Efficiency dynamics among onion growers in Maharashtra: a comparative analysis of drip irrigation adopters and non-adopters.

BACKGROUND: Onions are economically and nutritionally important vegetable crops. Despite advances in technology and acreage, Indian onion growers face challenges in realizing their full productivity potential. This study examines the technical efficiency of onion growers, the factors influencing it, and the constraints faced by those adopting drip irrigation in the Ghod river basin of western Maharashtra. A sample of 480 farmers including those practicing drip irrigation and those not practicing it, was selected from Junnar, Shirur, Parner, and Shrigonda blocks of the basin. The primary data was collected through semi-structured interviews. Analytical tools such as the Cobb-Douglas production function (represents technological relationship between multiple inputs and the resulting output), a single-stage stochastic frontier model, the Tobit model, and descriptive statistics were used to assess the technical efficiency of onion production at the farm level. RESULTS: According to the maximum likelihood estimates of the stochastic frontier analysis, drip adopters exhibited a mean technical efficiency of 92%, while for non-adopters it was 65%. It indicates that the use of drip irrigation technology is associated with higher technical efficiency. The association of technical efficiency and socio-economic characters of households showed that education, extension contacts, social participation, and use of information sources had a positive influence on technical efficiency, while family size had a negative influence on the drip irrigation adopters. For non-drip adopters, significant positive effects were observed for landholding, extension contact, and information source use. The major constraints faced by drip system adopters included a lack of knowledge about the proper operating techniques for drip systems and the cost of maintenance. CONCLUSION: The differences with inputs associated with two irrigation methods showed that the response of inputs to increase onion yield is greater for farmers who use drip irrigation than for farmers who do not, and are a result of the large differences in the technical efficiencies. These inefficiencies and other limitations following the introduction of drip irrigation, such as lack of knowledge about the proper operations, need to be addressed through tailored training for farmers and further interventions.

Investigating foliar application of bulk and nanoparticles titanium dioxide on fennel productivity to mitigate the negative effects of saline irrigation water.

BACKGROUND: Fennel essential oils are fragrance compounds used in food and pharmaceutical sectors. One of the major impediments to expansion of fennel farming in Egypt's reclamation areas is saline water. Titanium dioxide (TiO2) or TiO2 nano particles (TiO2NP) can be utilized to boost the yield of aromatic plants cultivated under saline irrigation water. Saline water, particularly which contains sodium chloride can harm fennel plant; consequently, it was predicted that fennel production would fail in Egypt's reclaimed area, where the primary source of irrigation is groundwater consisting sodium chloride. This study sought to help fennel respond to sodium chloride by applying Ti forms to their leaves in order to reduce the detrimental effects of sodium chloride on them for expanding their production in the newly reclamation areas as a natural source of essential oil. Ti forms were applied as foliar application at 0, 0.1, 0.2 TiO2, 0.1 TiO2NP, and 0.2 TiO2NP, mM under irrigation with fresh water (0.4 dS m-1), or saline water (51.3 mM or 4.7 dS m-1). RESULTS: Plants exposed to 0.1 mM TiO2NP under fresh water resulted in the maximum values of morphological characters, estragole, oxygenated monoterpenes and photosynthetic pigments; while those subjected to 0.1 mM TiO2NP under saline water gave the greatest values of essential oil, proline, antioxidant enzymes and phenols. The greatest amounts of soluble sugars were recorded with 0.2 mM TiO2NP irrigated with saline water. Plants subjected to 0 mM TiO2 under saline water produced the greatest values of flavonoids, hydrogen peroxide and malondialdehyde. CONCLUSION: To mitigate the negative effects of salty irrigation water on fennel plant production, TiO2NP application is suggested as a potential strategy.

Research progress in parameterizing irrigation and fertilization in land surface model.

Under the context of global climate change and growing population, irrigation and fertilization have become important ways to ensure food production, with consequences on water cycling, energy flow, and materials cycling in terrestrial ecosystems. In the land surface model (LSM), coupling irrigation and fertilization schemes are of great importance for clearly understanding the land-atmosphere interactions to ensure food security. We reviewed the expression methods of three key parameters, namely, the applied method, usage, and time in the parameterization process of irrigation and fertilization (nitrogen fertilizer) in LSM. We found that the ways to irrigate and ferti-lize in LSM are different from the ways used in actual practice due to the limitation of the high resolution of spatio-temporal data, which makes it difficult to understand the actual influences of irrigation and fertilization on grain yield, environment, and local climate. Finally, we proposed future works: 1) taking the differences of crop water demand into account and making the different irrigation thresholds for different crops to properly evaluate the total and intensity of water consumption of different crops; 2) using the field records and the regional grid data of fertilization and irrigation developed in recent years to develop parameterized schemes that are more in line with actual agricultural operations, which can accurately reveal their economic, ecological, and climatic effects; 3) developing fertilization diagnosis scheme considering crop type, phenological stage, and soil basic fertility as the supplementary scheme in LSM, to improve the applicability and simulation accuracy of LSM in the areas without nitrogen fertilizer data.

Assessment of antibiotic-resistant infection risks associated with reclaimed wastewater irrigation in intensive tomato cultivation.

Agricultural irrigation using reclaimed urban wastewater (RWW) represents a sustainable practice to meet the ever-increasing water stress in modern societies. However, the occurrence of residual antibiotics and antibiotic resistant bacteria (ARB) in RWW is an important human health concern. This study applied for the first time a novel Simple-Death dose-response model to the field data of Escherichia coli and Pseudomonas spp. collected from three greenhouses for cultivation of tomatoes irrigated with RWW. The model estimates the risk of infection by enteropathogenic E. coli associated with consumption of tomatoes and the risk of eye-infection caused by Pseudomonas aeruginosa in cultivation soil through hand-to-eye contacts. The fraction of antibiotic resistant (AR)-E. coli measured in irrigation water and AR-Pseudomonas spp. in soil was incorporated in the model to estimate the survival of ARB and antibiotic susceptible bacteria in the presence of trace level of antibiotics in human body. The results showed that the risk of E. coli infection through consumption of tomatoes irrigated with RWW is within the WHO and USEPA recommended risk threshold (<10-4); Pseudomonas aeruginosa eye-infection risk is at or below the acceptable risk level. The presence of residual antibiotic in human body reduced the overall risk probabilities of infections but selectively enhanced the survival of ARB in comparison to their susceptible counterparts, which resulted in antibiotic untreatable infection. Therefore, the outcomes of this study call for a new risk threshold for antibiotic untreatable infections and highlight the key importance of adopting work safety measures for better human health protection.

Developing climate change adaptation pathways in the agricultural sector based on robust decision-making approach (case study: Sefidroud Irrigation Network, Iran).

Allocation of water in the situation of climate change presents various uncertainties. Consequently, decisions must be made to ensure stability and functionality across different climatic scenarios. This study aims to examine the effectiveness of adaptation strategies in the agricultural sector, including a 5% increase in irrigation efficiency (S1) and a shift in irrigation method to Dry-DSR (direct seeded rice) under conditions of climatic uncertainty using a decision-making approach. The study focuses on the basin downstream of the Sefidroud dam, encompassing the Sefidroud irrigation and drainage network. Initially, basin modeling was conducted using the WEAP integrated management software for the period 2006-2020. Subsequently, the impact of climate change was assessed, considering RCP2.6, RCP4.5, and RCP8.5 emission scenarios on surface water resources from 2021 to 2050. Runoff and cultivated area, both subject to uncertainty, were identified as key parameters. To evaluate strategy performance under different uncertainties and determine the efficacy of each strategy, regret and satisfaction approaches were employed. Results indicate a projected decrease in future rainfall by 3.5-11.8% compared to the base period, accompanied by an increase in maximum and minimum temperatures (0.83-1.62 °C and 1.15-1.33 °C, respectively). Inflow to the Sefidroud dam is expected to decrease by 13-28%. Presently, the Sefidroud irrigation and drainage network faces an annual deficit of 505.4 MCM, and if current trends persist with the impact of climate change, this shortfall may increase to 932.7 MCM annually. Furthermore, satisfaction indices for strategy (S2) are 0.77 in an optimistic scenario and 0.70 in strategy (S1). In a pessimistic scenario, these indices are 0.67 and 0.56, respectively. Notably, changing the irrigation method with Dry-DSR is recommended as a robust strategy, demonstrating the ability to maintain basin stability under a broad range of uncertainties and climate change scenarios. It is crucial to note that the results solely highlight the effects of climate change on water sources entering the Sefidroud dam. Considering anthropogenic activities upstream of the Sefidroud basin, water resource shortages are expected to increase. Therefore, reallocating water resources and implementing practical and appropriate measures in this area are imperative.

Effects of irrigation scheduling on the yield and irrigation water productivity of cucumber in coconut coir culture.

Optimum irrigation scheduling is important for ensuring high yield and water productivity in substrate-cultivated vegetables and is determined based on information such as substrate water content, meteorological parameters, and crop growth. The aim of this study was to determine a precise irrigation schedule for coconut coir culture in a solar greenhouse by comparing the irrigation, evapotranspiration (ET), substrate water content (VWC), as well as the crop growth indices and yield of cucumber, and irrigation water productivity (IWP) under three irrigation schedules: the soil moisture sensor-based method (T-VWC), the accumulated radiation combined with soil moisture sensor-based method (Rn-VWC), and the crop evapotranspiration estimated method using the hourly PM-ETo equation with an improved calculation of Kc (T-ETc). The results showed that the daily irrigation and evapotranspiration amount were the highest under T-VWC treatment, while the lowest under T-ETc treatment. In different meteorological environments, the change in irrigation amount was more consistent with the ET,and the VWC was relatively stable in T-ETc treatment compared with that under T-VWC or Rn-VWC treatments. The plant height, leaves number, leaf area, and stem diameter of T-VWC and Rn-VWC treatments were higher than those of the T-ETc treatments, but there was no significant difference in cucumber yield. Compared with the T-VWC treatment, total irrigation amount under Rn-VWC and T-ETc treatments significantly decreased by 25.75% and 34.04%, respectively ([Formula: see text]). The highest IWP values of 25.07 kg m[Formula: see text] was achieved from T-ETc treatment with significantly increasing by 44.33% compared to the T-VWC treatment (17.37 kg m[Formula: see text]). In summary, the T-ETc treatment allowed more reasonable irrigation management and was appropriate for growing cucumber in coconut coir culture.

Long-term saline water irrigation has the potential to balance greenhouse gas emissions and cotton yield in North China plain.

Saline water has proven to be one of the alternative sources of freshwater for agricultural irrigation in water-scarce areas. However, the changes in farmland ecology caused by saline water irrigation remain unclear. In this study, six irrigation water salinities (CK: 1.3 dS m-1, S1: 3.4 dS m-1, S2: 7.1 dS m-1, S3: 10.6 dS m-1, S4: 14.1 dS m-1, S5: 17.7 dS m-1) were set in a three-year (2019, 2021-2022) experiment to investigate their effects on soil environment and greenhouse gas emissions in cotton fields under long-term saline water irrigation. Results show that soil salinity in the same layer increased as increasing water salinity. Soil moisture of S3-S5 increased significantly by 4.99-12.94%. There was no significant difference in soil organic matter content between CK and S1. Saline water irrigation increased soil ammonium nitrogen content by 0.57-49.26%, while decreasing nitrate nitrogen content by 1.43-32.03%. Soil CO2 and N2O emissions and CH4 uptake were lower in S1-S5 than in CK at different cotton growth stages. In addition, saline water irrigation reduced the global warming potential by 6.93-53.86%. A structural equation model was developed to show that soil salinity, moisture, and ammonium nitrogen content were negatively correlated with global warming potential, while organic matter and nitrate nitrogen had positive effects on global warming potential. Considering the comprehensive perspectives of gas emissions and cotton yield, irrigation water with salinity less than 10.6 dS m-1 could effectively reduce greenhouse gas emissions from cotton fields while maintaining stable cotton yields in the experimental area and similar region.

Impacts of irrigation with treated livestock wastewater on the accumulation characteristic of ARGs in the farmland soil: a case study in Hohhot, China.

Irrigation with treated livestock wastewater (TWW) is a promising strategy for reusing resources. However, TWW irrigation might introduce antibiotic resistant genes (ARGs) into the soil, posing environmental risks associated with antibiotic resistance. This study focuses on investigating the influence of irrigation amounts and duration on the fate of ARGs and identifies key factors driving their changes. The results showed that there were 13 ARGs in TWW, while only 5 ARGs were detected in irrigated soil. That is some introduced ARGs from TWW could not persistently exist in the soil. After 1-year irrigation, an increase in irrigation amount from 0.016 t/m2 to 0.048 t/m2 significantly enhanced the abundance of tetC by 29.81%, while ermB and sul2 decreased by 45.37% and 76.47%, respectively (p < 0.01). After 2-year irrigation, the abundance of tetC, ermB, ermF, dfrA1, and total ARGs significantly increased (p < 0.05) when the irrigation amount increased. The abundances of ARGs after 2-year irrigation were found to be 2.5-34.4 times higher than 1 year. Obviously, the irrigation years intensified the positive correlation between ARGs abundance and irrigation amount. TetC and ermF were the dominant genes resulting in the accumulation of ARGs. TWW irrigation increased the content of organic matter and total nitrogen in the soil, which affected microbial community structure. The changes of the potential host were the determining factors driving the ARGs abundance. Our study demonstrated that continuous TWW irrigation for 2 years led to a substantial accumulation of ARGs in soil.

Soil Water Movement and Groundwater Recharge Under Different Land Uses in a Flood-Irrigated Area.

The water shortage in agriculture area in China requires to reduce the consumption of excessive water in flood irrigation. Therefore, the dynamics of soil water regime is needed to investigate and water-saving irrigation is necessary to alleviate water shortage. This study investigated the impact of flood irrigation on soil water movement and recharge to groundwater in the Yellow River irrigation area of Yinchuan Plain, China. Combining comprehensive field observation, stable isotopic techniques and water balance simulation, we described the soil water mechanism in vadose zone covered with bare soil in 2019 and planted with maize in 2020. The soil layers affected by precipitation infiltration and evaporation were mainly 0-50 cm, while the soil influenced by irrigation was the entire profile in the mode of piston flow. The maize root took up the soil water up to the depth of 100 cm during the tasseling period. The infiltration and capillary rise in 2020 were similar with those in 2019. However, the total deep percolation was 156.5 mm in 2020 which was about 50% of that in 2019 because of the maize root water uptake. The leakage of ditch water was the major recharge resource of groundwater for the fast water table rise. Precise irrigation is required to minimize deep percolation and leakage of ditch water and reduce excessive unproductive evapotranspiration. Therefore, understanding the soil water movement and groundwater recharge is critical for agricultural water management to improve irrigation efficiency and water use efficiency in arid regions.

Cleaner tillage and irrigation options for food-water-energy-carbon synergism in wheat-maize cropping systems.

The conventional wheat-maize systems in the North China Plain are energy and water intensive with high carbon emissions. It is imperative to find cleaner production technologies for sustainable food-water-energy-carbon synergism. Here, a three-year field experiment was performed to explore the effects of two tillage modes and four irrigation regimes during wheat season on crop yield, economic profile, water use efficiency, energy utilization, and carbon footprint in typical wheat-maize cropping systems in the North China Plain. Pre-sowing irrigation resulted in the lowest crop yield and benefit profile. Pre-sowing + anthesis irrigation decreased economic benefit and water use efficiency with higher carbon footprint. Pre-sowing + jointing + anthesis irrigation led to the greatest energy consumption and greenhouse gas emissions. However, pre-sowing + jointing irrigation increased yield by 2.3-8.7%, economic benefit by 4.0-11.1%, water use efficiency by 7.4-10.9%, and net energy by 6.5-12.0% but reduced carbon footprint by 9.8-14.3% compared to pre-sowing + anthesis irrigation and pre-sowing + jointing + anthesis irrigation. The corresponding metrics in rotary tillage improved by 9.6%, 13.9%, 7.0%, and 14.2%, respectively, relative to subsoiling, whereas carbon footprint decreased by 12.4-17.2%. Besides, rotary tillage coupled with additional jointing irrigation obtained the highest value based on a Z-score method, which was recommended as a cleaner management practice to improve benefit return and water use efficiency with lower energy consumption and carbon footprint. This work provides valuable insights into food-water-energy-carbon nexus for ensuring food security and achieving environmental sustainability in the wheat-maize cropping systems.

The water-energy-food-ecosystem nexus in the Danube River Basin: Exploring scenarios and implications of maize irrigation.

The Water-Energy-Food-Ecosystem (WEFE) nexus concept postulates that water, energy production, agriculture and ecosystems are closely interlinked. In transboundary river basins, different sectors and countries compete for shared water resources. In the Danube River Basin (DRB), possible expansion of agricultural irrigation is expected to intensify water competition in the WEFE nexus, however, trade-offs have not yet been quantified. Here, we quantified trade-offs between agriculture, hydropower and (aquatic) ecosystems in the DRB resulting from maize irrigation when irrigation water was withdrawn from rivers. Using the process-based hydro-agroecological model PROMET, we simulated three maize scenarios for the period 2011-2020: (i) rainfed; (ii) irrigated near rivers without considering environmental flow requirements (EFRs); (iii) irrigated near rivers with water abstractions complying with EFRs. Maize yield and water use efficiency (WUE) increased by 101-125 % and 29-34 % under irrigation compared to rainfed cultivation. Irrigation water withdrawals from rivers resulted in moderate to severe discharge reductions and, without consideration of EFRs, to substantial EFR infringements. Annual hydropower production decreased by 1.0-1.9 % due to discharge reductions. However, the financial turnover increase in agriculture (5.8-7.2 billion €/a) was two orders of magnitude larger than the financial turnover decrease in hydropower (23.9-47.8 million €/a), making water more profitable in agriculture. Irrigation WUE was highest for EFR-compliant irrigation, indicating that maintaining EFRs is economically beneficial and that improving WUE is key to attenuating nexus water competition. Current maize production could be met on the most productive 35-41 % of current maize cropland under irrigation, allowing 59-65 % to be returned to nature without loss of production. Maize priority areas were on fertile lowlands near major rivers, while biodiversity priority areas were on marginal cropland of highest biodiversity intactness. Our quantitative trade-off analysis can help identifying science-based pathways for sustainable WEFE nexus management in the DRB, also in light of climate change.

Water rights reform and water-saving irrigation: evidence from China.

As a market-based water resource management, the water rights reform (WRR) will allocate water rights to water users and allow water users to trade water rights, which can realize the reallocation across water users. In this context, the adoption of water-saving irrigation (WSI) is an important technical form to adapt to the reform. Based on this, this paper studies the impacts of the WRR on WSI using the difference-in-differences (DID) strategy. The results show that the WRR could increase the land area for WSI by an average of 13.63%. The WRR could promote the expansion of high-efficiency irrigation mainly because the WRR could promote the expansion of spray and drip irrigation areas, and micro-irrigation land areas, which are high-efficiency water-saving irrigation technologies. In addition, the WRR also could improve agricultural production by increasing agricultural water productivity and planting area (including the sown area of grain crops and cash crops), but the WRR does not reduce agricultural water extraction. Therefore, the WRR could increase agricultural production without increasing agricultural water extraction.

Assessment of heavy metal accumulation and health risk in three essential edible weeds grown on wastewater irrigated soil.

The main problem facing Egypt recently is the shortage of available water resources. Therefore, farmers resort to use wastewater for irrigation. So, the present work aims to assess the impacts of wastewater irrigation on the productivity of three edible weeds (Cichorium endivia, Sonchus oleraceous and Beta vulgaris) and its effect on the nutritional value of plants and its risk on human health. This study will focus on Shibin Al Kanater region, and the physicochemical characteristics of drainage water, canal water, drainage water-irrigated soils and canal-irrigated soils were estimated. The vegetative and traits of edible weeds were determined including their photosynthetic pigments, organic and inorganic nutrients content, and heavy metals content. The health risk index (HRI) associated with consumption of polluted plants was created using the estimated exposure factor of a crop to the oral reference dosage of the toxic metal. The main results showed that biomass productivity of S. oleraceous, B. vulgaris and C. endivia increased due to drainage water irrigation with increasing percentage as 27.9, 19.6, and 19.1%, respectively. Irrigation with drainage water significantly increased the photosynthetic pigments of edible weeds. Irrigation with drainage water increased carbohydrate content, crude protein, total soluble sugar, and gross energy in all studied weeds. C. endivia, S. oleraceus and B. vulgaris plants irrigated with canal and drainage water could accumulate Fe, Zn, Cu, and Co in their roots. C. endivia, S. oleraceus and B. vulgaris plants irrigated with canal water indicated HRI more than the unit for Mn, Cu, Pb, and Cd. This research advises that regulation be put in place to prohibit irrigation using untreated drainage and to restrict the discharge of industrial, domestic, and agricultural wastewater into irrigation canals.

Changes in phytochemical properties and water use efficiency of peppermint (Mentha piperita L.) using superabsorbent polymer under drought stress.

Water consumption management and the application of advanced techniques in the agricultural sector can significantly contribute to the efficient utilization of limited water resources. This can be achieved by improving soil texture, increasing water retention, reducing erosion, and enhancing seedling germination through the use of superabsorbent polymers. This study aimed to investigate the effect of Aquasource superabsorbent (AS) on the morphological characteristics, phytochemical properties, antioxidant content, and water use efficiency of peppermint. It was conducted under different irrigation management and using different superabsorbent levels. Therefore, a 3 × 4 factorial design was used to determine the effects of irrigation intervals (2-, 4-, and 6-day) and different levels of AS amount (zero [control], 0.5, 1, and 2 wt%). The effects of these factors on various parameters (morphological characteristics, essential oil percentage, nutrient, protein, proline, carotenoid, antioxidant, and chlorophyll content, leaf area index, relative water content, and water use efficiency [WUE]) were evaluated. The results showed that morphological characteristics and essential oil percentage decreased significantly under drought stress (increasing the irrigation intervals). However, the addition of 0.5 (wt%) AS improved plant growth conditions. Increasing the amount of superabsorbent used to 1 and 2 (wt%) decreased the measured traits, which indicates the creation of unsuitable conditions for plant growth. AS application improved the growth of the root more than the leaf yield of peppermint. A 0.5 (wt%) addition of AS resulted in root length increases of 3, 13, and 15%, respectively, at irrigation intervals of 2, 4, and 6 days, respectively. Additionally, at 0.5 (wt%) AS, root weight increased by 8, 15, and 16% in 2-, 4-, and 6-day irrigation intervals, respectively. Also, the height of the plant increased by 3, 5, and 17% at 2-, 4-, and 6-day irrigation intervals when 0.5 (wt%) of AS was used compared to the control. As well, essential oil percentage increased by 2.14, 2.06, and 1.63% at 2-, 4-, and 6-day irrigation intervals. The nutrient and protein contents decreased as irrigation intervals and AS usage increased, indicating a similar trend. However, compared with the control, the addition of 0.5 (wt%) of AS resulted in some improvements in nutrients and protein. The highest WUE (3.075 kg m-3) was attained in the 4-day irrigation interval and 1 wt% AS addition. This was followed closely by the 2-day irrigation interval with 1 wt% AS addition at 3.025 kg m-3, and the 4-day irrigation interval with 0.5 wt% AS addition, which reached 2.941 kg m-3. Overall, the use of AS in appropriate amounts (0.5 wt%) can reduce water consumption and enhance essential oil yield and WUE in peppermint cultivation in water-scarce arid and semi-arid regions.

Industrial wastewater irrigation increased higher heavy metals uptake and expansins, metacaspases, and cystatin genes expression in Parthenium and maize.

Industrial wastewater irrigation of agricultural crops can cause a lot of environmental and health problems in developing countries due to heavy metals deposition in agricultural soils as well as edible plant consumption by human beings. Therefore, this study was conducted to find out the heavy metals concentration in industrial wastewater and soil irrigated with that wastewater. In addition, the aim was to determine the impact of industrial wastewater irrigation on Parthenium hysterophorus and Zea mays genes involved in growth improvement and inhibition. For this purpose, plant samples from agriculture fields irrigated with wastewater from Hattar Industrial Estate (HIE) of Haripur, Pakistan, and control plants from non-contaminated soil irrigated with tape water were collected after 15 and 45 days of germination. Heavy metals concentration in the collected plant samples, wastewater, and soil was determined. The results revealed that the soil of the sample collection site was predominantly contaminated with Cr, Pb, Ni, Cu, Co, Zn, and Cd up to the concentrations of 38.98, 21.14, 46.01, 155.73, 12.50, 68.50, and 7.01 mg/kg, respectively. The concentrations of these heavy metals were found to surpass the permissible limit in normal agricultural soil. Expansins, cystatins (plant growth enhancers), and metacaspases (plant growth inhibitor) gene expression were studied through reverse transcription polymerase chain reaction. The results showed that the expression of these genes was higher in samples collected from wastewater-irrigated soils as compared to control. The expression of these genes was observed in 45 days old samples, 15 days old samples, and control. Taken together, this study suggests the use of Parthenium and maize for phytoremediation and that they should not be used for eating purposes if irrigated with industrial wastewater.

Improvement of the estimation of the infiltration function in surface irrigation systems.

Surface irrigation systems are widely used on the North China Plain. The design of surface irrigation systems can be improved by developing simulation models including the advanced trajectory, recession trajectory, and infiltration time. Therefore, the objectives of this study were as follows: (1) to evaluate different models to simulate the advanced and recession trajectories, (2) to propose a new method that reduces the required observation data for estimating the infiltration time, and (3) to evaluate the accuracy of the proposed infiltration function based on the modified infiltration time function. Field experiments were conducted. The results indicated that the power function can represent the advanced and recession trajectories well. A modified function that describes the infiltration time has a high correlation and accuracy with the measured data and can be used to estimate the infiltration time. The proposed infiltration function based on the modified infiltration time function is accurate and can be used to estimate the infiltration function.

Micro-nano oxygenated irrigation improves the yield and quality of greenhouse cucumbers under-film drip irrigation.

To study the influence mechanism of micro-nano oxygenated irrigation (MNOI) on greenhouse fruit cucumber in arid and semi-arid cold regions, the yield and quality of greenhouse fruit cucumber were evaluated and verified based on 2 years of observation data. Taking fruit cucumber in Ningxia solar greenhouse as the research object, three dissolved oxygen (DO) levels of MNOI (DO; 6, 7.5, and 9 mg L-1, O1, O2, and O3, respectively) and non-oxygenated irrigation (CK, 4 mg L-1) were set up as the control treatment. Through comparative design, the influence mechanism of different levels of aerobic irrigation on the yield and quality of greenhouse fruit cucumber was studied. The main indicators of fruit cucumber yield and quality increased with dissolved oxygen in irrigation water from 4 to 9 mg L-1. In spring-summer (autumn-winter), compared with CK, the leaf area index (LAI) and net photosynthetic rate (A) increased by 28.83% (28.77%) and 44.90% (35.00%), respectively, and Vitamin C, soluble protein, soluble sugar, soluble solids and total acid content increased by 100.00% (51.88%), 37.78% (61.11%), 34.17% (54.17%), 37.07% (78.72%) and 26.92% (30.67%) respectively, while nitrate content decreased by 44.88% (51.15%), and dry matter accumulation (DMA), soil respiration rate (SRR), microbial carbon (MC), and microbial nitrogen (MN) increased by 49.81% (127.25%), 55.22% (110.34%), 117.50% (90.91%) and 70.37% (74.42%) respectively, and yield, irrigation water use efficiency (IWUE) and soil oxygen content (SO) increased by 22.47% (28.04%), 22.39% (28.05%) and 33.21% (35.33%) respectively. A model of DO in irrigation water and SO was established and the applicability of the model was verified with an average relative error of 2% (less than 5%). MNOI increased SO and soil enzyme activity, enriched soil microorganisms, improved soil microenvironment, promoted water nutrient uptake and growth of root system, increased chlorophyll, photosynthesis and DMA, which improved fruit cucumber yield and quality, and the better DO concentration in irrigation water is 9 mg L-1. The research results provide theoretical support for regulating soil water, fertilizer and air environment, and at the same time, provide feasible ways to improve the quality and efficiency of crops in arid and semi-arid cold regions.

Smart control of soil water and salt content for improving irrigation management of tomato crop field: Kairouan area.

A good assessment of soil water and salt content is required for sustainable irrigation with brackish/saline water. The use of the Internet of Things (IoT) has been initiated for the tomato crop (Savera variety) as part of the PRIMA MEDITOMATO project. An experiment was carried out between February and June 2022 at a farmer's site. For continuous soil water and salt content assessment, TEROS (11/12) probes were implemented at depths of 0, 10, 20, 30, and 60 cm. The data logging process was performed by a ZL6 device and delivered by the ZENTRA Cloud web application (METER GROUPE Company). For the accuracy of the introduced sensors, calibration tests were first processed. Results of the calibration of the probes in the laboratory and in situ showed linear relationships between the humidity values measured by ZL6 (θZL6) and those determined by the gravimetric method, with high correlation coefficients (R2) of 0.86 and 0.96, respectively. There were also strong linear relationships between the ECbulk(ZL6) and the ECe measured on saturated paste extract with high correlation coefficients (R2) of 0.96 and 0.95. Corrected data, according to the determined linear regression equations, present the real-time assessment of soil water and salt content over the entire growth stage of tomatoes. The results of this monitoring showed that soil water content remained close to its status at field capacity (32%) at the beginning of the assessment and increased with the intensification of irrigation, reaching 46 and 54% at 20 and 30 cm, respectively, around mid-April. The salinity level was greater with depth. Indeed, it was low in topsoil with the increase in irrigation frequency and higher at 30 and 60 cm toward the end of the tomato cycle. According to this study, real-time data given by ZENTRA Cloud allows us to adjust irrigation management on time.

Optimizing irrigation strategies for sustainable crop productivity and reduced groundwater consumption in a winter wheat-maize rotation system.

Inefficient irrigation practices have hindered crop yields, wasted irrigation water resources, and posed threats to groundwater levels and agricultural sustainability. This study evaluated different irrigation strategies for a winter wheat-summer maize rotation system to identify sustainable practices for maintaining yields while reducing groundwater depletion. A two-year field experiment was conducted, implementing three optimized irrigation strategies during the winter wheat season: I-4 (irrigated until the soil water content (SWC) of the 40 cm soil layer reaches 60% of field capacity (FC), I-6 (irrigated until the SWC of the 60 cm soil layer reaches 80% FC), and a rainfed (R) as control. Irrigation was repeated when the SWC dropped to the specified level. No irrigation level was used during the summer maize season, except for irrigation after sowing that ensuring the normal emergence of maize. WHCNS (Water Heat Carbon Nitrogen Simulator) model was developed to simulate soil water dynamics, field water consumption, and yield of both crops. The result indicated WHCNS model accurately simulated water dynamics, consumption, and grain yield. Compared to R treatment, the I-4 treatment significantly increased annual crop yield by 19.83%-28.65% (p < 0.05), while maintaining similar crop water productivity. Furthermore, the I-4 treatment achieved comparable yields to the I-6 treatment, but with a 33.91% reduction in irrigation water use, resulting in a 33.46% increase in crop water productivity and a 90.53% increase in irrigation water productivity. From a sustainable perspective, the I-4 treatment effectively reduced field water losses and maintained relatively high soil water storage, particularly in the topsoil, which was beneficial for the early growth of subsequent crops. The R treatment greatly contributed to groundwater recharge when precipitation was sufficient, while it led to severe yield losses. Overall, under the condition of annual rotation planting systems, the I-4 treatment sustainably maintained yields with less irrigation, decreasing groundwater consumption. This approach could conserve regional water resources and groundwater table while upholding agricultural productivity and achieving system sustainable water use.

Impact analysis of moisture stress on growth and yield of cotton using DSSAT-CROPGRO-cotton model under semi-arid climate.

Adequate soil moisture around the root zone of the crops is essential for optimal plant growth and productivity throughout the crop season, whereas excessive as well as deficient moisture is usually detrimental. A field experiment was conducted on cotton (Gossipium hirsuttum) with three water regimes (viz. well-watered (control); rainfed after one post-sowing irrigation (1-POSI) and rainfed after two post-sowing irrigations (2-POSI)) in main plots and application of eight osmoprotectants in sub plots of Split plot design to quantify the loss of seed cotton yield (SCY) under high and mild moisture stress. The DSSAT-CROPGRO-cotton model was calibrated to validate the response of cotton crop to water stress. Results elucidated that in comparison of well watered (control) crop, 1-POSI and 2-POSI reduced plant height by 13.5-28.4% and lower leaf area index (LAI) by 21.6-37.6%. Pooled analysis revealed that SCY under control was higher by 1,127 kg ha-1 over 1-POSI and 597 kg ha-1 than 2-POSI. The DSSAT-CROPGRO-cotton model fairly simulated the cotton yield as evidenced by good accuracy (d-stat ≥ 0.92) along with lower root mean square error (RMSE) of ≤183.2 kg ha-1; mean absolute percent error (MAPE) ≤6.5% under different irrigation levels. Similarly, simulated and observed biomass also exhibited good agreement with ≥0.98 d-stat; ≤533.7 kg ha-1 RMSE; and ≤4.6% MAPE. The model accurately simulated the periodical LAI, biomass and soil water dynamics as affected by varying water regimes in conformity with periodical observations. Both the experimental and the simulated results confirmed the decline of SCY with any degree of water stress. Thus, a well calibrated DSSAT-CROPGRO-cotton model may be successfully used for estimating the crop performance under varying hydro-climatic conditions.