12244 research outputs found
Sort by
SEASONAL FLAMMABILITY COMPARISONS OF NATIVE AND EXOTIC PLANTS IN THE POST OAK SAVANNAH, BLACKLAND PRAIRIE, AND PINEYWOODS ECOREGIONS OF TEXAS
Get PDFEast Texas’ diverse landscape can present year-round wildfire seasons that can be influenced by seasonal and regional differences in climate and physiography. Greater insight into the fundamental thermal behavior of wildland fuels can aid in fire behavior prediction and development of fire-resistant plant lists. This study focused on estimating seasonal and regional flammability characteristics of five evergreen species: yaupon (Ilex vomitoria), Chinese privet (Ligustrum sinense), greenbrier (Smilax spp.), eastern red cedar (Juniperus virginiana), and escarpment live oak (Quercus fusiformis); and two deciduous species: Chinese tallow (Triadica sebifera) and southern red oak (Quercus falcata). Live foliar and small diameter branch wood samples were collected in the Pineywoods, Post Oak Savannah, and Blackland Prairie Ecoregions during the dormant (February) and growing (August) season. Oxygen bomb calorimetry (OBC) and proximate analyses estimated ash-free net heat content (NHC-AF; MJ kg-1) and proportions of volatile matter (VM%), fixed carbon (FC%), and ash percent (ash%). Pyrolytic and oxidative thermogravimetric analyses (TGA) estimated model-free activation energies (Ea(s)), relative spontaneous ignition temperature (RSIT; °C), gas-phase maximum mass loss rate (GP-MMLR; % min-1), and gas-phase combustion duration (GP-CD; min.). Greater mean VM% was a general indicator of greater mean NHC-AF(s) and GP-MMLR(s). All foliar NHC-AF(s), RSIT(s), and GP-MMLR(s) were significantly different with respect to species, season, and ecoregion. Mean regional GP-MMLR(s) were consistently greater in the growing season. The Post Oak Savannah and Blackland Prairie consistently yielded species with the greatest mean NHC-AF(s) and oxidative TGA values. Mean Ea(s) did not present any significant seasonal or regional trends
NATURAL REGENERATION DYNAMICS AND SURVIVAL INFLUENCED BY ABIOTIC AND BIOTIC FACTORS IN A BOTTOMLAND HARDWOOD FOREST
Get PDFRiparian ecosystems are vital to the landscape, providing critical services including water filtration and purification, flood and erosion control, carbon sequestration, biodiversity support, and aesthetic value. Bottomland hardwood forests, however, are threatened by invasive species, land loss/conversion, inconsistent or absence of harvesting disturbances, and altered hydrological patterns, leading to reduced success of desired, native species. This research assessed regeneration dynamics and one-year survival in a seasonally-flooded bottomland hardwood forest at Boggy Slough Conservation Area in East Texas to identify abiotic and biotic factors important for successful establishment of native regeneration. Areas sampled included two that were previously treated with herbicide for Chinese tallow (Triadica sebifera L.) and one untreated, reference area.
Shade-tolerant species were, in general, more common in the regeneration layer than shade-intolerant species. Less-desirable native species, such as water-elm (Planera aquatica J.F.Gmel.) and American hornbeam (Carpinus caroliniana Walt.) as well as invasive tallow were present at higher densities than many desired species. Oak species had low sapling densities, indicating potential recruitment issues throughout much of the site. The results showed that seedling densities of some native species, as well as Chinese tallow, varied among treatment areas, and that new cohorts of tallow regeneration may have been facilitated in the post-treatment environment at the expense of certain native species. Overcup oak (Quercus lyrata Walt.) seedlings were most abundant in the reference area. Other native indicator species in both treated and reference areas were mid-tolerant to tolerant of shade. Abiotic and biotic factors, representing complex moisture, light, and ground cover gradients, were associated with regeneration abundances of native species differently across sapling (DBH 0.6 to 3.9 inches), large seedling (DBH \u3c 0.6 inches, height ≥ 6 inches), and small seedling (DBH \u3c 0.6 inches, height \u3c 6 inches) size classes.
After one year, survival rates among native-hypogeal, native-epigeal, and invasive-Chinese tallow differed; Chinese tallow had a significantly lower survival rate than the native groups, likely as a result of weather events. Height and diameter increased the odds of survival for all regeneration groups. Additionally, vigor, down woody debris (DWD), microtopography, and canopy cover had varying influence among species groups. When significant, raised microsites increased odds of survival, while proximity to DWD and higher canopy cover decreased odds of survival. This research provided deeper insight into micro-site preferences of bottomland native tree species and which are projected to occupy the canopy in the future. To encourage regeneration of desired, native species, managers must be able to match species to site and create canopy openings sufficient to promote recruitment of native species without allowing competitive invasive species from claiming newly-available light and growing space
Texas Artists Joins the Soil Soldiers\u27: Three East Texas Artists in CCC Camps During the New Deal
Get PDF
Biometric Analysis of Emotional Responses and Cognitive Effort to Stimuli in Euhydrated versus Hypohydrated States
Get PDFThe purpose of this study was to examine the effects that hydration status, euhydrated versus hypohydrated, has on emotional responses and the intensity of these responses to three separate stimuli of a carbohydrate-electrolyte drink. Six male participants provided informed consent for participation. During a single trial of a walking dehydration exercise in an environmental chamber at 35℃, participants viewed three stimuli, pre and post exercise, consisting of a video commercial, three still images, and live viewing of a carbohydrate-electrolyte drink while reporting perceptual measures. Arousal and feeling states decreased from 3.89 to 2.50 and 3.83 to 2.17 (p = 0.02, p = 0.07 respectively) while perceptual need for fluid consumption increased from 42.67 to 90.67 (p = 0.004). Mental effort measurements, using fixations within the area of interest over time (seconds), increased across the video commercial and the still image viewing, with significance in image 1 and 3 from euhydrated to hypohydrated. Engagement scores increased insignificantly from euhydrated to hypohydrated across all stimuli. An inverse relationship was seen comparing perceptual measures in arousal and feeling states with mental effort and engagement. However, a linear relationship was seen with perceptual need to consume fluids with mental effort and engagement. The video commercial saw the most change, or increase, when compared to the other stimuli measured in both mental effort and engagement scores suggesting that the sensitivity of mental effort and emotional testing in regard to hypohydration was elicited with video stimuli as compared to other stimuli use
CHARACTERIZATION AND DELINEATION OF POTENTIAL EVAPORITE GEOHAZARDS USING ELECTRICAL RESISTIVITY METHODS ALONG FM 2185, CULBERSON COUNTY, TEXAS
Get PDFExtensive karst development within the Delaware Basin of West Texas and southeastern New Mexico poses a significant geohazard threat to infrastructure. Dissolution of regional evaporite strata have led to manifestations of karst geohazard phenomena including sinkholes, subsidence features, and caves. The study area is located within the Gypsum Plain in Culberson County, Texas, and includes outcrops of Castile and Rustler strata that host gypsum karst geohazards. Land reconnaissance surveys conducted during the summer of 2019 documented numerous surficial manifestations of karst features proximal to Farm to Market Road 2185 (FM 2185). In combination with traditional survey techniques, electrical resistivity methods were used to delineate karst features along a 48-kilometer segment of FM 2185.
Capacitively-Coupled Resistivity (CCR) and Direct-Current Resistivity (DCR) methods were used to characterize evaporite karst features that do not manifest surficially but pose potential geohazard concerns. CCR data was acquired using the Geometrics OhmMapper G-858 resistivity system, which uses a dipole-dipole configuration composed of five receivers connected by 2.5-meter coaxial cables and a transmitter offset of 2.5 meters. In combination with the medium analyzed, this geometric configuration enabled resistivity soundings up to 5 meters deep. DCR data was collected with a SuperSting (R8/IP) multi-electrode earth resistivity meter using 112 electrodes with 2-meter spacing and a dipole-dipole array configuration. This enabled a depth of investigation of up to 73 meters. Data was processed using AGI’s (Advanced Geometrics Inc.) EarthImager 2D software and used to delineate and characterize karst-related geohazards in the shallow subsurface within the study area
New Faculty Spotlight: Equity and Social Justice in SFA’s Department of Education Studies
No full textIn this session, five new faculty members in the Department of Education Studies at SFA share how they are working to foster equity and inclusion in their programs, research, and community. Their work is situated within both the elementary and secondary levels and various subject areas. The presenters will discuss how entering into faculty positions in the midst of a global pandemic and during a heightened climate of racial, political and civil unrest have shaped and informed their pedagogical practices. Their personal and collective interest in culturally responsive pedagogy and issues of equity, inclusion and social justice have enabled these professors to create and foster a community of collaboration
Challenging Conversations in the Classroom: A Faculty Panel
No full textAs educators seek to create thoughtful, informed global citizens, we must not shy away from difficult issues or from introducing students to a variety of critical perspectives. Facilitating such challenging conversations can be difficult. In this panel, we will examine the ways in which faculty across a variety of disciplines create structured and unstructured discussions and dialogues on issues such as race, ethnicity, gender, politics, science, and religion. Panelists will share how they prepare for such discussions, respond in tense moments, and foster open discourse
Opportunities and Rationale for Asian American Representation in 4th Grade Social Studies TEKS
Get PDFAs retired United States Air Force Major Arthur D. Jacob (n.d.) notes, “Their story must not be forgotten. It deserves to be told. To date, it remains shrouded in history.” As educators, we have the power to change that for our students and help them see themselves in the curriculum. In this paper, the researchers completed a structured vignette analysis to position themselves as they analyzed the 4th grade social studies TEKS for opportunities to combat the hegemonic narrative. We reviewed the TEKS to look for standards that allowed for countering this narrative and emerged with a practitioner plan for implementation that addresses the silenced narrative of Crystal City Japanese Internment Camp in Texas