scholarly journals Low-Energy Precision Application (LEPA) Irrigation: A Forty-Year Review

2019 ◽  
Vol 62 (5) ◽  
pp. 1343-1353 ◽  
Author(s):  
James P. Bordovsky

Abstract. The low-energy precision application (LEPA) irrigation concept was developed 40 years ago (ca. 1978) to address the depletion of irrigation water from the Ogallala Aquifer and the sharp increase in pumping costs caused by the 1970s fuel crisis occurring at that time in the Texas High Plains. The LEPA method applies water to the soil surface at low pressure using a tower-truss irrigation system that continually moves through the field. This method brought changes in irrigation equipment and management that resulted in improvements in water productivity, particularly in semi-arid locations with diminishing water supplies. A review of published information pertaining to LEPA history, evaluation, and usage was performed. On landscapes of less than 1% slope, negative crop yield effects caused by irrigation runoff and start-stop system alignment were overcome with appropriately spaced basins, or furrow checks, and multiple irrigations over the course of the growing season. No consistent yield advantage at any level of irrigation was documented by placing water in every furrow (1 m spacing) compared to alternate furrows (2 m spacing). In irrigation treatments having =50% of the estimated full irrigation quantity, LEPA resulted in a 16% yield increase over sprinkler methods, although subsurface drip irrigation (SDI) resulted in a 14% yield increase over LEPA. At irrigation levels >50% of full irrigation, crop yields of sprinkler treatments were only slightly less than those of LEPA, and SDI yields were 7% greater than LEPA. The LEPA irrigation method was the catalyst for innovations in chemigation, no-till planting, and site-specific irrigation. As irrigation water becomes more limited, use and proper management of optimum irrigation methods will be critical. Keywords: Basin tillage, Chemigation, Evapotranspiration, Irrigation methods, LEPA, Low-energy precision application, Runoff, Spray irrigation, Sprinkler irrigation, Uniformity, Water use efficiency.

2017 ◽  
Vol 9 (2) ◽  
pp. 399-409 ◽  
Author(s):  
Hussein M. Al-Ghobari ◽  
Ahmed Z. Dewidar

AbstractAn in-situ field study on two types of irrigation methods and three irrigation regimes was conducted in a sandy loam soil located at King Saud University, Riyadh, Saudi Arabia in 2015 and 2016. The study was to assess the effects of different irrigation methods on physiological and yield responses of tomato crops under water shortage conditions. The tested irrigation methods were surface drip irrigation (SDI) and subsurface drip irrigation (SSDI) systems. Irrigation treatments consisted of three strategies: (1) plants were irrigated with a water depth of 100% of the full irrigation supply; (2) plants were irrigated with a water depth of 80% of the full irrigation supply; and (3) plants were irrigated with a water depth of 60% of the full irrigation supply. Results indicated that water shortage significantly affected yield and quality response for each season. Over a 2-year average, yield increase was greatest in T1-SSDI followed by T2-SSDI and then T1-SDI. The yield response factor was 0.95 and 1.05 for SSDI and SDI, respectively. The highest water use efficiency values were obtained in T2-SSDI (16.3 kg m−3) and T1-SSDI (15.6 kg m−3), and the lowest ones, those estimated in T1-SDI (10.9 kg m−3) and T3-SDI (9.5 kg m−3).


Author(s):  
Kasa Mekonen Tiku ◽  
Shushay Hagoes ◽  
Berhane Yohanes

The study was carried out at the effect of drip and surface irrigation (Furrow irrigation) methods on onion and sesame crops from December 2011 to May 2012 in the Tigray region of Northwest Ethiopia. The objective was to evaluate the family drip irrigation system in comparison with furrow irrigation system in terms of irrigation water productivity (using 100% ETc for both commodities). The water saved in drip irrigation over furrow irrigation was found to be 33% for onion and sesame crops. The irrigation water productivity of onion was 0.9 kg/m3 and 0.55 kg/m3 under drip and furrow irrigation methods respectively. The irrigation water productivity of sesame was 0.14 kg/m3 and 0.045 kg/m3 under drip and furrow irrigation methods respectively.


2019 ◽  
Vol 10 ◽  
pp. 3384-3388
Author(s):  
Prof.RAE. Z.H. Aliyev

It should be recognized that the Republic of Azerbaijan has a leash of 14% of the water supply in the whole of Transcaucasia. Then, when the interim water balance of the republic is 32.29 million km3. However, in the best case, the water years with a 95% supply due to neighboring water atheria, this figure reaches up to 20 million km , as well as in shallow years, the republic will only reduce it to 17.0 million km3. water. That is, there is an acute shortage of water in the country. For the rational use of already limited water resources, it is necessary to switch to modern progressive irrigation methods using small-scale mechanization and automation of irrigation. The current technical equipment for irrigation does not always meet the requirements of the specific conditions of Azerbaijan. Our proposed irrigation system can be successfully used in various soil, climatic and difficult geographic conditions in the country, which was tested in the country with certifying indicators as crop yields increased to 38-50%, when irrigation water of 3 or more was saved times, while maintaining the ecological balance of the environment.


Water ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 530 ◽  
Author(s):  
Tewodros Assefa ◽  
Manoj Jha ◽  
Manuel Reyes ◽  
Seifu Tilahun ◽  
Abeyou Worqlul

A field-scale experimental study was conducted in Sub-Saharan Africa (Ethiopia and Ghana) to examine the effects of conservation agriculture (CA) with drip irrigation system on water productivity in vegetable home gardens. CA here refers to minimum soil disturbance (no-till), year-round organic mulch cover, and diverse cropping in the rotation. A total of 28 farmers (13 farmers in Ethiopia and 15 farmers in Ghana) participated in this experiment. The experimental setup was a paired ‘t’ design on a 100 m2 plot; where half of the plot was assigned to CA and the other half to conventional tillage (CT), both under drip irrigation system. Irrigation water use and crop yield were monitored for three seasons in Ethiopia and one season in Ghana for vegetable production including garlic, onion, cabbage, tomato, and sweet potato. Irrigation water use was substantially lower under CA, 18% to 45.6%, with a substantial increase in crop yields, 9% to about two-fold, when compared with CT practice for the various vegetables. Crop yields and irrigation water uses were combined into one metric, water productivity, for the statistical analysis on the effect of CA with drip irrigation system. One-tailed paired ‘t’ test statistical analysis was used to examine if the mean water productivity in CA is higher than that of CT. Water productivity was found to be significantly improved (α = 0.05) under the CA practice; 100%, 120%, 222%, 33%, and 49% for garlic, onion, tomato, cabbage, and sweet potato respectively. This could be due to the improvement of soil quality and structure due to CA practice, adding nutrients to the soil and sticking soil particles together (increase soil aggregates). Irrigation water productivity for tomato under CA (5.17 kg m−3 in CA as compared to 1.61 kg m−3 in CT) is found to be highest when compared to water productivity for the other vegetables. The mulch cover provided protection for the tomatoes from direct contact with the soil and minimized the chances of soil-borne diseases. Adapting to CA practices with drip irrigation in vegetable home gardens is, therefore, a feasible strategy to improve water use efficiency, and to intensify crop yield, which directly contributes towards the sustainability of livelihoods of smallholder farmers in the region.


2015 ◽  
Vol 19 (7) ◽  
pp. 3073-3091 ◽  
Author(s):  
J. Jägermeyr ◽  
D. Gerten ◽  
J. Heinke ◽  
S. Schaphoff ◽  
M. Kummu ◽  
...  

Abstract. Global agricultural production is heavily sustained by irrigation, but irrigation system efficiencies are often surprisingly low. However, our knowledge of irrigation efficiencies is mostly confined to rough indicative estimates for countries or regions that do not account for spatiotemporal heterogeneity due to climate and other biophysical dependencies. To allow for refined estimates of global agricultural water use, and of water saving and water productivity potentials constrained by biophysical processes and also non-trivial downstream effects, we incorporated a process-based representation of the three major irrigation systems (surface, sprinkler, and drip) into a bio- and agrosphere model, LPJmL. Based on this enhanced model we provide a gridded world map of irrigation efficiencies that are calculated in direct linkage to differences in system types, crop types, climatic and hydrologic conditions, and overall crop management. We find pronounced regional patterns in beneficial irrigation efficiency (a refined irrigation efficiency indicator accounting for crop-productive water consumption only), due to differences in these features, with the lowest values (< 30 %) in south Asia and sub-Saharan Africa and the highest values (> 60 %) in Europe and North America. We arrive at an estimate of global irrigation water withdrawal of 2469 km3 (2004–2009 average); irrigation water consumption is calculated to be 1257 km3, of which 608 km3 are non-beneficially consumed, i.e., lost through evaporation, interception, and conveyance. Replacing surface systems by sprinkler or drip systems could, on average across the world's river basins, reduce the non-beneficial consumption at river basin level by 54 and 76 %, respectively, while maintaining the current level of crop yields. Accordingly, crop water productivity would increase by 9 and 15 %, respectively, and by much more in specific regions such as in the Indus basin. This study significantly advances the global quantification of irrigation systems while providing a framework for assessing potential future transitions in these systems. In this paper, presented opportunities associated with irrigation improvements are significant and suggest that they should be considered an important means on the way to sustainable food security.


2019 ◽  
Vol 62 (5) ◽  
pp. 1377-1393
Author(s):  
Steven R. Evett ◽  
Gary W. Marek ◽  
Paul D. Colaizzi ◽  
David K. Brauer ◽  
Susan A. O’Shaughnessy

Abstract. Greater than 80% of the irrigated area in the Southern High Plains is served by center-pivot irrigation, but the area served by subsurface drip irrigation (SDI) is increasing due to several factors including declining well yields and improved yields and crop water productivity (CWP), particularly for cotton. Not as well established is the degree to which the reduced soil water evaporation (E) in SDI systems affects the soil water balance, water available to the crop, and overall water savings. Grain corn ( L.) and sorghum ( L. Moench) were grown on four large weighing lysimeters at Bushland, Texas, in 2013 (corn), 2014 and 2015 (sorghum), and 2016 (corn). Evapotranspiration (ET) was measured using the lysimeters and using a neutron probe in the surrounding fields. Two of the lysimeters and surrounding fields were irrigated with SDI, and the other two were irrigated with mid-elevation spray application (MESA). The lysimeter-measured evaporative losses were 149 to 151 mm greater from sprinkler-irrigated corn fields than from SDI fields. When growing sorghum, the lysimeter-measured evaporative losses were 44 to 71 mm greater from sprinkler-irrigated fields than from SDI fields. The differences were affected by plant height and became smaller when plant height reached the height of the spray nozzles, indicating that the use of LEPA or LESA nozzles could decrease the evaporative losses from sprinkler-irrigated fields in this region with its high evaporative demand. Annual weather patterns also influenced the differences in evaporative loss, with increased differences in dry years. SDI reduced overall corn water use by 13% to 15%, as determined by neutron probe, while either not significantly affecting yield (2016) or increasing yield by up to 19% (2013) and increasing CWP by 37% (2013) to 13% (2016) as compared with MESA full irrigation. However, sorghum yield decreased by 15% and CWP decreased by 14% in 2014 when using SDI compared with MESA full irrigation due to an overly wet soil profile in the SDI fields and deep percolation that likely caused nutrient losses. In 2015, there were no significant sorghum yield differences between irrigation methods. Sorghum CWP was significantly greater (by 14%) in one SDI field in 2015 compared with MESA fully irrigated sorghum. Overall, sorghum CWP increased by 8% for SDI compared with MESA full irrigation in 2015. These results indicate that SDI will be successful for corn production in the Texas High Plains, but SDI is unlikely to benefit sorghum production. Keywords: Corn, Crop water productivity, Evaporative loss, Evapotranspiration, Irrigation application method, Sorghum, Water use efficiency, Weighing lysimeter.


Author(s):  
Aikaterini Lyra ◽  
Athanasios Loukas ◽  
Pantelis Sidiropoulos

Abstract Irrigation and nitrate fertilization scenarios were combined and simulated for the crop water irrigation demands and nitrogen applications based on experiments on crop cultivation practices. Two irrigation practices of deficit irrigation and rainfed conditions were applied in the main crop types of the Almyros Basin, a coastal basin located in Thessaly, Greece. The groundwater system of Almyros suffers from progressive water balance deficit, nitrate contamination and seawater intrusion due to the groundwater abstractions for agricultural irrigation to cover crop water demands in the dry season. The impacts of the irrigation and nitrate fertilization scenarios on groundwater resources quantity and quality were simulated with the Integrated Modelling System consisting of models of surface hydrology (UTHBAL), groundwater hydrology (MODFLOW), crop growth/nitrates leaching (REPIC), contaminant transport (MT3DMS), and seawater intrusion (SEAWAT), for the historical period of 1991–2018. The results of the scenarios were evaluated with the indicators of Crop Water Productivity (CWP) for crop yields and irrigation water, Partial Factor Productivity (PFP) for Nitrogen Use Efficiency, and Economic Water Productivity (EWP) for the gross profits of irrigation water.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
H. S. Jat ◽  
P. C. Sharma ◽  
Ashim Datta ◽  
Madhu Choudhary ◽  
S. K. Kakraliya ◽  
...  

AbstractA study was conducted to design productive, profitable, irrigation water¸ nitrogen and energy use efficient intensive cereal systems (rice-wheat; RW and maize-wheat; MW) in North-West India. Bundling of conservation agriculture (CA) with sub-surface drip irrigation termed as CA+ were compared with CA alone and conventional tillage based and flood irrigated RW rotation (farmer’s practice; ScI). In contrast to conventional till RW rotation which consumed 1889 mm ha−1 irrigation water (2-yr mean), CA+ system saved 58.4 and 95.5% irrigation water in RW and MW rotations, respectively. CA+ practices saved 45.8 and 22.7% of irrigation water in rice and maize, respectively compared to CA with flood irrigation. On a system basis, CA+ practices saved 46.7 and 44.7% irrigation water under RW (ScV) and MW (ScVI) systems compared to their respective CA-based systems with flood irrigation (ScIII and ScIV). CA+ in RW system recorded 11.2% higher crop productivity and improved irrigation water productivity by 145% and profitability by 29.2% compared to farmers’ practice. Substitution of rice with maize (MW system; ScVI) recorded 19.7% higher productivity, saved 84.5% of irrigation water and increased net returns by 48.9% compared to farmer’s practice. CA+ RW and MW system improved energy productivity by 75 and 169% and partial factor productivity of N by 44.6 and 49.6%, respectively compared to ScI. The sub-surface drip irrigation system saved the fertilizer N by 20% under CA systems. CA+ in RW and MW systems recorded ~13 and 5% (2-yr mean) higher profitability with 80% subsidy on installing sub-surface drip irrigation system and similar profitability without subsidy scenario compared with their respective flood irrigated CA-based systems.


Agronomy ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1265
Author(s):  
Maged Elsayed Ahmed Mohammed ◽  
Mohammed Refdan Alhajhoj ◽  
Hassan Muzzamil Ali-Dinar ◽  
Muhammad Munir

Water scarcity is a major constraint in arid and semi-arid regions. Crops that require less irrigation water and those, which are considered drought-tolerant such as date palm (Phoenix dactylifera L.), are dominant in these regions. Despite the tolerance of these crops, the development of technologies that ensure efficient use of irrigation water is imperative. Taking these issues into consideration, the study was conducted to investigate the impact of limited irrigation water using a new subsurface irrigation system (SSI) on gas exchange, chlorophyll content, water use efficiency, water productivity, fruit physicochemical characteristics, and yield of date palm (cv. Sheshi). The impact of the SSI system was compared with two surface irrigation systems, namely, surface drip irrigation (SDI) and surface bubbler irrigation (SBI). The field experiment was carried out during 2018 and 2019 at the Date Palm Research Center of Excellence, King Faisal University, Kingdom of Saudi Arabia. The annual crop evapotranspiration (ETc) was 2544 mm. The applied irrigation water was set at 50%, 75%, and 125% of ETc for SSI, SDI, and SBI, respectively, which were based on the higher crop water productivity recorded in an initial field study. The total annual volume of water applied for SSI, SDI, and SBI was 22.89, 34.34, and 57.24 m3 palm−1, respectively. The crop water productivity (CWP) at the SSI system was significantly higher, with a value of 1.15 kg m−3, compared to the SDI (0.51 kg m−3) and SBI systems (0.37 kg m−3). The photosynthetic water use efficiency (WUE) was 10.09, 9.96, and 9.56 μmol CO2 mmol−1 H2O for SSI, SBI, and SDI, respectively. The maximum chlorophyll content (62.4 SPAD) was observed in SBI, followed by SSI (58.9 SPAD) and SDI (56.9 SPAD). Similarly, net photosynthesis and the transpiration rate were significantly higher in SBI and lowest in SSI. However, the SSI system substantially increased palm yield and enhanced fruit quality. The new SSI system, through its positive impact on the efficiency of irrigation water use and enhancement on fruit yield and fruit quality of date palm, seems quite suitable for the irrigation of palm trees in arid and semi-arid regions.


2021 ◽  
Vol 13 (2) ◽  
pp. 677-685
Author(s):  
O. P. Singh ◽  
P. K. Singh

With the growing irrigation water scarcity, the researchers and policymakers are more concerned to improve the irrigation water use efficiency at farmers’ field level. The water-saving technologies provide greater control over water delivery to the crop root zone and reduce the non-beneficial evaporation from the crop field. Water productivity is an important concept for measuring and comparing water use efficiency. The present study tried to estimate the irrigation water use and physical water productivity of cotton under alternate furrow and drip irrigation methods in the Bhavnagar district of Gujarat. Results suggest that crop yield and physical water productivity were higher for cotton irrigated by drip method than alternate furrow method during normal rainfall and drought year. The irrigation water use under the drip method of irrigation was lower as compared to the alternate furrow method. In the case of total water (effective rainfall + irrigation water) use, per hectare crop yield and physical water productivity were higher for the drip method of irrigation than the alternate furrow method of irrigating cotton crop during normal rainfall and drought year. In the case of total water use (effective rainfall + irrigation water), it was lower for drip irrigation than the alternate furrow method of irrigating cotton crop during normal rainfall year and drought year. While estimating total water (effective rainfall + irrigation water) use, it was assumed that there is no return flow of water from the cotton field in the study area under both irrigation methods.


Sign in / Sign up

Export Citation Format

Share Document