Geographical studies and environment protection research
Volume X | Issue 1
Downstream Variation in the Pebble Morphometry of the Trotuş River, Eastern Carpathians (Romania)
Abstract: Riverbed sediments morphometrical analysis can offer, along granulometric and petrographic analysis, relevant information on sediment source origin, transport environment and sedimentation process. Today, there are numerous descriptive indices for clasts shape and size, each one trying to evidence the influence of dynamic conditions and clasts petrography that are mobilized in certain transport environment, their shape at certain moments. Among these, this analysis focused on only 10 morphometric indices. The obtained data, either from direct measurements on 5,027 clasts or after index calculations, were processed and obtained a set of statistical parameter (average, median, standard deviation, etc.). Based on these data was assessed „optimal shape” for Trotuş riverbed gravels. Some parameters (like average value) were used to create frequency histograms for some morphometrical indices in sampling points and to make some mathematical modeling.
Volume X | Issue 1
Types of Riverbed along the Lower Course of the Buzău River
Abstract: In the present study there were analyzed two sectors of river bed, located along the lower course of the Buzau River: Vadu Paşii – Săgeata (sector of braided channel) and Ibrianu – Custura. Through the calculation of some indices (the braiding index, the sinuosity index), the performance of correlations between elements established through measurements (length and amplitude of the meanders, the width of the river bed) could be differentiated the types of river beds. By analyzing the Austrian maps in 1910, of the topographic maps, orthophotoplans and Landsat images from 1987, 2000, 2006 and 2007 it could be observed the spatial dynamics of the specific element of each type of river bed. For the Vadu Paşii – Săgeata sector the braiding index reduced from 3.4 in 1981 to 2.32 in 2005. In the Ibrianu –Custura sector, there took place many underpinnings at the level of the complex meanders, and the length of the river reduced from 36.4 km to 24.5 km.
Volume X | Issue 1
Structural and Non-Structural Measures for Flood Risk Mitigation in the Bâsca River Catchment (Romania)
Abstract: The most common natural hazards affecting the Bâsca River Catchment (extended over a surface of 785.1 sq. km in the Curvature Carpathians) are floods and flooding. The purpose of this paper is to investigate and analyze structural and non-structural measures for flood risk mitigating in this catchment. The study focuses on the main factors which generate and favour floods, as well as on flood characteristics (frequency, the largest floods and its consequences). The main methods are the statistical analyze hydrologic and climatic data, field observations, expeditionary mapping and spatial analyses using Geographic Information Systems (GIS).
In order to analyse flood potential, there were processes processed maximum instantaneous monthly and annual discharges of the Bâsca River at the Bâsca Roziliei hydrometric station (1953-2007), Varlaam I (1956-2005), Comandău h.s. (1968-2005) and of the Bâsca Mică River at the Brebu h.s. (1959-1974) and Varlaam II h.s. (1973-2005). Considerations on structural and non-structural measures for protection against floods are presented in the last part of the paper. An inventory of structural works in the middle and lower part of the catchment (hydrotechnical and erosion control works) and their condition was made.
Volume X | Issue 1
Ecological Status Assessment of the Water Bodies Located in the Lower Sectors of the Jiu and the Motru Rivers (Oltenia, Romania)
Abstract: By means of the Water Framework Directive methodology, the present study identifies the valid indicators used for evaluating the ecological status of two natural water bodies (the first located on the Jiu river between Bratovoieşti and the Danube confluence, and the second on the Motru river between the Jirov and the Jiu confluence): hydromorphological indicators, physico-chemical indicators and biological indicators. The quality parameters deviated from the norm are: Shannon-Wiener Diversity Index – 2.87 for the Motru WB and Functional groups index – 0.68 for the Jiu WB (biological Indicators); modified water-cross section coefficient (depth) (1.22) – the Motru WB, impoundment coefficient (0.91) – the Motru WB and Coefficient of major streambed reduction (1.24) – the Jiu WB (hydromorphological indicators). The quality parameters (physico-chemical indicators) of the water drainage systems deviated from the norm are: Biochemical Oxygen demand BOD5 (40.78 mg/l) and Ammonium Nitrogen N-NH4 + (6.96 mg N/l) for Strehaia settlement; Biochemical Oxygen demand BOD5 (33.70 mg/l), Ammonium Nitrogen N-NH4 + (19.66 mg N/l) and Total Phosphorus PT (8.96 mg/l) for Craiova settlement. The target is to validate the ecological status for the two water bodies, respectively „moderate status” for the lower Jiu and „good status” for the lower Motru, related to the Class II and Class III of the European process of intercalibration, ensuring thus the compatibility at European level. The relevance of the paper consists in the assessment of the ecological status of two natural water bodies located downstream with respect to a major punctiform polluting source (two major settlements, Craiova on the Jiu, respectively Strehaia on the Motru), impacting heavily the achievement of environmental objectives set by the Water Frame Directive.
Volume IX | Issue 9
The Determination of the Degree of Trophicity of the Lacustrine Wetlands in the Eastern Carpathians (Romania)
Abstract: The lakes over Romania’s territory are relatively uniformly distributed within most physico-geographical regions. A low density is specific to the West, where significant drainage works have been realized, while the highest density is characteristic to the North-East, with numerous ponds, registered since the 14th-15th centuries. Most of the lakes within the Romanian territory, especially those analyzed in the present study, are anthropic. Most of the natural lakes are small-dimensioned and they do not have a special ecologic or economic importance. Although situated in different physical-geographical conditions, the analyzed lakes are mostly included in the category of good waters from a qualitative point of view, and within the eutrophic, mesotrophic or hipertrophic category, from a trophic point of view. Because of the fact that most lakes are anthropic, it is obvious that they are artificially maintained at this stage. Most of the mountain lakes and those in the volcanic areas are ultra-oligotrophic and oligotrophic. The lacustrine wetlands in the mountainous units are relatively meagrely developed, as their distribution is limited by the morphology of the landforms.