STUDY REGARDING THE CARBONATICAL SOILS FROM THE TRANSYLVANIAN DEPRESSION FORMED ON THE EOCINICAL DEPOSITS OF NUMULITS

  • I. Pacurar University of Agricultural Sciences and Veterinary Medicine, Faculty of Agriculture, Cluj-Napoca
  • V. Bunescu University of Agricultural Science and Veterinary Medicine
  • M. Darja University of Agricultural Science and Veterinary Medicine
  • Doina Clapa University of Agricultural Science and Veterinary Medicine
  • L. Holonec University of Agricultural Science and Veterinary Medicine
  • V. Oprea University of Agricultural Science and Veterinary Medicine
Keywords: carbonatical soils, eocen, sarmatian

Abstract

The Căpuşului hills are in the Transilvanian depression a trully ”geologycal eocenic golf” with a rich fossilifeuros fauna (Gryphaea eszerházy, G. gigantica, Turrietella imbricataria, Corbula gallica, Cepatia cepacea, Rotularia spirulaea) and also nummulitus species. The pedogenetic cover is constituted by sedimental deposits (clays, marls, limestones, gritsones). Also the pedogentic cover is represented by preluvisoils, luvisoils, eutricambisoils, clay cernozems. The relief characteristics are the Nummulites perforatus, N. fabianii and N. striatus who are the basically substrates from the acrobatically soils. The Transylvanian Depression is considered to be a true "geological eocenical gulf", is remarked through the conservation of a highly rich fossil fauna. Under the geological aspect, on a crystalline base is revealed the whole series of eocenical formations (striped clays, clays and limestone with "numuliti"), oligocenical (carbonatical clays, sands, sand stones and quaternary deposits) (Posea, 1978; Pop, 2001). These sedimentary deposits lay down from the half of the inferior Miocen and finished during the Panonian's end have constituted the parenthal material for the actual pedogenetical cover. A special characteristic of the landscape (with heights of 600-800m), from the outskirts of the Depression (the Huedin Depression, the Paniceni High hills, the Capus and Savadisla Corridor) is the fact that at the surface coating begin to appear "numulits" (Nummulites perforatus, N. fabianii, N. striatus), close to the localities Capusul mic, Leghia, Savadisla, Aghires, Manastireni, Cluj-Calvaria, Vlaha), deposits on which carbonatical soils are formed. If we view this are from the climate's point of view this area belongs to the Dfbk (Koppen) climatical province. The climate is a temperate continental of high hills, with forest. At Cluj-Napoca the average annual precipitations reach 613mm, the average annual temperature has a value of 8.3 degrees C, and the aridity indicator "De Martonne" has the value of 33.7. According to the climate conditions the studied area belongs to the level of oak (Quercus petraea) and the area of mezofilical oaks. (Quercus robur) Generally the areas of forest are mixed with those of pasture or agricultural crops. Because of the diversity of the ecological conditions the soil cover is extremely different, being constitueted of preluvosoils, luvosoils, eutricambosoils, cernosioms, carbonatical soils. (Blaga 1981, Bunescu &co 2005).