秦岭太白山巴山冷杉种内和种间竞争特性的研究

Study on Intraspecific and Interspecific Competition in Abies fargesii on Taibai Mountain

通过对不同方法的比较分析,提出了确定巴山冷杉(Abies fargesii)植株间竞争强度和竞争范围的新方法,并利用改进的方法研究了其种内和种间竞争强度。结果表明:随对象木胸径的增大,由于巴山冷杉种群自然稀疏过程中密度调节作用,植株距离增加,种内竞争强度降低;巴山冷杉主要分布于亚高山地段,群落内太白红杉(Larixchinensis)数量较多,胸径较大,种内与种间竞争关系顺序为:太白红杉-巴山冷杉>巴山冷杉-巴山冷杉>牛皮桦(Betula utilis)-巴山冷杉>其它树种-巴山冷杉;竞争强度和对象木胸径的关系服从幂函数关系(CI=AD-B),当巴山冷杉胸径达到25 cm以上时,种内和种间竞争强度变化较小。研究表明,改进的方法能很好地预测巴山冷杉种内和种间的竞争强度。

The improved competition index and method of qualify the competition zone reflecting objectively the competition and growth pattern of Abies fargesii were selected. The results showed that：with the increase of the size and the distance, the intraspecific competition intensity decreased, because of the population density regulation during self-thinning. In the community, the competition intensity of interspecific was more excessive than that of intraspecific. The order of competition intensity was Larix chinensis- A.fargesii 〉 A. fargesii-A, fargesii 〉 Betula utilis-A, fargesii 〉 other species-A, fargesii. The relationship between competition intensity and individual growth of objective tree followed closely the following equation CI =AD-B ,and the changing of competition intensity was very small when the diameter of the objective tree growed to 25 cm. The improved method could simulate and predict the intraspecific and interspecific competition of A.fargesii efficiently.