USING GIS IN ASSESSING THE TRENDS IN THE NUMBER OF PEOPLE IN MIDDLE AND UPPER BASIN OF THE RIVER BEGA

The number of inhabitants and their distribution in a given area varies within very large limits of tolerance, both in time and space, regardless of geographic region considered. The natural and anthropogenic frame of the area studied in this paper, namely the upper and middle basin of the river Bega, was described on the basis of existing scientific literature, supplemented by produce maps to work with, such as digital elevation model generated with using Global Mapper software, model used to delimitate the analyzed area; the map of communal territories included in the investigated area was prepared by extracting them from the administrative-territorial map of Timis county, overall population density map and the map of population density developments, compiled from data of population censuses in each communal area, obtained by processing using GIS software. The purpose of this study is to highlight trends in the evolution of the population and to identify areas at risk of depopulation, which means, on the one hand knowledge of the number of inhabitants and for variations in this indicator, on the other hand density analysis population synthetic indicator used to highlight differences in the land surfaces occupied by humans. The upper and middle basin of the river Bega is characterized by a variety of natural and socio-economic conditions, resulting in major differences in the evolution of the number of inhabitants and their spatial distribution. In the period considered (1880 - 2011), the most populous census occurred in 1910, since then a definitely downward trend in this indicator can be observed, until the current period, in some cases "losses " were very large (village Bara, Balinţ, Ohaba Lungă, etc). The downward trend in the number of inhabitants has direct implications on the overall density of the population, over time, this indicator registered a continued reduction in most cases and time periods considered. Estimates on future population numbers are difficult to achieve because some variables can not be predicted or quantified, such as political decisions, migrations and general demographic balance values

FLOOD RISK ASSESSMENT IN RIVER TIMIS BASIN - THE CARANSEBES - LUGOJ SECTOR- USING GIS TECHNIQUE

Flood risk assessment in Timis River basin - the Caransebes -Lugoj sector- using GIS technique. Over time freshets, thus floods constituted and constitute a particularly important issue that requires attention. In many cases, flood damages are extensive to the environment, to the economy and also socially. The purpose of this paper is to identify flood-prone areas between Caransebes and Lugoj, land that is part of the Timis river basin. This paper is based on a theoretical model in which we considered the building elements of the flood produced on the Timis river in April 2005 (levels and flows). to represent the zones flood – prone, we used the numerical model of the terrain, created for the abovementioned area. On this model , according to levels measured at hydrometric stations, were defined those flood prone areas. The Timis river hydrographic basin includes a varied terrain (mountains, hills and plains), with pronounced differences in altitude and massiveness, resulting from tectonic movements that have affected the region, this fact has affected water flow processes, both directly through fragmentation and slope, and indirectly, by creating the vertical climate, vegetation and soils zones. Using GIS technology to study hydrological phenomena and their impact on the geographic area are of particular importance due to the complexity of these techniques, which enables detailed analysis and analytical precision as well as an increased speed of the analysis. Creating theoretical models that give scale to the hydrological phenomena, in this case representing the flood areas, is of great practical importance because based on these models the areas can be defined and viewed, having the possibility of taking measures to prevent environmental effects on the natural and / or anthropogenic environment. In the studied area review of the flood of 2005, were represented flood areas, therefore, according with the researches, several villages, located in Timis valley or in the low lands, where the landscape decreases in altitude, were partially affected, also transport infrastructure (roads and railways) was covered by water in some areas, resulting in the isolation of villages; agricultural land located near or within the localities were flooded, situation that had negative consequences on their productivity. The data presented in this study support the importance and opportunity of using GIS techniques in the evaluation of the hydrological risk assessment, techniques through which tackling the problems that address the geographic area is of a global importance, thus giving clear indications to prevent and protect against destructive phenomena

Ariile naturale protejate din regiunea biogeografică panonică, România

Although it only covers 3% of the territory of the European Union, the Pannonian bioregion is home to a high biodiversity with some endemic species. In Romania, the Pannonian bioregion covers 6% of the national territory, and lies on a strip in the Western part of the country. The main purpose of our study is to evaluate the number, surface and distribution of protected natural areas at the level of Pannonian bioregulation in Romania. According to the data processed by specific GIS methods, before the designation of Natura 2000 sites, the area covered by protected areas was 1.59% (22371.86 ha) in the Pannonian bioregion, and now the area coveredby protected areas has increased up to 13, 92% (217409.01 ha). Of the 79 protected bioreales, 2 have management structures, 26 are managed by the custodians and 51 do not have management or custody facilities, and 25 are under an approved management plan

Assessment of the Impact of Population Reduction on Grasslands with a New “Tool”: A Case Study on the “Mountainous Banat” Area of Romania

The landscapes and, implicitly, the surfaces of secondary grasslands in the mountain areas have been intensively modified and transformed by humans. In this context, this paper analyses the spatial and temporal changes of grassland surfaces following the impact of human population reduction. Thus, the study proposes the implementation of the Grassland Anthropic Impact Index (GAII) as a “measurement tool” to functionally link the two components, grassland surface and human population. The spatiotemporal analyses are based on Corine Land Cover data and demographic data, processed via Geographic Information Systems (GIS) methods and the Land Change Modeler (LCM) tool. The research shows that over a period of 28 years, the population, which was continuously decreasing, caused a series of transformations to the grasslands over an area of 33343 ha. The influence of the reduction in the number of inhabitants was also demonstrated by the direction of the changes produced in the grassland surfaces: in the better populated areas, the grasslands expanded over lands with other uses, and in the sparsely populated areas, they were abandoned. GAII values generally increase with the decrease of the population in the target area, meaning that for an inhabitant (potential user) a greater grassland surface is reported, resulting in a greater responsibility for the management of this resource on a space and time scale. Following the evaluation of the trend of the last 28 years, it was observed that the depopulation of mountain areas can be seen as a threat to grassland ecosystems, either through the transition to other categories of use, or through abandonment. The implications of these phenomena are much broader: they produce chain reactions and affect other components of the regional geosystem