中国北方蒙古栎林起源和发展的初步探讨

古生态学的研究显示 ,栎林 (包括蒙古栎林 )在华北地区和东北地区的分布在地质历史时期不是一成不变的 ,其优势度也呈现上下波动 ,栎树优势度的增减是由于地质历史时期气候的变化造成的 ;蒙古栎的起源时间可能不早于上新世中期 ,蒙古栎林的起源也应不早于上新世中期。蒙古栎林的起源原因有 2种 ,即火与人类的反复砍伐。火是原生性质蒙古栎林在地质历史时期存在和扩散的根本原因 ,过度的人类活动 (主要是反复砍伐 )是促成现在蒙古栎次生林占优势地位的主要原因 ,这是由蒙古栎这个树种的生物学特性决定的 ,在没有外界因素的干扰和火减少的情况下 ,蒙古栎在演替过程中逐渐被耐荫的树种所取代 ,但是在中国北方 ,由于人类活动的加剧 ,蒙古栎林的优势度有增加的趋势。

Preliminary discussion on the origin of Quercus mongolica forest in north China

Paleoecological studies indicated that domination of oak trees( including Quercus mongolica forest ) in north China changed in geological age because of climatic change. The fire caused the incidence of Quercus mongolica forest. Fire and human activities increased the domination of oak forests because of their biological features of oak trees. Cutting repeatedly was the main reason for the domination of Quercus mongolica forest in recent 100 years in north and east China. During the succession of the oak forest, the oak tree would be substituted by shade-tolerant species such as maple trees. With the increase of human activity, the dominance of Quercus mongolica forest in northern China will increase.