重庆四面山采伐迹地杉檫人工混交林干扰效应

The neighborhood interference effect in Cunninghamia & Sassafras mixed artificial forest on cut-ovr land in Simian Mt. Chongqing

研究了重庆四面山杉木（Cunninghamialanceolata）与檫木（Sassafrastsumu）人工混交杯中，单对杉、檫之间的邻体干扰效应．用张跃西改进的邻体干扰模型，以杉木为基株，檫木为唯一邻体，研究了杉、檫个体大小、生长速度、邻体干扰效应之间的关系．与纯林中的杉、檫相比较，并倒推7年以来邻体干扰指数的变化,结果表明，杉木受到了更大的干扰，且干扰随种群年龄的增长有不断加强的趋势（p＜0．01）．并指出根据其趋势的增长变化程度，应进行适时间伐。

The neighborhood interference effect of single Cunninghamia-Sasafras pair in Cunninghamia & Sassafras mixed artificial forest in Simian Mountain, Chongqing, is focusedon. Regarding cunninghamia as object model modified by Zhang Yaoxi, the relationship between individual size, prowth rate of Cunninghamia and Sassafras and neighborhood interference effect are studied. Moreover, they are compared with those of Cunninghamia & Sassofras in single-species froest, and the variation of neighborhood interference index is deduced from now to seven years before. The research shows that Cunninghanmia individuals have been interfered by Sasafras individuals much more than Sassafras individuals interfered by Cunninghamia, and the interference that Cunninghamia suffered tended to inerease with population age. The relation of Cunninghamia population age to neighborhood interference index is:Ix = 0.003 626 + 0.000741 418A (r2 = 0.97 P < 0.01)and result in the disappearance of Cunninghamia community. Based on the degree of variation of the tendency, it is recommended that selective cutting should be applied for economic cause.