EN
Influence of microrelief and liming on the soil reaction and the microstructure of acid sandy forest soil were investigated. Sampling site was a 40 year old pine plantation on a Cambic Arenosol. The site was characterized by ridge - furrow microrelief. The microstructure of soil samples, taken from two profiles was determined on the base of the mercury intrusion porosimetry measurements. Total porosite, pore volume, bulk density and pore size distribution curves were obtained. Generally, a decrease of the microstuctura) parameters after liming were observed, especially in the ridge samples. Dependence between organic carbon, fulvic to humic acids ratio and total porosity, pore volume, bulk density for lime sample was noted. Solubilization of organic matter, their redistribution within soil profile by leaching and their quantity and quality are the base for explaining the influence of liming on the microstructure of forest soil.