Groundwater
Sana Maleki; Vahid Nourani; Hessam Najafi
Abstract
Systems for assessing groundwater vulnerability are designed to protect groundwater resources from pollution. The DRASTIC method is a well-known approach for determining groundwater susceptibility. One drawback of the DRASTIC method is that it relies on expert judgment to rank parameters, which introduces ...
Read More
Systems for assessing groundwater vulnerability are designed to protect groundwater resources from pollution. The DRASTIC method is a well-known approach for determining groundwater susceptibility. One drawback of the DRASTIC method is that it relies on expert judgment to rank parameters, which introduces uncertainty. This study used a new generation of Fuzzy Logic (FL), called the Z-number theory, to estimate the specific vulnerability of aquifers and address this uncertainty. The specific vulnerability of the Ardabil and Qorveh-Dehgolan aquifers was estimated using two scenarios: the DRASTIC parameters as inputs and nitrate concentration values as output. The vulnerability of the aquifer was also evaluated by comparing the results of the proposed models with those of the DRASTIC model, which served as a benchmark. The analysis showed that the Z-number Based Modeling (ZBM), which considered data reliability and weighted the rules appropriately, produced higher-quality results than the classic FL. In the Ardabil plain, the ZBM yielded results that were 53% better (using seven inputs) and 184% better (using four inputs) compared to the classic FL. In the Qorveh-Dehgolan Plain (QDP), the ZBM produced results that were 127% better (using seven inputs) and 311% better (using four inputs) than the classic FL. The irregularity and non-linearity of the data, such as the high coefficient of variation (CV) in the Ardabil plain compared to the QDP, may contribute to the high CV value in the plains. Therefore, in plains with high CV, the quality of the extracted Z-number-based rules may be lower.
sayedeh masumeh mousavi; Mohammad Hossein Rezaei Moghaddam; Masumeh rajabi
Abstract
Landslides claim the lives of thousands of people around the world each year, causing enormous damage to people and governments. Landslide risk zoning divides landslides into specific and distinct areas of potential and actual degrees in terms of risk, this process is based on recognizing the qualitative ...
Read More
Landslides claim the lives of thousands of people around the world each year, causing enormous damage to people and governments. Landslide risk zoning divides landslides into specific and distinct areas of potential and actual degrees in terms of risk, this process is based on recognizing the qualitative characteristics of the area and quantitative modeling based on the data of the study area. This can be the basis for long-term planning at the regional and local levels.The purpose of this study is to investigate and zoning landslide risk in the Yellow River Basin located in the east of Khuzestan province using fuzzy logic method; For this purpose, first through field visits, geological maps and topography and by reviewing previous sources and reviewing the conditions of the region; Nine factors: elevation, slope, direction of slope, distance from fault, distance from river, distance from road, precipitation, lithology and land use were considered and selected as effective factors on landslide occurrence. Landslide hazard zoning maps were prepared using fuzzy gamma operator with values of 0.7, 0.8, 0.9. Then, the obtained maps were classified into 5 classes: very high, high, medium, low and very low.The results of the qualitative sum showed that the 0.9 fuzzy gamma operator is more suitable than other fuzzy operators. The results of the classified maps showed that 21.56% of the area in the high-risk zone and 43.24% of the area The area is located in a low risk zone.
hydrogeology
maryam bayatikhatibi; Faeze Rostami; Khalil Valizadeh Kamran
Abstract
In the Drastic model, the vulnerability index was obtained from 57 to 165, which is in the descriptive division into classes without risk to high risk of pollution, which if we consider three classes without risk of pollution to low pollution, we can say 44% of the total area of the plain is located ...
Read More
In the Drastic model, the vulnerability index was obtained from 57 to 165, which is in the descriptive division into classes without risk to high risk of pollution, which if we consider three classes without risk of pollution to low pollution, we can say 44% of the total area of the plain is located on these three classes. Also, three classes of low to high, occupy 46% of the plain area. In fuzzy modeling, after scaling and overlapping seven input layers, we prepared the final map, which according to the index of this modeling, 47% of the total area of the plain has high vulnerability, that the result obtained is very similar to the result of DRASTIC method, but by comparing the two methods, it becomes clear that the fuzzy model is more accurate than the drastic method. In both maps, the northwestern to southwestern parts where the city of Tabriz is located, have the highest potential for pollution and the southwestern parts, which include the Sahand Mountains, have the lowest potential for pollution. Finally, using GQI index and according to drinking standard WHO and using ten parameters: hydraulic conductivity, chlorine, calcium, bicarbonate, magnesium, potassium, total soluble solids, sodium, sulfate and total hardness which are taken from wells in the plain, In high-risk areas, due to the high percentage of total soluble solids, total hardness and high hydraulic conductivity, water quality has also decreased and descriptively, the water quality of Tabriz plain is in the acceptable to appropriate range.
Asad'ollah Hejazi Hejazi; Zahra Zanganeh Tabar; Zahra Zamani
Volume 6, Issue 20 , December 2019, , Pages 121-140
Abstract
1-IntroductionMaterials movement on slope and especially landslides are among the most damaging threats that have been accelerating with human manipulation in natural systems in recent decades (Imami and Ghayumian, 2003). These movements annually cause a lot of financial and psychological damage around ...
Read More
1-IntroductionMaterials movement on slope and especially landslides are among the most damaging threats that have been accelerating with human manipulation in natural systems in recent decades (Imami and Ghayumian, 2003). These movements annually cause a lot of financial and psychological damage around the world in different parts of the country. The rapid population growth, the expansion of cities in mountainous areas, the difficulty of predicting the occurrence of landslide events and the multiple factors affecting this phenomenon reveal the necessity of zoning the risk of landslide. Since prediction of the precise time of mass movements is very difficult, identification of these areas is very important (Mosafaei et al., 2009). Using the zoning of the risk of a landslide event, it is possible to identify vulnerable areas with potential risk, and by providing appropriate management approaches and techniques, to some extent prevent the occurrence of landslides or damage caused by them reduced. Accordingly, the purpose of this study is to identify areas susceptible to landslide in the Sarpolzahab Basin. The Sarpolzahab Basin is one of the mountainous regions of the western part of the country which is prone to various types of slopes due to special geomorphological conditions. In this research, for the potential estimation of areas susceptible to landslide, two models of WLC and OWA for zoning and an analysis of the network (AHP) model for weighting into layers have been used.2-MethodologyThe research methodology is based on software, library and analytical methods. In this research, eight layers of information were used to identify landslide susceptibility. Information layers include: 1 elevation, 2 slopes, 3 slopes, 4 rivers, 5 faults, 6 lithology, 7 communication paths and 8 land use areas. The general trend of the present research is that in order to identify the susceptible landslides, information layers were first provided (the choice of information layers was based on the purpose of the research and according to the experts' opinion), and then these layers were based on the opinion of the experts (5 geomorphologist) and using the network analysis model (AHP). After weighing the information layers, the weight is applied to each of the layers, and then, in order to combine and combine the information layers, three methods of fuzzy logic, WLC and OWA have been used.3- ResultsIn this research, in order to achieve the desired goals, information layers are first provided. After providing information layers to combine information layers, layers are standardized using fuzzy area. Layer standardization is based on expert opinion and research objectives. For layers of elevation and gradient, gradient and high-lying areas of value near 1 and low-gradient and low-lying areas are considered to be close to zero. For layers of slope directions, the northern directions are worth close to 1 and the southern directions are close to zero. Also, areas near the lines of the fault, the river and the communication path are worth close to 1 and the distant areas are close to zero. For the land use, the uncovered areas are close to 1, and areas with dense vegetation are close to zero. For the lithology layer, areas with low resistance to lithology such as marl, lime and alluvium have a value of close to 1, and areas with more resilient lithology (basalt areas) are close to zero. 4- Discussion and conclusionThe results of this study indicate that the studied basin has high potential for slippery slopes movement. In fact, the existence of hurdles and the availability of other parameters have led to a relatively large and large part of the eastern basin. Comparison of potentiometric methods suggests that in all three methods, the eastern regions have the highest and western regions with the least potential for landslide occurrence. In the fuzzy logic method, the potential class has the highest potential of 195 km2, and the average potential class with the 121 km2 has the smallest extent, which mainly includes the western regions and the outlet of the basin. In the OWA method, the relatively large potential floor area has a maximum area of 210 square kilometers, which mainly includes the central and eastern heights of the basin. In this method, the high potentiality class with the area of 116 km has the lowest status, and mostly you are the northern and central areas of the basin. In the WLC method, the relatively high potential class with 180 and a high potential floor area of 120 km2 has the highest and the smallest extent.
Ata Allah Nadiri; Saeed Yousefzadeh
Volume 4, Issue 10 , June 2017, , Pages 21-40
Abstract
An accurate estimation of the hydrogeological parameters such as hydraulic conductivity, which is essential for careful management and protection of groundwater resources, is an important part of hydrogeological studies. Various field and laboratory methods, generally done using hydrogeological data, ...
Read More
An accurate estimation of the hydrogeological parameters such as hydraulic conductivity, which is essential for careful management and protection of groundwater resources, is an important part of hydrogeological studies. Various field and laboratory methods, generally done using hydrogeological data, have already been proposed for estimating hydraulic conductivity. One of the best and the most complete methods is the field pumping test which is very time-consuming and expensive. In addition, hydrogeological parameters estimated by it have an inherent uncertainty. In this study, we tried to use artificial intelligence methods, widely considered in recent years, such as artificial neural network (ANN), mamdani fuzzy logic(MFL), sugeno fuzzy logic(SFL), and adoptive neuro-fuzzy inference system (ANFIS) for the estimation of the hydraulic conductivity. In this study, for the accurate estimation of the hydraulic conductivity in Maraghe-Bonab plain by these models, geophysical and hydrogeological data were used as models' inputs. Their results were compared with the evaluation criteria, and the best model based on the RMSE was selected. Accordingly, the ANFIS model, compared to other models, with an RMSE of 1.12 in the test phase has high power in the estimation of the hydraulic conductivity. Radius of clustering, number of fuzzy rules, and number of clusters are very important in fuzzy and neuro-fuzzy models. Radius of clustering in the ANFIS model, based on the minimum RMSE amount, was equal to 0.4 and the numbers of clusters, based on if-then fuzzy rules, was 9. The methods presented in this study, which demonstrated superior performance in estimating hydraulic conductivity of Maragheh-Bonab plain, can be used in estimating hydraulic conductivity of other plains with similar hydrogeological conditions.
Sorayya Abbasi; Masoud Heydari
Volume 3, Issue 6 , January 2017, , Pages 75-93
Abstract
Sorayya Abbasi[1] Masoud Heydari[2] Abstract One of the important issues in water resources management is the identification of ground water behavior. The aim of this paper is the estimation and comparison of two methods for potential ground water, sites by the use of Analytical Hierarchy Process (AHP) ...
Read More
Sorayya Abbasi[1] Masoud Heydari[2] Abstract One of the important issues in water resources management is the identification of ground water behavior. The aim of this paper is the estimation and comparison of two methods for potential ground water, sites by the use of Analytical Hierarchy Process (AHP) and fuzzy logic. In order to achieve this objective 8 parameters including lithology, rivers, slpe changes, land use, topography, population, springs, wells, faults and fractures were used as information layer in the northern part of Ilam provicne with an area of 5218 km2. The final map obtained by AHP shows that high groundwater recarge potential exists in the limestone areas with high fractures. The evaluation of different overlap models, according to the level of compliance with the lithology indicates that fuzzy integrated method (algebraic sum) is mor appropriates than other methods in finding groundwater potential sites of reservoirs in the area. The method using 1000 km2 scope proves high potentials in the central parts of the map, which shows an acceptable consistence with the final map obtained by analytic hierarchy process while consistency of the related maps of springs and wells map in the region also confirm accuracy of these methods. [1]- Ph.D. Candidate of Geology, Faculty of Sciences,University of Birjand, Iran, Emil:s.abbasi1363@yahoo.com. [2]- Master Student Candidate of Geology, Faculty of Sciences,University of Birjand, Iran.
