Abstract: Nitrogen and phosphorus concentrations, N:P ratio and nutrient resorption efficiency of phyllodes during senescence for Acacia confusa were studied at Wulaofeng, Xiamen.The results showed:(1) Mature phyllodes had the high N concentration, with 39.90±2.10 mg/g in winter, and 43.13±1.67 mg/g in spring;P concentration of mature phyllodes was 1.24±0.04 mg/g in winter, and 1.16±0.05 mg/g in spring, respectively;N and P concentrations decreased with phyllodes senescence.(2) N:P ratio of mature phyllodes was 32.26±1.53 in winter and 37.37±1.61 in spring, respectively;N:P ratios were above 16, which illustrated that Acacia confusa forest was P-limited.Resorption efficiency of P was significantly higher than resorption efficiency of N.

Key words: Acacia confusa, phyllodes, senescence, nitrogen, phosphorus, resorption

摘要： 对厦门五老峰台湾相思成熟和衰老叶状柄的N、P含量、N:P比值及内吸收率的研究表明:(1)台湾相思成熟叶状柄具有高的N含量,冬、春季分别为39.90±2.10 mg/g、43.13±1.67 mg/g,P含量冬、春季分别为1.24±0.04 mg/g、1.16±0.05 mg/g,叶状柄在衰老过程中,N、P含量明显下降;(2)成熟叶状柄的N:P比值冬、春季分别为32.26±1.53、37.37±1.61,均高于16,显示厦门五老峰台湾相思林存在P限制,但叶状柄衰老过程中P的内吸收率显著高于N的内吸收率。

关键词: 台湾相思, 叶状柄, 衰老, 氮, 磷, 内吸收