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Water Flow and Beaver Habitat in Grand Teton National Park: Adaptation to Climate Change

Thu, 2017-11-09 09:51

Beavers are a keystone species in Grand Teton National Park and are critical to the aquatic and terrestrial landscape. Modifications to their habitat by climate change impact multiple species. This study is designed to examine the current distribution and habitat of beavers in Grand Teton National Park and analyze the alterations to this distribution and habitat based on climate change. Field and aerial surveys were completed to determine the distribution of beaver colonies in Grand Teton National Park. Beaver habitat was constructed by integrating field surveys of vegetation, soils and hydrologic characteristics with satellite imagery classification. A model of climate change was utilized in an effort to distinguish potentially different rates of temperature and precipitation change into the 21st century. The results of the climate model were then integrated into a watershed assessment model to determine stream flow in the Snake River basin. The decreasing flow rates are critical to beaver habitat for cottonwoods and willow species and beaver settlement and movement and will limit their movement. In addition, the Snake River below Jackson Lake Dam is regulated for irrigation into Idaho and the decreasing flows on the Snake River below the Jackson Lake Dam will also impact water availability for beaver habitats. Decreases in precipitation availability will increase irrigation demand causing changes in the Snake River flow patterns. Management conflicts exist between preserving and maintaining beaver habitat in the national park and meeting the irrigation

Simulating Expected Changes in Pollinator Resources as a Function of Climate Change

Thu, 2017-11-09 09:51

Ecological effects of climate change can include advancement of spring events, shifts in species distribution patterns, and phenological changes. Studying these responses under field conditions can require decades of research. In 2010, we established an experimental field study designed to mimic the effects of predicted climate change using snow removal and passive heating in montane meadows. Here, we use this same experimental set-up to examine nectar production relative to pollinator emergence in two important nectar sources: Arrowleaf Balsamroot (Balsamorhiza sagitatta) and Wild Buckwheat (Eriogonum umbellatum). Preliminary results indicate that there was lower nectar volume for Balsamorhiza sagitatta in the heating compared to either the control or snow removal. The heating + snow removal was also lower in nectar volume than snow removal only. Preliminary results for Eriogonum umbellatum showed a lower sugar content in the control as compared to the heating + snow removal.

Kelly Warm Springs Historical Data Summary: Progress Report

Thu, 2017-11-09 09:51

Kelly Warm Springs is a unique geological feature located within Grand Teton National Park, Wyoming. The Kelly Warm Springs area is used extensively by park wildlife, for recreation by park visitors, and is a place of educational interest. It has also been the site of historic non-native fish releases. The current work was initiated to gather historical information and to begin systematic documentation of temperatures in and around Kelly Warm Springs. Historic information that was not published but considered valid was included. Non-native fish presence was first documented in the 1960s. Concerns about non-native fish and habitat loss for native species were discussed by researchers in the 1980s. The temperature ranges recorded at several sites October – December 2014 approached 0oC at the lower section of the outflow channel, but remained above 20oC in the spring pond. While these range below the preferred temperature range for goldfish, research has documented survival in near zero temperatures. All sites located below Mormon Row where temperature loggers were initially deployed were either dewatered or frozen by mid-November.

Measuring the Morphology and Dynamics of the Snake River by Remote Sensing

Thu, 2017-11-09 09:51

The Snake River is a prominent, central feature of Grand Teton National Park, and this dynamic fluvial system maintains diverse habitats while actively shaping the landscape. Although the riparian corridor is relatively pristine, the Snake River is by no means free from anthropogenic influences: streamflows have been regulated since 1907 by Jackson Lake Dam. Among dam-controlled rivers in the western U.S., the Snake River is unique in that tributaries entering below the dam supply sufficient coarse bed material to produce a braided morphology. As a result of tributary inputs, sediment flux along the Snake River has been relatively unaffected by Jackson Lake Dam, but flow regulation has reduced the magnitude and altered the timing of streamflows. In this study we are coupling an annual image time series with extensive field surveys to document channel changes occurring on the Snake River. Our objective is to quantify how snowmelt runoff events and flow management strategies influence patterns of sediment transfer and storage throughout the river system, with a particular focus on tributary junctions. More specifically, we are using the image sequence to identify areas of erosion and deposition and hence infer the sediment flux associated with the observed changes in channel morphology. This analysis will improve our understanding of the river’s response to flow management and enable us to generate hypotheses as to how the system might adapt to future anthropogenic and/or climate-driven alterations in streamflow and sediment supply. In addition, our research on the Snake River involves an ongoing assessment of the potential to measure the morphology and dynamics of large, complex rivers via remote sensing. A new aspect of this investigation involves estimating flow velocities from hyperspectral images that capture the texture of the water surface. Extensive field measurements of velocity and water surface roughness are being used to develop this innovative approach and thus increase the amount of river information that can be inferred via remote sensing.

Shallow Seismic Investigation of the Teton Fault

Thu, 2017-11-09 09:51

Preliminary results from seismic data collected at two sites on the Teton fault reveal shallow sub-surface fault structure and a basis for evaluating the post-glacial faulting record in greater detail. These new data include high-resolution shallow 2D seismic refraction and Interferometric Multi-Channel Analysis of Surface Waves (IMASW) (O’Connell and Turner 2010) depth-averaged shear wave velocity (Vs). The Teton fault, a down-to-the east normal fault, is expressed as a distinct topographic escarpment along the base of the eastern front of the Teton Range in Wyoming. The average fault scarp height cut into deglacial surfaces in several similar valleys and an assumed 14,000 yr BP deglaciation indicates an average postglacial offset rate of 0.82 m/ka (Thackray and Staley, in review). Because the fault is located almost entirely within Grand Teton National Park (GTNP), and in terrain that is remote and difficult to access, very few subsurface studies have been used to evaluate the fault. As a result, many uncertainties exist in the present characterization of along-strike slip rate, down-dip geometry, and rupture history, among other parameters. Additionally, questions remain about the fault dip at depth. Shallow seismic data were collected at two locations on the Teton fault scarp to (1) use a non-destructive, highly portable and cost-effective data collection system to image and characterize the Teton fault, (2) use the data to estimate vertical offsets of faulted bedrock and sediment, and (3) estimate fault dip in the shallow subsurface. Vs data were also collected at three GTNP facility structures to provide measured 30 m depth-averaged Vs (Vs30) for each site. Seismic data were collected using highly portable equipment packed into each site on foot. The system utilizes a sensor line 92 m long that includes 24 geophones (channels) at 4 m intervals. At both the Taggart Lake and String Lake sites, P-wave refraction data were collected spanning the fault scarp and perpendicular to local fault strike, as well as IMASW Vs seismic lines positioned on the hanging wall to provide Vs vs. Depth profiles crossing and perpendicular to the refraction survey lines. The Taggart Lake and String Lake 2D P-wave refraction profile and IMASW Vs plots reveal buried velocity structure that is vertically offset by the Teton fault. At Taggart Lake, we interpret the velocity horizon to be the top of dense glacial sediment (possibly compacted till), which is overlain by younger, slower, sediments. This surface is offset ~13 m (down-to-the-east) across the Teton fault. The vertical offset is in agreement with the measured height of the corresponding topographic scarp (~12 - 15 m). Geomorphic analysis of EarthScope (2008) LiDAR reveals small terraces, slope inflections and an abandoned channel on the footwall side of the scarp. At String Lake, the shallow buried velocity structure is inferred as unconsolidated alluvium (till, colluvium, alluvium); this relatively low velocity zone (<1000m/s) is spatially coincident with the center of a gully, and appears to be vertically offset 10 – 14 m across the Teton fault. Scarp heights adjacent to the gully to the north and south are ~35 m. Final interpretations are forthcoming pending additional data processing and analysis. This project was funded by a grant awarded by the University of Wyoming-National Park Service Research Center.

Front Matter and Table of Contents

Thu, 2017-11-09 09:51

This entry contains the front cover and front matter.

Permutative nonnegative matrices with prescribed spectrum

Tue, 2017-11-07 07:25

An n × n permutative matrix is a matrix in which every row is a permutation of the first row. In this paper, the result given by Paparella in [P. Paparella. Realizing Suleimanova spectra via permutative matrices. Electron. J. Linear Algebra, 31:306–312, 2016.] is extended to a more general lists of real and complex numbers, and a negative partial answer to a question posed by him is given.

On the construction of Q-controllable graphs

Sun, 2017-10-15 08:53

A connected graph is called Q-controllable if its signless Laplacian eigenvalues are mutually distinct and main. Two graphs G and H are said to be Q-cospectral if they share the same signless Laplacian spectrum. In this paper, infinite families of Q-controllable graphs are constructed, by using the operator of rooted product introduced by Godsil and McKay. In the process, innitely many non-isomorphic Q-cospectral graphs are also constructed, especially, including those graphs whose signless Laplacian eigenvalues are mutually distinct.

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