Natural Resources and Conservation Commons^™

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

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

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, …

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

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

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

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.

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 …

From Debate To Design: Issues In Clean Energy And Climate Change Law And Policy, Leslie Parker, Jennifer Ronk, Rachel Maxwell, Bradford Gentry, Marijn Wilder, James Cameron

Yale School of the Environment Publications Series

A report on the work of the REIL Network 2007-2008

Residential Building Energy Consumption And Loss Reduction Methods, Edward J. Balthazar

Theses, Dissertations and Capstones

Home energy costs can be a large monthly expense for many people. Reduction of home energy consumption has multiple benefits – personal cost reduction, increased comfort, and global stewardship. The author embarked on a multi-year series of projects to reduce energy losses. The projects include plugging air infiltration gaps, installing further insulation layers, and buying an energy efficient heat pump. Data for natural gas and electricity use and local weather are presented, with heating as the major energy use. A linear correlation between cold weather conditions and natural gas consumption, and a cyclical annual weather-energy algorithm were both developed. Conductive …

Mammals Of Nebraska: Checklist, Key, And Bibliography, Hugh H. Genoways, Justin D. Hoffman, Patricia Freeman, Kenneth N. Geluso, Russell A. Benedict, Jeffrey J Huebschman

University of Nebraska State Museum: Staff and Affiliates, Publications

The Recent mammalian fauna of Nebraska is composed of 89 native species, 8 domestic species that can have feral populations, and 4 wild species introduced by humans, but not by intentional action. Thus, the included checklist and dichotomous key contain 101 species of mammals. Of the native species, 36 are rodents, 20 carnivores, 13 bats, 7 shrews and mole, 7 even-toed ungulates, 4 rabbits and hares, 1 armadillo, and 1 opossum. Another 8 species are identified as potentially occurring in peripheral areas of Nebraska. The bibliography includes 1693 entries that each contain data concerning one or more species of mammals …

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

School of Natural Resources: Faculty Publications

No abstract provided.

Visualization Of Groundwater Flow Within Touching-Vu And Matrix Porosity In An Eogenetic Karst Aquifer, Lee J. Florea, Kevin J. Cunningham, Stephen Altobelli

Earth, Environmental, and Atmospheric Sciences Faculty Publications

In this study, we use an innovative, non-invasive technology, nuclear magnetic resonance imaging (NMRI), to visualize the direction and magnitude of groundwater flow in field samples of late Pleistocene limestone of the Biscayne aquifer. Specific goals of the first set of NMRI experiments are to map the advective velocity of water flowing at two rates of specific discharge (0.00025 and 0.00013 m/s) through a 10-cm-diameter cylindrical, epoxy-resin model. The model interior accurately reproduces a well-connected maze of ichnologically influenced, centimeter-scale, touching-vug macroporosity common within preferred flow zones in parts of the Biscayne aquifer. A second set of NMRI experiments investigates …

Fisheries Research Report No.172 - Identifying Obstacles To Profitably Growing Out Western Rock Lobsters, Roy Melville-Smith, Danielle Johnston, B. Johnston, N. J. Thomson

Fisheries Research Reports

A Report Prepared for the Aquaculture Development Council.

The cost of growing out western rock lobsters from pueruli to marketable-sized lobsters has been modeled from available information. The model uses different scenarios of survival rates, marketing weights, market prices, feed costs, puerulus prices, labour costs, puerulus compensation costs, discount rates and capital costs. The sensitivity of estimated profitability to various input costs and rock lobster prices was assessed by estimating the impact of changes on the estimates of net present value (NPV) internal rate of return (IRR) and benefit:cost ratio. Importantly, the aim of the study was to identify key …

Focus Group On Karst Hydrology - Conceptual Models, Aquifer Characterization, And Numerical Modeling, Martin Sauter, Lee J. Florea, Others

Earth, Environmental, and Atmospheric Sciences Faculty Publications

No abstract provided.

Ua12/13 Wku Sustainability Report 2007-2008, Christian Ryan-Downing

Sustainability Publications and Resources

No abstract provided.

Effects Of Habitat Disturbance On Survival Rates Of Softshell Turtles (Apalone Spinifera) In An Urban Stream, Michael Plummer, David G. Krementz, Larkin A. Powell, Nathan Mills

School of Natural Resources: Faculty Publications

We monitored Spiny Softshell Turtles (Apalone spinifera) using mark-recapture during 1994– 2005 in Gin Creek, Searcy, Arkansas. In 1997–2000 the creek bed and riparian zone were bulldozed in an effort to remove debris and improve water flow. This disturbance appeared to reduce the quantity and quality of turtle habitat. We tested for the potential effect of this habitat disturbance on the survival rates of marked turtles. We estimated annual survival rates for the population using models that allowed for variation in survival by state of maturation, year, and effects of the disturbance; we evaluated two different models of …

Technology-Aided Participative Methods In Environmental Assessment: An International Perspective, Ainhoa Gonzalez, Alan Gilmer, Ronan Foley, John Sweeney, John Fry

Articles

Provisions for citizen involvement in the assessment of potential environmental effects of certain plans, programmes and projects are present in current legislation. An international survey revealed that public participation is common practice in European and some other countries worldwide. However, a number of issues are observed to affect public involvement in EIA/SEA processes and expert opinion differs when evaluating the effectiveness of existing participative methods. Results suggest that technology-aided methods can improve traditional participation processes. In particular, GIS has the potential to increase community knowledge and enhance involvement by communicating information more effectively. Variable accessibility to technology and data quality …

Paleoecology Of Early Jurassic Navajo Sandstone Interdune Deposits, Nathan Daniel Wilkens

Canyonlands Research Bibliography

The Lower Jurassic Navajo Sandstone represents a desert that covered more than 366,000 square kilometers. Localized interdune deposits commonly occur along the eastern edge of this desert that include carbonates, bioturbated layers, and plant fossils. Previous studies of these deposits focused on specific fossil types or isolated sites. This study involved a comprehensive analysis of the paleoecology of interdune deposits with an integrated approach combining paleontology, sedimentology and geochemistry. The methods used in this study were devised to test specific paleoecological and preservational questions, including water sources and geochemistry, sedimentation mechanisms, fossil identification and paleoecology, taphonomy, and diagenesis. Three hypotheses …

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

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. …

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 …

A Synthesis Of Live Fuel Moisture And Wildland Fire And Development Of A National Historical Live Fuel Moisture Database, William M. Jolly Dr.

Joint Fire Science Program Research Project Reports

Live fuels are a key component to the wildland fuel complex but little is know about their contribution to fire danger or fire behavior. This review attempts to quantify our current understanding of the role that live fuels play in combustion and how those characteristics are quantified into prediction systems that fire managers use to assess fire danger or fire behavior as well as how live fuel parameters for those systems are measured. We review how live fuels are incorporated into three fire danger and fire behavior prediction systems that have found widespread use throughout the world. We discuss the …

Behaveplus And Flammap Technology Transfer, Patricia Andrews, Mark Finney

Joint Fire Science Program Research Project Reports

This project was conducted in response to the need identified under Task 1 (RFP 2005-4)—extension of technology transfer activities beyond the conclusion of successfully completed JFSP funded projects or other applicable wildland fire research. Development of the BehavePlus fire modeling system and the FlamMap fire behavior analysis and mapping system and supporting technology transfer material was funded in part under JFSP project #98-1-8-02. After successful completion of that project, development of those systems and supporting material continued under other funding. FlamMap was used in JFSP project #01-1-3-21 “Cumulative effects of fuel management on landscape-scale fire behavior and effects.” A significant …

Bringing The Fire Effects Information System Up-To-Date And Improving Service To Land Managers, Jane Kapler Smith, Fire Modeling Institute Information Team

Joint Fire Science Program Research Project Reports

This project delivers up-to-date, science-based information about species nominated by wildland managers for revision in or addition to the Fire Effects Information System (FEIS). FEIS now provides 1,081 literature reviews covering 1,139 taxa. This JFSP task has supported the rewriting of 9% of FEIS reviews, addition of reviews that increase FEIS content by 9%, and small updates to 25% of the database. Each FEIS species review addresses the basic biology of the species, fire regimes, fire's role in the life history and persistence of the species, competition and successional patterns, and issues regarding fuel management, prescribed fire, and postfire rehabilitation. …

Burn Severity Mapping Using Simulation Modeling And Satellite Imagery, Robert E. Keane, Eva C. Karau, Elizabeth Reinhardt

Joint Fire Science Program Research Project Reports

As wildfires becomes an increasingly important issue affecting our nation’s landscapes, fire managers must quickly assess possible adverse fire effects to efficiently allocate resources for rehabilitation or remediation. While burn severity maps derived from satellite imagery can provide a landscape view of relative fire impacts, fire effects simulation models can also provide spatial fire severity estimates along with the biotic context in which to interpret severity. In this project, we evaluated two methods of mapping burn severity for four wildfires in western Montana using 64 plots as field reference: 1) an image-based burn severity mapping approach using the Differenced Normalized …

Carbon Cycling At The Landscape Scale: The Effect Of Changes In Climate And Fire Frequency On Age Distribution, Stand Structure, And Net Ecosystem Production., Michael G. Ryan, Daniel M. Kashian, Erica A.H. Smithwick, William H. Romme, Monica G. Turner, Daniel B. Tinker

Joint Fire Science Program Research Project Reports

Understanding the interactions between climate, fire and forest characteristics-- and how carbon dynamics are affected by these factors--remains an important challenge in ecology. As the size and severity of fires in the western US continues to increase (Westerling et al. 2006), it has become increasingly important to understand carbon dynamics in response to fire. In this study, we investigated these key interactions in the landscape of Yellowstone National Park (YNP). We asked how initial post-fire heterogeneity in forest structure (especially tree density and stand age) controls carbon dynamics over the full life cycle of individual forest stands, and how climate-mediated …

Delayed Tree Mortality Following Fire In Western Conifers, Sheri Smith, Danny Chuck, Elizabeht Reinhardt, Kevin Ryan, Charles Mchugh

Joint Fire Science Program Research Project Reports

We developed 3-year post-fire mortality models for 12 western conifer species by pooling data collected from multiple fire-injury studies. Models were developed for white fir, red fir, subalpine fir, incense cedar, western larch, lodgepole pine, whitebark pine, ponderosa pine, Jeffrey pine, sugar pine, Engelmann spruce, and Douglas-fir. Two sets of models were created, one for use in pre-fire planning where only crown injury and DBH were potential variables, and a second, optimal model for use in post-fire planning that used all significant variables. Predictive accuracy of all models was compared to the accuracy of the mortality model currently used in …

Effects Of Fuels Treatments And Wildfire On Understory Species And Fuels In The Ponderosa Pine Zone Of The Colorado Front Range, Paula Fornwalt, Merrill Kaufmann

Joint Fire Science Program Research Project Reports

The first clear indication that unnaturally dense forest conditions existed in ponderosa pine – Douglas-fir forests of the Colorado Front Range was the Buffalo Creek Fire, a large, catastrophic wildfire that burned in 1996. Ongoing research in the Front Range indicated that the Buffalo Creek Fire likely would have burned very differently under pre-settlement forest conditions; early photographs and written descriptions, as well as fire history and stand reconstruction data, all suggested that historically these forests were characterized by a matrix of low-density forests and shrubland or grassland openings that was created and maintained by a mixed-severity fire regime. As …

Effects Of Mechanically Generated Slash Particle Size On Prescribed Fire Behavior And Subsequent Vegetation Effects, Richy J. Harrod, David W. Peterson, Roger Ottmar, Peter Ohlson, Brad Flatten, Arlo Vanderwoude

Joint Fire Science Program Research Project Reports

Forest managers have begun to restore ecosystem structure and function in fire-prone ecosystems that have experienced fire exclusion, commodity based resource extraction, and extensive grazing during much of the 20th century. Mechanical thinning and prescribed burning are the primary tools for thinning dense stands and restoring pre-settlement forest structure, reducing the likelihood of devastating crown fires. Mechanical thinning can be costly when trees are nonmerchantable and prescribed burning can be risky unless fuel loadings are first reduced. Furthermore, stands that remain dense after commercial thinning can produce undesirable wildland fire- or even prescribed fire- effects on vegetation and soils. Land …