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• 541. [Image] Secteur test de Litanieh (Qasmieh) Plan du reseau D'irrigation Existant

  	Citation × Citation Citation Abstract Copy Title: Secteur test de Litanieh (Qasmieh) Plan du reseau D'irrigation Existant Year: 2008 Title: Secteur test de Litanieh (Qasmieh) Plan du reseau D'irrigation Existant Year: 2008 Close

• 542. [Image] Monde-Arabe Maghreb-Machrek La question de l'eau au Moyen-Orient: Discours et r alit s

  	Citation × Citation Citation Abstract Copy Title: Monde-Arabe Maghreb-Machrek La question de l'eau au Moyen-Orient: Discours et r alit s Author: Shuval, Hillel I., 1926- Year: 2008 Title: Monde-Arabe Maghreb-Machrek La question de l'eau au Moyen-Orient: Discours et r alit s Author: Shuval, Hillel I., 1926- Year: 2008 Close

• 543. [Article] Improving soil water determination in spatially variable field using fiber optic technology and Bayesian decision theory

  Achieving and maintaining sustainability in irrigated agriculture production in the era of rapidly increasing stress on our natural resources require, among other essential actions, optimum control and ...

  Citation × Citation Citation Abstract Copy Title: Improving soil water determination in spatially variable field using fiber optic technology and Bayesian decision theory Author: Sayde, Chadi Achieving and maintaining sustainability in irrigated agriculture production in the era of rapidly increasing stress on our natural resources require, among other essential actions, optimum control and management of the applied water. Thus, a significant upgrade of the currently available soil water monitoring technologies is needed. The primary goal of this work was to reduce the uncertainties of spatially variable soil water in the field. Two approaches are suggested: 1) The Bayesian decision model that implicitly accounts for spatial variability at minimal cost based on limited field data, and 2) The Actively Heated Fiber Optic (AHFO) method that explicitly accounts for spatial variability with high sampling density at relatively low cost per measurement point. The Bayesian decision model uses an algorithm to integrate information embodied in independent estimates of soil water depletion to derive a posterior estimation of soil water status that has the potential to reduce the risk of costly errors in irrigation scheduling decisions. The sources of information are obtained from an ET based water balance model, soil water measurements, and expert opinion. The algorithm was tested in a numerical example based on a field experiment where soil water depletion measurements were made at 43 sites in an agricultural field under center pivot irrigation. The results showed that the estimates of the average soil water depletion in the field obtained from the posterior distributions of soil water depletion proved to outperform simple averaging of n soil water depletion measurements, up to n = 35 measurements. For n< 3, the model also provided a 39% average reduction in risk of error derived from non-representative measurements. The AHFO method observes the heating and cooling of a buried fiber optic (FO) cable through the course of a pulse application of energy as monitored by a distributed temperature sensing (DTS) system to reveal soil water content simultaneously at sub-meter scale along the FO cable that can potentially exceeds kilometers in length. A new and simple interpretation of heat data that takes advantage of the characteristics of FO temperature measurements is presented. The results demonstrate the feasibility of AHFO method application to obtain <0.05 m³m⁻³ error distributed measurements of soil water content under laboratory controlled conditions. The AHFO method was then tested under field conditions using 750 m of FO cables buried at 30, 60, and 90 cm depths in agricultural field. The calibration curve relating soil water content to the thermal response of the soil to a heat pulse was developed in the lab. It was successively applied to the 30 and 60 cm depths cables, while the 90 cm depth cable illustrated the challenges of soil heterogeneity for this technique. The method was used to map with high spatial (1m) and temporal (1hr) resolution the spatial variability of soil water content and fluxes induced by the non-uniformity of water application at the surface. Title: Improving soil water determination in spatially variable field using fiber optic technology and Bayesian decision theory Author: Sayde, Chadi Achieving and maintaining sustainability in irrigated agriculture production in the era of rapidly increasing stress on our natural resources require, among other essential actions, optimum control and management of the applied water. Thus, a significant upgrade of the currently available soil water monitoring technologies is needed. The primary goal of this work was to reduce the uncertainties of spatially variable soil water in the field. Two approaches are suggested: 1) The Bayesian decision model that implicitly accounts for spatial variability at minimal cost based on limited field data, and 2) The Actively Heated Fiber Optic (AHFO) method that explicitly accounts for spatial variability with high sampling density at relatively low cost per measurement point. The Bayesian decision model uses an algorithm to integrate information embodied in independent estimates of soil water depletion to derive a posterior estimation of soil water status that has the potential to reduce the risk of costly errors in irrigation scheduling decisions. The sources of information are obtained from an ET based water balance model, soil water measurements, and expert opinion. The algorithm was tested in a numerical example based on a field experiment where soil water depletion measurements were made at 43 sites in an agricultural field under center pivot irrigation. The results showed that the estimates of the average soil water depletion in the field obtained from the posterior distributions of soil water depletion proved to outperform simple averaging of n soil water depletion measurements, up to n = 35 measurements. For n< 3, the model also provided a 39% average reduction in risk of error derived from non-representative measurements. The AHFO method observes the heating and cooling of a buried fiber optic (FO) cable through the course of a pulse application of energy as monitored by a distributed temperature sensing (DTS) system to reveal soil water content simultaneously at sub-meter scale along the FO cable that can potentially exceeds kilometers in length. A new and simple interpretation of heat data that takes advantage of the characteristics of FO temperature measurements is presented. The results demonstrate the feasibility of AHFO method application to obtain <0.05 m³m⁻³ error distributed measurements of soil water content under laboratory controlled conditions. The AHFO method was then tested under field conditions using 750 m of FO cables buried at 30, 60, and 90 cm depths in agricultural field. The calibration curve relating soil water content to the thermal response of the soil to a heat pulse was developed in the lab. It was successively applied to the 30 and 60 cm depths cables, while the 90 cm depth cable illustrated the challenges of soil heterogeneity for this technique. The method was used to map with high spatial (1m) and temporal (1hr) resolution the spatial variability of soil water content and fluxes induced by the non-uniformity of water application at the surface. Close

• 544. [Article] Monitoring of Soil Moisture: Methods, Improving Wine Quality and Extent of Wetting

  Interim Progress Report to the Wine Advisory Board, Agricultural Research Foundation, and Participating Growers

  Citation × Citation Citation Abstract Copy Title: Monitoring of Soil Moisture: Methods, Improving Wine Quality and Extent of Wetting Author: Rojas, Wilson, Selker, John, Candolfi-Vasconcelos, M. Carmo Interim Progress Report to the Wine Advisory Board, Agricultural Research Foundation, and Participating Growers Title: Monitoring of Soil Moisture: Methods, Improving Wine Quality and Extent of Wetting Author: Rojas, Wilson, Selker, John, Candolfi-Vasconcelos, M. Carmo Interim Progress Report to the Wine Advisory Board, Agricultural Research Foundation, and Participating Growers Close

• 545. [Article] Effect of irrigation level, insecticide and variety on root rot and yield of sweet corn: Research report to the Agricultural Research Foundation and the Oregon Processed Vegetable Commission, 2005

  Summary Irrigation effects on root rot and yield  Reducing irrigation during the first 6 weeks after planting reduced root rot of sweet corn at midseason and at harvest, consistent with findings of the ...

  Citation × Citation Citation Abstract Copy Title: Effect of irrigation level, insecticide and variety on root rot and yield of sweet corn: Research report to the Agricultural Research Foundation and the Oregon Processed Vegetable Commission, 2005 Author: Peachey, Ed Summary Irrigation effects on root rot and yield  Reducing irrigation during the first 6 weeks after planting reduced root rot of sweet corn at midseason and at harvest, consistent with findings of the past two years.  Reducing the early season irrigation level increased yield of Jubilee by 20% because of an increase in the number and size of ears produced. Insecticide effects  Vapam reduced midseason radicle root rot slightly.  The number of insect bites declined as the number of insecticides applied increased.  Insecticides had no effect on root rot at the Vegetable Research Farm, the site with greatest root rot levels. Insecticides may have increased root rot ratings at the Botany farm.  There was a positive but weak correlation (R=0.57) between insect damage to Jubilee roots and nodal root rot at the Vegetable Research Farm.  Insecticides may have increased yield of Coho (at both irrigation levels) and Jubilee (at the Low irrigation level) at the Vegetable Research Farm. Insecticides increased yield of all varieties in the Botany Farm experiment. Varietal effects  Yield of Coho was greater than Jubilee, Kokanee, and Chase at both sites. Coho yields were consistently High under stresses of root rot and insect damage. Title: Effect of irrigation level, insecticide and variety on root rot and yield of sweet corn: Research report to the Agricultural Research Foundation and the Oregon Processed Vegetable Commission, 2005 Author: Peachey, Ed Summary Irrigation effects on root rot and yield  Reducing irrigation during the first 6 weeks after planting reduced root rot of sweet corn at midseason and at harvest, consistent with findings of the past two years.  Reducing the early season irrigation level increased yield of Jubilee by 20% because of an increase in the number and size of ears produced. Insecticide effects  Vapam reduced midseason radicle root rot slightly.  The number of insect bites declined as the number of insecticides applied increased.  Insecticides had no effect on root rot at the Vegetable Research Farm, the site with greatest root rot levels. Insecticides may have increased root rot ratings at the Botany farm.  There was a positive but weak correlation (R=0.57) between insect damage to Jubilee roots and nodal root rot at the Vegetable Research Farm.  Insecticides may have increased yield of Coho (at both irrigation levels) and Jubilee (at the Low irrigation level) at the Vegetable Research Farm. Insecticides increased yield of all varieties in the Botany Farm experiment. Varietal effects  Yield of Coho was greater than Jubilee, Kokanee, and Chase at both sites. Coho yields were consistently High under stresses of root rot and insect damage. Close

• 546. [Image] PH036_1346 Lee Moorhouse photographs

  	The left side of the image is a large open plain that is covered by sand and sagebrush, with no visible trees or other vegetation. The right side of the image has a farmhouse and a barn. The ground around ...
  	Citation × Citation Citation Abstract Copy Title: PH036_1346 Lee Moorhouse photographs Year: 1907 The left side of the image is a large open plain that is covered by sand and sagebrush, with no visible trees or other vegetation. The right side of the image has a farmhouse and a barn. The ground around and beyond the farmhouse is darker in color from the soil content and access to water. In the foreground is a small wooden dam. The sides of the dam are up against a low-tiered wall of sand and rock, built into the embankment. Beyond the embankment, the pathway of the canal from the dam is visible as a dividing line between the the sagebrush area and the farmland area. The canal is identified as the Hinkle irrigation canal, located near Pendleton, Oregon. The house and barn are both constructed of wood. The barn is larger and in front of the house. Only the chimney and part of the roof and one side of the house are visible. There is a fence enclosing the buildings and part of the canal. There is a small white tent or cloth cover to the far right of the buildings. There are some other small structures and farm-related objects near the barn, but not clearly seen. Title: PH036_1346 Lee Moorhouse photographs Year: 1907 The left side of the image is a large open plain that is covered by sand and sagebrush, with no visible trees or other vegetation. The right side of the image has a farmhouse and a barn. The ground around and beyond the farmhouse is darker in color from the soil content and access to water. In the foreground is a small wooden dam. The sides of the dam are up against a low-tiered wall of sand and rock, built into the embankment. Beyond the embankment, the pathway of the canal from the dam is visible as a dividing line between the the sagebrush area and the farmland area. The canal is identified as the Hinkle irrigation canal, located near Pendleton, Oregon. The house and barn are both constructed of wood. The barn is larger and in front of the house. Only the chimney and part of the roof and one side of the house are visible. There is a fence enclosing the buildings and part of the canal. There is a small white tent or cloth cover to the far right of the buildings. There are some other small structures and farm-related objects near the barn, but not clearly seen. Close

• 547. [Article] Soil Water Tension Irrigation Criteria Affects Both Stevia Rebaudiana Leaf Yield and Leaf Steviol Glycoside Composition

  Stevia (Stevia rebaudiana) is a perennial herbaceous plant native to Paraguay and used traditionally by the native Guarani peoples for centuries to sweeten medicinal teas. Stevia has only been commercially ...

  Citation × Citation Citation Abstract Copy Title: Soil Water Tension Irrigation Criteria Affects Both Stevia Rebaudiana Leaf Yield and Leaf Steviol Glycoside Composition Author: Parris, Cheryl A. Stevia (Stevia rebaudiana) is a perennial herbaceous plant native to Paraguay and used traditionally by the native Guarani peoples for centuries to sweeten medicinal teas. Stevia has only been commercially cultivated over the past 50 years and cultural practice information suitable for implementation by growers is limited. Currently stevia’s commercial value is found in its steviol glycoside content, especially rebaudioside A. Growers seek information to maximize productivity of rebaudioside A through improved cultural practices. Irrigation management is one of several important agronomic techniques growers can use to obtain maximum yield while also pursuing water use efficiency. The current trial investigated the effect that soil water tension as an irrigation onset criteria had on stevia dry leaf yields, steviol glycoside content and yield, and steviol glycoside ratios. The experiment was conducted in a field of Owyhee silt loam (coarse-silty, mixed, mesic Xerollic Camborthid) at the Oregon State University, Malheur Experiment Station, Ontario, Oregon, N 43° 58' 53.273'' W 117° 1' 26.396''. Two stevia varieties, SW109 and SW129 (S&W Seed Company Inc., Fresno, California), were subjected to soil water tension irrigation criteria of 10, 20, 40, 60, 80, kPa over a 57-day trial period. Harvested plant material was measured for dry leaf yield and several steviol glycosides. Analysis of variance showed significant variety differences in leaf yield, leaf stevioside and rebaudioside A content and yield, and steviol glycoside ratios (P=0.05). Examining the data by analysis of variance, dry leaf yield, stevioside%, rebaudioside C %, total steviol glycoside (TSG), rebaudioside C yield, and TSG % yield had significant higher results among the wetter compared to the drier soil water tension criteria treatments, yet a preferred treatment regime was not was not clearly evident. When comparing varieties by regression analysis, results showed a highly significant decrease in stevioside % content, and an increase in the ratio of rebaudioside A to stevioside from drier to wetter irrigation onset criteria, whereas, rebaudioside A % content did not show any significant trend at differing irrigation criteria. The results indicate that maximizing dry leaf productivity directly affects the total rebaudioside A yield, which in turn can provide increased crop value to the grower. Irrigating near 10kPa produced higher dry leaf yield and total rebaudioside A yield, than irrigation at drier criteria. Irrigating stevia at 10 kPa at full canopy, the crop coefficient, k[subscript c], was equivalent to 0.97 ET₀, averaging 6.4 mm·d⁻¹ for the days measured. Title: Soil Water Tension Irrigation Criteria Affects Both Stevia Rebaudiana Leaf Yield and Leaf Steviol Glycoside Composition Author: Parris, Cheryl A. Stevia (Stevia rebaudiana) is a perennial herbaceous plant native to Paraguay and used traditionally by the native Guarani peoples for centuries to sweeten medicinal teas. Stevia has only been commercially cultivated over the past 50 years and cultural practice information suitable for implementation by growers is limited. Currently stevia’s commercial value is found in its steviol glycoside content, especially rebaudioside A. Growers seek information to maximize productivity of rebaudioside A through improved cultural practices. Irrigation management is one of several important agronomic techniques growers can use to obtain maximum yield while also pursuing water use efficiency. The current trial investigated the effect that soil water tension as an irrigation onset criteria had on stevia dry leaf yields, steviol glycoside content and yield, and steviol glycoside ratios. The experiment was conducted in a field of Owyhee silt loam (coarse-silty, mixed, mesic Xerollic Camborthid) at the Oregon State University, Malheur Experiment Station, Ontario, Oregon, N 43° 58' 53.273'' W 117° 1' 26.396''. Two stevia varieties, SW109 and SW129 (S&W Seed Company Inc., Fresno, California), were subjected to soil water tension irrigation criteria of 10, 20, 40, 60, 80, kPa over a 57-day trial period. Harvested plant material was measured for dry leaf yield and several steviol glycosides. Analysis of variance showed significant variety differences in leaf yield, leaf stevioside and rebaudioside A content and yield, and steviol glycoside ratios (P=0.05). Examining the data by analysis of variance, dry leaf yield, stevioside%, rebaudioside C %, total steviol glycoside (TSG), rebaudioside C yield, and TSG % yield had significant higher results among the wetter compared to the drier soil water tension criteria treatments, yet a preferred treatment regime was not was not clearly evident. When comparing varieties by regression analysis, results showed a highly significant decrease in stevioside % content, and an increase in the ratio of rebaudioside A to stevioside from drier to wetter irrigation onset criteria, whereas, rebaudioside A % content did not show any significant trend at differing irrigation criteria. The results indicate that maximizing dry leaf productivity directly affects the total rebaudioside A yield, which in turn can provide increased crop value to the grower. Irrigating near 10kPa produced higher dry leaf yield and total rebaudioside A yield, than irrigation at drier criteria. Irrigating stevia at 10 kPa at full canopy, the crop coefficient, k[subscript c], was equivalent to 0.97 ET₀, averaging 6.4 mm·d⁻¹ for the days measured. Close

• 548. [Image] The necessity for irrigation

  	An article espousing the efficiency and benefits of irrigation in agriculture. Includes photos of "Waiting for water: scene on the Truckee-Carson Project" and "Irrigation in southern California"
  	Citation × Citation Citation Abstract Copy Title: The necessity for irrigation Author: Pardee, George C. Year: 1906, 2005, 2004 An article espousing the efficiency and benefits of irrigation in agriculture. Includes photos of "Waiting for water: scene on the Truckee-Carson Project" and "Irrigation in southern California" Title: The necessity for irrigation Author: Pardee, George C. Year: 1906, 2005, 2004 An article espousing the efficiency and benefits of irrigation in agriculture. Includes photos of "Waiting for water: scene on the Truckee-Carson Project" and "Irrigation in southern California" Close