators on pokeweed, Phytolacca americana. Over 13 months in 2000 and 2001, we quantified the effects of patch shape, connectivity, and predator type on the number of seedsmore » germinating in the field (germinants), seed removal, and the viability of remaining seeds. Corridors did not affect the number of P. americana germinants in experimental exclosures or the viability of seeds remaining in exclosures. However, corridors affected the removal of seeds in a predator-specific manner: invertebrates removed more seeds in unconnected patches, whereas rodents removed more seeds in connected patches. Seed removal by birds was similar in connected and unconnected patches. Total seed removal by all seed predators was not affected by corridors, because invertebrates removed more seeds where rodents removed fewer seeds, and vice versa. Overall, seed predation signi®cantly reduced the number and viability of remaining seeds, and reduced the number of germinants in 2000 but not in 2001. The abundance of naturally occurring P. americana plants in our experimental patches in 2000 decreased with increasing seed removal from exclosures but was not related to viability or germinants in 2000, suggesting that seed removal may shape the distribution and abundance of this species. Complementary patterns of seed removal by rodents and invertebrates suggest that corridors alter the effects of these predator taxa by changing the relative amounts of edge and

Chapter 1: Hydrologic exchange flows and their ecological consequences in river corridors

USGS Publications Warehouse

Harvey, Judson

2016-01-01

The actively flowing waters of streams and rivers remain in close contact with surrounding off-channel and subsurface environments. These hydrologic linkages between relatively fast flowing channel waters, with more slowly flowing waters off-channel and in the subsurface, are collectively referred to as hydrologic exchange flows (HEFs). HEFs include surface exchange with a channel’s marginal areas and subsurface flow through the streambed (hyporheic flow), as well as storm-driven bank storage and overbank flows onto floodplains. HEFs are important, not only for storing water and attenuating flood peaks, but also for their role in influencing water conservation, water quality improvement, and related outcomes for ecological values and services of aquatic ecosystems. Biogeochemical opportunities for chemical transformations are increased by HEFs as a result of the prolonged contact between flowing waters and geochemically and microbially active surfaces of sediments and vegetation. Chemical processing is intensified and water quality is often improved by removal of excess nutrients, metals, and organic contaminants from flowing waters. HEFs also are important regulators of organic matter decomposition, nutrient recycling, and stream metabolism that helps establish a balanced and resilient aquatic food web. The shallow and protected storage zones associated with HEFs support nursery and feeding areas for aquatic organisms that sustain aquatic biological diversity. Understanding of these varied roles for HEFs has been driven by the related disciplines of stream ecology, fluvial geomorphology, surface-water hydraulics, and groundwater hydrology. A current research emphasis is on the role that HEFs play in altered flow regimes, including restoration to achieve diverse goals, such as expanding aquatic habitats and managing dissolved and suspended river loads to reduce over-fertilization of coastal waters and offset wetland loss. New integrative concepts and models are

Angeles National Forest Transit Corridor Analysis

DOT National Transportation Integrated Search

2018-04-01

This report provides analysis of three corridors connecting the Gold Line in the Los Angeles metropolitan area to high use recreation sites on the Angeles National Forest. The high use recreation sites pose congestion and safety issues, as visitors p...

Effects of weighting schemes on the identification of wildlife corridors generated with least-cost methods

Treesearch

Sean A. Parks; Kevin S. McKelvey; Michael K. Schwartz

2012-01-01

The importance of movement corridors for maintaining connectivity within metapopulations of wild animals is a cornerstone of conservation. One common approach for determining corridor locations is least-cost corridor (LCC) modeling, which uses algorithms within a geographic information system to search for routes with the lowest cumulative resistance between target...

"Everything Happens in the Hallways": Exploring User Activity in the Corridors at Two Rehabilitation Units.

PubMed

Colley, Jacinta; Zeeman, Heidi; Kendall, Elizabeth

2017-01-01

This research aimed to examine the role of the corridors in specialist inpatient rehabilitation units to inform future design of these spaces. In healthcare settings, such as rehabilitation units, corridors have often been designed simply as spaces allowing movement between other locations. However, research suggests that corridors may be places where important social and care-related activities take place. How corridors are used and understood by patients and staff in inpatient rehabilitation settings is unclear, and a greater understanding of the role of corridors in these settings could help to inform more supportive design of these spaces. Independent observations of user activity were conducted at a major metropolitan inpatient spinal injury unit (SIU) and brain injury unit (BIU). Interviews were conducted with SIU patients ( n = 12), and focus groups were conducted with SIU staff ( n = 23), BIU patients ( n = 12), and BIU staff ( n = 10). Results from the observations showed that the corridors were used frequently across the day, particularly by staff. Thematic analysis of staff and patient experiences found three key themes describing how corridors were used: (1) moving around, (2) delivery and experiences of quality care, and (3) a "spillover space." Results demonstrate that corridors not only have an important role as connective spaces but are also used as flexible, multipurpose spaces for delivery of quality care and patient experiences. Future design should consider how these spaces can more deliberately support and contribute to patient and staff experiences of rehabilitation.

INTERIM RESULTS FROM A STUDY OF THE IMPACTS OF TIN(II) BASED MERCURY TREATMENT IN A SMALL STREAM ECOSYSTEM: TIMS BRANCH, SAVANNAH RIVER SITE

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

Looney, B.; Bryan, L.; Mathews, T.

2012-03-30

source control measures have resulted in rapid responses in lake or reservoir fisheries (Joslin 1994, Turner and Southworth 1999; Orihel et al., 2007), but examples of similar responses in Hg-contaminated stream ecosystems are less common. Recent work suggests that stream systems may actually be more susceptible to mercury bioaccumulation than lakes, highlighting the need to better understand the ecological drivers of mercury bioaccumulation in stream-dwelling fish (Chasar et al. 2009, Ward et al. 2010). In the present study we examine the response of fish to remedial actions in Tims Branch, a point-source contaminated stream on the Department of Energy's (DOE) Savannah River Site in Aiken, South Carolina. This second order stream received inorganic mercury inputs at its headwaters from the 1950s-2000s which contaminated the water, sediments, and biota downstream. In 2007, an innovative mercury removal system using tin (II) chloride (stannous chloride, SnCl{sub 2}) was implemented at a pre-existing air stripper. Tin(II) reduces dissolved Hg (II) to Hg (0), which is removed by the air stripper. During this process, tin(II) is oxidized to tin (IV) which is expected to precipitate as colloidal tin(IV) oxides and hydroxides, particulate materials with relatively low toxicity (Hallas and Cooney, 1981, EPA 2002, ATSDR, 2005). The objectives of the present research are to provide an initial assessment of the net impacts of the tin(II) based mercury treatment on key biota and to document the distribution and fate of inorganic tin in this small stream ecosystem after the first several years of operating a full scale system. To support these objectives, we collected fish, sediment, water, invertebrates, and biofilm samples from Tims Branch to quantify the general behavior and accumulation patterns for mercury and tin in the ecosystem and to determine if the treatment process has resulted in: (1) a measurable beneficial impact on (i.e., decrease of) mercury concentration in upper

Integrated corridor management concept development and foundational research. Task 3.2, develop criteria for delineating a corridor

DOT National Transportation Integrated Search

2006-04-12

Task 3 involves overall foundational research to further the understanding of various aspects of Integrated Corridor Management (ICM) and to identify integration issues needed to evaluate the feasibility of the ICM initiative. The focus of Task 3.2 a...

Traffic analysis toolbox volume XIII : integrated corridor management analysis, modeling, and simulation guide

DOT National Transportation Integrated Search

2017-02-01

As part of the Federal Highway Administration (FHWA) Traffic Analysis Toolbox (Volume XIII), this guide was designed to help corridor stakeholders implement the Integrated Corridor Management (ICM) Analysis, Modeling, and Simulation (AMS) methodology...

Traffic analysis toolbox volume XIII : integrated corridor management analysis, modeling, and simulation guide.

DOT National Transportation Integrated Search

2017-02-01

As part of the Federal Highway Administration (FHWA) Traffic Analysis Toolbox (Volume XIII), this guide was designed to help corridor stakeholders implement the Integrated Corridor Management (ICM) Analysis, Modeling, and Simulation (AMS) methodology...

Oceanic Situational Awareness Over the Pacific Corridor

NASA Technical Reports Server (NTRS)

Welch, Bryan; Greenfeld, Israel

2005-01-01

Air traffic control (ATC) mandated, aircraft separations over the oceans impose a limitation on traffic capacity for a given corridor, given the projected traffic growth over the Pacific Ocean. The separations result from a lack of acceptable situational awareness over oceans where radar position updates are not available. This study considers the use of Automatic Dependent Surveillance (ADS) data transmitted over a commercial satellite communications system as an approach to provide ATC with the needed situational awareness and thusly allow for reduced aircraft separations. This study uses Federal Aviation Administration data from a single day for the Pacific Corridor to analyze traffic loading to be used as a benchmark against which to compare several approaches for coordinating data transmissions from the aircraft to the satellites.

WASP7 Stream Transport - Model Theory and User's Guide: Supplement to Water Quality Analysis Simulation Program (WASP) User Documentation

EPA Science Inventory

The standard WASP7 stream transport model calculates water flow through a branching stream network that may include both free-flowing and ponded segments. This supplemental user manual documents the hydraulic algorithms, including the transport and hydrogeometry equations, the m...

77 FR 55265 - Environmental Impact Statement for the Northeast Corridor Between Washington, DC, New York, NY...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-07

... the Northeast Corridor Between Washington, DC, New York, NY, and Boston, MA AGENCY: Federal Railroad... ). SUPPLEMENTARY INFORMATION: FRA is leading the planning and environmental evaluation of the Northeast Corridor (NEC) in close coordination with the involved states, Northeast Corridor Infrastructure and Operations...

Mapping Milky Way Halo Structure with Blue Horizontal Branch Stars

NASA Astrophysics Data System (ADS)

Martin, Charles; Newberg, Heidi Jo; Carlin, Jeffrey L.

2017-01-01

The use of blue horizontal brach (BHB) and red giant branch stars as tracers of stellar debris streams is a common practice and has been useful in the confirmation of kinematic properties of previously identified streams. This work explores less common ways of untangling the velocity signatures of streams traveling radially to our line of sight, and to peer toward the higher density region of the Galactic Center using data from the Sloan Digital Sky Survey (SDSS). Using spectra of BHB stars, we are able to kinematically distinguish moving groups in the Milky Way halo. The results of this thesis advance our knowledge of the following stellar halo substructures: the Pisces Stellar Stream, the Hercules-Aquila Cloud, the Hercules Halo Stream, and the Hermus Stream. A study of red giant stars led to the kinematic discovery of the Pisces Stellar Stream. Red giant stars were also examined to determine that the previously identified velocity signature that was suggested for the Hercules-Aquila Cloud was due to disk star contamination and errors in preliminary SDSS velocities. The Hercules Halo Stream is a previously unidentified structure that could be related to the Hercules-Aquila Cloud, and was discovered as a velocity excess of SDSS BHB stars. We identify a group of 10 stars with similar velocities that are spatially coincident with the Hermus Stream. An orbit is fit to the Hermus Stream that rules out a connection with the Phoenix Stream.This work was supported by NSF grants AST 09-37523, 14-09421, 16-15688, the NASA/NY Space Grant fellowship, and contributions made by The Marvin Clan, Babette Josephs, Manit Limlamai, and the 2015 Crowd Funding Campaign to Support Milky Way Research.

Safe corridors for K-wiring in phalangeal fractures.

PubMed

Rex, C; Vignesh, R; Javed, M; Balaji, Subba Chandra; Premanand, C; Zakki, Syed Ashfaque

2015-01-01

Unstable phalangeal fractures are commonly treated with K-wire fixation. Operative fixation must be used judiciously and with the expectation that the ultimate outcome should be better than the outcome after nonoperative management. It is necessary to achieve a stable fracture fixation and early mobilization. In order to achieve this goal, one should closely understand the safe portals/corridors in hand for K-wire entry for fractures of the phalanges. Safe corridors were defined and tested using a pilot cadaveric and a clinical case study by assessing the outcome. In our prospective case series, 50 patients with 64 phalangeal fractures were treated with closed reduction and K-wires were inserted through safe portals identified by a pilot cadaveric study. On table active finger movement test was done and the results were analyed using radiology, disabilities of the arm, shoulder, and hand (DASH) score and total active motion (TAM). In our study, little finger (n = 28) was the most commonly involved digit. In fracture pattern, transverse (n = 20) and spiral (n = 20) types were common. Proximal phalanx (n = 38) was commonly involved and the common site being the base of the phalanx (n = 28). 47 (95%) patients had excellent TAM and the mean postoperative DASH score was 58.05. All patients achieved excellent and good scores proving the importance of the safe corridor concept. K-wiring through the safe corridor has proved to yield the best clinical results because of least tethering of soft tissues as evidenced by performing "on-table active finger movement test" at the time of surgery. We strongly recommend K-wiring through safe portals in all phalangeal fractures.

PEL and Corridor Planning: State of the Practice Review of Planning and Environment Linkages Implementation in Corridor Planning

DOT National Transportation Integrated Search

2014-07-01

The Federal Highway Administration (FHWA) commissioned a review of transportation corridor plans to determine the extent to which these plans have utilized FHWA's Planning and Environment Linkages (PEL) approach, as described in the FHWA Guidance on ...

Integrated corridor management : implementation guide and lessons learned (final report version 2.0).

DOT National Transportation Integrated Search

2015-09-01

This implementation guide is intended for use by adopters of integrated corridor management (ICM) approaches and strategies to address congestion and travel time reliability issues within specific travel corridors. It introduces the topic of ICM and ...

Calibrated models as management tools for stream-aquifer systems: the case of central Kansas, USA

NASA Astrophysics Data System (ADS)

Sophocleous, Marios; Perkins, Samuel P.

1993-12-01

We address the problem of declining streamflows in interconnected stream-aquifer systems and explore possible management options to address the problem for two areas of central Kansas: the Arkansas River valley from Kinsley to Great Bend and the lower Rattlesnake Creek-Quivira National Wildlife Refuge area. The approach we followed implements, calibrates, and partially validates for the study areas a stream-aquifer numerical model combined with a parameter estimation package and sensitivity analysis. Hydrologic budgets for both predevelopment and developed conditions indicate significant differences in the hydrologic components of the study areas resulting from development. The predevelopment water budgets give an estimate of natural ground-water recharge, whereas the budgets for developed conditions give an estimate of induced recharge, indicating that major ground-water development changes the recharge-discharge regime of the model areas with time. Such stream-aquifer models serve to link proposed actions to hydrologic effects, as is clearly demonstrated by the effects of various management alternatives on the streamflows of the Arkansas River and Rattlesnake Creek. Thus we show that a possible means of restoring specified streamflows in the area is to implement protective stream corridors with restricted ground-water extraction.

Calibrated models as management tools for stream-aquifer systems: the case of central Kansas, USA

USGS Publications Warehouse

Sophocleous, M.; Perkins, S.P.

1993-01-01

We address the problem of declining streamflows in interconnected stream-aquifer systems and explore possible management options to address the problem for two areas of central Kansas: the Arkansas River valley from Kinsley to Great Bend and the lower Rattlesnake Creek-Quivira National Wildlife Refuge area. The approach we followed implements, calibrates, and partially validates for the study areas a stream-aquifer numerical model combined with a parameter estimation package and sensitivity analysis. Hydrologic budgets for both predevelopment and developed conditions indicate significant differences in the hydrologic components of the study areas resulting from development. The predevelopment water budgets give an estimate of natural ground-water recharge, whereas the budgets for developed conditions give an estimate of induced recharge, indicating that major ground-water development changes the recharge-discharge regime of the model areas with time. Such stream-aquifer models serve to link proposed actions to hydrologic effects, as is clearly demonstrated by the effects of various management alternatives on the streamflows of the Arkansas River and Rattlesnake Creek. Thus we show that a possible means of restoring specified streamflows in the area is to implement protective stream corridors with restricted ground-water extraction. ?? 1993.

The Pen Branch Project: Restoration of a Forested Wetland in South Carolina

Treesearch

Randall K. Kolka; Eric A. Nelson; Ronald E. Bonar; Neil C. Dulohery; David Gartner

1998-01-01

The Pen Branch Project is a program to restore a forested riparian wetland that has been subject to thermal disturbance caused by nuclear reactor operations at the Department of Energy's (DOE) Savannah River Site (SRS), an 80,200-hectare nuclear facility located in South Carolina. Various levels of thermal discharges to streams located across the US. have occurred...

A biomimetic vision-based hovercraft accounts for bees' complex behaviour in various corridors.

PubMed

Roubieu, Frédéric L; Serres, Julien R; Colonnier, Fabien; Franceschini, Nicolas; Viollet, Stéphane; Ruffier, Franck

2014-09-01

Here we present the first systematic comparison between the visual guidance behaviour of a biomimetic robot and those of honeybees flying in similar environments. We built a miniature hovercraft which can travel safely along corridors with various configurations. For the first time, we implemented on a real physical robot the 'lateral optic flow regulation autopilot', which we previously studied computer simulations. This autopilot inspired by the results of experiments on various species of hymenoptera consists of two intertwined feedback loops, the speed and lateral control loops, each of which has its own optic flow (OF) set-point. A heading-lock system makes the robot move straight ahead as fast as 69 cm s(-1) with a clearance from one wall as small as 31 cm, giving an unusually high translational OF value (125° s(-1)). Our biomimetic robot was found to navigate safely along straight, tapered and bent corridors, and to react appropriately to perturbations such as the lack of texture on one wall, the presence of a tapering or non-stationary section of the corridor and even a sloping terrain equivalent to a wind disturbance. The front end of the visual system consists of only two local motion sensors (LMS), one on each side. This minimalistic visual system measuring the lateral OF suffices to control both the robot's forward speed and its clearance from the walls without ever measuring any speeds or distances. We added two additional LMSs oriented at +/-45° to improve the robot's performances in stiffly tapered corridors. The simple control system accounts for worker bees' ability to navigate safely in six challenging environments: straight corridors, single walls, tapered corridors, straight corridors with part of one wall moving or missing, as well as in the presence of wind.

US-75 ICM system design document : Dallas Integrated Corridor Management (ICM) demonstration project.

DOT National Transportation Integrated Search

2013-06-01

This System Design document for the US-75 Integrated Corridor Management (ICM) Program has been developed as part of the US Department of Transportation Integrated Corridor Management Initiative. The basic premise behind the ICM initiative is that in...

Nitrification in four acidic streams in southern New Jersey

USGS Publications Warehouse

Schornick, James C.; Ram, Neil M.

1978-01-01

Four characteristically acidic streams in southern New Jersey were investigated to determine the effect of secondary effluent on nitrification in the receiving waters. Chemical and microbiological data were obtained at four sites on each stream. From these data seven factors were evaluated to determine the proclivity of each stream to nitrify. pH, water temperature, and dissolved oxygen were used to describe the general condition of the streams, while neutralization of alkalinity, nitrogen species concentration trends, biological and nitrogenous oxygen demand incubations, and nitrifying bacteria densities were used to determine the actual presence of nitrification in each stream. Each stream had a unique distribution of conditions, making it possible to qualitatively rank the streams according to their proclivity to nitrify. Hay StackBrook showes strong evidence for nitrification on the basis of all four nitrification indicators, whereas Landing Creek showed little, if any, evidence of nitrification. Hammonton Creek is apparently nitrifying, but because of the uncertainty in the downstream trends of the nitrogen species and a lower level of alkalinity neutralization, it is nitrifying less than Hay Stack Brook. Squankum Branch also showed some evidence for nitrification, mostly on the basis of the biological and nitrogenous oxygen demand incubations. Although these streams are acidic in character, acidity does not appear to be an exclusive factor in determining whether a stream will undergo nitrification. (Woodard-USGS)

Objective and subjective evaluation of a redesigned corridor environment in a psychiatric hospital.

PubMed

Edgerton, Edward; Ritchie, Louise; McKechnie, Jim

2010-05-01

This study examined the impact of redesigning a corridor space within a psychiatric hospital on the behaviour of patients with dementia. In addition, patient and staff perceptions of the redesigned corridor were assessed. Data were collected through an observational tool (behavioural mapping) and a specifically design questionnaire. The findings suggest a positive impact of the redesigned corridor on patient behaviour and that patients and staff perceived the change to the environment differentially. These results are discussed in relation to theoretical explanations of the importance of the health care environment and design for dementia.

36 CFR 13.1108 - Alsek Corridor.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Alsek Corridor. 13.1108 Section 13.1108 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve...

36 CFR 13.1108 - Alsek Corridor.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Alsek Corridor. 13.1108 Section 13.1108 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve...

Mapping High Biomass Corridors for Climate and Biodiversity Co-Benefits

NASA Astrophysics Data System (ADS)

Jantz, P.; Goetz, S. J.; Laporte, N. T.

2013-12-01

A key issue in global conservation is how climate mitigation activities can secure biodiversity co-benefits. Tropical deforestation releases significant amounts of CO2 to the atmosphere and results in widespread biodiversity loss. The dominant strategy for forest conservation has been protected area designation. However, maintaining biodiversity in protected areas requires ecological exchange with ecosystems in which they are embedded. At current funding levels, existing conservation strategies are unlikely to prevent further loss of connectivity between protected areas and surrounding landscapes. The emergence of REDD+, a mechanism for funding carbon emissions reductions from deforestation in developing countries, suggests an alignment of goals and financial resources for protecting forest carbon, maintaining biodiversity in protected areas, and minimizing loss of forest ecosystem services. Identifying, protecting and sustainably managing vegetation carbon stocks between protected areas can provide both climate mitigation benefits through avoided CO2 emissions from deforestation and biodiversity benefits through the targeted protection of forests that maintain connectivity between protected areas and surrounding ecosystems. We used a high resolution, pan-tropical map of vegetation carbon stocks derived from MODIS, GLAS lidar and field measurements to map corridors that traverse areas of highest aboveground biomass between protected areas. We mapped over 13,000 corridors containing 49 GtC, accounting for 14% of unprotected vegetation carbon stock in the tropics. In the majority of cases, carbon density in corridors was commensurate with that of the protected areas they connect, suggesting significant opportunities for achieving climate mitigation and biodiversity co-benefits. To further illustrate the utility of this approach, we conducted a multi-criteria analysis of corridors in the Brazilian Amazon, identifying high biodiversity, high vegetation carbon stock

Integrated corridor management, concept development and foundational research. Task 3.3, relationship between corridor management and regional management

DOT National Transportation Integrated Search

2006-04-12

Task 3 involves overall foundational research to further the understanding of various aspects of Integrated Corridor Management (ICM) and to identify integration issues needed to evaluate the feasibility of the ICM initiative. The focus of Task 3.3 a...

A bee in the corridor: centering and wall-following

NASA Astrophysics Data System (ADS)

Serres, Julien R.; Masson, Guillaume P.; Ruffier, Franck; Franceschini, Nicolas

2008-12-01

In an attempt to better understand the mechanism underlying lateral collision avoidance in flying insects, we trained honeybees ( Apis mellifera) to fly through a large (95-cm wide) flight tunnel. We found that, depending on the entrance and feeder positions, honeybees would either center along the corridor midline or fly along one wall. Bees kept following one wall even when a major (150-cm long) part of the opposite wall was removed. These findings cannot be accounted for by the “optic flow balance” hypothesis that has been put forward to explain the typical bees’ “centering response” observed in narrower corridors. Both centering and wall-following behaviors are well accounted for, however, by a control scheme called the lateral optic flow regulator, i.e., a feedback system that strives to maintain the unilateral optic flow constant. The power of this control scheme is that it would allow the bee to guide itself visually in a corridor without having to measure its speed or distance from the walls.

Potential interaction between transport and stream networks over the lowland rivers in Eastern India.

PubMed

Roy, Suvendu; Sahu, Abhay Sankar

2017-07-15

Extension of transport networks supports good accessibility and associated with the development of a region. However, transport lines have fragmented the regional landscape and disturbed the natural interplay between rivers and their floodplains. Spatial analysis using multiple buffers provides information about the potential interaction between road and stream networks and their impact on channel morphology of a small watershed in the Lower Gangetic Plain. Present study is tried to understand the lateral and longitudinal disconnection in headwater stream by rural roads with the integration of geoinformatics and field survey. Significant (p < 0.001) growth of total road length and number of road-stream crossing in the last five decades (1970s-2010s) contribute to making longitudinal and lateral disconnection in the fluvial system of Kunur River Basin. Channel geometry from ten road-stream crossings shows significant (p = 0.01) differences between upstream and downstream of crossing structure and created problems like downstream scouring, increased drop height at outlet, formation of stable bars, severe bank erosion, and make barriers for river biota. The hydro-geomorphic processes are also adversely affected due to lateral disconnection and input of fine to coarse sediments from the river side growth of unpaved road (1922%). Limited streamside development, delineation of stream corridor, regular monitoring and engineering efficiency for the construction of road and road-stream crossing might be effective in managing river geomorphology and riverine landscape. Copyright © 2017 Elsevier Ltd. All rights reserved.

75 FR 45695 - Final Federal Agency Actions on Trans-Texas Corridor 35 (TTC-35) in Texas

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-03

...-Texas Corridor 35 (TTC-35) in Texas AGENCY: Federal Highway Administration (FHWA), DOT. ACTION: Notice...-modal corridor to meet the transportation challenges of the I-35 corridor. EIS No. 20100133. The actions.... Land: Section 4(f) of the Department of Transportation Act of 1966 [49 U.S.C. 303]. 4. Wildlife...

Integrated corridor traffic management : final evaluation report

DOT National Transportation Integrated Search

2000-04-01

In 1993, the Minnesota Department of Transportation (Mn/DOT) forged a partnership with Hennepin County and the cities of Bloomington Richfield, and Edina to test the concept of integrated corridor traffic management (ICTM) across jurisdictional bound...

Truck Parking Initiative : I-95 Corridor Coalition

DOT National Transportation Integrated Search

2008-02-14

The I-95 Corridor Coalition is very pleased to submit this application for funding, through the Maryland State Highway Administration, under the Federal Highway Administration's (FHWA) Truck Parking Initiative. The Coalition is an alliance of transpo...

Evolution of the landscape along the Clear Creek Corridor, Colorado; urbanization, aggregate mining and reclamation

USGS Publications Warehouse

Arbogast, Belinda; Knepper, Daniel H.; Melick, Roger A.; Hickman, John

2002-01-01

Prime agricultural land along the Clear Creek floodplain, Colorado, attracted settlement in the 1850's but the demand for sand and gravel for 1900's construction initiated a sequence of events that exceeded previous interests and created the modified landscape and urban ecosystem that exists today. The Clear Creek valley corridor offers a landscape filled with a persistent visible and hidden reminder of it's past use. The map sheets illustrate the Clear Creek landscape as a series of compositions, both at the macro view (in the spatial context of urban structure and highways from aerial photographs) and micro view (from the civic scale where landscape features like trees, buildings, and sidewalks are included). The large-scale topographic features, such as mountains and terraces, appear 'changeless' (they do change over geologic time), while Clear Creek has changed from a wide braided stream to a narrow confined stream. Transportation networks (streets and highways) and spiraling population growth in adjacent cities (from approximately 38,000 people in 1880 to over a million in 1999) form two dominant landscape patterns. Mining and wetland/riparian occupy the smallest amount of land use acres compared to urban, transportation, or water reservoir activities in the Clear Creek aggregate reserve study area. Four types of reclaimed pits along Clear Creek were determined: water storage facilities, wildlife/greenbelt space, multiple-purpose reservoirs, and 'hidden scenery.' The latter involves infilling gravel pits (with earth backfill, concrete rubble, or sanitary landfill) and covering the site with light industry or residential housing making the landform hard to detect as a past mine site. Easier to recognize are the strong-edged, rectilinear water reservoirs, reclaimed from off-channel sand and gravel pits that reflect the land survey grid and property boundaries. The general public may not realize softly contoured linear wildlife corridors connecting urban

Influence of Smile Arc and Buccal Corridors on Facial Attractiveness: A Cross-sectional Study

PubMed Central

Gaikwad, Shashank; Vaz, Anna C; Singh, Baldeep; Taneja, Lavina; Vinod, KS; Verma, Prateek

2016-01-01

Introduction Two aspects of the smile: the Smile Arc (SA) and Buccal Corridors (BC) have been the interest of the orthodontist in recent years. Aim The present study was undertaken to evaluate the influence of the smile arc and buccal corridors on facial attractiveness as evaluated by orthodontists, general dentists and laymen. Materials and Methods Two subjects (one male & one female) were selected from the regional population fulfilling the criteria of an ideal smile arc and ideal buccal corridors. Frontal smile view photographs of these subjects were taken and modified by using adobe photoshop 7.0 to create combination of three smile arc variance and three buccal corridors variations respectively which were shown to 25 orthodontists, 25 general dentists & 25 laymen, to rate the facial attractiveness of each image on a rating scale. Results All the three groups (laypersons, dentists and orthodontists) showed significant difference in ratings, indicating that they had different perceptions on the facial attractiveness. Conclusion Orthodontists were more precise in discerning the smile arc and buccal corridors compared to dentists and laypersons. PMID:27790573

Maxillary arch width and buccal corridor changes with Damon and conventional brackets: A retrospective analysis.

PubMed

Shook, Corey; Kim, Sohyon Michelle; Burnheimer, John

2016-07-01

To evaluate the effect of Damon self-ligating and conventional bracket systems on buccal corridor widths and areas. A retrospective sample of consecutively treated patients using either conventional (CG, n  =  45) or Damon self-ligating (SL, n  =  39) brackets was analyzed to determine any differences in buccal corridor widths and areas both within and between groups. Pretreatment and posttreatment frontal photographs were transferred to Photoshop CC, standardized using intercanthal width, and linear and area measurements were performed with tools in Photoshop CC. Ratios were then calculated for statistical analysis. Relationships between arch widths and buccal corridors were also examined. There were no significant differences in the posttreatment intercanine or intermolar widths either within or between the CG and SL groups. There were no significant differences in any buccal corridor width or area measurement either within or between the CG and SL groups. There were strong correlations with the intercanine width and the corresponding buccal corridor smile width measurements. There was an inverse correlation with the buccal corridor area in relation to the canine and the total smile width. It is likely that posttreatment increases in arch width can be seen in patients treated with either a conventional bracket system or the Damon system. It is highly unlikely that there is any significant difference in buccal corridor width or area in patients treated with the Damon self-ligating system or a conventional bracket system.

Silicon Valley Smart Corridor : draft evaluation strategy

DOT National Transportation Integrated Search

2000-06-05

This document outlines the strategy for evaluating the integrated freeway, arterial, and incident management system known as the Silicon Valley Smart Corridor (SVSC). Centered in San Jose, California, the SVSC is one of approximately 65 deployments o...

Use of empirically derived source-destination models to map regional conservation corridors

Treesearch

Samuel A. Cushman; Kevin S. McKelvey; Michael K. Schwartz

2008-01-01

The ability of populations to be connected across large landscapes via dispersal is critical to longterm viability for many species. One means to mitigate population isolation is the protection of movement corridors among habitat patches. Nevertheless, the utility of small, narrow, linear features as habitat corridors has been hotly debated. Here, we argue that...

Northwest Montana/North Idaho transmission corridor study: a computer-assisted corridor location and impact evaluation assessment

Treesearch

Timothy J. Murray; Daniel J. Bisenius; Jay G. Marcotte

1979-01-01

A computer-assisted method was used to locate and evaluate approximately 1,200 miles of alternative corridors within an 8,000 square mile study region. The method involved in-depth impact analyses for nine major location criteria or determinant models. Regional "experts" from the Rocky Mountain area participated with BPA in developing model structure....

Water quality of streams in the Neshaminy Creek basin, Pennsylvania

USGS Publications Warehouse

McCarren, Edward F.

1972-01-01

The Neshaminy has carved a scenic route on its way to the Delaware River, thereby helping to increase the value of land. The unabated growth of nearby metropolitan areas and the multiplying needs for water and open space for water storage and recreation in southeastern Pennsylvania have become impelling forces that mark the Neshaminy valley watershed for continued development of its land and water resources. Toward this end the Neshaminy Valley Watershed Association, Inc., which came into existence June 13, 1956, is one of several organizations dedicated to land and water-resources development in the Neshaminy Creek basin. The principal objectives of the Neshaminy Valley Watershed Association are (1) to provide for future water-supply and recreation needs, (2) to safeguard against flood and drought damage, (3) to decrease stream pollution, (4) to preserve wildlife and natural beauty, (5) to reduce soil erosion and siltation, 96) to reforest marginal land, and (7) to improve and protect existing woodland. This study shows that there is a wide variance in water quality between the West Branch and the North Branch of the Neshaminy. However, the study shows no significant difference between the chemical composition of the Little Neshaminy Creek and the main stream before they come together at Rushland. Just beyond their confluence the main stream has drained more than half its total drainage area. The average flow of the stream at this location is about 85 percent of the average flow at Langhorne. The continued presence of game fish in most of Neshaminy Creek indicates a degree of water purity that characterizes this stream as suitable for recreation. However, during the summer and early fall, several small streams feeding the Neshaminy go dry. The diminished flow during these periods and during prolonged drought impairs stream quality by causing a greater concentration of dissolved solids in water. The relatively inferior water during low-flow periods, therefore

Earthquake hazards in the Alaska transportation corridors

DOT National Transportation Integrated Search

1983-03-01

Based on observations made by modern seismographic networks since 1967, and taking into consideration historical records of large Alaskan earthquakes in the past, it is judged that the hazards faced by transportation corridors in different areas of t...

Corridors of migrating neurons in the human brain and their decline during infancy.

PubMed

Sanai, Nader; Nguyen, Thuhien; Ihrie, Rebecca A; Mirzadeh, Zaman; Tsai, Hui-Hsin; Wong, Michael; Gupta, Nalin; Berger, Mitchel S; Huang, Eric; Garcia-Verdugo, Jose-Manuel; Rowitch, David H; Alvarez-Buylla, Arturo

2011-09-28

The subventricular zone of many adult non-human mammals generates large numbers of new neurons destined for the olfactory bulb. Along the walls of the lateral ventricles, immature neuronal progeny migrate in tangentially oriented chains that coalesce into a rostral migratory stream (RMS) connecting the subventricular zone to the olfactory bulb. The adult human subventricular zone, in contrast, contains a hypocellular gap layer separating the ependymal lining from a periventricular ribbon of astrocytes. Some of these subventricular zone astrocytes can function as neural stem cells in vitro, but their function in vivo remains controversial. An initial report found few subventricular zone proliferating cells and rare migrating immature neurons in the RMS of adult humans. In contrast, a subsequent study indicated robust proliferation and migration in the human subventricular zone and RMS. Here we find that the infant human subventricular zone and RMS contain an extensive corridor of migrating immature neurons before 18 months of age but, contrary to previous reports, this germinal activity subsides in older children and is nearly extinct by adulthood. Surprisingly, during this limited window of neurogenesis, not all new neurons in the human subventricular zone are destined for the olfactory bulb--we describe a major migratory pathway that targets the prefrontal cortex in humans. Together, these findings reveal robust streams of tangentially migrating immature neurons in human early postnatal subventricular zone and cortex. These pathways represent potential targets of neurological injuries affecting neonates.

CT scan based determination of optimal bone corridor for atlantoaxial ventral screw fixation in miniature breed dogs.

PubMed

Vizcaíno Revés, Núria; Stahl, Cristina; Stoffel, Michael; Bali, Monty; Forterre, Franck

2013-10-01

To describe the most reliable insertion angle, corridor length and width to place a ventral transarticular atlantoaxial screw in miniature breed dogs. Retrospective CT imaging study. Cervical CT scans of toy breed dogs (n = 21). Dogs were divided into 2 groups--group 1: no atlantoaxial abnormalities; group 2: atlantoaxial instability. Insertion angle in medial to lateral and ventral to dorsal direction was measured in group 1. Corridor length and width were measured in groups 1 and 2. Corridor width was measured at 3 points of the corridor. Each variable was measured 3 times and the mean used for statistical analysis. Mean ± SD optimal transarticular atlantoaxial insertion angle was determined to be 40 ± 1° in medial to lateral direction from the midline and 20 ± 1° in ventral to dorsal direction from the floor of the neural canal of C2. Mean corridor length was 7 mm (range, 4.5-8.0 mm). Significant correlation was found between corridor length, body weight, and age. Mean bone corridor width ranged from 3 to 5 mm. Statistically significant differences were found between individuals, gender and measured side. Optimal placement of a transarticular screw for atlantoaxial joint stabilization is very demanding because the screw path corridor is very narrow. © Copyright 2013 by The American College of Veterinary Surgeons.

Corridor connecting giant panda habitats from north to south in the Min Mountains, Sichuan, China.

PubMed

Yin, Kaipu; Xie, Yan; Wu, Ning

2006-12-01

The giant panda faces severe threats from habitat fragmentation and isolation. Currently, giant panda populations have been fragmented into 30 habitat patches. The disappearance of isolated small populations and studies on the genetic diversity of various populations have shown that small isolated panda populations are at a high risk of dying out completely. Habitat fragmentation has seriously impaired the ability of the giant panda to resist climate changes and other natural disasters, such as large-scale, synchronous bamboo blooming. The Min Mountains have the largest population of pandas in China, numbering 581 individuals and accounting for 52% of the total (1114) in China. Geographic isolation means that giant pandas in the Min Mountains are divided into two populations (population A in the north and population B in the south). Population B, which had only 42 individuals in 1989, is severely threatened by high-density human populations and the loss of genetic diversity. However, we have identified an important corridor connecting the two populations. This paper explains the importance and the feasibility of reestablishing this corridor. Due to the special geographic locations of these two populations (two rivers block the migration of giant pandas between south and north), the corridor is the only passage for giant pandas in the region. Recent studies have also shown an increase of giant panda activity in the area of the corridor. However, vegetation in the corridor has been severely degraded. Bamboo forest must be restored in this area to provide food for the pandas during migration. The effects of human activities must be reduced in order to maintain panda habitat. We believe that a restored corridor will be of great benefit to the survival of giant pandas in the Min Mountains, especially for population B. Successful re-establishment of a corridor will be a valuable model for corridor construction in the future.

Transportation policy and governance in the northeast corridor : an overview of major public agencies.

DOT National Transportation Integrated Search

2009-08-01

One of the most consistent topics of discussion about the Northeast Corridor (hereafter : NEC or the Corridor), particularly the central portion between Boston and Washington, : D.C., is the viability and efficiency of its transportation ...

Branching and resonant characteristics of surface plasma waves in a semi-bounded quantum plasma including spin-current effects

NASA Astrophysics Data System (ADS)

Lee, Myoung-Jae; Jung, Gwanyong; Jung, Young-Dae

2018-05-01

The dispersion relation for the waves propagating on the surface of a bounded quantum plasma with consideration of electron spin-current and ion-stream is derived and numerically investigated. We have found that one of the real parts of the wave frequency has the branching behavior beyond the instability domains. In such a region where the frequency branching occurs, the waves exhibit purely propagating mode. The resonant instability has also been investigated. We have found that when the phase velocity of the wave is close to the velocity of ion-stream the wave becomes unstable. However, the resonant growth rate is remarkably reduced by the effect of electron spin-current. The growth rate is also decreased by either the reduction of ion-stream velocity or the increase in quantum wavelength. Thus, the quantum effect in terms of the quantum wave number is found to suppress the resonant instability. It is also found that the increase in Fermi energy can reduce the growth rate of the resonant wave in the quantum plasma.

New insights into West Greenland ice sheet/stream dynamics during the last glacial cycle.

NASA Astrophysics Data System (ADS)

Roberts, David; Lane, Tim; Rea, Brice; Cofaigh, Colm O.; Jamieson, Stewart; Vieli, Andreas; Rodes, Angel

2015-04-01

Onshore and offshore geomorphological mapping and deglacial chronologies from West Greenland constrain the nature and magnitude of ice advance and decay of the Greenland Ice Sheet (GrIS) during the last glacial cycle. Several ice stream troughs are known to have fed ice to the shelf edge during the last glacial cycle. Their offshore expression suggests that many were coalescent systems fed by smaller outlet glaciers and ice streams onshore but their central flow pathways were also controlled by geology and preglacial topography. The bed morphology of these large ice streams shows they operated over soft, deforming beds with drumlins, mega-scale glacial lineations and grounding zone wedges marking an offshore transition from predominant areal scour onshore. Records of offshore deglacial chronology remain sparse but the Uummannaq and Disko Bugt ice stream corridors are now well constrained. The Uummannaq ice stream (UIS) completely deglaciated from the continental shelf between 14.8 ka and 11.0 ka in response to rising air temperatures, increasing JJA solar radiation and sea-level rise, but temporary standstills and the asynchronous retreat history of its feeder zones suggest that topography/bathymetry strongly modulated retreat rates as ice became 'locked' back into the coastal fjord system. Initial reconstructions of behaviour UIS discounted an oceanic role in early deglaciation and favoured retreat from the mid-shelf and inner-shelf prior to the Younger Dryas but both these concepts remain under investigation. In Disko Bugt, Jakobshavn Isbrae deglaciated later than the UIS and remained on the outer shelf during the Younger Dyras stadial (12.8 - 11.7 cal. kyrs BP) only reaching in the inner coast fjords at approximately 10.0 ka. The later deglaciation of the Disko system (despite similar external forcing mechanisms) was controlled by regional topographic/bathymetric contrasts in their respective trough morphologies. This hypothesis is supported by recent model

I-15 integrated corridor management : system requirements.

DOT National Transportation Integrated Search

2011-07-01

This document is intended as a listing and discussion of the Requirements for the I-15 Integrated Corridor Management System (ICMS) Demonstration Project in San Diego. This document describes what the system is to do (the functional requirements), ho...

Unionville, Pennsylvania School's Stream Restoration Project

NASA Astrophysics Data System (ADS)

Madsen, S. M.

2004-12-01

For the past three years, students and Earth Club members of C.F. Patton Middle School and Unionville High School have been involved in a stream restoration and monitoring project along a tributary to the East Branch of the Red Clay Creek in Pennsylvania. The Red Clay is within the larger Christina River Basin watershed which drains to Delaware Bay. Total funding of \\$962.00 was awarded by the Unionville-Chadds Ford Education Foundation to purchase both stream monitoring equipment and native plant species for stream restoration. Nine science teachers in the school district received certification in stream monitoring by the Pennsylvania State Parks Division. Certification enables the science faculty and their students to enter monitoring data in a statewide stream database. The stream data includes: temperature, levels of dissolved oxygen and nutrients, pH, alkalinity, conductivity, and a complete biosurvey of invertebrates. In addition to ongoing monitoring, the Earth Club sponsored a name-the-stream contest. Quartz Creek was chosen for this previously unnamed tributary. Its' name was approved by the East Marlborough Township Supervisor in May, 2004 and was then submitted to the USGS' Board on Geographic Names. The Earth Club has also sponsored a stream restoration contest. Students in the middle school were encouraged to design a habitat along the stream banks that would keep sediment in-place, while encouraging wildlife. The stream was originally crowded with invasive multi-flora rose but this was removed with the help of parents and students over a two year period. The winning student poster was outstanding and native species were purchased and planted following the poster's design. The planting took place in May, 2004 with over 40 persons involved including 25 middle school and 8 high school students, teachers from the schools, administrators and employees of the Brandywine Conservancy, and Red Clay Valley and Brandywine Valley Associations, and graduate

Geochemical variations in aeolian mineral particles from the Sahara-Sahel Dust Corridor.

PubMed

Moreno, Teresa; Querol, Xavier; Castillo, Sonia; Alastuey, Andrés; Cuevas, Emilio; Herrmann, Ludger; Mounkaila, Mohammed; Elvira, Josep; Gibbons, Wes

2006-10-01

The Sahara-Sahel Dust Corridor runs from Chad to Mauritania and expels huge amounts of mineral aerosols into the Atlantic Ocean. Data on samples collected from Algeria, Chad, Niger, and Western Sahara illustrate how corridor dust mineralogy and chemistry relate to geological source and weathering/transport history. Dusts sourced directly from igneous and metamorphic massifs are geochemically immature, retaining soluble cations (e.g., K, Na, Rb, Sr) and accessory minerals containing HFSE (e.g., Zr, Hf, U, Th) and REE. In contrast, silicate dust chemistry in desert basins (e.g., Bodélé Depression) is influenced by a longer history of transport, physical winnowing (e.g., loss of Zr, Hf, Th), chemical leaching (e.g., loss of Na, K, Rb), and mixing with intrabasinal materials such as diatoms and evaporitic salts. Mineral aerosols blown along the corridor by the winter Harmattan winds mix these basinal and basement materials. Dusts blown into the corridor from sub-Saharan Africa during the summer monsoon source from deeply chemically weathered terrains and are therefore likely to be more kaolinitic and stripped of mobile elements (e.g., Na, K, Mg, Ca, LILE), but retain immobile and resistant elements (e.g., Zr, Hf, REE). Finally, dusts blown southwestwards into the corridor from along the Atlantic Coastal Basin will be enriched in carbonate from Mesozoic-Cenozoic marine limestones, depleted in Th, Nb, and Ta, and locally contaminated by uranium-bearing phosphate deposits.

Climate change and plant dispersal along corridors in fragmented landscapes of Mesoamerica

PubMed Central

Imbach, Pablo A; Locatelli, Bruno; Molina, Luis G; Ciais, Philippe; Leadley, Paul W

2013-01-01

Climate change is a threat to biodiversity, and adaptation measures should be considered in biodiversity conservation planning. Protected areas (PA) are expected to be impacted by climate change and improving their connectivity with biological corridors (BC) has been proposed as a potential adaptation measure, although assessing its effectiveness remains a challenge. In Mesoamerica, efforts to preserve the biodiversity have led to the creation of a regional network of PA and, more recently, BC. This study evaluates the role of BC for facilitating plant dispersal between PA under climate change in Mesoamerica. A spatially explicit dynamic model (cellular automaton) was developed to simulate species dispersal under different climate and conservation policy scenarios. Plant functional types (PFT) were defined based on a range of dispersal rates and vegetation types to represent the diversity of species in the region. The impacts of climate change on PA and the role of BC for dispersal were assessed spatially. Results show that most impacted PA are those with low altitudinal range in hot, dry, or high latitude areas. PA with low altitudinal range in high cool areas benefit the most from corridors. The most important corridors cover larger areas and have high altitude gradients. Only the fastest PFT can keep up with the expected change in climate and benefit from corridors for dispersal. We conclude that the spatial assessment of the vulnerability of PA and the role of corridors in facilitating dispersal can help conservation planning under a changing climate. PMID:24101983

Integrated corridor management analysis, modeling, and simulation for the I–15 corridor in San Diego, California—post-deployment analysis plan.

DOT National Transportation Integrated Search

2016-11-01

Post-Deployment Analysis, Modeling, and Simulation (AMS) activities focus on identifying impacts and benefits of the as-deployed Integrated Corridor Management (ICM) system. The as-deployed ICM strategies may differ from as-planned ...

Integrated corridor management : analysis, modeling, and simulation for the U.S.-15 corridor in Dallas, Texas—post-deployment analysis plan.

DOT National Transportation Integrated Search

2016-10-01

Post-Deployment Analysis, Modeling, and Simulation (AMS) activities focus on identifying impacts and benefits of the as-deployed Integrated Corridor Management (ICM) system. The as-deployed ICM strategies may differ from as-planned ...

Can warmwater streams be rehabilitated using watershed-scale standard erosion control measures alone?

PubMed

Shields, F Douglas; Knight, Scott S; Cooper, Charles M

2007-07-01

Degradation of warmwater streams in agricultural landscapes is a pervasive problem, and reports of restoration effectiveness based on monitoring data are rare. Described is the outcome of rehabilitation of two deeply incised, unstable sand-and-gravel-bed streams. Channel networks of both watersheds were treated using standard erosion control measures, and aquatic habitats within 1-km-long reaches of each stream were further treated by addition of instream structures and planting woody vegetation on banks ("habitat rehabilitation"). Fish and their habitats were sampled semiannually during 1-2 years before rehabilitation, 3-4 years after rehabilitation, and 10-11 years after rehabilitation. Reaches with only erosion control measures located upstream from the habitat measure reaches and in similar streams in adjacent watersheds were sampled concurrently. Sediment concentrations declined steeply throughout both watersheds, with means > or = 40% lower during the post-rehabilitation period than before. Physical effects of habitat rehabilitation were persistent through time, with pool habitat availability much higher in rehabilitated reaches than elsewhere. Fish community structure responded with major shifts in relative species abundance: as pool habitats increased after rehabilitation, small-bodied generalists and opportunists declined as certain piscivores and larger-bodied species such as centrarchids and catostomids increased. Reaches without habitat rehabilitation were significantly shallower, and fish populations there were similar to the rehabilitated reaches prior to treatment. These findings are applicable to incised, warmwater streams draining agricultural watersheds similar to those we studied. Rehabilitation of warmwater stream ecosystems is possible with current knowledge, but a major shift in stream corridor management strategies will be needed to reverse ongoing degradation trends. Apparently, conventional channel erosion controls without instream habitat

Planning the Transition to Long-Term Stewardship for the River Corridor

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

Cearlock, C.S.; Lerch, J.A.; Sands, J.P.

2007-07-01

Long-term stewardship refers to all activities necessary to ensure protection of human health and the environment following completion of remediation, disposal, or stabilization of a site or a portion of a site. Efforts to establish the proposed approach and criteria to be met for long-term stewardship in the river corridor of the Hanford Site in Richland, Washington, are currently being established and a draft plan is expected to be completed in mid-2007 to facilitate planning for a smooth and seamless transition to long-term stewardship. Once the initial criteria have been established, supporting information will be gathered as the work proceeds.more » Near the end of cleanup actions under the River Corridor Closure Contract, these criteria will be finalized in a long-term stewardship plan that documents how the criteria have been met. In addition, the final long-term stewardship plan will also contain a proposed Finding of Suitability to Transfer in accordance with Comprehensive Environmental Response, Compensation, and Liability Act of 1980 Section 120(h) [1]. This final long-term stewardship plan will provide the foundation for post-River Corridor Closure Contract and management activities in the river corridor pending actual property transfer from the U.S. Department of Energy. (authors)« less

Swift fox survey along Heartland Expressway Corridor.

DOT National Transportation Integrated Search

2015-05-01

The swift fox (Vulpes velox) is a small canid classified as endangered within the : state of Nebraska. Future construction of the Heartland Expressway Corridor (HEC), a : 300 km road expansion project in the panhandle of the state, may impact the res...

Highway corridor preservation : a synthesis of practice.

DOT National Transportation Integrated Search

1989-01-01

This report examines the general concept of planning for and protecting land designated to serve as new highway corridors in developing areas. It generally presents a review of the state of the practice by describing several methods for protecting po...

Stream sediment sources in midwest agricultural basins with land retirement along channel

USGS Publications Warehouse

Williamson, Tanja N.; Christensen, Victoria G.; Richardson, William B.; Frey, Jeffrey W.; Gellis, Allen C.; Kieta, K. A.; Fitzpatrick, Faith A.

2014-01-01

Documenting the effects of agricultural land retirement on stream-sediment sources is critical to identifying management practices that improve water quality and aquatic habitat. Particularly difficult to quantify are the effects from conservation easements that commonly are discontinuous along channelized streams and ditches throughout the agricultural midwestern United States. Our hypotheses were that sediment from cropland, retired land, stream banks, and roads would be discernible using isotopic and elemental concentrations and that source contributions would vary with land retirement distribution along tributaries of West Fork Beaver Creek in Minnesota. Channel-bed and suspended sediment were sampled at nine locations and compared with local source samples by using linear discriminant analysis and a four-source mixing model that evaluated seven tracers: In, P, total C, Be, Tl, Th, and Ti. The proportion of sediment sources differed significantly between suspended and channel-bed sediment. Retired land contributed to channel-bed sediment but was not discernible as a source of suspended sediment, suggesting that retired-land material was not mobilized during high-flow conditions. Stream banks were a large contributor to suspended sediment; however, the percentage of stream-bank sediment in the channel bed was lower in basins with more continuous retired land along the riparian corridor. Cropland sediments had the highest P concentrations; basins with the highest cropland-sediment contributions also had the highest P concentrations. Along stream reaches with retired land, there was a lower proportion of cropland material in suspended sediment relative to sites that had almost no land retirement, indicating less movement of nutrients and sediment from cropland to the channel as a result of land retirement.

US-75 ICM system as-built design : Dallas Integrated Corridor Management (ICM) demonstration project.

DOT National Transportation Integrated Search

2015-05-01

This As-Built document for the US-75 Integrated Corridor Management (ICM) Program has been developed as part of the US Department of Transportation Integrated Corridor Management Initiative. The basic premise behind the ICM initiative is that indepen...

An experimental test of matrix permeability and corridor use by an endemic understory bird.

PubMed

Castellón, Traci D; Sieving, Kathryn E

2006-02-01

Because of widespread habitat fragmentation, maintenance of landscape connectivity has become a major focus of conservation planning, but empirical tests of animal movement in fragmented landscapes remain scarce. We conducted a translocation experiment to test the relative permeability of three landscape elements (open habitat, shrubby secondary vegetation, and wooded corridors) to movement by the Chucao Tapaculo (Scelorchilus rubecula), a forest understory bird endemic to South American temperate rainforest. Forty-one radio-tagged subjects were translocated (individually) to three landscape treatments consisting of small release patches that were either entirely surrounded by open habitat (pasture), entirely surrounded by dense shrubs, or linked to other patches by wooded corridors that were otherwise surrounded by open matrix. The number of days subjects remained in release patches before dispersal (a measure of habitat resistance) was significantly longer for patches surrounded by open habitat than for patches adjoining corridors or surrounded by dense shrubs. These results indicate that open habitat significantly constrains Chucao dispersal, in accord with expectation, but dispersal occurs equally well through wooded corridors and shrub-dominated matrix. Thus, corridor protection or restoration and management of vegetation in the matrix (to encourage animal movement) may be equally feasible alternatives for maintaining connectivity.

Oceanic Situational Awareness over the North Atlantic Corridor

NASA Technical Reports Server (NTRS)

Welch, Bryan; Greenfield, Israel

2005-01-01

Air traffic control (ATC) mandated, aircraft separations over the oceans impose a limitation on traffic capacity for a given corridor, given the projected traffic growth over the oceanic domain. The separations result from a lack of acceptable situational awareness over oceans where radar position updates are not available. This study considers the use of Automatic Dependent Surveillance (ADS) data transmitted over a commercial satellite communications system as an approach to provide ATC with the needed situational awareness and thusly allow for reduced aircraft separations. This study uses Federal Aviation Administration data from a single day for the North Atlantic Corridor to analyze traffic loading to be used as a benchmark against which to compare several approaches for coordinating data transmissions from the aircraft to the satellites.

76 FR 31008 - North Central Iowa Rail Corridor, LLC-Acquisition Exemption-Union Pacific Railroad Company

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-27

... Rail Corridor, LLC--Acquisition Exemption-- Union Pacific Railroad Company North Central Iowa Rail Corridor, LLC (NCIRC), a noncarrier, has filed a verified notice of exemption under 49 [[Page 31009

Reducing The Risk Of Abrupt Climate Change: Emission Corridors Preserving The Thermohaline Circulation

NASA Astrophysics Data System (ADS)

Zickfeld, K.

Paleo-reconstructions have shown that large and abrupt climate changes have occurred throughout the last ice-age cycles. This evidence, supplemented by insights into the complex and nonlinear nature of the climate system, gives raise to the concern that anthropogenic forcing may trigger such events in the future. A prominent example for such a potential climatic shift is the collapse of the North Atlantic thermohaline circu- lation (THC), which would cause a major cooling of the northern North Atlantic and north-western Europe and considerable regional sea level rise, with possibly severe consequences on, e.g., fisheries, agriculture and ecosystems. In this paper we present emission corridors for the 21st century preserving the THC. Emission corridors embrace the range of future emissions beyond which either the THC collapses or the mitigation burden becomes intolerable. They are calculated along the conceptual and methodological lines of the tolerable windows approach. We investigate the sensitivity of the emission corridors to the main uncertain parame- ters (climate and North Atlantic hydrological sensitivities as well as emissions of non CO_2 greenhouse gases). Results show a high dependence of the size of the emis- sion corridors on hydrological and climate sensitivities. For the best-guess values of both parameters we find that the emission corridors are wider than the range spanned by the SRES emissions scenarios. Thus, no immediate mitigation seems necessary in order to preserve the THC. For high but still realistic values of the sensitivities, however, even the low SRES emissions scenarios transgress the corridor boundaries. These findings imply that under 'business as usual' a non-negligible risk of either a THC collapse or an intolerable mitigation burden exists.

Risk Assessment Approach for the Hanford Site River Corridor Closure Project

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

Thomson, J.E.; Weiss, S.G.; Sands, J.P.

2007-07-01

The river corridor portion of the U.S. Department of Energy's (DOE) Hanford Site includes the 100 Area and 300 Area, which border the Columbia River and cover 565 km{sup 2} (218 mi{sup 2}). The River Corridor Closure (RCC) Project scope of work includes 486 contaminated facilities, 4 of 9 deactivated plutonium production reactors, and 370 waste disposal sites. DOE's cleanup actions in the river corridor were initiated in 1994 under the Comprehensive Environmental Response, Compensation, and Liability Act of 1981 (42 U.S.C. 9601, et seq.) (CERCLA) and included source and groundwater operable units (OUs). DOE's RCC Project, awarded to Washingtonmore » Closure Hanford (WCH) in 2005, focuses on source OUs and has allowed cleanup actions to continue in the 100 and 300 Areas with completion by 2013. The regulatory authorization for cleanup actions at source OUs in the river corridor consists primarily of interim action records of decision (RODs), which were supported by qualitative risk assessments and limited field investigations. A key to establishing final cleanup decisions and proceeding toward final CERCLA closeout is completion of quantitative baseline risk assessment activities. Baseline risk assessment is necessary to determine whether cleanup actions are protective of human health and the environment and to identify any course corrections needed to ensure that current and future cleanup actions are protective. Because cleanup actions are ongoing under interim action RODs, it is desirable to establish the final cleanup decision bases as early as possible to minimize the impacts of any identified course corrections to the cleanup approach. Risk assessment is being performed by WCH as the River Corridor Baseline Risk Assessment (RCBRA). The RCBRA uses a multi-step process that summarizes existing data; uses the data quality objectives process to identify both data gaps and unresolved issues through public workshops; and solicits input from regulators, trustees

Indirect Validation of Probe Speed Data on Arterial Corridors

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

Eshragh, Sepideh; Young, Stanley E.; Sharifi, Elham

This study aimed to estimate the accuracy of probe speed data on arterial corridors on the basis of roadway geometric attributes and functional classification. It was assumed that functional class (medium and low) along with other road characteristics (such as weighted average of the annual average daily traffic, average signal density, average access point density, and average speed) were available as correlation factors to estimate the accuracy of probe traffic data. This study tested these factors as predictors of the fidelity of probe traffic data by using the results of an extensive validation exercise. This study showed strong correlations betweenmore » these geometric attributes and the accuracy of probe data when they were assessed by using average absolute speed error. Linear models were regressed to existing data to estimate appropriate models for medium- and low-type arterial corridors. The proposed models for medium- and low-type arterials were validated further on the basis of the results of a slowdown analysis. These models can be used to predict the accuracy of probe data indirectly in medium and low types of arterial corridors.« less

Effect of course length and corridor width on the 2-minute walk test performance in geriatric patients.

PubMed

Lindemann, Ulrich; Beck, Luisa; Becker, Clemens

2017-02-01

To evaluate the effect of course length and corridor width on 2-minute walk test results in older adults. Cross-sectional and experimental study with different test conditions. Geriatric rehabilitation clinic. A total of 21 patients (median age 81 years). Patients walked two minutes on a 20 m and 40 m course with a 2 m or 1 m corridor width and on a continuous course without any turning in a corridor of 2 m width, five walks in total. The distance traveled within the 2 minutes was recorded. Compared with the 20 m course length, median walking distances measured by the 2-minute walk test in a walk way 2 m broad were better on the continuous corridor without any turn (136.9 m vs. 129.3 m, p = 0.002) and on the 40 m course (131.8 m vs. 129.3 m, p = 0.003). Walking distance on a 20 m course length was longer in a corridor of 2 m width compared with the 1 m corridor width (129.3 m vs. 119.2 m, p = 0.005). The walking distance was not affected by corridor width on the 40 m course length. Performance of elderly patients on the 2-minute walk test is influenced by the width of the corridor and the length of the course used.

78 FR 73559 - Moose-Wilson Corridor Comprehensive Management Plan, Environmental Impact Statement, Grand Teton...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-06

...-Wilson Corridor Comprehensive Management Plan, Environmental Impact Statement, Grand Teton National Park... is preparing a Comprehensive Management Plan and Environmental Impact Statement (EIS) for the Moose...; (2) distinguish the corridor's fundamental and other important resources and values; (3) clearly...

New York in the new world economy : the I-90 corridor study : final report

DOT National Transportation Integrated Search

2002-12-01

The I-90 Corridor in upstate New York is a classic example of the de-industrialization of the Northeastern United States. With few exceptions, all counties along the corridor have experienced marked declined in manufacturing employment over the past ...

Blood Parasites of Blue-winged Teal ( Anas discors ) from Two Migratory Corridors, in the Southern USA.

PubMed

Garvon, Jason M; Mott, Joanna B; Jacobs, Sandy Serio; Fedynich, Alan M

2016-07-01

We collected 180 Blue-winged Teal ( Anas discors ) in September and October 2002 from Florida, US (n=100, representing the eastern migratory corridor) and the Louisiana-Texas, US, border (n=80, representing the western migratory corridor) and examined for blood parasites using thin heart-blood smears. Leucocytozoon simondi, Haemoproteus nettionis, and microfilariae were found in 16, 23, and 27 birds, respectively. Prevalence of L. simondi and H. nettionis did not vary by migratory corridor, but the prevalence of microfilariae was higher in the western corridor (23%) than the eastern corridor (9%). No differences in prevalence of L. simondi, H. nettionis, and microfilariae were observed by host age or sex. The mean density of L. simondi and H. nettionis averaged 1.5±0.3 and 2.3±0.4 (±SE per 3,000 erythrocytes), respectively. Ranked abundance models for main and interactive effects of corridor, age, and sex were not statistically significant for L. simondi or H. nettionis. Low prevalence and abundance of hematozoa in early autumn migrants reflects the likelihood of low exposure probabilities of Blue-winged Teal on the breeding grounds, compared to their congeners.

Role of buccal corridor in smile esthetics and its correlation with underlying skeletal and dental structures.

PubMed

Tikku, Tripti; Khanna, Rohit; Maurya, R P; Ahmad, Nabeel

2012-01-01

This study was designed to evaluate the buccal corridor in smile esthetics and to correlate it with underlying hard tissues. Posed smiling frontal photographs, digital posterior-anterior (PA) cephalograms, and study models of 25 males and 25 females in age range of 18-25 years were taken. Photographs were evaluated for smile esthetics by eight orthodontists, eight plastic surgeons, eight beauticians and eight lay people to group them into three groups with least attractive, average and attractive smile and buccal corridor width was measured. Digital PA cephalograms were transferred on Nemo-tech software for frontal facial analysis. Intercanine and intermolar widths were measured on upper study model with the help of a digital calliper. The buccal corridor width was least in attractive smile group and maximum in least attractive smile group. The buccal corridor width had a negligible correlation with hard tissues and a mild to moderate inverse correlation with intercanine and intermolar widths within the groups. As the amount of buccal corridor display was increased, smiling images were scored less attractive by the evaluators. The buccal corridor is not influenced by underlying skeletal hard tissues but have mild to moderate inverse correlation with the intercanine and intermolar width.

Fluor Hanford (FH) River Corridor Transition Plan

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

MCBRIDE, D.J.

2002-08-28

This Transition Plan defines the scope and schedule for actions that are critical for a smooth transition of the River Corridor scope of work and to ensure the achievement of transition as planned, with minimal or no impact to ongoing baseline activities.

Sex-specific differences of the infraacetabular corridor: a biomorphometric CT-based analysis on a database of 523 pelves.

PubMed

Gras, Florian; Gottschling, Heiko; Schröder, Manuel; Marintschev, Ivan; Reimers, Nils; Burgkart, Rainer

2015-01-01

An infraacetabular screw path facilitates the closure of a periacetabular fixation frame to increase the plate fixation strength in acetabular fractures up to 50%. Knowledge of the variance in corridor sizes and axes has substantial surgical relevance for safe screw placement. (1) What proportion of healthy pelvis specimens have an infraacetabular corridor that is 5 mm or larger in diameter? (2) Does a universal corridor axis and specific screw entry point exist? (3) Are there sex-specific differences in the infraacetabular corridor size or axis and are these correlated with anthropometric parameters like age, body weight and height, or the acetabular diameter? A template pelvis with a mean shape from 523 segmented pelvis specimens was generated using a CT-based advanced image analyzing system. Each individual pelvis was registered to the template using a free-form registration algorithm. Feasible surface regions for the entry and exit points of the infraacetabular corridor were marked on the template and automatically mapped to the individual samples to perform a measurement of the maximum sizes and axes of the infraacetabular corridor on each specimen. A minimum corridor diameter of at least 5 mm was defined as a cutoff for placing a 3.5-mm cortical screw in clinical settings. In 484 of 523 pelves (93%), an infraacetabular corridor with a diameter of at least 5 mm was found. Using the mean axis angulations (54.8° [95% confidence interval {CI}, 0.6] from anterocranial to posterocaudal in relation to the anterior pelvic plane and 1.5° [95% CI, 0.4] from anteromedial to posterolateral in relation to the sagittal midline plane), a sufficient osseous corridor was present in 64% of pelves. Allowing adjustment of the three-dimensional axis by another 5° included an additional 25% of pelves. All corridor parameters were different between females and males (corridor diameter, 6.9 [95% CI, 0.2] versus 7.7 [95% CI, 0.2] mm; p<0.001; corridor length, 96.2 [95% CI, 0

76 FR 5203 - Draft Environmental Impact Statement, Stehekin River Corridor Implementation Plan, North Cascades...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-28

... Statement, Stehekin River Corridor Implementation Plan, North Cascades National Park Service Complex; Chelan... public comment period. SUMMARY: The National Park Service, in cooperation with the Federal Highway Administration, has prepared a combined Stehekin River Corridor Implementation Plan, Lake Chelan National...

Fire modeling in a nonventilated corridor

NASA Astrophysics Data System (ADS)

Lulea, Marius Dorin; Iordache, Vlad; Năstase, Ilinca

2018-02-01

The main objective of this study was to determine the effect of fire in a nonventilated corridor. A real-scale model of a corridor has been modeled in Fire Dynamics Simulator(F.D.S.) in order to determine the evolution of indoor temperatures, the visibility and the oxygen quantities during a fire. The start time of a sprinkler has also been determined. The use of sprinklers in buildings has become a necessity and a requirement imposed by technical norms. The provision of this type of installation has become a common feature in buildings with a high fire risk, with two main effects: fire extinction and protection of structural and partition elements from high temperatures[15]. The ultimate goal is to ensure optimal conditions for saving the building users, intervention teams and maintaining the stability of the building. Low temperatures and good visibility on the escape routes during a fire are the basic conditions to ensure the optimal evacuation of users.

Establishing Final Cleanup Decisions for the Hanford Site River Corridor

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

Lerch, J.A.; Sands, J.P.

2007-07-01

A major challenge in the River Corridor Closure Contract is establishing final cleanup decisions for the source operable units in the Hanford Site river corridor. Cleanup actions in the river corridor began in 1994 and have been performed in accordance with a 'bias for action' approach adopted by the Tri-Parties - the U.S. Department of Energy, U.S. Environmental Protection Agency, and Washington State Department of Ecology. This approach enabled early application of cleanup dollars on actual remediation of contaminated waste sites. Consequently, the regulatory framework authorizing cleanup actions at source operable units in the river corridor consists largely of interimmore » action records of decision, which were supported by qualitative risk assessments. Obtaining final cleanup decisions for the source operable units is necessary to determine whether past cleanup actions in the river corridor are protective of human health and the environment and to identify any course corrections that may be needed to ensure that ongoing and future cleanup actions are protective. Because the cleanup actions are ongoing, it is desirable to establish the final cleanup decisions as early as possible to minimize the impacts of any identified course corrections to the present cleanup approach. Development of a strategy to obtain final cleanup decisions for the source operable units in a manner that is responsive to desires for an integrated approach with the groundwater and Columbia River components while maintaining the ability to evaluate each component on its own merit represents a significant challenge. There are many different options for grouping final cleanup decisions, and each involved party or stakeholder brings slightly different interests that shape the approach. Regardless of the selected approach, there are several specific challenges and issues to be addressed before making final cleanup decisions. A multi-agency and contractor working group has been established to

Implementation of a subcanopy solar radiation model on a forested headwater basin in the Southern Appalachians to estimate riparian canopy density and stream insolation for stream temperature models

NASA Astrophysics Data System (ADS)

Belica, L.; Petras, V.; Iiames, J. S., Jr.; Caldwell, P.; Mitasova, H.; Nelson, S. A. C.

2016-12-01

Water temperature is a key aspect of water quality and understanding how the thermal regimes of forested headwater streams may change in response to climatic and land cover changes is increasingly important to scientists and resource managers. In recent years, the forested mountain watersheds of the Southeastern U.S. have experienced changing climatic patterns as well as the loss of a keystone riparian tree species and anticipated hydrologic responses include lower summer stream flows and decreased stream shading. Solar radiation is the main source of thermal energy to streams and a key parameter in heat-budget models of stream temperature; a decrease in flow volume combined with a reduction in stream shading during summer have the potential to increase stream temperatures. The high spatial variability of forest canopies and the high spatio-temporal variability in sky conditions make estimating the solar radiation reaching small forested headwater streams difficult. The Subcanopy Solar Radiation Model (SSR) (Bode et al. 2014) is a GIS model that generates high resolution, spatially explicit estimates of solar radiation by incorporating topographic and vegetative shading with a light penetration index derived from leaf-on airborne LIDAR data. To evaluate the potential of the SSR model to provide estimates of stream insolation to parameterize heat-budget models, it was applied to the Coweeta Basin in the Southern Appalachians using airborne LIDAR (NCALM 2009, 1m resolution). The LIDAR derived canopy characteristics were compared to current hyperspectral images of the canopy for changes and the SSR estimates of solar radiation were compared with pyranometer measurements of solar radiation at several subcanopy sites during the summer of 2016. Preliminary results indicate the SSR model was effective in identifying variations in canopy density and light penetration, especially in areas associated with road and stream corridors and tree mortality. Current LIDAR data and

Thick-skinned tectonics closing the Rifian Corridor

NASA Astrophysics Data System (ADS)

Capella, Walter; Matenco, Liviu; Dmitrieva, Evelina; Roest, Wilmer M. J.; Hessels, Suzanne; Hssain, Mohamed; Chakor-Alami, Abdelwahid; Sierro, Francisco J.; Krijgsman, Wout

2017-07-01

Tectonic processes in the Gibraltar region are associated with Africa-Iberia convergence and the formation of the Betic-Rif orogenic system. The Late Miocene shortening recorded in the Rif orogen resulted in gradual shallowing and eventual closure of the Rifian Corridor, a narrow marine gateway connecting the Atlantic Ocean with the Mediterranean Sea. This closure is associated with paleoenvironmental changes that ultimately led to the Mediterranean Messinian Salinity Crisis. Here we present a structural analysis based on a combination of field kinematic data and interpretation of reflection seismic lines acquired for petroleum exploration to understand the deformational phases associated with the closure of the Rifian Corridor. We show the succession of three Late Miocene to present day events, an initial thin-skinned nappe thrusting, followed by regional subsidence and continued by thick-skinned contraction. The transition from in sequence thin-skinned tectonics during subduction to thick-skinned contraction during continental collision resulted in significant acceleration of tectonic uplift and associated exhumation. This is related to a change in the regional deformation linked to plate convergence, but possibly also coupled with deep lithospheric or dynamic topography processes. Such a mechanism is also common for other Mediterranean orogens during late stages of slab retreat, where accelerated tectonics resulted in rapid sedimentation and associated basins evolution. We conclude that the thick-skinned contraction in the Rif orogeny initiated in the late Tortonian, has created a cumulative uplift in the order of 1 km, and provided high enough uplift rates to close the Rifian Corridor.

DOWN-STREAM SPATIAL DISTRIBUTION OF ANTIBIOTIC RESISTANCE TRAITS ALONG METAL CONTAMINATED STREAM REACHES

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

Tuckfield, C; J V Mcarthur

2007-04-16

Sediment bacteria samples were collected from three streams in South Carolina, two contaminated with multiple metals (Four Mile Creek and Castor Creek), one uncontaminated (Meyers Branch), and another metal contaminated stream (Lampert Creek) in northern Washington State. Growth plates inoculated with Four Mile Creek sample extracts show bacteria colony growth after incubation on plates containing either one of two aminoglycosides (kanamycin or streptomycin), tetracycline or chloramphenocol. This study analyzes the spatial pattern of antibiotic resistance in culturable sediment bacteria in all four streams that may be due to metal contamination. We summarize the two aminoglycoside resistance measures and the 10more » metals concentrations by Principal Components Analysis. Respectively, 63% and 58% of the variability was explained in the 1st principal component of each variable set. We used the respective multivariate summary metrics (i.e. 1st principal component scores) as input measures for exploring the spatial correlation between antibiotic resistance and metal concentration for each stream reach sampled. Results show a significant and negative correlation between metals scores versus aminoglycoside resistance scores and suggest that selection for metal tolerance among sediment bacteria may influence selection for antibiotic resistance differently than previously supposed.. In addition, we borrow a method from geostatistics (variography) wherein a spatial cross-correlation analysis shows that decreasing metal concentrations scores are associated with increasing aminoglycoside resistance scores as the separation distance between sediment samples decreases, but for contaminated streams only. Since these results were counter to our initial expectation and to other experimental evidence for water column bacteria, we suspect our field results are influenced by metal bioavailability in the sediments and by a contaminant promoted interaction or ''cocktail effect

Atmospherically-driven collapse of a marine-based ice stream

NASA Astrophysics Data System (ADS)

Greenwood, S. L.; Clason, C. C.

2016-12-01

Marine-terminating glaciers and the sectors of ice sheets that are grounded below sea level are widely considered to be vulnerable to unstable retreat. The southern sector of the retreating Fennoscandian Ice Sheet comprised a large, aqueous-terminating ice sheet catchment grounded well below sea level throughout its deglaciation. However, the behaviour, timing of and controls upon ice sheet retreat through the Baltic and Bothnian basins have thus far been inferred only indirectly from peripheral, terrestrial-based geological archives. Recent acquisition of high-resolution multibeam bathymetry opens these basins up, for the first time, to direct investigation of their glacial footprint and palaeo-ice sheet behaviour. Multibeam data reveal a rich glacial landform legacy of the Bothnian Sea deglaciation. A late-stage palaeo-ice stream formed a narrow corridor of fast flow. Its pathway is overprinted by a vast field of basal crevasse squeeze ridges, while abundant traces of high subglacial meltwater volumes call for considerable input of surface meltwater to the subglacial system. We interpret a short-lived ice stream event under high extension, precipitating large-scale hydrofracture-driven collapse of the ice sheet sector under conditions of high surface melting. Experiments with a physically-based numerical flowline model indicate that the rate and pattern of Bothnian Sea ice stream retreat are most sensitive to surface mass balance change and crevasse propagation, while remarkably insensitive to submarine melting and sea level change. We interpret strongly atmospherically-driven retreat of this marine-based ice sheet sector.

Secure corridor for infraacetabular screws in acetabular fracture fixation-a 3-D radiomorphometric analysis of 124 pelvic CT datasets.

PubMed

Arlt, Stephan; Noser, Hansrudi; Wienke, Andreas; Radetzki, Florian; Hofmann, Gunther Olaf; Mendel, Thomas

2018-05-21

Acetabular fracture surgery is directed toward anatomical reduction and stable fixation to allow for the early functional rehabilitation of an injured hip joint. Recent biomechanical investigations have shown the superiority of using an additional screw in the infraacetabular (IA) region, thereby transfixing the separated columns to strengthen the construct by closing the periacetabular fixation frame. However, the inter-individual existence and variance concerning secure IA screw corridors are poorly understood. This computer-aided 3-D radiomorphometric study examined 124 CT Digital Imaging and Communications in Medicine (DICOM) datasets of intact human pelves (248 acetabula) to visualize the spatial IA corridors as the sum of all intraosseous screw positions. DICOM files were pre-processed using the Amira® 4.2 visualization software. Final corridor computation was accomplished using a custom-made software algorithm. The volumetric measurement data of each corridor were calculated for further statistical analyses. Correlations between the volumetric values and the biometric data were investigated. Furthermore, the influence of hip dysplasia on the IA corridor configuration was analyzed. The IA corridors consistently showed a double-cone shape with the isthmus located at the acetabular fovea. In 97% of male and 91% of female acetabula, a corridor for a 3.5-mm screw could be found. The number of IA corridors was significantly lower in females for screw diameters ≥ 4.5 mm. The mean 3.5-mm screw corridor volume was 16 cm 3 in males and 9.2 cm 3 in female pelves. Corridor volumes were significantly positively correlated with body height and weight and with the diameter of Köhler's teardrop on standard AP pelvic X-rays. No correlation was observed between hip dysplasia and the IA corridor extent. IA corridors are consistently smaller in females. However, 3.5-mm small fragment screws may still be used as the standard implant because sex-specific differences are

Postglacial viability and colonization in North America's ice-free corridor.

PubMed

Pedersen, Mikkel W; Ruter, Anthony; Schweger, Charles; Friebe, Harvey; Staff, Richard A; Kjeldsen, Kristian K; Mendoza, Marie L Z; Beaudoin, Alwynne B; Zutter, Cynthia; Larsen, Nicolaj K; Potter, Ben A; Nielsen, Rasmus; Rainville, Rebecca A; Orlando, Ludovic; Meltzer, David J; Kjær, Kurt H; Willerslev, Eske

2016-09-01

During the Last Glacial Maximum, continental ice sheets isolated Beringia (northeast Siberia and northwest North America) from unglaciated North America. By around 15 to 14 thousand calibrated radiocarbon years before present (cal. kyr bp), glacial retreat opened an approximately 1,500-km-long corridor between the ice sheets. It remains unclear when plants and animals colonized this corridor and it became biologically viable for human migration. We obtained radiocarbon dates, pollen, macrofossils and metagenomic DNA from lake sediment cores in a bottleneck portion of the corridor. We find evidence of steppe vegetation, bison and mammoth by approximately 12.6 cal. kyr bp, followed by open forest, with evidence of moose and elk at about 11.5 cal. kyr bp, and boreal forest approximately 10 cal. kyr bp. Our findings reveal that the first Americans, whether Clovis or earlier groups in unglaciated North America before 12.6 cal. kyr bp, are unlikely to have travelled by this route into the Americas. However, later groups may have used this north-south passageway.

Helminth Community Dynamics in Populations of Blue-Winged Teal (Anas discors) Using Two Distinct Migratory Corridors.

PubMed

Garvon, Jason M; Fedynich, Alan M; Peterson, Markus J; Pence, Danny B

2011-01-01

The influence of spatially distinct host subpopulations on helminth community structure and pattern was examined in a migratory avian host species. Forty helminth species represented by 24,082 individuals were collected from 184 blue-winged teal (Anas discors; BWT) from 2 primary migratory corridors in Florida (eastern migratory corridor; EMC) and Louisiana and Texas (western migratory corridor; WMC). Mean species richness was greater in BWT from the WMC (x̅±SE = 10.2 ± 0.3 species) than the EMC (8.6 ± 0.2). The helminth community from the WMC had higher abundances of 6 common/intermediate species. Corridor helminth communities were similar in species composition but less similar when incorporating abundances of those species. Overlapping distributions of phylogenetically related host species that share generalist helminth species across ecologically similar habitats seem to mitigate the isolating mechanisms that are necessary for the distinct coevolutionary pathways to develop between adjacent corridors.

Urban Power Line Corridors as Novel Habitats for Grassland and Alien Plant Species in South-Western Finland

PubMed Central

Lampinen, Jussi; Ruokolainen, Kalle; Huhta, Ari-Pekka

2015-01-01

Regularly managed electric power line corridors may provide habitats for both early-successional grassland plant species and disturbance-dependent alien plant species. These habitats are especially important in urban areas, where they can help conserve native grassland species and communities in urban greenspace. However, they can also provide further footholds for potentially invasive alien species that already characterize urban areas. In order to implement power line corridors into urban conservation, it is important to understand which environmental conditions in the corridors favor grassland species and which alien species. Likewise it is important to know whether similar environmental factors in the corridors control the species composition of the two groups. We conducted a vegetation study in a 43 kilometer long urban power line corridor network in south-western Finland, and used generalized linear models and distance-based redundancy analysis to determine which environmental factors best predict the occurrence and composition of grassland and alien plant species in the corridors. The results imply that old corridors on dry soils and steep slopes characterized by a history as open areas and pastures are especially suitable for grassland species. Corridors suitable for alien species, in turn, are characterized by productive soils and abundant light and are surrounded by a dense urban fabric. Factors controlling species composition in the two groups are somewhat correlated, with the most important factors including light abundance, soil moisture, soil calcium concentration and soil productivity. The results have implications for grassland conservation and invasive alien species control in urban areas. PMID:26565700

Urban Power Line Corridors as Novel Habitats for Grassland and Alien Plant Species in South-Western Finland.

PubMed

Lampinen, Jussi; Ruokolainen, Kalle; Huhta, Ari-Pekka

2015-01-01

Regularly managed electric power line corridors may provide habitats for both early-successional grassland plant species and disturbance-dependent alien plant species. These habitats are especially important in urban areas, where they can help conserve native grassland species and communities in urban greenspace. However, they can also provide further footholds for potentially invasive alien species that already characterize urban areas. In order to implement power line corridors into urban conservation, it is important to understand which environmental conditions in the corridors favor grassland species and which alien species. Likewise it is important to know whether similar environmental factors in the corridors control the species composition of the two groups. We conducted a vegetation study in a 43 kilometer long urban power line corridor network in south-western Finland, and used generalized linear models and distance-based redundancy analysis to determine which environmental factors best predict the occurrence and composition of grassland and alien plant species in the corridors. The results imply that old corridors on dry soils and steep slopes characterized by a history as open areas and pastures are especially suitable for grassland species. Corridors suitable for alien species, in turn, are characterized by productive soils and abundant light and are surrounded by a dense urban fabric. Factors controlling species composition in the two groups are somewhat correlated, with the most important factors including light abundance, soil moisture, soil calcium concentration and soil productivity. The results have implications for grassland conservation and invasive alien species control in urban areas.

Effects of stream acidification and habitat on fish populations of a North American river

USGS Publications Warehouse

Baldigo, Barry P.; Lawrence, G.B.

2001-01-01

Water quality, physical habitat, and fisheries at sixteen reaches in the Neversink River Basin were studied during 1991-95 to identify the effects of acidic precipitation on stream-water chemistry and on selected fish-species populations, and to test the hypothesis that the degree of stream acidification affected the spatial distribution of each fish-species population. Most sites on the East Branch Neversink were strongly to severely acidified, whereas most sites on the West Branch were minimally to moderately acidified. Mean density of fish populations ranged from 0 to 2.15 fish/m2; biomass ranged from 0 to 17.5 g/m2. Where brook trout were present, their population density ranged from 0.04 to 1.09 fish/m2, biomass ranged from 0.76 to 12.2 g/m2, and condition (K) ranged from 0.94 to 1.07. Regression analyses revealed strong relations (r2 ?? 0.41 to 0.99; p ??? 0.05) between characteristics of the two most common species (brook trout and slimy sculpin) populations and mean concentrations of inorganic monomeric aluminum (Alim), pH, Si, K+, NO3/-, NH4/+, DOC, Ca2+, and Na+; acid neutralizing capacity (ANC); and water temperature. Stream acidification may have adversely affected fish populations at most East Branch sites, but in other parts of the Neversink River Basin these effects were masked or mitigated by other physical habitat, geochemical, and biological factors.

Relationship of the lumbar plexus branches to the lumbar spine: anatomical study with application to lateral approaches.

PubMed

Tubbs, Richard Isaiah; Gabel, Brandon; Jeyamohan, Shiveindra; Moisi, Marc; Chapman, Jens R; Hanscom, R David; Loukas, Marios; Oskouian, Rod J; Tubbs, Richard Shane

2017-07-01

Injuries to the lumbar plexus during lateral approaches to the spine are not uncommon and may result in permanent deficits. However, the literature contains few studies that provide landmarks for avoiding the branches of the lumbar plexus. The present anatomical study was performed to elucidate the course of these nerves in relation to lateral approaches to the lumbar spine. This is a quantitative anatomical cadaveric study. The lumbar plexus and its branches were dissected on 12 cadaveric sides. Metal wires were laid on the nerves along their paths on the posterior abdominal wall. Fluoroscopy was performed in the anteroposterior and lateral positions. The relationships between regional bony landmarks and the branches of the lumbar plexus were observed. When viewed laterally, the greatest concentration of nerves occurred from the posteroinferior aspect of L4, inferior along the posterior one-third of the body of L5, then at the level of the sacral promontory. On the basis of our study, approaches to the anterior two-thirds of the L4 vertebra and anterior third of L5 will result in the lowest chance of lumbar plexus nerve injury. In addition, lateral muscle dissection through the psoas major should be in a superior to inferior direction in order to minimize nerve injury. Laterally, the widest corridor between branches in the abdominal wall was between the subcostal and iliohypogastric nerves. The findings of our cadaveric study provide surgeons who approach the lateral lumbar spine with data that could decrease injuries to the branches of the lumbar plexus, thus lessening patient morbidity. Copyright © 2017 Elsevier Inc. All rights reserved.

Air transportation in the California Corridor of 2010

NASA Technical Reports Server (NTRS)

Cameron, M.; Mahaffy, K.; Yanagi, G.; Lechmanski, L.; Riddle, T.; Howard, K.; Chan, C.; Gorman, M.; Bauer, B.

1989-01-01

The topic of the 1988-1989 NASA/USRA Advanced Design Project at California Polytechnic State University, San Luis Obispo, was the development of an air transportation system to meet the needs of the California Corridor for the year 2010. As aircraft design is taught by two instructors having different philosophies about the teaching process, the two classes took different approaches to address the problem. The first part of this summary (California Air Transit System) represents the work done by the students of Professor A. E. Andreoli, who followed a systems approach, emphasizing the determination of the proper mission. The second part of the summary (Four Aircraft to Service the California Corridor) contains the four aircraft designed by Dr. D. R. Sandlin's class based on specifications determined from work done in previous years.

78 FR 52602 - Notice To Rescind a Notice of Intent and Draft Environmental Impact Statement: I-17 Corridor...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-23

... and Draft Environmental Impact Statement: I-17 Corridor Improvement Study; Maricopa County, Arizona... Corridor Improvement Study was published in the Federal Register on January 6, 2010. FOR FURTHER... Corridor is located in the city of Phoenix, and the study area limits for the EIS consisted of...

Transsacral Osseous Corridor Anatomy Is More Amenable To Screw Insertion In Males: A Biomorphometric Analysis of 280 Pelves.

PubMed

Gras, Florian; Gottschling, Heiko; Schröder, Manuel; Marintschev, Ivan; Hofmann, Gunther O; Burgkart, Rainer

2016-10-01

Percutaneous iliosacral screw placement is the standard procedure for fixation of posterior pelvic ring lesions, although a transsacral screw path is being used more frequently in recent years owing to increased fracture-fixation strength and better ability to fix central and bilateral sacral fractures. However, biomorphometric data for the osseous corridors are limited. Because placement of these screws in a safe and effective manner is crucial to using transsacral screws, we sought to address precise sacral anatomy in more detail to look for anatomic variation in the general population. We asked: (1) What proportion of healthy pelvis specimens have no transsacral corridor at the level of the S1 vertebra owing to sacral dysmorphism? (2) If there is no safe diameter for screw placement in the transsacral S1 corridor, is an increased and thus safe diameter of the transsacral S2 corridor expected? (3) Are there sex-specific differences in sacral anatomy and are these correlated with known anthropometric parameters? CT scans of pelves of 280 healthy patients acquired exclusively for medical indications such as polytrauma (20%), CT angiography (70%), and other reasons (10%), were segmented manually. Using an advanced CT-based image analysis system, the mean shape of all segmented pelves was generated and functioned as a template. On this template, the cylindric transsacral osseous corridor at the level of the S1 and S2 vertebrae was determined manually. Each pelvis then was registered to the template using a free-form registration algorithm to measure the maximum screw corridor diameters on each specimen semiautomatically. Thirty of 280 pelves (11%) had no transsacral S1 corridor owing to sacral dysmorphism. The average of maximum cylindrical diameters of the S1 corridor for the remaining 250 pelves was 12.8 mm (95% CI, 12.1-13.5 mm). A transverse corridor for S2 was found in 279 of 280 pelves, with an average of maximum cylindrical diameter of 11.6 mm (95% CI, 11

Integrated corridor management, concept development and foundational research. Task 5.5, identification of analysis needs.

DOT National Transportation Integrated Search

2006-08-28

Task 5 - Identify Corridor Types, Operational Approaches and Strategies, and Analysis Tools - is part of the overall foundational research to further the understanding of various aspects of Integrated Corridor Management (ICM) and to identify integra...

Moving beyond science to protect a mammalian migration corridor.

PubMed

Berger, Joel; Cain, Steven L

2014-10-01

As the discipline of conservation biology evolves and practitioners grow increasingly concerned about how to put results into achievable conservation, it is still unclear the extent to which science drives conservation outcomes, especially across rural landscapes. We addressed this issue by examining the role of science in the protection of a biological corridor. Our focus is on a North American endemic mammal reliant on long distance migration as an adaptive strategy, the pronghorn (Antilocapra americana) of the southern Greater Yellowstone Ecosystem. The role of science in realizing policy change, while critical as a first step, was surprisingly small relative to the role of other human dimensions. In a case study, we strategically addressed a variety of conservation needs beyond science, first by building a partnership between government and private interests and then by enhancing interest in migratory phenomena across a landscape with divergent political ideologies and economic bases. By developing awareness and even people's pride in the concept of corridor conservation, we achieved local, state, and federal acceptance for protection of a 70 km long, 2 km wide pathway for the longest terrestrial migrant in the contiguous United States. Key steps included conducting and publishing research that defined the migration corridor; fostering a variety of media coverage at local, regional, and national levels; conducting public outreach through stakeholder workshops, meetings, and presentations; and meeting with and gaining the support of elected officials. All these contributed to the eventual policy change that created the first federally protected migration corridor in the United States, which in turn stimulated additional conservation actions. On the basis of our experience, we believe conservation scientists can and should step beyond traditional research roles to assist with on-the-ground conservation by engaging in aspects of conservation that involve local

Modelling Fine Scale Movement Corridors for the Tricarinate Hill Turtle

NASA Astrophysics Data System (ADS)

Mondal, I.; Kumar, R. S.; Habib, B.; Talukdar, G.

2016-06-01

Habitat loss and the destruction of habitat connectivity can lead to species extinction by isolation of population. Identifying important habitat corridors to enhance habitat connectivity is imperative for species conservation by preserving dispersal pattern to maintain genetic diversity. Circuit theory is a novel tool to model habitat connectivity as it considers habitat as an electronic circuit board and species movement as a certain amount of current moving around through different resistors in the circuit. Most studies involving circuit theory have been carried out at small scales on large ranging animals like wolves or pumas, and more recently on tigers. This calls for a study that tests circuit theory at a large scale to model micro-scale habitat connectivity. The present study on a small South-Asian geoemydid, the Tricarinate Hill-turtle (Melanochelys tricarinata), focuses on habitat connectivity at a very fine scale. The Tricarinate has a small body size (carapace length: 127-175 mm) and home range (8000-15000 m2), with very specific habitat requirements and movement patterns. We used very high resolution Worldview satellite data and extensive field observations to derive a model of landscape permeability at 1 : 2,000 scale to suit the target species. Circuit theory was applied to model potential corridors between core habitat patches for the Tricarinate Hill-turtle. The modelled corridors were validated by extensive ground tracking data collected using thread spool technique and found to be functional. Therefore, circuit theory is a promising tool for accurately identifying corridors, to aid in habitat studies of small species.

Study on the oasis corridor landscape in the arid regions based on RS and GIS methods--application of Jinta Oasis, China.

PubMed

Ma, Ming-guo; Wang, Xue-mei; Cheng, Guo-dong

2003-03-01

The study on the oasis corridor landsape is a new hotspot in the ecological environment research in the arid regions. In oasis, main corridor landscape types include river, ditch, shelterbelt and road. This paper introduces the basic ecological effects of the corridor landscape on the transporting mass and energy and obstructing desert landscape expansion and incursion. Using Geographic Information System (GIS), we have researched the corridor distribution and its spatial relationship with other landscape types in the Jinta Oasis. Based on the dynamically monitoring on the landscape pattern change of the Jinta Oasis during the latter 10 years by using Remote Sensing (RS) and GIS, the driving functions of the corridors on this change have been analyzed in detail. The analysis results showed that all kinds of corridors' characteristics can be quantified by the indexes such as length and width, ratio of perimeter and area, density and non-heterogeneity. The total corridor length of Jinta Oasis is 1838.5 km and its density is 2.1 km/km2. The corridor density of the irrigation land, forest and resident area is maximal, which shows that affection degree of the oasis corridors on them is the most. The improvement of the corridors quality is one of the important driving factors on the irrigation land and so on. The organic combination of the RS and GIS technologies and landscape research methods would be an effective means for the corridor landscape research on arid region oasis.

Demand projections for the northeast corridor : financial analysis

DOT National Transportation Integrated Search

1976-06-30

This report describes the development and results of intercity travel demand projections by city-pair prepared for the Northeast Corridor financial analysis. In addition associated analyses of projected passenger volumes by station and of selected al...

Flat Branch monitoring project: stream water temperature and sediment responses to forest cutting in the riparian zone

Treesearch

Barton D. Clinton; James M. Vose; Dick L. Fowler

2010-01-01

Stream water protection during timber-harvesting activities is of primary interest to forest managers. In this study, we examine the potential impacts of riparian zone tree cutting on water temperature and total suspended solids. We monitored stream water temperature and total suspended solids before and after timber harvesting along a second-order tributary of the...

Integrating occupancy modeling and interview data for corridor identification: A case study for jaguars in Nicaragua

USGS Publications Warehouse

Zeller, K.A.; Nijhawan, S.; Salom-Perez, R.; Potosme, S.H.; Hines, J.E.

2011-01-01

Corridors are critical elements in the long-term conservation of wide-ranging species like the jaguar (Panthera onca). Jaguar corridors across the range of the species were initially identified using a GIS-based least-cost corridor model. However, due to inherent errors in remotely sensed data and model uncertainties, these corridors warrant field verification before conservation efforts can begin. We developed a novel corridor assessment protocol based on interview data and site occupancy modeling. We divided our pilot study area, in southeastern Nicaragua, into 71, 6. ??. 6 km sampling units and conducted 160 structured interviews with local residents. Interviews were designed to collect data on jaguar and seven prey species so that detection/non-detection matrices could be constructed for each sampling unit. Jaguars were reportedly detected in 57% of the sampling units and had a detection probability of 28%. With the exception of white-lipped peccary, prey species were reportedly detected in 82-100% of the sampling units. Though the use of interview data may violate some assumptions of the occupancy modeling approach for determining 'proportion of area occupied', we countered these shortcomings through study design and interpreting the occupancy parameter, psi, as 'probability of habitat used'. Probability of habitat use was modeled for each target species using single state or multistate models. A combination of the estimated probabilities of habitat use for jaguar and prey was selected to identify the final jaguar corridor. This protocol provides an efficient field methodology for identifying corridors for easily-identifiable species, across large study areas comprised of unprotected, private lands. ?? 2010 Elsevier Ltd.

Research/Evaluate Restoration of NE Oregon Streams: Effects of Livestock Exclosures (Corridor Fencing) on Riparian Vegetation, Stream Geomorphic Features and Fish Populations; Final Report 2002.

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

Kauffman, J. Boone

habitats and associated riparian functions; (2) a means of determining rates of aquatic habitat improvement; and (3) a basis for projecting future trends of habitat recovery. The proposed research is intended to provide an improved understanding of both the effects and effectiveness of a commonly used habitat enhancement approach in the upper Columbia River Basin. This is the exclusion of domestic livestock from streamside communities and streams via corridor fencing (exclosures). This final report is broken into three separate chapters. The first chapter covers the vegetation change associated with livestock exclusion. The second chapter focuses on the physical geomorphic changes to the streambank and channel. The final chapter covers the response of salmonids and warmwater fishes to livestock exclusion at the spatial scales of exclosures as is commonly constructed today. It is expected that this study will provide an important scientific basis, currently lacking, for understanding the ecological principles of restoration/enhancement of sustainable aquatic habitats for salmonids. Thus, the results of this work are likely to have important ramifications for habitat improvement projects within and beyond the general geographic region of northeastern Oregon.« less

Predicting the continuum between corridors and barriers to animal movements using Step Selection Functions and Randomized Shortest Paths.

PubMed

Panzacchi, Manuela; Van Moorter, Bram; Strand, Olav; Saerens, Marco; Kivimäki, Ilkka; St Clair, Colleen C; Herfindal, Ivar; Boitani, Luigi

2016-01-01

The loss, fragmentation and degradation of habitat everywhere on Earth prompts increasing attention to identifying landscape features that support animal movement (corridors) or impedes it (barriers). Most algorithms used to predict corridors assume that animals move through preferred habitat either optimally (e.g. least cost path) or as random walkers (e.g. current models), but neither extreme is realistic. We propose that corridors and barriers are two sides of the same coin and that animals experience landscapes as spatiotemporally dynamic corridor-barrier continua connecting (separating) functional areas where individuals fulfil specific ecological processes. Based on this conceptual framework, we propose a novel methodological approach that uses high-resolution individual-based movement data to predict corridor-barrier continua with increased realism. Our approach consists of two innovations. First, we use step selection functions (SSF) to predict friction maps quantifying corridor-barrier continua for tactical steps between consecutive locations. Secondly, we introduce to movement ecology the randomized shortest path algorithm (RSP) which operates on friction maps to predict the corridor-barrier continuum for strategic movements between functional areas. By modulating the parameter Ѳ, which controls the trade-off between exploration and optimal exploitation of the environment, RSP bridges the gap between algorithms assuming optimal movements (when Ѳ approaches infinity, RSP is equivalent to LCP) or random walk (when Ѳ → 0, RSP → current models). Using this approach, we identify migration corridors for GPS-monitored wild reindeer (Rangifer t. tarandus) in Norway. We demonstrate that reindeer movement is best predicted by an intermediate value of Ѳ, indicative of a movement trade-off between optimization and exploration. Model calibration allows identification of a corridor-barrier continuum that closely fits empirical data and demonstrates that RSP

Stream Sediment Sources in Midwest Agricultural Basins with Land Retirement along Channel.

PubMed

Williamson, T N; Christensen, V G; Richardson, W B; Frey, J W; Gellis, A C; Kieta, K A; Fitzpatrick, F A

2014-09-01

Documenting the effects of agricultural land retirement on stream-sediment sources is critical to identifying management practices that improve water quality and aquatic habitat. Particularly difficult to quantify are the effects from conservation easements that commonly are discontinuous along channelized streams and ditches throughout the agricultural midwestern United States. Our hypotheses were that sediment from cropland, retired land, stream banks, and roads would be discernible using isotopic and elemental concentrations and that source contributions would vary with land retirement distribution along tributaries of West Fork Beaver Creek in Minnesota. Channel-bed and suspended sediment were sampled at nine locations and compared with local source samples by using linear discriminant analysis and a four-source mixing model that evaluated seven tracers: In, P, total C, Be, Tl, Th, and Ti. The proportion of sediment sources differed significantly between suspended and channel-bed sediment. Retired land contributed to channel-bed sediment but was not discernible as a source of suspended sediment, suggesting that retired-land material was not mobilized during high-flow conditions. Stream banks were a large contributor to suspended sediment; however, the percentage of stream-bank sediment in the channel bed was lower in basins with more continuous retired land along the riparian corridor. Cropland sediments had the highest P concentrations; basins with the highest cropland-sediment contributions also had the highest P concentrations. Along stream reaches with retired land, there was a lower proportion of cropland material in suspended sediment relative to sites that had almost no land retirement, indicating less movement of nutrients and sediment from cropland to the channel as a result of land retirement. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

U.S.--Canada international mobility and trade corridor

DOT National Transportation Integrated Search

2002-05-01

Public and private stakeholders in Washington State and British Columbia established the international mobility and trade corridor (IMTC) partnership. The IMTC is a coalition of over 60 U.S. and Canadian business and government entities whose mission...

Integrated corridor management and advanced technologies for Florida.

DOT National Transportation Integrated Search

2012-11-01

Integrated Corridor Management (ICM) strategies have been proposed to address needs and provide solutions beyond those that can be provided when applying advanced strategies and technologies to one transportation subsystem at a time. The goal of this...

I-87/US 9 integrated corridor management plan.

DOT National Transportation Integrated Search

2015-11-01

This study evaluates the potentiality of developing an integrated freeway / arterial corridor : plan to improve overall operations of I-87 and US 9 (parallel arterial) by improving the methodology of : addressing recurring and non-recurring delays (i...

The Medial Extra-Sellar Corridor to the Cavernous Sinus: Anatomic Description and Clinical Correlation.

PubMed

Theodosopoulos, Philip V; Cebula, Helene; Kurbanov, Almaz; Cabero, Arnau Benet; Osorio, Joseph A; Zimmer, Lee A; Froelich, Sebastien C; Keller, Jeffrey T

2016-12-01

The zenith of surgical interest in the cavernous sinus peaked in the 1980s, as evidenced by reports of 10 surgical triangles that could access the contents of the lateral sellar compartment (LSC). However, these transcranial approaches later became marginalized, first by radiosurgery's popularity and lower morbidity, and then by clinical potential of endoscopic corridors noted in several qualitative studies. Our anatomic study, taking a contemporary look at the medial extra-sellar corridor, gives a detailed qualitative-quantitative analysis for its use with increasingly popular endoscopic endonasal approaches to the cavernous sinus. In 20 cadaveric specimens, we re-examined the anatomic landmarks of the medial corridor into the LSC with qualitative descriptions and measurements. An illustrative case highlights a recurrent symptomatic pituitary adenoma that invaded the cavernous sinus approached through the medial corridor. The corridor's shape varied from tetrahedron to hexahedron. Comparing right and left sides, width averaged 3.6 ± 4.5 mm and 4.0 ± 4.4 mm, and height averaged 2.3 mm and 2.1 mm, respectively. About 35% of sides showed ample space for access into the cavernous sinus. Our case report of successful outcome lends support for the safety and efficacy of this endoscopic approach. Our re-examination of this particular surgical access into the LSC refines the understanding of the medial extra-sellar corridor as a main endoscopic access route to this compartment. Achieving safe access to the contents of the LSC, this 11th triangle is clinically relevant and potentially superior for select lesions in this region. Copyright © 2016 Elsevier Inc. All rights reserved.

I-10 Corridor Coalition : a TPCB peer exchange

DOT National Transportation Integrated Search

2016-11-01

This report highlights key outcomes identified at the I-10 Corridor Coalition Peer Exchange held on June 2, 2016 in Phoenix, Arizona. This event was sponsored by the Transportation Planning Capacity Building (TPCB) Peer Program, which is jointl...

77 FR 74729 - Notice To Rescind a Notice of Intent and Draft Environmental Impact Statement: I-10 Corridor...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-17

... and Draft Environmental Impact Statement: I-10 Corridor Improvement Study; Maricopa County, AZ AGENCY..., Arizona. A NOI to prepare an EIS for the I-10 Corridor Improvement Study was published in the Federal..., Arizona. The I-10 Corridor is in or adjacent to the cities of Phoenix, Tempe, and Chandler, as well as the...

Perceptions of brachyfacial, mesofacial and dolichofacial individuals with regard to the buccal corridor in different facial types

PubMed Central

PITHON, Matheus Melo; da MATA, Kayure Rocha; ROCHA, Karina Silva; COSTA, Brenda do Nascimento; NEVES, Fernando; BARBOSA, George Caique Gouveia; COQUEIRO, Raildo da Silva

2014-01-01

Objective Evaluate the esthetic perception and attractiveness of the smile with regard to the buccal corridor in different facial types by brachyfacial, mesofacial and dolichofacial individuals. Material and Methods The image of a smiling individual with a mesofacial type of face was changed to create three different facial types with five different buccal corridors (2%, 10%, 15%, 22% and 28%). To achieve this effect, a photo editing software was used (Adobe Photoshop, Adobe Systems Inc, San Francisco, CA, EUA). The images were submitted to evaluators with brachyfacial, mesofacial and dolichofacial types of faces, who evaluated the degree of esthetic perception and attractiveness by means of a visual analog scale measuring 70 mm. The differences between evaluators were verified by the Mann-Whitney test. All statistics were performed with a confidence level of 95%. Results Brachyfacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2% as more attractive. Mesofacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2%, 10% and 15% as more attractive. Dolichofacial individuals perceived the mesofacial type of face with buccal corridor of 2% as more attractive. Evaluators of the female sex generally attributed higher scores than the male evaluators. Conclusion To achieve an enhanced esthetic smile it is necessary to observe the patient's facial type. The preference for narrow buccal corridors is an esthetic characteristic preferred by men and women, and wide buccal corridors are less attractive. PMID:25466472

Perceptions of brachyfacial, mesofacial and dolichofacial individuals with regard to the buccal corridor in different facial types.

PubMed

Pithon, Matheus Melo; Mata, Kayure Rocha da; Rocha, Karina Silva; Costa, Brenda do Nascimento; Neves, Fernando; Barbosa, George Caique Gouveia; Coqueiro, Raildo da Silva

2014-01-01

Evaluate the esthetic perception and attractiveness of the smile with regard to the buccal corridor in different facial types by brachyfacial, mesofacial and dolichofacial individuals. The image of a smiling individual with a mesofacial type of face was changed to create three different facial types with five different buccal corridors (2%, 10%, 15%, 22% and 28%). To achieve this effect, a photo editing software was used (Adobe Photoshop, Adobe Systems Inc, San Francisco, CA, EUA). The images were submitted to evaluators with brachyfacial, mesofacial and dolichofacial types of faces, who evaluated the degree of esthetic perception and attractiveness by means of a visual analog scale measuring 70 mm. The differences between evaluators were verified by the Mann-Whitney test. All statistics were performed with a confidence level of 95%. Brachyfacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2% as more attractive. Mesofacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2%, 10% and 15% as more attractive. Dolichofacial individuals perceived the mesofacial type of face with buccal corridor of 2% as more attractive. Evaluators of the female sex generally attributed higher scores than the male evaluators. To achieve an enhanced esthetic smile it is necessary to observe the patient's facial type. The preference for narrow buccal corridors is an esthetic characteristic preferred by men and women, and wide buccal corridors are less attractive.

An introduction to issues of habitat fragmentation relative to transportation corridors with special reference to high-speed rail (HSR)

NASA Astrophysics Data System (ADS)

de Santo, Robert S.; Smith, Dwight G.

1993-01-01

Potential environmental impacts on wildlife result from siting and construction (short-term impacts) and habitat removal and fragmentation (long-term impacts) as a consequence of transportation corridor construction. Especially in rural districts, wildlife migration corridors and dispersal orientation are altered or destroyed and wildlife populations and their gene pools are isolated. This significantly weakens the wildlife community. Prudent selection of construction corridors reduces fragmentation impacts by maximizing preserved fragment sizes, and by running parallel to, not through, natural areas. Corridor width determines the degree to which wildlife movement is restricted except that culverts, underpasses, overpasses, and one-way gates, can aid wildlife in cross movements. Minimum underpass dimensions for large wildlife should be no smaller than 14 ft×14 ft and should include natural substratum inverts. Rail corridors have four characteristics that minimize adverse environmental impacts. The railbed is dry, ballast fillters runoff, there is little runoff beyond the toe of slope, and drainage ditches serve to control sheet flow and erosion, sediment movement, and uncontrolled channel flow. Rail corridors usually occupy smaller land areas because they are narrower and are more feasible to elevate so as to allow free movement of wildlife across the corridor.

System requirement specification for the IH-10 Integrated Corridor Management System (ICMS) in San Antonio, Texas

DOT National Transportation Integrated Search

2008-03-31

This Requirements Specification Document (RSD) was developed under the project titled TransGuide Integrated Corridor Management Stage 1 as part of the United States Department of Transportation (USDOT) Integrated Corridor Management (ICM) p...

Landscape corridors can increase invasion by an exotic species and reduce diversity of native species

USDA-ARS?s Scientific Manuscript database

Although corridors have become commonplace in conservation to mitigate negative effects of habitat fragmentation, concerns persist that they may facilitate spread of invasive species. In a large-scale experiment, we measured effects of corridors on invasive fire ants, Solenopsis invicta, and on comm...

Dispersal corridors for plant species in the Poyang Lake Basin of southeast China identified by integration of phylogeographic and geospatial data.

PubMed

Fan, Dengmei; Sun, Zhixia; Li, Bo; Kou, Yixuan; Hodel, Richard G J; Jin, Zhinong; Zhang, Zhiyong

2017-07-01

Measuring the dispersal of wildlife through landscapes is notoriously difficult. Recently, the categorical least cost path algorithm that integrates population genetic data with species distribution models has been applied to reveal population connectivity. In this study, we use this method to identify the possible dispersal corridors of five plant species ( Castanopsis tibetana , Schima superba , Cyclocarya paliurus , Sargentodoxa cuneata , Eomecon chionantha ) in the Poyang Lake Basin (PLB, largely coinciding with Jiangxi Province), China, in the late Quaternary. The results showed that the strongest population connectivity for the five species occurred in the Wuyi Mountains and the Yu Mountains of the eastern PLB (East Corridor) during the late Quaternary. In the western PLB, populations of the five species were connected by the Luoxiao Mountains and the Jiuling Mountains (West Corridor) but with a lower degree of connectivity. There were some minor connections between the eastern and the western populations across the Gannan Hills. When the corridors of five species were overlaid, the East Corridor and the West Corridor were mostly shared by multiple species. These results indicate that plant species in the PLB could have responded to the Quaternary climate changes by moving along the East Corridor and the West Corridor. Given that dispersal corridors have seldom been considered in the governmental strategies of biodiversity conservation in the PLB, preserving and restoring natural vegetation along these corridors should be prioritized to mitigate the effects of anthropogenic climate change by facilitating migration of plant species and other biota.

Temporal variation in the importance of a dominant consumer to stream nutrient cycling

DOE PAGES

Griffiths, Natalie A.; Hill, Walter

2014-06-19

Animal excretion can be a significant nutrient flux within ecosystems, where it supports primary production and facilitates microbial decomposition of organic matter. The effects of excretory products on nutrient cycling have been documented for various species and ecosystems, but temporal variation in these processes is poorly understood. We examined variation in excretion rates of a dominant grazing snail, Elimia clavaeformis, and its contribution to nutrient cycling, over the course of 14 months in a well-studied, low-nutrient stream (Walker Branch, east Tennessee, USA). Biomass-specific excretion rates of ammonium varied over twofold during the study, coinciding with seasonal changes in food availabilitymore » (measured as gross primary production) and water temperature (multiple linear regression, R 2 = 0.57, P = 0.053). The contribution of ammonium excretion to nutrient cycling varied with seasonal changes in both biological (that is, nutrient uptake rate) and physical (that is, stream flow) variables. On average, ammonium excretion accounted for 58% of stream water ammonium concentrations, 26% of whole-stream nitrogen demand, and 66% of autotrophic nitrogen uptake. Phosphorus excretion by Elimia was contrastingly low throughout the year, supplying only 1% of total dissolved phosphorus concentrations. The high average N:P ratio (89:1) of snail excretion likely exacerbated phosphorus limitation in Walker Branch. To fully characterize animal excretion rates and effects on ecosystem processes, multiple measurements through time are necessary, especially in ecosystems that experience strong seasonality.« less

Temporal variation in the importance of a dominant consumer to stream nutrient cycling

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

Griffiths, Natalie A.; Hill, Walter

Animal excretion can be a significant nutrient flux within ecosystems, where it supports primary production and facilitates microbial decomposition of organic matter. The effects of excretory products on nutrient cycling have been documented for various species and ecosystems, but temporal variation in these processes is poorly understood. We examined variation in excretion rates of a dominant grazing snail, Elimia clavaeformis, and its contribution to nutrient cycling, over the course of 14 months in a well-studied, low-nutrient stream (Walker Branch, east Tennessee, USA). Biomass-specific excretion rates of ammonium varied over twofold during the study, coinciding with seasonal changes in food availabilitymore » (measured as gross primary production) and water temperature (multiple linear regression, R 2 = 0.57, P = 0.053). The contribution of ammonium excretion to nutrient cycling varied with seasonal changes in both biological (that is, nutrient uptake rate) and physical (that is, stream flow) variables. On average, ammonium excretion accounted for 58% of stream water ammonium concentrations, 26% of whole-stream nitrogen demand, and 66% of autotrophic nitrogen uptake. Phosphorus excretion by Elimia was contrastingly low throughout the year, supplying only 1% of total dissolved phosphorus concentrations. The high average N:P ratio (89:1) of snail excretion likely exacerbated phosphorus limitation in Walker Branch. To fully characterize animal excretion rates and effects on ecosystem processes, multiple measurements through time are necessary, especially in ecosystems that experience strong seasonality.« less

Integrated corridor management : phase I, concept development and foundational research. Task 3.4, identify integrated corridor management institutional strategies and administration

DOT National Transportation Integrated Search

2006-04-12

Task 3 involves overall foundational research to further the understanding of various aspects of Integrated Corridor Management (ICM) and to identify integration issues needed to evaluate the feasibility of the ICM initiative. The focus of Task 3.4 a...

Vault Area (original section), south corridor, looking west Fort ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Vault Area (original section), south corridor, looking west - Fort McNair, Film Store House, Fort Lesley J. McNair, P Street between Third & Fourth Streets, Southwest, Washington, District of Columbia, DC

MOSAIC : Model of Sustainability and Integrated Corridors : [research summary].

DOT National Transportation Integrated Search