Effects of carbon dioxide concentration on assimilate partitioning, photosynthesis and transpiration of Betula pendula Roth. and Picea abies (L.) Karst. seedlings at two temperatures

betula pendula branche branches carbon dioxide crecimiento croissance dioxyde de carbone feuille gas exchange growth growth rate hojas intercambio de gases leaves photosynthese photosynthesis picea abies racine ramas roots stems tallo taux de croissance temperatura temperature tige transpiration