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Volume IX |

The Ancient City of Callatis and the Neotectonic Movements

Abstract: Southeastwards of Mangalia, 6 – 7 meters under the sea level, on a surface of about two hectares, there were discovered vestiges of the ancient fortress of Callatis. The settlement known since the 4th century B.C. had almost a millenary existence, but it is not known when it ceased to exist and what causes triggered it. Different suppositions were made and, among them, the telluric causes are plausible. The Southern Dobroudja Platform is penetrated by mobile faults and the compartment of Mangalia is affected by a negative neotectonic movement that gets accentuated towards southeast, where the epicentres of earthquakes with repeated manifestation have been observed. The negative movement rate is 3 – 4 mm/year and, cumulated during the 15 centuries that passed since the disappearance of the city of Callatis, it could explain the depth at which the vestiges of the settlement are presently located.

Volume IX |

The Analysis of the Relief Fragmentation Features within the Bălăciţa Piedmont

Abstract: Within the Bălăciţa Piedmont there are to be distinguished two areas with specific features, which correspond to the Danube catchment and to the Jiu drainage area. Both in the case of the drainage density, as well as in that of the relief energy, the distribution of the value classes correlated with the two catchments underlines major differences, but also certain resemblances, situation which is explained by the evolution time, the base level, the flow direction in relation with the structure and the lithological and climatic homogeneity.
The analysis of the data enabled the quantification of the relief energy and of the drainage density within the Bălăciţa Piedmont, as well as the correlation of the two parameters in report to the main catchments. The computation and representation methods for the two indicators of the relief fragmentation (i.e. the depth and the density) allowed for a quantitative interpretation (the identification of five value classes), as well as for a spatial interpretation (the grouping of the values depending on the two collecting rivers: the Danube and the Jiu). The aggregation of the influence factors on the two main drainage areas is mostly due to the fact that the Danube catchment extended its area in the detriment of the Jiu catchment, the three more important tributaries (the Blahniţa, the Drincea and the Desnăţui) catching sectors within the upper course of the tributaries of the Jiu.
The analysis of the relief fragmentation within the Bălăciţa Piedmont shows that this unit is on different evolution stages. The complexity of the fragmentation is closely connected to the maturity degree of the valleys and to the morphogenetic complexes imposed by the paleogeographical evolution.

Volume IX |

The Dynamics of the Present Processes within the Sărăţel Catchment Area

Abstract: The Sărăţel catchment displays a territory mostly located in the molasse area of the Buzău Subcarpathians. The physical-geographical characteristics, as well as the social-human impact, created a complete geomorphologic system, in which the present geomorphologic processes register accentuated dynamics. Starting with the year 2002 until 2008 there were monitored areas with significant impact on the landscape, among the most important processes under study being the landslides, the torrents, the ravines and the creep.

Volume IX |

Endokarstic Relief within the Natural Reserve Area of “Repedea Hill Fossil Site”

Abstract: This study aims to analyze the endokarstic relief of the reserve from Repedea Hill. Although there have been made many geological and geomorphological researches on this sector of the Moldavian Plateau, the endokarstic relief remained largely unexplored until now. The main geomorphological factor in the evolution of this type of relief is the geological substrate from which the lithological component stands out as importance. In the Repedea reserve area the thickness of the lithological association is about 10m and favourable to karstification, composed of oolitic and lumashelic limestone and sandstone. The Repedea oolitic limestone appears as a succession of layers with thicknesses of 2-40 cm separated by intercalations of fine, conchiferous sands of 0.5 – 10 cm. These resistant rock packages have conducted to the forming of a structural karst plateau called the Repedea plateau. The high position of this karst plateau from the whole relief of the studied area can be considered a determining factor for the formation of a suspended authigenic karst with vadose hydrological regime. 9 caves were mapped in the Repedea reserve area and they are located on a relatively small surface of approx. 7 ha. The total length of the mapped underground galleries is of 401 m, thus determining an average density of 5.7 km/sqkm. Unlike the Carpathian caves, in Repedea Hill, the rock type and the local hydrological characteristics do not favour the emergence of massive carbonate concretions because the caves are in a continuous process of caving. In conclusion, the endokarstic relief from “Repedea Hill fossil site” reserve is well developed, strongly differentiating from other endokarstic areas of Romania.

Volume IX |

Assessment of Soil Fertility Management Practices and Their Constraints in Different Geographic Locations of Nepal

Abstract: A farmers’ field survey was conducted in 2009 to evaluate soil fertility management practices and their constraints in certain hill and valley farming systems of Nepal. Thirty households from Okharpouwa village development committee (VDC), Nuwakot and thirty households from Fulbari VDC, Chitwan districts were surveyed using semi-structured questionnaires. In addition, key informants’ interview, checklist survey, observation in the field and documentation of the individual cases were carried out during this research. The study revealed that farm yard manure (FYM) was the major source of nutrients, although the use of poultry manure, goat manure, green manure and chemical fertilizers was also common. We realized that the management of FYM and that of other types of organic manure in the manure pit and in the field was not efficient in conserving nutrients. Similarly, farmers preferred the continuous cultivation of cereal or commercial crops, without mixing the crops or rotating with legumes, the sliced terrace risers in hills, which constrained better production in hills and valleys of Nepal. The specific problems in hills included erosion and leaching of nutrients, soil acidification, while those of valley lands included the imbalanced use of fertilizers, intensive cropping, and crop failure due to improper management.