NIRAJ RIVER’S CHANNEL MIGRATION: A RESPONSE TO HYDRO-CLIMATIC VARIABILITY

Morphometric variables that are specific to Niraj River bear changes along its length due to a series of factors: liquid and solid discharge variation, river slope, the riverbed deposits type, land use changes and engineering works carried out on the riverbed. It can be seen an asymmetric evolution overtime concerning the meanders changing rate in concordance with environmental changes (precipitation quantity, debit, land use). Nevertheless, the lack of annual cartographic materials by comparison with the debit and precipitation data is a barrier in making a direct correspondence between altitude, erosion rate, precipitation and flow. For highlighting the flow variability in time and space of the Niraj catchment we used monthly mean and maximum discharges recordered at Cinta and Gălesti hydrometric stations as well as pluviometric data from stations across studied hydrographic basin between 1970-2009

The Suitability and the Bio-chemical Characteristics of Soils from the Northwest Region of Development from Romania, for Blueberry Crop

We conducted several bio-chemical analyses on soil samples collected from eight blueberry plantations from Northwest Region of Development, using such as Kjeldahl method for total N, Perucci, Krawczyński, Hoffman and Teicher methodology for determine soil enzyme. The bio-chemical analyses conducted provide a better qualitative characterization of soils, providing significant information regarding their fertility degree and favourability for blueberries. For instance, the higher amount of total organic carbon found in four of the eight studied plantation, can be correlated with the same higher amount of enzyme present in soil which have an influence on them, xanthine oxidase and peroxidase activity. Taking into account the requirements needed for a blueberry plantation, we demonstrate that organic soils have also had the highest amount of bio-chemical compounds, such as cambisoil, met in Galații Bistriței, where were also found the highest amounts of different forms of nitrogen (1.755 g/kg total N; 0.0189 g/kg NH4 + and 0.0231g/kg NO3 in Galații Bistriței, comparing to 1.344 g/kg of total nitrogen; 0.0126 g/kg NH4+ and 0.0119 g/kg NO3- in Ulmeni), different forms of carbon and the enzymes that influence this compounds in soil, xanthine oxidase activity, peroxidase activity and nitrate reductase activity

Ecological Influences on Tuber Aestivum Distribution in the Subcarpathian Region of Transylvania

The aim of this research was to identify the ecological factors which have influences on distribution, development and habitat suitability of the summer truffle (Tuber aestivum) in the Sub-Carpathian region of Transylvania. The ecological factors such as average annual temperature (°C), average annual precipitation (mm/year), the length of the bioactive period (months), land slope (grade), slope orientation, soil pH and its compaction level were analyzed having specific influences on forest vegetation development in Sub-Carpathian hills, and in the same time on the possibility of symbiosis existence between the trees and summer truffle. The most favorable regions from the Sub-Carpathians of Transylvania for summer truffle growth proved to be Dealurile Năsăudului and Homoroadelor Sub-Carpathians followed by Muscelele Năsăudului and hills of Bistrița, where the average annual temperature is between 6,8-11°C with an average annual precipitation of 900 mm/year, a 3-6 months long bioactive period and high humus content of the soil

Spatial Analysis GIS Model for Identifying the Risk Induced by Landslides. A Case Study: A.T.U. of Şieu

The risk induced by landslides on residential infrastructure, transport infrastructure and agricultural land causes problems of local management that need to be solved by reducing negative effects and decrease the frequency of their occurrence. This study followed the development and implementation of a model for identifying the risk induced by landslides through the analysis of spatial occurrence probability for landslides at the administrative territorial unit of șieu, following the semi-quantitative method governed in Romania by G.D. no 447/2003 and then through the exposure of housing infrastructure at landslides was possible to frame landslides on risk classes. The entire approach was based on GIS spatial analysis, creating a specific detailed database of causing and triggering factors of landslides and not at least, a database for risk receptors, in this study, represented by the constructions of villages associated with the studied administrative territorial units. The final result of the model highlights the framing of constructions on qualitative risk classes at landslides, revealing the elements of infrastructure that need post and pre event measures of protection

APPLICATION OF SOIL LOSS SCENARIOS USING THE ROMSEM MODEL DEPENDING ON MAXIMUM LAND USE PRETABILITY CLASSES. A CASE STUDY

Application of Soil Loss Scenarios Using the ROMSEM Model Depending on Maximum Land Use Pretability Classes. A Case Study. Practicing a modern agriculture that takes into consideration the favourability conditions and the natural resources of a territory represents one of the main national objectives. Due to the importance of the agricultural land, which prevails among the land use types from the Niraj river basin, as well as the pedological and geomorphological characteristics, different areas where soil erosion is above the accepted thresholds were identified by applying the ROMSEM model. In order to do so, a GIS database was used, regrouping quantitative information regarding soil type, land use, climate and hydrogeology, used as indicators in the model. Estimations for the potential soil erosion have been made on the entire basin as well as on its subbasins. The essential role played by the morphometrical characteristics has also been highlighted (concavity, convexity, slope length etc.). Taking into account the strong agricultural characteristic of the analysed territory, the scoring method was employed for the identification of crop favourability in the case of wheat, barley, corn, sunflower, sugar beet, potato, soy and pea-bean. The results have been used as input data for the C coefficient (crop/vegetation and management factor) in the ROMSEM model that was applied for the present land use conditions, as well as for other four scenarios depicting the land use types with maximum favourability. The theoretical, modelled values of the soil erosion were obtained dependent on land use, while the other variables of the model were kept constant

QUANTITATIVE EVALUATION OF MULTI-VULNERABILITY TO HYDRO-GEOMORFOLOGICAL HAZARDS IN THE UPPER SECTOR OF NIRAJ CATCHMENT

Quantitative Evaluation Of Multi-Vulnerability To Hydro-Geomorfological Hazards In The High Sector Of Niraj Catchment. A study of the natural hazards indicates that floods, landslides, fluvial erosion and soil erosion have the highest spatial-temporal occurrence and lead to the highest material losses in the study area of the Niraj Basin. The present study focuses on the upper section of the Niraj basin, one that still evolving from a hydrological and geomorphological point of view, without any major anthropic interference. Due to its favourability for the establishing of settlements (a consequence of favourable slopes, fertile lands and water resources), the most of the human settlements are situated in the floodplain area, hence in the most flood-prone area during spring and autumn. The rest of the settlements lie on the inferior sectors of the hillslopes, as well as on the valleys of the main tributary rivers of the Niraj, hence being exposed to the reactivated landslides- a consequence of the abundant rainfall events usually leading to floods. A cumulated approach of a multi-vulnerability type has been chosen, one that allows the classifying of the built-up area and roads into spatial classes exposed to the identified natural hazards. Spatial analysis led to the obtaining of quantitative information concerning the number of constructions and the length of roads that can be exposed once the hydro-geomorphological processes have reactivated