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Joseph Foley - One of the best experts on this subject based on the ideXlab platform.
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Micrometeorology of Sprinkler Irrigation
Agricultural and Forest Meteorology, 2015Co-Authors: Nigel Hancock, Rod Smith, Jasim Uddin, Joseph FoleyAbstract:Evaporation during Sprinkler Irrigation involves complex and multiple micrometeorological changes at various stages as the crop canopy is wetted and subsequently dries. The advection of energy is important in this process, particularly with lateral move and centre pivot machines which are used to irrigate extensive areas of cropping and result in a moving patchwork of adjacent wetted and non-wetted areas. To investigate the significance and magnitude of all the terms involved in the energy budget of a Sprinkler irrigated crop, a study was conducted on a small area of cotton at the University of Southern Queensland, Australia using eddy covariance and ancillary measurements. The relevant theory is set out and all terms were quantified. Of the ‘minor’ terms in the energy balance, all but the advected energy were shown to be negligible or cancel other terms. The advected sensible heat DH and latent heat DV fluxes were shown to be significant in the energy budget, ranging from 1.5 to 14% of the available energy depending on prevailing meteorological conditions. This advection increased the evaporation from the irrigated area by adding energy (DH) and by removing water vapour (removing energy DV). Of the two terms, neglecting DH would result in a significant underestimate of the available energy for evaporation, and a corresponding underestimate of the actual evaporation. The methodology used, and theory as set out in this paper, provides the means to estimate the additional evaporation that occurs during Sprinkler Irrigation.
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Are evaporation losses in Sprinkler Irrigation high
2014Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Evaporation losses during Sprinkler Irrigation are perceived by the Irrigation community to be high and is a major impediment to the adoption of Sprinkler Irrigation. Previous overseas experimental studies have reported losses up to 45% of the applied water and that a large proportion of the loss is droplet evaporation. However, a recent field experimental study conducted over a cotton crop at the University of Southern Queensland showed that the total evaporation is low (about 8%) and that droplet evaporation would be less than 1%. The additional evaporation during Sprinkler Irrigation would be about 4% of the applied water.
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Estimation of canopy interception under Sprinkler Irrigation: a new approach
2014Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Interception of water on plant canopy and the subsequent evaporation into the atmosphere is an important part of the Irrigation scheduling and it is also considered as an important part of Irrigation water use efficiency analysis in agricultural crops. There are various methods that have been used to estimate the canopy interception during Sprinkler Irrigation but they all have severe limitations. We introduce a new method to estimate crop canopy interception during Sprinkler Irrigation using eddy covariance–sap flow measurements. In this method, total ET and sap flow were measured using eddy convince and sap flow system during Irrigation and nonIrrigation periods. The Irrigation trials were conducted in a cotton field using a small movable impact Sprinkler Irrigation system placing the eddy covariance and sap flow system in the centre of the field. The measurements show that during Irrigation the total ET increased significantly and the sap flow decreased remarkably. During the drying (post Irrigation) period total ET decreased exponentially and sap flow progressively recovered until completely dries the canopy. Canopy interception was estimated as the summation of additional evaporation of intercepted water and the reduction of sap flow during drying. The mean value of cotton canopy interception was found to be 0.30 mm which was roughly 3% of the applied water.
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Evaporation and sapflow dynamics during Sprinkler Irrigation of cotton
Agricultural Water Management, 2013Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Quantifying the various components of evapotranspiration during Sprinkler Irrigation is not only challenging but also difficult to measure and validate using traditional methods. In this paper, measurements of the varying rates of ET using precision energy budget/eddy covariance measurements and sapflow in cotton before, during and after Sprinkler Irrigation are reported. The trials were carried out at a small scale using small impact type Sprinkler Irrigation system. Nondimensionalisation of the measured ET and sapflow rates with respect to atmospheric evaporative demand permitted superposition and averaging of multiple time series of data for each of the three phases of Irrigation.
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Carbon dioxide flux as an indicator of crop transpiration during Sprinkler Irrigation
2013Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Accurate measurement of transpiration during Sprinkler Irrigation is vital to the partitioning of the total evapotranspiration into evaporation and transpiration. Although, sap flow has been used to infer transpiration in several studies, the transpiration could not be quantified reasonably from this measurement due to the existence of a time lag between transpiration and sap flow. Eddy covariance (ECV) is a reliable micrometeorological mass transfer method for measuring evaporation (Uddin et al. 2013). It also allows measurement of the net exchange of carbon dioxide (CO2) flux between the crop and the atmosphere. Since transpiration and exchange of CO2 are directly related, it is hypothesised that measurement of the exchange of CO2 during Irrigation can be used as an indicator to estimate the transpiration, thus avoiding the time lag. Hence, total ET and CO2 flux before, during and after Sprinkler Irrigation were measured using the ECV method. Sap flow was measured simultaneously using sap flow gauges. The measurements were carried out over a low pressure impact type Sprinkler Irrigation system during several Irrigations of a cotton crop at the Agricultural Station at USQ. Results indicated that during Irrigation the plants absorbed less CO2 as transpiration decreased and the total ET increased significantly. The study concluded that the net exchange of CO2 can be an indicator of the instantaneous transpiration of the crop during Sprinkler Irrigation.
José Cavero - One of the best experts on this subject based on the ideXlab platform.
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Relevance of Sprinkler Irrigation time of the day on alfalfa forage production
Agricultural Water Management, 2016Co-Authors: José Cavero, J.m. Faci, Antonio Martínez-cobAbstract:Nighttime Sprinkler Irrigation usually results in lower water losses and higher Irrigation uniformity compared with daytime Sprinkler Irrigation due to lower wind speed. However, daytime Sprinkler Irrigation modifies the microclimatic conditions within the crop canopy which could result in improved crop growth. We studied during three years the effect of daytime and nighttime Irrigation on the yield, N content, N uptake, water use efficiency, microclimate and canopy temperature of an alfalfa (Medicago sativa L.) crop irrigated with a solid-set Sprinkler system in a semiarid Mediterranean climate. Two Irrigation treatments were tested: daytime Irrigation and nighttime Irrigation. The same Irrigation amount was applied in both treatments (552 to 757mmyear−1). The water losses of daytime Irrigation (10%) tripled the water losses of nighttime Irrigation (3%). In one year, daytime Irrigation decreased the mean Christiansen coefficient of uniformity (CU) by 4% and the seasonal CU by 2%. Microclimatic and canopy temperature changes during Sprinkler Irrigation were higher for daytime Irrigation as compared to nighttime Irrigation. Daytime Irrigation slightly reduced the soil water content of the surface layer (0–0.3m). The actual seasonal crop evapotranspiration was slightly higher (+3.7%) in the daytime Irrigation treatment compared to the nighttime Irrigation treatment only in one of the years. The annual alfalfa forage yield (16 to 22 Mg ha−1), N content (3.16 to 3.38%), N uptake (514 to 740kgha−1) and water use efficiency (17.7 to 25.9kgha−1mm−1) were not affected by the Irrigation time of the day. Although nighttime Sprinkler Irrigation results in some water saving, daytime Sprinkler Irrigation of alfalfa can be performed if necessary.
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Daytime Sprinkler Irrigation Effects on Net Photosynthesis of Maize and Alfalfa
Agronomy Journal, 2013Co-Authors: Yenny Urrego-pereira, Antonio Martínez-cob, Victoria Fernández, José CaveroAbstract:14 Págs., 5 Tabls., 11 Figs.During Sprinkler Irrigation some water is lost due to drift and evaporation. After Irrigation, plant-intercepted water is lost due to evaporation. The water loss causes microclimatic changes, which may involve positive or negative plant physiological responses.\ud We studied the changes in net photosynthesis of maize (Zea mays L.) and alfalfa (Medicago sativa L.) associated with Irrigation\ud with a solid-set Sprinkler system. For each species, measurements were made simultaneously in two plots, one being irrigated and the other not being irrigated. Two automatic canopy chambers connected to two CO2 infrared gas analyzers were used. Sprinkler Irrigation decreased air temperature (1.5°C on maize, 1.7°C on alfalfa), air vapor pressure deficit (VPD) (0.44 kPa for both crops) and canopy temperature (5.1°C on maize, 5.9°C on alfalfa). Sprinkler Irrigation decreased maize net photosynthesis on 80% of\ud the days and the mean reduction was 19%. Sprinkler Irrigation increased alfalfa net photosynthesis on 36% of days, decreased it\ud on 14% of days, and had no effect on half of the days. The decrease of maize net photosynthesis during Sprinkler Irrigation was linked to the high leaf wettability (water contact angles from 60–80°) and the decrease in temperature below the optimum range for photosynthesis. The higher hydrophobicity of alfalfa leaves (water contact angles >120°) and the wide range of optimum temperature for alfalfa photosynthesis may be the reasons why photosynthesis remained unaffected by Sprinkler Irrigation. The results suggest that daytime Sprinkler Irrigation with solid-set should be avoided for maize but can be used for alfalfa.This work was supported by the projects AGL2007-66716-C03-01 and AGL2010-21681-C03-01 (Ministerio de Economía y\ud Competitividad) of Spanish Government. Y.F.\ud Urrego-Pereira had a FPI grant of the Spanish government.Peer reviewe
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Relevance of Sprinkler Irrigation Time and Water Losses on Maize Yield
Agronomy Journal, 2013Co-Authors: Yenny Urrego-pereira, Antonio Martínez-cob, José CaveroAbstract:9 Pags., 6 Tabls., 3 Figs.Daytime Sprinkler Irrigation with a solid-set system can result in higher water losses, lower uniformity, and lower maize (Zea mays L.) yield compared with nighttime Irrigation. We studied the relevance of Irrigation time (daytime or nighttime) and water losses (compensating them or not in the Irrigation applied) for the growth and yield of maize during 2 yr. The seasonal average Sprinkler water losses compensated ranged from 14 to 19% for daytime Irrigation and from 5 to 11% for nighttime Irrigation. The average Christiansen coefficient of uniformity (CU) was similar for daytime and nighttime Irrigation in 2009 (84%) but lower for daytime Irrigation (78%) than nighttime Irrigation (84%) in 2010. Daytime Irrigation decreased the maize grain yield by 9% in the year that the CU was reduced. Increasing the water applied to compensate the water losses increased the soil matric potential but did not increase maize yield. The lower Irrigation uniformity for daytime Sprinkler Irrigation compared with nighttime Sprinkler Irrigation seems to be a relevant reason for the yield reduction. Solid-set Sprinkler Irrigation systems for maize should be designed to minimize daytime Irrigation or to allow a high daytime Irrigation uniformity (>84%).This work was supported by the project AGL2007-66716-C03-01 (Ministerio de Economía y Competitividad of Spain).Peer reviewe
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effect of non uniform Sprinkler Irrigation and plant density on simulated maize yield
Agricultural Water Management, 2012Co-Authors: Montserrat Salmeron, Y F Urrego, Ramon Isla, José CaveroAbstract:Abstract Typical field conditions under Sprinkler Irrigation include low Irrigation uniformity and non-uniform plant density, which can affect the crop yield and the environmental impact of Irrigation. The effect of the uniformity of Sprinkler Irrigation and plant density on the variability of maize grain yield under semi-arid conditions was evaluated, and the relevance of the spatial variability of these two variables on the simulation of maize grain yield was tested with the DSSAT-CERES-Maize model (V 4.5). Experimental field data from three maize growing seasons (2006, 2009 and 2010) with nighttime or daytime Sprinkler Irrigation were used to test the model performance. Yield, Irrigation depths and plant density distribution were measured in 18 m × 18 m plots divided in 25 sub-plots. Regression analysis showed that the variability of plant density and seasonal Irrigation depth (due to Irrigation non-uniformity) was able to explain from 28 to 77% of the variability in maize grain yield for the experiments with a relatively high coefficient of uniformity (CU) (73–84%) and high plant density (more than 74,844 plants ha −1 ). Taking into account Irrigation depth distribution improved maize yield simulations compared to simulations with the average Irrigation water applied. The root mean square error ( RMSE ) decreased from 637 to 328 kg ha −1 . Maize yield was over-predicted by 3% when Irrigation depth distribution was not considered. Including plant density distribution in the simulations did not improve maize yield simulations. The simulated decrease in maize yield with decreasing CU of Irrigation from 100 to 70% varied from year to year and caused reductions in yield ranging from 0.75 to 2.5 Mg ha −1 . The ability of the model to simulate CU effects on maize yield is shown.
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Simulation of Sprinkler Irrigation water uniformity impact on corn yield
Spanish Journal of Agricultural Research, 2010Co-Authors: Farida Dechmi, Enrique Playán, J.m. Faci, José CaveroAbstract:In a previous work, the spatial and temporal wind effects on corn yield were analysed using Ador-Crop (based on the FAO crop model CropWat) and a solid set Sprinkler Irrigation model. The combined model could explain only 25% of the variability of measured yield. The objective of this work was to evaluate the predictive capacity of two more advanced crop models (EPICphase and DSSAT) when coupled to the solid set Sprinkler Irrigation model. EPICphase explained 44% of total dry mater (TDM) and grain yield (GY) variability when measured Irrigation was used. The combination of EPICphase and the solid set Sprinkler Irrigation model explained better the variability of TDM than that of GY (42% and 35%, respectively), although the error in the estimation of GY with the coupled model was higher than when measured Irrigation doses were considered (1.55 t ha ‐1 vs. 1.22 t ha ‐1 ). The DSSAT model explained 39% and 38% of the variability in TDM and GY, respectively, when measured Irrigation data was used. When DSSAT was considered in the coupled model, better results were obtained for TDM (R 2 = 41%) than GY (R 2 = 31%). The EPICphase model simulated grain yield more accurately than the DSSAT model because it produced a better prediction of the maximum LAI. The combination of the Sprinkler Irrigation model with the EPICphase or DSSAT models simulated crop growth and yield more accurately than when combined with the Ador-Crop model. Additional key words: DSSAT; EPICphase; Sprinkler Irrigation model; water deficit; wind. Resumen
Jasim Uddin - One of the best experts on this subject based on the ideXlab platform.
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Micrometeorology of Sprinkler Irrigation
Agricultural and Forest Meteorology, 2015Co-Authors: Nigel Hancock, Rod Smith, Jasim Uddin, Joseph FoleyAbstract:Evaporation during Sprinkler Irrigation involves complex and multiple micrometeorological changes at various stages as the crop canopy is wetted and subsequently dries. The advection of energy is important in this process, particularly with lateral move and centre pivot machines which are used to irrigate extensive areas of cropping and result in a moving patchwork of adjacent wetted and non-wetted areas. To investigate the significance and magnitude of all the terms involved in the energy budget of a Sprinkler irrigated crop, a study was conducted on a small area of cotton at the University of Southern Queensland, Australia using eddy covariance and ancillary measurements. The relevant theory is set out and all terms were quantified. Of the ‘minor’ terms in the energy balance, all but the advected energy were shown to be negligible or cancel other terms. The advected sensible heat DH and latent heat DV fluxes were shown to be significant in the energy budget, ranging from 1.5 to 14% of the available energy depending on prevailing meteorological conditions. This advection increased the evaporation from the irrigated area by adding energy (DH) and by removing water vapour (removing energy DV). Of the two terms, neglecting DH would result in a significant underestimate of the available energy for evaporation, and a corresponding underestimate of the actual evaporation. The methodology used, and theory as set out in this paper, provides the means to estimate the additional evaporation that occurs during Sprinkler Irrigation.
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Are evaporation losses in Sprinkler Irrigation high
2014Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Evaporation losses during Sprinkler Irrigation are perceived by the Irrigation community to be high and is a major impediment to the adoption of Sprinkler Irrigation. Previous overseas experimental studies have reported losses up to 45% of the applied water and that a large proportion of the loss is droplet evaporation. However, a recent field experimental study conducted over a cotton crop at the University of Southern Queensland showed that the total evaporation is low (about 8%) and that droplet evaporation would be less than 1%. The additional evaporation during Sprinkler Irrigation would be about 4% of the applied water.
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Estimation of canopy interception under Sprinkler Irrigation: a new approach
2014Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Interception of water on plant canopy and the subsequent evaporation into the atmosphere is an important part of the Irrigation scheduling and it is also considered as an important part of Irrigation water use efficiency analysis in agricultural crops. There are various methods that have been used to estimate the canopy interception during Sprinkler Irrigation but they all have severe limitations. We introduce a new method to estimate crop canopy interception during Sprinkler Irrigation using eddy covariance–sap flow measurements. In this method, total ET and sap flow were measured using eddy convince and sap flow system during Irrigation and nonIrrigation periods. The Irrigation trials were conducted in a cotton field using a small movable impact Sprinkler Irrigation system placing the eddy covariance and sap flow system in the centre of the field. The measurements show that during Irrigation the total ET increased significantly and the sap flow decreased remarkably. During the drying (post Irrigation) period total ET decreased exponentially and sap flow progressively recovered until completely dries the canopy. Canopy interception was estimated as the summation of additional evaporation of intercepted water and the reduction of sap flow during drying. The mean value of cotton canopy interception was found to be 0.30 mm which was roughly 3% of the applied water.
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Evaporation and sapflow dynamics during Sprinkler Irrigation of cotton
Agricultural Water Management, 2013Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Quantifying the various components of evapotranspiration during Sprinkler Irrigation is not only challenging but also difficult to measure and validate using traditional methods. In this paper, measurements of the varying rates of ET using precision energy budget/eddy covariance measurements and sapflow in cotton before, during and after Sprinkler Irrigation are reported. The trials were carried out at a small scale using small impact type Sprinkler Irrigation system. Nondimensionalisation of the measured ET and sapflow rates with respect to atmospheric evaporative demand permitted superposition and averaging of multiple time series of data for each of the three phases of Irrigation.
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Carbon dioxide flux as an indicator of crop transpiration during Sprinkler Irrigation
2013Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Accurate measurement of transpiration during Sprinkler Irrigation is vital to the partitioning of the total evapotranspiration into evaporation and transpiration. Although, sap flow has been used to infer transpiration in several studies, the transpiration could not be quantified reasonably from this measurement due to the existence of a time lag between transpiration and sap flow. Eddy covariance (ECV) is a reliable micrometeorological mass transfer method for measuring evaporation (Uddin et al. 2013). It also allows measurement of the net exchange of carbon dioxide (CO2) flux between the crop and the atmosphere. Since transpiration and exchange of CO2 are directly related, it is hypothesised that measurement of the exchange of CO2 during Irrigation can be used as an indicator to estimate the transpiration, thus avoiding the time lag. Hence, total ET and CO2 flux before, during and after Sprinkler Irrigation were measured using the ECV method. Sap flow was measured simultaneously using sap flow gauges. The measurements were carried out over a low pressure impact type Sprinkler Irrigation system during several Irrigations of a cotton crop at the Agricultural Station at USQ. Results indicated that during Irrigation the plants absorbed less CO2 as transpiration decreased and the total ET increased significantly. The study concluded that the net exchange of CO2 can be an indicator of the instantaneous transpiration of the crop during Sprinkler Irrigation.
Nigel Hancock - One of the best experts on this subject based on the ideXlab platform.
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Micrometeorology of Sprinkler Irrigation
Agricultural and Forest Meteorology, 2015Co-Authors: Nigel Hancock, Rod Smith, Jasim Uddin, Joseph FoleyAbstract:Evaporation during Sprinkler Irrigation involves complex and multiple micrometeorological changes at various stages as the crop canopy is wetted and subsequently dries. The advection of energy is important in this process, particularly with lateral move and centre pivot machines which are used to irrigate extensive areas of cropping and result in a moving patchwork of adjacent wetted and non-wetted areas. To investigate the significance and magnitude of all the terms involved in the energy budget of a Sprinkler irrigated crop, a study was conducted on a small area of cotton at the University of Southern Queensland, Australia using eddy covariance and ancillary measurements. The relevant theory is set out and all terms were quantified. Of the ‘minor’ terms in the energy balance, all but the advected energy were shown to be negligible or cancel other terms. The advected sensible heat DH and latent heat DV fluxes were shown to be significant in the energy budget, ranging from 1.5 to 14% of the available energy depending on prevailing meteorological conditions. This advection increased the evaporation from the irrigated area by adding energy (DH) and by removing water vapour (removing energy DV). Of the two terms, neglecting DH would result in a significant underestimate of the available energy for evaporation, and a corresponding underestimate of the actual evaporation. The methodology used, and theory as set out in this paper, provides the means to estimate the additional evaporation that occurs during Sprinkler Irrigation.
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Are evaporation losses in Sprinkler Irrigation high
2014Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Evaporation losses during Sprinkler Irrigation are perceived by the Irrigation community to be high and is a major impediment to the adoption of Sprinkler Irrigation. Previous overseas experimental studies have reported losses up to 45% of the applied water and that a large proportion of the loss is droplet evaporation. However, a recent field experimental study conducted over a cotton crop at the University of Southern Queensland showed that the total evaporation is low (about 8%) and that droplet evaporation would be less than 1%. The additional evaporation during Sprinkler Irrigation would be about 4% of the applied water.
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Estimation of canopy interception under Sprinkler Irrigation: a new approach
2014Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Interception of water on plant canopy and the subsequent evaporation into the atmosphere is an important part of the Irrigation scheduling and it is also considered as an important part of Irrigation water use efficiency analysis in agricultural crops. There are various methods that have been used to estimate the canopy interception during Sprinkler Irrigation but they all have severe limitations. We introduce a new method to estimate crop canopy interception during Sprinkler Irrigation using eddy covariance–sap flow measurements. In this method, total ET and sap flow were measured using eddy convince and sap flow system during Irrigation and nonIrrigation periods. The Irrigation trials were conducted in a cotton field using a small movable impact Sprinkler Irrigation system placing the eddy covariance and sap flow system in the centre of the field. The measurements show that during Irrigation the total ET increased significantly and the sap flow decreased remarkably. During the drying (post Irrigation) period total ET decreased exponentially and sap flow progressively recovered until completely dries the canopy. Canopy interception was estimated as the summation of additional evaporation of intercepted water and the reduction of sap flow during drying. The mean value of cotton canopy interception was found to be 0.30 mm which was roughly 3% of the applied water.
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Evaporation and sapflow dynamics during Sprinkler Irrigation of cotton
Agricultural Water Management, 2013Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Quantifying the various components of evapotranspiration during Sprinkler Irrigation is not only challenging but also difficult to measure and validate using traditional methods. In this paper, measurements of the varying rates of ET using precision energy budget/eddy covariance measurements and sapflow in cotton before, during and after Sprinkler Irrigation are reported. The trials were carried out at a small scale using small impact type Sprinkler Irrigation system. Nondimensionalisation of the measured ET and sapflow rates with respect to atmospheric evaporative demand permitted superposition and averaging of multiple time series of data for each of the three phases of Irrigation.
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Carbon dioxide flux as an indicator of crop transpiration during Sprinkler Irrigation
2013Co-Authors: Jasim Uddin, Rod Smith, Nigel Hancock, Joseph FoleyAbstract:Accurate measurement of transpiration during Sprinkler Irrigation is vital to the partitioning of the total evapotranspiration into evaporation and transpiration. Although, sap flow has been used to infer transpiration in several studies, the transpiration could not be quantified reasonably from this measurement due to the existence of a time lag between transpiration and sap flow. Eddy covariance (ECV) is a reliable micrometeorological mass transfer method for measuring evaporation (Uddin et al. 2013). It also allows measurement of the net exchange of carbon dioxide (CO2) flux between the crop and the atmosphere. Since transpiration and exchange of CO2 are directly related, it is hypothesised that measurement of the exchange of CO2 during Irrigation can be used as an indicator to estimate the transpiration, thus avoiding the time lag. Hence, total ET and CO2 flux before, during and after Sprinkler Irrigation were measured using the ECV method. Sap flow was measured simultaneously using sap flow gauges. The measurements were carried out over a low pressure impact type Sprinkler Irrigation system during several Irrigations of a cotton crop at the Agricultural Station at USQ. Results indicated that during Irrigation the plants absorbed less CO2 as transpiration decreased and the total ET increased significantly. The study concluded that the net exchange of CO2 can be an indicator of the instantaneous transpiration of the crop during Sprinkler Irrigation.
J. M. Tarjuelo Martín-benito - One of the best experts on this subject based on the ideXlab platform.
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Analysis of water application cost with permanent set Sprinkler Irrigation systems
Irrigation Science, 2004Co-Authors: J. Montero Martínez, R. S. Martínez, J. M. Tarjuelo Martín-benitoAbstract:In order to identify the subunit design incurring the lowest costs, it is necessary to consider various factors, thereby assuring the correct hydraulic performance of the subunit. Water application costs with a Sprinkler Irrigation system comprise: investment cost (pumps plant, pipes, Sprinklers, ditches), energy, manpower, maintenance and water costs. This work analyses the influence of different design and performance factors, such as subunit arrangement, spacing, working pressure, average application rate, and application efficiency on water application costs in a permanent set Sprinkler Irrigation subunit. The results show that the most important factor is the spacing between Sprinklers. The next most important factor is the shape of the subunit (number of laterals and number of Sprinklers per lateral). Working pressure is important too, since a decrease in pressure will result in a decrease in energy costs, although pipe diameter will need to increase. The higher the average application rate of the system, the higher the water application cost. The influence of Irrigation efficiency is higher as water price increases. The water application cost can be reduced by 40% when application efficiency increases from 60% to 90%.
