Growth patterns and carbon balance of Pinus radiata and Pseudotsuga menziesii plantations under climate change scenarios in Italy

[摘要] The process-based model HYDRALL has been applied to simulate growth pattems and carbon balance of three Pinus radiata and one Pseudotsuga menziesii plantations growing in different sites in Italy, under current climate and climate change scenarios. In three out of four cases, growth patterns simulated by the model under current climatic conditions showed good convergence with measured growth patterns, as provided by stem analysis. Climatic variables for the period 1990-2100 have been obtained from the General Circulation Model (GCM) projections of the HadCM2 model. At all sites simulations predicted an increase of both temperature and precipitation. The effects of climate change on forest growth was explored by simulating 50-year stand rotations starting from different dates in the 1960-2100 period. Climate change had a positive effect on stand growth patterns, with the largest effect found for P. menziesii (73 and 55% increase for stand volume and height at the age of 40). Mean annual increment (MAI) was also stimulated by climate change, whereas no change in MAI temporal patterns was observed. In three out of four cases the model predicted an increase in the allocation of carbon to the foliage compartment. A positive effect of climate change on net ecosystem exchange (NEE) was observed only for the P. menziesii stand; in contrast, water-use efficiency, estimated as the ratio between net primary production and stand transpiration, increased in all sites. (C) 2004 Elsevier B.V. All rights reserved.

[发布日期] 2004-12-01

[关键词] conifer;forest;drought;carbon;model;HYDRALL