How much carbon do Argentine Pampas Pinus radiata plantations store?

Abstract

Aim of study: To quantify the biomass and carbon stored in the main ecosystem components in Pinus radiata D. Don plantations across an age sequence in the Pampean region of Argentina. Area of study: Plantations were established on non-agricultural land, southeast of the province of Buenos Aires. Materials and methods: Fourteen sites were selected of Pinus radiata plantations, 9-, 13-, 15-, 19- and 21-years-old, in a first forest rotation. Forty-two trees were destructively sampled, allometric functions were set and biomass was estimated for the different compartments (needles, branches, stem). Root biomass was estimated from equations adjusted by the sampling of twenty-four trees. At 4 sites, C-stock was determined in the tree component, in the forest floor and understory, and soil organic carbon (SOC) was determined to a 50 cm depth. Main results: C-stock in the tree component increased with stand age, whereas SOC and C-stock in the forest floor and understory were not related to stand age. The system-level C-stock was 273.1, 263.7, 269.7 and 324.1 Mg ha-1 for the 9-, 13-, 19- and 21-year-old stands. On average, 69% of the total system-level C-stock was in the soil, while 28% was in the tree biomass and 3% was in the forest floor and understory.