Element Inputs by Litterfall to the Soil in Pine Forest Ecosystems

摘要

Within the framework of the litterfall chemistry subprogram of the integrated monitoring program, litterfall was collected, and the concentrations of Ca, Mg, K, Pb, and Zn were measured during 1999–2003 at the Taurene and Rucava monitoring stations in Latvia. The results showed that at Rucava there was higher production of litterfall than at Taurene due to a higher tree density. The mean annual litterfall was 3630.42 kg/ha~(-1) in Rucava and 3022.11 kg/ha~(-1) in Taurene, with maximum production in autumn at both sites. The litterfall production among the catchments varied seasonally because length of growing period, composition of tree species, and density of snow cover. The higher Ca, Mg, and K concentrations in Taurene were due to greater birch litter contributions and soil chemical properties. The higher Pb and Zn concentrations in the Rucava IM catchment can be explained by the influence of long distance transboundary air pollution and local sources. The chemical element concentrations showed seasonal variation during the study period. The lowest concentration of Ca was observed in spring and the highest in autumn. Concentrations of Mg and K began to increase in the litterfall in spring and then fell dramatically in October and winter. Higher concentrations Zn and Pb were observed in autumn and spring.