Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: doubling atmospheric CO concentration on 2 matter distribution and CO exchange of 2 yr growth, dry 2 old sweet chestnut trees (Castanea sativa Mill.). | 506s Ann. Sci. For. 1989 46 suppl. 506s-508s Forest Tree Physiology E. Dreyer et al. eds. Elsevier INRA Effect of doubling atmospheric co concentration on growth dry matter distribution and co2 exchange of 2 yr old sweet chestnut trees Castanea sativa Mill. M. Mousseau1 and . Enoch2 1 Ecologie Végétale Bat. 362 Université Paris-Sud 91405 Orsay Cedex France and 2Department of Agricultural Meteorology Agricultural Research Organisation The Volcani Center Bet Dagan Israel Introduction The amount of co2 in the global atmosphere has increased about 25 during the last century. A doubling of the preindustrial co2 level and an increase of the global surface temperature of at least 2 c is expected in the next century Clark 1982 . The gas exchange and carbon storage capacity of forest trees may play an important role in regulating the global atmospheric co2 concentration. It is therefore important to describe and understand the behavior of tree species with regard to elevated atmospheric co2. Materials and Methods Two yr old sweet chestnut seedlings obtained from a forest nursery were potted in galvanized steel containers 25 cm in diameter 50 cm deep with 24 I of surface soil from a nearby chestnut forest. The plants were sorted according to size 24 matched pairs were made from plants of similar heights and growth patterns. One set of plants was grown in the control growth chamber at ambiant co2 atmospheric concentration 350 ppm the other set at twice that co2 concentration. co2 enrichment was maintained from 15 April to November. The plants were grown in 2 permanently ventilated daylit growth chambers in a field at the University Campus in Orsay France 48 N 2 E . Atmospheric bulk air was blown into the enclosures from air-intakes placed 4 m above the ground. Pure co2 was supplied to the co2-enriched chamber by a steel tank containing 300 kg of compressed co2 Carboxique Frangaise . The growth chambers had a ground area of 2 m2 were 1 m high made out of transparent .
