Adia Grozav, Gheorghe Rogobete
The Semenic is situated in the county of Caraş-Severin. Its highest elevation is 1445 m, the crystalline schists are represented of mica-schists, gneiss with granite intrusion. The Semenic has a climate moderately continental, with an annual average temperature, at 1400 m altitude, of 3,5-4,0oC, an annual average precipitation of 1400 mm. the slopes of the Semenic are covered by forests consisting mainly of beech. The high plain consists of pasture with single old beech trees. Because of the numerous springs there are large surfaces with water-logging where the topmost layer contains more or less living Sphagnum patches. The Sphagnum peat below consists of the same moss species and with additional species like Cyperaceae. In those areas were effectuated soil profiles, and the type of soil are Histosols, upon 34 ha, with a total volume of 320000m3. Histosols are Dystric, with o pH of 3,0-4,6, and are composed mainly of organic soil material. During development, the organic matter production exceeds the rate of decomposition. The decomposition is retarded mainly by low temperatures and anaerobic conditions which result in high accumulations of partially decomposed organic matter. Lateral linkages exist with a variety of other Reference Soil Group, including Podzols (Entic, Histi-Entic, Lepti-entic, Haplic, Umbric), Stagnosols, Cambisols and Regosols. A 1,6m Histosols profile was investigated by pollen and plant macrofossil analysis and dates by radiocarbon dating. The bottom date (140-150 cm), 6781±57BP, corresponds to the Mixed Oak Forest – Corylus zone – Middle Atlantic. Around the Histosols. Large areas are occupied by Podzols, soils characterized by the presence of a spodic horizon, in which the pH is 4,77 and BSP is 7,57. In this horizon amorphous compounds have accumulated consisting of organic matter and aluminium, with or without iron or other cations. Management requirements and use possibilities of Histosols are largely conditioned by characteristics such as the low bulk density and high compressibility and the high rate of decay upon drainage (subsidence), liming, fertilization. Podzols are used more often for forestry, extensive grazing or left fallow.
peat; Histosols; Podzols; subsidence; pollen
Presentation: oral