Browsing by Subject "Irrigation"
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Item Agroecology of three integrated crop-livestock systems in the Texas High Plains(2012-05) Zilverberg, Cody; Allen, Vivien G.; Johnson, Phillip N.; Galyean, Michael L.; Moore-Kucera, Jennifer; Villalobos, Carlos; Kellison, RickTechnological advances have enabled agriculture to feed and clothe a growing global population with great success. It is now imperative that we remain productive while halting the natural resource degradation that often accompanies high productivity. In the semi-arid Texas High Plains, sustainability of current agricultural practices is threatened by depletion of the Ogallala aquifer and soil erosion. Perennial grasses, the region’s historic vegetation, can build soil rather than lose it and require little or no supplemental irrigation. We designed and tested three agroecosystems that integrated crop and livestock production using a base of perennial forages. All systems were designed to decrease water withdrawals from the Ogallala aquifer relative to conventional irrigated agriculture. The experiment covered a total of 42 ha in a randomized block design with three blocks. The non-irrigated system, DRY (evaluated from 2004 to 2008), included a paddock of native perennial grasses and a rotation of cotton (Cynodon dactylon [L.] Pers.) and foxtail millet (Setaria italica [L.] P. Beauv.). The buffer-irrigated system, LOW (evaluated from 2009 to 2011), was the same as DRY except that LOW added an irrigated paddock of ‘WW-B. Dahl’ old world bluestem (Bothriochloa bladhii [Retz] S.T. Blake; hereafter bluestem), which was harvested for grass seed as well as grazed. The limit-irrigated system, MED (evaluated from 2007 to 2011), included two irrigated paddocks of bermudagrass that were grazed and harvested for hay, and one paddock of bluestem that was grazed and harvested for grass seed. Angus beef stocker steers (Bos taurus L.; initial BW: 245 kg) sequence-grazed each system. We evaluated these systems with a variety of criteria, including forage and animal production, water use, crop yields and quality, forage quality, soil C fractions, soil penetration resistance, forage species stability, economic performance, fossil fuel energy use, and C emissions associated with fossil fuel use. We found that each system had strengths and weaknesses. Annual irrigation water use by each system was: DRY, 0 mm; LOW, 44 mm; and MED, 229 mm. The MED system was the most productive, yielding 446 kg steer live weight gain ha-1, compared with 107 for LOW and 57 for DRY. Bermudagrass yielded the most animal unit grazing days ha-1 (644; bluestem: 246; native grasses: 90; annuals: 41) of any forage and was the highest quality forage with the exception of the annual, foxtail millet. Bermudagrass also had the highest soil concentration of particulate organic matter C (3.1 g kg-1 soil in top 5 cm; native grass: 2.5; bluestem: 2.1), an indicator of higher potential nutrient mineralization and soil C accumulation. The annual fields had the lowest levels (1.3 g kg-1 soil in top 5 cm); however, the MED system was the worst economic performer and emitted the most C (774 kg C ha-1; LOW: 226; DRY: 205) as a consequence of fossil fuel use. In contrast, DRY produced the least amount of grazing (72 animal unit grazing days ha-1; LOW: 76; MED: 434), but was the most profitable and used no irrigation water. Although productivity of DRY and LOW were less than MED, LOW and MED beef carcasses were of equivalent quality (68% USDA Choice; DRY was not evaluated) and cotton lint from DRY and LOW received price premiums in all years (mean $0.024 and 0.106 kg-1, respectively). The lessons learned from this experiment should be used to design future agroecosystems that conserve soil and water while producing agricultural goods. Relative to annual and perennial non-irrigated paddocks, applying irrigation and N to introduced forages increased productivity and accelerated soil C sequestration, but the additional inputs were not justified economically. It may be more profitable to integrate, at the farm or landscape scale, large areas of non-irrigated native grasses in combination with smaller areas of intensively farmed, high-value crops that receive irrigation and fertilizer. Ley farming, which includes long rotations of perennial grass with annual crops, is one option that may hold promise for the future.Item Continuous canopy temperature as a tool for managing deficit irrigation(2012-12) Young, Andrew W.; Dotray, Peter A.; Mahan, James R.; Payton, Paxton R.Deficit irrigation is becoming a trend in agricultural lands with reduced water. With the declining water resources comes renewed interest in deficit irrigation strategies and enhanced management capabilities to provide water when and where it is needed. However, in the past, plant-monitoring capabilities to assess water status of the plant were very costly and labor intensive. The innovation in infrared thermometry systems has allowed for the technology to become smaller and more cost efficient. This investigation uses the established method of BIOTIC developed by research scientist at USDA/ARS. The BIOTIC method has been patented and licensed by a new technology startup company, Smartfield™, under the moniker Smartcrop™. The research conducted used the Smartcrop™ technology, which consists of wireless infrared sensors and base stations for recording data from sensors. This thesis focused on the 2009 and 2010 cotton growing seasons in the Lubbock area. Water and yield data were discussed and analyzed in detail along with other environmental data relevant to plant growth and yield. Analysis and discussion of large temperature data sets were conducted. Canopy temperature comparisons were made using the BIOTIC method along with air vs. canopy temperature comparisons and treatment temperature comparisons. Vapor pressure deficits were also discussed in detail for selected treatments over the growing seasons. Finally, daytime average canopy temperature comparisons provided accurate estimates of water through the plant as a predictor of yield.Item Cotton Lint Yield, Fiber Quality, and Water-Use Efficiency as Influenced by Cultivar and Irrigation Level(2013-05) Cave, Justin; Keeling, Wayne; Dotray, Peter A.; Ritchie, Glen L.; Johnson, JeffCotton is produced in the Texas High Plains under a wide range of water levels, ranging from dryland (rainfed) to full irrigation, with irrigation levels that depend on well capacities. With declining pumping capacities, it is important to maximize water-use efficiency (WUE) through crop management and cultivar selection. The objectives of this research were to 1) evaluate the lint yield and fiber quality of current commercial and experimental cotton cultivars, 2) determine the WUE of these cultivars in different irrigation settings 3) identify the returns above cost for each cultivar within irrigation treatments, and 4) determine which cultivar is best for producers with varying levels of irrigation water and risk preference on the Texas High Plains. Field studies were conducted in 2011 and 2012 to evaluate new cultivars under varying irrigation inputs at Lamesa and Lubbock, TX. The experimental design at both locations was a split plot design with irrigation as the main effect and cultivar as the split effect. Eight cultivars [DP 0912 B2RF, DP 1032 B2RF, DP 1044 B2RF, DP 1212 B2RF, DP 1219 B2RF, 11R110B2R2, 11R112B2R2 (DP 1321 B2RF), and 11R159B2R2 (DP 1359 B2RF)] and four irrigation levels, replicated three times were evaluated in 2011 at Lubbock and Lamesa. Target irrigation levels were 0, 30, 60, and 90% ET replacement. In 2012, twelve cultivars with four replications were evaluated including the eight from 2011. The four additional experimental cultivars included: 11R124B2R2 (DP 1311 B2RF), 11R136B2R2, 11R154B2R2, and 12R242B2R2. Due to the excessive temperatures and drought conditions experienced in 2011, a reduction in yield and fiber quality was seen at both locations. At both locations in both years, increased yields were produced at increased irrigation levels; however, no cultivar by irrigation level interaction was observed. In 2012 at Lamesa, WUE declined as irrigation increased while no differences in WUE between irrigation levels were observed in Lubbock. Over all four trials, no cultivar by irrigation interaction for WUE was observed. Staple length tended to increase as irrigation increased, while the relationship of other fiber quality parameters was less pronounced. Net returns varied among cultivars, and influenced which cultivars were preferred by producers with different risk preferences. In both years at Lubbock, DP 1321 B2RF was the most preferred cultivar for risk averse producers, while DP 1219 B2RF and DP 1359 B2RF were among the most preferred cultivars for risk averse producers in three out of the four trials. In both 2012 locations, 11R136B2R2 had fiber length greater than or equal to all other cultivars.Item Developmental responses of cotton genotypes to varying water application regimes(Texas Tech University, 2004-05) West-Emerson, Cora LeaNot availableItem Ditches across the desert: a story of irrigation along New Mexico's Pecos River(Texas Tech University, 1997-12) Bogener, Stephen Dean; Miller, Catherine; Brink, James E.; Kuethe, Allan J.; Flynn, George Q.; Martinez, CamiloSettlement of the West came slowly, based on advances in technology and the harnessing of nature, especially water. In the arid environment of New Mexico's Pecos Valley, the exploitation of available water resources, combined with corporate accumulation of land through manipulation of federal land laws, led to speculation and development in the frontier region of southeast New Mexico. This dissertation traces that development, beginning in the late 1870s, and examines subsequent events in the Pecos Valley until 1925. First used as open range for cattle grazing, the Pecos Valley became the scene of ever more ambitious plans to establish an agricultural mecca based on irrigation and funded by wealthy investors from Chicago, New York, Colorado Springs, and Europe. Following a natural disaster and financial downturns in 1893, settlers and investors fled the valley, making its future uncertain. A series of financial reorganizations to attract much needed capital brought a major railroad to the valley, but the heyday of corporate irrigation was over.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 Methods for Predicting Seepage Loss Rates for the Hard Lined Irrigation Canals of the Lower Rio Grande Valley of Texas(2014-01-15) Leigh, EricThis project investigated the measured loss rates and observed canal lining conditions by the Texas AgriLife Extension Service to evaluate the Davis-Wilson empirical formula and to further develop a canal condition rating system for predicting loss rates. This research is to help irrigation districts of the Lower Rio Grande Valley of Texas to identify and prioritize the high loss deteriorated lined canals for rehabilitation and management. The ponding test method was used to estimate the loss rates on 32 canal sections. The condition rating scores were evaluated for 26 of these canals. Test calculation revisions and testing errors were first evaluated to understand the potential impacts to the seepage loss rates and condition rating system. The condition rating system had good results for canals with a ranking of 1, predicting losses less than 0.38 (ft^(3)/ft^(2)/day). Canals with rankings of 2 and 3 had a larger range in loss rates. This could be attributed to either the subsoil types having more influence as the lining conditions become more deteriorated or errors in the rating system. The Davis-Wilson empirical formula had poor results at predicting loss rates for the local lining conditions. The seepage loss rates were used to calibrate the formula and derive new coefficients (Cvalues). The C-values were correlated with the scores of the condition rating system (i.e. Ranking 1 = C-values 1-11). Relationships were also found between the canal dimensions, water loss rates, and conditions ratings. In general, larger, deeper canals were in better condition and had lower loss rates. Smaller canals had more variability in both loss rates and condition ratings.Item Investigating Rainwater Harvesting as a Stormwater Best Management Practice and as a Function of Irrigation Water Use(2012-02-14) Shannak, Sa'D Abdel-HalimStormwater runoff has negative impacts on water resources, human health and environment. In this research the effectiveness of Rain Water Harvesting (RWH) systems is examined as a stormwater Best Management Practice (BMP). Time-based, evapotranspiration-based, and soil moisture-based irrigation scheduling methods in conjunction with RWH and a control site without RWH were simulated to determine the effect of RWH as a BMP on a single-family residence scale. The effects of each irrigation scheduling method on minimizing water runoff leaving the plots and potable water input for irrigation were compared. The scenario that reflects urban development was simulated and compared to other RWH-irrigation scheduling systems by a control treatment without a RWH component. Four soil types (sand, sandy loam, loamy sand, silty clay) and four cistern sizes (208L, 416L, 624L, 833L) were evaluated in the urban development scenario. To achieve the purpose of this study; a model was developed to simulate daily water balance for the three treatments. Irrigation volumes and water runoff were compared for four soil types and four cistern sizes. Comparisons between total volumes of water runoff were estimated by utilizing different soil types, while comparisons between total potable water used for irrigation were estimated by utilizing different irrigation scheduling methods. This research showed that both Curve Number method and Mass-Balance method resulted in the greatest volumes of water runoff predicted for Silty Clay soil and the least volumes of water runoff predicted for Sand soil. Moreover, increasing cistern sizes resulted in reducing total water runoff and potable water used for irrigation, although not at a statistically significant level. Control treatment that does not utilize a cistern had the greatest volumes of predicted supplemental water among all soil types utilized, while Soil Moisture-based treatment on average had the least volume of predicted supplemental water.Item Irrigation response in cotton to optimize yield, quality and profitability in the Texas high plains(2009-05) Mathis, Garrett M.; Bednarz, Craig W.; Johnson, Jeff; Boman, Randal K.An imperative issue facing production agriculture on the South Plains is water availability. Over time, water has been drawn out of the Ogallala Aquifer at a rate that exceeds its ability to recharge. Therefore, efficient irrigation levels and seeding rates that optimize cotton quality and yield are vital to this region. A two-year study consisting of one cotton variety, three levels of irrigation and three diverse plant populations was located at two locations in Lubbock County, Texas in 2007 & 2008. Irrigation played a significant role in many yield and fiber quality measurements. The lowest irrigation treatment matured the earliest and produced low yields but had the highest micronaire values. Lint yields were highest for the high irrigation treatment at two of the three locations, but saw decreased fiber quality due to lack of maturity. Seeding rate played a small role in determining yield and fiber quality. Three different weather patterns had varying effects on the results of this study. An economic analysis determined the net return from lint with regard to variable inputs in order to provide profitability comparisons for the producer. The highest net returns from lint ranged from $1,308.34 (Quaker 2007) to $2,851.62 (Quaker 2008). We conclude that weather patterns, coupled with irrigation, heavily impact fiber yield and quality in the Texas High Plains.Item Masters not friends : land, labor and politics of place in rural Pakistan(2013-05) Rizvi, Mubbashir Abbas; Ali, Kamran Asdar, 1961-This dissertation analyzes the cultural significance of land relations and caste/religious identity to understand political subjectivity in Punjab, Pakistan. The ethnography details the vicissitudes of a peasant land rights movement, Anjuman-e Mazarin Punjab (Punjab Tenants Association) that is struggling to retain land rights on vast agricultural farms controlled by the Pakistan army. The dissertation argues that land struggles should not only be understood in tropes of locality, but also as interconnected processes that attend to global and local changes in governance. To emphasize these connections, the dissertation gives a relational understanding of 'politics of place' that attends to a range of practices from the history of colonial infrastructure projects (the building of canals, roads and model villages) that transformed this agricultural frontier into the heart of British colonial administration. Similarly, the ethnographic chapters relate the history of 'place making' to the present day uncertainty for small tenant sharecroppers who defied the Pakistan Army's attempts to change land relations in the military farms. Within these parameters, this ethnographic study offers a "thick description" of Punjab Tenants Association to analyze the internal shifts in loyalties and alignments during the course of the protest movement by looking at how caste, religious and/or class relations gain or lose significance in the process. My research seeks to counter the predominant understanding of Muslim political subjectivity, which privileges religious beliefs over social practices and regional identity. Another aspect of my work elucidates the symbolic exchange between the infrastructural project of irrigation, railway construction and regional modernity in central Punjab. The network of canals, roads and railways transformed the semi-arid region of Indus Plains and created a unique relationship between the state and rural society in central Punjab. However, this close relationship between rural Punjab and state administration is not void of conflict but rather it indicates a complex sense of attachment and alienation, inclusion and exclusion from the state.Item Mechanism of drought tolerance in cotton-response of cotton cultivars to irrigation in the Texas High Plains(2011-05) Poudel, Esha; Thompson, Thomas L.; Bednarz, Craig W.; Holaday, A. ScottMechanism of Drought Tolerance in Cotton- Response of Cotton cultivars to Irrigation in the Texas High Plains (2011) Esha Poudel Chair of Advisory Committee: Dr. T.L.Thompson Cotton is the most profitable crop produced in the Texas High Plains but water deficiency is a crucial factor affecting both the yield and fiber quality in the region. Increasing cotton tolerance to water stress will be of even greater importance in the future. We tested the hypothesis that different cotton phenotypes, with okra and normal-leaf morphology, will have similar values for physiological responses related to water stress, such as, stomatal conductance, photosynthetic rate, vapor pressure deficit levels, internal CO2 concentration, and transpiration rate, under varying water availability and that these responses will similarly related to yield. A two year field study was conducted to determine the effects and interactions of irrigation amounts and cultivars on yield and quality of cotton and analyze and identify the physiological traits associated with drought tolerance in Lubbock County, Texas in 2008 and 2009. The experiment consisted of three irrigation amounts and two cultivars in each year. An important objective of the study was to see whether the yield and fiber quality will be independent of the phenotypes and the irrigation treatments. In both the years the yield was significantly different between the phenotypically different cultivars. Yields were also not independent of the irrigation in 2009. Fiber quality parameters showed varying response to irrigation amounts in both years. Stomatal conductance, photosynthetic rate and the internal CO2 concentration increased with increase in irrigation in 2009. The normal leaf phenotype was more responsive to irrigation than the okra leaf cultivar and also achieved higher yield. In both cultivars, stomatal conductance and photosynthesis were positively correlated with water availability. As expected, vapor pressure deficit was negatively correlated with water availability. Because the normal leaf cultivar was more responsive to water availability we reject our hypothesis.Item Optimal economic combination of irrigation technology and cotton varieties on the High Plains of Texas(2008-05) Wilde, Curtis; Johnson, Jeff; Johnson, Phillip N.; Keeling, WayneCotton is the leading agricultural crop in the Texas High Plains. Cotton producers have experienced steady to declining cotton prices coupled with increasing input costs resulting in tightening profit margins. Many new and improved technologies including varieties and irrigations systems are being developed and used in production agriculture. Producers are adopting these new technologies; however, they need information on the proper management of these technologies to help maximize their returns and insure their continued profitability. Therefore, the objectives of this research were to determine the farm-level economic impact of the adoption of subsurface irrigation vs. center pivot irrigation, determine the farm level economic impact of the adoption of new, higher yielding and higher quality varieties, and determine the optimal combinations of applied irrigation water and variety selection for irrigated cotton farms on the Texas High Plains. Cotton yield and quality data collected from irrigation studies under different technologies and variety selection at the AG-CARES research farm at Lamesa, TX and the Helms research farm at Halfway, TX will be evaluated to meet these objectives. Gross margins and net returns above total variable and fixed irrigation costs were estimated for varieties and irrigation systems with different irrigation levels. The results obtained from this analysis showed that producers could increase gross margins by adopting new varieties. In addition, estimations showed that Sub Surface Drip Irrigation can produce higher net returns than Low Energy Precision Application center pivot systems. Estimations from two locations demonstrate the importance of managing production according to environmental factors. Top performing varieties differed between locations along with optimal irrigation levels. This analysis emphasizes the importance for cotton producers to be informed and properly manage their production.Item Solar-thermal jet pumping for irrigation(Texas Tech University, 1980-05) Dellenback, Paul A.Not availableItem Spatial and temporal relationships between center pivot irrigation and groundwater resources on the Texas Southern High Plains(2012-05) Van-Nice, Chris; Mulligan, Kevin; Rainwater, Ken; Fish, Ernest B.; Lee, JeffreyThe purpose of this study is to investigate the geography of center pivot agriculture on the Texas Southern High Plains. The main goal is to better understand the spatial and temporal relationships between center pivot agriculture and groundwater resources in West Texas. Specifically this study addresses three research questions. 1) Has there been an increase in center pivot fields over time? 2) Is there a strong spatial relationship between center pivot fields and the saturated thickness of the aquifer? 3) Is there a strong spatial relationship between center pivot fields and the rates of aquifer depletion? Results from this research showed an increase in center pivot fields between 1995 and 2004, resulting in an increase in center pivot acreage in the region. The results from this study also support the idea that once the saturated thickness of the aquifer reaches 30 feet or less, it becomes difficult to support production level irrigated agriculture. The results from the aquifer depletion analysis showed a strong inverse relationship; as the center pivot acreage increased, the saturated thickness of the aquifer decreased in most cases.Item The Effect of Irrigation Methods and Levels on Several Crops(Texas Tech University, 1973-05) Garrett, J. LegettNot Available.Item Utilization of nitrogen from surface and subsurface applied wastewater(2012-12) Francis, Richard; Fedler, Clifford B.; Jackson, Andrew W.; Zartman, Richard E.A pilot test was conducted to determine the difference in nitrogen removal between surface and subsurface applied wastewater systems in soil columns topped with Bermuda grass (cynodon dactylon). Six columns were set up, three with water applied to the surface, and three with water applied in the subsurface through a positive-displacement pump. The concentration of nitrogen was kept uniform within the system with variable loading rates to ensure leaching occurred. The water added and the water leached were tested with HACH(R) test-n-tube kits for total nitrogen, ammonia, and nitrate-N concentrations. A statistical analysis was performed to determine if there were any significant differences in the concentrations of these constituents in the effluents between the two systems. The analysis showed that there was virtually no difference (Pr>F = 0.657) between the two systems in regards to percent of nitrogen removed from the system. The test also showed that subsurface applied systems performed marginally better that surface applied systems in total nitrogen and nitrate-N concentrations in the effluent. There were also virtually no differences (Pr>F = 0.209) in the total Kjeldahl Nitrogen concentrations in the plant tissue.Item Water conservation on campuses of higher education in Texas(2014-08) Zellner, Hannah Marie; Pierce, Suzanne Alise, 1969-Facing drought and water shortages, many regions of the United States and the world have been forced to improve water resources management. In water-stressed areas of the US, water conservation has become the most economically viable water supply option available. As such, water conservation efforts are an increasingly popular method of demand management and have proven effective at various scales throughout the country. Many states in the arid southwest, including Texas, have incorporated water conservation strategies into their state water plans to reduce demand during drought conditions. At the 2013 Summit for the Texas Regional Alliance for Campus Sustainability (TRACS), water conservation was identified as a critical issue for higher education institutes (HEI) across the state. HEIs are analogous to small cities in terms of their resource use, and can also serve as test labs for sustainability concepts and resource management strategies. In response to concerns about water scarcity, TRACS launched an evaluation of water conservation strategies across Texas’ HEI campuses. The project collected data focused on the use of water conservation methods and their perceived effectiveness in irrigation and landscaping, building use, and utilities. Additionally, water conservation educational efforts, and the goals and policies of HEIs were considered. The objectives of the project were to collaborate with Texas HEIs, compile a database of best practices, and identify regional preferences in a state with varying climates and water resources. The results of the survey determined that native and adaptive plants were the most-widely used water conservation method for irrigation and landscaping as well the most effective strategy. In buildings, low-flow plumbing was reported to be the most widely-used and also most effective water conservation method. A variety of water conservation measures were used in utilities; metering, maintenance, and recycling water were viewed as most effective. While many HEIs reported offering opportunities for students to learn or participate in research about water conservation, only half reported offering workshops or courses for managerial staff and faculty. Education for staff and faculty is a particularly important area for improvement, as many staff members are closely involved in managing water use across campuses. Many of the HEIs reported having water conservation policies in place or pending and some participating HEIs reported having target reduction plans and involvement with agencies related to water conservation. It is important for the administration of educational institutions to put policies and plans in place to guide the everyday operations of a campus. HEIs in the state are making great strides in water conservation, but establishing a network to share best practices and improvements could significantly enhance campus water conservation initiatives.