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School of Natural Resources: Faculty Publications

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Articles 1141 - 1170 of 1586

Full-Text Articles in Physical Sciences and Mathematics

Departures From Gibrat’S Law, Discontinuities And City Size Distributions, Ahjond S. Garmestani, Craig R. Allen, Colin M. Gallagher, John Mittelstaedt Sep 2007

Departures From Gibrat’S Law, Discontinuities And City Size Distributions, Ahjond S. Garmestani, Craig R. Allen, Colin M. Gallagher, John Mittelstaedt

School of Natural Resources: Faculty Publications

Cities are complex, self-organizing, evolving systems and the emergent patterns they manifest provide insight into the dynamic processes in urban systems. This article analyses city size distributions, by decade, from the south-eastern region of the US for the years 1860–1990. It determines if the distributions are clustered into size classes and documents changes in the pattern of size classes over time. A statistical hypothesis test was also performed to detect dependence between city size and growth using discrete probability calculations under the assumption of Gibrat’s law. The city size distributions for the south-eastern region of the US were discontinuous, with …

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Parasite Findings In Archeological Remains: Diagnosis And Interpretation, Adauto Arajuo, Karl J. Reinhard, Luiz Fernando Ferreira Aug 2007

Parasite Findings In Archeological Remains: Diagnosis And Interpretation, Adauto Arajuo, Karl J. Reinhard, Luiz Fernando Ferreira

School of Natural Resources: Faculty Publications

Paleoparasitology has contributed to resolving the debate about the peopling of the Americas and determining the antiquity of human parasite infection. Hookworm (Ancylostomidae) and whipworm (Trichuris trichiura) and other exclusive human intestinal parasites have been recorded in pre-Columbian America. These parasite species originated in pre-hominids and have accompanied humans across continents when people went out of Africa. However, for those human populations that crossed the Bering Land Bridge from Siberia to Alaska, cold climate conditions hampered parasite transmission. Alternative migration routes have been proposed to explain the presence of these parasites in pre-Columbian populations in the Americas. Other …

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Increase In Near-Surface Atmospheric Moisture Content Due To Land Use Changes: Evidence From The Observed Dewpoint Temperature Data, Rezaul Mamood, Kenneth G. Hubbard, Ronnie D. Leeper, Stuart A. Foster Aug 2007

Increase In Near-Surface Atmospheric Moisture Content Due To Land Use Changes: Evidence From The Observed Dewpoint Temperature Data, Rezaul Mamood, Kenneth G. Hubbard, Ronnie D. Leeper, Stuart A. Foster

School of Natural Resources: Faculty Publications

Land use change can significantly affect root zone soil moisture, surface energy balance, and near-surface atmospheric temperature and moisture content. During the second half of the twentieth century, portions of the North American Great Plains have experienced extensive introduction of irrigated agriculture. It is expected that land use change from natural grass to irrigated land use would significantly increase nearsurface atmospheric moisture content. Modeling studies have already shown an enhanced rate of evapotranspiration from the irrigated areas. The present study analyzes observed dewpoint temperature (Td) to assess the affect of irrigated land use on near-surface atmospheric moisture content. This investigation …

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Hunter-Gatherer Use Of Small Animal Food Resources: Coprolite Evidence, Karl J. Reinhard, J. R. Ambler, C. R. Szuter Jul 2007

Hunter-Gatherer Use Of Small Animal Food Resources: Coprolite Evidence, Karl J. Reinhard, J. R. Ambler, C. R. Szuter

School of Natural Resources: Faculty Publications

Faunal remains are commonly found in coprolites and provide direct evidence of animal consumption. An evaluation of hunter-gatherer coprolites from the Southwest United States shows that animal bone in coprolites can be used to assess patterns of hunting, food preparation, and general importance of small animals in diet. This is demonstrated by a comparison of faunal assemblages between two hunter-gatherer sites with respect to small animal hunting strategies. The sites are Dust Devil Cave on the Colorado Plateau, an Archaic winter habitation, and Hinds Cave, a warm season Archaic habitation in the lower Pecos of Texas. The results indicate that …

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Patterns Of Fish Diversity In A Mainstem Missouri River Reservoir And Associated Delta In South Dakota And Nebraska, Usa, Mark A. Kaemingk, Brian D.S. Graeb, Christopher W. Hoagstrom, David W. Willis Jun 2007

Patterns Of Fish Diversity In A Mainstem Missouri River Reservoir And Associated Delta In South Dakota And Nebraska, Usa, Mark A. Kaemingk, Brian D.S. Graeb, Christopher W. Hoagstrom, David W. Willis

School of Natural Resources: Faculty Publications

There is an expansive and expanding delta at the confluence of the Niobrara and Missouri Rivers in the Lewis and Clark Reservoir. The delta provides diverse aquatic habitat that is somewhat similar to the historic Missouri River and to remnant river habitats. As such, the delta may have relatively high fish species diversity compared to lentic reservoir habitats. To compare patterns of fish diversity between the delta and reservoir habitats, we collected fish in several nursery habitats in both areas using four gear types (seine, gill net, electrofisher and fyke net) on three occasions (July, August and September) in 2005. …

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Linking Flux Network Measurements To Continental Scale Simulations: Ecosystem Carbon Dioxide Exchange Capacity Under Non-Water-Stressed Conditions, Katherine B. Owen, John Tenhunen, Markus Reichstein, Quan Wang, Eva Falge, Ralf Geyer, Xiangming Xiaos, Paul Stoy, Christof Ammann, Altaf Arain, Marc Aubinet, Mika Aurela, Christian Bernhofer, Bogdan Chojnicki, Andre Granier, Thomas Gruenwald, Julian Hadley, Bernard Heinesch, David Hollinger, Alexander Knohl, Werner Kutsch, Annalea Lohila, Tilden Meyers, Eddy Moors, Christine Moureaux, Kim Pilegaard, Nobuko Saigusa, Shashi Verma, Timo Vesala, Chris Vogel Apr 2007

Linking Flux Network Measurements To Continental Scale Simulations: Ecosystem Carbon Dioxide Exchange Capacity Under Non-Water-Stressed Conditions, Katherine B. Owen, John Tenhunen, Markus Reichstein, Quan Wang, Eva Falge, Ralf Geyer, Xiangming Xiaos, Paul Stoy, Christof Ammann, Altaf Arain, Marc Aubinet, Mika Aurela, Christian Bernhofer, Bogdan Chojnicki, Andre Granier, Thomas Gruenwald, Julian Hadley, Bernard Heinesch, David Hollinger, Alexander Knohl, Werner Kutsch, Annalea Lohila, Tilden Meyers, Eddy Moors, Christine Moureaux, Kim Pilegaard, Nobuko Saigusa, Shashi Verma, Timo Vesala, Chris Vogel

School of Natural Resources: Faculty Publications

This paper examines long-term eddy covariance data from 18 European and 17 North American and Asian forest, wetland, tundra, grassland, and cropland sites under nonwater- stressed conditions with an empirical rectangular hyperbolic light response model and a single layer two light-class carboxylase-based model. Relationships according to ecosystem functional type are demonstrated between empirical and physiological parameters, suggesting linkages between easily estimated parameters and those with greater potential for process interpretation. Relatively sparse documentation of leaf area index dynamics at flux tower sites is found to be a major difficulty in model inversion and flux interpretation. Therefore, a simplification of the …

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Dental Wash: A Problematic Method For Extracting Microfossils From Teeth (Galley Proofs), Célia H. C. Boyadjian, Sabine Eggers, Karl J. Reinhard Feb 2007

Dental Wash: A Problematic Method For Extracting Microfossils From Teeth (Galley Proofs), Célia H. C. Boyadjian, Sabine Eggers, Karl J. Reinhard

School of Natural Resources: Faculty Publications

A variety of microfossils, originating from plant foods, become trapped in the dental calculus matrix. Processing of dental calculus allows extraction of these microfossils. The resulting data can be used to reconstruct diet at the individual and population levels as the identification of microfossils like starch grains and phytoliths to the generic level, and sometimes to the species level, is possible. However, in some archaeological sites, dental calculus deposits do not preserve well enough to be processed. To prevent the loss of information in such cases, we present a technique, called ‘‘dental wash’’. It permits extracting microfossils from cryptic dental …

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Comment On Reinterpreting The Pollen Data From Dos Cabezas, Karl J. Reinhard, Vaughn M. Bryant, Sheila Dorsey Vinton Feb 2007

Comment On Reinterpreting The Pollen Data From Dos Cabezas, Karl J. Reinhard, Vaughn M. Bryant, Sheila Dorsey Vinton

School of Natural Resources: Faculty Publications

The published pollen analysis of the Dos Cabezas giants, Geyer et al. ([2003]), lists a variety of purported dietary pollen types. The paper also hypothesizes 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 …

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Documentation Of Uncertainties And Biases Associated With Surface Temperature Measurement Sites For Climate Change Assessment, Roger A. Pielke Sr., John Nielsen-Gammon, Christopher Davey, Jim Angel, Odie Bliss, Nolan Doesken, Ming Cal, Souleymane Fall, Dev Niyogi, Kevin Gallo, Robert Hale, Kenneth Hubbard, Xiaomao Lin, Hong Li, Sethu Raman Jan 2007

Documentation Of Uncertainties And Biases Associated With Surface Temperature Measurement Sites For Climate Change Assessment, Roger A. Pielke Sr., John Nielsen-Gammon, Christopher Davey, Jim Angel, Odie Bliss, Nolan Doesken, Ming Cal, Souleymane Fall, Dev Niyogi, Kevin Gallo, Robert Hale, Kenneth Hubbard, Xiaomao Lin, Hong Li, Sethu Raman

School of Natural Resources: Faculty Publications

Davey and Pielke (2005) presented photographic documentation of poor observation sites within the U.S. Historical Climate Reference Network (USHCN) with respect to monitoring long-term surface air temperature trends. [These photographs were first shown to the community at the 2002 Asheville, North Carolina, meeting of the American Association of State Climatologists (see information online at www. stateclimate.org/meetings/minutes/2002minutes).] Peterson (2006) compared the adjusted climate records of many of these stations and concluded that the similarity between the homogeneity adjusted time series from the good and poorly sited stations supports the view that even stations that do not, upon visual inspection, appear to …

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Development Of The Soil Moisture Index To Quantify Agricultural Drought And Its “User Friendliness” In Severity-Area-Duration Assessment, Venkataramana Sridhar, Kenneth Hubbard, Jinshing You, Eric D. Hunt Jan 2007

Development Of The Soil Moisture Index To Quantify Agricultural Drought And Its “User Friendliness” In Severity-Area-Duration Assessment, Venkataramana Sridhar, Kenneth Hubbard, Jinshing You, Eric D. Hunt

School of Natural Resources: Faculty Publications

This paper examines the role of soil moisture in quantifying drought through the development of a drought index using observed and modeled soil moisture. In Nebraska, rainfall is received primarily during the crop-growing season and the supply of moisture from the Gulf of Mexico determines if the impending crop year is either normal or anomalous and any deficit of rain leads to a lack of soil moisture storage. Using observed soil moisture from the Automated Weather Data Network (AWDN), the actual available water content for plants is calculated as the difference between observed or modeled soil moisture and wilting point, …

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Impacts Of Predators On Northern Bobwhites In The Southeast, John P. Carroll, Susan N. Ellis-Felege, William E. Palmer Jan 2007

Impacts Of Predators On Northern Bobwhites In The Southeast, John P. Carroll, Susan N. Ellis-Felege, William E. Palmer

School of Natural Resources: Faculty Publications

The northern bobwhite quail (Colinus virginianus) is an important game bird that is intensively managed for hunting recreation in the southeastern United States. Despite interest regionwide, populations have been declining for much of the last 40 years (Brennan 1999). Population declines in the Southeast have occurred as a result of widespread habitat loss associated with land-use changes (Brennan 1999). These land-use changes include both conversion from agricultural to forest landscapes and changes in forest management practices, which result in dense forest canopies that shade required ground vegetation (Brennan 1999, Rollins and Carroll 2001). In addition, low-quality habitats may …

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Vegetative And Invertebrate Community Characteristics Of Conservation Reserve Program Fields Relative To Gamebirds In Western Kansas, Elizabeth D. Doxon, John P. Carroll Jan 2007

Vegetative And Invertebrate Community Characteristics Of Conservation Reserve Program Fields Relative To Gamebirds In Western Kansas, Elizabeth D. Doxon, John P. Carroll

School of Natural Resources: Faculty Publications

We examined vegetation and invertebrate characteristics, including insect biomass, insect-prey, six Families and seven Orders in four varieties of Conservation Reserve Program (CP10, improved CP10, CP2 and CP25) and wheat fields in western Kansas during Jun. and Jul., 2004 and 2005 relative to gamebird chick ecology. CP10 fields had less bare ground and forbs compared to the other Conservation Practices and CP25 fields had lost much of their original forb component by the end of the study. Although there was little forb component, CP10 fields had high invertebrate biomass. However, CP10 fields demonstrated sizeable declines in the estimated effect size …

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Nutrient Cycling In Forage Production Systems, David A. Wedin, Michael P. Russelle Jan 2007

Nutrient Cycling In Forage Production Systems, David A. Wedin, Michael P. Russelle

School of Natural Resources: Faculty Publications

In most forage production systems, the nutrients needed for plant growth are provided by microbially mediated breakdown and release of plant-available mineral nutrients from dead plant tissues, livestock excreta, soil organic matter, and geochemically bound mineral forms. Even in fertilized forage systems, determining appropriate fertilizer application rates requires a "systems" approach on the part of the manager (e.g., Di and Cameron, 2000; Rotz et al., 2002). Fertilizer additions are simply one input in the system of inputs, outputs, pools, and fluxes that characterize nutrient cycling in a particular ecosystem.

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Analysis Of The Nonlinearity In The Runoff Response To Precipitation Through Numerical Modeling, Jozsef Szilagyi Jan 2007

Analysis Of The Nonlinearity In The Runoff Response To Precipitation Through Numerical Modeling, Jozsef Szilagyi

School of Natural Resources: Faculty Publications

No abstract provided.

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On Diurnal Riparian Zone Groundwater-Level And Streamflow Fluctuations, Jozsef Szilagyi, Zoltan Gribovszki, Peter Kalicz, Mihaly Kucsara Jan 2007

On Diurnal Riparian Zone Groundwater-Level And Streamflow Fluctuations, Jozsef Szilagyi, Zoltan Gribovszki, Peter Kalicz, Mihaly Kucsara

School of Natural Resources: Faculty Publications

No abstract provided.

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On The Inherent Asymmetric Nature Of The Complementary Relationship Of Evaporation, Jozsef Szilagyi Jan 2007

On The Inherent Asymmetric Nature Of The Complementary Relationship Of Evaporation, Jozsef Szilagyi

School of Natural Resources: Faculty Publications

No abstract provided.

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Estimation Of Catchment-Scale Evapotranspiration From Baseflow Recession Data: Numerical Model And Practical Application Results, Jozsef Szilagyi, Zoltan Gribovszki, Peter Kalicz Jan 2007

Estimation Of Catchment-Scale Evapotranspiration From Baseflow Recession Data: Numerical Model And Practical Application Results, Jozsef Szilagyi, Zoltan Gribovszki, Peter Kalicz

School of Natural Resources: Faculty Publications

No abstract provided.

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Hungarian National Report On Iahs: 2003-2006, Jozsef Szilagyi Jan 2007

Hungarian National Report On Iahs: 2003-2006, Jozsef Szilagyi

School of Natural Resources: Faculty Publications

No abstract provided.

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On The Inherent Asymmetric Nature Of The Complementary Relationship Of Evaporation, Jozsef Szilagyi Jan 2007

On The Inherent Asymmetric Nature Of The Complementary Relationship Of Evaporation, Jozsef Szilagyi

School of Natural Resources: Faculty Publications

No abstract provided.

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An Evaluation Of Modis 250-M Data For Green Lai Estimation In Crops, Anatoly A. Gitelson, Brian D. Wardlow, Galina P. Keydan, Bryan Leavitt Jan 2007

An Evaluation Of Modis 250-M Data For Green Lai Estimation In Crops, Anatoly A. Gitelson, Brian D. Wardlow, Galina P. Keydan, Bryan Leavitt

School of Natural Resources: Faculty Publications

Green leaf area index (LAI) is an important variable for climate modeling, estimates of primary production, agricultural yield forecasting, and many other diverse applications. Remotely sensed data provide considerable potential for estimating LAI at local, regional, and global scales. The goal of this study was to retrieve green LAI from MODIS 250-m vegetation index (VI) data for irrigated and rainfed maize and soybeans. The performance of both MODIS-derived NDVI and Wide Dynamic Range Vegetation Index (WDRVI) were evaluated across three growing seasons (2002 through 2004) over a wide range of LAI and also compared to the performance of NDVI and …

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Bird Movement Predicts Buggy Creek Virus Infection In Insect Vectors, Charles R. Brown, Mary Bomberger Brown, Amy T. Moore, Nicholas Komar Jan 2007

Bird Movement Predicts Buggy Creek Virus Infection In Insect Vectors, Charles R. Brown, Mary Bomberger Brown, Amy T. Moore, Nicholas Komar

School of Natural Resources: Faculty Publications

Predicting the spatial foci of zoonotic diseases is a major challenge for epidemiologists and disease ecologists. Migratory birds are often thought to be responsible for introducing some aviozoonotic pathogens such as West Nile and avian influenza viruses to a local area, but most information on how bird movement correlates with virus prevalence is anecdotal or indirect. We report that the prevalence of Buggy Creek virus (BCRV) infection in cimicid swallow bugs (Oeciacus vicarius), the principal invertebrate vector for this virus, was directly associated with the likelihood of movement by cliff swallows (Petrochelidon pyrrhonota), an amplifying host …

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Ecological Correlates Of Buggy Creek Virus Infection In Oeciacus Vicarius, Southwestern Nebraska, 2004, Amy T. Moore, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown Jan 2007

Ecological Correlates Of Buggy Creek Virus Infection In Oeciacus Vicarius, Southwestern Nebraska, 2004, Amy T. Moore, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown

School of Natural Resources: Faculty Publications

Buggy Creek virus (family Togaviridae, genus Alphavirus, BCRV) is an alphavirus within the western equine encephalitis virus complex whose primary vector is the swallow bug, Oeciacus vicarius Horvath (Hemiptera: Cimicidae), an ectoparasite of the colonially nesting cliff swallow, Petrochelidon pyrrhonota, that is also a frequent host for the virus.We investigated ecological correlates of BCRV infection in 100-bug pools at 14 different swallow colony sites in southwestern Nebraska from summer 2004, by using plaque assay on Vero cells to identify cytopathic virus and reverse transcription-polymerase chain reaction to identify noncytopathic viral RNA. We found 26.7% of swallow bug pools …

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Impacts Of The Agricultural Green Revolution Induced Land Use Changes On Air Temperatures In India, Rezaul Mahmood Jan 2007

Impacts Of The Agricultural Green Revolution Induced Land Use Changes On Air Temperatures In India, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.

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Relationship Between Soil Moisture Of Near Surface And Multiple Depths Of The Root Zone Under Heterogeneous Land Uses And Varying Hydroclimatic Conditions, Rezaul Mahmood Jan 2007

Relationship Between Soil Moisture Of Near Surface And Multiple Depths Of The Root Zone Under Heterogeneous Land Uses And Varying Hydroclimatic Conditions, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.

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Nebraska Cooperative Fish And Wildlife Research Unit: Report Of Activities October 2006 – October 2007, Craig R. Allen, Kevin L. Pope Jan 2007

Nebraska Cooperative Fish And Wildlife Research Unit: Report Of Activities October 2006 – October 2007, Craig R. Allen, Kevin L. Pope

School of Natural Resources: Faculty Publications

INTRODUCTION 1
PERSONNEL AND COOPERATORS 3
Unit Personnel 3
Coordinating Committee Members 5
Cooperators 6
MILESTONES 9
PROJECTS IN FISHERY SCIENCE 11
Impact of White Perch on Walleye at Branched Oak and Pawnee Reservoirs 13
Predators of White Perch at Branched Oak and Pawnee Reservoirs 14
Recruitment of Walleye and White Bass in Irrigation Reservoirs 15
PROJECTS IN WILDLIFE SCIENCE 17
Amphibian Monitoring Techniques (in Relation to Wetland Qualities and the Surrounding Landscape
– Rainwater Basin Region) 19
Assessing Local and Regional Variability in Productivity and Fidelity of Grassland Birds on National
Park Service Units in the Great Plains 20 …

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Assistance With Wildlife Damage Problems In Nebraska, Scott E. Hygnstrom, John M. Hobbs, James G. Bruner, James Weverka, Dallas R. Virchow, Dennis M. Ferraro Oct 2006

Assistance With Wildlife Damage Problems In Nebraska, Scott E. Hygnstrom, John M. Hobbs, James G. Bruner, James Weverka, Dallas R. Virchow, Dennis M. Ferraro

School of Natural Resources: Faculty Publications

Nebraskans who experience damage and nuisance problems with wildlife can get assistance from several public and private organizations. This NebFact describes the most direct route to the solution of your problem. A reference guide (Table I) lists who to contact for information, materials, permits, and hands-on assistance. Wildlife play an important role in our environment. In addition, we gain many recreational, economic, and aesthetic benefits from them. Unfortunately, the activities of wildlife occasionally conflict with human interests in personal property, agricultural production, and health and safety. The most common wildlife damage and nuisance problems in Nebraska are caused by bats, …

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Planning For Robust Reserve Networks Using Uncertainty Analysis, Atte Moilanen, Michael C. Runge, Jane Elith, Andrew Tyre, Yohay Carmel, Eric Fegraus, Brendan A. Wintle, Mark Burgman, Yakov Ben-Haim Sep 2006

Planning For Robust Reserve Networks Using Uncertainty Analysis, Atte Moilanen, Michael C. Runge, Jane Elith, Andrew Tyre, Yohay Carmel, Eric Fegraus, Brendan A. Wintle, Mark Burgman, Yakov Ben-Haim

School of Natural Resources: Faculty Publications

Planning land-use for biodiversity conservation frequently involves computer-assisted reserve selection algorithms. Typically such algorithms operate on matrices of species presence–absence in sites, or on species-specific distributions ofmodel predicted probabilities of occurrence in grid cells. There are practically always errors in input data—erroneous species presence–absence data, structural and parametric uncertainty in predictive habitat models, and lack of correspondence between temporal presence and long-run persistence. Despite these uncertainties, typical reserve selection methods proceed as if there is no uncertainty in the data or models. Having two conservation options of apparently equal biological value, one would prefer the option whose value is relatively …

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Price Elasticity Reconsidered: Panel Estimation Of An Agricultural Water Demand Function, Karina Schoengold, David L. Sunding, Georgina Moreno Sep 2006

Price Elasticity Reconsidered: Panel Estimation Of An Agricultural Water Demand Function, Karina Schoengold, David L. Sunding, Georgina Moreno

School of Natural Resources: Faculty Publications

Using panel data from a period of water rate reform, this paper estimates the price elasticity of irrigation water demand. Price elasticity is decomposed into the direct effect of water management and the indirect effect of water price on choice of output and irrigation technology. The model is estimated using an instrumental variables strategy to account for the endogeneity of technology and output choices in the water demand equation. Estimation results indicate that the price elasticity of agricultural water demand is -0.79, which is greater than that found in previous studies.

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Ecophysiology Of Two Native Invasive Woody Species And Two Dominant Warm-Season Grasses In The Semiarid Grasslands Of The Nebraska Sandhills, Kathleen D. Eggemeyer, Tala Awada, David A. Wedin, F. Edwin Harvey, Xinhua Zhou Sep 2006

Ecophysiology Of Two Native Invasive Woody Species And Two Dominant Warm-Season Grasses In The Semiarid Grasslands Of The Nebraska Sandhills, Kathleen D. Eggemeyer, Tala Awada, David A. Wedin, F. Edwin Harvey, Xinhua Zhou

School of Natural Resources: Faculty Publications

Populations of Pinus ponderosa and Juniperus virginiana are expanding into semiarid Sandhills grasslands in Nebraska. To evaluate the physiological basis of their success, we measured the seasonal course of leaf gas exchange, plant water status, and carbon isotope discrimination in these two native trees and two native C4 grasses (Schizachyrium scoparium and Panicum virgatum). Compared to the trees, grasses had higher net photosynthetic rates (Anet) and water use efficiency (WUE) and more negative predawn and midday water potentials (Ψ) in June and July. While leaf Ψ and rates of leaf gas exchange declined for all …

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Climate Variability Has A Stabilizing Effect On The Coexistence Of Prairie Grasses, Peter B. Adler, Janneke Hille Ris Lambers, Phaedon C. Kyriakidis, Qingfeng Guan, Jonathan M. Levine Aug 2006

Climate Variability Has A Stabilizing Effect On The Coexistence Of Prairie Grasses, Peter B. Adler, Janneke Hille Ris Lambers, Phaedon C. Kyriakidis, Qingfeng Guan, Jonathan M. Levine

School of Natural Resources: Faculty Publications

How expected increases in climate variability will affect species diversity depends on the role of such variability in regulating the coexistence of competing species. Despite theory linking temporal environmental fluctuations with the maintenance of diversity, the importance of climate variability for stabilizing coexistence remains unknown because of a lack of appropriate long-term observations. Here, we analyze three decades of demographic data from a Kansas prairie to demonstrate that interannual climate variability promotes the coexistence of three common grass species. Specifically, we show that (i) the dynamics of the three species satisfy all requirements of ‘‘storage effect’’ theory based on recruitment …

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