Kloeppel B D, Abrams M D
Institute of Ecology, University of Georgia, Coweeta Hydrologic Laboratory, 3160 Coweeta Laboratory Road, Otto, NC 28763, USA.
Tree Physiol. 1995 Nov;15(11):739-46. doi: 10.1093/treephys/15.11.739.
When the exotic Acer platanoides L. (Norway maple) and the native A. saccharum Marsh. (sugar maple) grow together in the understories of urban Quercus forests in the eastern USA, average annual height growth increments are nearly twice as large in A. platanoides as in A. saccharum, 19.26 +/- 3.22 versus 10.01 +/- 1.69 cm. We examined several ecophysiological mechanisms that might be associated with the superior invasive ability and growth of A. platanoides in two urban oak forests in Pennsylvania. Leaf longevity was 12 days greater in A. platanoides than in A. saccharum. In addition, leaf mass/leaf area ratio was greater in A. platanoides than in A. saccharum (2.67 +/- 0.03 versus 2.32 +/- 0.02 mg cm(-2)); however, leaf thickness was significantly lower in A. platanoides than in A. saccharum suggesting that A. platanoides contains more dense palisade and mesophyll cell layers than A. saccharum. Field net photosynthesis (mass basis) and photosynthetic light response curves (area basis) indicated significantly greater carbon assimilation, and nitrogen and phosphorus use efficiencies in A. platanoides than in A. saccharum. Acer platanoides also exhibited higher water use efficiency than A. saccharum (0.88 +/- 0.12 versus 0.32 +/- 0.09 mmol CO(2) mol(-1) H(2)O). Acer platanoides exhibited significantly lower osmotic potentials than A. saccharum, but a similar relative water content at zero turgor. We conclude that A. platanoides utilizes light, water and nutrients more efficiently than A. saccharum.
当外来物种挪威槭（Acer platanoides L.）和本土物种糖枫（A. saccharum Marsh.）在美国东部城市栎树林的林下共同生长时，挪威槭的年均树高生长增量几乎是糖枫的两倍，分别为19.26±3.22厘米和10.01±1.69厘米。我们在宾夕法尼亚州的两片城市橡树林中研究了几种可能与挪威槭更强的入侵能力和生长状况相关的生态生理机制。挪威槭的叶片寿命比糖枫长12天。此外，挪威槭的叶质量/叶面积比大于糖枫（2.67±0.03对2.32±0.02毫克/平方厘米）；然而，挪威槭的叶片厚度显著低于糖枫，这表明挪威槭比糖枫含有更密集的栅栏组织和叶肉细胞层。田间净光合速率（基于质量）和光合光响应曲线（基于面积）表明，挪威槭的碳同化、氮和磷利用效率显著高于糖枫。挪威槭的水分利用效率也高于糖枫（0.88±0.12对0.32±0.09毫摩尔二氧化碳/摩尔水）。挪威槭的渗透势显著低于糖枫，但在零膨压下相对含水量相似。我们得出结论，挪威槭比糖枫更有效地利用光、水和养分。
