Actual evapotranspiration and dual crop coefficients for dry-seeded rice and hybrid maize grown with overhead sprinkler irrigation

2014 ◽  
Vol 136 ◽  
pp. 1-12 ◽  
Author(s):  
Ma. Carmelita R. Alberto ◽  
James R. Quilty ◽  
Roland J. Buresh ◽  
Reiner Wassmann ◽  
Sam Haidar ◽  
...  
Keyword(s):  
Sprinkler Irrigation ◽  
Actual Evapotranspiration ◽  
Crop Coefficients ◽  
Hybrid Maize ◽  
Overhead Sprinkler

Carbon uptake and water productivity for dry-seeded rice and hybrid maize grown with overhead sprinkler irrigation

2013 ◽  
Vol 146 ◽  
pp. 51-65 ◽  
Author(s):  
Ma. Carmelita R. Alberto ◽  
Roland J. Buresh ◽  
Takashi Hirano ◽  
Akira Miyata ◽  
Reiner Wassmann ◽  
...  
Keyword(s):  
Water Productivity ◽  
Sprinkler Irrigation ◽  
Carbon Uptake ◽  
Hybrid Maize ◽  
Overhead Sprinkler

Annual Evapotranspiration and Crop Coefficients of Ligustrum japonica Growing in Three Container Sizes

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 512c-512
Author(s):  
R.C. Beeson
Keyword(s):  
Reference Evapotranspiration ◽  
Actual Evapotranspiration ◽  
Rooted Cuttings ◽  
Supplemental Irrigation ◽  
Mean Size ◽  
Crop Coefficients ◽  
Marketable Size

The objective of this study was to determine crop coefficients (KC) for Ligustrum japonica growing in three container sizes using the Penman equation to calculate reference evapotranspiration (ETR). Rooted cuttings were transplanted into 3-liter containers and upcanned as needed into 10- and 23-L containers. Production was scheduled such that a series of plants in each container size were about 2 months from commercial marketable size every 4 months. Beginning 1 Jan. 1995 until 31 Dec. 1996, three uniform plants of each size were suspended in weighing lysimeters and surrounded by similar size plants filling an area 3.7 by 4.9 m. Plants within each area were overhead irrigated at 2000 h as needed, based on a 30% moisture allowed deficit. Plants were exchanged every 4 months such that the annual mean size was that of a marketable plant. Actual evapotranspiration (ETA) was calculated from half-hour measurements of each plant's weight and adjusted for rainfall. From these and daily calculated ETR, KC were determined for each size of container. KCs ranged from 1.06 to 1.50 when ETA was converted to mm/day based on allocated bed space. Comparisons of volumes of supplemental irrigation to ETA and effects of assumptions required in converting ETA to mm/day will be discussed.

scholarly journals Determination of Actual Evapotranspiration and Crop Coefficients of California Date Palms Using the Residual of Energy Balance Approach

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2253 ◽  
Author(s):  
Aliasghar Montazar ◽  
Robert Krueger ◽  
Dennis Corwin ◽  
Alireza Pourreza ◽  
Cayle Little ◽  
...  
Keyword(s):  
Energy Balance ◽  
Water Resources ◽  
Date Palm ◽  
Irrigation Management ◽  
Canopy Cover ◽  
Tree Height ◽  
Actual Evapotranspiration ◽  
Date Palms ◽  
The Mean ◽  
Crop Coefficients

As water scarcity becomes of greater concern in arid and semi-arid regions due to altered weather patterns, greater and more accurate knowledge regarding evapotranspiration of crops produced in these areas is of increased significance to better manage limited water resources. This study aimed at determining the actual evapotranspiration (ETa) and crop coefficients (Ka) in California date palms. The residual of energy balance method using a combination of surface renewal and eddy covariance techniques was applied to measure ETa in six commercial mature date palm orchards (8–22 years old) over one year. The experimental orchards represent various soil types and conditions, irrigation management practices, canopy characteristics, and the most common date cultivars in the region. The results demonstrated considerable variability in date palm consumptive water use, both spatially and temporally. The cumulative ETa (CETa) across the six sites ranged from 1299 to 1501 mm with a mean daily ETa of 7.2 mm day−1 in June–July and 1.0 mm day−1 in December at the site with the highest crop water consumption. The mean monthly Ka values varied between 0.63 (December) and 0.90 (June) in the non-salt-affected, sandy loam soil date palms with an average density of 120 plants ha−1 and an average canopy cover and tree height of more than 80% and 11.0 m, respectively. However, the values ranged from 0.62 to 0.75 in a silty clay loam saline-sodic date palm orchard with 55% canopy cover, density of 148 plants ha−1, and 7.3 m tree height. Inverse relationships were derived between the CETa and soil salinity (ECe) in the crop root zone; and between the mean annual Ka and ECe. This information addresses the immediate needs of date growers for irrigation management in the region and enables them to more efficiently utilize water and to achieve full economic gains in a sustainable manner, especially as water resources become less available or more expensive.

scholarly journals Monitoring Crop Evapotranspiration and Crop Coefficients over an Almond and Pistachio Orchard Throughout Remote Sensing

2018 ◽  
Author(s):  
Joaquim Bellvert ◽  
Karine Adeline ◽  
Shahar Baram ◽  
Lars Pierce ◽  
Blake Sanden ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Water Stress ◽  
Remotely Sensed ◽  
Actual Evapotranspiration ◽  
Water Evaporation ◽  
Landsat 8 ◽  
Crop Evapotranspiration ◽  
Crop Water ◽  
Field Scale ◽  
Crop Coefficients

In California, water is a perennial concern. As competition for water resources increases due to growth in population, California’s tree nut farmers are committed to improving the efficiency of water used for food production. There is an imminent need to have reliable methods that provide information about the temporal and spatial variability of crop water requirements, which allow farmers to make irrigation decisions at field scale. This study focuses on estimating the actual evapotranspiration and crop coefficients of an almond and pistachio orchard located in Central Valley (California) during an entire growing season by combining a simple crop evapotranspiration model with remote sensing data. A dataset of the vegetation index NDVI derived from Landsat-8 was used to facilitate the estimation of the basal crop coefficient (Kcb), or potential crop water use. The soil water evaporation coefficient (Ke) was measured from microlysimeters. The water stress coefficient (Ks) was derived from airborne remotely sensed canopy thermal-based methods, using seasonal regressions between the crop water stress index (CWSI) and stem water potential (Ystem). These regressions were statistically-significant for both crops, indicating clear seasonal differences in pistachios, but not in almonds. In almonds, the estimated maximum Kcb values ranged between 1.05 to 0.90, while for pistachios, it ranged between 0.89 to 0.80. The model indicated a difference of 97 mm in transpiration over the season between both crops. Soil evaporation accounted for an average of 16% and 13% of the total actual evapotranspiration for almonds and pistachios, respectively. Verification of the model-based daily crop evapotranspiration estimates was done using eddy-covariance and surface renewal data collected in the same orchards, yielding an r2 >= 0.7 and average root mean square errors (RMSE) of 0.74 and 0.91 mm day-1 for almond and pistachio, respectively. It is concluded that the combination of crop evapotranspiration models with remotely-sensed data is helpful for upscaling irrigation information from plant to field scale and thus may be used by farmers for making day-to-day irrigation management decisions.

scholarly journals Measurements of the actual evapotranspiration and crop coefficients of summer and winter seasons crops in Japan

2009 ◽  
Vol 55 (No. 3) ◽  
pp. 121-127 ◽  
Author(s):  
P. Attarod ◽  
M. Aoki
Keyword(s):  
Winter Season ◽  
Ground Surface ◽  
Crop Coefficient ◽  
Bowen Ratio ◽  
Irrigation Scheduling ◽  
Summer Season ◽  
Actual Evapotranspiration ◽  
Rye Grass ◽  
Balance Technique ◽  
Crop Coefficients

The main goal was to understand the trends of actual evapotranspiration (AET) and crop coefficient (<I>K<sub>c</sub></I>) in summer and winter seasons crops in Japan, maize, soybean, wheat and Italian rye-grass. Bowen ratio energy balance technique (BREB) was applied to measure the AET and heat flux between ground surface and atmosphere. Measurements were carried out using an automatic weather station (AWS) installed seasonally in the experimental farm of Tokyo University of Agriculture and Technology (TUAT). Penman-Monteith equation recommended by FAO was used to calculate reference crop evapotranspiration (ET<SUB>0</SUB>) and <I>K<sub>c</sub></I> was obtained from the ratio of AET to ET<SUB>0</SUB>. The results indicated that the average amount of daytime AET in the winter and summer seasons crops were approximately 2.5 and 3.5 mm, respectively monthly daytime. Daytime AET varied between 1.3 and 5.7 mm in winter season crops and between 1.4 and 6.5 mm in summer season crops. No significant differences between daily average values of AET for winter season as well as for summer season crops were found at 5% level of confidence (<I>t</I> = 0.9278, wheat and Italian rye-grass and <I>t</I> = 0.6781, soybean and maize). Average <I>K<sub>c</sub></I> values of summer season crops were found to be slightly higher than those of winter seasons crops. For planning the irrigation scheduling, it is quite necessary to understand the behaviors of AET and <I>K<sub>c</sub></I> during the growing season.

Sign in / Sign up

Export Citation Format

Share Document