Appraisal of the geostatistical methods to estimate Mazandaran coastal ground water quality

The present study was carried out to evaluate three interpolation methods including weighted moving average (WMA) with the power of 2 and 3, Kriging and Cokriging methods. Data of 23 wells in Mazandaran province were collected in fall and spring 2006. Seven parameters including electrical conductivity (EC), pH, total dissolved solids (TDS), sodium adsorption ratio (SAR), total hardness (TH), chloride concentration (Cl- ) and sulphate concentration (SO4 2- ) have been chosen as groundwater quality indices in the study area. Variogram analysis and extracting the spatial distribution maps of groundwater quality parameters were done using Geostatistics extension program in GIS environment. All interpolation methods have been evaluated based on mean bias error (MBE) and mean absolute error (MAE) criteria. The spherical model for semi-variograms had the less value of RSS (residual sum of square) for Cl- , EC, pH, SAR and SO4 2- parameters. TDS and TH parameters followed a Gaussian model. All semi-variograms and cross variograms had high confident level due to little values of nugget effects (Co) relative to sill. The covariance matrix demonstrated that magnesium concentration (Mg2+), sodium concentration (Na+), Total anions, Cl- , EC and TDS parameters have been the best covariate for estimating TH, SO4 2- , Cl- , PH, TDS and EC parameters, respectively. Co-Kriging was the best method for estimating all parameters far apart TH for which Kriging method was the best. Spatial distribution maps of groundwater quality indices demonstrated that the groundwater in the study area is slightly basic and the values of EC exceeded the permeable limit in more than 40% of the study area. Also there was sodium hazard and high concentration of TDS in the north-east part. Therefore, further studies are needed to recognize the pollution sources in order to reclaim the polluted part in the study area

Agro-economic and socio-environmental assessments of food and virtual water trades of Iran

Ending hunger and ensuring food security are among targets of 2030 s SDGs. While food trade and the embedded (virtual) water (VW) may improve food availability and accessibility for more people all year round, the sustainability and efficiency of food and VW trade needs to be revisited. In this research, we assess the sustainability and efficiency of food and VW trades under two food security scenarios for Iran, a country suffering from an escalating water crisis. These scenarios are (1) Individual Crop Food Security (ICFS), which restricts calorie fulfillment from individual crops and (2) Crop Category Food Security (CCFS), which promotes eating local by suggesting food substitution within the crop category. To this end, we simulate the water footprint and VW trades of 27 major crops, within 8 crop categories, in 30 provinces of Iran (2005 2015). We investigate the impacts of these two scenarios on (a) provincial food security (FSp) and exports; (b) sustainable and efficient blue water consumption, and (c) blue VW export. We then test the correlation between agro-economic and socio-environmental indicators and provincial food security. Our results show that most provinces were threatened by unsustainable and inefficient blue water consumption for crop production, particularly in the summertime. This water mismanagement results in 14.41 and 8.45 billion m3 y-1 unsustainable and inefficient blue VW exports under ICFS. Eating local improves the FSp value by up to 210% which lessens the unsustainable and inefficient blue VW export from hotspots. As illustrated in the graphical abstract, the FSp value strongly correlates with different agro-economic and socio-environmental indicators, but in different ways. Our findings promote eating local besides improving agro-economic and socio-environmental conditions to take transformative steps toward eradicating food insecurity not only in Iran but also in other countries facing water limitations. © 2021, The Author(s).We would like to thank the reviewers of the manuscript for their constructive comments. Thanks to Ms. Manuela Rosso—Brugnach for proofreading the article. This Project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Earth@lternatives Project, Grant agreement No 834716). Brugnach is supported by the Spanish Government through María de Maeztu excellence accreditation 2018–2022 (Ref. MDM-2017-0714) of BC3

Agricultural Adaptation to Reconcile Food Security and Water Sustainability Under Climate Change:The Case of Cereals in Iran

In this study, we simulate the crop yield and water footprint (WF) of major food crops of Iran on irrigated and rainfed croplands for the historical and the future climate. We assesse the effects of three agricultural adaptation strategies to climate change in terms of potential blue water savings. We then evaluate to what extent these savings can reduce unsustainable blue WF. We find that cereal production increases under climate change in both irrigated and rainfed croplands (by 2.6-3.1 and 1.4-2.3 million t y-1, respectively) due to increased yields (6.6%-78.7%). Simultaneously, the unit WF (m3 t-1) tends to decrease in most scenarios. However, the annual consumptive water use increases in both irrigated and rainfed croplands (by 0.3-1.8 and 0.5-1.7 billion m3 y-1, respectively). This is most noticeable in the arid regions, where consumptive water use increases by roughly 70% under climate change. Off-season cultivation is the most effective adaptation strategy to alleviate additional pressure on blue water resources, with blue water savings of 14-15 billion m3 y-1. The second most effective is WF benchmarking, which results in blue water savings of 1.1-3.5 billion m3 y-1. The early planting strategy is less effective, but still leads to blue water savings of 1.7-1.9 billion m3 y-1. In the same order of effectiveness, these three strategies can reduce blue water scarcity and unsustainable blue water use in Iran under current conditions. However, we find that these strategies do not mitigate water scarcity in all provinces per se, nor all months of the year

Arjen Y. Hoekstra: A Water Management Researcher to Be Remembered

On 18 November 2019, the life of Arjen Y [...

Obese and female adolescents skip breakfast more than their non-obese and male peers

We examined the association between overweight/gender and skipping breakfast among adolescent students in Tehran city using a cross-sectional study and a multistage random sampling method. All educational zones in Tehran city were covered during the educational year of 2000-01. In total, 2321 students aged 11-16 years (1068 male; 1263 female) participated in the study. Weight and height were measured and body mass index (BMI; kg/m2) was calculated. Overweight, pre-obesity and obesity were defined as BMI � 85 th , 85 th to 95 th , and � 95 th percentile of age-sex-specific BMI reference values, respectively. Self-reported frequency of breakfast consumption was categorized as usual/always, often, and rarely/never (5-7, 2-4 and 0-1 times/wk, respectively). Student's t and Chi-square tests were employed to analyze the data. Statistical inferences were made at α = 0.05. In boys and girls, the mean ± standard deviation of BMI was 19.8 ± 4.0 and 20.6 ± 4.1 kg/m2, the 18.8 and 23.1 were overweight, and 7.3 and 8.3 were obese, respectively. There was a significant difference in the frequency of breakfast consumption between obese and normal male students (P < 0.001). Differences between pre-obese and normal, and obese and normal female students were also significant (P < 0.002 and P < 0.001, respectively). A significant difference was found in the frequency of breakfast consumption between male and female adolescents in all three categories (P < 0.001). These results suggest that obese and female adolescents are more likely to skip breakfast than their normal and male peers and are therefore at higher risk for growth deficits and low educational performance. Preventive/educational programs are urgently needed in this age group. © 2007 Versita Warsaw and Springer-Verlag

Core shell lipid-polymer hybrid nanoparticles with combined docetaxel and molecular targeted therapy for the treatment of metastatic prostate cancer

Many prostate cancers relapse after initial chemotherapy treatment. Combining molecular and chemotherapy together with encapsulation of drugs in nanocarriers provides effective drug delivery and toxicity reduction. We developed core shell lipid-polymer hybrid nanoparticles (CSLPHNPs) with poly (lactic-co-glycolic acid) (PLGA) core and lipid layer containing docetaxel and clinically used inhibitor of sphingosine kinase 1 (SK1) FTY720 (fingolimod). We show for the first time that FTY720 (both free and in CSLPHNPs) re-sensitizes castrate resistant prostate cancer cells and tumors to docetaxel, allowing a four-fold reduction in effective dose. Our CSLPHNPs showed high serum stability and a long shelf life. CSLPHNPs demonstrated a steady uptake by tumor cells, sustained intracellular drug release and in vitro efficacy superior to free therapies. In a mouse model of human prostate cancer, CSLPHNPs showed excellent tumor targeting and significantly lower side effects compared to free drugs, importantly, reversing lymphopenia induced by FTY720. Overall, we demonstrate that nanoparticle encapsulation can improve targeting, provide low off-target toxicity and most importantly reduce FTY720-induced lymphopenia, suggesting its potential use in clinical cancer treatment

Two-dimensional modeling of nitrogen and water dynamics for various N-managed water-saving irrigation strategies using HYDRUS

Nitrate losses are the dominant cause of the non-point source pollution under agricultural fields. In this study, the HYDRUS-2D model was first calibrated and validated using data collected during a two-year field investigation in a drip-irrigated maize field and then applied to evaluate the influence of 176 different N-managed water-saving irrigation scenarios on water and N dynamics and maize grain yield. Various scenarios were defined by combining 11 irrigation levels (IL = 0–100% with a 10% interval), 8 N fertilization rates (NR = 0–400 kg ha−1 with a 50 kg ha−1 interval) and two water-saving irrigation strategies: deficit irrigation (DI) and partial root-zone drying (PRD). Reliable estimates of soil NO3−-N concentrations (RMSE = 0.39–10.9 mg l−1 and MBE = −8.9–8.4 mg l−1), crop N uptake (RMSE = 3.9–8.9 kg ha−1 and MBE = −5.3–6.25 kg ha−1), and soil water contents (RMSE = 2.3–5.11 mm and MBE = 1.63–4.93 mm) were provided by HYDRUS-2D. Based on the simulated results, the fertigation strategy with NR = 200 kg ha−1 is an optimum strategy. For the higher fertigation rates (NR ≥ 250 kg ha−1), the NO3−-N leaching out of the surface layers (0–20 cm) increased by 0.1–183% while N uptake was enhanced by only 0.3–15%. On the other hand, reducing NR below this level would have resulted in severe economic losses. A 30% reduction in IL at NR = 200 kg ha−1 shows an enormous potential in lowering N leaching below different soil layers (12–99%) while reducing crop N uptake by only 5.4%. In addition, higher crop yield by 0.2–20.2% can be expected under PRD since crop N uptake is enhanced by more water available in the surface layers. While on the one hand, PRD ensures environmentally safer fertilizer applications, on the other hand, the economic objectives are met more easily under PRD than under DI. Additionally, it could be concluded that the HYDRUS-2D model, instead of labor- and time-consuming and expensive field investigations, could be reliably used for determining the optimal scenarios under both the DI and PRD strategies

An application of the water footprint assessment to optimize production of crops irrigated with saline water: A scenario assessment with HYDRUS

Agriculture, due to a growing scarcity of fresh water resources, often uses low-quality waters for irrigation, such as saline waters. However, unmanaged applications of such waters may have negative environmental and economic consequences. Based on the concept of the water footprint (WF), a measure of the consumptive and degradative water use, the field-calibrated and validated HYDRUS (2D/3D) model was applied to find optimal management scenarios (from 1980 different evaluated scenarios). These scenarios were defined as a combination of different salinity rates (SR), irrigation levels (IL, the ratio of an actual irrigation water deth and a full irrigation water depth), nitrogen fertilization rates (NR), and two water-saving irrigation strategies, deficit irrigation (DI) and partial root-zone drying (PRD). The consumptive WF was defined as the crop water consumption divided by the crop yield. The grey WF was calculated for the N fertilizer and defined as the volume of freshwater required to dilute nitrogen (N) in recharge so as to meet ambient water quality standards. Simulated components of water and solute dynamics were used to calculate criteria indices, which were divided into two groups: (a) environmental indices, including the degradative grey water footprint (GWF) and the apparent N recovery rate efficiency (ARE), and (b) economic indices, including economic water (EWP) and land (ELP) productivities. While significant improvements of 3.9–59.2%, 0.1–165.8%, and 0.01–166.5% in ARE, EWP, and ELP, respectively, were obtained when NR varied within the range of 0–200 kg ha−1, changes in these indices were relatively minor when NR was higher than 200 kg ha−1. At a given NR, GWF tends to increase considerably by up to 180% when DI-crops are subject to low-intermediate salt (SR < 7 dS m−1) and water (IL > 70%) stresses. This is at the expense of up to a 55% reduction in ELP and up to a 120% increase in EWP. With N uptake 0.2–17.3% higher, PRD seems to be a more viable agro-hydrological option than DI in reducing a pollutant load into regional aquifers as well as in sustaining farm economics. The entire analysis reveals that the PRD strategy with N-fertilization rates of 100-200 kg ha−1, a moderate salinity stress (SR < 5 dS m−1), and irrigation levels of 60–90% represents the best management scenario. It can be concluded that, while there is a substantial need for rescheduling irrigation and fertilization managements when crops are irrigated with saline waters, HYDRUS modeling may be a reliable alternative to extensive field investigations when determining the optimal agricultural management practices

A field-modeling study for assessing temporal variations of soil-water-crop interactions under water-saving irrigation strategies

Simulation models are useful tools that may help to improve our understanding of soil-water-plant interactions under innovative water-saving irrigation strategies. In this study, the HYDRUS-2D model was applied to evaluate the influence of deficit irrigation (DI) and partial root-zone drying (PRD) on maize water extractions during two cropping cycles of 2010 and 2011. The model was calibrated and validated using measured soil water content data (expressed as equivalent water depths). Reliable estimates of soil water content were provided by HYDRUS-2D, with root mean square error and mean bias error values of 2.3–5.11 and 1.63–4.93 mm, respectively. Root water uptake and maize grain yields were reduced by 13.2–28.8% and 13.6–52.8%, respectively, under different water-saving irrigation treatments compared to full irrigation. However, different root and water repartitions in the PRD treatment with a 25% reduction in the irrigation depth (PRD75) improved soil water utilization and consequently, crop growth. Increased root water uptake (2.2–4.4 times higher than in other treatments) from the 60–100 cm soil depth in the PRD75 treatment maintained a favorable daily evapotranspiration rate, resulting in no significant reduction in maize grain yield compared to full irrigation. Consequently, a 15.7–85% increase in water use efficiency for maize cultivation under PRD75 ensured 25% water savings without threatening food security in the study area. It can be concluded that HYDRUS-2D can be successfully used to optimize water management under local water-stress conditions