| Different combinations of plant functional traits and trade-offs determine the plant life history strategy,
reflect the adaptation to environmental changes, the variation of functional traits in the individual level reflect energy
investment strategy. In order to understand the changes of leaf functional traits along tree crown, we chose five leaf
functional trait index of two main species (Betula platyphylla and Populus ussuriensis) in broad-leaved /Korean to analyze
the discrepancy. The results indicated that, there was significant correlation between specific leaf area, leaf dry matter
content, unit mass of nitrogen content, unit mass phosphorus content, N/P ratio with tree height in both two species, except
the unit mass of nitrogen content in P. ussuriensis. For layered canopy, there were significant differences of specific leaf
area, leaf dry matter content, unit mass phosphorus content, N/P ratio of B. platyphylla in three layers (upper, middle,
lower), except unit mass of nitrogen content. The leaf of P. ussuriensis grew in the middle and upper canopy, there were
significant differences of specific leaf area, leaf dry matter content, unit mass of nitrogen content, unit mass phosphorus
content in two layers. Changes of leaf functional traits with tree height could be mainly caused by changes of light intensity
in the vertical direction through crown, reflecting the adaptation of plants to light environment, and different resource
allocation way. |
