scholarly journals Calibration, validation and application of AquaCrop model in irrigation scheduling for rice under northwest India

2015 ◽  
Vol 7 (2) ◽  
pp. 691-699 ◽  
Author(s):  
S. S. Sandhu ◽  
S. S. Mahal ◽  
Prabhjyot Kaur
Keyword(s):  
Grain Yield ◽  
Field Experiments ◽  
Water Productivity ◽  
Irrigation Schedule ◽  
Research Work ◽  
Simulation Models ◽  
Irrigation Scheduling ◽  
Loamy Sand Soil ◽  
Aquacrop Model ◽  
Dry Biomass

A lot of research work regarding irrigation scheduling in rice has been carried out at global level with the objective of increasing irrigation water productivity (IWP) and sustaining grain yield. Under natural conditions rain disturb the planned irrigation treatments. One way to overcome this problem is to use rain shelters which is a costly affair, crop growth simulation models offer a good scope to conduct such studies by excluding the effect of rain. Very limited studies are available where FAO’s AquaCrop model has been used to develop irrigation schedule for crops. Therefore, a study was conducted using FAO AquaCrop model to develop irrigation schedule for rice having higher IWP. The model was calibrated and validated using the experimental data of field experiments conducting during 2009 and 2010, respectively. The model underestimated the above ground dry biomass at 30 days after transplanting (DAT) in the range of 21.60 to 24.85 %. At the time of harvest the model overestimated the above ground dry biomass within the range 11.58 to 14.34 %. At harvest the values of normalized root mean square error (15.54%) suggested a good fit for the above ground dry biomass and an excellent agreement (3.34%) between observed and model predicted grain yield. The model suggested to irrigate rice transplanted in puddled loamy sand soil on every 5th day to get higher IWP coupled with statistically similar grain yield as obtained with daily irrigation schedule.

scholarly journals IRRIGATION OF CHICKPEA (CICER ARIETINUM L.) INCREASES YIELD BUT NOT WATER PRODUCTIVITY

2015 ◽  
Vol 52 (1) ◽  
pp. 1-13 ◽  
Author(s):  
GURIQBAL SINGH ◽  
HARI RAM ◽  
NAVNEET AGGARWAL ◽  
NEIL C. TURNER
Keyword(s):  
Grain Yield ◽  
Cicer Arietinum ◽  
Field Experiments ◽  
Water Productivity ◽  
High Water ◽  
Loamy Sand ◽  
First Year ◽  
World Population ◽  
Sand Soil ◽  
Loamy Sand Soil

SUMMARYThe depth to ground water is increasing in several regions of the world due to use of high-yielding, but also high water-requiring crops such as rice (Oryza sativa) and wheat (Triticum aestivum), in order to maintain food security for an ever increasing world population. There is a need not only to increase the water productivity of food crops, but also to find less water-requiring crops. Irrigated chickpea (Cicer arietinum L.), traditionally grown without irrigation, may provide an alternative crop to irrigated wheat in some regions. Two field experiments were conducted to determine the effects of irrigation on chickpea yields, yield components and grain and biomass water productivity (based on irrigation (WPI) and irrigation + rainfall (WPI+R)) grown in a loamy sand soil. In the first year, 75 mm of irrigation at the vegetative stage and at the vegetative plus podding stages resulted in a 59% and a 73% increase in grain yield, respectively, compared to no irrigation, but with little change in WPI+R. Overall yields in the second year were significantly higher due to warmer temperatures and fewer frosts during flowering and podding. Compared to no irrigation, 75 mm of irrigation at flowering or at podding resulted in a 7% and a 27% increase in grain yield, but a decrease in grain and biomass water productivity (WPI+R). Irrigation had a significant effect on the number of pods plant−1 in both the years and on 100-seed weight in the first year. We conclude that application of a single irrigation during podding to chickpea grown in a loamy sand soil will reliably increase yields and may provide a water-saving alternative to wheat in water-scarce environments.

scholarly journals Validation of DRAS model for irrigation of wheat

1970 ◽  
Vol 35 (3) ◽  
pp. 403-411
Author(s):  
PK Sarkar ◽  
MS Islam ◽  
SK Biswas ◽  
MA Hossain ◽  
S Hassan
Keyword(s):  
Field Experiments ◽  
Water Productivity ◽  
Irrigation Schedule ◽  
Wheat Variety ◽  
Model Performance ◽  
Irrigation Scheduling ◽  
Ecological Zone ◽  
Drought Assessment ◽  
Ecological Zones ◽  
Irrigated Wheat

The study was conducted to validate the Drought Assessment (DRAS) model developed by the Center for Environmental and Geographic Information Services (CEGIS) for irrigation scheduling of wheat (variety: Shatabdi). The performance of the model was compared with the results obtained from the BARI recommended irrigation schedule. The field experiments were carried out during the years 2005-2006 through 2007-2008 in two agro-ecological zones. The locations were RARS, Jamalpur under agro-ecological zone 9 and farmers’ field of FSR site, OFRD, Barind, Rajshahi under agro-ecological zone 26. Six different irrigation treatments including one rainfed with three replications were considered for the study. In respect of yield, BARI recommended irrigation practice performed better in Jamalpur (3.642 t/ha on average). Application of net irrigation requirement (NIR) as per DRAS model based on reported value yielded highest (3.598 t/ha on average) in the Barind area, Rajshahi. However, the yields from all irrigated treatments were very close to each other. From three years’ study, the model performance was found quite satisfactory for irrigated wheat, especially in drought prone areas like Barind, Rajshahi. In respect of water productivity, the model performed almost similar to the BARI recommended practice in Jamalpur. It performed better in Barind region where irrigation water was used by the crop more efficiently. Keywords: DRAS model; irrigation; wheat. DOI: 10.3329/bjar.v35i3.6447Bangladesh J. Agril. Res. 35(3) : 403-411

Effect of herbicides on the weed infestation and grain yield of soybean (Glycine max)

2004 ◽  
Vol 52 (2) ◽  
pp. 199-203 ◽  
Author(s):  
G. Singh ◽  
R. S. Jolly
Keyword(s):  
Glycine Max ◽  
Grain Yield ◽  
Weed Control ◽  
Negative Correlation ◽  
Rainy Season ◽  
Dry Matter ◽  
Field Experiments ◽  
Sand Soil ◽  
Loamy Sand Soil ◽  
Weed Infestation

Two field experiments were conducted during the kharif (rainy) season of 1999 and 2000 on a loamy sand soil to study the effect of various pre- and post-emergence herbicides on the weed infestation and grain yield of soybean. The presence of weeds in the weedy control plots resulted in 58.8 and 58.1% reduction in the grain yield in the two years compared to two hand weedings (HW) at 30 and 45 days after sowing (DAS), which gave grain yields of 1326 and 2029 kg ha-1. None of the herbicides was significantly superior to the two hand weedings treatment in influencing the grain yield. However, the pre-emergence application of 0.75 kg ha-1 S-metolachlor, and 0.5 kg ha-1 pendimethalin (pre-emergence) + HW 30 DAS were at par or numerically superior to this treatment. There was a good negative correlation between the weed dry matter at harvest and the grain yield of soybean, which showed that effective weed control is necessary for obtaining higher yields of soybean.

scholarly journals A semi-quantitative approach for modelling crop response to soil fertility: evaluation of the AquaCrop procedure

2014 ◽  
Vol 153 (7) ◽  
pp. 1218-1233 ◽  
Author(s):  
H. VAN GAELEN ◽  
A. TSEGAY ◽  
N. DELBECQUE ◽  
N. SHRESTHA ◽  
M. GARCIA ◽  
...  
Keyword(s):  
Soil Fertility ◽  
Grain Yield ◽  
Soil Water ◽  
Crop Production ◽  
Water Productivity ◽  
Canopy Cover ◽  
Quantitative Approach ◽  
Fertility Level ◽  
Crop Response ◽  
Aquacrop Model

SUMMARYMost crop models make use of a nutrient-balance approach for modelling crop response to soil fertility. To counter the vast input data requirements that are typical of these models, the crop water productivity model AquaCrop adopts a semi-quantitative approach. Instead of providing nutrient levels, users of the model provide the soil fertility level as a model input. This level is expressed in terms of the expected impact on crop biomass production, which can be observed in the field or obtained from statistics of agricultural production. The present study is the first to describe extensively, and to calibrate and evaluate, the semi-quantitative approach of the AquaCrop model, which simulates the effect of soil fertility stress on crop production as a combination of slower canopy expansion, reduced maximum canopy cover, early decline in canopy cover and lower biomass water productivity. AquaCrop's fertility response algorithms are evaluated here against field experiments with tef (Eragrostis tef (Zucc.) Trotter) in Ethiopia, with maize (Zea mays L.) and wheat (Triticum aestivum L.) in Nepal, and with quinoa (Chenopodium quinoa Willd.) in Bolivia. It is demonstrated that AquaCrop is able to simulate the soil water content in the root zone, and the crop's canopy development, dry above-ground biomass development, final biomass and grain yield, under different soil fertility levels, for all four crops. Under combined soil water stress and soil fertility stress, the model predicts final grain yield with a relative root-mean-square error of only 11–13% for maize, wheat and quinoa, and 34% for tef. The present study shows that the semi-quantitative soil fertility approach of the AquaCrop model performs well and that the model can be applied, after case-specific calibration, to the simulation of crop production under different levels of soil fertility stress for various environmental conditions, without requiring detailed field observations on soil nutrient content.

CALIBRATION AND VALIDATION OF FAO-AQUACROP MODEL FOR IRRIGATED AND WATER DEFICIENT BAMBARA GROUNDNUT

2011 ◽  
Vol 47 (3) ◽  
pp. 509-527 ◽  
Author(s):  
A. S. KARUNARATNE ◽  
S. N. AZAM-ALI ◽  
G. IZZI ◽  
P. STEDUTO
Keyword(s):  
Field Experiments ◽  
Water Productivity ◽  
Canopy Cover ◽  
Research Unit ◽  
Bambara Groundnut ◽  
Women Farmers ◽  
Sub Saharan Africa ◽  
Yield Response ◽  
Grain Legume ◽  
Aquacrop Model

SUMMARYSimulation of yield response to water plays an increasingly important role in optimization of crop water productivity (WP) especially in prevalent drought in Africa. The present study is focused on a representative crop: bambara groundnut (Vigna subterranea), an ancient grain legume grown, cooked, processed and traded mainly by subsistence women farmers in sub-Saharan Africa. Over four years (2002, 2006–2008), glasshouse experiments were conducted at the Tropical Crops Research Unit, University of Nottingham, UK under controlled environments with different landraces, temperatures (23 ± 5 °C, 28 ± 5 °C, 33 ± 5 °C) and soil moisture regimes (irrigated, early drought, late drought). Parallel to this, field experiments were conducted in Swaziland (2002/2003) and Botswana (2007/2008). Crop measurements of canopy cover (CC), biomass (B) and pod yield (Y) of selected experiments from glasshouse (2006 and 2007) and field (Botswana) were used to calibrate the FAO AquaCrop model. Subsequently, the model was validated against independent data sets from glasshouse (2002 and 2008) and field (Swaziland) for different landraces. AquaCrop simulations for CC, B and Y of different bambara groundnut landraces are in good agreement with observed data with R2 (CC-0.88; B-0.78; Y-0.72), but with significant underestimation for some landraces.

scholarly journals Evapotranspiration Partition and Dual Crop Coefficients in Apple Orchard with Dwarf Stocks and Dense Planting in Arid Region, Aksu Oasis, Southern Xinjiang

Agriculture ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1167
Author(s):  
Hui Cao ◽  
Hongbo Wang ◽  
Yong Li ◽  
Abdoul Kader Mounkaila Hamani ◽  
Nan Zhang ◽  
...  
Keyword(s):  
Water Management ◽  
Water Productivity ◽  
Irrigation Schedule ◽  
Irrigation Scheduling ◽  
Apple Orchard ◽  
Irrigation Amount ◽  
Late Season ◽  
Apple Production ◽  
Crop Coefficients ◽  
Southern Xinjiang

Crop coefficients are critical to developing irrigation scheduling and improving agricultural water management in farmland ecosystems. Interest in dwarf cultivation with high density (DCHD) for apple production increases in Aksu oasis, southern Xinjiang. The lack of micro-irrigation scheduling limits apple yield and water productivity of the DCHD-cultivated orchard. A two-year experiment with the DCHD-cultivated apple (Malus × domestica ‘Royal Gala’) orchard was conducted to determine crop coefficients and evapotranspiration (ETa) with the SIMDualKc model, and to investigate apple yield and water productivity (WP) in response to different irrigation scheduling. The five levels of irrigation rate were designed as W1 of 13.5 mm, W2 of 18.0 mm, W3 of 22.5 mm, W4 of 27.0 mm, and W5 of 31.5 mm. The mean value of basal crop coefficient (Kcb) at the initial-, mid-, and late-season was 1.00, 1.30, and 0.89, respectively. The Kc-local (ETa/ET0) range for apple orchard with DCHD was 1.11–1.20, 1.33–1.43, and 1.09–1.22 at the initial, middle, and late season, respectively. ETa of apple orchard in this study ranged between 415.55–989.71 mm, and soil evaporation accounted for 13.85–29.97% of ETa. Relationships between total irrigation amount and apple yield and WP were developed, and W3 was suggested as an optimum irrigation schedule with an average apple yield of 30,540.8 kg/ha and WP of 4.45 kg/m3 in 2019–2020. The results have implications in developing irrigation schedules and improving water management for apple production in arid regions.

scholarly journals Optimization of Irrigation Scheduling for Maize in an Arid Oasis Based on Simulation–Optimization Model

Agronomy ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 935 ◽  
Author(s):  
Jiang Li ◽  
Xiyun Jiao ◽  
Hongzhe Jiang ◽  
Jian Song ◽  
Lina Chen
Keyword(s):  
Simulation Model ◽  
Optimization Model ◽  
Simulation Optimization ◽  
Water Productivity ◽  
Irrigation Schedule ◽  
Irrigation Scheduling ◽  
Water Saving ◽  
Scheduling Optimization ◽  
Agricultural Water Resources ◽  
Crop Water Consumption

In arid regions, irrigation scheduling optimization is efficient in coping with the shortage of agricultural water resources. This paper developed a simulation–optimization model for irrigation scheduling optimization for the main crop in an arid oasis, aiming to maximize crop yield and minimize crop water consumption. The model integrated the soil water balance simulation model and the optimization model for crop irrigation scheduling. The simulation model was firstly calibrated and validated based on field experiment data for maize in 2012 and 2013, respectively. Then, considering the distribution of soil types and irrigation districts in the study area, the model was used to solve the optimal irrigation schedules for the scenarios of status quo and typical climate years. The results indicated that the model is applicable for reflecting the complexities of simulation–optimization for maize irrigation scheduling. The optimization results showed that the irrigation water-saving potential of the study area was between 97 mm and 240 mm, and the average annual optimal yield of maize was over 7.3 t/ha. The simulation–optimization model of irrigation schedule established in this paper can provide a technical means for the formulation of irrigation schedules to ensure yield optimization and water productivity or water saving.

scholarly journals Effect of Pterocladia capillacea Seaweed Extracts on Growth Parameters and Biochemical Constituents of Jew’s Mallow

Agronomy ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 420 ◽  
Author(s):  
Mohamed Ashour ◽  
Ahmed A. El-Shafei ◽  
Hanan M. Khairy ◽  
Doaa Y. Abd-Elkader ◽  
Mohamed A. Mattar ◽  
...  
Keyword(s):  
Irrigation Water ◽  
Field Experiments ◽  
Growth Parameters ◽  
Water Productivity ◽  
Growth Yield ◽  
Irrigation Scheduling ◽  
Water Extraction ◽  
Yield Response ◽  
Yield Reduction ◽  
Initial Growth

We performed field experiments to evaluate the influence of two extraction treatments, seaweed (Pterocladia capillacea S.G. Gmelin) water extraction (WE) and ultrasound-assisted water extraction (USWE) at three concentrations (5%, 10%, and 15%), as well as control NPK traditional mineral fertilizer on the growth, yield, minerals, and antioxidants of Jew’s Mallow (Corchorus olitorius L.) during the two seasons of 2016 and 2017 in Egypt. Plant height, number of leaves, and fresh weight of WE10 treatment were the highest (p < 0.05) as 59.67 cm, 10.67 and 2.41 kg m−2 in 2016, respectively, and 57.33 cm, 11.00 and 2.32 kg m−2 in 2017, respectively. WE10 and USWE5 treatments produced the highest dry matter (17.07%) in 2016 and (16.97%) in 2017, respectively. WE10 plants had an increased water productivity of 41.2% relative to control plants in both seasons. The highest chlorophyll ‘a’ was recorded after the WE10 treatment in 2016 and 2017 (17.79 μg g−1 and 17.84 μg g−1, respectively). The highest levels of total antioxidant capacity, total phenolics, and total flavonoids were also recorded after the WE10 treatment. Application of WE10 boosted growth, yield, minerals, and antioxidants of Jew’s Mallow. The CROPWAT model was used to estimate the evapotranspiration, irrigation water requirements, and yield response to irrigation scheduling. Our data showed a yield reduction in the initial growth stage if a limited amount of water was provided. Therefore, irrigation water should be provided during the most important stages of crop development with the choice of effective irrigation practices to avoid water losses, as this helps to maximize yield.

scholarly journals Integrated Effect of Plant Density, N Rates and Irrigation Regimes on the Biomass Production, N Content, PAR Use Efficiencies and Water Productivity of Rice Under Irrigated Semiarid Environment

2012 ◽  
Vol 40 (1) ◽  
pp. 201 ◽  
Author(s):  
Shakeel AHMAD ◽  
Mirza HASANUZZAMAN
Keyword(s):  
Grain Yield ◽  
Management Practices ◽  
Field Experiments ◽  
Plant Density ◽  
Block Design ◽  
Water Productivity ◽  
Research Area ◽  
Semiarid Environment ◽  
Irrigation Regimes ◽  
Plant Densities

Two field experiments were conducted for two years (2000 and 2001) at Agronomic Research Area, University of Agriculture Faisalabad (UAF), Pakistan. There were 15 treatment combinations for experiment-I having three plant densities, viz., one seedling hill-1 (PD1), two seedlings hill-1 (PD2) and three seedlings hill-1 (PD3) and five nitrogen rates, viz., 0, (N0); 50, (N50); 100, (N100); 150, (N150); and 200 (N200) kg N ha-1. Experiment-II also included 15 treatments having three plant densities, viz., one seedling hill-1 (PD1), two seedlings hill-1 (PD2) and three seedlings hill-1 (PD3) and five irrigation regimes, viz., 62.5 cm (I1), 77.5 cm (I2), 92.5 cm (I3), 107.5 cm (I4), and 122.5 cm (I5). A randomized complete block design (RCBD) was employed with three repetitions. The results for experiment-I revealed that the highest biomass (1438 g m-2), grain yield (497 g m-2), crop growth rate (15.36 g m-2 d-1), net assimilation rate (4.24 g m-2 d-1) were observed in the treatment having combination of two seedlings hill-1 and 200 kg N ha-1 (PD2N200). The agronomic and economic nitrogen and PAR use efficiencies were also higher in this treatment. In case of experiment-II, the highest biomass and grain yield were obtained in case of treatment having combination of two seedlings hill-1 and 107.5 cm irrigation regime (PD2I107.5). The irrigation application based water productivity ranged from 0.36 kg mm-3 to 0.61 kg mm-1, irrigation plus precipitation based water productivity ranged from 0.32 kg mm-3 to 0.55 kg mm-3 and evapotranspiration based water productivity ranged from 0.65 kg mm-3 to 0.84 kg mm-3 among 15 treatments combination of plant density and irrigation regimes. This study concludes that for increasing the benefits for the resource-poor growers, the integration of crop management practices is an optimum strategy to substantially increase the resources use efficiency under irrigated semiarid environment.

scholarly journals Opportunities for improving irrigation efficiency with quantitative models, soil water sensors and wireless technology

2009 ◽  
Vol 148 (1) ◽  
pp. 1-16 ◽  
Author(s):  
D. J. GREENWOOD ◽  
K. ZHANG ◽  
H. W. HILTON ◽  
A. J. THOMPSON
Keyword(s):  
Soil Water ◽  
Field Experiments ◽  
Simulation Models ◽  
Irrigation Scheduling ◽  
Sensor Data ◽  
Urban Landscapes ◽  
Wireless Technology ◽  
Current Review ◽  
Different Depths ◽  
Made In

SUMMARYIncreasingly serious shortages of water make it imperative to improve the efficiency of irrigation in agriculture, horticulture and in the maintenance of urban landscapes. The main aim of the current review is to identify ways of meeting this objective. After reviewing current irrigation practices, discussion is centred on the sensitivity of crops to water deficit, the finding that growth of many crops is unaffected by considerable lowering of soil water content and, on this basis, the creation of improved means of irrigation scheduling. Subsequently, attention is focused on irrigation problems associated with spatial variability in soil water and the often slow infiltration of water into soil, especially the subsoil. As monitoring of soil water is important for estimating irrigation requirements, the attributes of the two main types of soil water sensors and their most appropriate uses are described. Attention is also drawn to the contribution of wireless technology to the transmission of sensor outputs. Rapid progress is being made in transmitting sensor data, obtained from different depths down the soil profile across irrigated areas, to a PC that processes the data and on this basis automatically commands irrigation equipment to deliver amounts of water, according to need, across the field. To help interpret sensor outputs, and for many other reasons, principles of water processes in the soil–plant system are incorporated into simulation models that are calibrated and tested in field experiments. Finally, it is emphasized that the relative importance of the factors discussed in this review to any particular situation varies enormously.

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