Components of leaf dry mass per area - thickness and density - alter leaf photosynthetic capacity in reverse directions in woody plants
Components of leaf dry mass per area - thickness and density - alter leaf photosynthetic capacity in reverse directions in woody plants
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DOI：
10.1046/j.1469-8137.1999.00466.x
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发表时间：
1999-10-01
期刊：
影响因子：
9.4
通讯作者：
Niinemets, U
中科院分区：
文献类型：
--
作者：
Niinemets, U
单位面积叶片同化能力(P-max(P))与单位面积叶片干质量(LMA)和单位面积含氮量(N-P)的关系因种而异，不同生境种内的关系也不同。为了更好地了解P-max(P)对LMA和N-P的依赖关系，本文基于597种木本植物的地球生物群，研究了叶片光合作用能力与LMA组成(叶密度(D，单位体积干重)和厚度(T))的关系，以及D和T与不同组织中叶片氮含量和叶体积分数的关系。在所有物种中，P-max(P)变化12倍，单位干物质的光合作用能力(P-max(M))变化16倍，N-P变化12倍，单位干质量氮(N-m)变化13倍，LMA变化16倍，D变化13倍，T变化35倍，表明叶片形态比叶化学和同化速率更具可塑性。尽管P-max(P)与N-P、P-max(M)与N-m呈极显著正相关，但叶片结构是决定叶片同化能力的更重要因素。P-max(P)随LMA和T的增加而增加，但与D无关，而P-max(M)与LMA呈负相关，与D呈负相关，与T的相关性较差。对叶片氮素和组织组成数据的分析表明，D与P-max(M)的负相关是由于D与N-m、D与叶内空气体积分数、D与共质叶分数的负相关。因此，叶片密度的增加导致(1)同化叶片化合物的减少，以及(2)叶片解剖结构的广泛改变，这可能导致细胞间对CO的转移阻力增加。总而言之，(1)和(2)导致P-max(M)降低，并且还修正了P-max(P)与LMA的关系。
The relationships of foliage assimilation capacity per unit area (P-max(P)) with leaf dry mass per unit area (LMA) and nitrogen content per unit area (N-P) differ between species and within species grown in different habitats. To gain a more mechanistic insight into the dependencies of P-max(p) on LMA and N-P, this literature study based on 597 species from a wide range of earth biomes with woody vegetation examines the relations between leaf photosynthetic capacity and the components of LMA (leaf density (D, dry mass per volume) and thickness (T)), and also the correlations of D and T with leaf nitrogen content and fractional leaf volumes in different tissues. Across all species, P-max(P) varied 12-fold and photosynthetic capacity per unit dry mass (P-max(m)) 16-fold, N-P 12-fold, and nitrogen per unit dry mass (N-m) 13-fold, LMA 16-fold, D 13-fold, and T 35-fold, indicating that foliar morphology was more plastic than foliar chemistry and assimilation rates. Although there were strong positive correlations between P-max(P) and N-P, and between P-max(m) and N-m, leaf structure was a more important determinant of leaf assimilation capacities. P-max(P) increased with increasing LMA and T, but was independent of D. By contrast, P-max(m) scaled negatively with LMA because of a negative correlation between P-max(m) and D, and was poorly related to T. Analysis of leaf nitrogen and tissue composition data indicated that the negative relationship between D and P-max(m) resulted from negative correlations between D and N-m, D and volumetric fraction of leaf internal air space, and D and symplasmic leaf fraction. Thus, increases in leaf density bring about (1) decreases in assimilative leaf compounds, and (2) extensive modifications in leaf anatomy that may result in increases in intercellular transfer resistance to CO,. Collectively, (1) and (2) lead to decreased P-max(m), and also modify P-max(p) versus LMA relationships.