太白红杉种群邻体范围与邻体竞争强度的研究

Study on neighborhood zone and neighborhood competition intensityin Larix chinensis population

采用逐步扩大范围的方法探讨了不同径级基株所受的邻体竞争强度 平均竞争强度和总竞争强度 与影响范围的关系 ,结果发现 : 1 邻体的平均竞争强度随影响范围的增加而降低 ,在一定的范围内下降较快 ,而超出该范围后下降的幅度变小 ,可以此为依据来确定邻体范围 ; 2 不同径级的基株 ,邻体范围有一定的差异 ; 3 邻体总的竞争强度和影响范围的关系服从对数函数关系 CI=Aln C+B .结果表明采用逐步扩大范围的方法能有效地确定邻体范围 。

By using the method of increasing the range gradually,the average and total competition intensity of objective tree was studied.The results show that:(1) The average competition intensity decreases with the increasing of zone,and in a certain zone,it decreases very quickly while it has a little decrease beyond the zone,by which we can ascertain the zone of neighborhood.(2) The plants with different diameter scale have different neighborhood zone.(3) The relationship between the total competition intensity and the interference zone follows closely the following equation:CI=AlnC+B.That suggests the method of increasing the range gradually can provide efficiently the zone of neighborhood.The study provides a new approach to ascertain the neighborhood zone on studying the plant competition.