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Volume XV |

Morphological Analysis of Topolog Basin Fluvial Terraces: A Valleys System Evolution Approach

Abstract: The organisation of valleys network leads to the morphological identity of a territory, developing particular internal developmental models that take into account a number of parameters, such as the climatic, tectonic, eustatic and glacioeustatic ones, the local and regional basic levels or the local morphodynamics. Their highlighting is being reflected in the landscape by structural and quantitative differences resulted from the valley’s evolution up related to each terraces level. In that sense, a probative example is the Topolog’s basin which overlaps three morphostructural units having distinctive dynamics: the Făgăraş Mountains’ Group, the Argeş and Vâlcea Subcarpathians and the Cotmeana Piedmont. The analysis of the position, number, features and structure of the current fluvial terraces, of the way in which the hydrographic network was imposed in the landscape by its evolution enables the identification and tracking of some models with different characteristics on the three sections drained by the Topolog river. Therefore, in the mountain sectorthe valley’s evolution has imposed hydrographic disturbances, in the Subcarpathian one a deepening of the initialcourse and in the piedmont sector some changes through lateral dislocation determined by the amplitude of the elevation process and the thickness of the piedmontan deposits, concurrently with the existence of certain subsidence areas along the Olt river. The direct correlation between the structural features of terraces and the thickness of the deposits along the Topolog river wasaccomplished by an integrated interpretation of the data we have achieved from the electrical resistivity method (49 vertical electrical sounding) and geotechnical survey.

Volume XV |

A complex approach in the interdisciplinary field of karst geomorphology. The case study of Anina karst area (Banat Mountains, Romania)

Abstract: Karst regions are characterized by discontinuity and even by the lack of surface water drainage due to the fissured and porous rocks, but the rivers are often flowing in the underground. Our study area is represented by the Anina karst area, a karst region that is situated in the largest and most compact carbonate area in Romania, the Reșița – Moldova Nouă Synclinorium. This study aims to analyse a mature karst area using a complex approach in karst geomorphology. To achieve this assessment, we intended (i) to get an overall description of the morphology of the area using digital data and GIS methods; (ii) to obtain detailed data regarding cost evolution using geophysics, hydrogeology and speleology, and (iii) to correlate all the data to evaluate the karst terrain from the geomorphology perspective.
Our research is still in progress, and yet we have results that are leading to a complex approach in karst topography research from a geomorphological perspective, using different fields of study as geology, speleology, spontaneous potential as geophysical method and computer science (GIS). Based on our field measurements we were able to correlate those features that are extremely important in karst solution processes, as water circulation, underground conduits, slope, soil properties, water properties in order to have a better understanding regarding the actual landscape in the Anina karst area and also in order to develop hypotheses regarding the possible evolution of karst landforms in the studied territory.
Interdisciplinarity in karst topography studies is very important. Only by involving scientists, and techniques belonging to different scientific domains, we may understand in detail the karst topography. This complex approach is useful for stakeholders and local authorities in their feasibility studies and strategies for local development due to the fact that our study enriches the knowledge regarding karst environment “behaviour” in Anina region.

Volume XV |

Exceptional floods in small basins in North-Western Romania and the induced effects – Bârsău River, Maramureș county

Abstract: The study aims to analyse floods from May 1970, June 1974 and May 2015, which occured in the Bârsău catchment area, one of the right tributaries of the Someș River. The junction between these two rivers is downstream of Satulung locality in Maramureș County. Bârsău catchment area is located between the Someș and Lăpuș catchment areas and has a surface of 152 km2. The floods of the Bârsău River are fast and have a very short propagation time. They are caused both by rainfalls and snow melting. This is the case of the flood from May 1970, which had a duration of two days, whereas the floods from June 1974 and May 2015 occured just because of heavy rainfalls. From the three analyzed floods, the May 2015 flood, with a pluvial origin, reached the maximum level of 220 cm (DL+20 cm) at Buciumi gauging station and its effects strongly affected local people. Thus, the damages in the villages located inside the basin were recorded first, then quantified. After that, there were made the integrating maps of the flood prone areas as well as the hydrological and associated risks in order to identify areas with different degrees of vulnerability.

Volume XV |

Spatial and temporal dynamics of human pressure within the Preajba catchment area, Romania

Abstract: This study refers to the spatio-temporal dynamics of human pressure in Preajba basin, located in the southeastern part of Craiova municipality. The statistic and cartographic analysis is based on the determination of a variety of environmental indices: index of human pressure by demographic dynamics, index of human stress through agricultural land use, naturality index, artificialization index and environmental change index. Choosing a grid of 1.5 sqkm for calculating and comparing the artificialization index of the landscape allows a concise analysis on the environmental transformation in the above-mentioned area. Complementary, temporal dynamics of the environmental indices values is highlighted by the choice of some benchmark years, i.e. 1992, 2002, 2012, 2014 to which data and recent cartographic materials from 2009 and 2014 are added. Results, materialized in the obtained values present the state of the environment and the human pressure implications on the Preajba lacustrine ecosystem (maximum values obtained at period level): physiological or agrarian density – 52 inhabitants/ha in 1992 (Craiova); human pressure index through arable – 1.4 ha/inhabitants in 1992 and 2002 (Malu Mare); naturality index of the landscape – 9.43 in 1992 (Malu Mare); environmental change index – 3.69 in 2012 (Coşoveni). Field campaigns conducted in 2015 and 2016 confirm the research results and visually support human pressure on the environment. The proposed measures, in order to stabilize and maintain the good environmental quality in the Preajba basin targets the lacustrine ecosystem by involving local authorities in order to protect the avi-faunistic natural area status of “Preajba-Făcăi Lacustrine Complex”.

Volume XV |

Evaluation of land use/land cover classification accuracy using multi-resolution remote sensing images

Abstract: Timely and accurate land use/land cover (LULC) information is requisite for sustainable planning and management of natural resources. Remote sensing images are major information sources and they are widely used for mapping and monitoring various land features. Images from various sensors, with different spatial resolutions, are available; however, the selection of appropriate spatial resolution is an essential task to extract desired information from images. This paper presents the conclusions of the work related to LULC classification based on multi-resolution remote sensing images. Optical data collected by three different sensors (LISS IV with 5.8 m and Landsat 8-OLI with 30 m and AWiFS with 56 m spatial resolutions respectively) in 2013 are examined against the potential to correctly classify specific LULC classes. The classifications of images are performed using Maximum Likelihood Classifier (MLC). The results indicate that the overall accuracy and kappa coefficient of LISS IV with 5.8 m are higher than that of Landsat 8-OLI with 30 m and AWiFS with 56 m images. Understanding the role of spatial resolution in LULC classification accuracy will enable the appropriate interpretation of any classified images.