Aliakbar Nazari Samani; mahmoud samadi; arash malekian
Abstract
For developing of water resources a lot of different factors (such as: geological structure, faults, joints and geomorphological metrics) are important. This research tried to assess the effects of geomorphology on karstic water resources in central Elburz region. Geomorphometrics indices were prepared ...
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For developing of water resources a lot of different factors (such as: geological structure, faults, joints and geomorphological metrics) are important. This research tried to assess the effects of geomorphology on karstic water resources in central Elburz region. Geomorphometrics indices were prepared in the form of separate layer in GIS and RS and were overlaid on the springs distribution map. To assess the relationship between springs frequency, discharge and geomorphology statistical analysis such as correlation and factor analysis were done. Results indicate a close relation between spring occurrence and hillslope curvature and TPI. Also the Pearson correlation coefficient of elevation and lineament density and drainage density was significant (P<0.01). According to results the discharge of springs are directly related to drainage density and indirectly related to elevation and lineament density. Moreover the fetor analysis on 17 variables revealed that the first six components had Eigen value of more than 1 and 73.5% of total variance was explained by them. Result indicated that for future developing such a geomorphology characteristics can give suitable information of water resources.
Ali Akbar Nazari Samani; alireza oliaye; sadat feiznia
Abstract
Assessment frequency of springs has become an important issue for land use planning, especially water resource identification and environmental protection.The purpose of this study is to produce a spring occurrence potential map in Bojnourd Basin, based on a logistic regression method using Geographic ...
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Assessment frequency of springs has become an important issue for land use planning, especially water resource identification and environmental protection.The purpose of this study is to produce a spring occurrence potential map in Bojnourd Basin, based on a logistic regression method using Geographic Information System (GIS) and remote sensing (RS). The locations of the springs (359 springs) were determined in the study area. In this study, 14 effective factors including spring were used in the analysis: lineament density, distance to lineament, distance to drainage, drainage density, normalized difference vegetation index (NDVI), profile curvature, tangential curvature, surface rate, vector dispersion, precipitation, elevation, geology, aspect and slope. Binary logistic regression coefficients of the variables by selecting 300 spring randomly. 59 another spring were used for validation that 80.6% of the springs were correctly predicted. The accuracy of the model was measured using ROC curves which showed that accuracy is 86.6 percent which indicates that the model shows high accuracy in the analysis of spring occurrence potential in the study area. The results showed that the distance of lineaments, distance of drainage, drainage density, vegetation index, profile curvature, tangential curvature, vector dispersion, precipitation and slope have the greatest impact on the occurrence of springs. Finally, spring occurrence potential map was divided into four probably classes of very low, low, medium and high. According to the survey results, this method can be used to identify sources of groundwater in karstic zones and has important role in better management of the karstic Basins.
sara Edrisnia; Ahmad Pahlevanroy; Alireza Moghadamnia; Aliakbar Nazarisamani; Abas Miri
Abstract
In Low rainfall, dry areas such as Iran that surface fresh water resources are limited and this water is exposed to pollution risk, finding and preserving underground water supplies is the best way for removing water needs. In addition, in some parts of Iran, climate and tectonic structure have created ...
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In Low rainfall, dry areas such as Iran that surface fresh water resources are limited and this water is exposed to pollution risk, finding and preserving underground water supplies is the best way for removing water needs. In addition, in some parts of Iran, climate and tectonic structure have created good conditions for forming karstic table. Following America, China and Turkey, Iran has the highest percentage of karst and more than eleven percent of Iran’s area is covered by karstic constructors.The purpose of this study is exploring the relationship between lineaments extracted from satellite imageries, tectonic elements, hydrography network and topography factors with Karstic water resources abundance in Maharloo using GIS and remote sensing. Information layers including lineaments, range curvature, elevation classes, slope, vegetation, springs, tectonic elements and hydrography network were provided through field visits, topographic maps, geology, satellite imagery and digital models. Findings were analysed with statistical tests such as Chi square, Pearson correlation coefficient, PCA test, and principal component analysis. It was found out that there is a close tie between formation type, topography (egslope, elevation and range curvature), lineaments and hydrological factors with spring abundance. The significant role of environmental and structural factors drives the necessity of paying attention to them in investigation of the abundance of springs and transmission of groundwater in Karstik areas.
