ECOLOGICAL ASPECTS OF THE USE OF PEATLAND SOILS - CHANGES OF MICROCLIMATE AND SOIL MEDIUM

The peatland of Borkovicka blata in the Tabor district is a suitable model study site. There are natural reserves, natural therapeutic source, areas after devastation bark deep harvesting, after surface milling cutting, areas cultivated into meadows, forests and reclaimed after harvesting into meadows, forests and arable land. There are also pyrite fen bogs, areas excessively cut and those with properly finished cutting and preserved peatland character. This is an area of occurrence of quality artesian water with spring flowings and artificial wells. During eight years at this site the effect of the use of felled areas reclaimed into forest, for grasslands and arable land on the changes in some meteorological indicators, hydrosphere, physics, chemistry and soil microbiology. The reserve and derelict land served as a comparative area after exploitation of peat. This contribution gives summaries of some results (except monitoring atmosphere). The results show the disturbance of temperature conditions (of air and soil) on areas after industrial exploitation of peat. Maximum and minimum values show an extension of temperature amplitude compared with original situation. Diurnal and nocturnal temperature amplitude extended. From practical standpoint the reduction in minimum ground air temperatures on felled areas in spring and autumn months is significant. In April reduction is 2.55 degrees C, in May 1.66 degrees C, in September 1.62 degrees C and in October 2.40 degrees C. Soil porosity was most stable in the reserve, followed by area after lodging, forest, meadow and arable land. In the reserve maximum capillary water capacity (MKVK) under reduction in minimum water capacity (MVK). On reclaimed areas porosity decreased due to the effect of MKVK and MVK (the most markedly on the arable land). An increase in the reduced value of bulk density weight corresponds to the development of porosity on reclaimed areas where the ash percentage increased as well. The value of soil reaction did not show any significant changes. On arable land C-ox and C-h values decreased, the highest C-f was found in the reserve. The highest quantity of N-t and N-NH4 was in the reserve, the most N-NO3 was on reclaimed areas. P2O5 and K2O contents increased on reclaimed areas, the most and to the greatest depth in arable land. Raised K2O content reaches greater depths (GO cm) compared with P2O5 (30 cm). Vegetation cover, fertilization and intensive management supported the development of biological activity of soil. Decomposition of cellulose increased also basal respiration. Potential respiration shows a lack of easy-available organic substances (increase after alcohol adding). Physiological groups of microarganisms were evaluated as well. Generally speaking, initial values of biological activity of natural peatland sites are low, reclamation activities and they increase by utilization with time. The greatest stability of sire conditions on forest reclamation was manifested in reclaimed areas. Significant changes in arable land take place during reclamation.