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In this article, the authors developed a novel method for the moisture mapping of the soil surface of agrophytocenosis using a neural network based on synchronized radar and multispectral optoelectronic data from Sentinel-1,2. The significance of this research lies in its potential to enhance precision farming practices, which are increasingly vital in addressing global agricultural challenges such as water scarcity and the need for sustainable resource management. To verify the developed method, data from two experimental plots were utilized. These plots were located on irrigated soybean crops, with the first plot situated on the right bank (plot No. 1) and the second on the left bank (plot No. 2) of the lower Volga River. Two experimental soil moisture geodatasets were created through measurements and geo-referencing points using the gravimetric method (for plot No. 1) and the proximal sensing method (for plot No. 2) employing the Soil Moisture Sensor ML3-KIT (THETAKIT, Delta). The soil moisture retrieval algorithm was based on the use of a neural network to predict the reflection coefficient of an electro-magnetic wave from the soil surface, followed by inversion into soil moisture using a dielectric model that takes into account the soil texture. The input parameter of the neural network was the ratio of the microwave radar vegetation index (calculated based on Sentinel-1 data) to the index (calculated based on the data of multispectral optoelectronic channels 8 and 11 of Sentinel-2). The retrieved soil moisture values were compared with in situ measurements, showing a determination coefficient of 0.44–0.65 and a standard deviation of 2.4–4.2% for plot No. 1 and similar metrics for plot No. 2. The conducted research laid the groundwork for developing a new technology for remote sensing of soil moisture content in agrophytocenosis, serving as a crucial component of precision farming systems and agroecology. The integration of this technology promotes sustainable agricultural practices by minimizing water consumption while maximizing crop productivity. This aligns with broader environmental goals of conserving natural resources and reducing agricultural runoff. On a larger scale, data derived from such studies can inform policy decisions related to water resource management, guiding regulations that promote efficient water use in agriculture. [ABSTRACT FROM AUTHOR]

Water sustainability involves several natural and human spheres conditioning the availability and quality of water resources and life conservation. Regarding water quality, currently emerging pollutants (EPs) are a key topic at global scale since they are difficult to remove by traditional water treatment systems. In this context, this work aims to evaluate experts’ perception of several EPs issues with a special focus on semi-arid Mediterranean areas where EPs are negatively impacting water, environmental, and agricultural systems as, in these areas, effluents from water treatment plants are widely reused in the irrigation of crops, urban gardens, and golf courses or directly discharged on natural streams. Particularly, a detailed survey composed of questions about EPs regulation, risk insight, equipment, social and economic impacts, was performed collecting 437 responses. Main results suggested that EPs existence may pose a significant risk and a destabilizing factor in wastewater reuse, with negative impacts to crop irrigation, being managers the class with more concern followed by scientifics and administratives. New EPs regulations raises uncertainty amongst experts since 29 % considered positive its creation, while 20 % estimated this fact as regular and 14 % as negative. As well, although the combination of technologies to improve EPs removal generated agreement, aspects like the treatment charges at water treatment plants or the price/bill of EPs-free water were features of ambiguity. Within EPs elimination, the three expert groups highlighted that technologies impacts in the sustainability spheres will be positive on public health (87 % of responses), social trust (75 %), and environmental sustainability (76 %). Likewise, 88 % of experts concurred that the future of wastewater reuse relies on a combination of technologies. These findings offer valuable information to water legislators and policymakers to manage water resources, especially in semi-arid areas due to the final use of treated effluents and, therefore, the great implications for agriculture, environment and human health.

Abstract Freshwater shortages in the Middle East and North Africa's region (MENA) cause serious issues, while climate change causes even more issues. The current study examines how climate change may impact future irrigation requirements in Egypt's Upper Region using the medium greenhouse emission RCP 4.5 and high emission RCP 8.5 scenarios. Based on the Intergovernmental Panel on Climate Change (IPCC) and the Fifth Assessment Report, the climatic projections for RCPs 4.5 and 8.5 for the years 2023–2080 and 2081–2100 were used to determine the patterns of temperature and rainfall in the upper Egypt territory. The CROPWAT model was employed to estimate reference evapotranspiration (ETo) and net irrigation water requirement (NIWR) for the upper Egypt territory key crops sugar cane, potatoes, berseem clover (alfalfa), dry bean, wheat, cotton, maize, and tomato based on the predicted meteorological conditions. Five different scenarios for the key crops' future irrigation needs were calculated. The results reveal that under RCP 4.5 greenhouse emission for the periods 2023–2080 and 2081–2100, respectively, the overall NIWR for all examined crops increases by 5.1 and 5.9% in comparison to the current (2022) total NIWR for all crops. The total NIWR for all crops analyzed increases by 7.7 and 9.7% under the RCP 8.5 greenhouse emission scenario for the periods 2023–2080 and 2081–2100, respectively, in contrast to the current total NIWR for all crops. It is important to consider changes in water resource management in the MENA region, such as applying modern irrigation systems, using crop pattern rotation strategies with minimal water demands, and changing crop calendars or the times and locations of cropping activities.

Due to the scarcity of fresh water for crop irrigation in semi-arid areas, sustainable use of treated municipal wastewater is essential. Chlorine for wastewater disinfection added in wastewater treatment plants may be toxic for crops and can degrade cultivated soils. This study evaluates the crop and soil response to irrigation with treated municipal wastewater (with or without chlorination) in comparison to clear water. Small plants of tomato and cabbage and young bergamot trees were irrigated in pots throughout two months. The use of chlorinated or non-chlorinated wastewater did not significantly change biomass growth, morphological parameters and the efficiency of energy transfer. Significant reductions (40–50%) in the stem diameter of tomato and bergamot plants and differences (−25% to 53%) in all physiological parameters were measured for tomato immediately after the irrigation start. A decrease (−55%) in stomatal conductance and transpiration rate together with an increase (+80%) in water use efficiency were also recorded in bergamot after 30 days of irrigation. This type of irrigation water did not induce significant changes in soil properties, except for a decrease in pH (−20%) in bergamot soils after the irrigation start and in electric conductivity (EC, −40%) at the end of the irrigation period for all species. Irrigation of plants with chlorinated wastewater increased the weight of the fresh biomass (+56%) of leaves and the stem diameter (−60%) of tomato and decreased water use efficiency (+67%) in bergamot after the irrigation start. After two months, decreases in stomatal conductance and transpiration rate in cabbage (over 50%) and increases in water use efficiency in cabbage and bergamot (by 40% and 70%, respectively) were evident. Among the studied soil properties, land application of chlorinated wastewater only reduced electrical conductivity (−47%). Overall, this study demonstrated that the use of treated municipal wastewater (with or without chlorination) does not have detrimental impacts on both plant growth (at least for tomato, cabbage and bergamot) and soil health in the short term. [ABSTRACT FROM AUTHOR]

Freshwater shortages in the Middle East and North Africa's region (MENA) cause serious issues, while climate change causes even more issues. The current study examines how climate change may impact future irrigation requirements in Egypt's Upper Region using the medium greenhouse emission RCP 4.5 and high emission RCP 8.5 scenarios. Based on the Intergovernmental Panel on Climate Change (IPCC) and the Fifth Assessment Report, the climatic projections for RCPs 4.5 and 8.5 for the years 2023–2080 and 2081–2100 were used to determine the patterns of temperature and rainfall in the upper Egypt territory. The CROPWAT model was employed to estimate reference evapotranspiration (ETo) and net irrigation water requirement (NIWR) for the upper Egypt territory key crops sugar cane, potatoes, berseem clover (alfalfa), dry bean, wheat, cotton, maize, and tomato based on the predicted meteorological conditions. Five different scenarios for the key crops' future irrigation needs were calculated. The results reveal that under RCP 4.5 greenhouse emission for the periods 2023–2080 and 2081–2100, respectively, the overall NIWR for all examined crops increases by 5.1 and 5.9% in comparison to the current (2022) total NIWR for all crops. The total NIWR for all crops analyzed increases by 7.7 and 9.7% under the RCP 8.5 greenhouse emission scenario for the periods 2023–2080 and 2081–2100, respectively, in contrast to the current total NIWR for all crops. It is important to consider changes in water resource management in the MENA region, such as applying modern irrigation systems, using crop pattern rotation strategies with minimal water demands, and changing crop calendars or the times and locations of cropping activities. [ABSTRACT FROM AUTHOR]

This work is a case study whose objective is prediction of irrigation needs of corn crops in different regions of Ecuador; being this a fundamental basic food for the country's economy, as in the remaining countries of the Andean area. The proposed methodology seeks to help improving the quality of corn crop. Specifically, we propose the application of regression models, within the framework of Functional Data Analysis (FDA), to predict the amount of rainfall (scalar response variable) in the places with the highest production of corn in Ecuador, as a function of functional covariates such as temperature and wind speed. From the estimation of the amount of rainfall, effective precipitation is calculated. This is the fraction of water used by the crops, from which the value of real evapotranspiration or ETc is obtained and, more importantly, the irrigation requirements at each stage of the corn crop, for its adequate physiological development. Application of regression models based on functional basis, Functional Principal Components (FPC) or Functional Partial Least Squares (FPLS) for scalar response variable, allows us to use the information of variables such as wind speed and temperature (of functional nature) in a better way than using multivariate models, for predicting the amount of rainfall, obtaining, as a result, very explicative models, defined by a high goodness of fit (R2=0.97, with 6 significant parameters and an error of 0.14) and practical utility. The model has been also applied to North Peru regions, obtaining rainfall prediction errors between 9% and 22%. Thus, the geographical limitations of the model could be the Andean regions with similar climate. In addition, this study proposes the application of FDA exploratory analysis and FDA outlier detection techniques as a common and useful practice in the specific domain of rainfall prediction studies, prior to applying the regression models.

Drought Agricultural is the most repeatedly natural disaster, particularly in arid/semi-arid regions. It causes diversity losses such as crop quality, production, utility rate, and food security as the most important threat. In this study, first, SPEI index is calculated whereby precipitation and temperature data, respectively. The correlation analysis performed between crop yield anomalies and SPEI index to determine critical month/months in which drought severity is severe, and crop reproductive stage is vulnerable. After this step, the best timescale of SPEI is demonstrated and the slope between the best SPEI and crop yield anomalies is calculated to compute ADSI values. Finally, for appreciation of irrigation effects in response to drought stress, analysis of covariance and panel data regression due to SPEI values and crop yield are applied. In addition, the relationship between the SPEI, VHI, and ADSI will be discussed. It is necessary to state that the majority of crops in the region of interest are studied. Also, for obtaining VHI, LST, and NDVI indices as MODIS products have been utilized in the study area. For the most crops, The results indicated that July was a critical month and for the residual crops, August was a critical month with severe drought, whereas some crops had three critical months. Furthermore, significant amount of the crops have been damaged in the flowering stage, plus the corn was more sensitive to drought relative to other crops. The results derived from panel data model regression show that drought sensitivity is incremental in non-irrigation harvest and vice versa. In other words, non-irrigated crops are more sensitive to drought and drought stress increase in an arid and semi-arid acres, significantly. At the end, comparing results of VHI and ADSI imply their strong relationship. ADSI and VHI were able to quantitatively measure the drought intensity. Also, the panel data regression was able to discriminate irrigation and non-irrigation effects. [ABSTRACT FROM AUTHOR]

The increase in irrigated crop areas, especially in countries such as Spain and Italy, has led to an increase in technological solutions for monitoring the irrigation. Furthermore, the centre pivot irrigation systems used in these crops have facilitated the daily work of farmers in recent years, however, the monitoring of these systems and the reporting of problems in their operation has become a key aspect during the growing season. For this reason, different monitoring solutions have been proposed from the area of Precision Agriculture and Information and Communication Technologies (ICTs). Nevertheless, it is necessary that these solutions take into account the digital divide their potential users may suffer and be low-cost solutions in order to be attractive to the end-users. This paper presents several low-cost solutions using novel user interfaces and wireless communication technologies for the monitoring of this type of irrigation systems. This paper presents the results obtained after the deployment of the proposed systems on a real environment and the main conclusions drawn after their use in irrigated maize crops. • LoRaWAN and GPS allow affordable monitoring systems for centre pivot irrigation. • Chatbots and voice assistants help to avoid the digital divide. • Edge Computing Devices and LPWANs enable new AMR solutions for water meters. [ABSTRACT FROM AUTHOR]

In semi-arid regions that are characterized by large agricultural activities, a high volume of water is needed to cover the water requirements for agricultural production. Due to low precipitation and the associated limited availability of surface water, aquifers often represent the main source of irrigation water in these regions. Especially in coastal aquifers, high groundwater abstraction rates may change the flow dynamics of the aquifer and may lead to saltwater intrusion. In this study, within the framework of German-Moroccan international cooperation, the agricultural areas for the summer period 2019 of the Chtouka coastal aquifer in southern Morocco are classified using optical and multi-spectral Sentinel 2 data. Based on the developed land use maps, the groundwater abstraction for irrigation is then quantified by referring to local farmers' irrigation practices. Following this approach, the total amount of groundwater abstraction is estimated at 157 million m3 for the summer period 2019 in the Chtouka aquifer. [ABSTRACT FROM AUTHOR]

We consider a simple crop irrigation model and study the optimal control which consists of maximizing the biomass production at harvesting time. A specificity of this work is to impose a quota on the water used for irrigation, in a context of limited resources. The model is written as a 2d non‐autonomous dynamical system with a state constraint, and a non‐smooth right member given by threshold‐based soil and crop water stress functions. We show that when the water quota is below the threshold giving the largest possible production, the optimal strategy consists of irrigating once. We then show that the optimal solution can have one or several singular arcs, and therefore be better than simple bang‐bang controls, as commonly used. The gains over the best bang‐bang controls are illustrated on numerical simulations. These new feedback controls that we obtain are a promising first step towards the concrete application of control theory to the problem of optimal irrigation scheduling under water scarcity. [ABSTRACT FROM AUTHOR]

Hydroponic crops is a special type of crop because it tries to reduce space and water use for certain plants. Normally, the estimation of the water of the crops in underdeveloped countries is made in a manual way generating waste of water. In the water estimation, ideal factors can be considered in which the crops carry out their biological process with a high yield. The hydric estimation can be measured as a function of the soil, the ambient temperature, the diameters of the roots, and the interspace between the plants. We consider carrying out the water estimation checking each plant to reach the correct progress of plants in the crop. We show an approach to integrating hardware and software components. The prototype is capable of calculating the evapotranspiration of crops and making a water estimation according to the several factors in each plant and the measured data from electronic sensors in order to reduce water in each irrigation. Additionally, the system allows the farmers to schedule the irrigation.

Scientific organizations and researchers are eager to apply recent technological advancements, such as sensors and actuators, in different application areas, including environmental monitoring, creation of intelligent buildings, and precision agriculture. Technology-assisted irrigation for agriculture is a major research innovation which eases the work of farmers and prevents water wastage. Wireless sensor networks (WSNs) are used as sensor nodes that directly interact with the physical environment and provide real-time data that are useful in identifying regions in need, particularly in agricultural fields. This paper presents an efficient methodology that employs WSN as a data collection tool and a decision support system (DSS). The proposed DSS can assist farmers in their manual irrigation procedures or automate irrigation activities. Water-deficient sites in both scenarios are identified by using soil moisture and environmental data sensors. However, the proposed system's accuracy is directly proportional to the accuracy of dynamic data generated by the deployed WSN. A simplified outlier-detection algorithm is thus presented and integrated with the proposed DSS to fine-tune the collected data prior to processing. The complexity of the algorithm is O(1) for dynamic datasets generated by sensor nodes and O(n) for static datasets. Different issues in technology-assisted irrigation management and their solutions are also addressed.

In semi-arid regions that are characterized by large agricultural activities, a high volume of water is needed to cover the water requirements for agricultural production. Due to low precipitation and the associated limited availability of surface water, aquifers often represent the main source of irrigation water in these regions. Especially in coastal aquifers, high groundwater abstraction rates may change the flow dynamics of the aquifer and may lead to saltwater intrusion. In this study, within the framework of German–Moroccan international cooperation, the agricultural areas for the summer period 2019 of the Chtouka coastal aquifer in southern Morocco are classified using optical and multi-spectral Sentinel 2 data. Based on the developed land use maps, the groundwater abstraction for irrigation is then quantified by referring to local farmers’ irrigation practices. Following this approach, the total amount of groundwater abstraction is estimated at 157 million m3 for the summer period 2019 in the Chtouka aquifer.

The discharging temperature of large reservoirs with high water head has great influence to the agricultural irrigation and river water ecological environment. Analyzing the vertical distribution law of water temperature and the influence of stratified water intake to the discharging temperature can provide scientific basis for the design and regulation of reservoirs. Taking Qianping Reservoir as a research object, the water temperature calculation model was set up by the DELFT3D FLOW software. The model was used to analyze the discharged water temperature of the high-head and large reservoir in two different ways, stratified water intake and single layer water intake. The calculation model selected the ocean temperature model and collected the mean multi-year data of the surrounding weather stations as the background data. Hydrological data from four typical years in the Qianping Reservoir, ie, high flow year, normal flow year, low flow year, and especially low flow year were used as initial conditions. The upstream water inflow and downstream water intake were selected as boundary conditions. The analysis results show that the temperature of discharged water and natural water are close when adopting the stratified water intake solution, which can meet the needs of crop irrigation. [ABSTRACT FROM AUTHOR]

Abstract Wastewater is an important resource in water-scarce regions of the world, and its use in agriculture requires the guarantee of acceptable public health risks. The use of fecal indicator bacteria to evaluate safety does not represent viruses, the main potential health hazards. Viral pathogens could complement the use of fecal indicator bacteria in the evaluation of water quality. In this study, we characterized the concentration and removal of human adenovirus (HAdV) and norovirus genogroup II (NoV GII), highly abundant and important viral pathogens found in wastewater, in two wastewater treatment plants (WWTPs) that use different tertiary treatments (constructed wetland vs conventional UV, chlorination and Actiflo® treatments) for a year in Catalonia. The main objective of this study was to develop a Quantitative Microbial Risk Assessment for viral gastroenteritis caused by norovirus GII and adenovirus, associated with the ingestion of lettuce irrigated with tertiary effluents from these WWTPs. The results show that the disease burden of NoV GII and HAdV for the consumption of lettuce irrigated with tertiary effluent from either WWTP was higher than the WHO recommendation of 10−6 DALYs for both viruses. The WWTP with constructed wetland showed a higher viral reduction on average (3.9 and 2.8 logs for NoV GII and HAdV, respectively) than conventional treatment (1.9 and 2.5 logs) but a higher variability than the conventional WWTP. Sensitivity analysis demonstrated that the input parameters used to estimate the viral reduction by treatment and viral concentrations accounted for much of the model output variability. The estimated reductions required to reach the WHO recommended levels in tertiary effluent are influenced by the characteristics of the treatments developed in the WWTPs, and additional average reductions are necessary (in WWTP with a constructed wetland: A total of 6.7 and 5.1 logs for NoV GII and HAdV, respectively; and in the more conventional treatment: 7 and 5.6 logs). This recommendation would be achieved with an average quantification of 0.5 genome copies per 100 mL in reclaimed water for both viruses. The results suggest that the analyzed reclaimed water would require additional treatments to achieve acceptable risk in the irrigation of vegetables with reclaimed water. Graphical abstract Image 1 Highlights • Quantitative microbial risk assessment of norovirus and adenovirus. • Health risk associated with the ingestion of lettuce irrigated with reclaimed water. • Constructed wetland vs conventional UV, chlorination and Actiflo® treatments. • Reductions required to reach the WHO recommended levels in tertiary effluent. [ABSTRACT FROM AUTHOR]

A combination of a changing global climate coupled with rapid socio-economic development is putting unprecedented pressure on water, energy, and food resources. Addressing these issues within a nexus approach can help to identify appropriate management practices and strategic policies to ensure natural resources are used more sustainably thus avoiding exacerbating issues of water scarcity and food insecurity. In this study, we used an integrated water resource planning and irrigation model (WEAP) to assess emerging water-energy nexus issues on the Santa Elena peninsula in Ecuador. Simulated water demands showed that current water resources availability is insufficient to meet full irrigation requirements, especially during the dry season. Annual average energy demand for water conveyance in the SEP was significantly higher than for irrigation with 94.5 GWh and 13.5 GWh being used, respectively. Future challenges associated with changes in agricultural irrigation and urban demands within the SEP were evaluated using scenario analysis. This included considering various scenarios such as agricultural expansion, climate change, population growth, and a shift to export-oriented agriculture. The study underscores the significance of nexus thinking in guiding policy and decision-making in Santa Elena, although the limited data prevents its use in an operational framework. The benefits of adopting an integrated modelling approach to analyse water and energy nexus trade-offs are also discussed. [Display omitted] • An integrated reservoir simulation modelling approach for nexus analysis is used. • Water-energy nexus trade-offs during baseline and future scenarios are considered. • The system is unable to meet irrigation demand under baseline and all scenarios. • Energy demand for conveyance system is seven times higher than for irrigation. • Infrastructure expansion and more efficient agriculture needed if scenarios realise. [ABSTRACT FROM AUTHOR]

The distribution of metals in cyanobloom-forming lakes, and potential risks of these metals during irrigation with water derived from the bloom were evaluated in this study. Seven metals were monitored throughout a cyanobacterial bloom season in Lake Taihu. Cyanobloom bio-dilution of the targeted metals could be explained by the negative relationships between total phytoplankton metal contents (Cu, Fe, Zn, Pb and Cr) and Chl a concentrations ( p < 0.05). Meanwhile, the ratios of extracellular bound to total cellular bound metals (Cu, Zn, Pb, Cr and Cd) were positively correlated with the ratios of cyanophyta to total phytoplankton ( p < 0.01), indicating the enhanced extracellular bound of these metals during cyanobloom period. Secondly, Cd, Pb and Cr were detected in several local vegetables. In comparison to reference vegetables, vegetables ( e.g. , radish, soybean, and cowpea), which were irrigated with cyanobloom broth collected from Lake Taihu, presented high health risk index (HRI) and were not safe for human consumption. Collectively, the frequent dominant colonial Microcystis blooms which performed high metal affinity might mediate the distribution of heavy metals in lake and potentially transferred these pollutants into terrestrial system. [ABSTRACT FROM AUTHOR]

Water use and the cost of water are key factors when considering the net value of urban agriculture (UA). This systematic review critically evaluates past and recent UA yield research from the perspective of water use efficiency. A systematic literature search was conducted using the databases Scopus, ProQuest Agriculture and Environment, and Web of Science for references from 1975 to 2018, with 25 articles meeting the inclusion criteria. Of these, only five articles had actively collected UA water use data, all on purpose-built experimental gardens. Considering the scarcity of UA water use efficiency and water measurement literature, South Australia is presented as a case study to demonstrate the considerable diversity of water pricing, water sources and irrigation methods available to urban food growers. The practical challenges of garden placement and the wide variety of cultivation techniques, water sources and irrigation methods are reviewed. Four equations to calculate the water use efficiency (WUE) of UA are proposed and demonstrated. Collection of additional UA water use data would support more robust evaluations of the water use efficiency and economic implications of different cultivation techniques. Further work in this field will enable a realistic understanding of the current and future contribution of UA to our society.

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Wastewater is a valuable resource for water-scarce regions, and is becoming increasingly important due to the rising frequency of droughts as a result of climate change. The health risks derived from ingestion of lettuce that has been irrigated with effluent from a wastewater treatment plant (WWTP) in Catalonia (Spain) were estimated following a quantitative microbial risk assessment (QMRA) approach using site-specific data. Norovirus (NoV) was selected for this analysis, since it is the most common cause of acute gastroenteritis outbreaks in Catalonia. Two scenarios, irrigation with secondary and with tertiary effluent, were analysed. An uncertainty analysis was conducted to determine the impact of possible internalization of NoV into edible parts of the lettuce. The mean disease burden for ingestion of lettuce irrigated with secondary and tertiary effluent was 7.8 × 10 − 4 Disability Adjusted Life Years (DALYs) per person per year (pppy) and 3.9 × 10 − 4 DALYs pppy, respectively. A sensitivity analysis revealed that the model parameters with higher influence on the probability of disease are the concentration of NoV in the effluent and the consumption of lettuce. In order to decrease the disease burden to the guidance level of 10 − 6 DALYs pppy, the tertiary treatment should be able to achieve a 4.3 log reduction of the concentration of NoV. If internalization of NoV into lettuces occurs, this would require a reduction of 7.6 log. This is the first time that site specific data and virus internalization in crops are incorporated in a QMRA of irrigation of lettuce and its impact is quantified. [ABSTRACT FROM AUTHOR]

Passive uptake of contaminants of emerging concern (CECs) and its relationship with physicochemical properties, such as lipophilicity (LogKow), ionization behavior (pKa), distribution coefficient (LogDow) and transpiration rate are scarcely studied. In the current study, hydroponically grown corn (Zea mays) was exposed to carbamazepine (CBZ), fluoxetine (FLX), gemfibrozil (GBZ), triclosan (TRI) and atrazine (ATZ)) at environmentally relevant concentrations (20 μg/L each one). Plant tissue concentrations of CECs were determined several times over 21 days. Eighteen plants were used, nine exposed to the CECs and nine untreated. Whole plants were harvested at 7, 14 and 21 days and separated into roots, stem, leaf and male bud flower (only at 21 days). Hydroponic solution was maintained at pH 5.5 throughout the study. CECs concentrations in the exposure solution and tissues were determined by LC-MS/MS. ATZ metabolites desisopropylatrazine (DIA) and desethylatrazine (DEA) were determined by LC-DAD. In shoot tissues, CBZ, FLX and ATZ were detected, while TRI and GBZ were detected only in roots. Root concentrations were related with LogKow (R2 ROOT = 0.415). Leaf and stem concentrations of CBZ, FLX and ATZ were linked with LogKow and strongly linked with pKa. Transpiration was related with CBZ and ATZ in shoot, but not related with FLX shoot levels. Neutral compounds such as CBZ (pKa = 13.94; 100% neutral) and ATZ (pKa = 1.6; 85% neutral) were taken up passively with transpiration. Root accumulation was related with CECs lipophilicity, while translocation and bioaccumulation in shoot were not only related with lipophilicity, but also with CECs ionization behavior and transpiration. [Display omitted] • Triclosan and gemfibrozil were accumulated mainly in roots. • Carbamazepine, fluoxetine and atrazine were translocated from roots to shoot. • Carbamazepine and atrazine uptake and translocation were explained by lipophilicity, ionization and transpiration. • Fluoxetine uptake and translocation were explained by the lipophilicity. • Atrazine was biodegraded to DIA in leaf and stem. [ABSTRACT FROM AUTHOR]

Raw hospital wastewater is a source of excessive heavy metals and pharmaceutical pollutants. In water-stressed countries such as Pakistan, the practice of unsafe reuse by local farmers for crop irrigation is of major concern. In our previous work, we developed a low-cost bacterial consortium wastewater treatment method. Here, in a two-part study, we first aimed to find what physico-chemical parameters were the most important for differentiating consortium-treated and untreated wastewater for its safe reuse. This was achieved using a Kruskal–Wallis test on a suite of physico-chemical measurements to find those parameters which were differentially abundant between consortium-treated and untreated wastewater. The differentially abundant parameters were then input to a Random Forest classifier. The classifier showed that 'turbidity' was the most influential parameter for predicting biotreatment. In the second part of our study, we wanted to know if the consortium-treated wastewater was safe for crop irrigation. We therefore carried out a plant growth experiment using a range of popular crop plants in Pakistan (Radish, Cauliflower, Hot pepper, Rice and Wheat), which were grown using irrigation from consortium-treated and untreated hospital wastewater at a range of dilutions (turbidity levels) and performed a phytotoxicity assessment. Our results showed an increasing trend in germination indices and a decreasing one in phytotoxicity indices in plants after irrigation with consortium-treated hospital wastewater (at each dilution/turbidity measure). The comparative study of growth between plants showed the following trend: Cauliflower > Radish > Wheat > Rice > Hot pepper. Cauliflower was the most adaptive plant (PI: −0.28, −0.13, −0.16, −0.06) for the treated hospital wastewater, while hot pepper was susceptible for reuse; hence, we conclude that bacterial consortium-treated hospital wastewater is safe for reuse for the irrigation of cauliflower, radish, wheat and rice. We further conclude that turbidity is the most influential parameter for predicting bio-treatment efficiency prior to water reuse. This method, therefore, could represent a low-cost, low-tech and safe means for farmers to grow crops in water stressed areas. [ABSTRACT FROM AUTHOR]

• NC-RUS technique enables plant water status assessment on citrus in the field. • Resonant frequency, velocity and Q-factor were evaluated as water stress indicators. • Signal intensity and sensitivity performance of Q-factor was similar to Ψ leaf at midday. • A strong linear correlation was found between Q-factor and Ψ leaf (R2=0.57). Non-Contact Resonant Ultrasound Spectroscopy (NC-RUS) has emerged as a powerful tool to determine plant water status in a non-destructive, non-invasive and rapid way. In this study, ultrasonic parameters directly obtained from experimental measurements in the field using NC-RUS - such as resonant frequency (f res), velocity (v) and Q-factor - were evaluated as potential water stress indicators in Citrus plants. The experiments were carried out in two-year-old mandarin trees (Citrus clementina Hort. ex Tan. 'Clemenules') grown in pots in an open greenhouse where two different groups of plants were tested: a Control group (full irrigation) and a Drought Stress group (DS) whose irrigation was withdrawn during 7 days, followed by a 16 days recovery period. Soil water content, leaf water potential (Ψ leaf) and the considered ultrasonic parameters were measured in the same leaves. f res detected changes between control and DS at day 7 without irrigation. Conversely, v showed differences after day 3, which were statistically significant at day 7, enabling discrimination between C and DS groups. Hence, Q-factor was the ultrasonic parameter that showed statistically significant differences between C and DS groups at days 3 and 7. Consequently, Signal Intensity in Q during the drought treatment showed a similar evolution to Ψ leaf , although with slightly lower performance. However, Q-factor sensitivity excels Ψ leaf at each day studied. Finally, a linear correlation (R2=0.57) between Ψ leaf and Q-factor of all experimental data measured in DS group plants along the drought treatment was found. In conclusion, the ultrasonic parameters obtained using NC-RUS and in particular the Q-factor, demonstrated to be potential new water stress indicators in Citrus trees, with the novelty of being non-destructive, non-invasive and rapid. Future work should explore its suitability for its use in irrigation scheduling for Citrus trees. [Display omitted] [ABSTRACT FROM AUTHOR]

Semi-arid regions often face severe drought events that reduce agricultural and livestock production. In recent years, some international studies have used multicriteria decision analysis (MCDA) approaches combined with geographic information systems (GIS-MCDA) to support decision-makers in assessing the suitability of agricultural land for irrigation in semi-arid regions. Unlike previous studies, which have only considered a single source of water for crop irrigation, this study proposes a GIS-MCDA approach that considers all potentially available local water sources (e.g., groundwater, surface water, and wastewater) as possible alternatives for better multisource water resource management (MWRM) in regions facing water shortages. The geospatial multicriteria evaluation implemented in this study considers a series of technical, environmental, and agricultural productivity criteria using the analytical hierarchy process (AHP) method. Three independent baseline maps were generated, showing the spatial distribution of suitable areas for crop irrigation for each considered water source in the studied area. Surface water, groundwater, and wastewater offered suitable crop irrigation for 83%, 70%, and 26% of the study area, respectively. Overlapping these areas produced a final map showing all the feasible areas for each crop irrigation alternative at the same time. The MWRM approach considering all water sources increased the coverage of suitable areas to be irrigated in the study area by 2.2%, 20.4%, and more than 225% compared to considering surface water, groundwater, and wastewater, respectively, independently. The GIS-MCDA framework proposed in this study provides better support for decision-makers and stakeholders, favouring a reduction in possible conflicts over water scarcity, the diversification of irrigated crops, and an improvement in the quality-quantitative management of water resources in semi-arid regions. • A GIS-MCDA approach to assess the suitability of agricultural lands for irrigation. • Three sources of water were considered in the approach for better water management. • Analysis of combined water resources increased the resulting areas suitable for irrigation. • The proposed analytical approach provides better support for irrigation in semi-arid regions. [ABSTRACT FROM AUTHOR]

Brewery effluent (BE) can be used as a water and nutrient source for crop irrigation. It contains high levels of nitrogen and phosphorus, which are essential plant nutrients. However, the effluent at Ibhayi Brewery (SAB Ltd) has a high concentration of sodium, which is a constraint for its reuse in agriculture. The objectives here were to determine the salt removal efficiency, crop growth and health and changes in soil structure when four salt-tolerant test crops were irrigated with BE and subjected to crop rotation or soil amendments. These crops included Swiss chard (Beta vulgaris), saltbush (Atriplex nummularia), Salicornia meyeriana and sorghum (Sorghum bicolor), and all grew efficiently in BE irrigated soils but did not stop sodium accumulation in the growth medium. Nitrogen was successfully exploited, while phosphorus availability was limited by an unfavourable pH. Swiss chard had the best growth with a wet biomass production of 8173 g m-2 , due to the plant's ability to tolerate saline conditions and continuous cropping. Crop rotation, aiming to limit the effects of nutrient depletion in soil, had no significant effect on plant growth, suggesting that the soils were provided enough micro-nutrients in the short term. Prolonged irrigation with BE can lead to sodium accumulation in the soil, which was successfully ameliorated through addition of soil amendments (gypsum and Trichoderma). These amendments reduced soil sodium from a potentially yield limiting level of 1398 mg L-1 to the acceptable levels of 240 mg L-1 and 353 mg L-1, respectively, mainly through leaching. However, only the addition of Trichoderma improved Swiss chard production to 11,238 g m-2, while reducing soil surface crusting and improving infiltration rates. Soil amended with Trichoderma appears to be a potential solution for BE reuse as a water and nutrient source in agriculture. • Brewery effluent is a suitable water and nutrient source for salt tolerant plants such as Swiss chard. • Swiss chard can take up soil sodium. • Trichoderma can reduce sodium buildup in the soil. • Trichoderma improves soil properties such as infiltration rate and compaction, improving crop growth in the short term. • soil amended with Trichoderma appears to be a potential solution when brewery effluent is reused in agriculture. [ABSTRACT FROM AUTHOR]

• This manuscript provides a planning tool for reclaimed water use in agriculture to alleviate pressure on freshwater sources. • A GIS-MCDA framework was developed to produce the agricultural land suitability maps for irrigation with reclaimed water. • Multiple qualitative and quantitative decision criteria were included in the developed GIS-MCDA. • The developed decision framework was tested at a large scale (State of California) with multiple crop patterns. • Proximity to reclaimed water source and crop type were the most influential criteria for irrigation with reclaimed water. Water scarcity, climate variability and continuing growth in water demand have put severe pressure on high‐quality freshwater sources. This challenge exacts the necessity to explore alternative water sources for agricultural irrigation. The objective of this study was to implement the integrated geospatial Multi-Criteria Decision Analysis (MCDA) with the Analytical Hierarchy Process (AHP) to evaluate the potentiality of reclaimed water use for agricultural irrigation in California. Five evaluation criteria included in this study were agricultural land (crop type), climate conditions, water policies, irrigation status, and proximity to wastewater treatment plants (WWTPs) respectively. The suitability maps for reclaimed water use were generated for three cases in terms of accessibility to WWTPs, their discharge volume and appropriate treatment processes respectively. In addition, a composite suitability map was produced using the hybrid model considering all three cases together. Results from this study led to a better understanding of sustainable reclaimed water use for crop irrigation at a regional level. It provided supporting evidence of the applicability of the GIS-MCDA method integrated with AHP technique for a larger geographical scale with a diverse crop pattern. This study established the importance of using both knowledge-based and data-driven criteria and sub-criteria in the decision framework. The results also highlighted how the spatial distribution of suitable areas for reclaimed water reuse is closely linked to the agricultural areas. [ABSTRACT FROM AUTHOR]

The increasing shortage of water for crop irrigation in arid and semiarid regions is encouraging the use of non-conventional resources. In the last decade, seawater desalination has consolidated its position as an alternative source to increase the supply for agricultural irrigation in Spain and Israel, where the farmers' acceptance is progressively rising, despite the supply price being much higher than that of other conventional water sources. This article describes the current situation of desalinated seawater production and supply to agriculture in the southeast of Spain, and analyzes key questions such as its role in regional water planning, the infrastructure needed for conveyance and distribution, the energy requirements, the production and distribution costs, and the final price to farmers. The study is based on descriptive and quantitative data collected from desalination plants and irrigation district managers through technical questionnaires and personal interviews. The results show how seawater desalination is effectively alleviating the regional constraints in the irrigated agriculture supply, and why it is becoming strategic to maintaining food production and socioeconomic development. However, the high-energy requirements and associated costs in comparison with other water sources limit a more widespread use for agriculture, and for this reason desalinated water still only plays a complementary role in most irrigation districts. [ABSTRACT FROM AUTHOR]

Climate change is a proven fact. In the report of 2007 from IPCC, one can read that global warming is an issue to be dealt with urgently. In many parts of the world, the estimated rise of temperature (in a very near future) is significant. One of the most affected regions is the Iberian Peninsula, where the increasing need for water will very soon be a problem. Therefore, it is necessary that decision makers are able to decide on all issues related to water management. In this paper, we show a couple of mathematical models that can aid the decision making in the management of an agricultural field at a given location. Having a field, in which different crops can be produced, the solution of the first model indicates the area that should be used for each crop so that the profit is as large as possible, while the water spent is the smallest possible guaranteeing the water requirements of each crop. Using known data for these crops in Portugal, including costs of labour, machines, energy and water, as well as the estimated value of the products obtained, the first mathematical model developed, via optimal control theory, obtains the best management solution. It allows creating different scenarios, thus it can be a valuable tool to help the farmer/decision maker decide the crop and its area to be cultivated. A second mathematical model was developed. It improves the first one, in the sense that it allows considering that water from the rainfall can be collected in a reservoir with a given capacity. The contribution of the collected water from the rainfall in the profit obtained for some different scenarios is also shown. [ABSTRACT FROM AUTHOR]