THE TROPHICITY OF THE LUVISOILS UNDER THE INFLUENCE OF FORESTRY VEGETATION FROM TINCA FOREST DISTRICT, U.P. II SITITELEC, BIHOR COUNTY PUBLISHEDNicu-Cornel SABĂU, P.T. MOŢIU
For the soil quality assessment of qualitative point of view it imposes the characterization of physical, chemical and biological properties of soil corroborates with ecological elements of zonal and local specific. Trophicity it’s an important characteristic of forestry resorts. The trophy potential of non – degraded natural ecosystems can be explained by the potential global trophicity index. The objective of the presented work is to show the influence of forest vegetation, represented by red oak old (Quercus rubra) of 42 year, 77 year old sessile oak (Quercus petraea), and 62 year old oak (Quercus robur) tree on the potential trophicity index of the luvisoils from the area of Tinca Forest District, U.P. II Sititelec. If in the first three horizons the soil is included in silty clay loam sub-class, under red oak and silty loam under sessile oak and oak trees, on the base of profiles, in the Btw2 horizon will pass from the medium clayey loam to the loamy clay both under red oak and oak trees. The estimated values of bulk density are included between 1,30 and 1,33 g/cm 3 in the bioaccumulation horizon A o for all soil profiles and respectively 1,38 and 1,40 g/cm 3 in Btw 2 clay accumulation horizons, the biggest values being registered on stagnic luvosoil profile, under oak trees. The humus quantity in the first horizon of bioaccumulation Ao is higher in case of sessile oak than in case of red oak or oak tree, with 2,53 % and respectively 2,90 %. The corrected potential triphicity index values became of 77.94 under sessile oak and of 65,55 under red oak, on the haplic luvosoils and respectively of 80,03 under oak forest, on luvosol. In spite of the fact that the differences between the values of trophicity index of the three profiles are not essential, the trophicity characterization of these is different. If the characterisation of profile 1 and 2, under sessile oak and red oak (haplic luvosoils) is mesotrophic soil, (T III trophicity class) the characterization of profile 3, under oak forest became eutrophic soil (T IV trophicity class).
trophicity, potential trophicity index, forestry soil, luvisoils