Irrigation Water Allocation Research Articles

The iGains4Gains model guides irrigation water conservation and allocation to enhance nexus gains across water, food, carbon emissions, and nature

The iGains4Gains model guides irrigation water conservation and allocation to enhance nexus gains across water, food, carbon emissions, and nature

Irrigation Water Allocation for Enhanced Productivity and Economic Gain of Haricot Bean (Phaseolus vulgaris): A Study in Semi-arid Region of Ethiopia

This study aimed to evaluate the impact of varying irrigation levels on haricot bean yield and its related attributes. The experiment was conducted with five irrigation treatments: 60%, 80%, 100%, 120%, and 140% Manageable Allowed Depletion (MAD). The results revealed that the 80% MAD treatment produced the highest haricot bean yields, with 25.03, 26.07, and 23.46 qt/ha in 2016, 2017, and 2018, respectively, with no significant difference from the 100% MAD treatment. The lowest yields per hectare were observed under the 140% MAD treatment, with yields of 18.05, 18.6, and 15.45 qt/ha respectively, across the same years. The average maximum yield across all 3 years was 24.84 qt/ha for the 80% MAD treatment, whereas the minimum was 17.36 qt/ha for the 140% MAD treatment. Water productivity was lowest at 4.32 kg/mm for the 60% and 140% MAD treatments, while the highest values were recorded at 6.09 and 6.07 kg/mm for the 100% and 80% MAD treatments, respectively. Economically, the 80% MAD treatment yielded the highest economic gain of 30,193.1 birr/ha. Therefore, based on these findings, applying 80% MAD under furrow irrigation is recommended for optimal haricot bean production in the semi-arid regions of Ethiopia and similar environments.

Evaluation of coupled SWAT-MODFLOW-NWT model for conjunctive use of surface water and groundwater resources in the Mahabad plain of Iran

The Urmia Lake Basin has been severely affected by the unbalanced exploitation of water resources. To better manage the use of integrated water resources, the coupled SWAT-MODFLOW-NWT was adopted for the Mahabad Plain in the Urmia Lake Basin, N.W. Iran. The results indicated that a multifunctional calibration of SWAT and MODFLOW-NWT hydrological models in a large-scale irrigated area was necessary, using parameters such as evapotranspiration and crop yield in addition to the usual surface runoff and water table measures. The coupled model was then used to evaluate several water allocation scenarios, such as alternate proportions of irrigation water allocation from conjunctive water resources. The ultimate objective of adopting these scenarios was to increase the residual share of the water supply in order to compensate for the deprived share of Urmia Lake. The results of this study demonstrated that that the coupled SWAT-MODFLOW-NWT model was able to satisfactorily simulate the surface and groundwater balance components at different spatial and temporal dimensions. The results indicate that the Mahabad aquifer is capable of supplying irrigation water needs in the central and northern regions, with some limitations around running rivers. Furthermore, groundwater sustainability indicators showed that even with an additional 30% of the water supply from groundwater, the long-term sustainability of groundwater resources was preserved Ultimately, the findings indicated that a reduction in water allocation from surface waters can lead to an increase in water release to the lake of 16 million cubic meters (21%) to 18 million cubic meters (25%) in different years. The outcomes of this study can serve as a guiding principle for the optimal and sustainable allocation of surface and groundwater resources in highly competitive and fragile basins such as Lake Urmia.

Soil moisture retrieval from dual-polarized Sentinel-1 SAR data over agricultural regions using a water cloud model.

The accurate retrieval of soil moisture plays a pivotal role in agriculture, particularly in effective irrigation water management, as it significantly affects crop growth and yield. The present study mainly focuses on the robustly investigated capability of dual-polarized Sentinel-1 SAR-derived vegetation descriptors in the water cloud model (WCM) in surface soil moisture (SSM) retrieval over wheat crops. The vegetation descriptors used in the study are radar vegetation index (RVI), backscattering ratio, polarimetric radar vegetation index (PRVI), dual polarization SAR vegetation index (DPSVI), and dual polarimetric radar vegetation index (DpRVI). The results of the WCM model illustrate that all the models show acceptable results, which confirms that this vegetative descriptor can be useful to estimate the accurate soil moisture over the wheat crop in the study area, except for DPSVI. Furthermore, the results revealed that model performances gradually decrease as the crop enters the complex stages. In summary, the overall finding demonstrates that PRVI outperformed other models in terms of statistical indicators value for calibration (R2 = 0.728, NSE = 0.727, PBIAS = - 2.67%, and RMSE = 2.985%) and validation (R2 = 0.728, NSE = 0.684, PBIAS = - 13.666%, and RMSE = 4.106%). Thus, overall results proved that the WCM model has considerable potential to retrieve SSM over wheat crops from Sentinel-1 satellite data. This study will be beneficial for regional water resources managers for proper allocation of irrigation water, effective irrigation management, and enhancedirrigation efficiency within the regions.

A Multi-Objective Simulation-Optimization framework for water resources management in canal-well conjunctive irrigation area based on nexus perspective

A Multi-Objective Simulation-Optimization framework for water resources management in canal-well conjunctive irrigation area based on nexus perspective

Uncertain multi‐objective programming approach for planning supplementary irrigation areas in rainfed agricultural regions

AbstractRainfed agriculture is crucial for ensuring global food and water security, and supplementary irrigation is an effective means of improving the economic benefits in rainfed agricultural regions. This study proposes a novel uncertain optimization approach to optimize supplementary irrigation areas in rainfed agricultural regions. The approach incorporates multi‐objective linear programming, interval linear programming, fuzzy goal programming and stochastic expected value programming. In the proposed interval multi‐fuzzy goal stochastic expected‐value programming, uncertainties are expressed in the form of discrete intervals, probability distributions and fuzzy goals. This approach, which considers the randomness of precipitation during the optimization process and allocates limited irrigation water resources to different subareas and crops, was applied to a case study of crop irrigation area planning in Guyuan City, Ningxia Hui Autonomous Region, northwestern China. The maximum economic benefits and the minimum sum of the Gini coefficients among the different subareas and crops were regarded as the planning objectives, and a series of optimal irrigation areas with different crops and subareas under different water levels were obtained. The optimization results revealed that vegetables and fruits consumed large amounts of irrigation water to increase their economic benefits. In addition, allocating a large amount of irrigation water to wheat is essential to decrease the Gini coefficient and meet food security constraints, particularly at extremely low water levels. Compared with current management, the optimized irrigation area decreased by 30%, the crop water deficit index increased by 9%, the economic benefits increased by 3% and the total Gini coefficient of crops decreased by 17%, indicating that the optimization approach could fairly and reasonably allocate irrigation water resources. Our research provides a mathematical approach for decision‐makers to plan supplementary irrigation areas in rainfed agricultural regions.

Effect of Gender and Generation on the Adoption of Irrigation and Good Farming Practices in Bontanga and Golinga Irrigation Schemes in Northern Ghana

This study examined the challenges faced by men, women, and different age groups in irrigation water management and farming practices in the Bontanga and Golinga irrigation schemes. The results of the study revealed that there are significant differences in irrigation and farming practices between men and women as well as between older and younger farmers. For men, the main challenges were; limited access to financial resources for investing in modern irrigation technologies and equipment, inadequate knowledge and awareness of sustainable farming practices and water management insufficient government support, and lack of policies tailored to their specific needs. For women, these were gender inequalities and limited access to land, water, and productive resources, lack of control and decision-making power over irrigation water allocation, and limited access to training and extension services to enhance their farming skills. Youth recognized limited interest and involvement in agriculture due to the perception of low profitability and lack of modernization, inadequate access to education and training opportunities in agricultural practices and water management, and insufficient support and mentorship programs to encourage youth participation in farming.

Assessing crop yield and water balance in crop rotation irrigation systems: Exploring sensitivity to soil hydraulic characteristics and initial moisture conditions in the North China Plain

Assessing crop yield and water balance in crop rotation irrigation systems: Exploring sensitivity to soil hydraulic characteristics and initial moisture conditions in the North China Plain

Water, Salt, and Ion Transport and Its Response to Water-Saving Irrigation in the Hetao Irrigation District Based on the SWAT-Salt Model

Soil salinization is one of the main hazards affecting the sustainable development of agriculture in the Hetao Irrigation District (HID) of Inner Mongolia. To grasp the water and salt transport patterns and spatial–temporal distribution characteristics of the HID at the regional scale, the improved Soil and Water Assessment Tool with a salinity module (SWAT-Salt) model was used to establish the distributed water and salt transport model for the watershed in this study. The results demonstrated that the modified model could more accurately represent the process of water and salt changes in the HID. The coefficient of determination (R2) in the simulation of streamflow and discharge salt loading was 0.83 and 0.86, respectively, and the Nash–Sutcliffe efficiency (NSE) was 0.80 and 0.74, respectively. Based on this, different hydrological processes (surface runoff, lateral flow, groundwater, soil seepage) as well as spatial–temporal distribution characteristics of water salinity in groundwater and soil were analyzed in the HID. Differences in groundwater and soil salinity in different land uses and soil types were also compared. Of these, surface runoff and lateral flow salt discharge loading are concentrated in the southwestern portion of the basin, while groundwater salt discharge loading is concentrated in the eastern as well as southwestern portions of the basin. The salt discharge loading from groundwater accounts for about 98.7% of the total salt discharge loading from all hydrological pathways and is the major contributing part of salt discharge from the irrigation area. Soil salinity increases gradually from west to east. Groundwater salinity (2946 mg/L) and soil water electrical conductivity (0.309 dS/m) were minimized in the cropland. Meanwhile, rational allocation of irrigation water can appropriately increase the amount of salt discharge loading. In conclusion, the model could provide a reference for the investigation of soil salinization and water–salt management measures in irrigation areas.

Socioeconomic impact of agricultural water reallocation policies in the Upper Litani Basin (Lebanon): a remote sensing and microeconomic ensemble forecasting approach

Socioeconomic impact of agricultural water reallocation policies in the Upper Litani Basin (Lebanon): a remote sensing and microeconomic ensemble forecasting approach

Advanced evapotranspiration forecasting in Central Italy: Stacked MLP-RF algorithm and correlated Nystrom views with feature selection strategies

Advanced evapotranspiration forecasting in Central Italy: Stacked MLP-RF algorithm and correlated Nystrom views with feature selection strategies

Optimizing crop planning in the winter fallow season using residual soil nutrients and irrigation water allocation in India

Effective management of water resources is essential for crop diversification and food security. This study proposes an Irrigation-Food-Environment-Chance-constrained Programming (IFEC) model for simultaneously optimizing crop planting area, irrigation water, and residual fertilizer considering inflow uncertainty along with farmer preference crop. Eight irrigation water allocation optimal models were constructed, fixing the preference crop cultivation area, while deviations in downstream release, and vegetable crop area cultivation were executed for sensitivity analysis. Model is then applied in a command area fed by a sub-tributary of Brahmaputra, India. On averaging, plant available N and P for the area were 62.14kgha-1 and 1.13kgha-1 respectively. With variation in available water, changes would occur in vegetable and cereal crops having higher yield and relatively less crop water requirement as compared to maize. Results showed that complying with preference crop area up to 60% would decrease the profit by 49% as compared to 20% at even 10% risk probability for 70% release. At existing conditions, water would be insufficient at 60% preference crop. Further, R2 value between benefit and water availability for vegetable cultivation varies from 0.99 to 0.78 for all scenarios. The tool featured that, setting specific preference crop areas provides equitable situation rather than mono-cropping. From the study findings, we suggest two salient recommendations: (1) promoting policies with appropriate financial subsidies for vegetable cultivation that focus on intensification with less water-requiring crops and (2) optimization results could be achieved by expanding the water utilization in the present condition while increasing efficiency.

ROLES OF TRADITIONAL IRRIGATION SYSTEM IN SUPPORTING RICE FARMING DEVELOPMENT: Lessons Learned from Bali Province, Indonesia

Agricultural development has still had significant roles on economic development in Indonesia. Rice farming is addressed to increase the productivity and quality of product by using improved agricultural practices including irrigation water management. In Bali province (Indonesia), the existence of subak as traditional irrigation system with socio-agrarian-religious in nature, could be a one of the local cultural institutions for supporting government in the food security program. The main functions of subak are distributing and allocating irrigation water among the subak’s members and between or among the subaks which are getting water from the separated dams on a similar river. These functions are supported by the implementation of internal by-laws own by each subak governing the mechanism of planting schedule, cropping patterns, water borrowing, including ritual ceremonies conducted in the relation to phases of rice planting. Subak system as social capital, therefore, could ensure the availability of irrigation water over the year. Thus, the rice farming development programmed by government could be achived by the effective subak system.

A wise irrigation to contribute to integrated water resource management

Irrigated agriculture accounts for about 20% of cultivated lands worldwide while currently generating an estimated 40% of crop production, and two-thirds of future gains in crop production are expected to come from irrigated lands. Therefore, irrigation is strategic to ensure food for the world’s increasing population and slow down the pace of deforestation. Irrigated agriculture also accounts for more than 70% of global water withdrawals, and the way agriculture uses freshwater is crucial for ensuring availability for other activities and preserving water-related ecosystems. To give an agri-environmental interpretation of the water fluxes involved in irrigation, the total amount of water withdrawn from a source is called white water (W) and subdivided as follows: gold water (G) is the amount that is actually used by the crops. This fraction represents the ultimate goal of irrigation, which is to increase crop productivity and food availability. We can also consider this amount as the irrigation water for crops. The gold color means an income for the farm; emerald water (E) is the amount of water withdrawn for irrigation that does not reach the crops but provides ecosystem services, i.e., the benefits that people get from ecosystems. This amount of water is useful for the community and can be identified as irrigation of the territory; red water (R) is losses, i.e., the fraction of water that has to be reduced as much as possible if not eliminated. It is an economic, social and environmental cost; the red color is associated with the red traffic light that means STOP! The quantification of W has to be preceded by a careful evaluation of the benefits achievable with irrigation in relation to the environmental characteristics of the cultivation area. Strategic issues at this stage are the choice between full or deficit irrigation and the individuation of opportunities to exploration of opportunities to increase the availability of water resources by using non-conventional sources. The quantification of G and E fluxes is necessary to reduce losses, while strategies/techniques useful to reduce irrigation needs at the field level are key factors to allocate irrigation water within the framework of an integrated and sustainable management of water aimed at turning user conflicts into synergies. This implies multiple subjects and actors in a multi-disciplinary approach.

Modeling GA-derived optimization analysis for canal-based irrigation water allocation under variations in runoff-related and irrigation-related factors

Modeling GA-derived optimization analysis for canal-based irrigation water allocation under variations in runoff-related and irrigation-related factors

Newspaper coverage of water security issues in the water‐stressed Northern Province of Sri Lanka: An explorative study of three Tamil dailies

AbstractNewspapers remain as an effective medium for circulating information among the public in the North of Sri Lanka and have the potential to influence public opinion and people's behavior regarding sustainable use of groundwater. This study investigated the extent and scope of newspaper coverage on the subject of water security in the Northern Province of Sri Lanka. Three newspapers, namely, Yarl Thinakkural, Uthayan, and Valampuri were chosen on the basis of readership, circulation in print form, and for being daily local or regional papers in Tamil. The content analysis of 1214 articles published in 2019 and 2020 in the three papers indicated that as much as 80% of space in the papers was allocated to reporting general news items and events in the community related to new water projects, rain and floods or drought events and announcements of allocation of irrigation water for farming. Only 20% of newspaper space was taken up by non‐news articles including advertisements related to water. We conclude by saying that the effect of these newspapers on their audiences would merely be to inform rather than to set agendas or frame the discourse in society, let alone persuade readers enough to make changes. The study revealed the significant potential that exists for newspapers to shift their culture of simply reporting of facts in a dispassionate way to one of environmental journalism with a degree of advocacy in view of the critical nature of the security of groundwater in the Northern Province.

Adaptability of Maize Farmers to Drought and the Selection of Irrigation Period—A Survey of Irrigation Behavior of Farmers in the Three Provinces of Huang-Huai-Hai, China

The summer maize area of Huang-Huai-Hai is the main summer maize production area in China, droughts occur frequently during the growth period of summer maize and irrigation water resources are scarce in this region. This paper studied the adaptability of maize farmers to drought and the selection of irrigation period in the three provinces of Huang-Huai-Hai. The adaptability index of irrigation at different growth stages was analyzed by establishing an extended C-D production function model, while the marginal income of irrigation in each growth period was calculated based on the estimation results of adaptability index model. The results showed that: (1) The growth period with the largest adaptability index in the three provinces of Huang-Huai-Hai was milk ripening stage. The adaptability index in milk ripening stage in Hebei, Henan, and Shandong was 1.063, 1.081, and 1.053, respectively. (2) The maize key growth periods of water sensitivity in the three provinces of Huang-Huai-Hai were tasseling period and milk ripening period, and in most cases, the irrigation period of farmers was consistent with the key growth period of water sensitivity. (3) In Hebei, Henan, and Shandong provinces, the marginal benefits of irrigation were greater than the marginal costs in each growth period. The marginal income of irrigation during tasseling period in the three provinces was relatively large, and tasseling period was the preferred irrigation period of most farmers. To optimize future irrigation water allocation, farmers should prioritize ensuring sufficient water supply during tasseling stage and milk ripening stage in Hebei and Shandong, and during big bell mouth stage and tasseling stage in Henan.

A simulation-based multi-objective two-level optimization decision-making approach for supporting balanced irrigation water management

In this study, a simulation-based multi-objective two-level optimization decision-making approach is developed for optimal irrigation water allocation, improving irrigation water productivity and controlling regional accumulated salts. Techniques of multi-objective programming, two-level programming and simulation model of water and salt physical movement process are incorporated into the modeling framework. The simulated processes are parameterized and calibrated with field experimental data while the optimization model is used to generate optimal solutions though predefined objectives and the associated constraints. This model is applied to a case study on irrigation water allocation in the Jiefangzha Irrigation Subarea in Hetao Irrigation District, Northwest China. Firstly, the study area is delineated into several homogeneous irrigation decision-making units (IDMUs) for better characterizing their spatial variability because it’s spatially heterogeneous. Afterwards, decomposition-coordination algorithm is introduced to solve such an integrated simulation-based multi-objective two-level optimization model. Finally, optimal solutions of irrigation water allocation for different crops during crop growth periods in different IDMUs can be obtained for supporting sustainable strategies of irrigation. The results can achieve balanced tradeoffs between different stakeholders (i.e., the upper-level decision-makers and the lower-level farmers) and between conflicting economic objectives and environmental objectives. Moreover, optimal solutions have a slight increase in economic returns over the baseline scenario (i.e., status quo), but the irrigation water productivity is increased by nearly 60% due to less irrigation water used. Regional accumulated salts can be controlled because the soil salinity is constrained within the predetermined salt accumulation constraint. Therefore, these findings can provide evidence for efficient use of irrigation water resources and further support of sustainable irrigated agriculture.

Assessment of irrigation water allocation, Koftu, Ethiopia

Abstract This research investigates the fair and efficient distribution of water among irrigators, focusing on the timely and uniform delivery of water. To achieve this, the study utilized various methods such as group discussions, critical informant and expert interviews, and field flow measurements. The degree of fairness in the distribution of irrigation water was determined by analyzing the shift in the relative water supply to end users. The effectiveness of irrigation is inversely proportional to the relative irrigation supply, which can be observed in the scheme's water delivery indicators. The study found that while the estimated delivered flow of water in the head, middle, and tail reaches of the canal was 1.21, 0.58, and 0.23 m3/s respectively, the required quantity of discharge was only 0.81, 0.31, and 0.15 m3/s. This discrepancy resulted in the inadequate, unreliable, and unequal water supply to irrigators. The research revealed that canal operation and maintenance were the main factors limiting the system's capacity. The findings showed that the adequacy, dependability, equality, and efficiency values were 0.8, 0.14, 0.40, and 0.71, respectively, suggesting that improvements are needed to ensure the timely and equitable distribution of water to irrigators.

Rice irrigation water efficiency improvement: An AquaCrop-based optimization modeling approach

Rice is the cereal crop that consumes the largest amount of water in the world. To improve the water use efficiency of rice farming and promote the sustainable development of rice production, this study proposes a novel AquaCrop-based optimization modeling approach. First, an AquaCrop-based multiobjective model is constructed to generate dynamic water production functions (WPFs). The NSGA-II algorithm is employed to solve the model, and quadratic dynamic WPFs for rice under different hydrological years (wet, normal and dry) are generated based on the obtained Pareto fronts, which can improve the modeling efficiency and help reflect the complicated reality of water flows. Second, a fuzzy credibility-constrained stochastic multiobjective programming (FCC-SMOP) model is developed for irrigation water allocation based on the acquired WPFs. The model addresses the randomness of precipitation and runoff, the fuzziness of decision-makers' preferences, and conflicting objectives of water savings, benefit increments, and water demand during the critical period of rice growth. The proposed simulation-optimization approach was applied to the Changgang irrigation district in northeast China. Optimal irrigation amounts under different decision-making preference scenarios (including conservative, moderate and positive) and different hydrological years were simultaneously generated. The following conclusions can be drawn: (1) The AquaCrop-based multiobjective method is capable of generating WPFs of different hydrological years with sparse discontinuous field experiments; (2) the decision-making preferences of decision-makers significantly impact the economic benefits, water use efficiency, and practicality of schemes; and (3) the FCC-SMOP model successfully makes tradeoffs among the three objectives under multiple uncertainties and can further improve the system efficiency and increase planting income in the Changgang irrigation district when its irrigation facilities become optimal.