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Item A comparison of system designs and operations for the transmission of large volumes of water to West Texas(Texas Tech University, 1969-08) Lovell, Troy LynnNot availableItem A petrographic comparison of the Lower Spraberry and the Dean Siltstones of the northern Midland Basin of West Texas(Texas Tech University, 1955-08) Tucker, Charles OdellNot availableItem A Study of the Silurian System and a Silurian Reef in West Texas and Southern New Mexico(Texas Tech University, 1971-05) Cronin, Thomas C.Not Available.Item Cattle grazing and biosolids in West Texas(Texas Tech University, 2004-05) Avila, Jose-MiguelLime stabilized biosolids applications on rangelands were evaluated by cattle grazing in 2000 and 2001 on six, 16-ha pastures. Three pastures were treated with 20 dry ton per ha and 3 untreated pastures were used as a control. Average daily gain of steers grazed on test pastures for 120 days were evaluated through two grazing seasons. Forage samples were collected to determine forage availability and forage quality. At the end of each performance trial, animal tissues were collected from liver, muscle, kidney, and heart to evaluate trace elements. An additional four, 8-ha pastures were used to document animal behavior. Each of these four pastures was divided in half. Biosolids was applied in one half of the pasture at 20 dry ton/ha; the other half was untreated. Animal behavior was evaluated in 4-day consecutive periods, during 12 hours of direct observations at the beginning and end of each grazing season of the performance trial. Average daily gain was similar (P>0.05) between treated and untreated areas with 0.249 and 0.238 kg per animal and with 0.140 and 0.139 kg per ha in year 2000, as well as 0.435 and 0.377 kg per animal and 0.154 and 0.118 kg per ha in year 2001. Tissue samples from steers grazing on treated pastures were similar in trace elements (P>0.05) compared with those collected on untreated pastures. The steers spent 5 hours and 40 minutes per day grazing in 2000 with 57% of grazing time spent in the biosolids-treated area. In 2001, steers spent 6 hours and 53 minutes grazing with 56% of grazing time spent in the biosolids area. In conclusion, biosolids affect animal performance when conditions are favorable especially rainfall and temperature. However, steer grazing behavior showed preferences for grazing activities on the biosolids areas. Biosolids applications positively affect forage quality, especially crude protein.Item Cold frontal passages across the Texas High Plains: characteristic behavior and possible causes(Texas Tech University, 1995-12) Fano, Steven JForecasters on the Texas High Plains have noted that cold fronts often appear to slow down during the daytime hours and accelerate at night. The extent to which cold fronts systematically behave in this manner is the focus of this investigation. Similar studies conducted for the Eastern Plains of Colorado conclude that cold fronts are most likely to experience diurnal variation in movement during the warmest months of the year when upper-level dynamical forces are least influential. Hence, the atmosphere's response to daytime surface heating is deemed most responsible for affecting cold frontal strength and speed of propagation. One such response to surface heating is the growth of the convective mixed layer which acts to erode the leading edge of the colder air mass, causing the front to appear to slow, stall or even retrogress. Another response comes from the unequal heating of the earth's surface over sloping terrain. This process creates a shift in the surface geostrophic wind from a northerly component at night to a southerly component during the day. The northerly flow aids in nighttime frontal progression while the daytime southerly component opposes frontal movement. Certain cold fronts may also behave as density currents, propagating under their own weight. The hydrostatic pressure behind these fronts is in constant battle with dynamic pressures out ahead of it. Propagation of the cold front may be slowed or stopped if the opposing pressure equals or exceeds the hydrostatic pressure behind it. The investigation looks at Texas High Plains cold frontal passages by means of case studies and climatology. Cold fronts whose movements were altered to some extent during the daytime comprised the three case studies. These spring and summertime cold fronts all had very weak upper-level dynamics associated with them and all were influenced to some extent by the boundary layer processes mentioned above. A climatology of all Texas High Plains cold frontal passages was then compiled for the years 1970 through 1990 in order to determine with what regularity cold fronts passed through Amarillo, Lubbock and Midland. Diurnal tendencies were evident to some extent in all seasons, but were most pronounced during the warmer months of the year.Item Conodont biostratigraphy of Devonian strata of West Texas and eastern New Mexico and the apparatus of early Devonian Icriodus species(Texas Tech University, 2002-08) Meyer, Beverly DianeDevonian strata in the Permian Basin reflect eperrogenic events and eustatic fluctuations in the southern midcontintent North America Changes in relative sea level demonstrated by conodont faunas and facies changes within the Frame, Thirtyone and Woodford Formations are compared to the Devonian qualitative eustatic curve. The lower Devonian (Lochkovian, woschmidit zone through omoalpha zone) conodont species Icriodus postwoschmidti Mashkova, 1968 occurs in carbonates of the Frame Formation in the Permian Basin and within the pre-Ia cycle of the eustatic curve. Icriodus claudiea Klapper, 1980 occurs in overlying carbonates and cherts of the Thirtyone Formation providing a Pragian (sulcatus to kindlei zone) age for the upper part of the formation and placing the Thirtyone in cycle Ia of the eustatic curve. Above the Thirtyone, green and gray clay shales at the base of the Woodford Formation produced an abundant Middle-Upper Devonian (Givetian-Frasnian) varcus to falsiovalis zone faima that ranges through cycle IIa into IIb of the sea-level curve. Typical Woodford black shales (Upper Devonian, Famennian) contain a crepida through expansa zone fauna of cycles IIe and IIf of the sea-level curve. No Mississippian conodont species were recovered from the Woodford Formation in the Permian Basin. Carbonate turbidites of the Dunple Limestone document headward erosion and transport of Woodford Formation deposits from the southern midcontment into a closing Ouachita ocean basm to the south or east during the Early Pennsylvanian. Four conodont faunas are described from reworked conodont elements recovered from the Dunple in the Marathon Uplift. Elements rangmg in age from Middle varcus Zone (Middle Devonian) to Lower crenulata Zone (Lower Mississippian) were admixed throughout the samples, with no original stratigraphic superposition preserved. The recovery of abundant elements of the Early Devonian species Icriodus postwoschmidti and I. claudiea from the Frame and Thutyone formations allows apparatus reconstmction and comparison of the morphological characteristics of the two species. Coryssognathus dubius (Rhodes, 1953) has been suggested as the most likely ancestor of Icriodus based on similar morphology of the non-Pa elements to those of the oldest species of the genus, I. woschmidti Ziegler, 1960. The apparatus reconstruction of I. postwoschmidti allows interpretation of changes in the apparatus that occurred between I. postwoschmidti and its ancestor species I. woschmidti, and suggests a relationship to C. dubius. Reconstruction of the apparatus of I claudiae allows comparison to both I. postwoschmidti and younger species and demonstrates continued morphological changes through time.Item Crustal xenoliths from Potrillo Maar: implications for evolution of continental crust beneath the southern Rio Grande rift(Texas Tech University, 2003-08) Chattopadhyay, IndraniThe mid-crustal xenoliths from Potrillo maar record a petrologic and geochemical history that has until now been unknown from the Potrillo volcanic field. The igneous and meta-igneous xenoliths are samples of one or more plutonic bodies that crystallized at depths from 7-14 km (middle to upper crust). The rock unit ranges in composition from hornblende biotite diorite to quartz monzonite and monzogranite; it is broadly alkalicalcic The initial Sr87Sr86 suggests that the source region is heterogeneous or that the parental magmas were contaminated by crustal material. At least three geochemical groups can be identified, primarily on the basis of silica content. There is considerable overlap between groups 1 and 2, and the boundary between these two groups cannot be distinguished graphically. The third group is granitic and is geochemically distinct from groups 1 and 2. A dioritic composition is thought to represent mafic parental magma. Its calculated liquidus temperature at 2% H2O and 4 Mpa pressure is 1172°C. The presence of fossiliferous limestone xenoliths indicates that the Potrillo maar eruption sampled rocks of late Paleozoic age. However, the age of marble and quartzite xenoliths are not known. The quartzite xenoliths are relatively undeformed, but isoclinal folding in some of the marble xenoliths suggests subsurface deformation that has not been observed in local surface exposures of metasedimentary rocks. One model proposed for the crust under the southern Rio Grande rift assumes that the marble is late Paleozoic in age. The fossiliferous limestones are late Paleozoic in age and are older than the plutonic rocks. The relative age of the deformed marbles in this model is not clear, it can be deformed with the plutonic rocks or due to an earlier regional extensional event. In the second model, marble is proposed to result from contact metamorphism in the aureole of a plutonic rock body at a depth of 7-14 km. The presence of marble and calc-silicate xenoliths in dioritic blocks is consistent with a correlation of the marble with surface exposures of the Castner Marble in the Franklin MountainsItem Degradation of pedogenic calcretes in West Texas(Texas Tech University, 2003-08) Hirmas, Daniel RNot availableItem Depth of Penetration of Nitrate Nitrogen and Phosphorus and Effects of Selected Liquid Fertilizer Applications on Yields of Milo, Wheat and Barley on a Dalhart Fine Sandy Loam, in West Texas(Texas Tech University, 1949-08) Walker, Harvey JNot Available.Item Determination of anion and cation concentrations in West Texas grapes(Texas Tech University, 1988-12) McDowell, William LThe decline of the Texas oil and agriculture industries has shown the need for the diversification of the Texas economy in order to expand the income base for the state government and state supported services. Historically, Texas has been a center of wine production the Southwest and boasted a significant "cottage industry" of wineries. Unfortunately, this occupation virtually vanished during the early part of the twentieth century. The wine industry is now enjoylng a rebirth and it has become obvious that the technology applicable to wine production in California and France can not be relied on in Texas owing to the unique growing conditions encountered in the vrticultural regions of western and Southwest Texas. As pH problems are a significant obstacle to the production of a commercially viable product, a integrated program of analysis to improve the understanding of the components involved in determining the pH of juice and wine was undertaken. Organic acid analysis was conducted by reversed phase HPLC while flame AA was used for the determination of metals. An ion exchange and subsequent titration method was used for gross charge determination. This method also served as a benchmark for comparison with the HPLC and AA methods. These techniques were used for monitoring changes in anion and cation content during maturation and vinlfication and for development of a simple method of calculating necessary corrections in acid levels of grape juice/ wine either by additions of tartaric acid or ion exchange. Comparison of the summation of cations or anions to the gross charge titration on a percentage basis was used as an appraisal of the completeness of analysis. This idea of "charge balance" comparison was also used for direct comparison of the cationic and and anionic analysis. In order to assess the degree of supersaturation of tartrate salts and to investigate the changes produced by acid additions to juices, several special treatments including chilling of juice, addition of acids and acid salts were performed on fresh juice samples. The results of these treatments were compared to wines after vinification.Item Ecology of sympatric mule deer and white-tailed deer in west-central Texas(Texas Tech University, 2004-12) Brunjes, Kristina JohannsenFluctuations in populations of sympatric mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus), as well as the potential for interspecific competition have fostered a need for information about the ecology of these unique populations to aid the development of management strategies. I estimated home range sizes, core area sizes, overlap, and survival of sympatric desert mule deer and white-tailed deer in west-central Texas. I captured 50 female mule deer, 53 female white-tailed deer, and 18 males of each species, fitted them with radio-collars, and monitored them for mortality from 2000 through 2003. I calculated home ranges for 7 males of each species in 2001 and 2002. Home range sizes of male deer (mule deer, 8.8 km^; white-tailed deer, 7.4 km^) were similar. Interspecific home range overlap was less common than intraspecific overlap. Mean annual survival was 0.76 ± 0.04 (mean + SE) for mule deer and 0.80 ± 0.06 for white-tailed deer. I estimated home range (95% kernel) and core area (50% kernel) sizes and overlap and survival of female deer. Average (+ SE) spring home range size of mule deer was 3.9 + 0.32 km"^ and white-tailed deer was 4.32 + 0.77 km^; summer home range sizes were 2.82 + 0.32 km^ and 2.08 + 0.23 km^, respectively. Interspecific seasonal home range overlap indices were similar to intraspecific overlap. Core area overlap also was similar within and between species during summer, but interspecific core area overlap was less common during spring. Mean (+ SE) annual survival of mule deer (0.91 + 0.08) was greater than survival of white-tailed deer ( 0.64 ± 0.10). Starvation and disease were the most commonly identified causes of death for males and females, suggesting improved quality and abundance of forage may be warranted to buffer environmental vagaries. However, significant spatial overlap indicated that tailoring management efforts to benefit just 1 species will require attention to the scale of intended activities. I evaluated the role of vegetation community structure and topography on the habitat use of sympatric deer in west-central Texas using information obtained from radio-collared deer and a geographic information system (GIS). Both species used habitat in a non-random fashion and exhibited species- and sex-specific preferences. Mule deer used habitats with less vegetation cover and more topographic diversity, while white-tailed deer avoided landscapes at higher elevations. Males of both species avoided areas with greatest vegetation cover including those areas containing permanent water sources, but females tended to use such areas, particularly during summer fawning. Differences observed in the smaller core area scale were not always detected at the larger home range level, indicating that decisions about habitat use were made at different spatial scales.Item Establishment and stress tolerance of buffalograss(Texas Tech University, 1995-12) Gaitan-Gaitan, FernandoBuffalograss [Buchloe dactyloides (Nutt.) Engelm.j is a well adapted species and one of the most drought tolerant grasses native to the semi-arid Southern Great Plains. Successful establishment of buffalograss is often limited by date of planting, seeding rate and type of seed. Buffalograss response to drought stress is to enter dormancy with very rapid regrowth when water becomes available. Characterization of other phenotypic responses to drought have not been established due to the lack of a suitable drought stress tolerance test. This dissertation presents the results of several studies conducted at the Texas Tech Plant Laboratory in Lubbock, Texas during three years to determine the optimal planting dates as well as seeding rates and type of seed to use. A modified tray system was designed to test buffalograss seedlings at two drought stress levels. Results indicated that when the cultivars 'Comanche' and Texoka' were used, optimal dates to obtain turfs with good stand density and quality are from mid May to mid July. Caryopses always produced higher stand establishment two and four weeks after planting. Experiments conducted to determine the optimal seeding rates and type of seed using 'Comanche' buffalograss indicated that rates of 1125 to 1875 caryopses m^"^ gave optimum stand establishment and turf quality. Caryopses had a faster emergence and had less seedling mortality than burrs. However, final density and turf quality were not affected by type of seed and planting rate . A test to assess the drought tolerance of buffalograss seedlings was designed modifying a PEG-based tray system used to measure drought tolerance in forage grasses. The modified test uses variable day/night temperatures and an open container to allow constant air movement at leaf level. After tests were performed on over 1000 seedlings in each of four populations, no significant differences between drought stress levels or populations were found. Seedling survival ranged from 0.6 to 1.5 percent measured after plants were rewatered. The system proved to be useful for buffalograss seedling screening with adequate calibration for type of soil used and chamber conditions.Item Evaluation of groundwater quality in Castro, Dawson, and Terry Counties $c by Ajay Ramachandran.(Texas Tech University, 2004-08) Ramachandran, AjayNot availableItem Evaluation of sucrose phosphate synthase transgenic cotton lines under field conditions in West Texas(Texas Tech University, 2004-05) Hamill, E MargaretNot availableItem Genotype evaluations for productivity and quality of peanut in West Texas(Texas Tech University, 2001-05) Howell, Bradley DeePeanut (Arachis hypogaea L.) acreage has rapidly increased on the Texas Southern High Plains. In 1995, there were only 17,806 hectares planted, however, in 1998, 76,893 hectares were planted. Yields have been greater than both state and national levels, averaging 3700 kg/ha. The production area is characterized as semi-arid, with rainfall averaging 450 mm per year. The relatively high elevation (approx. 900 m) and cool night temperatures result in a shorter growing season, a lack of adequate heat unit accumulation, and delayed maturity of the peanut crop. This research was designed to evaluate a wide range of genetic types for variation in yield, maturity, and oil quality under West Texas environmental conditions. The genetic material (consisting of 35 entries, including experimental and commercial lines) was grown in Terry County, Texas, southwest of Lubbock, Texas, In 1998, 1999, and 2000. In 1998, center pivot Irrigation was used while in 1999 and 2000, subsurface drip tape was used to provide irrigation. In all three years, irrigation was adequate to provide 6 mm per day, on a five-day frequency. Plots were 2 rows wide by 6 m long with 3 replications in 1998, and 2 rows wide by 13 m long with 4 replications In 1999 and 2000, with row spacing of 0.80 m all years. In 1998 and 1999, maturity was estimated using the Hull Scrape Method beginning at 85% of the "long-term average" (LTA) heat unit accumulation and continued at 5% intervals until 100% of the LTA heat unit accumulation had been reached. Yield was determined by harvesting the two rows with a commercial digger and threshing with a stationary small plot thresher. Oil was extracted from a sample of each plot to determine oil content. Fatty acids were methylated to form fatty acid methyl esters, which were then analyzed by gas chromatography. Oleic acid/linoleic acid ratios were calculated, along with unsaturated/saturated fatty acid ratios. Genotypic variation was present in yield, maturity, grades, oil content, U/S ratios, and 0/L ratios (P < 0.05). Large differences in yield were noted among genotypes and between years. 0/L ratios were considerably lower than those previously reported in other peanut production areas. Mean yields were plotted against mean grades (used as maturity indices) and divided into four quartiles. Thirteen entries fell into the quartile labeled as "high yield and early maturity." Four entries were high oleic genotypes with high yield and early maturity.Item Helminth community structure of mallards on the southern High Plains of Texas(Texas Tech University, 1993-08) Fedynich, Alan M.This study examined the effects of host age and season on community structure and pattern of helminths in mallards (Anas platyrhynchos) collected on the Southern High Plains (SHP) of Texas during two consecutive winter and summer periods, from 1989-91. From 205 mallards, 24,625 helminth individuals were found, representing 35 species (10 trematode, 13 cestode, 10 nematode, and two acanthocephalan species). Prevalences ranged fromItem Influence of crop location, variety and procedure for applying nitrogen fertilizer on the chipping quality of West Texas potatoes(Texas Tech University, 1973-08) Bradley, Rickie DNot AvailableItem Influence of planting date and cotton cultivar on Lygus and fleahopper abundance in the Texas High Plains and the relationship between boll age and Lygus Hesperus damage(Texas Tech University, 2004-08) Cranmer, Andy MarshalNot availableItem Integrated geophysical methods to examine lower crust of southern High Plains(Texas Tech University, 2004-12) Ozyavas, AzizThe high plains of west Texas have a more complex basement structure (Figure 2.7) compared to its flat and featureless surface (Budnik, 1989). The Matador arch, an east-west-trending structural zone that separates the Palo Duro and Midland basins, is a basement-involved faulted and folded belt (Ye et al., 1996). The southern Oklahoma aulacogen that has been described as a failed rift was initiated during Cambrian extension. Subsequently, a wide early Paleozoic basin developed over the initial rift. During the late Paleozoic, fault-bounded basins and uplifts developed in cormection with the Ouachita orogeny, which altered sedimentation patterns. These structures formed a predominantly NW-SE alignment (Coffman et al., 1986). The Amarillo uplift is a narrow basement positive element that trends west-northwest across the Texas Panhandle, to the north of Palo Duro basin. The Anadarko basin trends west-northwest and on its southwest margin is separated from the Wichita-Amarillo uplift by a fault zone with up to 12 km of structural relief (Evans, 1979; Luza et al., 1987). The Permian basin of west Texas is located in the foreland of the late Paleozoic Marathon-Ouachita orogenic belt. The Permain Basin can be characterized as a broken foreland with several prominent, fault-baunded, basement-involved uplifts (Drobek et al., 2002). The gravity profiles suggest that mafic intrusions, uplifts, lower crustal upwarps and shallower layer in the upper mantle are the combined reasons for high gravity anomalies in the region and low gravity anomalies are the combined results of basins, low density rocks of Debaca and Panhandle Terrane, downwarps in the upper mantle layer in conjunction with deeper layer in the upper mantle. The gravity increase in the EW direction in regional scale seems related to a rise in the layer in the upper mantle. The upwaps in the boundary between upper and lower crust are obvious in the north south extending gravity profiles adjacent to the Southern Oklahoma aulacogen might be (?) related to the Late Paleozoic deformation in the foreland of Ouachita orogeny that culminated in Ancestral Rocky mountain orogeny and crustal shortening in the study area. Receiver functions obtained from seismic stations in Lubbock and Albuquerque show that Moho is deep beneath the seismic station of Lubbock around 56 km and crust is around 35 km beneath the seismic station in Albuquerque. Gravity models (A-A', BB', C-C) with a rift pillow pinching out towards High plains and getting smaller towards north make our gravity models consistent with the seismic data. Gravity models without a rift pillow shows that Moho gets deeper beneath the seismic station in Albuquerque and gets shallower towards high plains which does not fit our seismic data.Item Lightning signatures in convective storms on the High Plains(Texas Tech University, 2003-12) Martinez, MaribelAn understanding of the association between storm intensity and lightning activity may help forecasters better distinguish between severe and non-severe storms. Seven storms were analyzed in this study in attempt to better understand lightning behavior relative to storm severity. Six of the cases analyzed produced severe weather. The main distinguishing factor between non-severe and severe storms was a flash rate increase and a radiation spread in the 4 to 10 km regions. Each of the cases produced +CG lightning but more importantly experienced a polarity reversal. In cases where either a tornado warning was issued or an actual tornado was reported, the polarity reversal occurred before all tornadic events. The polarity reversal itself was associated with a decrease in lightning in the mid-levels of the temporal height distributions. Peak currents also increased in strength after the reversal. The study shows that total lightning behavior, although it may vary from region to region, differs in severe and non-severe stages of thunderstorms