Infodoc : Sciences, Techniques et Culture

Oak decline, following other instances of forest decline (Picea, Abies, Fagus), has prompted renewed interest in methods that could be used for preventing or remedying a new type of forest decline on soils that seemingly are well buffered. The objective of this research was to ascertain the effect of liming on a soil under an oak-hornbeam forest. The properties investigated were the replacement of H and Al ions by Ca on the soil colloids and the level and activity of soil microbial biomass. The study was conducted in randomized plots at seven levels of finely ground CaCO3, from 0 to 8 Mg ha−1, replicated four times. The results showed that the efficiency of liming after 2 years was about 60%, i.e. that fraction of applied Ca had been converted into exchangeable Ca in the top 10 cm of [...]

Oak decline, following other instances of forest decline (Picea, Abies, Fagus), has prompted renewed interest in methods that could be used for preventing or remedying a new type of forest decline on soils that seemingly are well buffered. The objective of this research was to ascertain the effect of liming on a soil under an oak-hornbeam forest. The properties investigated were the replacement of H and Al ions by Ca on the soil colloids and the level and activity of soil microbial biomass. The study was conducted in randomized plots at seven levels of finely ground CaCO3, from 0 to 8 Mg ha−1, replicated four times. The results showed that the efficiency of liming after 2 years was about 60%, i.e. that fraction of applied Ca had been converted into exchangeable Ca in the top 10 cm of the soil profile. This substitution occurred without significantly decreasing the exchangeable fractions of Mg, K and Na. The effect on soil pH amounted only to 0.16 units Mg−1 CaCO3 ha−1. The response functions were linear up to the maximum dosage applied. This was true for the effect on exchangeable Ca, pH, exchangeable acidity, titratable alkalinity, and base saturation. The effect of CaCO3 on the weight and activity of soil biomass as determined by plate count, partial sterilization and CO2 evolution was negligible with the possible exception of the plate count, where a slight and non-significant effect of liming was observed, irrespective of the amount applied.