太宽河自然保护区栓皮栎种群动态研究

Study on the Population Dynamics of Quercus variabilis in Takuanhe Nature Reserve

栓皮栎是太宽河自然保护区主要植被建群种之一，研究其种群动态对该保护区生物多样性保护和恢复以及维持生态系统平衡都具有重要意义。通过径级结构分析和树高与直径的生长关系分析，表明该种群为增长种群，树木年龄不超过40年，处于幼龄向中龄发展阶段。静态生命表分析较好地反映出栓皮栎种群生长历史中的消长过程，清楚地透视出20年前坑木择伐对种群动态的长期影响，即径级Ⅴ和Ⅵ（直径8-12 cm）存活株数异常增加、存活率提高、死亡数和死亡率出现负值以及平均期望寿命降低；而相应地对径级Ⅲ 和Ⅳ带来与径级Ⅴ 和Ⅵ相反的作用。该种群的存活曲线符合Deevey Ⅱ 型; 死亡曲线波动异常，反映出强烈的人为干扰影响。建议减少人为干扰，以保护和恢复该区栓皮栎种群。

Quereus variabilis is one of the main vegetation edificators in Takuanhe Nature Reserve. Study on its population dynamics is of great implications for the biodiversity conservation and restoration and ecological system balance maintenance in the area. The research showed the Quereus variabilis population is growing with tree age less than 40 years and in the developing stage from young to middle age by the analysis of diameter level structure and the relationship between tree height and diameter. The increment and decrement processes were indicated from the static life table analysis of the population, clearly showing that the selective cutting as mine poles occurred 20 years ago had a prolonged impact on the population dynamics. The impacts on the diameter levels Ⅴ and Ⅵ were indicated as abnormal increase of survivorship, negative values of mortality and decrease of mean life expectance whereas the impacts on the diameter levels Ⅲ and Ⅳ were opposite to the levels Ⅴ and Ⅵ. The survivorship curve of the Quercus vagabilis population was fit with Deevey Ⅱ. Great influence of human disturbance was also reflected by the abnormal waving of the mortality curve. It is suggested prohibition from human disturbance is necessary to protect and restore the Quercus vaffabilis population.