tailieunhanh - Báo cáo khoa học: "Relationships between forest tree species, stand production and stand nutrient amount"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Relationships between forest tree species, stand production and stand nutrient amount. | 313 Ann. For. Sci. 57 2000 313-324 INRA EDP Sciences Original article Relationships between forest tree species stand production and stand nutrient amount Laurent Augustoa Jacques Ranger Quentin Ponettea and Maurice Rappb a Institut National de la Recherche Agronomique Centre de Recherches Forestieres de Nancy Équipe Cycles Biogéochimiques 54280 Champenoux France b Centre National de la Recherche Scientifique Route de Mende BP. 5051 34033 Montpellier France Received 22 March 1999 accepted 21 January 2000 Abstract - Data from the literature concerning stand aerial biomass stand nutrient amount . N P K Ca and Mg of four major forest tree species of the temperate area were compiled in order to propose simple general relationships to quantify nutrient depletion associated with biomass harvesting. The objectives was to identify the tree species effect on nutrient loss through biomass removal. Mean weighted nutrient concentrations of aerial biomass decreased rapidly until the maximum current annual increment of stands was reached adult stands the concentration then became more or less constant. For adult stands linear relations existed between aerial biomass and their nutrient amount. Using total aerial biomass TAB or stem biomass including bark SBB as references against the corresponding nutrient amount showed i that correlation coefficients were higher in the latter case ii that nutrient amount per unit of biomass was lower for SBB than for TAB and iii that these relations were species-dependent. For a same SBB species were ranked as follows mean concentration of N and K European beech Douglas fir Norway spruce Scots pine Ca European beech Norway spruce Scots pine Douglas fir Mg European beech Scots pine Norway spruce Douglas fir. For P no significant difference was found for the tested species. The relationships between biomass and nutrient amount can be easily used by foresters to quantify the nutrient amount exported from a site during both .