土壤因子对次生森林群落演替的影响

EFFECTS OF SOIL FACTORS ON THE SECONDARY SUCCESSION OF FOREST COMMUNITY

采用聚类分析、主分量分析和回归分析对紫金山次生森林群落的系列群落，演替途径和演替速率进行了研究。紫金山次生森林群落目前的演替趋势为马尾松群落→马尾松、落叶阔叶树群落→落叶阔叶树、马尾松群落→落叶阔叶树群落，但在不同的土壤条件下，阔叶树的侵入、生长状况不同，群落具体的发展途径和速率有差异。制约森林演替的主要土壤因子为土壤水分和土壤厚度，它们通过对马尾松、枫香、黄檀、栓皮栎等主要树种显著度，对树种竞争能力的作用，对演替产生影响。随着土壤水分和土壤厚度增加，马尾松相对显著度的剧烈减少，黄檀相对显著度的缓慢增加以及枫香和栓皮栎相对显著度的迅速发展。

Cluster analyses, principal component analyses and regression analyses were used to study serial communities, successional pathways and successional velocities of the secondary forests in Zijin mountain. The current successional trend of the forest was: Pinusmassoniana community→ P. massoniana + deciduous broadleaved tree species community→deciduous broadleaved tree species + P. massoniana community→deciduous broadleaved tree species community. But different pathways and speed could be found on several soil conditions, because of the differences of invasion and growth of the deciduous broadleaved tree species on different soil factors. Soil depth and soil humidity, were the main factors to control succession through affecting the dominance and competitive capacity of the major tree species such as P. massoniana, Liquidambar formasana, Dalbergia hupeana and Quercus variabilis, The relative changes between increasing of soil depth, soil humidity and decreasing of dominace of P. massoniana, between increasing of soil depth, soil humidity and slowly increasing of dominance of D. hupeana, between increasing of soil depth, soil humidity and rapidly increasing of dominance of L. formasana and Q. variabilis happened in the secondary forests.