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Full-Text Articles in Life Sciences
Disturbance Ecology And Vegetation Dynamics At Varying Spatial And Temporal Scales In Southern Rocky Mountain Engelmann Spruce Forests, R. Justin Derose
Disturbance Ecology And Vegetation Dynamics At Varying Spatial And Temporal Scales In Southern Rocky Mountain Engelmann Spruce Forests, R. Justin Derose
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
High-severity disturbances are the primary drivers of Engelmann spruce-subalpine fir ecosystems in the southern Rocky Mountain. Recently, an unprecedented, landscape-wide (at least 250 km2) spruce beetle outbreak killed virtually all the Engelmann spruce on the Markagunt Plateau in southwestern Utah, USA. Results from dendroecological analyses suggested the combination of antecedent disturbance history and drought-driven stand development was responsible for creating suitable host conditions prior to the recent outbreak. Multiple and consistent lines of evidence suggested mixed- and high-severity fires shaped the development of the Markagunt Plateau. Subsequent stand development, influenced by species-specific differential tree-ring response to drought, resulted in the …
Population Ecology And Reproductive Biology Of The Diamondback Watersnake, Nerodia Rhombifer (Serpentes: Colubridae), In Southernmost Texas, Ruben D. Zamora
Population Ecology And Reproductive Biology Of The Diamondback Watersnake, Nerodia Rhombifer (Serpentes: Colubridae), In Southernmost Texas, Ruben D. Zamora
Theses and Dissertations - UTB/UTPA
Nerodia rhombifer is a polytypic, semi-aquatic snake with a broad geographical distribution ranging from the American Midwest southward to Chiapas, Mexico. Although relatively abundant throughout much of its range, few ecological studies of the species have been conducted. This study provides basic population ecology information in a subtropical habitat. Population data were obtained in a mark-recapture study at Santa Ana National Wildlife Refuge, Hidalgo County, Texas, from August 1995 to December 1998. Specimens taken elsewhere in Hidalgo County provided information on the reproductive biology. This study provides the first absolute density estimates from anywhere within the species’ range. Quantitative information …
The Influence Of Environmental Factors On The Activity And Movement Of Bufo Nebulifer (Coastal Plain Toad) In A Disturbed Area, Crystal Salinas
The Influence Of Environmental Factors On The Activity And Movement Of Bufo Nebulifer (Coastal Plain Toad) In A Disturbed Area, Crystal Salinas
Theses and Dissertations - UTB/UTPA
Toads in the family Bufonidae are poorly studied in southern Texas. Bufo nebulifir, a native bufonid, has been studied in its northern and southern range limits (east Texas and northern Mexico). South Texas' sub-tropical climate could impact the length of the activity period for B. nebulifer in yet unrecorded ways. This study resolves whether environmental factors correlate to Bufo nebulifer's activity, presence, and movement, using a mark-recapture method. The study was conducted for one year during February 2008 to March 2009. Environmental factors, especially rainfall and temperature were significantly correlated (PB. nebulifer . The active period of B. …
Determination Of Dispersal Patterns Of The Small-Mouthed Salamander (Ambystoma Texanum) In Eagle Creek Park (Indianapolis, In), Stacey Diane Summitt
Determination Of Dispersal Patterns Of The Small-Mouthed Salamander (Ambystoma Texanum) In Eagle Creek Park (Indianapolis, In), Stacey Diane Summitt
Undergraduate Honors Thesis Collection
Urbanization and the increasing threat of habitat fragmentation are contributing to the significant declines in amphibian populations world-wide. Ambystomatid species are particularly susceptible to habitat fragmentation because they migrate yearly across upland forests to their breeding sites. Habitat changes could be altering the genetic structure in these species; however few studies have focused on this topic and more generally, examined the dispersal patterns of Ambystomatids. In 2003, Clark, Cripe, and Stachniw conducted a study on “Metapopulation Structure of Ambystoma texanum in Eagle Creek Park (Indianapolis, IN) and the Potential for Gene Flow.” They hypothesized that distance limits the dispersal of …
Biology And Ecology Of Wild Radish (Raphanus Raphanistrum), Mayank Malik
Biology And Ecology Of Wild Radish (Raphanus Raphanistrum), Mayank Malik
All Dissertations
Wild radish ( L.), a facultative winter annual is a troublesome weed in small grain crops of the Southeastern United States. Besides being a weed, it may also be used as a cover crop for weed management due to its production of glucosinolates. Studies were conducted to evaluate the biology and ecology of wild radish as well as its glucosinolate production and its weed management possibilities.
Wild radish emerging in fall months formed a rosette of leaves which aided its winter survival. Plants emerging from December through March that did not form a rosette had minimal survival. Wild radish life …
Differential Response Of Amp Activated Protein Kinase (Ampk) And Hsp70 To Temperature Stress In The Gastropod, Nucella Lapillus, Emily Zimmermann
Differential Response Of Amp Activated Protein Kinase (Ampk) And Hsp70 To Temperature Stress In The Gastropod, Nucella Lapillus, Emily Zimmermann
All Theses And Dissertations
Populations of the gastropod Nucella lapillus are polymorphic for shell color, with light-colored shells predominating on warmer, wave-protected shores and dark-colored shells limited primarily to cooler, wave-exposed shores. During thermal stress, darker shells attain higher body temperatures than lighter shells. These results suggest that heat stress may determine field distribution patterns. However, there is currently little evidence of physiological consequences of thermal stress in these organisms. Following the guiding hypothesis that heat stress leads to cellular energy depletion, we explored whether the central energy regulator AMP-activated Protein Kinase (AMPK) is activated by heat stress. We compared this response in both …
Characterization Of Aerobic Respiration In Great Basin Hot Springs, Caitlin N. Murphy
Characterization Of Aerobic Respiration In Great Basin Hot Springs, Caitlin N. Murphy
UNLV Theses, Dissertations, Professional Papers, and Capstones
Despite a wide diversity of possible electron donors available to fuel chemolithotrophy, it has been proposed that hydrogen is the single most important electron donor in geothermal ecosystems. To directly test this hypothesis, a simple system was devised to determine whether microorganisms in hot spring water and sediment are capable of using hydrogen and other electron donors for aerobic respiration using microrespirometry. The protocol for these experiments was developed using pure cultures of Thermocrinis ruber to determine the effect of growth conditions on the rate of oxygen consumption following the addition of electron donors. For field experiments, samples were collected …