Litter fluxes and decomposition in Nothofagus pumilio stands in the region of Magallanes, Chile

Seasonal and annual litter fluxes. potential nutrient returns, and litter decomposition were evaluated in two stands, one natural stand and the other under a shelterwood system, within a natural Nothofagus pumilio forest located in the region of Magallanes, Chile. Fluxes were determined by means of 24 collectors installed in each stand. Decomposition was evaluated from the periodical record of the weight losses undergone by decomposition bags extracted from the floor of the stands. Mineral nutrient average concentrations and masses of seasonal litter contributions were determined. Annual litter flux was 2.0 t ha(-1) in the natural stand and 1.0 t ha(-1) in that under a shelterwood system. In both cases, the highest contributions occurred in the fall (49-51%), with leaves being the component with the highest rate, both seasonally and annually. According to weight losses, annual decomposition reached 35.8 and 53.0% in the natural stand and that under a shelterwood system, respectively. Average decomposition rates for the evaluated periods were 0.38 and 0.50, while rates at the end of the evaluation year were 0.44 and 0.76. In both estimations, the highest rates corresponded to the intervened stand. Results showed that forestry intervention significantly affects seasonal and annual contributions of organic residues, potential nutrient returns, and initial litter decomposition rates. (C) 2001 Elsevier Science B.V. All rights reserved.