Leaf area dynamics of Liquidambar styraciflua saplings: responses to nitrogen fertilization
1998
Kuers, K. | Steinbeck, K.
Total leaf production, vertical foliage profiles, and the timing of leaf production and loss were compared in fertilized and unfertilized 3-year-old sweetgum (Liquidambar styraciflua L.) saplings. Nitrogen (N) fertilization increased total leaf area and mass through increased leaf size rather than changes in leaf number or specific leaf mass. Both the vertical and temporal distribution of foliage shifted in response to N. Fertilization increased leaf area primarily in the mid- to upper crown. The midheight of the tree crowns shifted upward throughout the season as leaf abscission occurred from the base to the top of the tree and acropetally along the branches. Peak leaf display occurred in July regardless of N supply. However, fertilized trees had twice the leaf area of the unfertilized trees by early autumn. Leaf area production and loss were modeled separately as a function of fertilization and crown height and the equations combined to model temporal changes in leaf area display.
显示更多 [+] 显示较少 [-]