This study aims to investigate the influence of treated wastewater (TWW) on the hydraulic performance of drip irrigation emitters. A field experiment was conducted in order to test two types of online emitters, a low pressure (LP) and a standard pressure (SP), at different working pressures (0.25 bar, 0.50 bar, and 1.00 bar) using TWW. The emitters were initially evaluated in the laboratory and the field for the discharge exponent (X), discharge coefficient (Kd), average emitter discharge (Q_avg), coefficient of variation (CV), distribution uniformity (DU), the mean discharge ratio (Dra), and the main degree of clogging (DC). The main effect of the emitters on the hydraulic parameters of irrigation performance was not significant, while the operational pressure and operational time of irrigation had a significant effect. For the LP emitter, the average emitter discharge was 7.6, 7.7, and 7.8 Lh⁻¹ at 0.25, 0.50, and 1.00 bar, respectively. For the SP emitter, the average emitter discharge was 7.6, 7.8, and 7.8 Lh⁻¹ at 0.25, 0.50, and 1.00 bar, respectively. The EU values for the LP and SP emitters varied from low to moderate at 0.25 bar, as the EU values at 0.50 and 1.00 bar were considered high for both emitter types. Full article

The factors influencing the effective utilization coefficient of irrigation water are not understood well. It is usually considered that this coefficient is lower in areas with large-scale irrigation. With this background, we analyzed the effective utilization coefficient of irrigation water using the analytic hierarchy process using data from 2014 to 2019 in Shihezi City, Xinjiang. The weights of the influencing factors on the effective utilization coefficient of irrigation water in different irrigation areas were analyzed. Predictions of the coefficient’s values for different years were made by understanding the trends based on the grey model. The results show that the scale of the irrigation area is not the only factor determining the effective utilization coefficient of irrigation water. Irrigation technology, organizational integrity, crop types, water price management, local economic level, and channel seepage prevention are the most critical factors affecting the effective use of irrigation water. The grey model prediction results show that the effective utilization coefficient of farmland irrigation water will continuously increase and reach 0.7204 in 2029. This research can serve as a reference for government authorities to make scientific decisions on water-saving projects in irrigation districts in terms of management, operation, and investment. Full article

Sustainable agriculture in arid regions necessitates that the quality of groundwater be carefully monitored; otherwise, low-quality irrigation water may cause soil degradation and negatively impact crop productivity. This study aimed to evaluate the quality of groundwater samples collected from the wells in the quaternary aquifer, which are located in the Western Desert (WD) and the Central Nile Delta (CND), by integrating a multivariate analysis, proximal remote sensing data, and data-driven modeling (adaptive neuro-fuzzy inference system (ANFIS) and support vector machine regression (SVMR)). Data on the physiochemical parameters were subjected to multivariate analysis to ease the interpretation of groundwater quality. Then, six irrigation water quality indices (IWQIs) were calculated, and the original spectral reflectance (OSR) of groundwater samples were collected in the 302–1148 nm range, with the optimal spectral wavelength intervals corresponding to each of the six IWQIs determined through correlation coefficients (r). Finally, the performance of both the ANFIS and SVMR models for evaluating the IWQIs was investigated based on effective spectral reflectance bands. From the multivariate analysis, it was concluded that the combination of factor analysis and principal component analysis was found to be advantageous to examining and interpreting the behavior of groundwater quality in both regions, as well as predicting the variables that may impact groundwater quality by illuminating the relationship between physiochemical parameters and the factors or components of both analyses. The analysis of the six IWQIs revealed that the majority of groundwater samples from the CND were highly suitable for irrigation purposes, whereas most of the groundwater from the WD can be used with some limitations to avoid salinity and alkalinity issues in the long term. The high r values between the six IWQIs and OSR were located at wavelength intervals of 302–318, 358–900, and 1074–1148 nm, and the peak value of r for these was relatively flat. Finally, the ANFIS and SVMR both obtained satisfactory degrees of model accuracy for evaluating the IWQIs, but the ANFIS model (R² = 0.74–1.0) was superior to the SVMR (R² = 0.01–0.88) in both the training and testing series. Finally, the multivariate analysis was able to easily interpret groundwater quality and ground-based remote sensing on the basis of spectral reflectance bands via the ANFIS model, which could be used as a fast and low-cost onsite tool to estimate the IWQIs of groundwater. Full article

The COVID-19 pandemic is adversely impacting food and nutrition security and requires urgent attention from policymakers. Sustainable intensification of agriculture is one strategy that attempts to increase food production without adversely impacting the environment, by shifting from water-intensive crops to other climate-resistant and nutritious crops. This paper focuses on the Indian state of Andhra Pradesh by studying the impact of shifting 20% of the area under paddy and cotton cultivation to other crops like millets and pulses. Using FAO’s CROPWAT model, along with monsoon forecasts and detailed agricultural data, we simulate the crop water requirements across the study area. We simulate a business-as-usual base case and compare it to multiple crop diversification strategies using various parameters—food, calories, protein production, as well as groundwater and energy consumption. Results from this study indicate that reduced paddy cultivation decreases groundwater and energy consumption by around 9–10%, and a calorie deficit between 4 and 8%—making up this calorie deficit requires a 20–30% improvement in the yields of millets and pulses. We also propose policy interventions to incentivize the cultivation of nutritious and climate-resistant crops as a sustainable strategy towards strengthening food and nutrition security while lowering the environmental footprint of food production. Full article

Developing an appropriate irrigation schedule is essential in order to save water while at the same time maintaining high crop yields. The standard procedures of the field evaluation of distribution uniformity do not take into account the effects of the filling and emptying phases of the irrigation system. We hypothesized that, in sloping sandy soils, when short drip irrigation pulses are applied it is important to take into account the total water applied from the beginning of irrigation until the emptying of the irrigation system. To compute distribution uniformity, we sought to characterize the filling, stable pressure, and emptying phases of a standard strawberry irrigation system. We found that the shorter the time of the irrigation pulse, the worse the distribution uniformity and the potential application efficiency or zero deficit are. This effect occurs because as the volume of water applied during filling and emptying phases increases, the values of the irrigation performance indicators decrease. Including filling and emptying phases as causes of non-uniformity has practical implications for the management of drip irrigation systems in sloping sandy soils. Full article

Greenhouse horticultural crops are characterized by high levels of efficiency and productivity of irrigation water and nutrients applied. However, these indices may be affected by poor distribution uniformity of fertigation (DU). Different previous prospective studies show that there is a significant percentage of facilities with a low level of DU. However, there is no precise relationship between DU and the efficiency and productivity of water and fertilizers. This relationship may be affected by different factors, especially by the irrigation dose. The objective of this work was to determine the effect of the distribution uniformity of fertigation and the fertigation volume (FV) on the bio productive parameters and efficiency of water and nutrient use of the zucchini crop. The trial was developed in a greenhouse located in La Mojonera (Almería), on sanded soil. The greenhouse was equipped with an automated fertigation installation. The experimental design was randomized complete blocks with six treatments and three repetitions. The established treatment was a combination of two factors: distribution uniformity and fertigation volume. Three levels of DU were established: 100%, 75% and 50% approximately and two levels of fertigation volume: FV100% and FV70%. Volume of water and nutrients applied, soil matric potential (SMP), yield, biomass and efficiency in the water and nutrients use were determined. The maximum efficiency in the use of water and nutrients was obtained with a DU of 100% or 75% and a fertigation volume of FV70%, but this fertigation volume reduced the bio-productive parameters of the crop such as yield. The maximum yield and biomass were obtained with the volume of fertigation of 100% (FV100%), and with a DU of 100% or 75%. DU50% level reduced all bio-productive parameters, reducing yield by 45%, as well as the water use efficiency (WUE) and nutrient efficiency with any level of fertigation. Full article

Irrigation sustainability is particularly important in the vicinity of Doñana National Park (Huelva, Spain), where Europe’s most important wetland area coexists with a profitable strawberry irrigation activity. In this paper, an innovation and technology transfer project was laid out. The project was promoted by the Institute of Agricultural and Fisheries Research and Training (IFAPA), belonging to the Regional Government of Andalusia. The main objective of the project was to contribute to the sustainability of the complex ecological, productive, and social system of this region. The project was focused on the rational use of water resources. Experimentation, demonstration, technology transfer, and training activities were carried out, involving public administrations, companies, and private farms. The project was carried out in collaboration with strawberry companies covering a total surface area of 1900 hectares. Irrigation application efficiency and irrigation water productivity increased by 66% and there was also a significant increase in water saving (44%), without resulting production losses. The success of the activity was based on the implication of farmers in experimentation assignments. During a five-year time span, irrigation trials took place on several farms. This fact allowed a progressive improvement of irrigation management by farmers based on confidence in the experimental work results. Full article