مجله آبخوان و قنات
سال سوم شماره 1 (پیاپی 4، بهار و تابستان 1400)

The water crisis is one of the most important conflicts of the day, and Iran is also in the field of water resources from countries with tension. Following the drop in groundwater levels in aquifers, most of the country's plains have experienced water crisis and water scarcity and their groundwater aquifers have been limited. Among the water stresses, Hashtgerd Plain, which has been selected as the study area. In order to exit the plain from the aforementioned situation, water management should be undertaken with basic management measures, which requires the provision of water resources predictive tools through these measures, one of which is the Bayesian network; In this study, to create a water-borne water prediction model, the predicted variable, groundwater surface parameter in the following month and predictive variables, temperature, precipitation, evaporation, aquifer feeding, The discharge level of the aquifer and the groundwater level were considered in the current month. To reduce information uncertainty, two predictive approaches were used with categorized data (discrete data) and prediction with explicit data (continuous data), and by examining the precision of the pre- The aquifer nose by the two approaches referred to provides explicit precision approach to observational hydrographs. As a result, this approach has been selected as a superior approach for predicting groundwater level due to the application of management scenarios in which the values ​​of the coefficient of explanation 0.94 and the RMSE is 0.207. The approach used in this study can be used in other water resources stresses.

Water, as a major natural resource, is a basic human need and a valuable asset in the absence of which no activity will be sustainable for socio-economic development. In arid areas, groundwater resources are more important and priority given the lack of surface water resources. In addition to the importance of groundwater quantity, its quality is very important and is a direct function of human activities. Groundwater pollution by various types of organic matter and mineral compounds is one of the most common environmental problems today. These pollutants travel with groundwater and will therefore contaminate groundwater resources. Therefore, groundwater pollution is a common threat due to the destruction of groundwater quality and the poisoning of water used by humans. In the present study, MT3D numerical model was used to simulate groundwater quality in Birjand aquifer. Modeling for calcium concentration has been done in 5 years from October 2007 to September 2012. In the calibration step, the error values ​​ME, MAE and RMSE were obtained as 2.147, 6.556 and 9.304 mg / l, respectively. The measured model has been validated using the available information for the next 5 years. The results of the qualitative model showed the appropriate matching of the observational and computational values ​​of calcium concentration.

Evaluation of groundwater quality indices and their zoning has an important role in the optimal management of aquifer. For this purpose, quality indices related to groundwater irrigation of West Azarbayjan province, were evaluated. Related to existing data, quality statistics of 21 wells during2001-2011 were extracted. Pearson correlation index was used to determine the relationship between indices and Wilcox diagram to determine groundwater quality. Kriging geostatistical method was used to study the spatial changes of the indices in the study area. The results of Pearson correlation between the calculated indices showed a significant relationship,at the 95% confidence level, between the values of all indices, except the pH index. Groundwater quality assessment by Wilcox diagram showed that 43% of the studied are located in C3S1 class, 38% of the studied area are located in C2S1 class and 19% of the studied area are located in three classes C3S2, C4S3 and C4S2. Spatial study of all indices showed that the groundwater in the northern and southeastern parts of the province and around Lake Urmia, for agriculture use, is worse than the middle and western parts.

Nowadays؛ climate change and its effects creates a major crisis on the management of water resources. On the other hand؛ since groundwater is one of the most important sources of water supply؛ analyzing the impact of climate change on groundwater in the upcoming period will be necessary. The goal of current study is investigation of the effects of climate change scenarios for the balance of the groundwater level؛ case study on the subterranean water level in the field of Birjand South Khorasan province. In line with this goal in order to evaluate the effects of climate change؛ 26 parameters from the output of the Canadian General Circulation Models (CGCM3.1 AR5) under the emission scenario RCP4.5 was used as predictors. As well as؛ the SDSM model was applied for downscaling the climate data to generate the regional daily scenarios. The Artificial neural Network Fuzzy Integrated System (ANFIS) was used to investigate the changes in the balance of underground water. The results o؛ optimal and intelligent management of groundwater resources and improving the consumption pattern seems necessary.

Changes in temperature and rainfall have a large impact on the quantity and quality of water resources, In this research, the effects of climate change on the development of special Qanats in Khusf city (Giw, Mazhan and Vahad Abad) were investigated. For this purpose, minimum and maximum temperature and precipitation were firstly estimated in the two near future (2030-2060) and far future (2070-2100) using the CANESM2 large scale model and two emission scenarios of RCP4.5 and RCP8.5. These data were then quantified by two downscaling models of LARS-WG and SDSM. Using rainfall data for the upcoming period, Discharge value for 3 Qanats were estimated for future periods. The results showed that the minimum and maximum temperatures in the RCP8.5 scenario would be higher than RCP4.5 in the results of both downscaling methods and will increase for both future periods. Rainfall also has slight variations for two scenarios of RCP8.5 and 4.5 for the upcoming period and the base period. Also, comparing two methods of downscaling, the LARS-WG model estimates the temperature changes less than the SDSM model and less changes in rainfall. The results of Qanat change in the upcoming period also showed that in all qanats, the discharge average for the coming period is less than the base period. Also, the RCP4.5 scenario compared to RCP8.5 in two methods of LARS-WG and SDSM is estimated to be greater. Given the changes in discharge in the future, management strategy can be adopted to deal with possible droughts.

Agricultural activities have grown more due to population growth and increasing demand for more products in the Urmia plain in recent years and have mainly been expanded with groundwater withdrawal, and because of the limited availability of surface water resources, this issue has led to a sharp drop in groundwater resources in the area. In this research, the groundwater footprint indicator was used to study the agricultural products’ effect on groundwater stresses. For this purpose, eight crops were selected, and the indices of water footprints, groundwater footprints, groundwater stresses, water use intensity, and efficiency were calculated. The results showed that the groundwater footprint indicator and the stress on groundwater resources for all studied products in Urmia plain were respectively 464.5 km2 and 5.97 units. Among the studied crops, wheat and alfalfa put the most stress on the groundwater of the region with 1.78 and 2.8 units, respectively. By increasing the irrigation efficiency to 25%, the stress index applied to groundwater for wheat yield became less than 1 unit. The study results on the water use intensity and products’ efficiency also showed that water consumption decreases with increasing efficiency, and products’ efficiency increases. However, increasing irrigation efficiency alone will not eliminate the entire stresses on the agricultural sector, the environment, and in particular, groundwater resources, and it is only an additional factor along with other factors.

Improper quality water use causes problems such as soil salinity and reduced soil permeability. In this study, groundwater quality in Sirjan city has been investigated using common diagrams and parameters in water quality classification for agricultural and industrial uses. Archmap and mini-tab software has been used to graphically display changes in quality parameters in the region and statistical classification of data. The results of the study showed that well (W2) located in the northeast of the aquifer has a higher quality than other sample wells, which is in the range of good to acceptable according to Schuler diagram and in good range according to Wilcox diagram. The amount of magnesium, calcium, sulfate, chlorine and sodium in the well was less than the World Health Organization standard. Also according to the obtained results of well (W12), (W13), (W15), (W17), (W3), (W9) (W10 (W14), (W3) which are located in the northwest, west, south and southwest of the aquifer, both in terms of drinking and agricultural use, of poorer quality than other wells. Enjoys. According to the classified maps, for effective parameters in the Schuler method, the parts of spatial continuity of the data were examined and after preparing the map, locations with different qualities were identified. Also, according to the results obtained from the classification map of the EC parameter by Wilcox method, a large part of the aquifer is in the inappropriate class and only parts of the northeast, east and middle parts of the aquifer are in the middle class.

Nowadays, one of the main problems of water resources in the country is the decline of water resources quality. The increasing demand for water has led to untapped groundwater exploitation and constant water loss in aquifers and as a result environmental problems including the quality of groundwater have been endangered and have created a destructive process. In this study,using the collected data from Neyshabour plain , relationship between groundwater level and increase salinity was determined. In order to investigate the quantity and quality of groundwater in the Neyshabour plain, using the data of surface water level and electrical conductivity, the map of changes in the water level and the qualitative variables were determined in the ArcGIS 10.2 software using a Geostatistics method. The results of the spatial zonation mapping of the quantity and quality of groundwater in wells showed that the water level decreased with the passage of time in the specified period and consequently its amount quality decreased.

Drought and water scarcity in Iran is a climatic reality and due to the increasing need for water in various sectors, the phenomenon of drought will become more severe in the coming years. Therefore, in such conditions, one of the effective and practical solutions is the optimal use and saving of various water uses, especially in the agricultural sector. In this study, by examining the meteorological and soil science information of Imamzadeh Jafar area, the water requirement of crops and orchards was calculated. Then, based on the yield and net income of the dominant crops per hectare, the amount of physical and economic productivity of water in each crop was calculated. Finally, by evaluating the current cropping pattern, the future cropping pattern of the aquifer was proposed. The results showed that the average productivity for the dominant aquifer products was 0.98 kg / m3 and the economic productivity of the products per m3 of water consumption was calculated at an average of 8904 Rials. The results of economic productivity assessment showed that the economic value of the proposed cropping pattern is 7 times higher than the current cropping pattern.

Large number of qanats in Iran and other countries require a systematic naming mechanism. There are thousands of unnamed inactive qanats that are difficult to be addressed and there is no unique method for identification of branches and wells even in well-known qanats. This suggested method is a solution for naming trunks, branches, connections and wells in both old and new generations. In unnamed qanats nomination is based on the use of MRGS geographic position that can be easily searched and located using web based maps. Also, a simple method has been developed for nomination of trunks, branches and connections using 1-3 Latin characters for all of named and unnamed qanats, then the nomination of shafts could be easily done. Naming would be done regardless of being active or inactive for all of the new and old generations of a qanats. This method is tested while mapping qanats using OpenStreetMap.

The main purpose of this study was to calculate the net irrigation requirement of agricultural products in the Qaleh Chay catchment in the current climatic conditions and evaluate it with the data of the National Water Document (NETWAT). For this purpose, the reference evapotranspiration was calculated by the Penman-Monteith-FAO method for the years 2013 to 2019. Subsequently, the plant coefficients were modified according to the guidelines of FAO 56. Then the effective rainfall and net irrigation requirement were calculated. Finally, the net irrigation requirements of the region were compared with the data of the National Water Document. The results showed that the values obtained in this research were in all cases higher than the values mentioned in the National Water Document. This difference was due to the fact that the information used for the calculations in this study was from the year of establishment of the meteorological station of the catchment (2012), while the calculations in the national water document were related to meteorological stations in neighboring cities and years before 1378. Also, increasing temperature and decreasing rainfall in recent years have increased the irrigation requirement compared to previous years. Finally, it is suggested that the estimation of irrigation requirements be done according to meteorological data of recent years to be closer to reality.

Evaporation is considered as a key factor in hydrological, climatic, agricultural water management, irrigation planning, etc. studies. Evaporation is a complex and nonlinear phenomenon due to the interactions of various climatic factors. Therefore, advanced models such as experimental equations and artificial intelligence should be used to estimate evaporation. In recent years, experimental equations have been widely used to estimate evaporation. In this study, the performance of Gaussian process regression (GPR) and support vector machine regression (SVR) models in estimating the daily evaporation of Amol and Bam stations in the period 2020-2016 has been evaluated.Daily meteorological data on mean temperature, relative humidity, sunshine hours and wind speed were used as input of GPR and SVR models to estimate daily evaporation. In the present study, four combined scenarios of meteorological parameters were used to estimate evaporation. The results of the mentioned models showed that both GPR and SVR models have acceptable performance in estimating evaporation (correlation coefficient about 0.94). Also, according to the evaluations, it was found that the GPR model had a better performance than the SVR model (root mean square error of 1.56 and 1.62, respectively). In the present study, the PUK kernel was used due to its high accuracy, highest correlation coefficient and lowest error (0.94 and 0.84).