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One of the world's most pressing needs today is access to groundwater. Although hydrological parameters can generally be estimated using underground studies, these methods are time-consuming and expensive. By taking the direct relationship of these parameters with electrical resistivity and measuring it with a cheaper and faster geoelectric method, a qualitative estimate of these parameters will be obtained. The electrical resistivity method is one of the most widely used methods to probe aquifers. The main objective of this paper is to show how, by interpreting and modeling the data of this exploratory method along with other geological information, the hydrogeological modeling of groundwater reservoirs can be done, and then, with an informed vision, the wells can be drilled for exploitation. For this purpose, the electrical resistivity data at 189 points and 9 profiles in the Shahroud region with Schlumberger array, after reviewing and making some modifications, were subjected to one-dimensional inverse modeling. According to the peripheral vision, the electrode distance was considered to be 50 meters and the length of the profiles is different. The longest profile was 1000 meter and related to profile 3. Then, using the results of modeling along with other available information, the hydrogeological models of the area were prepared in the form of iso-resistivity contour map and interpreted in terms of resistivity and thickness of subsurface layer using computer software Geographic Information System (GIS). Similarly, the thickness map of the aquifer unit (s) was also prepared to classify the good and poor zones. Using the prepared models and also considering the direction and piezometric of the groundwater flow inside the aquifer, suitable places were identified and suggested for future exploitation. [ABSTRACT FROM AUTHOR]

Desertification control is an important issue that must be considered in modern society. In order to effectively improve the accuracy and practicability of the evaluation algorithm of desertification control effect, the Alhagi sparsifolia index under different irrigation amount was taken as the research object, and the evaluation algorithm of desertification control effect was proposed. In the "vegetation-sandstorm-soil" index system, a number of indexes were selected according to the core environmental parameters of Alhagi sparsifolia and grassland desertification. And the analytic hierarchy process, remote sensing, geographic information system, and landscape technology were used to assign index weights of desertification control capacity, which were calculated by multiple discriminant matrices. Finally, the data regression analysis was performed based on remote sensing and computer image information screening and processing to determine the final evaluation results. The experimental data show that the true positive rate of the algorithm in this paper is between 160 and 200, which is within a large range of advantages, indicating that the overall evaluation accuracy of the algorithm is high and the evaluation effect is perfect. [ABSTRACT FROM AUTHOR]

Eco-environmental change prediction models are important decision tools for policy makers, as they help to quantify environmental sensitivity and to understand the relationship between human activities and environmental quality. Thus, this paper aims to analyze eco-environmental changes in Monteiro County, a semi-arid zone within northeastern Brazil between 1987 and 2010, by means of satellite images, geographic information system and global positioning system techniques, topographic map, climatic data and soil maps, as well as field survey. The resulting outputs were evaluated for their ability to accurately predict the most sensitive and least sensitive areas. The results showed that land cover changes have modified the environment in general and the land degradation and low soil loss processes were identified. The mean soil loss decreased from 9.67 t ha-1 yr-1 in 1987 to 2.67 t ha-1 yr-1 in 2010, as an effect of vegetation gain and particularly the conversion of thousands of square kilometers of Tropophile caatinga middle slope and barren land into Tropophile caatinga plain and Tropophile caatinga high strand. Thus, this study provides insight on territorial ordering and management of environmental services with a regional perspective. [ABSTRACT FROM AUTHOR]

Continuously Operating Reference Station (CORS) networks consisting of multiple GNSS systems have been set up and operating in many developed countries. In Turkey, CORS-TR has been operating. The aim of CORS-TR is fast, correct, and reliable collection of all kinds of geographic data, thus, speeding up the activities of cadastre, assuring organized urbanization, constituting the spatial infrastructure for relevant works of e-government, and monitoring plate tectonics. Therefore, in this paper, we investigated 788 days of linear and periodic of AKHR, BEYS, CIHA, KAMN, YUNA, AKSI and KNYA CORS-TR stations by linear trend analysis and Wavelet Transform in located in the Central Anatolia Region of Turkey. As a result of trend analyses of time series it was determined that with the exception of a single station (KAMN), other stations were moving in the Southwest direction (17.78 mm/year). This finding is in consistency with the region's tectonic plate movements. In the periodical analyses, stations' daily, monthly, seasonal, annual and even biennial movements resulting from atmospheric and hydrologic loading, climatic and other effects was revealed. Moreover, Detail (D) component, which protect the largest percentage of energy, was determined by calculating the energy spectrum. Energies of detail components are generally similar in horizontal and especially D7-D8 have the highest energy. However, the components obtained the maximum energy was varied in Up coordinate time series. These results indicate that stations of CORS-TR network located in Central Anatolia were rather stable and able to be providing reliable, accurate and continuous data for national and international studies to be conducted in many fields [ABSTRACT FROM AUTHOR]

The study present the use of Geographic Information System (GIS) to assess the geotectonic regimen of the Sabinas Basin. Initially, the GIS database was designed using geological and geophysical information (total magnetic field reduced to the pole). Subsequently, 2D models of the basin were obtained along 4 profiles running on a north-south direction. The implementation of GIS enables a geological-geophysical interpretation generating various thematic maps that overlap the magnetic map during interpretation. The analysis of overlapping maps enables the identification of areas with different geotectonic regimes in the Sabinas Basin, as well as the relationship between these environments and mineralization. The qualitative and quantitative interpretation of the aeromagnetic data obtained for the total magnetic field reduced to the pole delineate uplifted basement areas as well as shallower blocks within them. This paper presents the location of both the basin's deepest zones and its probable faults, which can be linked to the block boundaries. The faults zones and block boundaries correspond to the main mineral deposits found in the basin. Finally, the geotectonic regime of some sectors of the basin is detailed in order to reaffirm the results obtained by the interpretation of aeromagnetic data. [ABSTRACT FROM AUTHOR]