The interannual and decadal variability and trends of winter (December to February) air temperature over the Oltenia Plain area is analysed for the period 1961 to 2010. The datasets cover monthly temperatures from six meteorological stations. The variability of the temperature data was analysed by means of standard deviation, the mean of three distinct sub-periods (1961-1990, 1971-2000, 1981-2010), as well as the mean of ten-year intervals. Linear regression and the non-parametric Mann-Kendall test were used to emphasize any trends present in the datasets. From the temporal variations viewpoint, an increase in temperature is observed particularly in the third and fourth decades, as the average values for the last decade mark a slight decrease in temperature. From the spatial distribution viewpoint, the most significant positive deviations characterize the northern and western part of the plain. Mann-Kendall test illustrates a monotonic upward trend all over the analysed region, but the results are not statistically significant except for the aforementioned parts of the plain for the entire winter season and February.
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Abstract: In the sedimentary domain, clays represent about half of the detritic rocks in terms of frequency. Clasts with the diameters smaller than 2 or 4μm, according to the used scale, clays, also called pelitic rocks, have to contain as deposits more than 60% clay minerals of the entire petrographic assembly in order to be categorized as clay rocks. Sediments (the primary material) on the base of which they form after the occurrence of diagenetic processes (porosity reduction, cementation of clasts, dissolving of certain minerals and precipitation of others etc.) are known as muds. The type of clay minerals, their morphology, as well as the morphology of the deposits they belong to, the presence and proportion of different chemical elements characteristic to certain well-established depositing environments, gives us clues about the origin of the primary material and about the transformations, it underwent from the initial depositing stage to the moment the sample is taken.
Abstract: The Oltenia Plain represents the western extremity of the Romanian Plain. The analysis of the temperature and precipitation data (1984-2006) proved certain features of the climate in the region, which differentiate this sector of the Romanian Plain from its central and eastern sectors. At the same time, by comparing our results to the data mentioned in previously published studies, it clearly resulted a change of the thermal and pluviometric regime. Thus, the mean annual temperatures registered an increase, exceeding 11°C within the entire region, not only along the Danube Alluvial Plain, while the mean annual amounts of precipitation are characterized by great fluctuations. In the south-eastern extremity of the plain they are below 500 mm, while in the south-west and north they are close to 600 mm. The calculation of the positive and negative deviations, as well as of the moving averages illustrated the climatic instability of the region and an amplification of the duration and severity of the drought periods. Thus, the increase of the temperature was accompanied by a decrease of the precipitation amounts, tendency characterizing almost the entire analysed interval up to the level of 2005, when the huge quantity of rainfall induced lower temperatures and determined a change of both temperature and precipitation tendency. Even if we cannot speak about a desertification process, due to the short analysed period, our results proved the presence of certain climatic changes, which highly influence all the social-economic activities in the area.
Abstract. The present paper aims at defining the concept of modernization of the didactic technology and strategy précising the sense of the two notions, respectively didactic technology and learning technical means. There are exemplified certain models of upper education didactic strategies used in the teaching-learning process with direct reference to Geography. Their purpose is the development of the cognitive interests, of knowledge accessibility, as well as to make the students sensitive, aware, and able to apply them during their pedagogical training and in their future activity in the educational field.