台湾相思叶状柄衰老过程中氮磷内吸收变化研究

Resorption Efficiencies of Nitrogen and Phosphorus of Phyllodes during Senescence for Acacia confusa at Wulaofeng, Xiamen

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。

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： （l）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.