Effects of stem size on stem respiration and its flux components in yellow-poplar (Liriodendron tulipifera L.) trees.

摘要: Carbon dioxide (CO2) released from respiring cells in the stems of trees (RS) can diffuse radially to atmosphere (EA) or dissolve xylem sap and move internally tree (FT). Previous studies have observed that EA decreases as stem branch diameter increases, but cause this relationship has not been determined, nor confirmed between RS, which includes both FT. In study, for first time mass balance technique was used estimate RS Liriodendron tulipifera L. different diameters, ranging 16 60 cm, growing on same site. The magnitude component fluxes scaled with size. Among five trees, contribution decreased linearly increasing sapwood area while FT increased area. For smallest 86% it only 46% largest tree. As size a greater proportion respired CO2 dissolved remained within Due increase size, we sizes had even though they EA. This appears explain why branches their increases.