Irrigation scheduling and water requirements for cowpea using evaporation pan at middle of Iraq

The present study was conducted to find out the water requirements and most suitable irrigation frequencies for cowpea (Vigna unguiculata L.) var grown under drip irrigation. The treatments were based on the IW:CPE ratio at different empirical pan factors 0.6 , 0.8, 1.0, 1.,1.4 , and 1.6 Ef (where Ef = IW/CPE). It was observed that the irrigation interval was variable values decreased by increasing Ef value and with the progress of the growing season. The 1.2 and 1.0 IW: CPE treatments with approximately 4 days irrigation interval were achieved the best results. The total amount of applied water during Cowpea growing season was varied between 247.7 and 266.5mm with 254.8mm as a mean. Irrigation treatment with Ef1.2 was superior over the rest of other treatments in fresh seed yield (5.13 ton.hec.-1), crop water productivity (2.14 kg.m-3), biological yield (6.88 ton.hec.-1) , fresh pod yield (7.33 ton.hec.-1), weight of 100 seed (31.28gm), number of seed/pod (9.34) and netting percentage (37.1). The lowest values of the most parameters used in this study were obtained by Ef 0.6 irrigation treatment.

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Impact of Irrigation Methods, Irrigation Scheduling and Mulching on Seed Yield and Water Productivity of Chickpea (Cicer arietinum)

Legume Research - An International Journal ◽

10.18805/lr-4188 ◽

2019 ◽

Author(s):

P R Kumar ◽

Santosh S Mali ◽

A K Singh ◽

B P Bhatt

Keyword(s):

Seed Yield ◽

Drip Irrigation ◽

Water Productivity ◽

Control Plant ◽

Irrigation Scheduling ◽

Irrigation Methods ◽

Hill Region ◽

Irrigation Interval ◽

Basin Irrigation ◽

Horizontal Spread

An experiment was conducted to test the efficacy of irrigation methods and mulching in seed production of chickpea. Irrigation methods included drip with mulch (DM), drip without mulch (DNM) and check basin (CB) irrigation. Drip irrigation was scheduled at 1-day, 2-day and 7 days interval, while farmers’ practice of check basin irrigation at 7-day interval was considered as control. Plant parameters like height, horizontal spread, dry matter, root length and root spread, and number of pods were significantly influenced by irrigation levels and mulch. Seed yield of 17.7 and 16.8 q/ha was recorded for DM having 1-day and 2-day interval, respectively, which was about 82 and 73% higher over the control. The harvest index increased with increasing irrigation interval and was highest (57.4) under treatments with longer irrigation interval (DM7, DNM7 and CB7). Drip irrigation at 1-day and 2-day interval recorded the water productivities of 0.54 and 0.52 kg/m3, respectively as against 0.30 kg/m3 recorded in farmers practice. Polythene mulch with drip irrigation at 2-day irrigation interval is recommended for improving the yields and water productivity of chickpea cultivated under eastern plateau and hill region of India.

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Atmometer – based irrigation scheduling system for drip – irrigated onion (Allium cepa L.)

MATEC Web of Conferences ◽

10.1051/matecconf/201819203039 ◽

2018 ◽

Vol 192 ◽

pp. 03039

Author(s):

Cresan Joy Villaroman ◽

Armando Espino ◽

Jeffrey Lavarias ◽

Victorino Taylan

Keyword(s):

Crop Production ◽

Water Productivity ◽

Irrigation Scheduling ◽

Crop Water ◽

San Jose ◽

Scheduling System ◽

Irrigation Interval ◽

Randomized Design ◽

Allium Cepa L ◽

Monteith Equation

This study was conducted to develop an atmometer-based irrigation scheduling system for drip-irrigated onion production. The study was conducted at San Agustin, San Jose City Nueva Ecija from November 2016 – March 2017. Three treatments composing of three replicates were considered in the research. Treatments 1 and 2 were based on the recorded atmometer readings with an irrigation interval of two days and five days respectively. Treatment 3 is a soil moisture-based irrigation scheduling with a management allowed deficit of 50 %. Calibration curved was obtained by comparing the atmometer readings with the estimated evapotranspiration using Modified Penman-Monteith equation. It was used in computing the crop water requirement for Treatments 1 and 2. The important parameters that used to answer the objective of the study such as plant height, crop yield, bulb weight, bulb diameter, water use and water productivity, were acquired during and after crop production. The statistical analysis used in the study was Analysis of Variance for Complete Randomized Design and paired T-test. Based on the result, Treatment 1 was highly useful in increasing water productivity without sacrificing the crop qualities.

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Effects of irrigation scheduling and different irrigation methods on onion and water productivity in Tigray, northern Ethiopia

10.1101/790105 ◽

2019 ◽

Author(s):

Gebremedhin Gebremeskel Haile ◽

T.G. Gebremicael ◽

Mulubrehan Kifle ◽

Teferi Gebremedhin

Keyword(s):

Water Resources ◽

Irrigation Water ◽

Water Productivity ◽

Irrigation Scheduling ◽

Fixed Interval ◽

Northern Ethiopia ◽

Irrigation Method ◽

Irrigation Methods ◽

Irrigation Interval ◽

Basin Irrigation

AbstractEfficient irrigation water use can meet its objective if irrigated agriculture is managed properly in regions where water is limited. A two-year (2016-2017) field experiments were conducted in the semiarid areas of Tigray in northern Ethiopia to evaluate irrigation scheduling with different irrigation methods. The experiments were carried out to identify their contribution for enhancing onion and water productivity in water-stressed irrigation schemes of Korir and Hatset sites. Six factorial treatments comprising of three levels of irrigation methods (furrow, basin and flood) and two levels of irrigation scheduling (fixed interval and farmer’s practices) were evaluated with three replications. The agronomic and irrigation parameters were subjected to separate level-wise comparison followed by the factorial interaction effects. The results showed that the fixed irrigation interval, basin irrigation method and their factorial combinations showed better performances and produced a higher yield and water productivity. On average, 263.85 q/ha and 281 q/ha of onion were obtained under the basin irrigation method and basin irrigation with fixed irrigation interval (T2) at both sites and seasons. For the T2, 6.27 and 6.06 kg/m3 of water productivity (WP) and 4.39 and 4.24 kg/m3 of irrigation water productivity (IWP) were obtained at Korir and Hatset sites, respectively showing higher results as compared to other treatment combinations. Moreover, the basin irrigation method produces higher marketable onion bulbs that are essential for onion producers to earn maximum profit from selling and enhance their livelihoods. Treatments comprising basin method and fixed interval showed better onion and water productivity in the water-limited irrigation schemes of Tigray. Hence, focusing on enhanced irrigation scheduling techniques and irrigation methods are important for effective agricultural water management. Farmers, irrigation experts, water resources managers and decision-makers are suggested to use these techniques to save the limited water resources and increase agricultural productivity.

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Using High-Spatiotemporal Thermal Satellite ET Retrievals for Operational Water Use and Stress Monitoring in a California Vineyard

Remote Sensing ◽

10.3390/rs11182124 ◽

2019 ◽

Vol 11 (18) ◽

pp. 2124 ◽

Cited By ~ 5

Author(s):

Knipper ◽

Kustas ◽

Anderson ◽

Alsina ◽

Hain ◽

...

Keyword(s):

Data Fusion ◽

Water Use ◽

Deficit Irrigation ◽

Irrigation Management ◽

Growing Season ◽

Irrigation Scheduling ◽

Data Availability ◽

Sensor Data ◽

Water Requirements ◽

Fusion Approach

In viticulture, deficit irrigation strategies are often implemented to control vine canopy growth and to impose stress at critical stages of vine growth to improve wine grape quality. To support deficit irrigation scheduling, remote sensing technologies can be employed in the mapping of evapotranspiration (ET) at the field to sub-field scales, quantifying time-varying vineyard water requirements and actual water use. In the current study, we investigate the utility of ET maps derived from thermal infrared satellite imagery over a vineyard in the Central Valley of California equipped with a variable rate drip irrigation (VRDI) system which enables differential water applications at the 30 × 30 m scale. To support irrigation management at that scale, we utilized a thermal-based multi-sensor data fusion approach to generate weekly total actual ET (ETa) estimates at 30 m spatial resolution, coinciding with the resolution of the Landsat reflectance bands. Crop water requirements (ETc) were defined with a vegetative index (VI)-based approach. To test capacity to capture stress signals, the vineyard was sub-divided into four blocks with different irrigation management strategies and goals, inducing varying degrees of stress during the growing season. Results indicate derived weekly total ET from the thermal-based data fusion approach match well with observations. The thermal-based method was also able to capture the spatial heterogeneity in ET over the vineyard due to a water stress event imposed on two of the four vineyard blocks. This transient stress event was not reflected in the VI-based ETc estimate, highlighting the value of thermal band imaging. While the data fusion system provided valuable information, latency in current satellite data availability, particularly from Landsat, impacts operational applications over the course of a growing season.

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Assessment of ET-HS Model for Estimating Crop Water Demand and Its Effects on Yield and Yield Components of Barley and Wheat in Semi-Arid Region of Iran

Cercetari Agronomice in Moldova ◽

10.1515/cerce-2017-0034 ◽

2017 ◽

Vol 50 (4) ◽

pp. 37-49

Author(s):

A. Soleymani ◽

M.H. Shahrajabian

Keyword(s):

Grain Yield ◽

Water Demand ◽

Harvest Index ◽

Irrigation Schedule ◽

Irrigation Treatment ◽

Growing Season ◽

Control Treatment ◽

Crop Water ◽

Crop Water Demand ◽

Biological Yield

Abstract In order to estimate the water requirement of barley and wheat by using of ET-HS model, a research was conducted at Research Farm of Islamic Azad University, Isfahan (Khorasgan) Branch, Iran. ET-HS model is used to determine irrigation water quantity and irrigation schedule for different crop. The study was based on randomized complete block design (RCBD) with three replications and six treatments. The irrigation treatments included irrigation to supply 50, 75, 100, 125 and 150% of crop water demand on the basis of ET-HS model during growing season and control treatment (conventional irrigation), which was irrigation on the basis of 70 mm evaporation from Class A evaporation pan during growing season. In barley experiment, the highest values for number of fertile tiller, maximum LAI, total dry matter in maximum LAI stage, number of grain per spike, a thousand seed weight (35.56 g), grain yield (7877.9 kg/ha), biological yield (17689.7 kg/ha) and harvest index (44.45%) was obtained for irrigation according to 100% of crop water demand on the basis of ET-HS model. In wheat experiment, the highest number of fertile spike, number of grain per spike, 1000 grain weight, grain yield, biological yield was obtained for irrigation treatment on the basis of 100% ET-HS model; moreover, the maximum harvest index was related to control treatment, followed by irrigation on the basis of 100% of ET-HS model. Conclusively, the appropriate irrigation treatment was 100% of crop water demand on the basis of ET-HS model during the growth season for both crops.

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Forty Years of Increasing Cotton’s Water Productivity and Why the Trend Will Continue

Applied Engineering in Agriculture ◽

10.13031/aea.13911 ◽

2020 ◽

Vol 36 (4) ◽

pp. 457-478

Author(s):

Edward M Barnes ◽

B. Todd Campbell ◽

George Vellidis ◽

Wesley Porter ◽

Jose Payero ◽

...

Keyword(s):

United States ◽

Water Use ◽

Irrigation Water ◽

Water Productivity ◽

The United States ◽

Irrigation Scheduling ◽

Crop Water ◽

Water Requirements ◽

Crop Water Productivity ◽

The U.S

Highlights Over the last 40 years the amount of irrigation water used by cotton in the United States has decreased while yields have increased leading to a large increase in crop water productivity (CWP). Many factors have contributed to improved CWP, such as improvements in water delivery systems. Irrigation scheduling technologies have also contributed to improved CWP; however, farmer adoption of advanced scheduling technologies is still limited and there is significant room for improvement. Increased yields from improved cultivars without an increase in water requirements has also been important for CWP. Continued developments in sensor technologies and improved crop simulation models are two examples of future strategies that should allow the U.S. cotton industry to continue an upward trend in CWP. Abstract. Over the last 40 years the amount of irrigation water used by cotton in the United States has decreased while yields have increased. Factors contributing to higher water productivity and decreased irrigation water use include migration of cotton out of the far western U.S. states to the east where more water requirements are met by rainfall; improved irrigation delivery systems with considerable variation in types and adoption rates across the U.S.; improved irrigation scheduling tools; improved genetics and knowledge of cotton physiology, and improved crop models that can help evaluate new irrigation strategies rapidly and inexpensively. The considerable progress over the last 40 years along with the promise of emerging technologies suggest that this progress will continue. Keywords: Cotton, Crop water productivity, Irrigation, Sustainability, Water use efficiency.

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Irrigation Management of Potatoes Using Sensor Feedback: Texas High Plains

Transactions of the ASABE ◽

10.13031/trans.13925 ◽

2020 ◽

Vol 63 (5) ◽

pp. 1259-1276

Author(s):

Susan A. O’Shaughnessy ◽

Manuel A. Andrade ◽

Paul D. Colaizzi ◽

Fekede Workneh ◽

Charles M. Rush ◽

...

Keyword(s):

Soil Water ◽

Control Method ◽

Potato Crop ◽

Water Productivity ◽

Irrigation Management ◽

Field Capacity ◽

Growing Season ◽

Irrigation Scheduling ◽

Manual Control ◽

Water Sensing

HighlightsPotatoes irrigated at 80% and 100% replenishment of soil water depletion to field capacity resulted in statistically similar tuber yields and irrigation water productivity.In the drier growing season, irrigation scheduling using sensor feedback resulted in fewer irrigations compared with the manual-control method.In the wetter growing season, irrigation scheduling using sensor feedback resulted in similar or better tuber yields compared with the manual-control method.Abstract. Few studies have investigated yield and crop water productivity of plant and soil water sensing feedback systems for site-specific irrigation management of a potato crop. In this two-year study (2018 and 2019), the irrigation scheduling supervisory control and data acquisition (ISSCADA) system developed by scientists at the USDA-ARS Conservation and Production Research Laboratory in Bushland, Texas, was used to manage a potato crop at three irrigation levels. The ISSCADA system used two different irrigation scheduling methods: (1) plant feedback and (2) a hybrid method that combines plant feedback with soil water sensing with a soil water depletion (SWD) threshold initially set at 50% and reduced to 35% in the second year. Tuber yield, crop water productivity (CWP), and irrigation water productivity (IWP) resulting from the two ISSCADA irrigation scheduling methods were compared with a manual-control method based on weekly neutron probe readings. The irrigation levels were 100%, 80%, and 60% (I100, I80, and I60) of full and were accomplished by either replenishment of SWD to field capacity or by the equivalent plant feedback or SWD thresholds of the ISSCADA system. In the second study year, the SWD threshold was reduced to 35%. Cumulative irrigation amounts for the ISSCADA treatment methods were significantly less compared with the manual-control method in the I100 levels for both years. This resulted in significantly smaller tuber yields and CWP in the first year of the study, a hot dry growing season. In the second year of the study, tuber yields and CWP were similar between irrigation scheduling methods, and IWP was significantly greater for the ISSCADA-plant feedback method. Considering the effect of irrigation treatment, the tuber yields, CWP, and IWP between the I100 and I80 levels were similar in both years, resulting in an average savings of 85 mm at the I80 level. Future studies are needed to investigate if the change in the SWD threshold could enable the ISSCADA-hybrid system to adjust to variable climatic conditions and successfully irrigate potatoes in this region. Keywords: Center pivot, Dynamic prescription maps, Plant feedback, Site-specific variable-rate irrigation, Soil water sensing feedback, Wireless sensor networks

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WATER STRESS EFFECT ON WHEAT AT DIFFERENT MECHANICAL SEEDING SYSTEMS

Cercetari Agronomice in Moldova ◽

10.46909/cerce-2019-0021 ◽

2019 ◽

Vol 52 (3) ◽

pp. 207-219

Author(s):

Rokon Zaman

Keyword(s):

Water Use ◽

Conservation Tillage ◽

Water Productivity ◽

Irrigation Schedule ◽

Irrigation Treatment ◽

Grain Filling ◽

Irrigation Scheduling ◽

Stress Effect ◽

Wheat Cultivation ◽

Strip Tillage

Judicial water use, as well as improving water use efficiency in agriculture is new challenge. Conservation tillage, as well as mechanical seeding system, offers various benefits over intensive tillage system. Considering this, the study was conducted to find out the water requirements and appropriate deficit irrigation schedule of wheat on different seeding system. This study consisted of following irrigation treatments, like I1 = Irrigation at CRI stage, I2 = Irrigation at CRI and vegetative stages, I3 = Irrigation at CRI and grain filling stages and I4 = Irrigation at CRI, vegetative and grain filling stages on four mechanical seeding methods, like T1 = Bed planting, T2 = PTOS, T3 = Strip tillage, and T4 = Zero tillage and laid out in a split plot design with three replications. From the result based on the grain yield and water productivity, bed planting (T1) and three levels of irrigation (I4) was found as the best combination for wheat cultivation. Besides, at water scarcity area bed planting (T1), with two irrigation I2 (CRI and vegetative) was the suitable reduce irrigation scheduling for wheat cultivation. In different seeding methods, bed planting was increased yield about 10.58%, followed by PTOS and yield was identical in PTOS and ST. Comparatively, lowest yield was observed in zero. In irrigation treatment, three irrigations (I4) was observed, the best scheduling for wheat on all seeding system and yield was increased 11.98% in I4, followed by I2 and lowest yield was found in I1. The result also revealed that the soil moisture contribution was decreased with increased applied water, as well as number of irrigation.

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Irrigation Scheduling with Soil Gas Diffusivity as a Decision Tool to Mitigate N2O Emissions from a Urine-Affected Pasture

Agriculture ◽

10.3390/agriculture11050443 ◽

2021 ◽

Vol 11 (5) ◽

pp. 443

Author(s):

Camille Rousset ◽

Timothy J. Clough ◽

Peter R. Grace ◽

David W. Rowlings ◽

Clemens Scheer

Keyword(s):

Irrigation Management ◽

Irrigation Treatment ◽

Irrigation Scheduling ◽

Soil Gas ◽

N2o Emissions ◽

Irrigation Frequency ◽

Water Demands ◽

Gas Diffusivity ◽

Matter Production ◽

Access To Water

Pastures require year-round access to water and in some locations rely on irrigation during dry periods. Currently, there is a dearth of knowledge about the potential for using irrigation to mitigate N2O emissions. This study aimed to mitigate N2O losses from intensely managed pastures by adjusting irrigation frequency using soil gas diffusivity (Dp/Do) thresholds. Two irrigation regimes were compared; a standard irrigation treatment based on farmer practice (15 mm applied every 3 days) versus an optimised irrigation treatment where irrigation was applied when soil Dp/Do was ≈0.033 (equivalent to 50% of plant available water). Cow urine was applied at a rate of 700 kg N ha−1 to simulate a ruminant urine deposition event. In addition to N2O fluxes, soil moisture content was monitored hourly, Dp/Do was modelled, and pasture dry matter production was measured. Standard irrigation practices resulted in higher (p = 0.09) cumulative N2O emissions than the optimised irrigation treatment. Pasture growth rates under treatments did not differ. Denitrification during re-wetting events (irrigation and rain) contributed to soil N2O emissions. These results warrant further modelling of irrigation management as a mitigation option for N2O emissions from pasture soils, based on Dp/Do thresholds, rainfall, plant water demands and evapotranspiration.

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Combined simulation and optimization framework for irrigation scheduling in agriculture fields

Irrigation Science ◽

10.1007/s00271-021-00746-y ◽

2021 ◽

Author(s):

Mireia Fontanet ◽

Daniel Fernàndez-Garcia ◽

Gema Rodrigo ◽

Francesc Ferrer ◽

Josep Maria Villar

Keyword(s):

Crop Yields ◽

Root Zone ◽

Growing Season ◽

Irrigation Scheduling ◽

Irrigated Agriculture ◽

Traditional Methods ◽

Simulation And Optimization ◽

Optimization Framework ◽

Net Margin ◽

Combined Simulation

AbstractIn the context of growing evidence of climate change and the fact that agriculture uses about 70% of all the water available for irrigation in semi-arid areas, there is an increasing probability of water scarcity scenarios. Water irrigation optimization is, therefore, one of the main goals of researchers and stakeholders involved in irrigated agriculture. Irrigation scheduling is often conducted based on simple water requirement calculations without accounting for the strong link between water movement in the root zone, soil–water–crop productivity and irrigation expenses. In this work, we present a combined simulation and optimization framework aimed at estimating irrigation parameters that maximize the crop net margin. The simulation component couples the movement of water in a variably saturated porous media driven by irrigation with crop water uptake and crop yields. The optimization component assures maximum gain with minimum cost of crop production during a growing season. An application of the method demonstrates that an optimal solution exists and substantially differs from traditional methods. In contrast to traditional methods, results show that the optimal irrigation scheduling solution prevents water logging and provides a more constant value of water content during the entire growing season within the root zone. As a result, in this case, the crop net margin cost exhibits a substantial increase with respect to the traditional method. The optimal irrigation scheduling solution is also shown to strongly depend on the particular soil hydraulic properties of the given field site.

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