In the highly populated analysed territory, the expansion of the construction zones and the pressure imposed on the slopes by the housing and transport infrastructure led to the appearance and reactivation of mass movement processes that affects the population and the environment. The purpose of this study consist in applying the principles of bivariate statistical analysis in order to determine the dynamic potential of a territory, taking into account the statistical relationship between the independent variables represented by predisposing and triggering factors of landslides (slope, geology, land use etc.) and dependent variables, in this case: landslides. The identification of the degree of validation of the results was determined by calculating the AUROC (Area under the Receiver Operating Characteristic) value, whose value of 0.854 highlights the representativeness of the chosen model. The analysis of landslides susceptibility highlights the inclusion of the territory represented by the hills surrounding Cluj-Napoca metropolitan area, Romania, on the classes of spatial occurrence of these processes.

Identification of Land Suitability for Agricultural Use by Applying Morphometric and Risk Parameters Based on GIS Spatial Analysis

In the case of forests located in the close proximity of urban centres, the functions and conventional roles of the forests have to be largely reconsidered. An experimental study area was located in Făget Forest, near the city of Cluj-Napoca, North-West of Romania, as a subject to evaluate different natural risks, especially landslides. Although most of this area is stabilized, human activity became in the last period the most aggressive and active factor that can induce changes in slopes stability. The evaluation based on new changes on the terrain and constructions has clearly revealed the effect of the unprecedented urban sprawl and the expansion of infrastructure elements and residential buildings. Landslide susceptibility map was elaborated using a multivariate statistical analysis and the Geographical Information System (GIS) technology on a predetermined path inside the forest, as well as obtaining valuable information about the tree species. Based on 14 surveys, each of them covering an area of 500 m2 on a longitudinal transect of the forest, there were identified relatively few tree species with a significant share: Carpinus betulus (42.9%), Fagus sylvatica (24.9%), Quercus petraea (23.2%), Q. robur (6.3%), Prunus avium (1.2%). Their positive roles on avoiding or limiting the flow on slopes, flooding, landslides etc. are different depending on the position, terrain, forest composition, trees density, slope, exposition, but it is fundamental beneficial. However, these species can assure productive (as wood), ameliorative, ecological, landscape, cultural, educational, relaxation roles, and consequently inestimable values.

Floods are natural disasters that cause damage, loss of life, and economic problems throughout the world. Part of these losses can be minimized with the help of different methodologies and tools used to prepare simulations, analyses, and data monitoring to predict such phenomena in time. The metropolitan area of Cluj-Napoca, Romania, is the study area of this paper and it is located in Floresti, the largest rural settlement in Romania. In this area, changes in urbanization, land use, and the expansion of urban areas in a chaotic mode represent a problem. This study focuses on an area prone to flooding due to its proximity to the Somes River. Previous events of this type have caused economic losses that must be considered. This approach combines photogrammetric methods for obtaining data from the field with topographical methods for establishing control points and GIS methods for data processing, modeling, and simulation to obtain the necessary data for flood prevention and intervention.

Currently in Transylvania there are over 600 castles, considered monuments belonging to the world or national heritage. Some of them have disappeared, some are in an advanced degradation, the vast majority being in different stages of degradation, but recoverable, through very expensive investments. The first condition for them to start a program of recovery and put them again in the tourist and cultural circuit is to know exactly the state in which they are, to evaluate the costs. The development of geomatics technologies now allows for the high fidelity assessment of this aspect. These included Global Navigation Satellite System (GNSS) Total Stations + Levels precision, terrestrial and aerial photogrammetry, laser scanners with fixed stations, for each presenting technical data and products analyzed sequentially and corroborated-complementary. The purpose of the entire action was to establish a Workflow as dedicated as possible to the requests of the specialists involved in such projects, architects, builders, restorers, historians, cultural people, etc. The paper can highlight a model of good practices in this field, the researches continuing, by consulting the beneficiaries of products from the range offered through these activities.

The paper presents an application of the methodology used in the paper "Synthetic analysis of geoinformatics technologies for cultural heritage conservation, methodological approach". The creation of the 3D model of the Rakoczi-Banffy Castle in Urmeni., Bistri.a Nasaud County, was done by applying and integrating Terrestrial Laser Scanning (TLS) technologies and aerial photogrammetry performed with an Unmanned Aerial Vehicle (UAV). Agisoft Photoscan was used to compare the results and then they were compared with the images scanned using CloudCompare software. Thus, following the performance, with the help of the mentioned software, of a series of processing of the point cloud obtained, through the two imaging technologies, the error between the points belonging to the point cloud taken with UAV and the one taken with Laser Scanner was between 1 and 15 mm, the margin of error being acceptable for monuments without complex architectural details, so that the point cloud resulting from UAVs can be used successfully in this activity. The aim of the paper is to elaborate a geomatic methodology with an optimized cost-quality ratio, later replicable in the analysis of the current state of other constructions of the same type, knowing that over 600 castles in Transylvania alone are in a similar state, and such cases can be found in other Central European states as well.