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Articles 1111 - 1140 of 1586
Full-Text Articles in Physical Sciences and Mathematics
Application Of A Routing Model For Detecting Channel Flow Changes With Minimal Data, Jozsef Szilagyi, Nicholas Pinter, Rob Venczel
Application Of A Routing Model For Detecting Channel Flow Changes With Minimal Data, Jozsef Szilagyi, Nicholas Pinter, Rob Venczel
School of Natural Resources: Faculty Publications
No abstract provided.
Comment On "Comparison Of 15 Evaporation Models Applied To A Small Mountain Lake In The Northeastern Usa", Jozsef Szilagyi
Comment On "Comparison Of 15 Evaporation Models Applied To A Small Mountain Lake In The Northeastern Usa", Jozsef Szilagyi
School of Natural Resources: Faculty Publications
No abstract provided.
Riparian Zone Evapotranspiration From Diurnal Groundwater-Level Fluctuations, Zoltan Gribovszki, Peter Kalicz, Jozsef Szilagyi, Mihaly Kucsara
Riparian Zone Evapotranspiration From Diurnal Groundwater-Level Fluctuations, Zoltan Gribovszki, Peter Kalicz, Jozsef Szilagyi, Mihaly Kucsara
School of Natural Resources: Faculty Publications
No abstract provided.
Rationale For A Permanent Seismic Network In The U.S. Central Plains Utilizing U.S. Array, Stephen S. Gao, Tina M. Niemi, Ross A. Black, Kelly H. Liu, Raymond R. Anderson, Robert M. Joeckel, Robert W. Busby, John Taber
Rationale For A Permanent Seismic Network In The U.S. Central Plains Utilizing U.S. Array, Stephen S. Gao, Tina M. Niemi, Ross A. Black, Kelly H. Liu, Raymond R. Anderson, Robert M. Joeckel, Robert W. Busby, John Taber
School of Natural Resources: Faculty Publications
No abstract provided.
Evapotranspiration Calculation On The Basis Of The Riparian Zone Water Balance, Zoltan Gribovszki, Peter Kalicz, Mihaly Kucsara, Jozsef Szilagyi, Peter Vig
Evapotranspiration Calculation On The Basis Of The Riparian Zone Water Balance, Zoltan Gribovszki, Peter Kalicz, Mihaly Kucsara, Jozsef Szilagyi, Peter Vig
School of Natural Resources: Faculty Publications
No abstract provided.
Remediating Explosive-Contaminated Groundwater By In Situ Redox Manipulation (Isrm) Of Aquifer Sediments, H.K. Boparai, Steven Comfort, Patrick J. Shea, J.E. Szecsody
Remediating Explosive-Contaminated Groundwater By In Situ Redox Manipulation (Isrm) Of Aquifer Sediments, H.K. Boparai, Steven Comfort, Patrick J. Shea, J.E. Szecsody
School of Natural Resources: Faculty Publications
In situ chemical reduction of clays and iron oxides in subsurface environments is an emerging technology for treatment of contaminated groundwater. Our objective was to determine the efficacy of dithionite-reduced sediments from the perched Pantex Aquifer (Amarillo, TX) to abiotically degrade the explosives RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), HMX (octahydro-1,3,5,7-tetranitro- 1,3,5,7-tetrazocine), and TNT (2,4,6-trinitrotoluene). The effects of dithionite/buffer concentrations, sediments-solution ratios, and the contribution of Fe(II) were evaluated in batch experiments. Results showed that reduced Pantex sediments were highly effective in degrading all three high explosives. Degradation rates increased with increasing dithionite/buffer concentrations and soil to solution ratios (1:80–1:10 w/v). When Fe(II) was …
Interpretation And Evaluation Of Combined Measurement Techniques For Soil Co2 Efflux: Discrete Surface Chambers And Continuous Soil Co2 Concentration Probes, Diego Andrés Riveros-Iregui, Brian L. Mcglynn, Howard E. Epstein, Daniel L. Welsch
Interpretation And Evaluation Of Combined Measurement Techniques For Soil Co2 Efflux: Discrete Surface Chambers And Continuous Soil Co2 Concentration Probes, Diego Andrés Riveros-Iregui, Brian L. Mcglynn, Howard E. Epstein, Daniel L. Welsch
School of Natural Resources: Faculty Publications
Soil CO2 efflux is a large respiratory flux from terrestrial ecosystems and a critical component of the global carbon (C) cycle. Lack of process understanding of the spatiotemporal controls on soil CO2 efflux limits our ability to extrapolate from fluxes measured at point scales to scales useful for corroboration with other ecosystem level measures of C exchange. Additional complications are introduced by the effects of soil water content seasonality and rainfall on the performance of measurement techniques. In this paper we present measurements of soil CO2 efflux made at two contrasting sites within a characteristic subalpine forest …
Vertical Profile And Temporal Variation Of Chlorophyll In Maize Canopy: Quantitative “Crop Vigor” Indicator By Means Of Reflectance-Based Techniques, Verónica Ciganda, Anatoly A. Gitelson, James S. Schepers
Vertical Profile And Temporal Variation Of Chlorophyll In Maize Canopy: Quantitative “Crop Vigor” Indicator By Means Of Reflectance-Based Techniques, Verónica Ciganda, Anatoly A. Gitelson, James S. Schepers
School of Natural Resources: Faculty Publications
Chlorophyll (Chl) content is among the most important crop biophysical characteristics. Chlorophyll can be related to photosynthetic capacity, thus, productivity, developmental stage, and canopy stresses. The objective of this study was to quantify and characterize the temporal variation of Chl content in the vertical profile of maize (Zea mays L.) canopies by means of a reflectance-based, nondestructive methodology. A recently developed technique that relates leaf reflectance with leaf pigment content has been used for accurate leaf Chl estimation. The technique employs reflectance in two spectral bands: in the red edge (720-730 nm) and in the near infrared (770-800 nm). …
Application Of Spectral Remote Sensing For Agronomic Decisions, J. L. Hatfield, Anatoly A. Gitelson, James S. Schepers, C. L. Walthall
Application Of Spectral Remote Sensing For Agronomic Decisions, J. L. Hatfield, Anatoly A. Gitelson, James S. Schepers, C. L. Walthall
School of Natural Resources: Faculty Publications
Remote sensing has provided valuable insights into agronomic management over the past 40 yr. The contributions of individuals to remote sensing methods have lead to understanding of how leaf reflectance and leaf emittance changes in response to leaf thickness, species, canopy shape, leaf age, nutrient status, and water status. Leaf chlorophyll and the preferential absorption at different wavelengths provides the basis for utilizing reflectance with either broad-band radiometers typical of current satellite platforms or hyperspectral sensors that measure reflectance at narrow wavebands. Understanding of leaf reflectance has lead to various vegetative indices for crop canopies to quantify various agronomic parameters, …
Variability In Soil Respiration Across Riparian-Hillslope Transitions, Vincent J. Pacific, Brian L. Mcglynn, Diego Andrés Riveros-Iregui, Daniel L. Welsch, Howard E. Epstein
Variability In Soil Respiration Across Riparian-Hillslope Transitions, Vincent J. Pacific, Brian L. Mcglynn, Diego Andrés Riveros-Iregui, Daniel L. Welsch, Howard E. Epstein
School of Natural Resources: Faculty Publications
The spatial and temporal controls on soil CO2 production and surface CO2 efflux have been identified as outstanding gaps in our understanding of carbon cycling. We investigated both across two riparian-hillslope transitions in a subalpine catchment, northern Rocky Mountains, Montana. Riparian-hillslope transitions provide ideal locations for investigating the controls on soil CO2 dynamics due to strong, natural gradients in the factors driving respiration, including soil water content (SWC) and soil temperature. We measured soil air CO2 concentrations (20 and 50 cm), surface CO2 efflux, soil temperature, and SWC at eight locations. We investigated (1) how …
Nondestructive Estimation Of Leaf Chlorophyll Content In Grapes, Mark Steele, Anatoly A. Gitelson, Donald Rundquist
Nondestructive Estimation Of Leaf Chlorophyll Content In Grapes, Mark Steele, Anatoly A. Gitelson, Donald Rundquist
School of Natural Resources: Faculty Publications
Leaf chlorophyll content provides valuable information about the physiological status of plants, and there is a need for accurate, efficient, practical methodologies to estimate this biophysical parameter. Reflectance measurement is a means of quickly and nondestructively assessing, in situ, the chlorophyll content in leaves. The objective of this study was to develop a precise, efficient, nondestructive technique to estimate leaf total chlorophyll (Chl) content in grapes. A relationship was established between Chl content and the red-edge chlorophyll index, based on reflectances in the red-edge (710–720 nm) and near-infrared (755–765 nm) spectral ranges, and the algorithm for Chl retrieval was calibrated. …
The Risk Of Flawed Inference In Evolutionary Studies When Detectability Is Less Than One, Olivier Gimenez, Anne Viallefont, Anne Charmantier, Roger Pradel, Emmanuelle Cam, Charles R. Brown, Mark D. Anderson, Mary Bomberger Brown, Rita Covas, Jean-Michel Gaillard2
The Risk Of Flawed Inference In Evolutionary Studies When Detectability Is Less Than One, Olivier Gimenez, Anne Viallefont, Anne Charmantier, Roger Pradel, Emmanuelle Cam, Charles R. Brown, Mark D. Anderson, Mary Bomberger Brown, Rita Covas, Jean-Michel Gaillard2
School of Natural Resources: Faculty Publications
Addressing evolutionary questions in the wild remains a challenge. It is best done by monitoring organisms from birth to death, which is very difficult in part because individuals may or may not be resighted or recaptured. Although the issue of uncertain detection has long been acknowledged in ecology and conservation biology, in evolutionary studies of wild populations it is often assumed that detectability is perfect. We argue that this assumption may lead to flawed inference. We demonstrate that the form of natural selection acting on body mass of sociable weavers is altered and that the rate of senescence of roe …
Fish Distributions And Nutrient Cycling In Streams: Can Fish Create Biogeochemical Hotspots?, Peter B. Mcintyre, Alexander S. Flecker, Michael J. Vanni, James M. Hood, Brad W. Taylor, Steven A. Thomas
Fish Distributions And Nutrient Cycling In Streams: Can Fish Create Biogeochemical Hotspots?, Peter B. Mcintyre, Alexander S. Flecker, Michael J. Vanni, James M. Hood, Brad W. Taylor, Steven A. Thomas
School of Natural Resources: Faculty Publications
Rates of biogeochemical processes often vary widely in space and time, and characterizing this variation is critical for understanding ecosystem functioning. In streams, spatial hotspots of nutrient transformations are generally attributed to physical and microbial processes. Here we examine the potential for heterogeneous distributions of fish to generate hotspots of nutrient recycling. We measured nitrogen (N) and phosphorus (P) excretion rates of 47 species of fish in an N-limited Neotropical stream, and we combined these data with population densities in each of 49 stream channel units to estimate unit- and reach-scale nutrient recycling. Species varied widely in rates of N …
2008 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Joel G. Jorgensen
2008 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Joel G. Jorgensen
School of Natural Resources: Faculty Publications
This document reports on our monitoring, research, management, and outreach activities during the past 12 months. The report was prepared to inform our partners and funding agencies of our activities and to provide a preliminary summary of results. These data analyses are not final and should be treated as such when citing information, data, or analyses found in this document.
The Interior Least Tern (Sternula antillarum athallassos) is a state and federal endangered species; it was first listed in 1985. The Piping Plover (Charadrius melodus) is a state and federal threatened species; it was also first …
Terrapene Ornata (Ornate Box Turtle) Predation On Cliff Swallows, Mary Bomberger Brown, Charles R. Brown
Terrapene Ornata (Ornate Box Turtle) Predation On Cliff Swallows, Mary Bomberger Brown, Charles R. Brown
School of Natural Resources: Faculty Publications
During a 25-year study of Cliff Swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, we observed Terrapene ornata prey, or attempt to prey, on swallows. On one occasion as large numbers of birds flushed and hit the net, the weight of the birds pulled the net down to ground level. One T. ornata, which was seen regularly at the colony, approached one adult Cliff Swallow that was very low in the net and killed it by biting and eating its head. After killing the bird, the turtle walked away carrying the head.
Experimental Inoculation Of House Sparrows (Passer Domesticus) With Buggy Creek Virus, Kathryn P. Huyvaert, Amy T. Moore, Nicholas A. Panella, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown
Experimental Inoculation Of House Sparrows (Passer Domesticus) With Buggy Creek Virus, Kathryn P. Huyvaert, Amy T. Moore, Nicholas A. Panella, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown
School of Natural Resources: Faculty Publications
We performed experimental inoculations of house sparrows (Passer domesticus) with Buggy Creek virus (BCRV), a poorly known alphavirus (Togaviridae) vectored primarily by the swallow bug (Hemiptera: Cimicidae: Oeciacus vicarius) that is an ectoparasite of the cliff swallow (Petrochelidon pyrrhonota) and house sparrow. Viremias were detected by plaque assay in two of six birds on days 1–3 postinoculation; viremia was highest on day 2. Viral RNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) in blood of six of 12 birds ranging from day 1 to day 15 postinoculation. Infectious BCRV was detected in …
Estimation Of Net Ecosystem Carbon Exchange For The Conterminous United States By Combining Modis And Ameriflux Data, Jingfeng Xiao, Qianlai Zhuang, Dennis D. Baldocchi, Beverly E. Law, Andrew D. Richardson, Jiquan Chen, Ram Oren, Gregory Starr, Asko Noormets, Siyan Ma, Shashi Verma, Sonia Wharton, Steven C. Wofsy, Paul V. Bolstad, Sean P. Burns, David R. Cook, Peter S. Curtis, Bert G. Drake, Matthias Falk, Marc L. Fischer, David R. Foster, Lianhong Gu, Julian L. Hadley, David Y. Hollinger, Gabriel G. Katul, Marcy Litvak, Timothy A. Martin, Roser Matamala, Steve Mcnulty, Tilden P. Meyers, Russell K. Monson, J. William Munger, Walter C. Oechel, Kyaw Tha Paw U, Hans Peter Schmid, Russell L. Scott, Ge Sun, Andrew E. Suyker, Margaret S. Torn
Estimation Of Net Ecosystem Carbon Exchange For The Conterminous United States By Combining Modis And Ameriflux Data, Jingfeng Xiao, Qianlai Zhuang, Dennis D. Baldocchi, Beverly E. Law, Andrew D. Richardson, Jiquan Chen, Ram Oren, Gregory Starr, Asko Noormets, Siyan Ma, Shashi Verma, Sonia Wharton, Steven C. Wofsy, Paul V. Bolstad, Sean P. Burns, David R. Cook, Peter S. Curtis, Bert G. Drake, Matthias Falk, Marc L. Fischer, David R. Foster, Lianhong Gu, Julian L. Hadley, David Y. Hollinger, Gabriel G. Katul, Marcy Litvak, Timothy A. Martin, Roser Matamala, Steve Mcnulty, Tilden P. Meyers, Russell K. Monson, J. William Munger, Walter C. Oechel, Kyaw Tha Paw U, Hans Peter Schmid, Russell L. Scott, Ge Sun, Andrew E. Suyker, Margaret S. Torn
School of Natural Resources: Faculty Publications
Eddy covariance flux towers provide continuous measurements of net ecosystem carbon exchange (NEE) for a wide range of climate and biome types. However, these measurements only represent the carbon fluxes at the scale of the tower footprint. To quantify the net exchange of carbon dioxide between the terrestrial biosphere and the atmosphere for regions or continents, flux tower measurements need to be extrapolated to these large areas. Here we used remotely sensed data from the Moderate Resolution Imaging Spectrometer (MODIS) instrument on board the National Aeronautics and Space Administration’s (NASA) Terra satellite to scale up AmeriFlux NEE measurements to the …
New Findings About The Complementary Relationship-Based Evaporation Estimation Methods, Jozsef Szilagyi, Janos Jozsa
New Findings About The Complementary Relationship-Based Evaporation Estimation Methods, Jozsef Szilagyi, Janos Jozsa
School of Natural Resources: Faculty Publications
No abstract provided.
Equilibrium Sampling Used To Monitor Malodors In A Swine Waste Lagoon, Rezaul Mahmood
Equilibrium Sampling Used To Monitor Malodors In A Swine Waste Lagoon, Rezaul Mahmood
School of Natural Resources: Faculty Publications
No abstract provided.
Meso-Scale Weather And Climate Observations In Kentucky For Societal Benefit, Rezaul Mahmood
Meso-Scale Weather And Climate Observations In Kentucky For Societal Benefit, Rezaul Mahmood
School of Natural Resources: Faculty Publications
No abstract provided.
A Coupled Mm5-Noah And Surface Model-Based Assessment Of Sensitivity Of Planetary Boundary Layer Variables To Anomalous Soil Moisture Conditions, Rezaul Mahmood
A Coupled Mm5-Noah And Surface Model-Based Assessment Of Sensitivity Of Planetary Boundary Layer Variables To Anomalous Soil Moisture Conditions, Rezaul Mahmood
School of Natural Resources: Faculty Publications
No abstract provided.
Geologic Map Of The O'Neill 1º X 2º Quadrangle, Nebraska, With Configuration Maps Of Surfaces Of Formations, Robert Diffendal, Jr., Michael R. Voorhies, E. Jane Voorhies, H. E. Lagarry, C. L. Timperley, M. E. Perkins
Geologic Map Of The O'Neill 1º X 2º Quadrangle, Nebraska, With Configuration Maps Of Surfaces Of Formations, Robert Diffendal, Jr., Michael R. Voorhies, E. Jane Voorhies, H. E. Lagarry, C. L. Timperley, M. E. Perkins
School of Natural Resources: Faculty Publications
SCALE 1:250,000
CONTOUR INTERVAL 200 FEET
Geology mapped principally from 1991-2000 by RFD, M.RV, E.JV, H. LG , and C.LT
Editing and layout by R.F. Diffendal, Jr. and D. Ebbeka
Map production by J. Nothwehr and L. Howard
Revised slightly 6 January 2009, 20 July 2010, 5 October 2010, 10 September 2012.
Chinese Liver Flukes In Latrine Sediments From Wong Nim’S Property, San Bernardino, California: Archaeoparasitology Of The Caltrans District Headquarters (Galley Proofs), Karl J. Reinhard, Adauto Araújo, Luciana Sianto, Julia G. Costello, Karen Swope
Chinese Liver Flukes In Latrine Sediments From Wong Nim’S Property, San Bernardino, California: Archaeoparasitology Of The Caltrans District Headquarters (Galley Proofs), Karl J. Reinhard, Adauto Araújo, Luciana Sianto, Julia G. Costello, Karen Swope
School of Natural Resources: Faculty Publications
Parasitological analysis of 5 sediment samples from latrine deposits spanning the time period from about 1880 to the 1930s are presented. Two sediment samples are from a latrine used by European-Americans. Three sediment samples are from latrines used by Chinese-Americans on the property of Wong Nim, an important member of the Chinese community. Two of the Chinese latrines were positive for human parasites. The human parasites encountered include the human whipworm (Trichuris trichiura), the giant intestinal roundworm (Ascaris lumbricoides, c.f.), and the Chinese liver fluke (Clonorchis sinensis). Evidence of the liver fluke is especially …
Power Laws, Discontinuities And Regional City Size Distributions, Ahjond S. Garmestan, Craig R. Allen, Colin M. Gallagher
Power Laws, Discontinuities And Regional City Size Distributions, Ahjond S. Garmestan, Craig R. Allen, Colin M. Gallagher
School of Natural Resources: Faculty Publications
Urban systems are manifestations of human adaptation to the natural environment. City size distributions are the expression of hierarchical processes acting upon urban systems. In this paper, we test the entire city size distributions for the southeastern and southwestern United States (1990), as well as the size classes in these regions for power law behavior. We interpret the differences in the size of the regional city size distributions as the manifestation of variable growth dynamics dependent upon city size. Size classics in the city size distributions are snapshots of stable states within urban systems in flux.
Unresolved Issues With The Assessment Of Multidecadal Global Land Surface Temperature Trends, Roger A. Pielke Sr., Christopher A. Davey, Dev Niyogi, Souleymane Fall, Jesse Steinweg-Woods, Ken Hubbard, Xiaomao Lin, Ming Cai, Young-Kwon Lim, Hong Li, John Nielsen-Gammon, Kevin Gallo, Robert Hale, Rezaul Mahmood, Stuart Foster, Richard T. Mcnider, Peter Blanken
Unresolved Issues With The Assessment Of Multidecadal Global Land Surface Temperature Trends, Roger A. Pielke Sr., Christopher A. Davey, Dev Niyogi, Souleymane Fall, Jesse Steinweg-Woods, Ken Hubbard, Xiaomao Lin, Ming Cai, Young-Kwon Lim, Hong Li, John Nielsen-Gammon, Kevin Gallo, Robert Hale, Rezaul Mahmood, Stuart Foster, Richard T. Mcnider, Peter Blanken
School of Natural Resources: Faculty Publications
This paper documents various unresolved issues in using surface temperature trends as a metric for assessing global and regional climate change. A series of examples ranging from errors caused by temperature measurements at a monitoring station to the undocumented biases in the regionally and globally averaged time series are provided. The issues are poorly understood or documented and relate to micrometeorological impacts due to warm bias in nighttime minimum temperatures, poor siting of the instrumentation, effect of winds as well as surface atmospheric water vapor content on temperature trends, the quantification of uncertainties in the homogenization of surface temperature data, …
Reinterpreting The Pollen Data From Dos Cabezas, Karl J. Reinhard, Vaughn M. Bryant, Sheila D. Vinton
Reinterpreting The Pollen Data From Dos Cabezas, Karl J. Reinhard, Vaughn M. Bryant, Sheila D. Vinton
School of Natural Resources: Faculty Publications
The published pollen analysis of the Dos Cabezas giants, Geyer et al. (2003), lists variety of purported dietary pollen types. The paper also hypothesises that the giants were poisoned with plant toxins. We have severe reservations about the pollen evidence of diet and poisoning. We suggest that the analysts made several errors in their interpretation. Firstly, some of the discovered pollen types are not prehistoric endemics to the Dos Cabezas region of coastal Peru. These include the pollen of fava beans (cultivated in the Old World), and specified species of agave and sage. We believe that some or all of …
If Larvae Were Smart: A Simple Model For Optimal Settlement Behavior Of Competent Larvae, Robert J. Toonen, Andrew J. Tyre
If Larvae Were Smart: A Simple Model For Optimal Settlement Behavior Of Competent Larvae, Robert J. Toonen, Andrew J. Tyre
School of Natural Resources: Faculty Publications
Much research has been done on larval settlement cues. Rather than having simple fixed responses to constant environmental stimuli, it seems likely that settlement decisions made by individual larvae should vary depending on the individual and the conditions under which it encounters that cue. Here, we present a simple stochastic dynamic programming model that explores the conditions under which larvae may maximize their lifetime fitness by accepting lower quality habitat rather than continuing to search for superior habitat. Our model predicts that there is a relatively narrow range of parameter values over which larval selectivity among habitat types changes dramatically …
Interactions Across Spatial Scales Among Forest Dieback, Fire, And Erosion In Northern New Mexico Landscapes, Craig D. Allen
Interactions Across Spatial Scales Among Forest Dieback, Fire, And Erosion In Northern New Mexico Landscapes, Craig D. Allen
School of Natural Resources: Faculty Publications
Ecosystem patterns and disturbance processes at one spatial scale often interact with processes at another scale, and the result of such cross-scale interactions can be nonlinear dynamics with thresholds. Examples of cross-scale pattern-process relationships and interactions among forest dieback, fire, and erosion are illustrated from northern New Mexico (USA) landscapes, where long-term studies have recently documented all of these disturbance processes. For example, environmental stress, operating on individual trees, can cause tree death that is amplified by insect mortality agents to propagate to patch and then landscape or even regional-scale forest dieback. Severe drought and unusual warmth in the southwestern …
Ground Water Dependence Of Endangered Ecosystems: Nebraska’S Eastern Saline Wetlands, F. Edwin Harvey, Jerry F. Ayers, David C. Gosselin
Ground Water Dependence Of Endangered Ecosystems: Nebraska’S Eastern Saline Wetlands, F. Edwin Harvey, Jerry F. Ayers, David C. Gosselin
School of Natural Resources: Faculty Publications
Many endangered or threatened ecosystems depend on ground water for their survival. Nebraska’s saline wetlands, home to a number of endangered species, are ecosystems whose development, sustenance, and survival depend on saline ground water discharge at the surface. This study demonstrates that the saline conditions present within the eastern Nebraska saline wetlands result from the upwelling of saline ground water from within the underlying Dakota Aquifer and deeper underlying formations of Pennsylvanian age. Over thousands to tens of thousands of years, saline ground water has migrated over regional scale flowpaths from recharge zones in the west to the present-day discharge …
Soil Carbon And Tree Litter Dynamics In A Red Cedar–Scotch Pine Shelterbelt, Thomas J. Sauer, Cynthia A. Cambardella, James R. Brandle
Soil Carbon And Tree Litter Dynamics In A Red Cedar–Scotch Pine Shelterbelt, Thomas J. Sauer, Cynthia A. Cambardella, James R. Brandle
School of Natural Resources: Faculty Publications
Carbon sequestration in the woody biomass of shelterbelts has been investigated but there have been no measurements of the C stocks in soil and tree litter under this agroforestry practice. The objective of this study was to quantify C stored in surface soil layers and tree litter within and adjacent to a 35-year-old shelterbelt in eastern Nebraska, USA. The 2-row shelterbelt was composed of eastern red cedar (Juniperus virginiana) and scotch pine (Pinus sylvestris). A sampling grid was established across a section of the shelterbelt on Tomek silt loam (fine, smectitic, mesic Pachic Argiudolls). Four soil …