mojtaba khoshravesh

The surface temperature of the Earth is rising, and due to climate change, this trend is expected to continue. This study investigates the effects of climate change on climatic variables using the MRI ESM2.0 climate prediction model in accordance with the sixth CMIP6 report in Lordegan and Borujen, employing temperature and precipitation data recorded at these two stations from 2000 to 2014. Subsequently, future atmospheric conditions were forecasted for two twenty-year periods: the near future (2020-2040) and the distant future (2040-2060), based on three designed emission scenarios—optimistic (SSP1-2-6), intermediate (SSP2-4-5), and pessimistic (SSP5-8-5). By comparing the parameters of the baseline period with the predicted future values, the Borujen and Lordegan stations are expected to see an increase in average minimum temperatures ranging from 1.3 degrees Celsius in the optimistic scenario during the near future to approximately 2.6 degrees Celsius in the pessimistic scenario in the distant future compared to the baseline period. For maximum temperatures, an increase between 1.2 and 3.1 degrees Celsius is observed across all selected scenarios. Specifically, the projected reduction in precipitation for Borujen is estimated to range from 7.5% to 11%, while for Lordegan, it is expected to vary from 12% to 14.7%. The results of this study can contribute to future water resource management, establish effective programs to address climate change, and prepare the ground for informed decision-making and appropriate planning

The increasing development of industries and the growing use of fossil fuels are leading to an increase in the concentration of greenhouse gases, particularly carbon dioxide, which in turn is causing global warming. Therefore, the aim of this research is to investigate the impact of climate change on the climatic variables of Shahrekord station using the CanESM5 climate prediction model, in accordance with the CMIP6 Sixth Assessment Report. To this end, based on the climatic data of temperature and precipitation recorded at the synoptic station of Shahrekord Airport during the baseline period of 1995-2014, and the designed emission scenarios including three scenarios – optimistic SSP1-2-6, moderate SSP2-4-5, and pessimistic SSP5-8-5 – the future weather conditions were predicted for two twenty-year periods, near future (2025-2045) and far future (2046-2066). To downscale the predicted values, the SDSM5.2 statistical downscaling method was used. Subsequently, the performance of the CanESM5 model for simulation was evaluated using appropriate statistical metrics. The simulation results of CanESM5 showed that there is less error and higher accuracy for predicting minimum and maximum temperatures compared to precipitation. According to the findings of the present study, it is predicted that the studied station, compared to the baseline period, will experience an increase in future precipitation of up to 6.5% in optimistic scenarios and a decrease in precipitation of up to 16% in pessimistic scenarios throughout the year for all emission scenarios. Additionally, the range of maximum temperature variations in the far future experiences more fluctuations compared to the near future, and there will also be a slight decrease in the average annual minimum temperature in the near future and an increase in the far future.

The selection of landfill sites and the utilization of modern sanitary burial methods must consider the environmental regulations of each country. Given the impacts that landfill sites have on ecosystems and their surrounding environments, it is essential to ensure that the location chosen for landfill minimizes destructive effects and adverse impacts on its surroundings. The objective of the present study was to identify suitable locations for the disposal of industrial waste in Mazandaran Province. Iran. In selecting waste disposal sites, all environmental, geological, hydrological, topographic, physiographic, climatic, soil science criteria, protected areas, buffer zones for oil, water and power transmission lines, access roads, population areas, and other criteria stipulated in legal regulations were considered. The spatial analysis of the results of this study showed that 22.6% of the area of Mazandaran Province conflicts with 15 environmental criteria. The results from overlaying the prepared informational layers, while adhering to each technical standard for establishing an industrial and special waste storage center using the Boolean method, indicated that none of the areas in Mazandaran Province meet the current technical standards for establishing a special waste storage center, and it is not feasible to establish such a center in Mazandaran Province.

In this study, AquaCrop model was employed to simulate the grain yield of pea plants under future climate conditions, considering various irrigation treatments and different planting dates as an adaptation strategy, in Babol County, Iran. The grain yield and biomass of pea plants were simulated for the next three decades for planting dates of October (16, 23, and 30), November 6, 13, 20, and 27), under future climate scenarios of 126SSP, 245SSP, and 585SSP of Intergovernmental Panel on Climate Change (IPCC) Sixth Report, and three levels of irrigation: 100% (I1), 80% (I2), and 60% (I3). According to the results, the highest pea yield in the 2023-32 was simulated for the I1 treatment under the 585SSP scenario on November 6, yielding 7.2 t/ha, while the lowest yield was simulated for the I3 treatment under the same scenario on November 27, yielding 4.1 t/ha. In 2033-42, the highest yield was observed for I1 under the 585SSP scenario on November 13, yielding 8.4 t/ha, and the lowest yield for I3 under the 245SSP scenario on November 27, yielding 4.4 t/ha. In the 2043-52, the highest yield was simulated for I1 under the 585SSP scenario on November 9, yielding 8.7 t/ha, while the lowest yield belonged to I3 under 126SSP on October 16, yielding 3.9 t/ha. The highest pea biomass in 2023-32 was simulated for I1 under the 585SSP scenario on November 13, yielding 17.1 t/ha, while the lowest biomass belonged to I3 under the same scenario on November 27, yielding 10.3 t/ha. In 2033-42, the highest biomass was simulated for I1 under the 585SSP on November 20, yielding 20.1 t/ha, and the lowest biomass for the I3 under the 245SSP scenario on November 27, yielding 11.1 t/ha. In 2043-52, the highest biomass was for the I1 under the 126SSP scenario on November 13, yielding 20.6 t/ha, while the lowest biomass was observed for I3 under the 245SSP on November 27, yielding 12.7 t/ha. Therefore, the optimal planting dates for pea crops in Babol County are October 30, November 6 and 13, under the I1 irrigation, which can help improve crop and irrigation management in this region. Overall, climate change can lead to both increases and decreases in pea yield and biomass, but with proper irrigation management and selection of the optimal planting dates, the likelihood of yield increase is higher.

Since flooded rice fields are considered one of the major sources of methane production in agriculture, optimizing water and planting practices can help to reduce the emission of this gas. This study aimed to investigate the interaction effects of different rice planting methods and irrigation systems on yield and methane emissions in paddy fields. The experiment was conducted as a split-plot design within a randomized complete block design with three replications during the years 2019 and 2020 in Gorgan County. Four irrigation treatments, including sprinkler irrigation, continuous flooding, intermittent flooding, and tape irrigation, were applied as the main factor, while three planting methods, including direct planting, transplanting in non-puddled soil, and transplanting in puddled soil, were considered as sub-factors. The effects of planting year, irrigation system, and planting method on grain yield were significant at the 1% probability level. The highest grain yield was observed in the transplanting method on puddled soil, with a yield of 7,506 kg/ha. Grain yields under intermittent flooding, tape, and sprinkler irrigation systems decreased by 6.46%, 15.6%, and 39.03%, respectively, compared to continuous flooding. Among the different planting methods, the highest methane emission was recorded in the transplanting method on puddled soil, with 2.73 mg/m². Methane emissions in the transplanting method on non-puddled soil and direct seeding were reduced by 10.08% and 24.65%, respectively, compared to the transplanting on puddled soil. The lowest methane emission was observed in the tape irrigation system, with 0.42 mg/m². Methane emissions under intermittent flooding were 39% lower than in continuous flooding. Overall, optimizing irrigation management and planting methods in rice fields can significantly reduce methane emissions, thereby contributing to mitigating the effects of climate change. Based on the present study, the most effective approach is drip tape irrigation combined with non-puddled transplanting.

Given the increasing population and the growing demand for food, the development of agriculture is essential. Due to the limitations of water resources, managing water in agriculture is highly important and should be considered at every stage of agricultural production. This study conducted the experiment in a factorial design within a randomized complete block design with three replications. The irrigation factor was tested at three levels (100% FI (I1), 80% FI (I2), and 60% FI (I3)), and water salinity at three levels (well water (S1), 20 mM or 2.52 dS/m sodium chloride (S2), and 40 mM or 5.06 dS/m sodium chloride (S3)) in two conditions: non-magnetized (W1) and magnetized (W2) water. The effects of irrigation levels, salinity, and the type of irrigation water on the quality characteristics of strawberry fruit, including total protein, chlorophyll a, chlorophyll b, total chlorophyll, total soluble solids, titratable acidity, vitamin C, and sugar content, were examined. The analysis of variance results showed that all factors had a significant impact on the quality characteristics of strawberry fruit at the (p<0.01). Among the different irrigation levels, the highest amounts of total protein, chlorophyll a, chlorophyll b, and total chlorophyll were 5.09, 2.39, 1.05, and 3.44 mg per gram, respectively, in the 100% irrigation treatment, while among the different salinity levels, these values were 5.13, 2.49, 1.11, and 3.61 mg per gram, respectively, in the well water treatment. Magnetized water also had a significant effect at the 1% probability level on the quality characteristics of strawberry fruit.

The use of groundwater for agricultural, industrial, and drinking purposes is significantly increasing worldwide. These resources are considered an important part of the renewable water ecosystem and have various advantages over surface waters, such as higher quality and less contamination. However, recent intermittent droughts and a noticeable decrease in surface water resources have led to the excessive use of groundwater sources and a decline in their quality. Therefore, understanding the quality of groundwater is crucial for proper planning and management of these resources and requires serious attention and detailed analysis. Additionally, one of the health problems in developing areas is the lack of access to safe drinking water, and human health is at the core of sustainable development in the region. Therefore, ensuring the welfare and health of the community at an acceptable level is not possible without access to clean and standardized drinking water. Water is important from both health and economic perspectives as it serves as a catalyst for industrial growth and the prosperity of the agricultural sector. In this regard, this research aims to evaluate and analyze the quality and spatial changes in groundwater quality based on the GQI assessment index.

This research focuses on evaluating and analyzing spatial changes in groundwater quality within the study areas of Khanmirza, Lordegan, Boroujen, Ardal, and Kiar, located in  Chaharmahal and Bakhtiari province, for drinking purposes. Practical information is provided regarding the status of available water resources in the region for drinking purposes. To this aim, 28 groundwater samples were collected from legally operating wells in various locations within the mentioned counties during the  2020-2021 period and subjected to chemical analysis in the laboratory. The GQI (Groundwater Quality Index) was used to assess the quality of these samples for drinking purposes. In this study, the GQI was calculated based on the concentration values of 11parameters, including electrical conductivity, acidity, total dissolved salts, calcium ion, sodium, magnesium, potassium, carbonate, bicarbonate, chloride, and sulfate. Subsequently, spatial zoning of the overall parameter values was performed using the chemical characteristics of the collected samples and employing the inverse distance weighting (IDW) interpolation method in the GIS software environment, and the desired information layers were obtained in raster format. Furthermore, overlays were performed by applying computational functions to the available information layers,, followed by estimating the GQI values and preparing raster maps of the index. The output maps can be utilized not only to determine the qualitative characteristics within the study area but also to analyze the trends of their variations, prepare zoning maps for  each parameter, and compare them with standard values.

The calculated GQI using measured samples categorizes a significant portion of the  study area within the excellent and good quality categories suitable for drinking. Additionally, the color spectrum of the zoning map indicates better water quality in the western and southern  parts of the study area than in the other sections. Generally, water quality decreases from the south toward the north and northeast. The sensitivity analysis of the model focuses on examining the impact of changing one input variable on a model's output variable. The sensitivity analysis revealed that parameters such as acidity, calcium, magnesium, total dissolved salts, and electrical conductivity had a negative effect (meaning an increase in index values and water quality improvement after removing these parameters and deterioration with their addition in the index calculation). Conversely, the concentrations of bicarbonate ions, sulfate, sodium, potassium, and chloride had a positive impact on water quality (meaning a decrease in index values and deterioration after removing these parameters and improvement with their addition in the index calculation). These parameters have allocated the highest to lowest changes in estimating the GQI index. Therefore, the GQI quality index shows greater sensitivity to the presence or absence of acidity and calcium bicarbonate than the other parameters used in determining the index, influencing decision-making regarding the classification of drinking water quality more than the other parameters. Despite having higher weights in calculating the index, some parameters show insignificant percentage changes in the index due to their presence or absence. For example, despite a lower weight of bicarbonate than magnesium ions, it shows a higher percentage change in the index after its removal than the percentage change caused by removing magnesium. Thus, higher weights for these components do not necessarily imply greater sensitivity of the model to them.

The results of this study indicate that the groundwater quality in the studied areas is suitable for drinking purposes, and the groundwater in the study area has not been affected by changes resulting from the tested parameters in the drinking sector. Additionally, this study contributes to comprehensive and useful planning for the management and conservation of groundwater resources, enabling more informed decision-making based on groundwater quality maps in this regard.

water resources limitations in the country and the need for healthy food have led to an increased focus on the multifunctional use of water resources, as well as fish production, to meet human needs and improving the economic capacity of farmers. Additionally, aquaculture wastes are valuable fertilizers to enhance agricultural products . Therefore, the aim of this research is to investigate the effect of irrigating with wastewater from red tilapia fish ponds on yield and yield components of Persian Leek (Allium persicum L.). The current experiment was conducted in the research greenhouse of the water engineering department at the Agricultural Sciences and Natural Resources University of Gorgan. The experiment aimed to examine three water quality levels (city water, a 50:50 mixture of pond wastewater and city water, and fishery wastewater) in a completely randomized design based on pot cultivation and performed in  four replications. Results showed that irrigation  water quality had a significant affect on fresh and dry root weight, plant height, fresh weight of the plant, and leaf count per plant at the 1% probability level. while the dry weight of the plant and root length were significant at the 5% probability level. The results indicated that all the mentioned traits increased with the increase in the amount of fishery wastewater. Based on the results, the highest fresh aerial organ weight (13.97 g), fresh root weight (8.58 g), and aerial organ height (26.55 cm) were observed with irrigation using fish pond wastewater. The 50% mixture treatment of fish pond wastewater and city water led to a 5.72% increase in the aerial organ weight of Persian leek plant compared to the city water treatment. Additionally,  since fish pond wastewater essential  nutrients needed for plant growth, using fish pond wastewater in Persian leek plant cultivation is recommended, while further studies are needed for other vegetables.

Discharge and disposal of wastewater containing high nitrate levels contribute to its increase in groundwater and water resources, posing adverse effects on the environment and human health. An experiment was conducted at laboratory water quality, Sari Agricultural Sciences and Natural Resources University, to investigate the impact of ultrasonic waves on nitrate removal and the absorption properties of rice straw biochar absorbents. Various treatments were applied, including ultrasound alone (U), biochar absorbent (B), biochar absorbent with ultrasound (BU), iron-coated biochar absorbent (BF), iron-coated biochar absorbent with ultrasound (BFU), zinc cation-coated biochar absorbent (BZ), and ultrasound with rice straw biochar coated with zinc cations (BZU). Results showed that ultrasonic waves effectively removed nitrates from the aqueous solution and enhanced the nitrate absorption process by the absorbent. In the iron and zinc-coated biochar absorbents, ultrasonication increased the optimal pH of the nitrate solution. The biochar and zinc-coated biochar absorbents exhibited a reduction in the optimal absorbent dose, and the optimal initial nitrate concentration in zinc-coated biochar increased from 80 ppm to 150 ppm. Overall, a 27% reduction in nitrate concentration was observed in the solution. Considering the results, a combined use of ultrasonication is recommended for a more efficient decomposition of pollutants.

Given the extensive cultivation of maize in Iran, any initiative aimed at increasing water use efficiency contributes to reducing water consumption and enhancing food security in the country. One of the most influential factors affecting the growth and performance of crops is the impact of climate change. The present study aims to assess the impact of climate change and altering planting dates on the water productivity of maize in Gorgan County. Additionally, water productivity of maize under different irrigation treatments and planting dates is simulated using the WOFOST model for future conditions. The irrigation treatments include 100% (T1), 75% (T2), and 50% (T3) of the plant's water requirements. Hence, statistical SDSM and HadCM3 General Circulation Model were employed to downscale all scenarios of the fifth report for two thirty-year periods, 2020-2050 and 2050-2080. The results showed with increasing of irrigation water stress, the simulation error of irrigation water productivity increased, but no consistent trend was observed. In the period of 2050-2020, the highest irrigation water productivity was predicted in treatment T3 on 23 June, amounting to 4 kilograms per cubic meter, which represents a 1.9% reduction compared to the baseline period. During this period, the lowest irrigation water productivity was projected in treatment T1 on 2 June, amounting to 2.7 kilograms per cubic meter, indicating a 57.3% reduction compared to the baseline. Based on the simulated results, the optimal planting time for corn in Gorgan is on 23 June. With appropriate validation of the planting date, effective management can be implemented to adapt to the negative effects of climate change on corn water productivity. Choosing the best planting time, along with proper management, is an efficient solution in Gorgan to prevent reduced performance due to an inappropriate choice of planting date.

Considering the importance of fresh water for human life and the vulnerability of groundwater sources to all kinds of pollution and the possibility of transferring pollutants to other surface and groundwater sources, as well as the location of Iran in the arid and semi-arid belt, protecting this valuable and rare element is imperative and its continuous monitoring must be one of the priorities of water resources managers. Therefore, in the current research, nitrate pollution in the eastern plains of Mazandaran province was discussed and relevant issues were investigated, and an efficient and optimal model for predicting nitrate concentration was presented. In this research, three machine learning models including decision tree, logistic regression and artificial neural network were compared. The physical and chemical data measured during the years 1985 to 2020 were used and entered as the input variables of the models. The variables include temperature, water level, pH, EC, HCO3-, CL-, SO24-, Na+, K+, Mg2+, Ca2+, TH and TDS; The amount of nitrate contamination of the groundwater, was predicted by dividing 70% of the dataset as training and 30% as testing data. The R2, RMSE, NSE and PBIAS indexes were applied for model evaluation. The results indicated that the Decision Tree model had the best performance with a large difference compared to the other two models (R2 = 0.957 and RMSE = 0.297, NSE = 0.95 and testing acc = 0.907). After That, logistic regression and artificial neural network had much weaker performances than the lead model. It is suggested to conduct another research with other machine learning models by changing the input variables and add some extra ones such as land-use and compare the results with the current research.

Water, food, and energy are three essential sources for maintaining life and fostering socio-economic development, and they are inseparably interconnected. The aim of the present study was to examine the indicators of water and energy efficiency of major agricultural products, namely, wheat and rapeseed, in two different climates in Sari (temperate and humid) and Sharifabad (hot and semi-arid) plains in Iran. To investigate these indicators in wheat and rapeseed crops, data from the agricultural year 2021-22 were utilized. Initially, the number of samples was determined based on the Cochran formula. Then, sampling was done using a questionnaire designed by the authors. The questionnaires numbered 300, and the collected information included inputs and production quantities. The results showed that the average water physical efficiencies in Sari Plain for wheat and rapeseed crops were 1.13 and 0.67 kg/m3, while in Sharifabad Plain, it was 0.83 and 0.35 kg/m3, respectively. Furthermore, the results indicated that the highest level of input energy in Sari and Sharifabad plains for wheat was 80618 and 71072 MJ/ha, respectively. The results also showed that greenhouse gas emissions were higher in Sari than in Sharifabad, probably because of excessive use of fertilizer and pesticide in Sari. The highest greenhouse gas emissions in Sari for wheat were 2495 kg CO2/ha, and in Sharifabad, it was 2299 kg CO2/ha. Overall, the results indicated that crop performance in humid regions was higher than in dry and semi-dry regions, and this indicator depends on various parameters, including water consumption and agronomic management.

The increase in the human population and the growth in water consumption on one hand, and the rise in sewage production on the other hand, have led to the expansion of environmental pollution threats. The objectives of the present study include launching a pilot project for the localization of knowledge in the design of artificial wetlands in accordance with the quantitative and qualitative conditions of domestic sewage in Iran (specifically, the dormitory of the University of Agricultural Sciences and Natural Resources in Sari) and investigating the possibility of replacing wetland systems with conventional domestic sewage treatment systems in the country.

This study was conducted at the University of Agricultural Sciences and Natural Resources in Sari, involving the construction of six artificial wetlands, each with a length of 3 meters, width of 2 meters, and a height of 1.5 meters, using reinforced concrete. One of the ponds was excluded from the system due to leakage. Inside the ponds, artificial filters at different depths (1 meter: d1 and 1 meter and 30 centimeters: d2) and plant filters (Phragmites australis: p1 and Arundo donax: p2) were filled and planted. D10 and the coefficient of unifo rmity (CU) of the substrate materials were obtained as 2 millimeters and 3.625, respectively, from the grain size analysis. The hydraulic conductivity and porosity of the substrate were 2.523 cm/s and 39.2%, respectively. The specific surface area (SSA) of the substrate materials was calculated as 1.336 m²/kg (2245 m²/m³ of substrate materials). The effluent from the septic tank of the dormitory's baffled septic tank was injected onto the beds after a settling and dilution stage using a pump. In the initial loading, the beds were submerged below the surface, and a three-day retention time was allowed for the first sampling. Quality parameters of the wastewater, including biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), fecal coliform (FC), and total coliform (TC), were monitored to assess the performance of the treatment system.

Although the injected wastewater was diluted up to 25%, a significant removal efficiency of 51 to 55, 41 to 79, 74 to 89, 70 to 95.3, and 78 to 95 percent was achieved for BOD, COD, TSS, FC, and TC, respectively, in different treatments. Among the treatments, the weakest performance was associated with treatment P1D2, while the best purification performance was observed in treatment P2D1. This indicates the dominance of the physical characteristics of the systems at the beginning of the startup period on the purification performance. However, the initial performance of the treatment system was very promising and the removal of some parameters such as TSS and FC was at the average level of a full-fledged wetland treatment system.

This wastewater treatment technology is recommended for all managers and experts in the country's wastewater industry, especially in rural areas with inexpensive land and a population of fewer than 5000 people. These conditions encompass all towns, universities, military barracks, and military facilities as well.

Considering the crisis of water resources and spatial distribution of fertile lands, in order to reduce water consumption and increase food security, it is necessary to use a suitable cultivation model. The purpose of this research is to achieve a suitable cultivation pattern using the method of determining virtual water exchanges in Kurdistan province. The data of this research during the 10-year statistical period (1389 to 1398) in Kurdistan province includes information on the cultivated area and yield of 22 garden crops, irrigation information, meteorological data, population, per capita consumption of food products and their prices, which are calculated in Microsoft Excel ( 2021) has been accepted. The indices related to water requirement values, total virtual water, green virtual water, blue virtual water and virtual water balance were calculated for all selected products. In addition, the lack of attention to the spatial distribution of horticultural crops increased the average virtual water by 26.75 cubic meters per kilogram in Kurdistan province. Virtual water includes 97.4% of the total virtual water for all products investigated in the province, which shows the dependence of the agricultural sector on irrigation in the region. In general, by adopting three indicators of total virtual water, unit value of water and the ratio of required water to available virtual water among the horticultural crops examined, the most suitable cultivation pattern for Kurdistan province in order of priorities is horticultural crops such as seed crops, cold-season crops It is dry, nucleated and grainy. Based on the results of this research, it is suggested to the provincial managers related to the issue that in order to reduce the pressure on the water resources of Kurdistan province and virtual water exchanges, instead of paying attention to the seeded and seeded

In order to investigate the effect of mixing sea and underground water on the morphological and biochemical properties of the purslane medicinal plant, an experiment was conducted in the form of a completely randomized design with three replications in the research greenhouse of Gorgan University of Agricultural Sciences and Natural Resources. The water source treatments included full groundwater (GW100-SW0) as a control, mixing 50% seawater and groundwater (GW50-SW50), half between seawater and groundwater (0.5-GW-SW), and one-half between seawater and Groundwater was (1-GW-SW). The results showed that the use of these water resources at the level of 1% was significant on the fresh and dry weight of root and shoot, height, total chlorophyll, vitamin C and total soluble sugar. Also, these treatments were significant on the amount of chlorophyll a and b, carotenoid and proline at the probability level of 5%. The highest amount of shoot fresh weight, root fresh weight, height and vitamin C were respectively in the control treatment with 61.5 grams, 47.5 grams, 33.2 cm and 74.6 mg per 100 grams of sample fresh weight. The findings show that in most traits, the treatment (0.5-GW-SW) has no significant difference with the control. Therefore, considering the limitation of fresh water sources, the latter treatment is suggested as a suitable source for watering purslane.

Agricultural sector is the largest consumer of fresh water worldwide. Therefore, finding a suitable alternative for the use of fresh water in agriculture can be a key solution to future water crisis issues. Application of saline water by using appropriate methods can be an option for irrigating salt-tolerant plants. One of these methods may be magnetizing irrigation water. In the present study, to investigate the effect of magnetized water on the fresh and dry weight, as well as the essential oil of the medicinal plant Maryam Goli (Salvia L.), a pot experiment was conducted in an open space using a factorial design and completely randomized layout with four replications. The experimental treatments included salinity of irrigation water prepared from different concentrations of Caspian Sea water (30%, 50%, 70%, and 100% mixing with well water) and a control treatment (well water), in both magnetic and non-magnetic conditions. Due to rainfall during the growth season, at the end of the experiment, the saturation extract salinity (EC) of the soil corresponding to the control treatment and the 30%, 50%, 70%, and 100% water mixtures were 3.15 (I0), 3.65 (I1), 4.55 (I2), 4.75 (I3), and 5.06 (I4) dS/m, respectively. The results showed that, in the I4 treatment, both the dry and fresh weights of the plant decreased by 40% and 25%, respectively. However, regarding the effect of magnetized water, the results indicated that in saline treatments with soil EC less than 3.65 dS/m (I0 and I1), use of magnetized water prevented a significant decrease in the weight of Maryam Goli plant shoots. Furthermore, the research results demonstrated non-significant changes in the essential oil of Maryam Goli plant due to irrigation with different salinities as well as magnetic water. Based on the results, it is recommended that irrigation management of Maryam Goli plants using magnetized saline water be carried out in such a way that the saturation extract salinity of the soil does not exceed 3.65 dS/m during the growing season.

The intensification of drought and water stress caused by climate change is a major factor in yield and productivity reduction in the agricultural sector in arid and semi-arid environments. Agricultural lands are often sorely affected by water tension caused by scarce and low precipitation. This research evaluated the effect of different amounts of water, vermicompost and hydrogel used to save the soil water content on wheat grain and biomass yield. Hence, an experiment was conducted at the research farm of Kashmar higher education institute to evaluate the effects of different amounts of hydrogel and vermicompost on wheat biomass and grain yield. Experimental treatments were included: four levels of A200</sub> hydrogel (i.e. 0(S0</sub>), 0.1(S1</sub>), 0.2 (S2</sub>) and 0.3 (S3</sub>) wt. %) plus four levels of vermicompost (0(V0</sub>), 7(V1</sub>), 10(V2</sub>) and 15(V3</sub>) tons per hectare) and three levels of irrigation water (60(W1</sub>), 80(W2</sub>) and 100(W3</sub>) percent of wheat water requirement). The experiment was carried out in a randomized completely block design (RCBD) in a factorial arrangement as a pot experiment in 144 pots. The results showed that the highest amount of biomass and grain yield was obtained in S3</sub>V3</sub>W3</sub> treatment amounting of 81.7 and 35 grams per pot, respectively. Also, the lowest biomass and grain yield was achieved in S0</sub>V0</sub>W1</sub> treatment at the rate of 35 and 10.2 gram per pot, respectively. Furthermore, grain and biomass yield were significantly affected (P ≤ 0.05) by different amounts of hydrogel and vermicompost under varying irrigation water levels. However, application of hydrogel and vermicompost compounds was not significant on the wheat yields. Overall, the best economic value for achieving the highest amount of grain yield was observed in (S2</sub>, 0.2%) of A200</sub> hydrogel and (V2</sub>, 10 ton/ha) of Vermicompost. Similarly, the highest amount of biomass was obtained in the (S3</sub>, 0.3%) treatment of A200</sub> hydrogels and 15 ton/ha (V3</sub>) of vermicompost. Based on the results, the application of moisture absorbents can be effective in increasing wheat yield in water deficit conditions in the arid and semi-arid environment.

The significant reduction of surface water resources and recent recurrent droughts have increased the reliance on groundwater sources, leading to a decline in their quality. In this study, 28 samples of well water from different locations in Khanmirza, Lordegan, Borujen, Ardal and Kiar were collected in 2020-2021 and underwent chemical analysis in the laboratory. To evaluate the quality of the samples for use in agricultural, drinking and industrial sectors, the Wilcox diagram, Schuler diagram and Langlier index were used. Using interpolation methods, the chemical properties of the samples taken within the study area were examined and qualitative zoning maps were prepared using Kriging and inverse distance weighting methods. The results showed that according to the Wilcox diagram, most of the samples are within the range of C2S1 and are suitable for agricultural purposes. According to the Schuler diagram, these samples are within the range of good quality for drinking and based on the Langlier index, they are within the range of precipitating and consumable. This study helps decision-makers to have a clear view and plan comprehensively and effectively for the exploitation and preservation of groundwater resources, taking into account the qualitative maps of groundwater.

The purpose of this research is to analyze the quality of groundwater in Khanmirza, Lordegan, Borujen, Ardal, and Kiar cities based on WQI and GWQI indicators based on the Iran Standard and Industrial Research Institute (ISIRI) and World Health Organization (WHO) standard. In this research, 28 samples of groundwater (wells) were collected from different places in Khanmirza, Lordegan, Borujen, Ardal, and Kiar cities from 2020 to 2022 and 10 qualitative parameters HCO3, K, pH, TDS, EC, Ca, Na, Mg, Cl, and SO4 were chemically analyzed in the laboratory. After analyzing the data, the spatial distribution map of the index was prepared for the study area by using the inverse distance weighting interpolation method. The results showed that according to GWQI and WQI indicators, most of the samples were in the good quality category. By examining the Pearson correlation between WQI and GWQI indices and the parameters used, it was found that the two parameters TDS and EC with coefficients of 0.982 and 0.989 have the highest correlation at a significant level of 1% with the WQI index. Also, TDS and Ca parameters with coefficients of 0.975 and 0.979 have the highest correlation with the GWQI index at a significant level of 1%. The results of this research have shown that the combined use of GIS, WQI, and GWQI indicators in evaluating the quality of groundwater and their spatial distribution in the studied area is useful and effective in selecting water resources for drinking purposes.

Climate change means any specific change in the long-term average weather state that occurs for a given location or for the entire globe (Goudarzi and Koupaei, 2020). Climate change is one of the most critical factors threatening food security, and it is expected to make food and nutrition security more challenging in the future (Carpena et al., 2019). It will affect the agricultural sector by changing the irrigation water requirements, crop yield, and water productivity (Boonwichai et al., 2018; Liu et al., 2019). Rice is the third most important crop in the world, following wheat and maize (Kapela et al., 2020). The occurrence of water shortages and droughts have raised concerns about the sustainability of rice production, including the main rice cultivation production region of Mazandaran in Iran (Yosefian 2018). Most studies have reported that rice production will decrease in the future due to a projected increase in temperature and a projected decrease in precipitation) Basak et al. 2010; Boonwichai et al. 2018; Nasir et al. 2020; Nicolas et al. 2020). Although many farmers, particularly in Iran, feel that permanent flooding conditions for rice farming are inevitable, climate change forces the use of water-saving technologies to ensure the long-term viability of irrigated rice production in paddy fields (Yosefian 2018; Mirfenderski 2022). Accordingly, it is necessary to find new methods for rice cultivation that reduce water use and make optimal use of the available water for irrigation while maintaining yield under climate change. The goal of this study was to examine the water requirement, water productivity, and risk of rice yield for different irrigation levels under various climate change scenarios using a crop simulation model.

Due to the increase in population, food needs, and decreasing fertile agricultural lands without salinity problems, the requirement for irrigation with good quality water will become more valuable every day. In many developing countries, population growth, climate change, lack of land, and improper management of water and soil have caused a decrease in soil fertility and, as a result, limited supply of essential plant nutrients. Considering that Iran is located in the region with hot and dry weather conditions and there are not enough sources of water with good quality in the country and also the soils are mostly salty and calcareous, it is obvious that solutions should be considered to improve the quality of water. Considering the limited water for planting crops, using unconventional waters like salt water, is one of the most suitable ways to increase productivity from agricultural land. One of the methods is the use of magnetic water technology. The purpose of this research is to investigate the effect of using magnetized saline water on the yield and yield components of maize (SC 704) plants by using a drip irrigation system.

The experiment was conducted as a factorial in the form of a randomized complete block design with three replications in the crop year 2021-2022 in Babolsar City with the coordinates of 59 degrees and 39 minutes of latitude (oN) and 36 degrees and 43 minutes of longitude (oE) at an altitude of -21 meters above the surface of the open seas. According to long-term data and based on Dumarten's climate classification, the region has a humid climate. According to long-term statistical data of 30 years, the average annual rainfall of the region is 891 mm and the average annual air temperature is 17.5 degrees Celsius. Irrigation water salinity treatments included 0.6 (S1), 3 (S2), and 6 dS/m (S3) under conditions of application of magnetic field (I1) and without magnetic field (I2). Magnetization of irrigation water was created by passing water through a permanent magnet with a magnetic field intensity of 0.3 Tesla. The working method was that in magnetized water treatments, the device for creating a magnetic field was installed on the pipeline and the water that was considered for irrigation of these treatments passed through this conduit. Irrigation frequency of 3 days and considering the efficiency of 90%, the irrigation demand was determined. Irrigation amounts in each treatment were applied by volume meter. At the end of the experiment period, the characteristics of fresh and dry weight of the plant, number of seeds, weight of 1000 seeds, biological yield and seed yield per lysimeter were measured. SAS software was used for the statistical analysis of the data and comparison of means was done by Duncan's test method.

Salinity stress is one of the factors limiting the vegetative and reproductive growth of most plants and it is a factor that affects the metabolism and morphology of the plant. Due to the lack of quality water suitable for use in the agricultural sector, it is necessary to use non-conventional water. In this research, irrigation with different salinities under the effect of magnetic field on maize yield and yield components was investigated. The results showed that the effect of irrigation type and water salinity on plant wet weight, plant dry weight, number of seeds per cob, 1000 seed weight, biological yield, and grain yield were significant. The comparison results of the average of water salinity treatments showed that there was a significant difference between all the salinity treatments of 0.6, 3 and 6 deci-Siemens/m. Increasing water salinity decreased biomass weight and green cover in maize plants. On average, irrigation with magnetized saline water caused increase of 16.3% in plant wet weight, 21.2% in plant dry weight, 17.2% in number of seeds per cob, 12.9% in 1000 seed weight,13.73% in grain yield and 22.13% increase in the biological yield of maize compared to non-magnetic water. Also, the maize yield components decreased with increasing water salinity. In general, it can be concluded that magnetic water technology can be used to improve plant performance. It is suggested to use magnetic water technology to control salinity in the lands where non-conventional water is continuously used for irrigation, according to the type of plant and the tolerance threshold of the plant to salinity.

Water management in water basins requires information of some facts and full acquaintance of basin conditions, which is problematic due to the deficiency of data collection stations in the country. One of the most suitable methods for flow simulation is the use of hydrological models. In this study, in order to simulate runoff caused by precipitation and to investigate the apparatus of runoff formation and outflow at the outlet of Shahid Rajaei Dam basin located in Sari, the HBV-Light model was used. The purpose of evaluating the stochastic method is to estimate the model parameters and reduce the uncertainty. The length of the daily statistical period was the variables of temperature, precipitation, runoff and evaporation from 1981 to 2015. The Monte Carlo random method was used to estimate the appropriate parameters for the study area. For a consistent assortment, the values of the parameters with a relatively good coefficient of determination were used in the validation section. Finally, the results show the good aptitude of the model in simulating runoff in the study basin. The values of coefficient of determination 0.87, Nash coefficient (NS) equal to 0.66 in the range of good evaluation and RMSE equal to 0.26 in the validation period indicate this issue. In the analysis of uncertainty caused by model parameters, K1, K2 and UZL parameters were identified as the most sensitive in the model reaction subroutine. Therefore, the results showed the importance of accurate determination of water and soil parameters affecting subsurface runoff.

Rivers, as one of the available surface water resources that are exposed to pollutant discharge have extra importance. In this study, while monitoring and simulating the process of qualitative changes in the 8 km reach of Neka River by using the QUAL2Kw, the effects of dams, natural flow waterfalls and bed stabilization structures were evaluated. For this purpose, twice qualitative sampling and local visits were performed. Then, the initial model was prepared and the estimation of data defects, the model was calibrated and validated. evaluation of trend changes in parameters showed that all parameters are within the standard reach and the river has a high self-purification capacity. trending of dissolved oxygen changes showed that the concentration of these parameters was close to saturation, which was due to the favorable hydraulic conditions of the river for aeration rate and the presence of numerous natural and artificial waterfalls in the river. Although the pH value was within an acceptable range, some sections were close to the saturation range because of the release of carbon dioxide due to waterfalls in the flowing water, which the model simulated these effects well. Also, the existence of small dams and creation of a wetland behind these dam Cause to bacteria have been given more time to decompose organic matter, which has increased the alkalinity and pH reach. The results analysis and error indicators showed that the QUAL2Kw model has a good accuracy in simulating the quality of Neka river.

This research was conducted to investigate the effects of using the treated magnetic effluent on chemical properties and heavy metals of soil, water productivity, and uptake of heavy metals by Maize plants. To conduct the research, a factorial experiment was conducted in the form of a randomized complete block design with three replications in two crop seasons (2021 and 2022) in Babolsar City. The treatments included irrigation with well water, irrigation with a mixture of 25% effluent and 75% well water, irrigation with a mixture of 50% effluent and 50% well water, irrigation with a mixture of 75% effluent and 25% well water, and irrigation with 100% effluent in conditions. All these were in the conditions of application of magnetic field and without magnetic field effect. The results showed that the effect of irrigation water and mixing of water and effluent on electrical conductivity, solutes, and heavy metals in the soil at different depths was significant at the probability level of 1%. On average, irrigation with magnetic water decreased electrical conductivity by 33.05%, lead by 37.45%, and cadmium by 65.28%. The results of maize water productivity showed that the effect of irrigation water and water and effluent mixing on biological, physical, wet forage, and dry forage productivity was significant and increased the values of biological, physical, wet forage, and dry forage productivity by 11.51, 10.92, 12.78, and 14.6%, respectively, compared to non-magnetic effluent. By using magnetic water, the concentration of lead, cadmium, zinc, and nickel metals in maize seeds decreased by 19.84%, 19.76%, 15.48%, and 23.01% respectively. The use of magnetic technology enables the optimal use of unusable water and increases the yield and water productivity of plants. Also, this technology can be effective in reducing the accumulation of heavy metals in the soil and maize plants using effluent.

Today, the role of mathematical models in investigating the state of water resources is more prominent than other methods. Therefore, building a mathematical model of the groundwater table and applying management scenarios to it can provide a better view of the future conditions of that aquifer for better management. This research was conducted with the aim of building a conceptual model of the Babol-Amol plain aquifer and investigating the water balance, over-harvesting, the amount of water entering and leaving the study area, and management measures for the sustainability of the current and future situation based on the data of 1985-2021. The results of the water balance investigations of the Babol-Amol alluvial aquifer show that the recharge volume of this aquifer is equal to 312.01 and its discharge volume is 313.41 million cubic meters, which represents the deficit of the volume of the aquifer by 1.4 million cubic meters. It can be seen that the balance of the groundwater table of the Babol-Amol aquifer and accordingly its groundwater level is in relative harmony, but in recent years, on the one hand, due to the increase in the area under rice cultivation in two cropping seasons in the summer, the water level of the aquifer has decreased, and on the other hand, the use of fertilizers and poisons for rice fields has increased significantly. Fertilizers are also drained from the rice fields and seep into the lower layers, and in the rainy season, the rise of the aquifer water level causes the pollution of the groundwater. To prevent these problems from becoming critical, this aquifer needs strategic management in order to maintain the balance of the aquifer and not be polluted in terms of quality, so well drainage in rice fields is one of the solutions recommended for further investigation.