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Abstract Irrigated agriculture plays a major role in the livelihoods of nations all over the world and with the agricultural water use sector being the largest of all water use sectors, there have been increased expectations that the sector should increase efficiency. Irrigation efficiency should be assessed by applying a water balance and the purpose of an irrigation system is to apply the desired amount of water, at the correct application rate and uniformly to the whole field, at the right time, with the least amount of nonbeneficial water consumption (losses), and as economically as possible. The fraction of the water abstracted from the source that can be utilized by the plant, can be called the beneficial water use component, and optimized irrigation water supply is therefore aimed at maximizing this component. A water use framework that covers four levels of water management infrastructure: the water source, bulk conveyance system, the irrigation scheme, and the irrigation farm can be used to improve irrigation efficiency. The water balance approach can be applied at any level, within defined boundaries, or across all levels to assess performance within the whole Water Management Area.

Abstract Surface irrigation type is one of the most widely used in the world due to its low cost investment. However it is complex method of applying water to soil, because of extreme difficult to achieve good control over the highly variable nature of the movement of water across a soil surface and its infiltration into the soil over a season. This study is attempted to optimize furrow irrigation decision variables at Wonji Shoa sugar estate using field experiment and two simulation models. The field data of experimental site was measured as input for models and simulated using the SIRMOD software and WinSRFR software package. Furrow lengths of 32 m, 48 m and 64 m, slopes of 0.05%, 0.075% and 0.1%and flow rates of 3 l/sec, 4 l/sec and 5 l/sec were analyzed with three replication using volume balance method and two simulation models. The study found optimum decision variables that gave maximum application efficiency and distribution uniformity were slope of 0.1%, furrow length of 32 m and inflow rate of 4 l/sec at cut-off time of 15.79 min. Thus, to improve the performance of furrow irrigation practice, optimal furrow length, inflow rates and cut-off time found by this study should be adopted. Findings from the study would serve as a source of information for use by policy makers and planners during the design and Operation of irrigation development programs. It does not focus on yield related optimization. So, it is open for the future research to conduct yield related optimization of the decision variables.

Groundwater resources are the most reliable freshwater supply in arid regions where many aquifers face dramatic depletion due to natural and anthropogenic causes. The annual average rate of decline of groundwater level is about 1.65 m. This research focuses on an aquifer that suffers from severe groundwater stress, and it aims to identify the main causes of the stress and to understand the effects of climate change and human activity. Monthly data on groundwater level, precipitation, temperature, river discharge, evapotranspiration, soil moisture, and vegetation cover were collected from 2000 to 2020. The results indicate that declining groundwater levels mainly resulted from the expansion of vegetation cover rather than changes in hydro-climatic variables. Finally, this work highlights how significant financial investment in improving irrigation efficiency in the absence of socio-economic plans, education, awareness, and monitoring programmes unproductively resulted in the expansion of agricultural activities rather than preserving groundwater storage. [ABSTRACT FROM AUTHOR]

In this study, a new method for determining the depth of frozen soil, Impulse Response Time Domain Reflectometry, is discussed. This method uses the principle of impedance measurement and the law of time–frequency domain convolution to convert the frequency-domain reflection signal into a time-domain signal and accurately determines the soil freezing front by measuring the difference between the impedance of frozen soil and unfrozen soil. The advantage of this method is that it solves the problems of small bandwidth, long rising edge time, and large measurement errors in the traditional TDR method to effectively improve the measurement accuracy of the soil-freezing front. Under laboratory conditions, soils of different textures (sand, loess, black soil, and red soil) were selected for experimental determination, and the results showed that compared with the traditional TDR method, the RMSE of the I-TDR method was small, and the method was applicable under different soil texture conditions, which could provide a new method for monitoring frozen soil in cold areas. In addition, the application of this method has important guiding significance for improving the efficiency of winter irrigation water, especially for guiding agricultural production, farmland irrigation, drainage engineering construction, meteorological frozen soil monitoring, and other aspects in cold and arid areas. [ABSTRACT FROM AUTHOR]

Irrigated turfgrass is a major crop in urban areas of the drought-stricken Western United States. A considerable proportion of irrigation water is wasted through the use of conventional sprinkler systems. While smart sprinkler systems have made progress in reducing temporal mis-applications, more research is needed to determine the most appropriate variables for accurately and cost-effectively determining spatial zones for irrigation application. This research uses data from ground and drone surveys of two large sports fields. Surveys were conducted pre-, within and towards the end of the irrigation season to determine spatial irrigation zones. Principal components analysis and k-means classification were used to develop zones using several variables individually and combined. The errors associated with uniform irrigation and different configurations of spatial zones are assessed to determine comparative improvements in irrigation efficiency afforded by spatial irrigation zones. A determination is also made as to whether the spatial zones can be temporally static or need to be re-determined periodically. Results suggest that zones based on spatial soil moisture surveys and simple observations of whether the grass felt wet or dry are better than those based on NDVI, other variables and several variables in combination. In addition, due to the temporal variations observed in spatial patterns, ideally zones should be re-evaluated periodically. However, a less labor-intensive solution is to determine temporally static zones based on patterns in soil moisture averaged from several surveys. Of particular importance are the spatial patterns observed prior to the start of the irrigation season as they reflect more temporally stable variation that relates to soil texture and topography rather than irrigation management. [ABSTRACT FROM AUTHOR]

Improving water and fertilizer use efficiency in arid and semi-arid regions can not only promote the sustainable development of regional crop production, but also effectively meet the challenges of future global water shortage and food security. Bubbled-root irrigation is a new water-saving irrigation technology developed for arid and semi-arid areas. It not only has the characteristics of precision irrigation (improving water and fertilizer utilization and irrigation efficiency), but also has the advantage of not being easily blocked. In this study, the infiltration capacity, wetting front transport characteristics, water and nitrogen transport, and transformation characteristics of Bubbled-root Irrigation under water and fertilizer coupling conditions were investigated in the arid region of Northwest China. The results showed that under the same infiltration time, the higher the fertilizer concentration, the greater the cumulative infiltration and wetting front (horizontal, vertical upward, and vertical downward wetting front) transport distance. Based on the results, a mathematical model with cumulative infiltration or wetting front as the dependent variable, fertilizer concentration and infiltration time as independent variables was constructed. The model has high reliability (The relative deviation between the fitted value and the measured value is within ± 10%), and can be used to guide the layout of emitters in the field and crop production. Under the same infiltration time, the higher the fertilizer concentration, the higher the content of water, ammonium nitrogen, and nitrate nitrogen in the same soil node. For example, the soil water content of C = 12, 35, 60 g L−1 was 8.35%, 14.37%, 23.31% higher than that of C = 0 g L−1 at 10 cm horizontal and 40 cm vertical to the emitter. At the soil depth of 40 cm, the soil mass water content is 21.46%, 17.06%, 15.50%, and 10.37% at the end of irrigation and 1, 3, and 5 d of redistribution. The contents of ammonium nitrogen in soil are 228.13, 215.43, 183.16, and 116.43 mg kg−1 at the end of irrigation, 3, 5, and 10 d of redistribution, respectively. Redistribution of 5–10 d, soil NH 4 + N content decreased significantly. Distribution of 1–10 d, soil NO 3 - N content showed varying degrees of increase. The research results are helpful to promote the application of spring root irrigation in the world, improve the utilization efficiency of water and fertilizer, and provide a new way to alleviate the pressure of water resources and food security. [ABSTRACT FROM AUTHOR]

Copyright of Ecosistemas y Recursos Agropecuarios is the property of Universidad Juarez Autonoma de Tabasco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pakistan faces water scarcity and high operational costs for traditional irrigation systems, hindering agricultural productivity. Solar-powered irrigation systems (SPIS) can potentially provide a sustainable and affordable solution, but face technical, financial and policy barriers to adoption. A comprehensive study is needed to examine feasibility and identify barriers. Therefore, a comprehensive review study is conducted to identify the potential for solar irrigation, key issues and challenges related to its implementation in Pakistan. The analysis is based on published studies, technical reports and a survey of solar-powered drip irrigation systems. The use of SPIS in Pakistan is becoming a cost-effective and sustainable option for irrigation, particularly in remote and off-grid areas. However, these systems also have their challenges, such as high initial costs, maintenance and repairs, limited access to spare parts, lack of government policies and regulations, lack of technical expertise, lack of financing options and social acceptance. The most pressing issue is the risk of groundwater exploitation by using SPIS. Based on the analysis of the energy and water situation in Pakistan, it is important to sustainably use both solar energy and groundwater resources, through the implementation of effective management strategies and policies. With the right policies and investment in research and development of SPIS and groundwater, farmers can benefit by increasing crop yields, conserving water resources, reducing the cost of energy, increasing productivity and improving the standard of living and access to electricity in remote and off-grid areas. It is recommended that the adoption of solar energy be promoted to run high efficiency irrigation systems (HEIS) with urgent capacity improvement among farmers, advisors and system installers to sustainably manage water resources in SPIS. This would not only help to reduce the consumption of fossil fuels and associated environmental impacts, but also increase farmers' income and reduce their operational costs. Moreover, the use of SPIS can improve crop yields, leading to food security and poverty reduction. Thus, the government and policymakers should consider implementing policies and incentives to encourage the large-scale adoption of solar energy in the agricultural sector. [ABSTRACT FROM AUTHOR]

Despite the great number of models developed in research projects, only a small percentage have been successfully transferred to the productive sector. The PRIMA programme supported by Horizon 2020, the European Union Framework Programme for Research and Innovation, aims to reverse this situation. The SUPROMED project funded by PRIMA sought to develop an online platform composed of several models adapted to the requirements of end users for increasing the economic and environmental sustainability of Mediterranean agricultural systems. MOPECO, in its research version, was designed to maximize the profitability of irrigated farms in water-scarce regions. A simplified version of this model (MOPECO irrigation scheduling) was included in the SUPROMED platform for improving irrigation efficiency, providing farmers with a useful irrigation scheduling software. This paper shows the approach to adapt and transfer MOPECO to the productive sector. The tool was validated in three different demosite areas across the Mediterranean, involving local stakeholders in the design, validation, and dissemination of the software. The simplified tool reached similar or higher yields than farmers using less water. Thus, the average water saved was around 16%, while the average yield increased around 10% in the plots located in the three demosites of the project (Eastern Mancha in Spain, Bekaa valley in Lebanon, and Sidi Bouzid in Tunisia). This fact decreased the water footprint and increased the profitability of farms. The high applicability of the tool has generated interest among many technicians, farmers, and advisory enterprises. Furthermore, regional and national governmental extension services have shown interest in spreading the use of the tool across their territories, validating the methodology used for adapting and transferring a scientific model to the productive sector. [ABSTRACT FROM AUTHOR]

Objective: To evaluate water consumption in ornamental plants (geranium, gazania and petunia) in two substrates with different particle sizes (fine and coarse) of tezontle and peat moss, through a suction irrigation system, which uses porous capsules as irrigation emitters. Design/methodology/approach: The experimental design was in complete randomized blocks, with six treatments (three ornamental species and two substrates) with four repetitions (24 experimental units). The first mixture contains fine substrate (composed of tezontle with particle size less than 0.4 mm) and peat moss, in a 1:2 v/v ratio; the second mixture presents coarse substrate (composed of tezontle with particle size between 0.4-0.6 mm) and peat moss, 1:1 in v/v. Results: In water consumption, there are significant differences by ornamental species and type of substrate, where the irrigation system has the ability to self-regulate. The highest water consumption was in petunia in the coarse substrate (which has a higher proportion of peat moss in its composition). Limitations on study/implications: With use in protected agriculture, rural and urban orchards, gardens, walls and green roofs and research purposes. Findings/Conclusions: The suction irrigation system through porous capsules has the capacity to continuously supply the water demanded by the plant-substrate-atmosphere system. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ever-rising trend of nitrate leaching from the agricultural production systems is a major risk to the contamination of ground- and surface-waters and should be addressed. But so far, there has been no study on the reduction of nitrate leaching from saffron fields through intercropping. Saffron growers can make a sustainable use of the saffron inter-row spaces through the strategy of winter-wheat/saffron base intercropping system to reduce nitrate leaching. During four years of study, in a set of lysimeters, effects of two cropping systems (saffron mono-cropping and saffron–wheat intercropping), application of two sources of nitrogen (organic cow manure and chemical granular urea) and four irrigation regimes [40, 60, 80, and 100% of the standard crop evapotranspiration (ETc)] on plant nitrogen and phosphorus uptake, nitrogen leaching and nitrogen and phosphorus efficiencies were investigated. The optimum irrigation regime was experienced at 60% ETc (with irrigation application efficiency of 60%, equivalent to 100%ETc) where the highest saffron and wheat nutrient (nitrogen and phosphorus) uptake, nutrient (nitrogen and phosphorus) harvest indices, nutrient acquisition and use efficiencies, corm, saffron, and grain yields and lowest nitrogen loss was achieved. Moreover, manure application indicated 12, 42, 50 and 46% lower amounts of drained water, leachate nitrate nitrogen concentration, total leached nitrogen and N losses (other than N leaching), respectively, in comparison to the urea source of nitrogen showing the lower risk of groundwater nitrate pollution. Manure application showed 9, 8 and 9% increase in the concentration of corm nitrogen, phosphorus and protein, respectively, in comparison to urea application treatment. Saffron corm and stigma yields, irrigation and economic water productivities, corm nitrogen use efficiency and saffron-plant-nitrogen-acquisition efficiency in manure application surpassed respectively by 21, 25, 20, 17, 39 and 49% compared with the chemical source of nitrogen. Intercropping showed 10, 11, 23 and 64% lower amounts of drained water, nitrate concentration in drainage water, seasonal leached nitrate and N losses (other than N leaching), respectively compared to saffron sole cropping which reduces the risk of groundwaters nitrate contamination. For all the experimental treatments, empirical regression models were derived for estimation of seasonal leached nitrate based on the seasonal drained water. Intercropping saffron with winter wheat, application of organic cow manure and adopting irrigation regime of 60% ETc is an innovative system of saffron production which mitigates the risk of groundwater nitrate contamination and increases irrigation and economic water productivities. Saffron growers can make sustainable and clean use of the inter-row spaces of the saffron crop to grow winter wheat in order to obtain higher economic water productivity and lower groundwater nitrate pollution, and it is highly recommended to maintain a sustainable environment. [ABSTRACT FROM AUTHOR]

Water-saving irrigation technology has been studied for many years, but due to insufficient investment in research and development of irrigation equipment, it cannot be effectively promoted and applied. In order to improve the water use efficiency of farmland irrigation, the automatic monitoring of groundwater level change, soil moisture change, and crop seasonal growth status is realized in the ditch or pump well irrigation area. An intelligent measuring terminal for water-saving irrigation based on RN2026 microcontroller is developed. The terminal uses the coefficient of "water conversion by electricity" to automatically convert the water consumption of farmers and uses the price mechanism of water rights to affect farmers' water conservation. In combination with changes in groundwater level, crop evapotranspiration, and dynamic changes in soil moisture, precision irrigation strategies are automatically generated to guide farmers to use water rationally. Through the function and performance experiments, the results show that the error of the coefficient of "water conversion by electricity" is less than 1%, the error of electric energy measurement is less than 0.5%, the estimated value of average water use right per unit arable area is consistent with the actual value, and the predicted value of daily average soil moisture change is consistent with the measured value. The equipment has strong adaptability to the environment, high measurement accuracy, strong data processing ability, low cost, and other characteristics. It meets the requirements of water-saving irrigation technology in practical applications and has good promotion and application value. [ABSTRACT FROM AUTHOR]

Water security is a hot topic all over the world, due to global warming, climate change, natural calamities such as droughts and floods, overuse of water, and other factors. Water issues have been scientifically investigated from several perspectives, namely institutional, economic, social, environmental, managerial, and technological. However, the technological aspects of irrigation and water supply for smallholder farmers in the Mediterranean region have not been adequately addressed. This paper explores irrigation and water supply technologies for smallholder farmers in the selected Mediterranean countries (Egypt, Malta, Morocco, and Portugal). The methods of analysis are literature review, fieldwork, and observation. The literature survey reveals that Mediterranean countries share many common features in terms of climate, water and land resources, and development issues. Nevertheless, the selected countries in the Mediterranean region (Egypt, Malta, Morocco, and Portugal) differ in terms of type of crops, water management regulations, labor force availability, financial sustainability, and economic approaches. These remarks signal the need for applying a specific approach in selecting a technology for irrigation and water supply according to the regional context. Additionally, the financial and economic perspectives of the three key technologies (i.e., SLECI, desalination technology, and engineering constructed wetlands) require further analysis. [ABSTRACT FROM AUTHOR]

The SIRMOD and WinSRFR models were used to model and assess the irrigation performance under continuous and surge irrigation strategies with two furrow lengths of 70 m and 90 m and stream sizes of 0.4 l/s and 0.6 l/s for each length. According to the normalized root mean squared error (NRMSE) and the relative error (RE), WinSRFR had, on average, excellent accuracy in the continuous and surge irrigation for simulating advance-recession times (NRMSE: 6.15 and 4.24% for advance time, and 2.20 and 5.20% for recession time), infiltrated water depth (NRMSE: 3.37 and 6.38%), and runoff volume (RE: 6.93 and 2.57%), respectively. SIRMOD had also, on average, excellent simulation in the continuous and surge irrigation for advance-recession times (NRMSE: 3.34 and 2.45% for advance time, and 2.28 and 6.41% for recession time), infiltrated water depth (NRMSE: 2.98 and 5.27%), and runoff volume (RE: 5.31 and 17.49%), respectively. The average of irrigation application efficiency (AE), distribution uniformity (DU), deep percolation (DP), and tail-water ratio (TWR) were 61.50, 90.25, 11.75, and 26.75% in continuous irrigation, and 72.03, 94.09, 8.39, and 19.57% in surge irrigation, respectively, which shows that surge irrigation increased AE (irrigation management performance) and DU (irrigation method performance) and reduced DP and TWR compared to continuous irrigation. Moreover, longer furrow lengths increased AE and DP under both irrigation methods, while it decreased TWR and DU. However, increasing the stream size decreased AE and DP and increased TWR under both continuous and surge irrigations. The higher stream size improved DU in continuous irrigation but reduced DU in surge irrigation. The results confirmed that both SIRMOD and WinSRFR are reliable analytical tools to evaluate furrow irrigation strategies for improving irrigation management. In conclusion, this study showed that surface irrigation models could be employed in practice by irrigation engineers and practitioners to design and define the optimized furrow length and stream size in arid and semi-arid areas where efficient and high performance irrigation strategies are required to save water and reduce water loss. [ABSTRACT FROM AUTHOR]

Indus Basin Irrigation System (IBIS) in Pakistan is the backbone of agriculture in the country. The IBIS provides irrigation support to agricultural lands across the country; however, hydraulic efficiency of the water conveyance system is impacted due to seepage losses. The lining of irrigation channels is considered a potential solution for improving hydraulic efficiency. Therefore, this study explores the impact of canal lining on the hydraulic efficiency of the canals in the Punjab province of Pakistan. Overall, 14 channels/distributaries/minors (total length 226 km) were monitored in terms of hydraulic performance in different irrigation zones. Hydraulic, geometrical, and socioeconomic parameters of channel/distributaries/minors including roughness coefficient, sediments, flow velocity, wetted parameter, breaches, theft cases, bed, side slope, water surface profile, hydraulic radius, crop yield, and vegetation growth area have been experimentally observed. Obtained results have been compared with the design and pre-lining data. Ten seepage tests using the inflow -outflow method and eight seepage tests using the ponding method were conducted to estimate seepage losses. Results indicate that almost all the parameters varied from the design values. A detailed comparison of the socioeconomic parameters has been carried out. Results from seepage tests show an approximately 78% reduction in losses. [ABSTRACT FROM AUTHOR]

In regions such as the Brazilian Cerrado where water availability is low and disputes for water resources are increasing, it is important to evaluate technologies that can increase the efficiency of irrigation. In this scenario, precision irrigation has great potential. However, studies that evaluate the real benefits of precision irrigation are necessary. The present work aimed to assess the precision irrigation potential for increasing crop yield and water savings. To evaluate the possible precision irrigation benefits, two center pivots, acting over soils that had different hydro-physical characteristics, were studied. The available water in the soil (AWC) was used as a reference for irrigation management in two conditions, one considering and one disregarding soil spatial variability. In the management under homogeneous soil conditions, the lowest, the average and the highest AWC values were considered. Management under variable conditions was carried out individually for each pixel with a dimension of 25 m2 (5 × 5 m), considering its real AWC value. Also, four soybean crop sowing dates were considered in a rainy and a dry year. A specific precision irrigation module was developed in Python language to carry out the simulations. The results obtained indicated an average water savings potential of 4.5% in a rainy year and 4.3% in a dry year. The average increased yield potential was 6.4% in the rainy year and 4.0% in the dry year. [ABSTRACT FROM AUTHOR]

Using a three-infrastructures (grey, soft, and green) framework, we examined key risks to water availability and quality in the Murray-Darling Basin, Australia. These risks include increased irrigation efficiency, without a quantitative knowledge of the impact on water flow pathways, particularly return flows, growth in farm dams and floodplain harvesting, and unsustainable management of salinity. Critical to mitigating these risks are the metering, monitoring, and auditing of water flows, effective linkages between evidence and analysis, and accountability of decision-makers operating in the public interest. We contend that these approaches need to be supported by innovative risk assessments, which are fit-for-purpose under the MDB Plan, wherein the 'who, what, when and where' are assessed in relation to cumulative, systemic, and cascading risks from human actions. [ABSTRACT FROM AUTHOR]

The study was conducted in the period 2018-2020 in the Training and Experimental Base of the Department of Plant Breeding at the Faculty of Agriculture of the Trakia University - Stara Zagora on soil type typical meadow-cinnamon soil in fertilizer experience in non-irrigated and irrigated conditions. The field experience is by the method of fractional plots in four repetitions with the size of the harvest plot 15 m2 (1.80 x 8.34 m). The research factors are: irrigation (A), variety (B), fertilization rates (C) and meteorological conditions during the marketing year (E). The study was conducted with three varieties of cotton - Helius, Darmi and Isabell, with three levels of nitrogen fertilization - 80, 160, 240 and 0. The effect of irrigation on cotton productivity has been established. As a result of the conducted Polish research, it was established that the total yield of unginned cotton realized on average for the research was very good - 1,945.2 kg/ha. The average yield under irrigated conditions exceeds the yield without irrigation by 34%. The Darmi variety stands out as the most productive and promising compared to Helius and Isabell. The optimal nitrogen rate of the tested is N160. When fertilizing with N240, the yield shows a downward trend compared to N160 and this fertilization is not effective. On average for the period, at the four levels of nutritional regime, the effect of 100 m3 of irrigation water was established - 89.81 kg/ha. With the naturally coloured variety Isabel, the effect is the highest, on average for 4 levels of fertilization - 100.75 kg/ha. [ABSTRACT FROM AUTHOR]

Water is an essential resource for social and economic development. The availability of this resource is constantly threatened by the rapid increase in its demand. This research assesses current (2010–2016), short- (2017–2040), middle- (2041–2070), and long-term (2071–2099) levels of water security considering socio-economic and climate change scenarios using the Water Evaluation and Planning System (WEAP) in Vilcanota-Urubamba (VUB) catchment. The streamflow data of the Pisac hydrometric station were used to calibrate (1987–2006) and validate (2007–2016) the WEAP Model applied to the VUB region. The Nash Sutcliffe efficiency values were 0.60 and 0.84 for calibration and validation, respectively. Different scenarios were generated for socio-economic factors (population growth and increased irrigation efficiency) and the impact of climate change to evaluate their effect on the current water supply system. The results reveal that water availability is much higher than the current demand in the VUB for the period (2010–2016). For short-, middle- and long term, two scenarios were considered, "Scenario 1" (RCP 4.5) and "Scenario 2" (RCP 8.5). Climate change scenarios show that water availability will increase. However, this increase will not cover the future demands in all the sub-basins because water availability is not evenly distributed in all of the VUB. In both scenarios, an unmet demand was detected from 2050. For the period 2071–2099, an unmet demand of 477 hm3/year for "Scenario 1" and 446 hm3/year for "Scenario 2" were estimated. Because population and agricultural demands are the highest, the effects of reducing the growth rate and improving the irrigation structure were simulated. Therefore, two more scenarios were generated "Scenario 3" (RCP 4.5 with management) and "Scenario 4" (RCP 8.5 with management). This socio-economic management proved to be effective in reducing the unmet demand up to 50% in all sub-basins for the period 2071–2099. [ABSTRACT FROM AUTHOR]

Irrigation guarantee capacity is the critical factor in evaluating the development level of irrigated agriculture and is also a future development trend. It is necessary to carry out scientific planning and reasonable allocation of irrigation water resources to ensure the sustainable development of irrigated agriculture and improve the efficiency and effectiveness of water resource utilization. This study is based on remote sensing meteorological data and the principles of the Miami model and water balance. We calculated the annual irrigation water requirement and effective irrigation water, and used the ratio between the effective irrigation water and irrigation water requirement as the basis for evaluating an irrigation guarantee capability index. By using irrigation guarantee capability evaluation indicators from multiple years, we evaluated and assessed the irrigation guarantee capability in the arid region of northwest China. In addition, we analyzed three indicators (i.e., irrigation water requirement IWR, effective irrigation water EIW, and irrigation guarantee capacity index IGCI) to explore the rational allocation of water resources in the northwest arid area. IWR, EIW, and ICGI in northwest China from 2001 to 2020 were analyzed, and the average values were 379.32 mm, 171.29 mm, and 0.50, respectively. Simultaneously, an analysis was conducted on the temporal and spatial distribution of IWR, EIW, and IGCI in the northwest region of China from 2001 to 2020. The results indicated that the rainfall in the southwestern edge of the Yellow River Basin and the eastern part of the Qaidam Basin could meet the irrigation water demand. The northwest edge of the Yellow River Basin, the central Hexi Inland River Basin, most of Northeast Xinjiang, central and southeastern Xinjiang, and other regions mainly rely on irrigation to meet agricultural water requirements. The rest of the region needs to rely on irrigation for supplementary irrigation to increase crop yield. All districts in the 'Three Water Lines' area of northwest China should vigorously develop sprinkler irrigation, micro-irrigation, pipe irrigation, and other irrigation water-saving technologies and support engineering construction. Under the premise of ensuring national food security, they should reduce the planting area of rice, corn, and orchards, and increase the planting area of economic crops such as beans and tubers in the 'Three Water Lines' area. That is conducive to further reducing the agricultural irrigation quota and improving the matching degree of irrigation water resources. It provides a scientific reference for optimizing water resource allocation and improving irrigation water-use efficiency in northwest arid areas. [ABSTRACT FROM AUTHOR]

Climate change and the related temperature rise can cause an increase in evapotranspiration. Thus, the assessment of potential evapotranspiration (PET) trends is important to identify possible ongoing signals of climate change, in order to develop adaptation measures for water resource management and improve irrigation efficiency. In this study, we capitalize on the data available from a network of 46 complete meteorological stations in Sicily that cover a period of about 21 years (2002–2022) to estimate PET by the Food and Agriculture Organization (FAO) using the Penman–Monteith method at the daily time scale in Sicily (southern Italy). We then analyse the trends of PET and assess their significance by Sen's Slope and the Mann–Kendall test at multiple temporal scales (monthly, seasonal, and annual). Most of the locations do not show significant trends. For instance, at the annual timescale, only five locations have a significantly increasing trend. However, there are many locations where the monthly trend is statistically significant. The number of locations where monthly trend is significant is maximum for August, where 18 out of these 46 stations have an increasing trend. In contrast, in March, there are no locations with a significant trend. The location with the highest increasing trend of PET indicates trend slopes of 1.73, 3.42, and 10.68 mm/year at monthly (August), seasonal (summer), and annual timescales, respectively. In contrast, decreasing PET trends are present only at the monthly and seasonal scales, with a maximum of, respectively, −1.82 (July) and −3.28 (summer) mm/year. Overall, the findings of this study are useful for climate change adaptation strategies to be pursued in the region. [ABSTRACT FROM AUTHOR]

In the management of border irrigation, infiltration function is important for improving irrigation efficiency. The main objective of this research was to evaluate the effect of soil water content management, irrigation water quality, and coefficients of the Kostiakov–Lewis infiltration equation on the output of the SIRMOD model (advance time, application efficiency, irrigation efficiency, Tail-water fraction, Deep percolation fraction, and cumulative infiltration). Treatments used consisted of three irrigation water qualities (EC = 0.6, 3 and 6 dS/m) and two soil water content managements (FC and 30% depletion of FC; FC is field capacity). Using a laboratory method, infiltrations were measured in soil columns for constant water head. Infiltration tests were applied on soil columns after first, fifth, and tenth irrigation events. For the simulation of border irrigation, the coefficients of 18 the modified Kostiakov–Lewis equation obtained from the columns were used. Simulating, two coefficients of the infiltration equation were kept constant, and the other coefficient was changed in the range of 0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75, and 2 times of the initial value. The result showed that soil sealing was observed only in the 30%FC management which significantly reduced infiltration. Sensitivity analysis showed that increasing the field length increased the parameters changes. Deep percolation fraction and application efficiency were the most affected by changes in infiltration coefficients and irrigation treatments. The output parameters under FC management had the most sensitive to variations in infiltration coefficients especially when the quality of water and soil was poor. Therefore, it is suggested that in the FC management, input parameters of the model are measured with higher precision and entered into the model. [ABSTRACT FROM AUTHOR]

[Objective] Qingtongxia irrigation district is one of the irrigation districts in northwestern China which rely on Yellow River water for irrigation. Using the water footprint concept, this paper proposes a system dynamic model to help improve agricultural water use efficiency in this district. [Method] Blue and green water footprints of major crops in the district were calculated from their evapotranspiration and transpiration. A system dynamics model for agricultural water use efficiency was then established, and the model was solved using the Vensim software. [Result] Irrigation water is the primary water source for agriculture in the district, forming a production water use pattern in which blue water is the main source and green water is a supplementary source. The blue and green water footprints vary oppositely in order to meet the demand of crops for water. On the premise to ensure constant blue water use for the crops, we selected the green water use coefficient and irrigation water use coefficient as parameters in the modelling. The model results show that increasing green water utilization coefficient from 0.7 to 0.8 can increase wheat production by 2.7x105 t, rice production by 2x105 t, and corn production by 5.5x105 t. We also found that increasing the irrigation water utilization efficiency by 10 can increase wheat production by 4.7x105 t, rice production by 3.5x105 t, and corn production by 7.7x105 t. Collectively, increasing green water utilization coefficient and irrigation water utilization coefficient simultaneously can increase wheat production by 7.5x105 t, rice production by 5.5x105 t, and maize production by 1.32x107 t. [Conclusion] Agricultural production in Qingtongxia irrigation area should consider increasing utilization of green water and improving agricultural water use efficiency by improving engineering and non-engineering facilities to increase crop yields. [ABSTRACT FROM AUTHOR]

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Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water is one of the most determining factors in obtaining high yields in oil palm crops. However, water scarcity is becoming a challenge for agricultural sustainability. Therefore, when the environmental supply of water is low, it is necessary to provide it to crops with the highest degree of efficiency. However, although irrigation technologies are available, for various reasons farmers continue to use inefficient irrigation systems, which causes resource losses. The objective of this study was to analyze the percentage of adoption of irrigation technologies for water management in oil palm crops and to classify the factors influencing their adoption by producers. The method for the classification of influential factors was based on multiple correspondence analysis and perceptron neural networks. The results showed that fewer than 15% of the producers adopt irrigation technologies, and the factors classified as influential in the adoption decision were the age of the palm growers, the size of the plantation, and the access to extension services. These results are the basis for the formulation of effective and focused extension strategies according to the characteristics of the producers and the local and technological specificity. [ABSTRACT FROM AUTHOR]

Multi-Attribute Decision-Making (MADM) is still an open issue under uncertain circumstances. This research aimed to introduce a new MADM method for dealing with highly uncertain circumstances. Lake Urmia in Iran suffers from natural and human stimuli. For rapid and sustainable lake rehabilitation, a multidisciplinary and flexible approach is needed to address the divergent benefits and multiple goals. MADM can be accomplished using various techniques such as the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), the Analytic Hierarchy Process (AHP), and others. According to the uncertainty, in recent years the hybrid of fuzzy logic with well-known MADM methods such as fuzzy AHP (FAHP) has been used frequently. The main problem of the traditional MADM methods (and fuzzy-based MADM methods) is their weakness in dealing with the ambiguous situations common in real-life scenarios, especially in water crisis problems. For example, the decision, which was accepted based on low-reliability data, tends to be useless or harmful. In contrast to the traditional MADM methods, which ignore the reliability of the information, Z-numbers, as a new generation of the fuzzy logic method, include both constraint and reliability of information and have great potential to explain human knowledge uncertainty. This study developed a new MADM approach based on the Z-numbers concept. In this regard, seven alternatives were proposed and evaluated using the economic, social, environmental, and technical criteria of sustainable development. The obtained results were then compared with the results of the AHP, FAHP, and TOPSIS methods. Improving irrigation efficiency was chosen as the best alternative based on the final ranking of the alternatives. [ABSTRACT FROM AUTHOR]

The nations that comprise the Gulf Cooperation Council (GCC) are located in one of the most water-stressed regions in the world. This region has faced serious socioeconomic and environmental development issues as a result of its increasing water demand over time. The extreme aridity, high rates of evaporation, and scarcity of nonrenewable groundwater resources in the GCC countries pose a significant threat to food security. This study aims to explore the impact of climate change on the potential availability of irrigation water in the State of Kuwait, which serves as an example of all GCC nations. A modeling scheme using CropWat8 was developed to study the impact of four climate change scenarios (encompassing the past, present, and future) on the net and gross irrigation water requirements (NIWR and GIWR) for selected agricultural crops, while also determining optimum irrigation schedules. Scenario 1 represented past climate conditions (1996–2006), while Scenario 2 represented the current situation (2007–2021). Projected scenarios (3 and 4) were analyzed using Representative Concentration Pathways (RCP) 4.5 and RCP 8.5, which were adopted by the IPCC to project the concentrations of greenhouse gases (GHG) emissions for 2060. The simulation results showed that compared with the current GHG levels, the increase in GHG emissions also increased the demand for NIWR by a minimum of 8.2% and a maximum of 15% for the same agricultural areas and cropping patterns. The measured GIWR in the field was 1915 m3, while the simulated NIWR was 1724 m3. With a drip irrigation efficiency of 90%, the model adequately demonstrated the validity of the CropWat8 package for simulating the climate impact on crop water requirements with a precision of approximately 92.2%. These findings suggest that the GCC countries should develop strategies to minimize GHG emissions and adopt innovative solutions for better management of water resources. [ABSTRACT FROM AUTHOR]

Nowadays, the leading role of data from sensors to monitor crop irrigation practices is indisputable. The combination of ground and space monitoring data and agrohydrological modeling made it possible to evaluate the effectiveness of crop irrigation. This paper presents some additions to recently published results of field study at the territory of the Privolzhskaya irrigation system located on the left bank of the Volga in the Russian Federation, during the growing season of 2012. Data were obtained for 19 crops of irrigated alfalfa during the second year of their growing period. Irrigation water applications to these crops was carried out by the center pivot sprinklers. The actual crop evapotranspiration and its components being derived with the SEBAL model from MODIS satellite images data. As a result, a time series of daily values of evapotranspiration and transpiration were obtained for the area occupied by each of these crops. To assess the effectiveness of irrigation of alfalfa crops, six indicators were used based on the use of data on yield, irrigation depth, actual evapotranspiration, transpiration and basal evaporation deficit. The series of indicators estimating irrigation effectiveness were analyzed and ranked. The obtained rank values were used to analyze the similarity and non-similarity of indicators of irrigation effectiveness of alfalfa crops. As a result of this analysis, the opportunity to assess irrigation effectiveness with the help of data from ground and space-based sensors was proved. [ABSTRACT FROM AUTHOR]

Restriction of water resources requires optimal use of agricultural water resources. In this regard, the use of new technology may increase irrigation efficiency. In arid and extremely arid regions such as Iran, the time and duration of irrigation is the key to achieving sustainable irrigation. Therefore, in this research, after constructing a garden in Iran, Karaj, Imam Khomeini Higher Education Center with an area of 0.05 ha, and installing equipment related to irrigation and fertilization, a fuzzy control system was designed to optimize water consumption and inputs, intelligent irrigation and fertilization system. The present study presents a practical solution based on artificial intelligence in which all stages of design and implementation are described. In this system, a microcontroller was first used to process and store data on soil moisture, ambient temperature and solar radiation. The fuzzy logic controller then takes these three inputs and based on the table of rules created for a specific product, produces the desired irrigation time and duration. Experimental results showed that, the developed system accurately compensates for the amount of water lost through evapotranspiration. It seems that the use of fuzzy control has a great impact on irrigation management and planning in the near future. [ABSTRACT FROM AUTHOR]

Water-saving irrigation area has increased steadily in China, with the rapid development of mechanized farming and land transfer. Among them, drip irrigation can greatly contribute to agricultural water-saving and high efficiency in northwest and northeast China. Drip irrigation can directly transport the fertilizer with water to the root zone of crops, and then effectively improve the fertilizer utilization rate. But the improper fertilization can lead to emitter blockage and a decrease in fertilization uniformity, resulting in crop yield loss. It is a high demand to implement chemical blockage in the field, due to the high requirements. In this study, the clogging performance was tested using commonly-used emitters (Inlaid cylindrical labyrinth emitter, E1; Inlaid patch labyrinth emitter, E2; Flanking labyrinth emitter, E3) with the Urea (UREA), Sulphate of potassium (SOP), Muriate of potash (MOP), Monoammonium phosphate (MAP), Diammonium phosphate (DAP) under different concentrations (0, 0.4, 0.8, 1.0, 1.2 g/L). The morphology and composition of clogged substances inside the emitter were analyzed to combine with field emission scanning electron microscopy (FESEM), surface energy spectrum analysis (EDS), and X-ray diffractometer (XRD). The sensitive fertilizer and emitter were then determined for the reasonable suggestions of fertigation. A theoretical basis was provided to inhibit the chemical clogging by an indoor simulated irrigation acceleration experiment. The results showed that there were different effects of fertilizers on the hydraulic properties and clog development of drip irrigation tape. There was no influence of potassium fertilizer on the hydraulic properties of E1 and E2, but little effect was found on the clogging degree of E3. Little influence was found in the mono-ammonium phosphate on the hydraulic performance of E1, but there was a slight blockage to E2 and E3. Diammonium phosphate was irrelated to the hydraulic performance of E1, but there was a slight blockage to E3, and a serious blockage to E2. Urea did not affect E1 and E2, but there was a clogging risk to E3. Therefore, the UREA and DAP were recommended to be avoided in irrigation. The uniformity increased with the increase of urea concentration in the range of 0.4-0.8 g/L, while the uniformity decreased in the range of 1.0-1.2 g/L. By contrast, the relative average discharge and irrigation uniformity of E3 decreased with the increase of irrigation times, whereas, the decrease rate increased with the increase of fertilizer concentration, as the diammonium phosphate concentration increased. Thus, the fertilization concentration of diammonium phosphate should not exceed 1.2 g/L. The local bulges on the surface of clogged substances were gradually higher than the initial state in the process of irrigation. The attached fouling was thinner, whereas, there was an increase in the scaly structures and the surface roughness. After irrigation, the attached fouling layer thickened, the surface roughness developed completely, and the structure was encrypted gradually from wide-scale structure to fine-scale structure. The dry weight of the clogged substance increased with the increase in the irrigation time. There was the consistency with the trend that the relative average discharge and uniformity of the emitter decreased with the increase in irrigation times. The more chemical fouling increased, the less the effect of water shear force on it, as the concentration of fertilizer solution increased. It is necessary to further improve the filtration efficiency of irrigation water, and reduce the content of suspended solids in irrigation water. A reasonable and perfect evaluation of water quality can also be conducted to reduce the occurrence of chemical blockage in fertigation systems. [ABSTRACT FROM AUTHOR]

Purpose. To develop a complex system for technical diagnostics of soil hydrotechnical structures of irrigation systems for operative identification of damaged sites, reduction of nonproduction water losses, and maintaining ecological and economic efficiency of the hydroeconomic national complex in the context of water and food security. Methodology. The result of the represented scientific study is reached by complex application of geophysical methods of the Earth’s natural pulse electromagnetic field (NPEMFE) and vertical electrical sounding (VES). That allows determining qualitative indices and parameters of the damaged sites of hydrotechnical structures and water filtration paths. Mathematical methods for determining quantitative parameters of filtration losses are applied. Analytical and technoeconomic comparison of some most widely used methods with the complex of techniques proposed in the study are performed. Findings. Field studies and analytical calculations helped determine that, depending on the design parameters of retention basins and modes of their operations, water losses are from 50 to 60 m3/month per 1 m of the structure length. In some cases total filtration losses per month can reach up to 100 m3 per 1 m of the length. As for the monetary equivalent, in terms of average water cost being 0.12 EUR/m3, water loss in one standard retention basin with the conventional dimensions of 100 × 100 m is EUR 2.5 thousand per month (EUR 12.5 thousand per season). Originality. The possibility of using a complex of geophysical methods for diagnosing technical conditions of soil dams of retention agricultural basins has been substantiated scientifically. The complex is of high informativity making it possible to determine rapidly the sites with increased filtration in the hydrotechnical objects. According to the comparison of the available models for evaluating possible filtration losses from the retention basins of irrigation systems, the parameters of estimate indicators, ensuring high reliability of the results, have been substantiated. Practical value. Point determination of the sites with filtration water losses makes it possible to focus the repair and renewal operations on the most damaged sites that reduce considerably the time and costs along with the increase in general efficiency of the irrigation system operation. [ABSTRACT FROM AUTHOR]

Background and Objectives: Smear layer forms during cleaning and shaping can obstruct the entry of both irrigant and sealant into the dentinal tubules, resulting in the accumulation of the bacteria and their byproducts. To ensure effective adhesion and better periapical healing, it is strongly advised to remove the smear layer before proceeding with root canal obturation. This study was designed to compare the efficiency of laser-activated irrigation (LAI) in removing the smear layer and debriding the most apical third of the root canal. Materials and Methods: Sixty-five extracted human teeth with straight single roots were randomly and equally divided into four laser and one control groups. Root canals in all samples were shaped using prime size TruNatomy rotary files. During preparation, each canal was irrigated with 3 mL of 3% NaOCl and 3 mL of 17% EDTA alternately, followed by the irrigation with 10 mL of distilled water to avoid the prolonged effect of EDTA and NaOCl solutions. Final irrigation of 5 mL of 17% EDTA of the root canal was done to eliminate the smear layer and was subsequently activated by an endodontic ultrasonic tip for 20 s three times (control group), a flat-end laser tip (test groups 1 and 3) or a taper-end laser tip (test groups 2 and 4) for two cycles. The time of each cycle activation was 10 s (groups 1 and 2) or 20 s (groups 3 and 4) in which the Er:YAG laser of 2940 nm was used. The laser operating parameters were 15 Hz and 50 μs pulse duration. The samples were then split longitudinally and subjected to scanning electron microscopy (SEM). Results: The remaining smear layer at the apical part of the root canals was statistically significant between the control group and the laser groups 1 (p = 0.040) and 2 (p = 0.000). Within the laser groups, the exposed tubules count was greater in the laser with the flat tip as compared with the tapered tip (Laser 1 > Laser 2 and Laser 3 > Laser 4). Finally, no significant differences in the count of debris between the laser groups and control group were observed, except for laser 4 (p < 0.05), which had the highest count of debris. Conclusion: LAI to remove debris and smear layer at the apical third of the root canal is inferior to the current ultrasonic technique. However, when using the Er:YAG LAI, it is recommended to use a flat tip design for 10 s for two cycles to ensure maximum debridement of the apical dentin surface. [ABSTRACT FROM AUTHOR]

Agricultural irrigation practices have changed through time as technology has enabled more efficient conveyance and application. In some agricultural regions, irrigation can contribute to incidental aquifer recharge important for groundwater return flows to streams. The Henrys Fork Snake River, Idaho (United States) overlies a portion of the Eastern Snake Plain Aquifer, where irrigated agriculture has occurred for over a century. Using irrigator interviews, aerial and satellite imagery, and statistical streamflow analysis, we document the impact of farm-scale decisions on basin-scale hydrology. Motivated to improve economic efficiency, irrigators began converting from surface to center-pivot sprinkler irrigation in the 1950s, with rapid adoption of center-pivot sprinklers through 2000. Between 1978–2000 and 2001–2022, annual surface-water diversion decreased by 311 Mm3 (23%) and annual return flow to the river decreased by 299 Mm3 over the same period. Some reaches that gained water during 1978–2000 lost water to the aquifer during the later period. We use an interdisciplinary approach to demonstrate how individual farm-scale improvements in irrigation efficiency can cumulatively affect hydrology at the landscape scale and alter groundwater-surface water relationships. Return flows are an important part of basin hydrology in irrigated landscapes and we discuss how managed and incidental aquifer recharge can be implemented to recover return flows to rivers.

Abstract A recent study by Ambika and Mishra (2022, https://doi.org/10.1029/2021EF002642) asserted using simulated evidence that a shift towards drip irrigation from channel irrigation in the Indo‐Gangetic Plains will result in alleviation of moist heat stress and water savings. The assumptions, parameterizations, and approach adopted in this study do not adequately represent fundamentals of irrigation science, management, and engineering, as well as realities of local agricultural water management in the Indo‐Gangetic Plains. This comment attempts to highlight these inadequacies of the paper and related literature, by focusing on four major aspects related to irrigation process, local land‐use, timing of irrigation and moist heat stress, and water accounting. These weaknesses in irrigation processes modeling result in overlooking of indispensable aspects that should be accounted for to comprehensively assess impacts of irrigation method choice on regional weather and water resources.

Accurate estimation of actual evapotranspiration () is a critical component in improving agricultural water management and water use efficiency. Remote sensing (RS) techniques provide a promising inexpensive tool for reliable crop water consumption estimations compared to conventional field measurements. Having agricultural land fragmentation and mixed cropping systems in the Nile River Delta, traditional methods of estimating are seemingly challenging. The present study aims to improve agricultural water management at the meso scale using RS-based techniques. Four RS-based methods were employed to estimate in mixed cropping farms at the Nile River Delta. The adopted methods include: (i) the Surface Energy Balance Algorithm for Land (SEBAL), (ii) the Simplified Surface Energy Balance algorithm (SSEB), (iii) Earth Engine Evapotranspiration Flux (EEFLUX) product, and (iv) the crop coefficient () method. The analysis of variance (ANOVA) test showed a significant difference between the employed RS-based techniques. During the winter season 2018–2019, the estimated varied from 331.33 mm/season to 389.34 mm/season, with an average of 358.76 mm/season. The irrigation efficiency was estimated to be about 55–63%, with an average of 59.55%. The study developed an algorithm to schedule the operation hours of irrigation pumps in the study area based on actual water requirements and pump capacity. The study highlights the relevance of RS methods and the importance of the equitable distribution of water in small farms to enhance water management. HIGHLIGHTS A remote sensing-based approach is developed to estimate actual crop evapotranspiration in arid regions.; The developed approach is tested on small scale farms with mixed vegetation in the Nile Delta.; Irrigation efficiency and irrigation schedule are determined based on estimated actual evapotranspiration.; Remote sensing-based methods can be adopted to enhance irrigation water management in small farms.;