Effect of silviculture on the nutrient exports along the rotation in tree fast-growing plantation species of northern Spain

Abstract

This paper deals with the evaluation of the amount of nutrients removed and reincorporated after clearcut or thinning in the tree main commercial species of northern Spain: Eucalyptus globulus, Pinus pinaster and Pinus radiata. A simulation of different sylvicultural alternatives was done using stand growth models integrated with control functions which allow to cope with an individual-tree level of detail and a determination of the components of the total aboveground biomass. The high annual rates of extraction in the eucalypts plantations and the adaptation of maritime pine to poor sites where low amounts of nutrients were removed are demonstrated. Heavy thinning sylvicultural regimes give a better nutrient economy for pines. The harvest of no debarked wood is very important for the amount of extractions, particularly in eucalypts.