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Full-Text Articles in Physical Sciences and Mathematics

Photosynthetic Response Of Soybean To Twospotted Spider Mite (Acari: Tetranychydae) Injury, Adeney De Freitas Bueno, Regiane Cristina Oliveira De Freitas Bueno, Paul David Nabity, Leon George Higley, Odair Aparecido Fernandes Dec 2008

Photosynthetic Response Of Soybean To Twospotted Spider Mite (Acari: Tetranychydae) Injury, Adeney De Freitas Bueno, Regiane Cristina Oliveira De Freitas Bueno, Paul David Nabity, Leon George Higley, Odair Aparecido Fernandes

School of Natural Resources: Faculty Publications

The twospotted spider mite Tetranychus urticae Koch is a common pest on soybean plants. To clarify plantarthropod interaction on mite-soybean system, leaf fluorescence, photosynthetic responses to variable carbon dioxide levels, and chlorophyll content were evaluated. Significant photosynthetic rate reduction was observed due to stomatal limitation. Stomatal closure was the major plant physiological response. As a consequence, there was reduction in photosynthetic rates. Surprisingly, plants did not show chlorophyll content reduction associated with photosynthetic impairment. No differences in fluorescence data indicate that T. urticae injury did not impair the function of light harvesting and photoelectron transport. These results showed that T. …


Hydrochemistry Of Wetlands Along The Platte River Near Ashland, Nebraska, Carrie L. Wiese Dec 2008

Hydrochemistry Of Wetlands Along The Platte River Near Ashland, Nebraska, Carrie L. Wiese

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Comparison Of The Fuel Needed To Transport Plastic Recyclables Verses Aluminum Recyclables From Yellowstone National Park, Melissa Dejonge Dec 2008

Comparison Of The Fuel Needed To Transport Plastic Recyclables Verses Aluminum Recyclables From Yellowstone National Park, Melissa Dejonge

Department of Environmental Studies: Undergraduate Student Theses

Research has provided no definitive answers on whether PET plastic bottles or aluminum cans are a more environmentally sustainable choice as soda containers. This paper researches the fuel used in recycling each of these materials from Yellowstone National Park to processing locations. The data is used to determine which of these alternatives use less fuel in this process. It was found that plastics use more fuel when transported from Yellowstone National Park to the processing center. Aluminum uses less fuel per ton to transport from Yellowstone to the processing center. The conclusions from this research may have implications on which …


Droughtscape- Fall 2008, Kelly Smith Oct 2008

Droughtscape- Fall 2008, Kelly Smith

Droughtscape, Quarterly Newsletter of NDMC, 2007-

Washington Workshops Scheduled for November

Look for Warm West, Rainy Gulf, Easing Drought

New Drought Monitor Authors Profiled

Drought Impact Awareness Growing: Weather Forecast Offices, Geographers Highlight Issue

NDMC Takes on New Projects

Hundreds+ See NDMC at Ag Trade Show

NDMC Welcomes New Employees


Droughtscape- Fall 2008, Kelly Smith Oct 2008

Droughtscape- Fall 2008, Kelly Smith

Droughtscape, Quarterly Newsletter of NDMC, 2007-

Washington Workshops Scheduled for November

Look for Warm West, Rainy Gulf, Easing Drought

New Drought Monitor Authors Profiled

Drought Impact Awareness Growing: Weather Forecast Offices, Geographers Highlight Issue

NDMC Takes on New Projects

Hundreds+ See NDMC at Ag Trade Show

NDMC Welcomes New Employees


Variations In Stomatal Traits Of 14 Bornean Tree Species Growing On Soils With Different Moisture Contents In Lambir Hills National Park, Whitney Logan Cannon Oct 2008

Variations In Stomatal Traits Of 14 Bornean Tree Species Growing On Soils With Different Moisture Contents In Lambir Hills National Park, Whitney Logan Cannon

Department of Environmental Studies: Undergraduate Student Theses

The goal of this study was to look at variations in stomatal traits of tree species on soils with different moisture contents and fertility at Lambir Hills National Park. Stomates are important structures on the surface of leaves that mediate conduction of moisture and gassesin and out of the leaf. If stomatalt raits are important for regulation, then there should be variation in stomatal traits in regards to their soil specialization. The 14 Borneant ree speciess ampledi ncluded6 sandyl oam specialists6, clay specialistsa nd 2 generalistsfo und growing with equald istributionso n both sandyl oam and clay. Confocal microscopy was …


The Near East Drought Planning Manual: Guidelines For Drought Mitigation And Preparedness Planning, National Drought Mitigation Center Sep 2008

The Near East Drought Planning Manual: Guidelines For Drought Mitigation And Preparedness Planning, National Drought Mitigation Center

National Drought Mitigation Center: Publications

Table of Contents

1. Introduction to Drought Planning.............................................1

1.1 Effects of Drought in the Near East Region........................................................1

1.2 New Emphasis on Proactive Drought Planning .................................................. 3

1.3 Integration of Drought Planning and Sustainable Development ......................... 3

2. Explanation of Drought Concepts..............................................................5

2.1 Definitions ........................................................................................................ 5

2.2 The Nature of Drought ...................................................................................... 7

2.3 The Effects of Drought ...................................................................................... 7

3. HowtoDevelopaDroughtPlan.....................................................................................9

Step 1: Creating Political Momentum and Authority................................................9

Step 2: Coordinating Strategic Drought Planning .................................................. 12

Step 3: Fostering Involvement and Developing Common Understandings .............. 15

Step 4: Investigating Drought Monitoring, Risk, and Management Options............ 16

Step 5: Writing a …


Droughtscape- Summer 2008, Kelly Smith Jul 2008

Droughtscape- Summer 2008, Kelly Smith

Droughtscape, Quarterly Newsletter of NDMC, 2007-

VegDRI Expands West

Spring Rains Ease Drought But CA Still Dry

Scholar Donates Books

NDMC Welcomes Employees Bathke, Nothwehr

Latest Workshop Info Up

State Lawmakers to Focus on Drought Planning

Decadal Variation -- Clues to Droughts and Floods?


Impacts Of Human Physical Disturbance Of Benthic Communities In Tributaries Of The Niobrara National Scenic River, Kimberly D. Laing May 2008

Impacts Of Human Physical Disturbance Of Benthic Communities In Tributaries Of The Niobrara National Scenic River, Kimberly D. Laing

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Methods And Tools For Drought Analysis And Management, Cody L. Knutson May 2008

Methods And Tools For Drought Analysis And Management, Cody L. Knutson

School of Natural Resources: Faculty Publications

Drought is an ambiguous concept. It is often difficult to tell when you are in a drought because of its slow, protracted nature and lack of news-grabbing impacts— such as water inundating communities or buildings burning—associated with other natural disasters. It is equally difficult to track the effect of drought on people, their livelihoods, and the environment because of the ubiquitous role that water plays in our world. As a result, we often wait until we are in the midst of a water crisis to seek ad hoc solutions, which can be costly, inefficient, and highly politicized.

To overcome the …


The Fall 2008 Unl Bike Survey: Examining The Status Of Bicycle Transportation At The Univeristy Of Nebraska-Lincoln, Brent Schmoker May 2008

The Fall 2008 Unl Bike Survey: Examining The Status Of Bicycle Transportation At The Univeristy Of Nebraska-Lincoln, Brent Schmoker

Department of Environmental Studies: Undergraduate Student Theses

This study evaluates the state of bicycle use by University of Nebraska-Lincoln (UNL) students during the fall semester of 2008. An online survey was administered to a random sample of graduate and undergraduate students to determine the factors that encourage and inhibit students from using bikes for transportation to campus. The results suggest that a significant portion of the student population uses bikes for transportation to campus but several factors combine to keep the overall number of bicycle commuters low. The paper concludes with suggestions for increasing bike commuting to UNL and predictions about the future of transportation in the …


Preferences For Rural Amenities In Lancaster County, K. Koehler-Cole Apr 2008

Preferences For Rural Amenities In Lancaster County, K. Koehler-Cole

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Droughtscape- Spring 2008, Kelly Smith Apr 2008

Droughtscape- Spring 2008, Kelly Smith

Droughtscape, Quarterly Newsletter of NDMC, 2007-

San Angelo, April 24

Winter Sees Little Change in U.S. Drought

News Stories Reveal Array of Mitigation Strategies

NIDIS Wants You!

Sea Surface Temperatures Can Help Predict Drought

About DroughtScape

Recent Travels


An Affordable, Pratical Eco-House, Dave Fitzpatrick Apr 2008

An Affordable, Pratical Eco-House, Dave Fitzpatrick

Department of Environmental Studies: Undergraduate Student Theses

An eco-house or zero-energy house is not a new concept- houses with extremely low impact on their surroundings and good use of local resources have been around for centuries. This particular eco-house is designed to offer full modern services and comforts while consuming very low energy and few expensive building materials. Ideally, someone would be able to use this thesis as a blueprint for actual construction.


California Drought, An Update April 2008, Baryohay Davidoff, Fawzi Karajeh, Dean Reynolds, Eric Senter, John Woodling Apr 2008

California Drought, An Update April 2008, Baryohay Davidoff, Fawzi Karajeh, Dean Reynolds, Eric Senter, John Woodling

United States Geological Survey: Staff Publications

TABLE OF CONTENTS

CHAPTER 1. RECENT HYDROLOGIC CONDITIONS AND IMPACTS

Introduction....................................................... 1

Water Year 2007 .................................................. 1

Drought in the Colorado River Basin ..................................................... 5

Drought and Dry Conditions in the Early 2000s .................................... 7

The 2001 Klamath Basin Drought Emergency ............................... 11

CHAPTER 2. PROGRAMMATIC AND INSTITUTIONAL UPDATES

The San Francisco Bay-Sacramento/San Joaquin River Delta.................................................................. 15

The Colorado River .................................................................... 16

State Financial Assistance to Local Agencies.................................... 17

Urban Water Management Planning ................................................... 20

Water Transfers .............................................................................. 20

Small Water Systems and Drought Preparedness ................................. 21


Nebraska Cooperative Fish And Wildlife Research Unit—Usgs: Report Of Activities October 2007 – October 2008 Jan 2008

Nebraska Cooperative Fish And Wildlife Research Unit—Usgs: Report Of Activities October 2007 – October 2008

Nebraska Cooperative Fish and Wildlife Research Unit: Annual Reports

CONTENTS
INTRODUCTION . 1
PERSONNEL AND COOPERATORS . 3
Unit Personnel . 3
Coordinating Committee Members . 5
Cooperators. 6
MILESTONES . 9
AWARDS AND RECOGNITIONS . 10
THESES AND DISERTATIONS . 10
PROJECTS IN FISHERY SCIENCE . 13
Geographic Trends in Contamination of Nebraska’s Surface Waters as Indexed by Sex Steroids of Common Carp . 15
Impact of White Perch on Walleye at Branched Oak and Pawnee Reservoirs . 16
Population Assessment of Channel Catfish in Nebraska . 17
Predators of White Perch at Branched Oak and Pawnee Reservoirs . 18
Recruitment of Walleye and White Bass in Irrigation …


Trends In Twentieth-Century U.S. Snowfall Using A Quality-Controlled Dataset, Kenneth E. Kunkel, Michael Palecki, Leslie Ensor, Kenneth Hubbard, David Robinson, Kelly Redmond, David Easterling Jan 2008

Trends In Twentieth-Century U.S. Snowfall Using A Quality-Controlled Dataset, Kenneth E. Kunkel, Michael Palecki, Leslie Ensor, Kenneth Hubbard, David Robinson, Kelly Redmond, David Easterling

School of Natural Resources: Faculty Publications

A quality assessment of daily manual snowfall data has been undertaken for all U.S. long-term stations and their suitability for climate research. The assessment utilized expert judgment on the quality of each station. Through this process, the authors have identified a set of stations believed to be suitable for analysis of trends. Since the 1920s, snowfall has been declining in the West and the mid-Atlantic coast. In some places during recent years the decline has been more precipitous, strongly trending downward along the southern margins of the seasonal snow region, the southern Missouri River basin, and parts of the Northeast. …


Trends In Twentieth-Century U.S. Extreme Snowfall Seasons, Kenneth E. Kunkel, Michael A. Palecki, Leslie Ensor, David Easterling, Kenneth Hubbard, David Robinson, Kelly Redmond Jan 2008

Trends In Twentieth-Century U.S. Extreme Snowfall Seasons, Kenneth E. Kunkel, Michael A. Palecki, Leslie Ensor, David Easterling, Kenneth Hubbard, David Robinson, Kelly Redmond

School of Natural Resources: Faculty Publications

Temporal variability in the occurrence of the most extreme snowfall years, both those with abundant snowfall amounts and those lacking snowfall, was examined using a set of 440 quality-controlled, homogenous U.S. snowfall records. The frequencies with which winter-centered annual snowfall totals exceeded the 90th and 10th percentile thresholds at individual stations were calculated from 1900–01 to 2006–07 for the conterminous United States, and for 9 standard climate regions. The area-weighted conterminous U.S. results do not show a statistically significant trend in the occurrence of either high or low snowfall years for the 107-yr period, but there are regional trends. Large …


Equilibrium Sampling Used To Monitor Malodors In A Swine Waste Lagoon, Rezaul Mahmood Jan 2008

Equilibrium Sampling Used To Monitor Malodors In A Swine Waste Lagoon, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.


Eco-Geomorphic Implications Of Hillslope Aspect: Inferences From Analysis Of Landscape Morphology In Central New Mexico, Erkan Istanbulluoglu, Omer Yetemen, Enrique R. Vivoni, Hugo A. Gutierrez-Jurado, Rafael L. Bras Jan 2008

Eco-Geomorphic Implications Of Hillslope Aspect: Inferences From Analysis Of Landscape Morphology In Central New Mexico, Erkan Istanbulluoglu, Omer Yetemen, Enrique R. Vivoni, Hugo A. Gutierrez-Jurado, Rafael L. Bras

School of Natural Resources: Faculty Publications

We investigate the influence of hillslope aspect on landscape morphology in central New Mexico, where differences in soils, vegetation, and landforms are observed between mesic north-facing and xeric south-facing slopes. Slope–area and curvature–area relations, derived from a Digital Elevation Model (DEM), are used to characterize the opposing hillslope morphologies. In all geologies and elevation ranges studied, topographic data reveal significantly steeper slopes in north-facing aspects, and shallower slopes in south-facing aspects. North-facing slope curvatures are also greater than south-facing curvatures. Using a conceptual slope-area model, we suggest that for a given drainage area, steeper north-facing slopes imply lower soil erodibility. …


Buffered, Lagged, Or Cooled? Disentangling Hyporheic Influences On Temperature Cycles In Stream Channels, Alicia S. Arrigoni, Geoffrey C. Poole, Leal A. K. Mertes, Scott J. O'Daniel, William W. Woessner, Steven A. Thomas Jan 2008

Buffered, Lagged, Or Cooled? Disentangling Hyporheic Influences On Temperature Cycles In Stream Channels, Alicia S. Arrigoni, Geoffrey C. Poole, Leal A. K. Mertes, Scott J. O'Daniel, William W. Woessner, Steven A. Thomas

School of Natural Resources: Faculty Publications

We monitored summertime base flow water temperatures of hyporheic discharge to surface water in main, side, and spring channels located within the bank-full scour zone of the gravel- and cobble-bedded Umatilla River, Oregon, USA. Diel temperature cycles in hyporheic discharge were common, but spatially variable. Relative to the main channel’s diel cycle, hyporheic discharge locations typically had similar daily mean temperatures, but smaller diel ranges (compressed by 2 to 6°C) and desynchronized phases (offset by 0 to 6 h). In spring channels (which received only hyporheic discharge), surface water diel cycles were also compressed (by 2 to 6°C) and desynchronized …


Application Of A Routing Model For Detecting Channel Flow Changes With Minimal Data, Jozsef Szilagyi, Nicholas Pinter, Rob Venczel Jan 2008

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 Jan 2008

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 Jan 2008

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 Jan 2008

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.


New Findings About The Complementary Relationship-Based Evaporation Estimation Methods, Jozsef Szilagyi, Janos Jozsa Jan 2008

New Findings About The Complementary Relationship-Based Evaporation Estimation Methods, Jozsef Szilagyi, Janos Jozsa

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 Jan 2008

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.


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 Jan 2008

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 Jan 2008

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 …


Droughtscape- Winter 2008, Kelly Smith Jan 2008

Droughtscape- Winter 2008, Kelly Smith

Droughtscape, Quarterly Newsletter of NDMC, 2007-

Now Up & On-Line:

Winter 2008 Outlook and Oct.-Dec. ’07 Summary

NDMC Experts Serve as Resource for Media

Drought Hits Ag and Urban Interests in 2007

Climatological Summary of Drought in 2007

NDMC Welcomes Data Miner Bo Zhang

New Grant Awards