The multi-objective genetic algorithm was used as a decision variable to estimate the water required for irrigation in each of the growth stages. Agricultural costs and product sales prices in the agricultural year 2017–2023 in Luoyang Plain and its surrounding areas were collected for this purpose. Optimal irrigation strategies according to different water price scenarios were considered to calculate water use efficiency and net profit. In the conditions of optimal distribution, the amount of allocated water was 7,809, 2,928, 3,904, and 1,789 m3/ha for the stages of vegetative growth, flowering, crop formation, and ripening by the proposed model. On the other hand, it is necessary to reduce water stress in the periods of clustering and seed filling to increase crop yield and net income, as well as to achieve the desired irrigation schedule. Effective rainfall, especially in the ripening stage of the crop, can be considered to determine the optimal volume of water harvesting from the river. In addition, the results showed that by reducing the amount of available water, the water model allocated to leaf greening and tillering stages decreases.

  • A simulation model is calibrated using field data for rice cultivation.

  • The economic value of water adjustments has been measured in different stages of planning.

Rice is a product of temperate and tropical regions, which first spread to China and then to Asia Minor, Europe, and Africa. Rice is the main food of three billion people around the world. A total of 2.2 billion tons of crops are harvested from the 700 million hectares of grain-cultivated land in the world, of which corn, rice, and wheat have the largest share with an annual production of 790, 660, and 600 million tons, respectively (FAO 2012). The total annual production of paddy is around 650–700 million tons, 90% of which is cultivated in Asia. About 40% of freshwater resources in Asia are used to produce more than 90% of the world's rice (FAO 1997; Dawe et al. 1998).

China, India, Japan, Korea, South East Asia, and the neighboring islands of the Pacific Ocean have the largest share of production in the world (Tian et al. 2019). Brazil and the United States are the major non-Asian rice producers with a share of 5% of the world's total consumption. About 75% of the total rice produced in the Asian continent is obtained from low-lying rice fields, which are generally under irrigation with permanent flooding. Water consumption in these paddy fields is estimated to be more than four times that of other grains and nearly 50% of the share of agricultural water in the whole world (Mallareddy et al. 2023).

The common method of farming in the country's paddy fields is to cultivate rice, after preparing the land, seedlings are planted in the main land, and a permanent flood irrigation regime is established in it, which causes the loss of the opportunity to use water (Wudil et al. (2023). On the other hand, this irrigation method is not an unavoidable necessity for the plant with the consumption of a large volume of water and is only a management tool for controlling pests, providing easy access to food, and preventing water stress (Brown et al. 1978; Chandler 1979; McCauley 1990; Arabzadeh & Tavakoli 2014).

Various studies have considered the intermittent or discontinuous flooding regime as a practical solution to save water without significantly reducing crop yield (Ibrahim et al. 1995; Li & Cui 1996; Zou et al. 2021). In this irrigation method, a specific height of water (usually 5 cm) is introduced into the plot, and after the water level reaches zero, the initial height is applied again. Depending on the amount of rainfall in each period, the irrigation intervals will be variable, which increases the productivity of rainfall. Habib et al. (2023) recommended the method of intermittent flood irrigation for rice cultivation in Shiraz without a significant reduction in yield.

Rice has different needs in different growth stages: land preparation, about 1,000–7,000 m3; germination and seed growth in the treasury, 45–60 m3 to prepare the treasury and 75–120 m3 to irrigate the germinated seeds. In the first week after transplanting, the depth of water should be 5–6 cm, and then it should be reduced to 2–3 cm at the time of tillering. In the stage of reproductive growth, constant water depth of 2–4 cm is applied to the plot. Finally, at the stage of ripening, 1–2 cm of water is given to the plant until the plants turn yellow, when the flow is stopped. Rice is sensitive to humidity fluctuations in two periods of growth: the first period after transplanting, when moisture stress can completely destroy the plant, and the second period, 2 weeks before and 1 week after the appearance of the young cluster (stages of cluster formation and flowering). One of the negative effects of flood irrigation is the increase in deep infiltration and as a result the waste of fertilizers, especially nitrogen fertilizer.

Studies show that about 60% of the irrigation water of flooded lands under rice cultivation is out of reach of the crop in the form of deep infiltration or weeds, and in addition to increasing the volume of losses, it causes contamination of the water cycle (Vial 2007; Li et al. 2023). Comparison of the aerobic cultivation system compared to submerged cultivation has shown about 50% water saving in China (Templeton & Bayot 2011). After 1980, in China, a method of irrigation was presented with the aim of saving water consumption in the lands under rice cultivation, which increased the crop yield and prevented pests and water and soil resources. This method of irrigation has been associated with a 50–80% reduction in depth penetration compared with the flooded state. Different methods of increasing rice yield compared with water consumption are as follows: intermittent irrigation, crop cultivation in elevated beds, use of aerobic rice cultivars, and rice production system with ground cover. Several studies have been conducted in the field of reducing water consumption in paddy fields with the aim of investigating periodic irrigation in reducing water consumption and increasing the efficiency of rice water consumption. Champness et al. (2023) in Australia, Arouna et al. (2023) in Ghana, Xie et al. (2023) in China, Mohammed et al. (2023) in Iraq, and Khuong et al. (2023) in Vietnam by comparing different levels of intermittent irrigation and the permanent flooding method showed that by accepting an acceptable percentage of yield reduction, the efficiency of water use can be increased to a large extent.

Intermittent irrigation with water depth and frequency appropriate to the physiology of rice plant growth and its sensitivity to drought stress can lead to an increase in water consumption efficiency. The irrigation water productivity of paddy fields in Iran reported from 0.5 to 1.63 kg/m3 by Lalehzari et al. (2016). In some studies, the efficiency of evaporation and transpiration is estimated at 1.4 (Bouman et al. 2007) and the efficiency of irrigation water in Sri Lanka is estimated at 0.15–1.6 (Molden et al. 2007). According to the report of the International Food Institute, the irrigation water productivity index will increase from 0.39 to 0.53 kg/m3 in developing countries and from 0.47 to 0.57 kg/m3 in developed countries during the years 1995–2025.

Research by Aghajani et al. (2012) at the Shavor Research Station in Iran showed that there was no difference in the yield of rice in two methods of flood and rain irrigation, while the amount of water consumed in the rain system was reduced to one-third to one-fifth of that of flood irrigation. On the other hand, the growth of weeds, the increase of diseases, the small size of the agricultural plots, and the disturbance in the pollination of rice are important obstacles to the development of rainfed methods. Arabzadeh & Tavakoli (2014) investigated the effects of regulated low irrigation in paddy fields and improved water consumption efficiency and achieved proper yield of rice cultivation in the research farm of the Deputy Rice Research Institute of the country. Seven treatments include different levels of low irrigation from permanent flooding of the crop throughout the growth period with a water height of 5 cm (control treatment) to a decrease in humidity to the extent of only creating a saturated state in the soil, and the yield of the crop in these conditions has been analyzed. The results showed that with a 42% reduction in water consumption compared to the control treatment, only 10% reduction in yield per unit of the estimated level is created.

Due to having permanent surface flows and suitable weather conditions (Wu et al. 2022), Luoyang Plain is of interest for rice cultivation, and annually, on average, about 4,500 hectares of land adjacent to the river is used for this purpose. In recent years, with the decrease in rainfall and surface water resources available for rice cultivation, it seems necessary to plan for dry farming and optimal use of limited water resources (Sang et al. 2023). In the present study, by examining the physiological conditions of rice growth and estimating the coefficients of sensitivity to water stress, the planning of water delivery in different conditions to the paddy fields of Luoyang Plain was simulated, and the best patterns of water distribution were analyzed according to the conditions and limitations governing the problem. Evaluating the effect of water pricing on the change in management practices of water allocation is also one of the other goals investigated in this field.

Field experiments

Luoyang is located 34.6181° N, 112.4540° E in Henan province. Luoyang is a city located in the confluence area of the Luo River and the Yellow River in the west of Henan province. Governed as a prefecture-level city, it borders the provincial capital of Zhengzhou to the east, Pingdingshan to the southeast, Nanyang to the south, Sanmenxia to the west, Jiyuan to the north, and Jiaozuo to the northeast.

The Luo River is a tributary of the Yellow River in China. It rises in the southeast flank of Mount Hua in Shaanxi province and flows east into Henan province, where it eventually joins the Yellow River at the city of Gongyi. The river's total length is 420 km. Rice cultivation has a historical history in this area, which was cultivated on a large scale in wet fields using the floodplain of the Luo River.

The length of the crop growth period in the studied area is 120 days from mid-July to mid-November. The treasury and planting operations started in May, and the water used during this period is included in the optimization model as a constant. The reasons for not including seed preparation operations in the form of the optimal water delivery program are as follows: (1) There is no reliable research and specific method for simulating seed production; (2) planting performance or product production at this stage has no real definition and is not subject to price calculation; (3) reservoirs are prepared in very small areas and a specific rule for water consumption in them cannot be determined.

Field operations will be carried out in agricultural lands around Luoyang in Henan provinces, which are uniformly used for rice cultivation. The paddy field is divided into 10 plots with the design shown in Figure 1, and it is controlled and measured in the input and output flow at designated sections. With this structure, after soil saturation at the beginning of the experiment, five levels of programmed irrigation are established based on the actual water requirement of the crop, each with two repetitions (due to the possibility of losing one experiment) during 120 days. The required information of the simulation model that will be explained in the research method will be applied in these plots, and its output results will be used for calibrating and mathematical modeling of rice growth.
Figure 1

Plotting and establishment of flow system for field measurement of experiments.

Figure 1

Plotting and establishment of flow system for field measurement of experiments.

Close modal

If the growth stages of rice based on the Food and Agriculture Organization (FAO) classification are considered, the previous studies and experience showed that rice is sensitive to humidity fluctuations in two periods of growth: the first period after transplanting, when moisture stress can completely destroy the plant, and the second period 2 weeks before and 1 week after the appearance of the young cluster (stages of bunching and flowering), when the effects of lack of moisture are more severe than the first period. Therefore, in the planning model, positive limitations for water supply are considered for these stages, and after modeling, the effects of each will be measured separately.

Modeling process

The main framework of the modeling is shown in Figure 2. In the simulation and optimization section of water delivery to the paddy field, the computer code prepared in MATLAB software is used. Income, costs, performance, and crop irrigation schedule were calculated according to the amount of water received for 10-day periods and optimized to achieve the highest net income in exchange for reducing water consumption. The optimization model was performed using the multi-objective genetic algorithm based on nondominated ranking with the two goals of minimizing water consumption and maximizing the income–cost ratio. The limitations of rice cultivation, including water supply in critical stages of growth, attention to the limitations of water resources cycles, and economic conditions, were added to the developed computer code in the form of mathematical relationships.
Figure 2

Simulation–optimization modeling of rice cultivation.

Figure 2

Simulation–optimization modeling of rice cultivation.

Close modal

The difference between rice cultivation and irrigation planning compared to other products in summary are as follows:

Water supply for the paddy lands of the region is done only through the river. Therefore, it does not participate in the competition for the allocation of permitted withdrawal from underground water. The net income from each hectare of paddy field is far more than other lands, and hence, it accounts for a high percentage of the profitability of a mixed farming model. Due to the importance of the crop for the farmers in the rice growing season, almost no other crop is cultivated and the cultivated area and rice growing season are not included in the same group with any of the plants to optimize target functions. The growth stages of rice are very different from other crops, and plant coefficients and sensitivity, as well as the length of each stage of growth and, as a result, the amount of water it needs, must be planned in a separate submodel.

Considering all these conditions and according to Figure 3, the stages and length of different periods of rice growth were estimated based on the study by FAO (2012), and its coefficients and water requirements were estimated using local, field research, and past studies (Table 1). Potential evapotranspiration during the growing season varies between 3.76 and 9.34 mm/day, respectively, while the average of this parameter is reported from 4.4 mm/day in China to 9.8 mm/day in Vietnam (Tomar & O'Toole 1980). In the paddy fields of West Africa, the water requirement in the stages of transplanting, clustering, and handling was 3.5, 1.7, and 1.4 mm/day, respectively. Plant coefficients were estimated at 0.97, 1.25, and 1.09 in the early, middle, and harvest stages, respectively, and the water requirement was estimated from 1983 to 2361. The water requirement in different weather conditions and different regions from 1,380 m3/ha in China to 16,200 m3/ha in Iran (Yazdani et al. 1990; Hira 1996).
Table 1

Growing coefficients and length for rice cultivation in Luoyang

Water tension coefficient
Growing period (day)
Crop coefficient
Ky1Ky2Ky3Ky4D1D2D3D4C1C2C3
1.09 1.32 0.5 20 30 40 30 1.2 1.35 1.1 
Water tension coefficient
Growing period (day)
Crop coefficient
Ky1Ky2Ky3Ky4D1D2D3D4C1C2C3
1.09 1.32 0.5 20 30 40 30 1.2 1.35 1.1 
Figure 3

Simulation process of rice growth.

Figure 3

Simulation process of rice growth.

Close modal

The review of the current situation shows that the planning of rice water delivery in Luoyang area is done by the flooding method and by harvesting river water. The length of the crop growth period is 120 days from mid-July to mid-November. The operation of preparing treasury and transplanting started from May, and the water used in this period is included in the optimization model as a constant per hectare. The reasons for not including transplant preparation in the form of the optimal water delivery program are as follows: (1) there is no reliable research and specific method for simulating transplant production; (2) planting performance or product production at this stage does not have a real definition and is not included in the price calculation; (3) paddy fields are exploited in areas less than one hectare and a specific rule for water consumption in the region cannot be determined.

After planting and establishment of the crop, irrigation is done daily by creating a water level of 5–10 cm (on average 7 cm). Free agricultural water and no restrictive policies are imposed on users by the water and electricity organization and agricultural jihad for volume delivery or optimal management.

The potential evaporation and transpiration and the water required for rice irrigation were estimated separately for 10-day periods according to Figure 3. The rainfall of November provided part of the water requirement and the difference between the actual water requirement and the potential in the last two periods. The total water requirement of the crop in one season is 16,271 m3/ha, half of which is allocated to the tillering stage of the crop, which is more due to the length of the growth crop (Figure 4). The ripening stage in 20 days with less sensitivity has a lower share of total water.
Figure 4

Irrigation analysis in the rice cultivation period.

Figure 4

Irrigation analysis in the rice cultivation period.

Close modal

Considering the importance of water price in planning the cultivation pattern, different scenarios of the extraction price of each cubic meter of water were defined, and their effects on the production and parameters of rice production and then on the determination of an efficient cultivation pattern of agricultural products were investigated. In the existing conditions, or in other words assuming free water, Table 2 shows the pattern of water allocation to paddy fields in Luoyang. According to the table, by providing a larger fraction of the water requirement of the plant, the yield and as a result its net income will increase with a steeper slope. This issue proves the high sensitivity of rice to dehydration and the necessity of applying an acceptable level of dehydration for optimal use of water. For this reason, the increase in water also increases the efficiency of water consumption. On the other hand, the study of water allocation in growth periods shows that the increase in the share of product water is mainly added to the tillering stage.

Table 2

Evaluation of profit balance based on water price

Water priceProfit per costRelative water supplyRelative yieldNet profitWater productivityWater supplyWater supply in growing periods (%)
USD/m3USDkg/m3103 m31234
0.74 0.44 788 0.18 12.3 24 24 32 10 
2.5 0.8 0.56 986 0.23 13.6 38 22 30 10 
0.85 0.57 1,158 0.25 1.9 40 21 28 11 
3.5 0.9 0.78 13,744 0.28 16.7 42 20 27 11 
0.95 0.89 15,472 0.31 15.5 45 19 25 11 
4.4 1,764 0.34 16.3 48 18 23 11 
0.1 0.83 0.62 983 0.24 13.3 38 22 29 11 
2.5 0.9 0.78 1,285 0.28 14.5 41 20 27 12 
0.98 0.95 1,576 0.31 15.8 46 18 25 11 
3.15 1,682 0.34 16.3 48 18 23 11 
0.25 0.9 0.78 12.2 0.27 14.6 42 20 27 11 
2.44 15.8 0.31 16.3 48 18 23 11 
Water priceProfit per costRelative water supplyRelative yieldNet profitWater productivityWater supplyWater supply in growing periods (%)
USD/m3USDkg/m3103 m31234
0.74 0.44 788 0.18 12.3 24 24 32 10 
2.5 0.8 0.56 986 0.23 13.6 38 22 30 10 
0.85 0.57 1,158 0.25 1.9 40 21 28 11 
3.5 0.9 0.78 13,744 0.28 16.7 42 20 27 11 
0.95 0.89 15,472 0.31 15.5 45 19 25 11 
4.4 1,764 0.34 16.3 48 18 23 11 
0.1 0.83 0.62 983 0.24 13.3 38 22 29 11 
2.5 0.9 0.78 1,285 0.28 14.5 41 20 27 12 
0.98 0.95 1,576 0.31 15.8 46 18 25 11 
3.15 1,682 0.34 16.3 48 18 23 11 
0.25 0.9 0.78 12.2 0.27 14.6 42 20 27 11 
2.44 15.8 0.31 16.3 48 18 23 11 

The most critical stage of water requirement in rice is about 10 days before flowering until flowering, and drought stress in this stage causes the percentage of sterility to increase due to the inability of pollen grains to penetrate the ovary and decrease the seed yield. Water stress in the vegetative stage also causes a decrease in plant height, number of claws, and leaf surface (Cheng et al. 2017).

If the water price per cubic meter of water is considered to be 0.1 USD, the maximum income from rice cultivation per hectare will be 3.15 (Table 2). In this situation, it is necessary to provide 82% of the product's water requirement to reach the minimum profit-to-cost ratio (equal to 2). With the increase of water price to 0.25 USD, obtaining this amount of economic benefit requires 90% of water supply. The complete irrigation of rice with water price of 0, 0.1, and 0.25 USD estimates the net income as 17.5, 16.68, and 15.87, respectively. Another result is that the efficiency of water use has increased with the increase in water prices for a predetermined profit.

Figure 5 shows the amount of water allocation in each 10-day period for different income-to-cost ratios and is compared with potential evaporation and transpiration. According to Figure 5, water reduction is applied only in the tillering and harvesting stages, and the total water requirement of the product is delivered in the clustering and seed filling stages. Rainfall is also the answer to the lack of water at times, but the long-term rainfall statistics in the studied area do not report significant rainfall in the rice growing season, and its effect can be ignored.
Figure 5

Water distribution in different scenarios and different periods of rice crop growth.

Figure 5

Water distribution in different scenarios and different periods of rice crop growth.

Close modal

A look at the condition of the paddy fields of Luoyang and the results obtained from the modeling done in this study show that the use of the dry farming method has the following advantages that can be used as a practical solution to save water consumption: 50% reduction in water consumption from more than 40,000 to less than 20,000 m3 due to the elimination of flooding operations and the use of intermittent irrigation regime; the possibility of using the pressurized (rain) irrigation system; reduction of production cost compared to cultivation; production of more than 5 tons of rice per hectare; the possibility of linear, row, and broadcast cultivation with all kinds of mechanized systems; reducing the cultivation time and increasing the farm capacity to 2 ha/h; creating uniform vegetation on the farm level and respecting planting depth; better control of weeds mechanically and chemically; and use of the periodic system due to the elimination of weeding operations and thus improving the soil structure.

Rice requires an average of 30,000–35,000 m3 of water during its growth period (Yadav & Bhutan 2001). If the plant does not have enough water and humidity during the stage of cluster formation and flowering, the inoculation is not done well and the yield of rice is reduced. Because the low humidity of the pollen grains cannot penetrate into the ovary, the insemination process is not performed correctly and hollow seeds are produced.

The results of the optimization model of Aghajani et al. (2012) showed that the productivity of irrigation water with the same periodic cycle of 7.33 days is calculated as 1.6 kg/m3, while the water distribution in each round of irrigation with a depth of 5.2, 7.3, 6.39, and 6.11 should be done in the stages of establishment, clawing, reproduction, and care, respectively.

The water price of 0.1 USD/m3 will reduce the maximum ratio of income to the cost of paddy cultivation to 3.15. In this situation, to reach the lowest value of this index (equal to 2), it is necessary to supply 82% of the crop's water requirement. With the increase of water price to 0.25 USD, obtaining this amount of economic benefit requires 90% of water supply. The complete irrigation of paddy with water price of 0, 0.1, and 0.25 USD estimates the net income as 17.5, 16.68, and 15.87, respectively. Another result is that the efficiency of water use has increased with the increase in water prices for a predetermined profit. November rainfall provides part of the water requirement of paddy at the end of the growth period, and due to the lower sensitivity of the crop at this stage, this amount of rainfall can be included in the irrigation schedule. The total water requirement of the crop in one season is 16,271 m3/ha, half of which is allocated to the tillering stage of the crop, which is due to the length of the growing season. Also, the economic evaluation of the plan has increased the cultivated area to the highest limit of the allocable area.

All relevant data are included in the paper or its Supplementary Information.

The authors declare there is no conflict.

Aghajani
M.
,
Nawabian
M.
,
Tzafidoost
M.
&
Rezaei
M.
2012
Comparison of simulation models – Optimization of water productivity with fixed and variable irrigation of Hashemi variety rice in Rasht
.
Water Research in Agriculture
27
(
4
),
623
635
.
Arabzadeh
B.
&
Tavakoli
A. R.
2014
The selection of regulated low irrigation management in rice cultivation
.
Journal of Agricultural Sciences and Natural Resources
12
(
4
),
11
20
.
Arouna
A.
,
Dzomeku
I. K.
,
Shaibu
A.-G.
&
Nurudeen
A. R.
2023
Water management for sustainable irrigation in rice (Oryza sativa L.) production: A review
.
Agronomy
13
(
6
),
1522
.
Brown
K. W.
,
Turner
F. T.
,
Tomas
J. C.
,
Deuel
I. E.
&
Keener
M. E.
1978
Water balance of flooded rice paddies
.
Agricultural Water Management
1
,
277
291
.
Champness
M.
,
Vial
L.
,
Ballester
C.
&
Hornbuckle
J.
2023
Evaluating the performance and opportunity cost of a smart-sensed automated irrigation system for water-saving rice cultivation in temperate Australia
.
Agriculture
13
(
4
),
903
.
https://doi.org/10.3390/agriculture13040903
.
Chandler
F. R.
1979
Rice in the Topics: A Guide to the Development of National Programs
.
Westview Press, Boulder, CO, USA
.
Cheng
S. H.
,
Zhuang
J. Y.
,
Fan
Y. Y.
,
Du
J. H.
&
Cao
L. Y.
2017
Progress in research and development on hybrid rice: A super-domesticate in China
.
Annals of Botany
100
(
5
),
959
966
.
Dawe
D.
,
Seckler
D.
&
Barker
R.
1998
Water supply and research for food security in Asia
. In:
Proceeding of the Workshop on Increasing Water Productivity and Efficiency in Rice-Based System
,
Los Banos, Philippines
.
FAO
1997
Irrigation in the Near East Region in figures. FAO Water Report No. 9. Rome, Italy
.
FAO
2012
Crop yield response to water by P. Steduto, T. C. Hsiao, E. Fereres, and D. Raes. FAO Irrigation and Drainage Paper No. 66. Rome, Italy
.
Habib
M. A.
,
Islam
S. M. M.
,
Haque
M. A.
,
Hassan
L.
,
Ali
M. Z.
,
Nayak
S.
,
Dar
M. H.
&
Gaihre
Y. K.
2023
Effects of irrigation regimes and rice varieties on methane emissions and yield of dry season rice in Bangladesh
.
Soil Systems
7
(
2
),
41
.
https://doi.org/10.3390/soilsystems7020041
.
Hira
G. S.
1996
Evapotranspiration of rice and falling water table in Punjab. In Proceedings of International Conference on Evapotranspiration and Irrigation Schedulingheld at Texas, USA (Camp, C. R., Sadler, E. J. & Yoder, R. E., eds). Nov. 3–6. pp. 579–584
.
Ibrahim
M. A. M.
,
El-Gohary
S. A.
,
Willardson
I. S.
&
Sisson
D. V.
1995
Irrigation interval effects on rice production in the Nile Delta
.
Irrigation Science
16
,
29
33
.
Lalehzari, R., Boroomand-Nasab, S., Moazed, H. & Haghighi, A. 2016 Multi-objective management of water allocation to sustainable irrigation planning and optimal cropping pattern. Journal of Irrigation and Drainage Engineering ASCE 142 (1), 05015008.
DOI: 10.1061(ASCE) IR.1943-4774.0000933.
Li
Y. H.
&
Cui
Y. N.
1996
Real time forecasting of irrigation water requirement of paddy fields
.
Agricultural Water Management
31
,
185
193
.
Li
W.
,
Wang
C.
,
Liu
H.
,
Wang
W.
,
Sun
R.
,
Li
M.
&
Fu
S.
2023
Fine root biomass and morphology in a temperate forest are influenced more by canopy water addition than by canopy nitrogen addition
.
Frontiers in Ecology and Evolution
11
, 1132248.
https://doi.org/10.3389/fevo.2023.1132248.
Mallareddy
M.
,
Thirumalaikumar
R.
,
Naseeruddin
R.
,
Nithya
N.
,
Mariadoss
A.
,
Choudhary
A. K.
&
Deiveegan
M.
2023
Maximizing water use efficiency in rice farming: A comprehensive review of innovative irrigation management technologies
.
Water
15
(
10
),
1802
.
https://doi.org/10.3390/w15101802
.
Mohammed
M. K.
,
Hameed
K. A.
&
Musa
A. J.
2023
Water savings, yield, and economic benefits of using SRI methods with deficit irrigation in water-scarce southern Iraq
.
Agronomy
13
(
6
),
1481
.
https://doi.org/10.3390/agronomy13061481
.
Molden
D.
,
Murry-Rust
H.
,
Sakthivandival
R.
&
Makin
I.
2007
A water productivity framework for understanding and action
. In
Workshop on Water Productivity
(Kijne, J. W., Barker, R. & Molden, D., eds).
CABI, Wallingford, UK; International Water Management Institute (IWMI), Colombo, Sri Lanka, pp. 1–18
.
Sang
L.
,
Zhu
G.
,
Xu
Y.
,
Sun
Z.
,
Zhang
Z.
&
Tong
H.
2023
Effects of agricultural large-and medium-sized reservoirs on hydrologic processes in the Arid Shiyang River Basin, Northwest China
.
Water Resources Research
59
(
2
), e2022WR033519.
https://doi.org/10.1029/2022WR033519.
Templeton
D.
&
Bayot
R.
2011
Aerobic rice-responding to water scarcity: An impact assessment of the developing a system of temperate and tropical aerobic rice (STAR) in Asia’ project. CGIAR Challenge Program on Water and Food. Available from: www.waterandfood.org.
Tian
H.
,
Huang
N.
,
Niu
Z.
,
Qin
Y.
,
Pei
J.
&
Wang
J.
2019
Mapping winter crops in China with multi-source satellite imagery and phenology-based algorithm
.
Remote Sensing
11
(
7
),
820
.
https://doi.org/10.3390/rs11070820
.
Tomar
V. S.
&
O'Toole
J. C.
1980
Water use in lowland rice cultivation in Asia: A review of evapotranspiration
.
Agricultural Water Management
3
,
83
106
.
Vial
L. K.
2007
Aerobic and Alternate Wet and Dry (AWD) Rice Systems. Nuffield Australia Publishing, Griffith NSW 2680, Australia
.
Wu
X.
,
Guo
S.
,
Qian
S.
,
Wang
Z.
,
Lai
C.
,
Li
J.
&
Liu
P.
2022
Long-range precipitation forecast based on multipole and preceding fluctuations of sea surface temperature
.
International Journal of Climatology
42
(
15
),
8024
8039
.
https://doi.org/10.1002/joc.7690
.
Wudil
A. H.
,
Ali
A.
,
Mushtaq
K.
,
Baig
S. A.
,
Radulescu
M.
,
Prus
P.
,
Usman
M.
&
Vasa
L.
2023
Water use efficiency and productivity of irrigated rice cultivation in Nigeria: An application of the stochastic frontier approach
.
Sustainability
15
(
10
),
7824
.
https://doi.org/10.3390/su15107824
.
Xie
S.
,
Liu
H.
,
Liu
D.
,
Hu
H.
,
Dong
Z.
,
Wang
T.
&
Ming
G.
2023
Projection of rainfed rice yield using CMIP6 in the Lower Lancang–Mekong River Basin
.
Agronomy
13
(
6
),
1504
.
Yadav
R. S.
&
Bhutan
C.
2001
Effect of moisture stress on growth and yield in rice genotypes
.
Indian Journal of Agricultural Research
2
,
104
107
.
Yazdani
A.
,
Saedi
M.
&
Babaei
A.
1990
Measurement of rice water consumption in the farms of Isfahan province. Research report of 1371. Soil and water research, Department of Isfahan Province Agricultural Research Center, Iran
.
Zou
M.
,
Zhou
S.
,
Zhou
Y.
,
Jia
Z.
,
Guo
T.
&
Wang
J.
2021
Cadmium pollution of soil-rice ecosystems in rice cultivation dominated regions in China: A review
.
Environmental Pollution
280
,
116965
.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY-NC-ND 4.0), which permits copying and redistribution for non-commercial purposes with no derivatives, provided the original work is properly cited (http://creativecommons.org/licenses/by-nc-nd/4.0/).