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Abstract: The UAV technique, and more recently UAS systems, play an ever important role in various domains of research and practical activities. The increase in number of publications focusing on their applicability is spectacular. The objective of this study is to highlight the efficiency of an integrated command-overflight-taking photo system, in an area with obvious problems related to hydric hazards and risks. The quasi-circular shape, the petrography of the upper Ozana basin, its orientation and its opening to the air masses predominantly movement direction, represent just a few of the reasons why it was chosen as the case study. Also, the settlements are displayed on the valleys thread, and this confluence has a remuu potential, in case of isolated rains in the two related subbasins. The UAV Phantom 4 quadcopter, the UAS system, the DroneDeploy application, the UAVPhoto application, the Visual-SFM application, the Daisy algorithm, the micro triangulation network (mesh), the work surface textures, a hyper-resolution of orthophotoplan, DSM model with a 5 cm resolution etc. are the technical elements that made modelling at a very high detail possible. The probability flow rates that were used, were provided by the two hydrometric stations located very close to the study area. Theywere calculated using professional applications approved at the national gauging network level, using the established Krițki-Menkel and Pearson III statistical distributions. The cross-section profiles was performed in the 10.x ArcMap module, using the 3D Analyst extension, and the hydraulic calculation to obtain the average velocity was done using the Manning equation; subsequently, the floodable surfaces was delineated on these profiles. Using the same ESRI module, the flood prone area polygon interpolation and it overlapping over the terrain model and over the orthophotomap were achieved. Paradoxically, the analysis of the results indicates a low degree of the anthropogenic habitat damage, but this aspect is due, in large measure, to the intervention of technical teams in the recalibration of the minor riverbed, massively clogged by alluvial transport.
Abstract: The Habitat Directive (HD) is the main strategy for nature The main aim of the study is to evaluate ground water quality suitable for irrigation purpose in Dindigul Corporation, Tamil Nadu, India. Within the study area 30 water samples were collected to determine the physical and chemical parameters. Sodium Adsorption Ratio (SAR), Sodium percentage (SP), Potential Salinity (PS), Residual Sodium Carbonate (RSC), Kelly’s Ratio and Soluble Sodium Percent (SSP) have been determined to analyze the irrigation water quality. The analysis results reveal that SAR value indicates 84% of excellent, 13% of good and 3% of unsuitable water category. Based on sodium percent, only 10% are good, 50% are permissible and 40% are unsuitable for irrigation. Based on PS and RSC ratio about 97% comes under unsuitable category and 3% are suitable water for irrigation. Kelly’s Ratio and SSP values indicate 27% of good quality and 73% are unsuitable irrigation water. The high concentration of salinity was found in the western part of the study area. The results show that most of the samples are not suitable for irrigation.
Abstract: Drought is a climatic phenomenon induced by a deficiency in moisture due to the decrease in precipitation amount over of a region for a given time period. Thus for evaluating drought, long-time data series are necessary. In the present study on the basis of precipitation amounts registered at Jaisalmer station in Rajasthan state India, meteorological drought indices such as the Standard Index of Annual Precipi-tation (SIAP), Standardized Precipitation Index (SPI), Precipi-tation Anomaly Index (RAI) and Deciles Index (DI) have been computed in order to monitor the drought status. Then Kol-mogorov-Smirnova and Shapiro-Wilk tests were applied to examine the normality of raw data. Sequential Mann–Kendall test (SQ-MK test) was applied for determining trends. The results show no statistically significant trend, but there were points of negative mutation in annual precipitation. Drought monitoring, based on the four mentioned indices, indicate SIAP index as the most appropriate for the study area as its coefficient of correlation is close to 1.
Abstract: On the first hand, the purpose of this article is to present the map and classification of the landscapes of Vitosha Mountain. On the other hand, it aims to present this map as an example and illustration in the context of traditionally applied approaches in Bulgaria in defining the landscape, as well as in researching and classifying the landscapes. There is also a brief overview of the development of land-scape science in Bulgaria.The choice of the territory in study relates to the fact that Vitosha Mountain is a protected area, i.e. a Nature park declared in 1934, now part of the NATURA 2000 network. The Vitosha Landscape Map is developed by using GIS tools and it is implemented as a web-map, which makes it much easier to access, examine and work with it, as com-pared to static maps.
Abstract: The urban expansion of any settlement implies changing natural environment and gradually transforming it into an anthropogenic one to assure the needs of the community. A first step in urban planning is to identify the changes that have been made, and this study reconstructs the anthropogenic changes induced to the Jiu floodplain in the last 150 years, through multi-temporal spatial comparisons, geomorphological characteristics and anthropological and environmental transformation indicators. The processing of historical cartographic materials and current satellite imagery highlights the dynamics of the wetlands and the built-up area in the Jiu floodplain between 1864 and 2017. The urban expansion required flood protection works that were carried out along the canals and lakes resulting from the drainage of the ponds and marshlands. On the course of the Jiu hydro-technical works of straightening, embankment and regularization were achieved, which led to the transformation of the course from a highly meandered one as it was in the second half of the 19th century into a sinuous one in 2017. The study is a useful tool in urban planning, by centralizing the changes in the floodplain, the anthropogenic works carried out and the changes of the Jiu course within the analyzed sector.
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