Untangling the effects of shallow groundwater and deficit irrigation on irrigation water productivity in arid region: New conceptual model

Abstract. The temporal and spatial distributions of regional irrigation water productivity (RIWP) are crucial for making decisions related to agriculture, especially in arid irrigated areas with complex cropping patterns. Thus, in this study, we developed a new RIWP model for an irrigated agricultural area with complex cropping patterns. The model couples the irrigation- and drainage-driven soil water and salinity dynamics and shallow groundwater movement in order to quantify the temporal and spatial distributions of the target hydrological and biophysical variables. We divided the study area into 1 km × 1 km hydrological response units (HRUs). In each HRU, we considered four land use types: sunflower fields, wheat fields, maize fields, and uncultivated lands (bare soil). We coupled the regional soil hydrological processes and groundwater flow by taking a weighted average of the water exchange between unsaturated soil and groundwater under different land use types. The RIWP model was calibrated and validated using 8 years of hydrological variables obtained from regional observation sites in a typical arid irrigation area in North China, the Hetao Irrigation District. The model simulated soil moisture and salinity reasonably well as well as groundwater table depths and salinity. However, overestimations of groundwater discharge were detected in both the calibration and validation due to the assumption of well-operated drainage ditch conditions; regional evapotranspiration (ET) was reasonably estimated, whereas ET in the uncultivated area was slightly underestimated in the RIWP model. A sensitivity analysis indicated that the soil evaporation coefficient and the specific yield were the key parameters for the RIWP simulation. The results showed that the RIWP decreased from maize to sunflower to wheat from 2006 to 2013. It was also found that the maximum RIWP was reached when the groundwater table depth was between 2 and 4 m, regardless of the irrigation water depth applied. This implies the importance of groundwater table control on the RIWP. Overall, our distributed RIWP model can effectively simulate the temporal and spatial distribution of the RIWP and provide critical water allocation suggestions for decision-makers.

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A novel regional irrigation water productivity model for complex cropping patterns in arid regions coupling soil water and salinity dynamics, irrigation and drainage, and shallow groundwater movement

10.5194/hess-2019-359 ◽

2019 ◽

Author(s):

Jingyuan Xue ◽

Zailin Huo ◽

Ian White ◽

Isaya Kisekka ◽

Zhuping Sheng ◽

...

Keyword(s):

Irrigation Water ◽

Water Productivity ◽

Shallow Groundwater ◽

Groundwater Table ◽

Temporal And Spatial Distribution ◽

Cropping Patterns ◽

Groundwater Movement ◽

Land Use Types ◽

Temporal And Spatial ◽

Irrigation Water Productivity

Abstract. The temporal and spatial distribution of regional irrigation water productivity (RIWP) is crucial for making agricultural related decisions, especially in arid irrigated areas with complex cropping patterns. Thus, we developed a new RIWP model for an irrigated agricultural area with complex cropping patterns. The model couples the irrigation and drainage driven soil water and salinity dynamics and shallow groundwater movement, to quantify the temporal and spatial distributions of the target hydrological and biophysical variables. We divided the study area into 1 km×1 km hydrological response units (HRUs). In each HRU, we considered four land-use types: sunflower fields, wheat fields, maize fields and uncultivated lands. And we coupled the regional soil hydrological processes and groundwater flow by taking a weighted average of the water exchange between unsaturated soil and groundwater under different land-use types. The RIWP model was calibrated and validated using eight years of hydrological variables obtained from regional observation sites in a typical arid irrigation area of North China, Hetao Irrigation District. The model reasonably well simulated soil moisture and salinity, groundwater table depths, salinity, and discharge, and regional evapotranspiration. Sensitivity analysis indicates that soil evaporation coefficient and specific yield are the key parameters for RIWP simulation. The results showed that, from 2006 to 2013, RIWP decreased from maize to sunflower to wheat. It was found that the maximum RIWP can be reached when groundwater table depth is in the range of 2 m to 4 m, regardless of irrigation water depths. This implies the importance of groundwater table control on RIWP. Overall, our distributed RIWP model can effectively simulate the temporal and spatial distribution of RIWP and provide critical water allocation suggestions for decision makers.

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Crop yield and irrigation water productivity of silage maize under two water stress strategies in semi-arid environment: Two different pot and field experiments

Agricultural Water Management ◽

10.1016/j.agwat.2021.106999 ◽

2021 ◽

Vol 255 ◽

pp. 106999

Author(s):

Mahdi Gheysari ◽

Fatemeh Pirnajmedin ◽

Hamid Movahedrad ◽

Mohammad Mahdi Majidi ◽

Mohammad Javad Zareian

Keyword(s):

Water Stress ◽

Crop Yield ◽

Irrigation Water ◽

Field Experiments ◽

Water Productivity ◽

Arid Environment ◽

Silage Maize ◽

Semi Arid ◽

Irrigation Water Productivity

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High Nitrogen Fertilization Modulates Morpho-Physiological Responses, Yield, and Water Productivity of Lowland Rice under Deficit Irrigation

Agronomy ◽

10.3390/agronomy11071291 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1291

Author(s):

Nasr M. Abdou ◽

Mohamed A. Abdel-Razek ◽

Shimaa A. Abd El-Mageed ◽

Wael M. Semida ◽

Ahmed A. A. Leilah ◽

...

Keyword(s):

Nitrogen Fertilizer ◽

Irrigation Water ◽

Nitrogen Fertilization ◽

Deficit Irrigation ◽

Physiological Responses ◽

Water Productivity ◽

Water Shortage ◽

Rice Production ◽

Lowland Rice ◽

Nitrogen Fertilizers

Sustainability of rice production under flooding conditions has been challenged by water shortage and food demand. Applying higher nitrogen fertilization could be a practical solution to alleviate the deleterious effects of water stress on lowland rice (Oryza sativa L.) in semi-arid conditions. For this purpose, field experiments were conducted during the summer of 2017 and 2018 seasons. These trials were conducted as split-split based on randomized complete blocks design with soil moisture regimes at three levels (120, 100 and 80% of crop evapotranspiration (ETc), nitrogen fertilizers at two levels (N1—165 and N2—200 kg N ha−1) and three lowland Egyptian rice varieties [V1 (Giza178), V2 (Giza177) and V3 (Sakha104)] using three replications. For all varieties, growth (plant height, tillers No, effective tillers no), water status ((relative water content RWC, and membrane stability index, MSI), physiological responses (chlorophyll fluorescence, Relative chlorophyll content (SPAD), and yield were significantly increased with higher addition of nitrogen fertilizer under all water regimes. Variety V1 produced the highest grain yield compared to other varieties and the increases were 38% and 15% compared with V2 and V3, respectively. Increasing nitrogen up to 200 kg N ha−1 (N2) resulted in an increase in grain and straw yields by 12.7 and 18.2%, respectively, compared with N1. The highest irrigation water productivity (IWP) was recorded under I2 (0.89 kg m−3) compared to (0.83 kg m−3) and (0.82 kg m−3) for I1 and I3, respectively. Therefore, the new applied agro-management practice (deficit irrigation and higher nitrogen fertilizer) effectively saved irrigation water input by 50–60% when compared with the traditional cultivation method (flooding system). Hence, the new proposed innovative method for rice cultivation could be a promising strategy for enhancing the sustainability of rice production under water shortage conditions.

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Can Sustained Deficit Irrigation Save Water and Meet the Quality Characteristics of Mango?

Agriculture ◽

10.3390/agriculture11050448 ◽

2021 ◽

Vol 11 (5) ◽

pp. 448

Author(s):

Leontina Lipan ◽

Aarón A. Carbonell-Pedro ◽

Belén Cárceles Rodríguez ◽

Víctor Hugo Durán-Zuazo ◽

Dionisio Franco Tarifa ◽

...

Keyword(s):

Irrigation Water ◽

Deficit Irrigation ◽

Block Design ◽

Water Productivity ◽

Titratable Acidity ◽

Soluble Solids ◽

Total Phenolic ◽

Drought Tolerant ◽

Randomized Block Design ◽

Peel Color

Mango is one of the most cultivated tropical fruits worldwide and one of few drought-tolerant plants. Thus, in this study the effect of a sustained deficit irrigation (SDI) strategy on mango yield and quality was assessed with the aim of reducing irrigation water in mango crop. A randomized block design with four treatments was developed: (i) full irrigation (FI), assuring the crop’s water needs, and three levels of SDI receiving 75%, 50%, and 33% of irrigation water (SDI75, SDI50, and SDI33). Yield, morphology, color, titratable acidity (TA), total soluble solids (TSS), organic acids (OA), sugars, minerals, fiber, antioxidant activity (AA), and total phenolic content (TPC) were analyzed. The yield was reduced in SDI conditions (8%, 11%, and 20% for SDI75, SDI50, and SDI33, respectively), but the irrigation water productivity was higher in all SDI regimes. SDI significantly reduced the mango size, with SDI33 generating the smallest mangoes. Peel color significantly changed after 13 days of ripening, with SDI75 being the least ripe. The TA, AA, and citric acid were higher in SDI75, while the TPC and fiber increased in all SDI levels. Consequently, SDI reduced the mango size but increased the functionality of samples, without a severe detrimental effect on the yield.

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Development and Evaluation of a Variable-Rate Irrigation Management Method in the Mississippi Delta

Transactions of the ASABE ◽

10.13031/trans.14019 ◽

2021 ◽

Vol 64 (1) ◽

pp. 287-298

Author(s):

Ruixiu Sui ◽

Jonnie Baggard

Keyword(s):

Electrical Conductivity ◽

Soil Moisture ◽

Water Use ◽

Irrigation Water ◽

Mississippi Delta ◽

Water Productivity ◽

Variable Rate ◽

Irrigation Water Use ◽

Irrigation Water Productivity ◽

Variable Rate Irrigation

HighlightsWe developed and evaluated a variable-rate irrigation (VRI) management method for five crop years in the Mississippi Delta.VRI management significantly reduced irrigation water use in comparison with uniform-rate irrigation (URI). There was no significant difference in grain yield and irrigation water productivity between VRI and URI management.Soil apparent electrical conductivity (ECa) was used to delineate irrigation management zones and generate VRI prescriptions.Sensor-measured soil water content was used in irrigation scheduling.Abstract. Variable-rate irrigation (VRI) allows producers to site-specifically apply irrigation water at variable rates within a field to account for the temporal and spatial variability in soil and plant characteristics. Developing practical VRI methods and documenting the benefits of VRI application are critical to accelerate the adoption of VRI technologies. Using apparent soil electrical conductivity (ECa) and soil moisture sensors, a VRI method was developed and evaluated with corn and soybean for five crop years in the Mississippi Delta. Soil ECa of the study fields was mapped and used to delineate VRI management zones and create VRI prescriptions. Irrigation was scheduled using soil volumetric water content measured by soil moisture sensors. A center pivot VRI system was employed to deliver irrigation water according to the VRI prescription. Grain yield, irrigation water use, and irrigation water productivity in the VRI treatment were determined and compared with that in a uniform-rate irrigation (URI) treatment. Results showed that the grain yield and irrigation water productivity between the VRI and URI treatments were not statistically different with both corn and soybean crops. The VRI management significantly reduced the amount of irrigation water by 22% in corn and by 11% in soybean (p = 0.05). Adoption of VRI management could improve irrigation water use efficiency in the Mississippi Delta. Keywords: Soil electrical conductivity, Soil moisture sensor, Variable rate irrigation, Water management.

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