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| Registros recuperados: 36 | |
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| King, B.A.. |
| Numerous moving spray-plate center-pivot sprinklers are commercially available providing a range of drop size distributions and wetted diameters. A means to quantitatively compare sprinkler choices in regards to maximizing infiltration and minimizing runoff is currently lacking. The objective of this study was to develop a soil independent quantitative runoff potential index to facilitate selection of sprinklers for center-pivot sprinkler irrigation systems. Drop sizes, velocities and water application rates of numerous moving spray-plate sprinklers were measured in the laboratory over a range of flow rates and operating pressures. The proposed sprinkler runoff index is based on application rates of kinetic energy and water computed by overlapping specific... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation; Infiltration; Center pivot. |
| Ano: 2016 |
URL: http://eprints.nwisrl.ars.usda.gov/1612/1/1569.pdf |
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| King, B.A.; Bjorneberg, D.L.. |
| The kinetic energy of discrete water drops impacting a bare soil surface generally leads to a drastic reduction in water infiltration rate due to formation of a seal on the soil surface. Under center-pivot sprinkler irrigation, kinetic energy transferred to the soil prior to crop canopy development can have a substantial effect on seasonal runoff and soil erosion, especially when the soil is not protected by crop residue cover. Droplet kinetic energy of seven commercial off-center action rotating spray-plate sprinklers was characterized over a range of flow rates and pressures. Sprinkler droplet kinetic energy was characterized using two methods; droplet kinetic energy per unit sprinkler discharge and droplet kinetic energy applied per unit water depth... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation; Center pivot. |
| Ano: 2012 |
URL: http://eprints.nwisrl.ars.usda.gov/1457/1/1422.pdf |
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| Tarkalson, D.D.; Eujayl, Imad A.; King, B.A.. |
| Technical Abstract: Increased water demands and drought have resulted in a need to indentify crop hybrids that are drought tolerant, requiring less irrigation to sustain yields. This study was conducted to assess differences in drought tolerance among a group of genetically diverse sugarbeet hybrids. The study was conducted over three consecutive growing seasons (2008-2010) at the USDA Northwest Irrigation and Soils Research Laboratory in Kimberly, ID on a Portneuf silt loam soil (coarse-silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid). Drought tolerance was evaluated by measuring sucrose yield production of six experimental hybrids of KWS SAAT AG and one commercial hybrid (Betaseed Inc.) under six water input treatments. Hybrid drought... |
| Tipo: Article |
Palavras-chave: Sugarbeet. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1553/1/1509.pdf |
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| King, B.A.; Winward, T.W.; Bjorneberg, D.L.. |
| Kinetic energy of water droplets has a substantial effect on development of a soil surface seal and infiltration rate of bare soil. Methods for measuring sprinkler droplet size and velocity needed to calculate droplet kinetic energy have been developed and tested over the past 50 years, each with advantages, disadvantages, and limitations. Drop size and velocity of an impact sprinkler at three operating pressures and one nozzle size were measured using a laser precipitation meter and compared with published values obtained using a photographic method. Significant differences in cumulative volume drop size distributions derived from the two measurement methods were found, especially at the highest operating pressure. Significant differences in droplet... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation. |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1543/1/1500.pdf |
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| King, B.A.; Bjorneberg, D.L.; Trout, T.J.; Mateos, L; Araujo, D. F.; Costa, R. N.. |
| The area irrigated by furrow irrigation in the U.S. has been steadily decreasing but still represents about 20% of the total irrigated area in the U.S. Furrow irrigation sediment loss is a major water quality issue and a method for estimating sediment loss is needed to quantify the environmental impacts and estimate effectiveness and economic value of conservation practices. Artificial neural network (NN) modeling was applied to furrow irrigation to predict sediment loss as a function of hydraulic and soil conditions. A data set consisting of 1926 furrow evaluations spanning three continents and a wide range of hydraulic and soil conditions was used to train and test a multilayer perceptron feed forward NN model. The final NN model consisted of 16 inputs,... |
| Tipo: Article |
Palavras-chave: Furrow irrigation; Water quality. |
| Ano: 2015 |
URL: http://eprints.nwisrl.ars.usda.gov/1593/1/1551.pdf |
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| King, B.A.; Tarkalson, D.D.; Bjorneberg, D.L.; Taberna, J.P, Jr.. |
| Conversion of potato ridged-row planting systems to wide bed planting systems may increase water and nitrogen use efficiency in commercial irrigated potato production systems by reducing the amount of irrigation water and water applied nitrogen fertilizer bypassing the potato root zone. Wide bed planting systems consist of planting multiple rows on a wide bed with 20 to 35% higher plant population than found in conventional ridgedrow planting systems. The objective of this study was to evaluate the effect planting system has on yield response of ‘Russet Norkotah’ potato to irrigation and nitrogen. Planting systems evaluated were (1) conventional ridgedrow with dammer-diking; (2) 3.7 m wide bed with five potato rows spaced 66 cm between adjacent rows... |
| Tipo: Article |
Palavras-chave: Practical farm efficiency; Sprinkler irrigation; Potato; Nitrogen. |
| Ano: 2011 |
URL: http://eprints.nwisrl.ars.usda.gov/1425/1/1395.pdf |
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| King, B.A.; Winward, T.W.; Bjorneberg, D.L.; Wall, R.W.. |
| Peak water application rate in relation to soil water infiltration rate and soil surface storage capacity is important in the design of center pivot sprinkler irrigation systems for efficient irrigation and soil erosion control. Measurement of application rates of center pivot irrigation systems has traditionally used tipping bucket rain gauges. Calculation of application rate from tipping bucket rain gauge measurements restricts computed application rate to a discrete multiple of the rain gauge resolution and time interval. This limits the resolution of application rate measurement, especially for time intervals less than 15 minutes. A collector was designed to measure time variant high intensity sprinkler application rates under field conditions with... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation; Soil; Water. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1565/1/1521.pdf |
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| King, B.A.; Bjorneberg, D.L.. |
| The kinetic energy of discrete drops impacting a bare soil surface is generally observed to lead to a drastic reduction in water infiltration rate due to soil surface seal formation. Under center pivot sprinkler irrigation, kinetic energy transferred to the soil prior to crop canopy development can have a substantial effect on seasonal runoff and soil erosion. In the design of center pivot irrigation systems, selection of sprinklers with minimum applied kinetic energy could potentially minimize seasonal runoff and erosion hazard. Size and velocity of drops from five common center pivot sprinklers with flow rates of approximately 43 L/min were measured using a laser in the laboratory. The data were used to evaluate various approaches to characterize... |
| Tipo: Article |
Palavras-chave: Irrigation control; Sprinkler irrigation; Center pivot. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1566/1/1522.pdf |
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| King, B.A.; Dungan, R.S.; Bjorneberg, D.L.. |
| Wind drift and evaporation losses (WDELs) are an often discussed topic in regards to center pivot sprinkler irrigation efficiency. Opinions on the magnitude of WDELs vary widely, in part due to the wide variation in WDEL values published in the literature. The magnitude of WDELs reported in the literature range from 2 to 45%. The common technique employed to measure WDEL is to use catch cans and compare the measured volume of catch with the volume of water applied based on sprinkler nozzle size, operating pressure and spacing with the difference being WDEL. The inaccuracies of catch cans resulting from wind effects on catch efficiency and evaporation of water from the catch can prior to measurement have led to the wide range in WDEL reported in the... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation; Center pivot. |
| Ano: 2012 |
URL: http://eprints.nwisrl.ars.usda.gov/1470/1/1435.pdf |
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| King, B.A.; Bjorneberg, D.L.. |
| The marked reduction in infiltration rate caused by formation of a soil surface seal due to water droplet impact on bare soil is a well known phenomenon but is rarely considered in infiltration models, especially under center pivot irrigation. The objective of this study was to develop a soil infiltration model for center pivot sprinkler irrigation that incorporates the transient reduction in soil surface seal hydraulic conductivity as affected by soil and sprinkler characteristics. A sealing soil infiltration model was developed using an explicit finite difference solution scheme with a transient soil seal formation model, which is unique from other studies in that it explicitly uses droplet specific power as the driving factor for formation of a soil... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation; Infiltration; Center pivot. |
| Ano: 2012 |
URL: http://eprints.nwisrl.ars.usda.gov/1469/1/1434.pdf |
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| King, B.A.; Shellie, Krista. |
| Precision irrigation management in wine grape production is hindered by the lack of a reliable method to easily quantify and monitor vine water status. Mild to moderate water stress is desirable in wine grape for controlling vine vigor and optimizing fruit yield and quality. A crop water stress index (CWSI) that effectively monitors plant water status has not been widely adopted in wine grape because of the need to measure well-watered and non-transpiring leaf temperature under identical environmental conditions. In this study, we calculated a daily CWSI for the wine grape cultivars Syrah and Malbec (Vitis vinifera L.) by estimating well-watered leaf temperature with an artificial neural network (NN) model and non-transpiring leaf temperature based on the... |
| Tipo: Article |
Palavras-chave: Water management. |
| Ano: 2016 |
URL: http://eprints.nwisrl.ars.usda.gov/1611/1/1568.pdf |
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| King, B.A.; Taberna, J.P, Jr.. |
| Fumigation for nematode management in irrigated potato production systems of Idaho is widely practiced. Spatially uniform fumigation with large scale soil injection equipment is the only labeled application method for 1,3-dichloropropene. Plant-parasitic nematode species exhibit spatially variable population densities that provide an opportunity to practice site-specific fumigation to reduce chemical usage and production costs. During 2002-2008, 62 fields intended for commercial potato production in eastern Idaho were sampled using a geo-referenced grid sampling system for plant-parasitic nematode population densities. In total, 4,030 grid samples were collected representing nearly 3200 ha of commercial potato production. Collectively, 73% of the grid... |
| Tipo: Article |
Palavras-chave: Potato. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1534/1/1491.pdf |
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| Bjorneberg, D.L.; King, B.A.. |
| Dairy production has expanded in irrigated areas of the western and southwestern US, potentially competing for limited water supplies. Groundwater withdrawal was measured for two years on six dairy farms with 660 to 6400 milk cows in southern Idaho. Groundwater withdrawal was calculated on an equivalent cow basis to account for relative differences in the numbers of milk cows, dry cows, heifers and calves on each farm. Average groundwater withdrawal from each dairy varied from 110 to 250 L/d/eq. cow with an overall average of 190 L/d/eq. cow for the six farms. On an area basis, groundwater withdrawal varied from 180 to 880 mm/y on each farm with a mean of 530 mm/y. Estimated annual irrigation requirements in southern Idaho are 510 mm for spring barley, 590... |
| Tipo: Article |
Palavras-chave: Animal; Water management. |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1531/1/1489.pdf |
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| King, B.A.; Shellie, Krista. |
| Mild to moderate water stress is desirable in wine grape for controlling vine vigor and optimizing fruit yield and quality, but precision irrigation management is hindered by the lack of a reliable method to easily quantify and monitor vine water status. The crop water stress index (CWSI) that effectively monitors plant water status has not been widely adopted in wine grape because of the need to measure well-watered and non-transpiring leaf temperature under identical environmental conditions. In this study, a daily CWSI for the wine grape cultivar Syrah was calculated by estimating well-watered leaf temperature with an artificial neural network (NN) model and non-transpiring leaf temperature based on the cumulative probability of the measured difference... |
| Tipo: Conference or Workshop Item |
Palavras-chave: Irrigation control; Water. |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1582/1/1538.pdf |
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| Registros recuperados: 36 | |
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