Nutrient changes in decomposing beech leaf litter assessed using a solution flux approach

The decomposition of beech (Fagus sylvatiea L.) leaf litter was examined in lysimeters. The experiment allowed comparison of data from mass changes of bioelements in leaf litter and the solution flux balance of through fall input and lysimeter output over a two-year period (1983 and 1984). The annual C loss from the leaf litter was 19%. Na and K concentrations in this leaf litter decreased in the first year and remained constant in the second, while those of Ca and Mg showed no significant changes. N and S amounts per ha increased during the first year by about 7 kg N ha^?1 and 0.5 kg S ha^?1. Ash, Fe, Mn and Al amounts per ha increased to 470, 130 and 240% of their initial levels. These net increases in the first year of decomposition are discussed. The mean annual water and element input by through fall during the experiment corresponded approximately to the long-term average. Thirty to 40 mm more water was evaporated from the litter layer in the drier year (1983) than in 1984. Total N, NO, Na and C1 flux rates of through fall inputs and lysimeter outputs were equal. NH, input rates were greater and organic N smaller than the output rates of the lysimeters. Water balance data indicated that the lysimeter output of K, Mg, Ca and SO, exceeded through fall input. Probable reasons for these differences are discussed.