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The Robert B. Gordon Natural Area For Environmental Studies, Erika Szonntag

Gordon Natural Area History & Strategic Plan Documents

No abstract provided.

Geographic Patterns Of At-Risk Species, Curtis H. Flather, Michael S. Knowles, Jason Mcnees

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

This technical document supports the Forest Service’s requirement to assess the status of renewable natural resources as mandated by the Forest and Rangeland Renewable Resources Planning Act of 1974. It updates past reports on the trends and geographic patterns of species formally listed as threatened or endangered under the Endangered Species Act of 1973. We compare the geographic occupancy of threatened and endangered species at the county-level against the geographic occupancy of a broader set of species thought to be at risk of extinction. This is done to determine if new areas where species rarity may be concentrated emerge. Here …

Evaluating Forest Harvesting To Reduce Its Hydrologic Impact With A Spatial Decision Support System, Yanli Zhang, P. K. Barten, Ramanathan Sugumaran

Faculty Publications

Timber harvesting changes the condition of forest ecosystems, which are a major influence on the characteristics of headwater streams. Such characteristics include the quantity and timing of base flow and storm flow, concentrations of sediment and dissolved nutrients, water temperature, and the stability of the stream channels. This paper explores previous studies dealing with the relationship between timber harvesting and its hydrologic effects, especially long term water yield increase. The watershed disturbance threshold theory is raised and investigated in detail. The development and evaluation of a spatial decision support system, the Harvest Schedule Review System (HSRS), is then described. The …

A Unique Old-Growth Ponderosa Pine Forest In Northern Arizona, Scott R. Abella

Public Policy and Leadership Faculty Research

Old-growth ponderosa pine (Pinus ponderosa) forests are uncommon in the Southwest, and only one oldgrowth forest (the Gus Pearson Natural Area [GPNA]) has been researched in the ponderosa pine belt surrounding the city of Flagstaff in northern Arizona. The purpose of this study was to measure soil characteristics, current and pre-Euro-American settlement (1885) tree structure, and understory plant composition in a 6-ha remnant old-growth forest on volcanic, red cinder soils. Soil bulk density was extremely low (0.21 Mg/m3) in this forest because of high volumetric contents of cinders >2 mm diameter. As a result, volumetric soil moisture, organic C, and …

Homestead National Monument Of America Bur Oak Forest Restoration Plan: Reference Condition And Management Considerations, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The Vegetation Management Action Plan for Homestead National Monument of America includes a statement of the desired future condition that states: "The monument's natural resources are managed in such a way as to maintain a heterogeneous landscape composed of a mosaic of high quality remnant and restored tallgrass prairie, lowland bur oak forest and associated ecotones, as well as prairie streams and their hydrologic processes; that reflects the value of the site as a homestead, represents as accurately as possible the environment encountered by early settlers, and preserves native biodiversity" (Bolli 2006). The lowland bur oak forest along Cub Creek …

Wind Damage And Salinity Effects Of Hurricanes Katrina And Rita On Coastal Baldcypress Forests Of Louisiana, William Conner, Thomas W. Doyle, Richard H. Day, Ken W. Krauss, Christopher M. Swarzenski

Publications

The frequency of hurricane landfall in a given coastal stretch may play a more important role in the ecology of coastal forests than previously thought because of direct and indirect impacts of fallen trees and the introduction of salt water that lingers long after the storm passes. Findings show that surge events can inundate interior freshwater forests many miles from the coast and elevate soil salinities twofold to threefold. These elevated salinities may contribute to delayed mortality of certain tree species and set the stage for eventual forest decline and dieback.

Protecting Soil And Water In Forest Road Management, J. M. Grace Iii, B. D. Clinton

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

The National Forest road system is the network that supports public recreation, which has become the primary use of the public lands. The pattern of use of National Forest roads for recreation has increased dramatically since the late 1940s and is expected to continue to increase beyond the rates observed today. However, research over the past 60 years clearly presents forest roads as a major source of sediment and soil erosion from forest watersheds. Threats to healthy forests have received increased attention in the past decade. In particular, roads, road management, and travel management will likely be critical to addressing …

Structural Response Of Caribbean Dry Forests To Hurricane Winds: A Case Study From Guanica Forest, Puerto Rico, Skip Van Bloem, Ariel E. Lugo, Peter G. Murphy

Publications

Aim

Tropical dry forests in the Caribbean have an uniquely short, shrubby structure with a high proportion of multiple-stemmed trees compared to dry forests elsewhere in the Neotropics. Previous studies have shown that this structure can arise without the loss of main stems from cutting, grazing, or other human intervention. The Caribbean has a high frequency of hurricanes, so wind may also influence forest stature. Furthermore, these forests also tend to grow on soils with low amounts of available phosphorus, which may also influence structure. The objective of this study was to assess the role of high winds in structuring …

Structural Response Of Caribbean Dry Forests To Hurricane Winds: A Case Study From Guanica Forest, Puerto Rico, Skip Van Bloem, Ariel E. Lugo, Peter G. Murphy

Publications

Tropical dry forests in the Caribbean have an uniquely short, shrubby structure with a high proportion of multiple-stemmed trees compared to dry forests elsewhere in the Neotropics. Previous studies have shown that this structure can arise without the loss of main stems from cutting, grazing, or other human intervention. The Caribbean has a high frequency of hurricanes, so wind may also influence forest stature. Furthermore, these forests also tend to grow on soils with low amounts of available phosphorus, which may also influence structure. The objective of this study was to assess the role of high winds in structuring dry …

Spatial Autocorrelation And Pseudoreplication In Fire Ecology, Amanda L. Bataineh, Brian P. Oswald, Mohammad M. Bataineh, Daniel Unger, I-Kuai Hung, Daniel Scognamillo

Faculty Publications

Fire ecologists face many challenges regarding the statistical analyses of their studies. Hurlbert (1984) brought the problem of pseudoreplication to the scientific community’s attention in the mid 1980’s. Now, there is a new issue in the form of spatial autocorrelation. Spatial autocorrelation, if present, violates the traditional statistical assumption of observational independence. What, if anything, can the fire ecology community do about this new problem? An understanding of spatial autocorrelation, and knowledge of available methods used to reduce the effect of spatial autocorrelation and pseudoreplication will greatly assist fire ecology researchers.

A Practical Look At The Variable Area Transect, Solomon Z. Dobrowski, Shannon K. Murphy

Forest Management Faculty Publications

The variable area transect (VAT) is a plotless density estimator that has received little attention in the ecological literature despite having potentially robust estimation properties. VAT allows for density estimations without the lengthy search times associated with other plotless density estimators. In spite of this, little has been written about the effect of varying transect widths on its density estimation properties or on the practical implementation of the VAT in field settings. An artificial population sampler was used to examine the effect of transect width on density estimates obtained using the VAT. Three transect widths were chosen corresponding to the …

The Effect Of Scaling-Up On Remotely Derived Leaf Area Index Estimators In The Brazilian Amazon, John I. Menzies

All-Inclusive List of Electronic Theses and Dissertations

This research compared a traditional statistical technique with artificial neural networks to determine their effectiveness for modeling LAI in the Santarem region of the Brazilian Amazon. In addition, different satellite sensors in the form of ETM+, ASTER, MO DIS, and IKONOS were used to assess if spatial and spectral resolutions play a role in the ability to estimate LAI. This study focused on the following: (1) Determining if neural networks perform more accurately than multiple regression for LAI modeling (2) the effectiveness of different resolution satellite data including ETM+, ASTER, MODIS, and IKONOS for LAI estimation; (3) determining if spatial …

Ecological Studies Of Wolves On Isle Royale, 2004-2005, Rolf O. Peterson, John A. Vucetich

Ecological Studies of Wolves on Isle Royale

Annual Report 2004-2005

Wildland Fire In Ecosystems Effects Of Fire On Soil And Water, Jan L. Beyers, James K. Brown, Matt D. Busse, Leonard F. Debano, William J. Elliot, Peter F. Folliott, Gerarld R. Jacoby, Jennifer D. Knoepp, Johanna D. Landsberg, Daniel G. Neary, James R. Reardon, John N. Rime, Peter R. Roichaud, Kevin C. Ryan, Arthur R. Tiedemann, Malcolm J. Zwolinski

Joint Fire Science Program Synthesis Reports

This state-of-knowledge review about the effects of fire on soils and water can assist land and fire managers with information on the physical, chemical, and biological effects of fire needed to successfully conduct ecosystem management, and effectively inform others about the role and impacts of wildland fire. Chapter topics include the soil resource, soil physical properties and fire, soil chemistry effects, soil biology responses, the hydrologic cycle and water resources, water quality, aquatic biology, fire effects on wetland and riparian systems, fire effects models, and watershed rehabilitation.

Historical Evidence Of Riparian Forests In The Great Plains And How That Knowledge Can Aid With Restoration And Management., Elliot West, Greg Ruark

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

While some argue that the Great Plains were dominated by grasslands and that riparian woodlands were rare, others contend that trees would logically have occurred in riparian areas due to favorable microenvironment conditions. Historically, what native plant communities were found in riparian zones of the Great Plains? The answers to this question depend to a large extent on what time period is used as a reference of pre-settlement conditions.

The U.S. Fish and Wildlife Service (1981) drew upon conditions in 1905 for insight and concluded that trees were “wholly absent” or consisted of scattered cottonwood and willow. However, such a …

Effects Of Silvicultural Practices On Soil Carbon And Nitrogen In A Nitrogen Saturated Central Appalachian (Usa) Hardwood Forest Ecosystem, Frank S. Gilliam, David A. Dick, Michelle L. Kerr, Mary Beth Adams

Biological Sciences Faculty Research

Silvicultural treatments represent disturbances to forest ecosystems often resulting in transient increases in net nitrification and leaching of nitrate and base cations from the soil. Response of soil carbon (C) is more complex, decreasing from enhanced soil respiration and increasing from enhanced postharvest inputs of detritus. Because nitrogen (N) saturation can have similar effects on cation mobility, timber harvesting in N-saturated forests may contribute to a decline in both soil C and base cation fertility, decreasing tree growth. Although studies have addressed effects of either forest harvesting or N saturation separately, few data exist on their combined effects. Our study …

The Effects Of Habitat Resolution On Models Of Avian Diversity And Distributions: A Comparison Of Two Land-Cover Classifications, Joshua Lawler, Raymond O'Connor, Carolyn Hunsaker, K. Bruce Jones, Thomas Loveland, Denis White

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Quantifying patterns is a key element of landscape analysis. One aspect of this quantification of particular importance to landscape ecologists is the classification of continuous variables to produce categorical variables such as land-cover type or elevation stratum. Although landscape ecologists are fully aware of the importance of spatial resolution in ecological investigations, the potential importance of the resolution of classifications has received little attention. Here we demonstrate the effects of using two different land-cover classifications to predict avian species richness and the occurrences of six individual species across the conterminous United States. We compared models built with a data set …

Genetic Diversity And Structure Of The Fisher (Martes Pennanti) In A Peninsular And Peripheral Metapopulation, Samantha M. Wisely, Steven W. Buskirk, Gregory A. Russell, Keith B. Aubry, William J. Zielinsky

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Evolutionary processes can be strongly affected by landscape features. In vagile carnivores that disperse widely, however, genetic structure has been found to be minimal. Using microsatellite DNA primers developed for other mustelids, we found that populations of a vagile forest carnivore, the fisher (Martes pennanti), exhibit high genetic structure (F_ST = 0.45, SE = 0.07) and limited gene flow (Nm < 1) within a .1,600-km narrow strip of forested habitat; that genetic diversity decreases from core to periphery; and that populations do not show an equilibrium pattern of isolation-by-distance. Genetic structure was greater at the periphery than at the core of the distribution and our data fit a 1-dimensional model of stepping-stone range expansion. Multiple lines of paleontological and genetic evidence suggest that the fisher recently (<5,000 years ago) expanded into the mountain forests of the Pacific coast. The reduced dimensionality of the distribution of the fisher in western coastal forests appears to have contributed to the high levels of structure and decreasing diversity from north to south. These effects were likely exacerbated by human-caused changes to the environment. The low genetic diversity and high genetic structure of populations in the southern Sierra Nevada suggest that populations in this part of the geographic range are vulnerable to extinction.

Species Pairwise Associations Over Nine Years Of Secondary Succession: Assessing Alternative Explanations And Successional Mechanisms, Lara R. Rozzell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The importance and mechanisms of species interactions are undetermined in most successional systems. I used correlations and null modeling to detect pairwise species associations between 33 plant species in the first nine years of secondary succession after logging and burning in a western Oregon Cascade forest. I tested for correlations between each species and soil nutrients, nonvegetative ground cover, and surrounding vegetation. More positive than negative associations were found at all sampling times. The proportion of positive associations decreased and negative associations increased through time. Up to 42% of associations at a sampling time were explicable by shared positive correlations …

Plumeless Thistle (Curled Thistle, Bristly Thistle), L.-T. Kok, A. Gassmann

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Plumeless thistle, Carduus acanthoides L., is an introduced Eurasian noxious weed in pastures, rangelands, croplands, and along highways in 19 of the contiguous states in the United States (Frick, 1978). Carduus acanthoides and Carduus nutans L. in the northeastern United States often occupy the same habitats, such as overgrazed pastures and disturbed roadsides, and these species sometimes occur as mixed stands.

Forested Wetlands Of The Southern United States: A Bibliography, William Conner, Nicole L. Hill, Evander M. Whitehead, William S. Busbee, Marceau A. Ratard, Mehmet Ozalp, Darrell L. Smith, James P. Marshall

Publications

The term forested wetland covers a variety of forest types including mangroves, cypress/tupelo swamps, bottomland hardwoods, pocosins and Carolina bays, flatwoods, and mountain fens. These forests are dominated by woody species that have morphological features, physiological adaptations, and/or reproductive strategies enabling them to achieve maturity and reproduce in an environment where the soils within the rooting zone may be inundated or saturated for various periods during the growing season. Although alluvial floodplains occur along most streams of the United States, they are most extensive in the Atlantic Coastal Plain, Gulf Coastal Plain, and Mississippi Alluvial Plain. Only about half of …

Comparison Of Rodent Communities Of Native Brushland, Replanted, And Secondary Succession Sites In The Lower Rio Grande Valley Of Texas, Mitchell Allen Sternberg

Theses and Dissertations - UTB/UTPA

I compared small mammal communities between mature brushlands, replanted brushlands, and secondary succession sites from November 1998 to December 1999 to evaluate revegetation efforts in the Lower Rio Grande Valley of Texas. I determined rodent community characteristics of the three habitat types. The mature brushland and replanted habitats had similar species diversities and both were significantly higher than the secondary succession habitat. Species diversity was highest at the replanted edge grid during Winter. The current replanting method provides a more diverse rodent community than does natural succession from fallow fields. Wildlife monitoring should be extended to other taxonomic guilds so …

Development, Testing, And Implementation Of The Temple-Inland, Inc. Sustainable Forest Management System (Tinsms), 2001, Arthur Temple College Of Forestry And Agriculture

eBooks

No abstract provided.

Persistence Of Aspen Regeneration Near The National Elk Refuge And Gros Ventre Valley Elk Feedgrounds Of Wyoming, D.T. Barnett, T.J. Stohlgren

Aspen Bibliography

We investigated aspen (Populus tremuloides) regeneration in the Gros Ventre River Valley, the National Elk Refuge, and a small part of Grand Teton National Park, Wyoming, to see if elk (Cervus elaphus) browsing was as damaging as previously thought. We conducted a landscape-scale survey to assess aspen regeneration across gradients of wintering elk concentrations using 68 randomly selected aspen stands in the 1,090 km2 study area. Forty-four percent of the stands sampled supported regeneration of saplings (stems greater than 2 m in height but less than 10 cm in diameter). There were no significant differences of regeneration across elk winter …

Long-Term Aspen Exclosures In The Yellowstone Ecosystem, Charles E. Kay

Aspen Bibliography

Aspen has been declining in the Yellowstone Ecosystem for more than 80 years. Some authors have suggested that aspen is a marginal plant community in Yellowstone and that recent climatic variation has adversely affected aspen, while others contend that excessive browsing by native ungulates is primarily responsible for aspen’s widespread decline. To test these hypotheses, I measured all the long-term aspen exclosures (n = 14) in the Yellowstone Ecosystem. Aspen stands inside all exclosures successfully produced new stems greater than 2 m tall without fire or other disturbance, while few outside stands successfully regenerated due to repeated browsing. Understory species …

The Breeding Ecology Of White-Faced Ibis In The Lower Carson River Basin, Nevada, Eric Patrick Kelchlin

LSU Historical Dissertations and Theses

The Great Basin White-faced Ibis (Plegadis chihi) population is recognized as a Species of Management because of its small population size, limited number of traditional breeding sites, and vulnerability to habitat loss. The ability to predict future population trends and develop wetland management strategies is limited because many aspects of their breeding ecology and population dynamics are unknown. 1 examined White-faced Ibis nesting ecology and breeding habitat selection at the Lower Carson River Basin, Nevada, from 1995-1997, and the relationship between the local surface water conditions and trends in the number of breeding pairs from 1970-1997 on a local and …

Seasonal Comparison Of Remotely Sensed Relative Forest Ecosystem Temperature Zones With Topography And Forest Biomass In The Clear Springs Wilderness Area Of The Shawnee National Forest, Daniel Unger

Faculty Presentations

The use of thermal infrared data to delineate seasonal relative forest ecosystem temperature zones as a tool for forest ecological studies was analyzed. Analysis involved: (1) delineating relative seasonal forest ecosystem temperature zones within the Clear Springs Wilderness Area of the Shawnee National Forest using Landsat Thematic Mapper thermal infrared data; and, (2) quantifying the effect of topography and forest biomass on relative forest ecosystem temperature zones within seasons. Results indicate that slope was statistically uncorrelated with relative temperature zones within any season, aspect was statistically correlated with relative temperature zones during fall and winter, and forest biomass was statistically …

Delineating Relative Temperature Zones In Forest Ecosystems: An Adaptation And Evaluation Of Current Methodologies, Daniel Unger, J.J. Ulliman

Faculty Publications

The effectiveness of using: (1) thermal infrared data; (2) potential solar radiation: and. (3) predicted temperature for mapping relative temperature zones in forest ecosystems were evaluated as tools for forest ecology studies.

The computer simulation models SOLAR and MTCLIM were found to be ineffective for mapping relative forest ecosystem temperature zones. SOLAR-calculated potential solar radiation and MTCLIM-predicted temperature were found to be statistically uncorrelated with coincident mean maximum daily forest ecosystem ambient air temperature recorded within the University of Idaho Experimental Forest during June and July, 1993. Landsat Thematic Mapper thermal infrared data were shown to be effective for mapping …

Development And Validation Of Forest Habitat Models In The Uinta Mountains, Utah, Tracey S. Frescino

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A significant question currently facing environmental managers is how to accurately and efficiently quantify forest diversity and resources. Numerous studies have demonstrated the use of modern spatial analytical tools, such as geographical information systems (GIS), remote sensing devices, and statistical models for predicting the distribution of dominant vegetation cover types. This study examines the ability of generalized additive models (GAMs) to delineate structural diversity in forested ecosystems (specifically the Uinta Mountain Range in Utah) using GIS tools and satellite spectral data, and analyzes the effect of including different forms of satellite data in model construction (i.e., Landsat thematic mapper (TM), …

Comparison Of Presettlement And Present Vegetation Cover Of Marion County, Illinois Using A Geographic Information System, Daniel Unger

Faculty Presentations

The vegetation types of Marion County, Illinois prior to European settlement, which were derived from soil association surveys, were compared to a satellite map of current vegetation types to quantify their change over time. GIS analysis indicates that 10% of presettlement prairie is currently grassland, 2% of presettlement prairie has been converted to forest, 32% of original prairie has been converted to agriculture and urban use, 17% of presettlement forest remains intact, grassland comprises 18% of presettlement forest while 21% of presettlement forest has been converted to agricultural and urban use.