Digital Commons Network^™

Complex Vegetation Dynamics At The Fire-Grazing-Drought Nexus, Christine H. Bielski

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The discipline of ecology long ago moved away from viewing systems as static entities where disturbance processes, environmental stochasticity, and spatiotemporal variability play minor roles in determining ecosystem structure and function. Ecological theory continue to develop frameworks and statistical techniques capable of describing the inherent complexity in natural systems. However, in dealing with the complexity in nature, many applied disciplines have yet to adopt such frameworks or statistical techniques. The objective of this study was bridge the gap between ecological theory and application by using complex systems theory to describe grassland vegetation dynamics at the fire-grazing-drought nexus. Chapters 2 and …

Using Ecological Production Functions To Link Ecological Processes To Ecosystem Services, Randall Jf Bruins, Timothy J. Canfield, Clifford Duke, Larry Kapustka, Amanda M. Nahlik, Ralf B. Schäfer

United States Environmental Protection Agency: Staff Publications

Ecological production functions (EPFs) link ecosystems, stressors, and management actions to ecosystem services (ES) production. Although EPFs are acknowledged as being essential to improve environmental management, their use in ecological risk assessment has received relatively little attention. Ecological production functions may be defined as usable expressions (i.e., models) of the processes by which ecosystems produce ES, often including external influences on those processes. We identify key attributes of EPFs and discuss both actual and idealized examples of their use to inform decision making. Whenever possible, EPFs should estimate final, rather than intermediate, ES. Although various types of EPFs have been …

Applications Of Time-Lapse Imagery For Monitoring And Illustrating Ecological Dynamics In A Water-Stressed System, Emma Brinley Buckley

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

Understanding and perceiving the natural world is a key part of management, policy, conservation, and inevitably for our future. Increased demand on natural resources has heightened the importance of documenting ecosystem changes, and knowledge-sharing to foster awareness. The advancement of digital technologies has improved the efficiency of passive monitoring, connectivity among systems, and expanded the potential for innovative and communicative approaches. From technological progression, time-lapse imagery has emerged a valuable tool to capture and depict natural systems. I sought to enhance our understanding of a water-stressed system by analyzing imagery, in addition to integrating images with data visualization to illustrate …

Gaur (Bos Gaurus) Abundance, Distribution, And Habitat Use Patterns In Kuiburi National Park, Southwestern Thailand, Supatcharee Tanasarnpaiboon

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

Population status of gaur (Bos gaurus), a wild cattle, in most habitats where they are present, is still unknown. As the use of camera traps in wildlife studies are widespread, I developed photographic individual identification procedures and utilized encounter histories of gaur individuals from camera trap data to estimate gaur abundance and density using the spatially explicit capture-recapture analysis. The study was conducted at Kuiburi National Park, southwestern Thailand, comprised of dry evergreen forest, moist evergreen forest, and man-modified secondary forest during November 2013- January 2015. I conducted 71 direct observations in a savannah-like habitat area to observe …

Eastern Wild Turkey Nest Site Selection In Two Frequently Burned Pine Savannas, Andrew R. Little, Nathan P. Nibbelink, Michael J. Chamberlain, L. Mike Conner, Robert J. Warren

School of Natural Resources: Faculty Publications

Introduction: Reproductive success is a critical factor affecting avian demographics and can be influenced by many factors including nesting chronology, predation risk, and fine-scale nest site selection.

Methods: We modeled the relative influences of habitat-related covariates at six spatial scales (nest site: 15-, 40-, 80-, 120-, 160-, and 200-m radii) on Eastern wild turkey (Meleagris gallopavo silvestris) nest site selection in two pine savannas managed by frequent prescribed fire (≤3 years) in southwestern Georgia during 2011–2013.

Results: Nest site (15-m scale) habitat metrics (mean visual obstruction [cm] and canopy closure [%]) had the greatest influence on nest site …

Export Of Insect Ecosystem Services From Hayed Native Prairie, Wayne J. Ohnesorg

Department of Entomology: Dissertations, Theses, and Student Research

Natural areas, such as prairie, have the potential to provide the benefits of pest suppression and pollination for agricultural production. In Nebraska, prairie is often used for hay production. The impact of prairie hay production management practices on beneficial arthropods is not well understood. Four prairie hay meadows adjacent to row crop fields were selected in northeast Nebraska. The goal was to assess the impact of haying them on beneficial arthropods and the movement of natural enemies into adjacent crop fields. Three management practices were evaluated for hay harvested from prairie meadows one cut per growing season, two cuts per …

Bibliographia Phytosociologica Et Floristica Mongolia: Pars Iv, Werner Hilbig

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In Ergänzung zu den bisherigen drei Teilen der Bibliographie vegetationskundlicher, vegetationsökologischer, floristischer und pflanzengeographischer Arbeiten über die Mongolei wird in dieser Arbeit Teil IV der Bibliographie vorgelegt. Er umfasst im Wesentlichen den Zeitraum 2007 bis 2014. Auch Publikationen zur Vegetationsgeschichte und zum botanischen Naturschutz werden berücksichtigt.

English summary:

In addition to the hitherto existing three parts of the bibliography of geobotanical, ecological, floristic and plant-geographical papers on Mongolia the part IV of the bibliography is given. It comprises in the main point the period from 2007 until 2014. In addition, publications on vegetation history and botanical nature protection are considered.

Hydrothermal Monitoring In Yellowstone National Park Using Airborne Thermal Infrared Remote Sensing, C. M. U. Neale, C. Jaworowski, H. Heasler, S. Sivarajan, A. Masih

Daugherty Water for Food Global Institute: Faculty Publications

This paper describes the image acquisition and processing methodology, including surface emissivity and atmospheric corrections, for generating surface temperatures of two active hydrothermal systems in Yellowstone National Park. Airborne thermal infrared (8–12 μm) images were obtained annually from 2007 to 2012 using a FLIR SC640 thermal infrared camera system. Thermal infrared image acquisitions occurred under clear-sky conditions after sunset to meet the objective of providing high-spatial resolution, georectified imagery for hydrothermal monitoring. Comparisons of corrected radiative temperature maps with measured ground and water kinetic temperatures at flight times provided an assessment of temperature accuracy. A repeatable, time-sequence of images for …

Endangered Species Research In Hawaii: The Early Years (1965–87), Michael J. Scott, Cameron B. Kepler

United States Geological Survey: Staff Publications

Hawaii is an ecologically isolated archipelago 2,500 miles from the nearest continent. Its isolation resulted in a taxonomically unbalanced flora and fauna with remarkable examples of adaptive radiation among those groups of organisms that won the dispersal sweepstakes. It was one of the last oceanic island groups to be populated by humans, about 900 A.D. by Polynesian travelers and in 1778 by Europeans. Relatively recent colonization by humans did not save it, however, from the biodiversity losses suffered by other isolated archipelagos—it only delayed them (Scott and others, 1988; Pratt and others, 2009a).

Patuxent’S Long-Term Research On Wolves, David L. Mech

United States Geological Survey: Staff Publications

The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species. Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota. Endangered Species Act protection of the wolf fostered its …

The Influence Of A Severe Reservoir Drawdown On Springtime Zooplankton And Larval Fish Assemblages In Red Willow Reservoir, Nebraska, Jason A. Deboer, Christa M. Webber, Taylor A. Dixon, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Reservoirs can be dynamic systems, often prone to unpredictable and extreme waterlevel fluctuations, and can be environments where survival is difficult for zooplankton and larval fish. Although numerous studies have examined the effects of extreme reservoir drawdown on water quality, few have examined extreme drawdown on both abiotic and biotic characteristics. A fissure in the dam at Red Willow Reservoir in southwest Nebraska necessitated an extreme drawdown; the water level was lowered more than 6 m during a two-month period, reducing reservoir volume by 76%. During the subsequent low-water period (i.e., post-drawdown), spring sampling (April-June) showed dissolved oxygen concentration was …